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1

Santiso, Quiñones Gustavo. "Octahedral versus trigonal prismatic rearrangements in MoF6 and WF6 derivatives." [S.l.] : [s.n.], 2005. http://www.diss.fu-berlin.de/2005/11/index.html.

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2

Klein, Nicole. "Synthese und Charakterisierung neuer mesoporöser und flexibler metallorganischer Gerüstverbindungen und deren Anwendung als Gasspeichermaterialien." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-98526.

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Die Entwicklung und Synthese im Bereich neuartiger poröser Systeme, im speziellen Metallorganische Gerüstverbindungen (engl.: Metall-organic Frameworks; MOFs), wird weltweit in vielen Forschergruppen intensiv bearbeitet. Aufgrund der Möglichkeit, dass sich die Materialeigenschaften individuell designen lassen und letztendlich spezifische Eigenschaften für eine ausgewählte Anwendung bereitgestellt werden können, stellen MOFs für einen weiten Forscherkreis eine interessante Materialienklasse dar. Im Rahmen dieser Arbeit stand die Synthese von neuartigen MOFs im Vordergrund, welche geeignete Eigenschaften für eine effiziente Speicherung von Gasen im Nieder- als auch im Hochdruckbereich besitzen. Dabei wurde zum einen Augenmerk auf die Synthese mesoporöser MOF-Systeme gelegt. Hier lag die größte Herausforderung darin, die erhaltenen hochporösen Materialien in einer stabilen gastfreien Form zu erhalten. Ein weiterer Schwerpunkt war die Untersuchung von flexiblen MOF-Verbindungen und deren Eigenschaften in Abhängigkeit der Synthesebedingungen und der adsorbierten Spezies. Auf Basis der Copolymerisation verschiedener multifunktioneller Linkermoleküle konnten zwei mesoporöse Verbindungen und dazugehörige Isomorphe synthetisiert werden (DUT-6, DUT-23; DUT = Dresden University of Technology). Mit diesen Verbindungen konnte über die Kombination von unterschiedlich funktionellen Linkermolekülen eine erhöhte Netzwerkstabilität und damit einhergehend erhöhte Porosität erhalten werden. Sämtliche Verbindungen zeigen ausgezeichnetes adsorp-tives Verhalten und können aufgrund ihrer verschiedenen Eigenschaften in Bereichen der Hochdruckadsorption, Katalyse oder enantioselektiven Trennung Einsatz finden. Im zweiten Teil der Arbeit wurde das flexible Verhalten der „pillar-layer“ Verbindungen DUT-8(M) (M = Ni, Co, Zn, Cu) näher untersucht. Diese isomorphe Reihe zeichnet sich durch ihre hohe Netzwerkflexibilität in Abhängigkeit der integrierten Gastmoleküle sowie dem vorliegendem Metall-Dimer aus. DUT-8(M) zeigt unterschiedliche Adsorptionseigenschaften und unterschiedliches Stabilitäts- sowie Flexibilitätsverhalten.
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3

Flemming, Christine Juliette Jane. "Impact and nature of open metal sites: a water and carbon monoxide adsorption study on MOF-74 isostructural MOFs." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48992.

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In this work the magnesium, zinc, nickel and cobalt MOFs of the MOF-74 isostructural family are used to probe metal-dependent adsorbate interactions with water and with carbon monoxide because of their ability to generate open metal sites upon activation. An isostructural family is used so that the only variable from one MOF to another is the metal incorporated into the framework. For water adsorption isotherms with humidities up to 90%, the observed trend at 298K and 1 bar is Mg-MOF-74 > Zn-MOF-74 > Co-MOF-74 > Ni-MOF-74. This observed trend is due to Lewis acid-base interactions. When the weight effect is removed, differences are still observed, especially below 40% relative humidity, thereby confirming that there is a metal effect. These studies revealed that PXRD alone cannot indicate the level of structural decomposition and that none of the four isostructures fully retain their structural integrity on exposure to humidified air because of microstrain and/or the presence of oxygen; more studies examining the extent of structural decomposition need to be undertaken. For carbon monoxide adsorption the general observed trend for P < 4 bar and temperatures of 298, 313 and 333K is Co-MOF-74 > Ni-MOF-74 > Zn-MOF-74 > Mg-MOF-74. This trend is based on π-backbonding interactions. Here again, differences remain after removal of the weight effect, confirming the metal dependence. Notably, Co-MOF-74 has the highest CO loading at 298K and 1 bar reported so far. Both the Toth and Virial Isotherms were used to fit the CO adsorption data followed by the use of the Clausius-Clapeyron equation to find the isosteric heats of adsorption, qst. The results from the Toth isotherm are more reliable and showed that qst remains constant as loading increases for Mg-MOF-74, decreases for Zn-MOF-74 and increases with loading for Co-MOF-74 and Ni-MOF-74; Ni-MOF-74 had the highest heat of adsorption at all loadings. It appears that using the Clausius-Clapeyron equation to calculate qst is an inappropriate method for Ni-MOF-74 so other methods such as calorimetry are recommended. It is also recommended to model the data of all the MOFs with other isotherm models such as Sips equation and to investigate the possibility of chemisorption for the cobalt and nickel isostructures. Finally, Henry’s constant results reveal that Ni-MOF-74 has the highest affinity for CO at low coverages.
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4

Stangl, Johannes Maria [Verfasser], Klaus [Gutachter] Müller-Buschbaum, and Maik [Gutachter] Finze. "Quantitative Feuchtesensorik mit lumineszierenden Ln-MOFs und Polymer-MOF-Matrix-Membranen / Johannes Maria Stangl ; Gutachter: Klaus Müller-Buschbaum, Maik Finze." Würzburg : Universität Würzburg, 2018. http://d-nb.info/1173088083/34.

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5

Hopkins, Jesse Bennett. "Infrared Spectroscopy of H2 Trapped in Metal Organic Frameworks." Oberlin College Honors Theses / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1250478492.

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6

Klimakow, Maria. "Metallorganische Gerüstverbindungen (MOFs)." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/17097.

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In dieser Arbeit werden das Potential der mechanochemischen Synthesemethode zur Herstellung von metallorganischen Gerüstverbindungen (MOFs) vorgestellt und mögliche Anwendungsgebiete aufgezeigt. Im Forschungsfokus bezüglich schnellerer und effizienterer Darstellungsmethoden ist die Mechanochemie eine aussichtsreiche Alternative. Die Feststoff-Reaktion ist ohne die Verwendung von Lösungsmitteln durchführbar, zeichnet sich durch verkürzte Reaktionszeiten und quantitativen Eduktumsatz aus und gilt somit als Green Chemistry-Methode, die stetig wachsende Bedeutung erlangt. Die Ergebnisse dieser Arbeit belegen, dass über die mechanochemische Synthese metallorganische Verbindungen in allen Dimensionalitäten herstellbar sind. Die Reaktionsparameter sind auf die Herstellung isostruktureller und strukturanaloger Verbindungen übertragbar. Es wurden Synthesebedingungen identifiziert, die die Produktbildung beeinflussen, so dass ihre Kontrolle zur gezielten Herstellung verschiedener Verbindungen diente. Des Weiteren wurden Reaktionsparameter ermittelt, die einen Einfluss auf die Eigenschaften des Produkts ausüben. Im Hinblick auf eine größtmögliche spezifische Oberfläche wurde die Synthese optimiert und eine postsynthetische Aktivierungsprozedur entwickelt, die gemeinsam in einer verbesserten Gasadsorptionskapazität resultieren und auf andere Verbindungen übertragbar sind. Die Ergebnisse zur Gasspeicherung zeigen ein erstes Anwendungspotential für mechanochemisch synthetisierte MOFs auf, die als feine Pulver mit vergrößerter Oberfläche erhalten werden. Weiterhin wurde die Einlagerung von Solvensmolekülen in die Poren eines MOFs untersucht. Dabei zeigte sich, dass das MOF seine Gitterparameter an die jeweiligen Gastmoleküle anpasst. Das Potential zur Interkalation von Feststoffen wird anhand der Einlagerung pharmazeutischer Wirkstoffmoleküle belegt. Katalytische Untersuchungen zeigen eine gute Aktivität des mechanochemisch synthetisierten Rohprodukts.<br>In this work the potential of mechanochemical synthesis to produce metal-organic frameworks (MOFs) is presented and possible applications for the materials are shown. In the focus of research regarding faster and more efficient methods of synthesis, mechanochemistry is an promising alternative. This solid-state reaction can be carried out without the use of solvent, exhibits shortened reaction times and a quantitative turnover of reactands. Therefore it is a method of green chemistry, and its importance is constantly increasing. The results show that mechanochemical synthesis is capable of producing metal-organic compounds in all dimensionalities. The reaction conditions can be transferred to synthesize isostructural and structural analogous compounds. Parameters influencing the formation of products were identified, and their control led to a well-aimed design of various compounds. In addition, conditions influencing the properties of the product were determined. In terms of a specific surface area as large as possible, the synthesis was optimized and a postsynthetic activation was developed, together resulting in an improved capacity for gas adsorption and transferrable to other compounds. The results concerning gas storage present one possible application of mechanochemically synthesized MOFs, that are produced as fine powders with enlarged surfaces. Furthermore, intercalation of solvent molecules in the pores of a MOF was investigated. It shows that the MOF adjustes its lattice paramters to the guest molecules. The potential to intercalate solid-state compounds is demonstrated using pharmaceutical drug molecules. Catalytic investigations show a good activity of the mechanochemically synthesized raw product.
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7

Heinke, Lars. "Diffusion in MOFs." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198185.

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8

Weckmann, Armin. "Material migration in tokamaks: Studies of deposition processes and characterisation of dust particles." Licentiate thesis, KTH, Fusionsplasmafysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-178026.

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Thermonuclear fusion may become an attractive future power source. The most promising of all fusion machine concepts is the tokamak. Despite decades of active research, still huge tasks remain before a fusion power plant can go online. One of these important tasks deals with the interaction between the fusion plasma and the reactor wall. This work focuses on how eroded wall materials of different origin and mass are transported in a tokamak device. Element transport can be examined by injection of certain species of unique and predetermined origin, so called tracers. Tracer experiments were conducted at the TEXTOR tokamak before its final shutdown. This offered an unique opportunity for studies of the wall and other internal components: For the first time it was possible to completely dismantle such a machine and analyse every single part of reactor wall, obtaining a detailed pattern of material migration. Main focus of this work is on the high-Z metals tungsten and molybdenum, which were introduced by WF6 and MoF6 injection into the TEXTOR tokamak in several material migration experiments. It is shown that Mo and W migrate in a similar way around the tokamak and that Mo can be used as tracer for W transport. It is further shown how other materials - medium-Z (Ni), low-Z (N-15 and F), fuel species (D) - migrate and get deposited. Finally, the outcome of dust sampling studies is discussed. It is shown that dust appearance and composition depends on origin, formation conditions and that it can originate even from remote systems like the NBI system. Furthermore, metal splashes and droplets have been found, some of them clearly indicating boiling processes.<br><p>QC 20151203</p>
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9

Schloss, Jennifer M. "Infrared Spectroscopy of Trapped Gases in Metal-Organic Frameworks." Oberlin College Honors Theses / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1308537119.

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10

Espín, Martí Jordi. "The photothermal effect in MOFs." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/665204.

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Aquesta Tesi està dedicada a l’estudi de la interacció de la llum amb Polímers de Coordinació (CPs) i Xarxes Metalorgàniques (MOFs). S’ha seguit dos camins per aconseguir aquest objectiu; en primer lloc estudiant l’efecte fototèrmic observat en diferents subfamilies de MOFs, els quals, un cop irradiats amb llum UV‐Vis, presenten un escalfament local. Aquest augment de temperatura ha resultat útil tant en processos d’activació de MOFs com en Modificacions Covalents Post‐Sintètiques (CPSM). Per altra banda, sintetitzant nous CPs seguint l’estratègia de disseny de lligands fent servir complexos de coordinació de Ru2+‐terpiridines amb propietats de captació de llum. El Capítol 1 inclou una introducció general als CPs i MOFs, amb una visió històrica del seu descobriment i evolució, així com algunes de les múltiples aplicacions en les que aquests materials es poden implicar. En aquest sentit, ens hem centrat en les aplicacions que aprofiten la llum com a estímul extern. En el Capítol 2, hem resumit l’objectiu principal d’aquesta Tesi i n’hem detallat els objectius parcials. El Capítol 3 presenta una introducció als fonaments de la conversió de llum a calor en diferents materials. Alguns exemples de composites de MOFs, on les nanopartícules demostren un comportament fototèrmic, es troben resumits. Per altra banda també s’hi expliquen alguns dels mètodes més emprats per evacuar molècules que obstrueixen els porus de MOFs (activació). En aquest capítol es demostra que els MOFs també presenten efecte fototèrmic i que aquest efecte es pot utilitzar per a activar‐los eliminant les molècules de dissolvent un cop irradiats amb una làmpada UV‐Vis per temps curts. En el Capítol 4, la Modificació Post‐Sintètica (PSM) de MOFs es resumeix basant‐se en les interaccions entre l’esquelet del material porós i els agents modificants. També s’hi inclouen algunes estratègies alternatives per realitzar aquestes transformacions. En aquest sentit, l’ús de la calor local generada a partir de irradiar MOFs és utilitzada per aconseguir reaccions de CPSM. MOFs amb funcionalitzacions amino que presenten un fort efecte fototèrmic i anhídrids o aldehids es van mesclar (sense dissolvent) i la posterior exposició a llum UV‐Vis per temps curts va afavorir la fusió dels reactius i la reacció covalent. En el Capítol 5, les propietats d’absorció de llum i fototèrmiques d’alguns complexos organometàl∙lics s’exemplifiquen. També s’hi descriu l’estratègia beneficiosa de confinar aquests grups com a unitats estructurals en CPs i MOFs per a millorar la seva activitat. La síntesi i caracterització de tres nous CPs construïts a partir de complexos de Ru2+‐terpiridina i ions catalítics és descrita en aquest apartat. La caracterització fototèrmica d’aquests nous CPs demostra que presenten temperatures màximes en el rang dels MOFs amb un efecte fototèrmic més elevat. També es proposa realitzar un estudi dels CPs en reaccions de fotocatàlisi aprofitant la disposició dels complexes de Ru i dels ions metàl∙lics en els nodes.<br>This Thesis is devoted to the study of the interaction of light with Coordination Polymers (CPs) and Metal‐Organic Frameworks (MOFs). Two strategies have been followed to accomplish this objective. The first approach consisted on the study of the photothermal effect observed in different subfamilies of reported MOFs, which exhibited local heating upon UV‐Vis irradiation. Such temperature increase was proved useful for MOF activation and Covalent Post‐Synthetic Modification (CPSM) purposes. The second strategy was based on the synthesis of CPs following a ligand design approach using light‐harvesting Ru2+‐terpyridine complexes. Chapter 1 encloses a general introduction to CPs and MOFs, containing a historical overview of their discoveries and evolution, as well as some of the multiple applications in which these materials are involved. In this sense, we have focused on the applications arisen from the use of light as external stimulus. In Chapter 2, we have summarized the main objective of this Thesis and detailed the specific sub goals. Chapter 3 introduces the fundamentals of the light‐to‐heat conversion in different materials. Some examples of MOFs composites, where the nanoparticles exhibit the photothermal properties are reviewed. Moreover, a summary of some of the most common methods for removing guests from MOF pores (activation) is included. In this chapter, we demonstrate that MOFs also show photothermal effect and that this effect can be used to activate them by removing the solvent molecules after their irradiation with a UV‐Vis lamp for short periods. In Chapter 4, Post‐Synthetic Modification (PSM) of MOFs is reviewed based on the interactions between the framework and the desired modifying agents. To this end, some alternative strategies to perform such reactions are included. Thereafter, the use of the local heat generated upon MOF irradiation in CPSM reactions is reported. Amino‐tagged MOFs with strong photothermal effects and anhydrides or aldehydes were mixed (sovent‐free), and subsequent UV‐Vis exposure for short times allowed the melting of the reagents and the covalent reaction. In Chapter 5, the light‐harvesting and photothermal properties of some organometallic complexes are exemplified. The beneficial strategy of confining these moieties as building units in CPs and MOFs for enhancing their performance is described. The synthesis and characterization of three new CPs build up from Ru2+‐terpyridine complexes is reported here. Their photothermal characterization is performed and the new CPs showed maximum temperatures in the range of the MOFs with the strongest photothermal effect. In addition, future assessment of the CPs in photocatalytic reactions might be carried out, taking advantage of the close disposition of the Ru complexes and the metal ions of the nodes.
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11

SANTOS, Guilherme de Coimbra. "Estudo da decodificação de aromático via luminescência de MOF, e de novos compósitos, em fase sólida, à base de MOFs e curcubiturila, na adsorção seletiva de corantes." Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/25145.

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Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-07-19T22:53:08Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Guilherme de Coimbra Santos.pdf: 6601677 bytes, checksum: 98f83ae5c0517751b976e593f82b4003 (MD5)<br>Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-07-20T21:39:55Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Guilherme de Coimbra Santos.pdf: 6601677 bytes, checksum: 98f83ae5c0517751b976e593f82b4003 (MD5)<br>Made available in DSpace on 2018-07-20T21:39:55Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Guilherme de Coimbra Santos.pdf: 6601677 bytes, checksum: 98f83ae5c0517751b976e593f82b4003 (MD5) Previous issue date: 2017-02-15<br>CNPQ<br>Este trabalho apresenta a síntese da já conhecida MOF [Zn2(BDC)2(dpNDI)]n (BDC = 1,4-benzenodicarboxilato, dpNDI = N’N’-di(4-piridil)-1,4,5,8-naftalenodiimida), mas, agora dopada em diferentes percentagens (0,1%, 0,5%, 1%, 2% e 5%) com o íon európio (íon sonda), por via solvotermica. Após suas caracterizações, observam-se respostas espectroscópicas, frente à monoaromático, favoráveis na identificação de moléculas hóspedes. A síntese e caracterização de redes de coordenação cristalinas, bem como de compósitos a base de carvão ativado, a partir de íons lantanídeos (Pr³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Gd³⁺, Dy³⁺, Er³⁺, Tm³⁺ e o Yb³⁺) com emprego do ligante flexível, succinato, utilizando-se a técnica hidrotermal para obtenção desses sistemas, foram realizadas, além de investigações de sistemas mixmetal nessa mesma matriz carbonácea. Novos compósitos porosos LnBDC@CA (CA = Carvão ativado, Ln = Pr³⁺; Nd³⁺; Sm³⁺; Eu³⁺; Gd³⁺; Er³⁺; Tm³⁺ e Yb³⁺ e BDC = 1,4benzenodicaboxilato) e CB[6]@CA (CB[6] = Cucurbit[6]uril) foram obtidos utilizando via hidrotermal. O LnBDC e o CB[6] estão localizados dentro dos poros do carvão, como foi observado em análise MEV-EDS, Raio X de pó e IV. A análise de porosimetria mostrou valores tipicamente entre o material CA e LnBDC, com tamanho de poro e área de superfície, respectivamente, 29,56 Å e 353,98 m²g⁻¹ para LnBDC@CA e 35,53 Å e 353,98 m²g⁻¹ para CB[6]@CA. Ambos os materiais mostraram boa capacidade de adsorção para o alaranjado de metila (MO) e o azul de metileno (MB) com seletividade em função do pH. Em meio ácido, ambos os materiais apresentam seletividade por MB e em pH alcalino para o MO, com desempenho perceptível para o CB[6]@CA. Adicionalmente, a luminescência do európio foi utilizada como sonda estrutural para investigar o ambiente de coordenação do íon Eu³⁺ no compósito EuBDC@CA após experimentos de adsorção.<br>This work presents the synthesis Already known of MOF [Zn2(BDC)2(dpNDI)] (BDC = 1,4-benzenedicarboxylate, dpNDI = N'N'-di (4-pyridyl) -1,4,5,8 - naphthalenediimide), but now doped in different percentages (0.1%, 0.5%, 1%, 2% and 5%) with the europium ion (probe ion) by Solvothermal synthesis. After their characterizations, spectroscopic responses are observed, in touch to monoaromatic, favorable in the identification of guest molecules. The synthesis and characterization of crystalline coordination networks, as well as activated carbon based composites, from lanthanide ions (Pr³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Gd³⁺, Dy³⁺, Er³⁺, Tm³⁺ e o Yb³⁺) with the use of flexible ligands, succinate, using the hydrothermal technique to obtain these systems, were performed, in addition to investigations of mixmetal systems in this same carbonaceous matrix. New porous composites LnBDC@AC (AC= Activated carbon, Ln= Pr3+; Nd³⁺; Sm³⁺; Eu³⁺; Gd³⁺; Er³⁺; Tm³⁺ e Yb³⁺ and BDC= 1,4benzenedicaboxylate) and CB[6]@AC (CB[6]= Cucurbit[6]uril) were obtained using hydrothermal route. The LnBDC and CB[B] are located inside the pore of the carbon materials as was observed in SEM-EDS, XRPD and FT-IR analysis. Porosimetry analysis showed values typically between AC and LnBDC material, with pore size and surface area, respectively, 29,56 Å and 353.98 m2g-1 for LnBDC@AC and 35,53 Å and 353.98 m²g⁻¹ for CB[6]@AC. Both materials showed good absorptive capacity of metil orange (MO) and methylene blue (MB) with selectivity as a function of pH. In acid medium, both materials present selectivity by MB and alkaline pH for MO, with notable performance for CB[6]@AC. Additionally, europium luminescence was used as structural probe to investigate the coordination environment of Eu³⁺ ions in the EuBDC@AC composite after adsorption experiment.
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Hoffmann, Herbert C. "NMR-SPEKTROSKOPIE AN FLEXIBLEN UND CHIRALEN METAL-ORGANIC FRAMEWORKS (MOFs)." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-149597.

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Es wurden verschiedene NMR-spektrokopische Messungen an flexiblen und chiralen MOFs durchgeführt. Zur Untersuchung der Porensysteme kamen 129Xe-NMR und 13C-NMR an adsorbiertem CO2 zum Einsatz, während die MOF-Gitter und ihre Wechselwirkungen mit adsorbierten Gastmolekülen mittels 13C- und 1H-MAS-NMR-Spektroskopie studiert wurden. Während DUT-8(Ni) Flexibilität zeigt, weist DUT-8(Cu) ein starres Gitter auf. Die Flexibilität der sogenannten Solid-Solutions hängt in ausgeprägter Weise vom Verhältnis der funktionalisierten bdc-Linker 2,5-bme-bdc und db-bdc ab. Dieses Verhältnis hat zudem einen großen Einfluss auf die Orientierung der adsorbierten CO2-Moleküle. Es wurde erstmals eine Methode vorgestellt, die den Festkörper-NMR-spektroskopischen Nachweis chiraler Seitengruppen in chiralen MOFs erlaubt, wie anhand des chiral modifizierten UMCM-1 (ChirUMCM-1) demonstriert wurde. Die Chiralität kann einen NMR-spektroskopisch messbaren Einfluss auf die intrinsische Dynamik des MOF-Gitters ausüben, wie am chiral modifizierten DUT-32 deutlich wurde, dessen chirale Seitengruppe selektiv 15N- und 13C-isotopenmarkiert wurde.
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13

Chen, Yipei. "Synthesis of MOFs for carbon capture application." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/55542/.

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The work in this thesis focuses on the synthesis of metal organic frameworks (MOFs) both in batch and continuous work. Improvements are made in both, compared to the previous research. Furthermore, post-modification experiments are conducted to advance the characteristics of end product. Also, their application as solid sorbents in carbon capture is investigated. In Chapter 1, the background of greenhouse gas emissions is reviewed and discussed, followed by the development of carbon capture technologies and different adsorbents used in post-combustion carbon capture. An introduction to metal organic frameworks is then presented, including a literature review of the research to date, and various synthesis methods including batch and continuous routes. The last part of this chapter presents a literature review on how pre-synthetic design and post-synthetic modification synthesis of MOFs can be achieved. The theories and introductions of the characterization techniques used in this thesis are discussed in detail in Chapter 2. Chapter 3 discusses a new batch method for the efficient synthesis of micro-sized HKUST-1 with high yield (84%) under mild conditions. Different activation methods are conducted in the washing process. Both ethanol and methanol are tested to remove the impurities in pores of the samples. Finally, the optimal sample of HKUST-1 achieved is shown to produce a relatively high surface area (1615 m2/g) with a CO2 adsorption of 8.1% (measured by TGA at 1 atm and 27 oC). A step increase in the surface area is made by immersing the powders into a solution consisting of NaCl, water and methanol. Nano scale HKUST-1 is synthesized by adding trimethylamine (TEA) solution with the organic ligand precursor. The reaction rate is accelerated with this case because TEA solution is able to deprotonate the trimesic acid (the organic ligand). The method for nano scale HKUST-1 synthesis is the focus of Chapter 4. Chapter 5 reports the continuous synthesis process of HKUST-1 and ZIF-8. This work builds on previous work at Nottingham. A counter-current Nozzle reactor is used in this work. The products were compared with commercial equivalents. Post-synthetic modification of HKUST-1 was made to improve the hydrophobicity of HKUST-1 to extend its resilience to breakdown in the presence of moisture. In Chapter 6, a hybrid material TiO2@ZIF-8 is synthesized using the same reactor. Different reactor configurations were also used to generate a range of different products that are then compared. To conclude, a summary of the work conducted in this thesis is presented in Chapter 7, followed by a discussion on potential future work.
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14

Heinke, Lars. "Diffusion in MOFs: the surface barrier phenomenon." Diffusion fundamentals 24 (2015) 19, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14533.

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15

Morris, Samuel Alexander. "X-ray studies of zeolites and MOFs." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/9891.

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This thesis is largely a study of the ADOR process (assembly-disassembly-organisation-reassembly) when applied to zeolite UTL. The final chapter of this thesis deals with the adsorption of the medical gases NO and CO onto the metal organic framework NiNaSIP. Chapter 4 is devoted to the disassembly and organisation steps of the ADOR process. Calcined UTL was hydrolysed using 0.1 – 12 M HCl solutions from 75 – 95 °C run over 10 mins to 72 hrs. A three step mechanism is proposed, which is comprised of an initial rapid hydrolysis that removes the majority of the interlayer constituents of UTL, causing the silica-rich layers to largely collapse. This is followed by a slow, temperature and molarity dependent, deintercalation process that sees the remainder of the interlayer material removed resulting in the full collapse of the layers to form IPC-1P. The third step is a temperature and molarity dependent rebuilding process, whereby the interlayer region is slowly rebuilt, eventually forming a precursor which upon calcination becomes IPC-2 (OKO). Chapter 5 uses the pair distribution function (PDF) technique to structurally confirm the intermediate of the ADORable zeolite UTL. The intermediate, IPC-1P, is a disordered layered compound formed by the hydrolysis of UTL in 0.1 M HCl. Its structure is unsolvable by traditional X-ray diffraction techniques. The PDF technique was first benchmarked against high-quality synchrotron Rietveld refinements of IPC-2 (OKO) and IPC-4 (PCR) – two end products of IPC-1P condensation that share very similar structural features. An IPC-1P starting model derived from density functional theory was used for the PDF refinement, which yielded a final fit of Rw = 18% and a geometrically reasonable structure. This confirms that the layers do stay intact throughout the ADOR process, and shows that PDF is a viable technique for layered zeolite structure determination. Chapter 6 examines the reassembly stage by following the in-situ calcination of a variety of hydrolysed intermediates into their three-dimensional counterparts. Beamline I11 at Diamond Light Source provided high-quality PXRD patterns as a function of temperature, which were refined against using sequential Pawley refinements to track the unit cell changes. 0.1, 1.75, 2.5 and 12 M hydrolysed lamellar precursor phases were calcined. The largest unit cell changes were observed for 0.1 M, and the smallest for 12 M. This shows that increasing the molarity must prebuild most of the interlayer connections, such that upon calcination, only minimal condensation occurs to fully connect the layers. Chapter 7 probes the uptake of the medical gases CO and NO into the metal organic framework NiNaSIP. An in-situ single-crystal XRD study was undertaken using an environmental gas cell at beamline 11.3.1 at the Advanced Light Source. NiNaSIP was first dehydrated to reveal an open nickel site, which acted as the main site of adsorption for the inputted gases. NO was observed in a bent geometry at an occupancy of 40 % and a Ni – N bond length of 2.166(16) Å. The oxygen was modelled to be disordered over two sites. CO was not fully observed, as only the carbon was able to be modelled with an occupancy of 31.2 % and a Ni – C bond length of 2.27(3) Å.
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16

Barreteau, Daniel. "Description du mofu-gudur : langue de la famille tchadique parlée au Cameroun /." Bondy : ORSTOM, 1988. http://catalogue.bnf.fr/ark:/12148/cb349547561.

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17

Hausdorf, Steffen. "Bildungsbedingungen und rationale Synthesestrategien." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-77613.

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MOF-5 ist der Archetyp einer neuartigen Klasse hochporöser Materialien, den Metal Organic Frameworks, die unter anderem zur Anwendung als effektive Gasspeicher geeignet sind. Im Rahmen dieser Arbeit werden die seiner Bildung zugrunde liegenden Reaktionen untersucht. Aus den Erkenntnissen dieser Untersuchungen wurden zwei neue Syntheseverfahren entwickelt. Eines der Verfahren beruht auf der Phasenumwandlung von Zinkterephthalaten und ermöglichte die Laborsynthese von MOF-5 in 100 g-Mengen. Ein zweites Verfahren bedient sich des Strukturaufbaus mit Hilfe vorgefertigter anorganischer Cluster, wodurch erstmals die Synthese von MOF-5-Homologen anderer Metalle als Zink gelang.
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18

Çamur, Ceren. "Advances on the synthesis of MOFs at scale." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667179.

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La presente tesis doctoral ha sido dedicada al desarrollo y optimización de metodologías para la síntesis de MOFs en medio acuoso, así como su conformación y el avance hacia la producción a gran escala de estos materiales. El primer capítulo presenta una breve introducción a los materiales porosos, empezando por los ejemplos presentes en la naturaleza, a los que luego sigue una breve historia sobre los MOFs y sus principales aplicaciones. Se prestará también especial atención a las metodologías usadas actualmente en la síntesis a gran escala de MOFs y su posterior procesado. El segundo capítulo presenta los objetivos, generales y específicos, de esta tesis. En el tercer capítulo se ilustra el uso de complejos metálicos de acetilacetonato como precursores alternativos en la síntesis acuosa a baja temperatura de varios MOFs, entre ellos MOFs basados en Zr, Fe y Al. Para cada material (UiO-66-NH2, Zr-fumarato, UiO-66-(OH)2, UiO-66-(COOH)2, MIL-88A y CAU-10), se definieron y optimizaron diversos parámetros experimentales con el fin de aumentar el rendimiento y la calidad del material final. Finalmente, se confirma la escalabilidad de esta metodología a través de una síntesis optimizada a gran escala de UiO-66-NH2 en agua a temperatura ambiente. El cuarto capítulo demuestra el uso de la técnica de secado por atomización, o ‘Spray Drying’, como un método “verde” y escalable para la producción de Zr-MOFs en forma de cuentas esféricas. Se definirá la importancia de diversos factores experimentales, y se demostrará su impacto en la síntesis de UiO-66-NH2 y Zr-fumarato. Finalmente, la escalabilidad del método será probada a través de una síntesis acuosa optimizada de UiO-66-NH2 a escala de gramos. Finalmente, el capítulo final se estudia el proceso de estructuración de varios MOF obtenidos con la técnica de ‘Spray Drying’ (HKUST-1 y UiO-66- NH2) y de lotes de síntesis (UiO-66 y UiO-67) y su influencia en sus propiedades de adsorción. Tras ser modelados en forma de pastilla a diferentes presiones, se estudiaron sus nuevas propiedades mecánicas y de superficie.<br>The present PhD Thesis has been dedicated to the development of basic knowledge on aqueous synthesis methodologies of MOFs and their shaping in order to make advances towards the large scale production of MOFs. The first chapter presents a brief introduction to the porous materials, starting with the examples from nature, which is then followed by a short history of MOFs and their main applications. Additionally, we pay special attention to the current methodologies that are performed for the synthesis of MOFs at scale and downstream processes. The second chapter consists of general and specific objectives of this Thesis. In the third chapter, the usage of metal acetylacetonate complexes as an alternative metal salt for the synthesis of MOFs is illustrated in water for several MOFs, including Zr-, Fe- and Al- based MOFs at low temperatures. For each MOF (UiO-66-NH2, Zr-fumarate, UiO-66-(OH)2, UiO-66-(COOH)2, UiO-66- COOH, MIL-88A and CAU-10), critical experimental parameters are defined and optimized to obtain high quality materials with high yields. Finally, the scalability of the methodology is shown with the gram scale synthesis of UiO- 66-NH2 by using optimized parameters in water at room temperature. The forth chapter demonstrates the continuous flow spray-drying technique that can be used as a green and scalable method to produce Zr-MOFs in the form of spherical beads. The influences of the important experimental factors are defined and the impact of those parameters on the synthesis of UiO- 66-NH2 and Zr-fumarate is shown. Finally, the scalability of the methodology is proven with the gram scale synthesis of UiO-66-NH2 by using optimized parameters in water. In the final chapter, the shaping process of the several MOFs that were synthesized by the spray-drying (HKUST-1 and UiO-66-NH2) and batch (UiO- 66 and UiO-67) synthesis methodologies is demonstrated. Mild pelletization technique is used to shape the MOFs into tablets to study textural and mechanical properties.
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19

Christie, Patricia Dianne 1967. "Preparation of isotopically labeled MoFe protein of nitrogenase." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11229.

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20

Senkovska, Irena, and Stefan Kaskel. "Ultrahigh porosity in mesoporous MOFs: promises and limitations." Royal Society of Chemistry, 2014. https://tud.qucosa.de/id/qucosa%3A35957.

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Mesoporous MOFs are currently record holders in terms of the specific surface area with values exceeding 7000 m2 gˉ¹, a textural feature unattained by traditional porous solids such as zeolites, carbons and even by graphene. They are promising candidates for high pressure gas storage and also for conversion or separation of larger molecules, whose size exceeds the pore size of zeolites. The rational strategies for synthesis of mesoporous MOF are outlined and the unambiguous consistent assessment of the surface area of such ultrahighly porous materials, as well as present challenges in the exciting research field, of mesoporous MOFs are discussed. The crystallinity, dynamic properties, functional groups, and wide range tunability render these materials as exceptional solids, but for the implementation in functional devices and even in industrial processes several aspects and effective characteristics (such as volumetric storage capacities, recyclability, mechanical and chemical stability, activation) should be addressed.
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21

Andrade, Gabriela Carolina Guimarães. "Reação de genótipos de soja ao mofo branco." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/7092.

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Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-04-06T15:50:48Z No. of bitstreams: 2 Tese - Gabriela Carolina Guimarães Andrade - 2015.pdf: 990973 bytes, checksum: d70848427ff4141f0bdaabe56c327b38 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)<br>Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-04-06T15:51:05Z (GMT) No. of bitstreams: 2 Tese - Gabriela Carolina Guimarães Andrade - 2015.pdf: 990973 bytes, checksum: d70848427ff4141f0bdaabe56c327b38 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)<br>Made available in DSpace on 2017-04-06T15:51:05Z (GMT). No. of bitstreams: 2 Tese - Gabriela Carolina Guimarães Andrade - 2015.pdf: 990973 bytes, checksum: d70848427ff4141f0bdaabe56c327b38 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-06-19<br>White Mold, caused by Sclerotinia sclerotiorum fungi, is, currently, one of the most important diseases of soybean, causing considerable economic losses and is of difficult control. The Fungi has more than 400 host species, including crops of agronomical importance as soybean, common beans and sunflower. The dissemination is mainly accomplished by infected seeds or by the presence of sclerotium. Genetic resistance is the most effective of plant disease control but is not well known about the soybean varieties resistance in Brazil and the current inoculation methods do not always have good correlation with field data. The main goals of this study were the evaluation of the resistance of soybean genotypes in two environments, Barreira – BA and Jatai – GO, correlate the rainfall with the variables analyzed, test two different methods, one in the greenhouse using tooth pick and other in the laboratory using oxalic acid, as well as correlate the data from the experiments in the fields with the greenhouse and the sensibility to the oxalic acid. According to the data analyzed, there are differences between genotypes of soybean in respect to the resistance of white mold. Early genotypes and more resistant to lodging were more resistant to white mold, but showing variations in the results. There was interaction between environment and soybean genotypes. The environment influenced meaningfully the occurrence of the disease in the tested genotypes, where in the severity correlate negatively and meaningfully with yield, in other words, the bigger the severity, the less the yield. The genotypes ANTA82, 2011L003 and 2011L005 had higher yields and were genetically more resistant to the disease. In respect to the methods used for the selection of resistant genotypes to white mold, it was seen that the oxalic acid method is an alternative for selection of resistant genotypes, since the variability of the pathogen is not considered, using the physiological traits of the genotypes. The experiments in the greenhouse are not correlated to the experiments in the field, due to the difficulty of reproducing equal symptoms that normally occur in the field. However, the method of the oxalic acid was shown to be reliable to be used in the phenotype of soybean cultivars but methodology adjusts should be done in future tests.<br>O mofo branco causado pelo fungo Sclerotinia sclerotiorum é, atualmente, uma das principais doenças da cultura da soja, causa prejuízos econômicos significativos e apresenta difícil controle. O fungo possui mais de 400 espécies hospedeiras, dentre elas importantes culturas agronômicas como a soja, o feijão e o girassol. A disseminação se dá principalmente pelas sementes infectadas ou pela presença de escleródios nas sementes. A resistência genética é a forma mais eficaz de controle de doenças de plantas, mas no Brasil pouco se conhece sobre a resistência genética de cultivares de soja ao mofo branco e os métodos atuais de inoculação nem sempre apresentam correlação positiva com os dados de campo. Assim, os objetivos do presente estudo foram avaliar a resistência de genótipos de soja em dois locais, Barreiras – BA e Jataí - GO, correlacionar a precipitação com as variáveis analisadas, testar dois métodos de avaliação, um em casa de vegetação pelo método do palito e outro em laboratório usando o ácido oxálico, correlacionar os experimentos a campo com os do teste do palito em casa de vegetação e a sensibilidade ao ácido oxálico. De acordo com os dados obtidos, existe diferença entre genótipos de soja com relação à resistência ao mofo branco. Materiais mais precoces e resistentes ao acamamento foram mais resistentes, mas com variações. Houve interação significativa entre local e genótipos de soja. O local afetou, significativamente, a ocorrência da doença nos genótipos testados, sendo que a incidência correlacionou negativamente com a produtividade, ou seja, quanto maior incidência, menor a produtividade. Os genótipos ANTA82, 2011L003 e 2011L005 se mostraram mais produtivos e com maior resistência genética. Quanto aos métodos utilizados para seleção de genótipos resistentes ao mofo branco, constatou-se que o método do ácido oxálico constitui uma alternativa para seleção de genótipos resistentes, já que a variabilidade genética do patógeno não é considerada, utilizando-se as características fisiológicas dos genótipos e mostrou correlação positiva com os resultados obtidos em campo. Os experimentos de casa de vegetação não correlacionaram com os experimentos de campo devido à dificuldade de reproduzir os mesmos sintomas que ocorrem no campo. Contudo o método do ácido oxálico se mostrou como uma alternativa viável para utilização na fenotipagem de genótipos de soja, mas alguns ajustes na metodologia precisam ser realizados em testes futuros.
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22

Ren, Chenhao. "Investigating Catalytic Selectivity of Nanoparticles encapsulated in MOFs:." Thesis, Boston College, 2021. http://hdl.handle.net/2345/bc-ir:109074.

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Thesis advisor: Chia-kuang Tsung<br>Thesis advisor: Dunwei Wang<br>Coating porous materials is a potential pathway to improve Catalytic performance of heterogeneous catalysts. The unique properties of Metal organic frameworks (MOFs) like huge surface area, long range order and high tenability make them promising coating materials. However, two traditional MOF encapsulation methods have their own issues. Herein, we synthesized Pt/Pd metal nanoparticles @UiO-66-NH2 via a one-pot in situ method which has good control of nanoparticles size while avoids the introduction of capping agent. The catalytic performance of synthesized Pt@UiO-66-NH2 is tested via selective hydrogenation of Crotonaldehyde. And the selectivity of our desired product achieves 70.42% which is much higher than merchant Pt catalysts. A step further, we used linker exchange to replace the original NH2-BDC linker of which amine group plays an important role in the coating process. After linker exchanging, the significant decreasing in selectivity of our target product demonstrates that the interaction between Pt and amine group does have some positive impacts on their catalytic performance. We hope our research could provide some insights of the MOFs and nanoparticles interface and help rational design of catalysts with high performance<br>Thesis (MS) — Boston College, 2021<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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23

Foucher, Damien. "Impact de l'eau dans la flexibilité des MOFs." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV059/document.

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Les MOFs sont des matériaux hybrides (organiques/inorganiques), nanoporeux et cristallin. La périodicité et la porosité apportent à ces matériaux des propriétés modulables par la topologie des réseaux et par les interactions entre le réseau et les molécules qui peuvent pénétrer dans les nanopores. L'adsorption de molécules dans les pores permet les séparations de mélanges, la séquestration sélective de molécules, la catalyse, le stockage de l'énergie etc... La flexibilité de certains MOFs est caractérisée par des variations de volume, parfois extrêmes, pouvant modifier de manières significatives les propriétés de ces matériaux. L'eau est tout à la fois une impureté inévitable dans les usages pratiques de ces composés mais également un composant important dans la modulation de la flexibilité. Bien que les nombreuses études publiées offrent une vision globale de la flexibilité et des interactions mises en jeu lors de l'adsorption de molécules de différentes natures, l'eau reste cependant une de celles qui résistent le plus aux mesures et aux interprétations. Cette thèse a eu pour objet d'utiliser de façon conjointe la diffraction des rayons-X synchrotron, des neutrons et a résonance magnétique nucléaire (RMN), pour ré-investiguer le rôle de l'eau dans la flexibilité de deux MOFs archétypiques, le UiO-66 (ZrCDC) et le MIL-53(Al). Nos résultats ont permis d'éclairer plusieurs points critiques. Avec ZrCDC il a pu être montré qu'en présence d'eau, les deux briques de constructions, inorganique et organique, sont couplées tout en ayant chacune une flexibilité distincte. Pour MIL-53(Al), la réinvestigation a été notablement plus conséquente, reprenant le suivi de la flexibilité en température de la phase anhydre et sous l'influence des gaz composants de l'air, oxygène et azote, puis l’étude du rôle de l'eau par RMN qui permet de caractériser les modifications structurales et dynamiques des phases anhydre et hydratée. Le suivi progressif de l'adsorption et de la désorption a notamment permis de mettre en évidence des phénomènes d'échange protoniques lents responsables des hystérèses observés. Ces résultats permettent de remettre en perspective les études antécédentes et de proposer une description renouvelée de la flexibilité de ces composés, comme une "horlogerie cristalline" des mouvements moléculaires<br>MOFs (metal-organic-frameworks) are hybrid (organic/inorganic) crystalline nanoporous materials. Periodicity and porosity provide to these materials modularity of properties by the topology of networks, and interactions between the framework and penetrating molecules in nanopores. Adsorption of molecules in pores allows for mixtures separation, selective sequestration of molecules, catalysis, storage of energy etc... Flexibility of some MOFs is characterized by extremes volume variations modifying properties of these materials. Water is at the same time an inevitable impurity in practical uses of such compounds and an equally significant component for modulation of flexibility. Although many published studies provide comprehensive views of the flexibility and interactions involved in the adsorption of molecules of different types, however water is one of those most resistant to measurements and interpretations. This thesis has been using jointly X-rays synchrotron and neutrons diffractions as well as nuclear magnetic resonance, to re-investigate water role on two archetypical MOFs, UiO-66 (ZrCDC) and MIL-53(Al). Our results obtained along this thesis shed some light on several critical points. With ZrCDC it has been demonstrated that both building blocks, inorganic and organic, exhibit each of them, in the presence of water a distinct flexibility, coupled together. For MIL-53(Al), this reinvestigation was noticeably more studied, covering flexibility in temperature of the anhydrous phase and under the influence of the components of air, oxygen and nitrogen. Then the study of water role in the anhydrous and hydrated phase by NMR characterized structural and dynamic changes. A progressive monitoring of adsorption and desorption, brought out slow proton exchange phenomena responsible of the hysteresis. These results allow for redefined a perspective of previous investigations and to propose a renewed description of flexibility of these materials, as a "crystalline clockwork" of molecular motions
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24

Bon, Volodymyr, Negar Kavoosi, Irena Senkovska, et al. "Tuning the flexibility in MOFs by SBU functionalization." Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A30176.

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A new approach for the fine tuning of flexibility in MOFs, involving functionalization of the secondary building unit, is presented. The 'gate pressure' MOF [Zn3(bpydc)2(HCOO)2] was used as a model material and SBU functionalization was performed by using monocarboxylic acids such as acetic, benzoic or cinnamic acids instead of formic acid in the synthesis. The resulting materials are isomorphous to [Zn3(bpydc)2(HCOO)2] in the 'as made' form, but show different structural dynamics during the guest removal. The activated materials have entirely different properties in the nitrogen physisorption experiments clearly showing the tunability of the gate pressure, at which the structural transformation occurs, by using monocarboxylic acids with varying backbone structure in the synthesis. Thus, increasing the number of carbon atoms in the backbone leads to the decreasing gate pressure required to initiate the structural transition. Moreover, in situ adsorption/PXRD data suggest differences in the mechanism of the structural transformations: from 'gate opening' in the case of formic acid to 'breathing' if benzoic acid is used.
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25

Bon, Volodymyr, Negar Kavoosi, Irena Senkovska, et al. "Tuning the flexibility in MOFs by SBU functionalization." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-219355.

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A new approach for the fine tuning of flexibility in MOFs, involving functionalization of the secondary building unit, is presented. The "gate pressure" MOF [Zn3(bpydc)2(HCOO)2] was used as a model material and SBU functionalization was performed by using monocarboxylic acids such as acetic, benzoic or cinnamic acids instead of formic acid in the synthesis. The resulting materials are isomorphous to [Zn3(bpydc)2(HCOO)2] in the "as made" form, but show different structural dynamics during the guest removal. The activated materials have entirely different properties in the nitrogen physisorption experiments clearly showing the tunability of the gate pressure, at which the structural transformation occurs, by using monocarboxylic acids with varying backbone structure in the synthesis. Thus, increasing the number of carbon atoms in the backbone leads to the decreasing gate pressure required to initiate the structural transition. Moreover, in situ adsorption/PXRD data suggest differences in the mechanism of the structural transformations: from "gate opening" in the case of formic acid to "breathing" if benzoic acid is used.
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26

Graham, Alexander John. "Effect of pressure on metal-organic frameworks (MOFs)." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8900.

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A growing field of research has evolved around the design and synthesis of a variety of porous metal-organic framework (MOF) materials. Some of the most promising areas for which these materials are potentially useful candidates include gas-separation, heterogeneous catalysis, and gas-storage, and all of these applications involve placing the MOF under pressure. There is clearly a need to understand the structural response of MOFs to applied pressure. Nevertheless, hitherto there are very few published investigations dedicated to determining the behaviour of porous hybrid materials under pressure. Through the use of high-pressure single-crystal X-ray diffraction studies, a series of MOF materials have been studied. Here we present the effect of pressure on a series of MOFs. In chapter 2, the effect of pressure on the prototypical MOF called MOF-5 was studied experimentally from ambient pressure to 3.2 GPa. Here, application of pressure was driven by the hydrostatic medium being forced into the pores of the MOF, which altered the mechanical properties of MOF-5, in particular, medium inclusion delayed the onset of amorphization. Complementary computational analysis was also performed to elucidate further the effect of medium inclusion on compressive behaviour. Detailed structural data was also collected as a function of pressure on the MOF Cu-btc. Application of pressure caused solvent to be squeezed into the pores (like MOF-5) until a phase transition occurred, driven by the sudden compression and expansion of equatorial and axial Cu–O bonds. High-pressure post-synthetic modification of a MOF is reported for the first time. On application of pressure of 0.2 GPa to the Cu-based MOF called STAM-1, a ligand exchange reaction takes place resulting in a change in pore size, shape, and hydrophilicity of the resulting pores. Here, we also demonstrate the ability to force hydrophilic molecules into hydrophobic pores using pressure, counteracting the hydrophobic effect. A high-pressure combined experimental and computational study has been carried to probe the effect of pressure on ‘breathing’ mechanisms in a zeolitic imidazolate framework (or ZIF) called ZIF-8. The penetration of guest molecules and the accommodation of pressure are shown to be inextricably linked to the rotation of methylimidazolate groups in the structure. Finally, the application of pressure to the MOF Sc₂BDC₃ and the nitro functionalized derivative Sc₂(NO₂-BDC)₃ was also studied. Here, the effect of chemical modification of the organic ligand, whilst maintaining framework topology, has been investigated as it pertains to compressibility. Directionality of compression is observed and this is rationalized with respect to the framework topology and medium inclusion/exclusion.
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27

Silva, Patrícia Vanessa Palma da. "Síntese e caracterização de MOFs – Metal Organic Frameworks." Master's thesis, Faculdade de Ciências e Tecnologia, 2012. http://hdl.handle.net/10362/8544.

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28

Ferreira, Denzil Sócrates Teixeira. "Meta, tracer - MOF with traceability." Master's thesis, Universidade da Madeira, 2009. http://hdl.handle.net/10400.13/80.

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The following document proposes a traceability solution for model-driven development. There as been already previous work done in this area, but so far there has not been yet any standardized way for exchanging traceability information, thus the goal of this project developed and documented here is not to automatize the traceability process but to provide an approach to achieve traceability that follows OMG standards, making traceability information exchangeable between tools that follow the same standards. As such, we propose a traceability meta-model as an extension of MetaObject Facility (MOF)1. Using MetaSketch2 modeling language workbench, we present a modeling language for traceability information. This traceability information then can be used for tool cooperation. Using Meta.Tracer (our tool developed for this thesis), we enable the users to establish traceability relationships between different traceability elements and offer a visualization for the traceability information. We then demonstrate the benefits of using a traceability tool on a software development life cycle using a case study. We finalize by commenting on the work developed.<br>Orientador: Leonel Nóbrega
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Gunatilleke, Wilarachchige D. C. B. "Analysis and New Applications of Metal Organic Frameworks (MOF): Thermal Conductivity of a Perovskite-type MOF and Incorporation of a Lewis Pair into a MOF." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7514.

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Metal organic frameworks have gained much attention due to their tunable pore sizes and very high surface areas. With the discovery many of these type materials the need has raised to look into new applications of theses porous frameworks. This thesis focuses on the synthesis of a new perovskite-type metal organic framework and measurement of its thermal conductivity in search of its applicability as a thermoelectric material. The second part of this work focuses on the synthesis of a metal organic framework incorporated with a Lewis pair for the first time. The optimum loading amount of the Lewis pair into the framework was also investigated.
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30

Barrio, Jorge Perez. "Synthesis and applications of novel metal-organic frameworks (MOFs)." Thesis, University of Liverpool, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526801.

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Belarbi, Hichem. "Élaboration des zéolithes nano-structurées M-ZSM-5 (M=Cu, Cr et Fe) : Etude comparée des solides poreux minéraux et organométalliques MOFs dans l’oxydation de méthylènes benzyliques." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20192.

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L'énergie, le développement durable et la santé sont au cœur des préoccupations actuelles de la planète. La disparition inéluctable des énergies fossiles, les conséquences graves des émissions de gaz carbonique sur l'environnement et la santé appellent des solutions rapides et efficaces pour suppléer aux premières et minimiser les autres.Parmi les solutions envisagées la catalyse hétérogènes représentés par les matériaux poreux, ces derniers ont prouvé leur efficacité, néanmoins des obstacles sont à corriger ou à contourner tel que le problème d'inaccessibilité des molécules encombrantes dans sites des micropores de ce matériau. Dans cette thèse nous avons essayé de trouver la solution à ce problème en travaillant sur des nanostructures ZSM-5.Dans une première étape, nous avons optimisé ce matériau en l'occurrence ZSM-5, avec une réduction de la taille des particules, d'une échelle microscopique vers une autre nanométrique, ce qui nous a permis d'augmenter la surface externe après une modification de certains paramètres. Dans la deuxième étape, et afin de donner une entité catalytique à notre support (la zéolithe), nous avons activé ce matériau par l'incorporation des cations, choisis en fonction d'une réaction bien spécifique, qui est celle d'oxydation des méthylènes benzéniques. Pour ce fait nous avons élaboré différents catalyseurs pour nos réactions.Nous avons conclu cette thèse par la catalyse avec la M-ZSM-5 (M = Cu, Cr et Fe) et une étude comparative est faite avec les MOFs qui portent les mêmes cations actifs dans leur partie minérale<br>Energy, sustainable development, and health are at the heart of contemporary concerns of the planet. The inevitable disappearance of fossil fuels, the severe consequences of carbon emissions on the environment and health require quick and effective solutions to supplement the first and minimize others. Among the solutions proposed, there are porous materials which have proven their effectiveness; however, there are still obstacles to be corrected or circumvented. In this thesis, we focus on the problem of bulky molecules' inaccessibility in micro pores of the materials we wish to study. In the first part, we optimize the material in this case, ZSM-5, with a reduction in particle size to a microscopic scale to another nano, which allows us to increase the external surface after changing certain parameters. In the second step, in order to give a catalytic entity to our support (zeolite), we activate with this material incorporating cations selected according to a specific property of the benzyl methylenes oxidation reaction. For this reason we developed different method of preparation. We conclude this thesis by catalysis with M-ZSM-5 (M = Cu, Cr and Fe) and a comparative study on the method of preparation and the MOFs that bears the same cations as mineral part which constitutes the materials
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32

Provost, Bianca. "An Improved N2 Model for Predicting Gas Adsorption in MOFs and using Molecular Simulation to aid in the Interpretation of SSNMR Spectra of MOFs." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/31930.

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Microporous metal organic frameworks (MOFs) are a novel class of materials formed through self-assembly of inorganic and organic structural building units (SBUs). They show great promise for many applications thanks to record-breaking internal surface areas, high porosity as well as a wide variety of possible chemical compositions. Molecular simulation has been instrumental in the study of MOFs to date, and this thesis work aims to validate and expand upon these efforts through two distinct computational MOF investigations. Current separation technologies used for CO2/N2 mixtures, found in the greenhouse gas-emitting flue gas generated by coal-burning power plants, could greatly benefit from the improved cost-effective separation MOF technology offers. MOFs have shown great potential for CO2 capture due to their low heat capacities and high, selective uptake of CO2. To ensure that simulation techniques effectively predict quantitative MOF gas uptakes and selectivities, it is important that the simulation parameters used, such as force fields, are adequate. We show that in all cases explored, the force field in current widespread use for N2 adsorption over-predicts uptake by at least 50% of the experimental uptake in MOFs. We propose a new N2 model, NIMF (Nitrogen in MoFs), that has been parameterized using experimental N2 uptake data in a diverse range of MOFs found in literature. The NIMF force field yields high accuracy N2 uptakes and will allow for accurate simulated uptakes and selectivities in existing and hypothetical MOF materials and will facilitate accurate identification of promising materials for CO2 capture and storage as well as air separation for oxy-fuel combustion. We also present the results of grand canonical and canonical Monte Carlo (GCMC and canonical MC), DFT and molecular dynamics (MD) simulations as well as charge density analyses, on both CO2 and N,N-dimethylformamide adsorbed in Ba2TMA(NO3) and MIL-68(In), two MOFs with non-equivalent inorganic structural building units. We demonstrate the excellent agreement found between our simulation results and the solid-state NMR (SSNMR) experiments carried out by Professor Yining Huang (Western University) on these two MOFs. Molecular simulation enables discoveries which complement SSNMR such as the number, distribution and dynamics of guest binding sites within a MOF. We show that the combination of SSNMR and molecular simulation forms a powerful analytical procedure for characterizing MOFs, and this novel set of microscopic characterization techniques allows for the optimization of new and existing MOFs.
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Schoenecker, Paul M. "High-throughput synthesis and application development of water-stable MOFs." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45919.

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Metal-organic frameworks (MOFs) are porous networks of metal-centers connect by organic ligands, which have potential for an array of applications including gas separations and storage, drug delivery, and molecular sensing. A multitude of structures are reported with specific pore geometries and functionalities, but MOFs are not currently implemented in consumer or industrial applications. Two major setbacks have hindered their transition to the applied level. 1) Many MOFs are not stable in the presence of ambient moisture. 2) Most syntheses are costly and take place under batch-style solvothermal conditions. This thesis addresses both of these setbacks and examines the performance potential of water-stable MOFs for selective gas adsorption. A representative set of MOFs are exposed to water, and structural effects are monitored from a before and after comparison to identify properties of water-stable MOFs. A novel continuous-flow MOF synthesis process is reported along with preliminary optimization experiments, which yield direct suggestions for future process improvements. Batch-style scale-up experiments are also conducted for three other MOFs, which provide insight into synthesis phenomena. Application specific results are reported for toxic chemical filtration and carbon dioxide removal from flue gas using MOFs. The thesis concludes by summarizing the experimental findings, discussing the application potential of specific MOFs, and recommending topics for future research projects. Pitfalls observed during this research are also directly discussed along with potential solutions.
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Gustafsson, Mikaela. "Metal-Organic Frameworks (MOFs) for Heterogeneous Catalysis : Synthesis and Characterization." Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-74431.

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Metal-organic frameworks (MOFs) are crystalline hybrid materials with interesting chemical and physical properties. This thesis is focused on the synthesis and characterization of different MOFs and their use in heterogeneous catalysis. Zeolitic imidazolate frameworks (ZIFs), including ZIF-4, ZIF -7 and ZIF -62, Ln(btc)(H2O) (Ln: Nd, Sm, Eu, Gd, Tb, Ho, Er and Yb), Ln2(bpydc)3(H2O)3, (Ln: Sm, Gd, Nd, Eu, Tb, Ho and Er), MOF-253-Ru and Zn(Co-salophen) MOFs were synthesized. Various characterization techniques were applied to study the properties of these MOFs. X-ray powder diffraction (XRPD), single crystal X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) were extensively used. The effect of synthesis parameters, such as batch composition and temperature, on the formation and morphology of ZIF-7 and ZIF-62 was studied. Structural transformation and flexibility of two series of lanthanide-based MOFs, Ln(btc)(H2O) (Ln: Nd, Ho and Er) and Ln2(bpydc)3(H2O)3, (Ln: Sm and Gd) upon drying and heating were characterized. Relations between metal coordination, structure flexibility and thermal stability among the Sm2(bpydc)3(H2O)3, Nd(btc)(H2O) and MOF-253 were investigated. Salophen- and phenanthroline-based organic linkers were designed, synthesized and characterized. Metal complexes were coordinated to these linkers to be used as catalytic sites within the MOFs. Catalytic studies using two MOF materials, Ln(btc) and MOF-253-Ru, as heterogeneous catalysts in organic transformation reactions were performed. The heterogeneous nature and recyclability of these MOFs were investigated and described.<br><p>At the time of doctoral defence the following papers were unpublished and had a status as follows: Paper nr 4: Submitted; Paper nr 5: Submitted</p>
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Krautwurst, John [Verfasser]. "Koordinationspolymere und MOFs auf Basis fluorierter tritopischer Carboxylatlinker / John Krautwurst." München : Verlag Dr. Hut, 2017. http://d-nb.info/1147674450/34.

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36

Iqbal, J. "Oxidizing abilities of UF6̲, MoF6̲, WF6̲ and NO'+ in acetonitrile." Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375436.

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37

Wutzki, Carlos Rafael. "CONTROLE ALTERNATIVO, BIOLÓGICO E QUÍMICO DO MOFO BRANCO NA SOJA." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2014. http://tede2.uepg.br/jspui/handle/prefix/2253.

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Made available in DSpace on 2017-07-25T19:30:45Z (GMT). No. of bitstreams: 1 Carlos Rafael Wutzki.pdf: 1863942 bytes, checksum: 92b287f4925fa1855b1c0d218fc2bb5e (MD5) Previous issue date: 2014-02-07<br>The white mold of soybean, caused by Sclerotinia sclerotiorum, is causing great damage to the soybean crop in Brazil. It is a polyphagous fungus hard to control because it produces resistance structures called sclerotia, which can remain viable in the soil for several years. Aiming its control, various management strategies should be used as the control with alternative substances, biological control agents and fungicides. Thus, nine experiments were conducted in naturally infested areas by white mold in 2011/12 season in the counties of Arapoti/PR, Mauá-da-Serra/PR and Pinhão/PR, with an experiment of alternated control, a biological control and one of chemical control conducted at each site. The variables analyzed were incidence, severity, yield and numbers of sclerotia produced. The objective of the experiments of alternative control was to assess different alternative substances, foliar sprayed, isolated or combined with the fungicide fluazinam, for control of white mold in soybean. The alternative substances applied were sodium dichloroisocyanurate, benzalkonium chloride, pyrolysis extract, sodium hypochlorite, cobalt + molybdenum, sucrose, sodium bicarbonate and acibenzolar-S-methyl. As conclusions, it was observed that alternative substances applied in combination with the fungicide fluazinam provided lower severity of white mold in soybeans on the experiment conducted in Pinhão – PR, and fungicide fluazinam applied alone or in combination with alternative substances was effective in control of white mold in soybeans in locations with high incidence of the disease. The objective of the experiments of biological control was to evaluate different biological control agents sprayed foliar compared to the untreated control and the fungicide Fluazinam for control of white mold in soybean. The biological control agents used were: Thichoderma harzianum SC; Thichoderma asperellum EC; Thichoderma asperellum WG; Coniothyrium minitans and Bacillus subtilis. As conclusion, the biological control agents were not effective in controlling white mold of soybean in the conditions that were tested, and the fungicide fluazinam demonstrated lower incidence and severity of disease and higher yield of soybean when applied in areas with high potential inoculum. Finally, the objective of the experiments of chemical control was to verify the efficiency of the control of white mold in soybeans with the use of fungicides applied alone, in rotation, at different growth stages and in a mixture of two active ingredients. The fungicides used were carbendazim, thiophanate methyl, procymidone and fluazinam. As conclusion, the use of fungicides were effective in controlling the incidence and production of sclerotia of S. sclerotiorum in soybean, especially the combinations that had two or more applications of the active ingredient Fluazinam.<br>O mofo branco da soja, causada pelo fungo Sclerotinia sclerotiorum, vem causando grandes danos na cultura da soja no Brasil. Trata-se de um fungo polífago de difícil controle, pois produz estruturas de resistência denominadas escleródios, que podem permanecer viáveis no solo por vários anos. Visando seu controle, várias estratégias de manejo devem ser utilizadas, como o controle com substâncias alternativas, agentes de controle biológico e fungicidas. Diante disso, foram conduzidos nove experimentos em áreas naturalmente infestadas pelo mofo branco na safra 2011/12 nos municípios de Arapoti/PR, Mauá-da-Serra/PR e Pinhão/PR, sendo um experimento de controle alternativo, um de controle biológico e um de controle químico conduzidos em cada local. As variáveis analisadas foram incidência, severidade, rendimento e o número de escleródios produzidos. O objetivo dos experimentos de controle alternativo foi avaliar diferentes substâncias alternativas pulverizadas via foliar, isoladamente ou em combinação com o fungicida fluazinam para o controle do mofo branco em soja. Nos experimentos de controle alternativo as substâncias utilizadas foram: dicloroisocianurato de sódio, cloreto de benzalcônio, extrato pirolenhoso, hipoclorito de sódio, cobalto + molibdênio, sacarose, bicarbonato de sódio e acibenzolar-S-metil. Concluiu-se que as substâncias alternativas aplicadas em associação com o fungicida fluazinam proporcionaram menor severidade do mofo branco na cultura da soja no experimento conduzido em Pinhão – PR e a aplicação do fungicida fluazinam isolado ou em associação com as substâncias alternativas foi eficiente no controle do mofo branco na cultura da soja nos locais com alta incidência da doença. O objetivo dos experimentos de controle biológico foi avaliar diferentes agentes de controle biológico pulverizados via foliar em comparação ao tratamento controle e ao fungicida fluazinam para o controle do mofo branco em soja. Os agentes de controle biológico utilizados foram: Thichoderma harzianum SC; Thichoderma asperellum EC; Thichoderma asperellum WG; Bacillus subtilis e Coniothyrium minitans. Conclui-se que os agentes de controle biológico não foram eficazes no controle do mofo branco da soja nas condições em que foram testados e que o fungicida fluazinam proporcionou menor incidência e severidade do doença quando aplicado em áreas com elevado potencial de inóculo. E finalmente, o objetivo dos experimentos de controle químico foi verificar a eficiência de controle do mofo branco na soja com o uso de diferentes fungicidas aplicados isoladamente, em rotação, em diferentes estádios fenológicos e em mistura de dois princípios ativos. Os fungicidas utilizados foram carbendazim, tiofanato metílico, fluazinam e procimidona. Concluiu-se que os fungicidas testados proporcionaram menores níveis de incidência e menor produção de escleródios, principalmente as combinações que possuíam duas ou mais aplicações do princípio ativo fluazinam.
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AGUIAR, Renata Alves de. "Manejo do mofo branco (Sclerotinia sclerotiorum L.) em tomateiro industrial." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/444.

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Made available in DSpace on 2014-07-29T14:52:07Z (GMT). No. of bitstreams: 1 Renata Alves.pdf: 1312984 bytes, checksum: 4ed5f4555216a682f038513b0c3af4a6 (MD5) Previous issue date: 2011-08-30<br>Brazil ranks ninth in the world production of tomato (Solanum esculentum L.), while much of this production is destined for processing industries. The added value obtained with the fruit processing endorses this species as the vegetable with the greatest economic importance in the Cerrado region of Brazil, where the State of Goiás stands out as the largest producer. Despite the favorable soil and climatic conditions, several factors have hindered its production, especially diseases caused by soilborne pathogens, which had increased their importance with the adoption of intensive production systems. Among them, white mold caused by Sclerotinia sclerotiorum (Lib.) De Bary has caused serious problems in infested soils, under mild temperatures and high humidity. Concerning the large number of S. sclerotiorum hosts and the lack of resistant hybrids, chemical control has been chosen as the most common method for disease management, despite not always efficient, due to the difficulties to reach the pathogen s resistance structures in the soil. Therefore, the study aimed to evaluate the disease escape on different tomato hybrids, to compare the effectiveness of synthetic fungicides mixed or not to potassium silicate; evaluate the biological control of white mold, with different commercial products based on Trichoderma spp. associated or not to a synthetic fungicide, and to evaluate the biological control with or without chemical fungicides, applied through chemigation. Tests were carried out in soil of medium texture at Unilever experimental farm, in Goiânia (GO), from 2008 to 2010. The experimental area was previously infested with sclerotia of the pathogen, obtained in pre-cleaning wastes of soybean. Drip irrigation was used in all tests, which had 4 plants m-1 with 1.5 meters between rows. The hybrids used in the disease escape tests were: U232, U2006 (Unilever), H9992, H7155 (Heinz), N877 (Nunhems) and H108 (Hypeel). In all other essays, Heinz 9780 was the chosen hybrid. All experiments were conducted under randomized blocks design with three replications, and had weekly assessments of disease incidence to estimate the area under the disease progress curve (AUDPC). We also evaluated the productivity and its components, as well as acidity, soluble solids content and industrial yield. The results were submitted to ANOVA and to the Scott Knott or Tukey tests at 5%, using the statistical program Sisvar. It was shown that: Hybrids H9992 and Hp108 had lower AUDPCs, suggesting a partial escape to white mold and that hybrid choice can be added to the disease management cultural practices, despite there was no difference on their yield. In 2008, under higher disease pressure, potassium silicate in plots without fungicide application showed disease incidence, AUDPC, productivity and industrial yield equivalent to treatments with fluazinam and procymidone, and superior to results with benzalkonium chloride. There was no difference between treatments with Trichoderma spp. associated or not to fluazinam, in any of the assessed traits. Regarding industrial yield, there was an interaction between Trichoderma, fluazinam and years, with higher pulp yield under higher disease incidence and fluazinam sprayed alone. It was found that biological control with Trichoderma spp. via chemigation as a single measure or in mixture with the synthetic fungicides procymidone fluazinam reduced the AUDPC and increased the productivity of processing tomatoes in 25 tons on average, compared to the control. Therefore, this study showed new options for the integrated management of white mold in processing tomatoes.<br>O Brasil ocupa o nono lugar na produção mundial de tomate (Solanum esculentum L.), sendo que grande parte desta produção é destinada a indústrias de processamento. A agregação de valor obtida com o processamento torna esta espécie a hortaliça de maior importância econômica na região do Cerrado do Brasil, onde o Estado de Goiás se destaca como maior produtor. Apesar das condições edafo-climáticas favoráveis, vários fatores têm dificultado sua produção, principalmente as doenças provocadas por patógenos habitantes do solo, que tem aumentado sua importância em sistemas de produção intensivos. Dentre elas, o mofo branco provocado por Sclerotinia sclerotiorum (Lib.) De Bary causa sérios problemas em solos infestados, sob condições de temperatura amena e alta umidade. Por ser um patógeno polífago e não existirem híbridos resistentes, o controle químico tem sido o método mais utilizado no manejo da doença, apesar de nem sempre ser eficiente pela dificuldade de atingir as estruturas de resistência do patógeno no solo. Dessa forma, este trabalho teve como objetivo avaliar diferentes híbridos quanto à arquitetura da planta para escape da doença; comparar a aplicação de fungicidas sintéticos com e sem a utilização de silício; avaliar o controle biológico do mofo branco por meio de diferentes produtos comerciais elaborados a partir de isolados do fungo Trichoderma spp., associados ou não com a aplicação de fungicida sintético, via barra de pulverização ou via fungigação. Foram conduzidos ensaios na fazenda experimental da Unilever, em Goiânia (GO), nos anos de 2008 a 2010, em solo de textura média. A área experimental foi previamente infestada com escleródios do patógeno, obtidos em resíduos de pré-limpeza de soja. A irrigação em todos os experimentos foi realizada por gotejamento em parcelas com estande de 4 plantas m-1 com 1,5 metro entre linhas. Os híbridos utilizados para avaliação quanto à arquitetura da planta foram: U232, U2006 (Unilever), H9992, H7155 (Heinz), N877 (Nunhems) e Hp108 (Hypeel). Já o híbrido utilizado nos demais ensaios foi o Heinz 9780. Todos os experimentos foram conduzidos sob delineamento experimental de blocos ao acaso, com três repetições, e tiveram avaliações semanais da incidência da doença para obtenção da área abaixo da curva de progresso da doença (AACPD). Avaliou-se ainda a produtividade e seus componentes, além de pH, teor de sólidos solúveis e rendimento de polpa. Os resultados foram submetidos à ANOVA e ao teste de Scott-Knott ou Tukey (5%) com auxílio do programa estatístico Sisvar. Verificou-se que: Em ambos os anos, a menor AACPD nos híbridos H9992 e Hp108 (Scott-Knott 5%), é creditada ao escape parcial da doença, devido ao porte das plantas e concentração de maturação, demonstrando que a escolha do híbrido pode ser adicionada às práticas culturais já utilizadas para o manejo da doença. Apesar de não ter havido diferenças entre os híbridos quanto à sua produtividade, as perdas na produção foram correlacionadas à incidência da doença e à AACPD. Em ano com elevada incidência os fungicidas (fluazinam e procimidona) são eficientes e silicato de potássio, sem aplicação de fluazinam ou procimidona, foi igualmente eficiente, podendo ser utilizado na agricultura orgânica. No controle do mofo branco, via barra de pulverização, na cultura do tomate para processamento industrial, o uso do Trichodermax e Trichodermil não diferiram do padrão de controle em relação a incidência da doença, produtividades e rendimentos. Não há influência do fluazinam via barra de pulverização no controle do mofo branco. Já para o rendimento de polpa há interação entre Trichoderma, ano e fluazinam, sendo que ocorreu um maior rendimento de polpa no ano de maior incidência com o uso do fluazinam. Verificou-se que o controle biológico com utilização do Trichoderma sp., via fungigação, para o mofo branco, isolado ou em combinação com os fungicidas sintéticos fluazinam e procimidona, reduz a AACPD e incrementa a produtividade do tomate para processamento industrial em até 25 toneladas ha-1 em média. O rendimento de polpa nos tratamentos com controle biológico foi aumentado em cerca de 1,0 e 7,0 t ha-1, respectivamente, em 2009 e 2010.
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39

GIANNINI, Laila Santos Vieira. "Sclerotinia sclerotiorum (mofo branco): avaliação das propriedades mutagênicas in vivo." Universidade Federal de Alfenas, 2016. https://bdtd.unifal-mg.edu.br:8443/handle/tede/895.

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A produção de culturas de feijão, soja, algodão, batata, girassol, vêm sofrendo perda de até 70% ocasionada pelo fungo de solo denominado mofo-branco, da espécie Sclerotinia sclerotiorum, filamentoso e necrotrófico. Esse fungo na forma de escleródio apresenta-se como grânulo que se confunde com os grãos nas etapas de colheita e limpeza, podendo chegar ao consumidor final. Entretanto, ainda não são conhecidas as consequências do consumo desse fungo na forma de escleródios nos alimentos que são base da alimentação humana. Assim, a presente proposta visa o maior conhecimento da composição e aspectos toxicológicos desse fungo tão comum nos principais produtos agrícolas disponibilizados para o consumidor. Para identificação de solventes adequados à extração de compostos dos escleródios foram realizados testes cromatográficos que apontaram a escolha do acetato de etila para produção do extrato. Foram preparadas rações fúngicas contendo 6, 60 e 600 mg do extrato em 100g de ração, resultando num consumo de 25, 240 e 2600 mg de extrato por kg de peso corpóreo. No estudo in vivo, o consumo de ração fúngica não causou alterações nutricionais nos animais. O teste de cometa apresentou aumento no comprimento da cauda de cometas em 106,34; 174,77 e 131,90% para sangue; aumento de Tail Moment de 166%, 380% e 271% (linfócitos) e 660%, 639% e 429% (fígado) e aumento de 129%, 212% e 160% (linfócitos) e 284%, 296% e 260% (fígado) no % de DNA na cauda. Os testes de micronúcleos de medula óssea e cólon apresentaram aumento da frequência de micronúcleos em 186,95%; 147,82%; 239,13% para eritrócitos e 202,63; 173,68 e 223,68% em células do cólon. Este resultado também foi significativo para o teste de apoptose demonstrando aumento de 568,88, 457,77e 513,33% no numero de células apoptóticas. Estes resultados demonstram a ação mutagênica de escleródios do fungo Sclerotinia sclerotiorum, que podem ser desde a quebra do DNA, quanto a alterações nas fibras do fuso ou rearranjos cromossômicos associados ou não a fragmentação do DNA. Esses aspectos tornam os escleródios compostos que devem ser alvo de mais estudo sobre esses efeitos lesivos, uma vez que os mesmos podem chegar ao consumo alimentar de homens e animais por meio de alimentos e rações contaminadas, respectivamente.<br>The crop of soybean, beans, canola, cotton, peas, lettuce, potatoes, currently represent one of the most important agricultural activities in Brazil. These crops have been threatened, leading to losses of up to 70% of its total volume by the presence of soil fungus called popularly white mold or rot soil, the species Sclerotinia sclerotiorum. This fungal species is characteristic to be filamentous and cause necrosis in their hosts, and often find themselves in the granules form (sclerotia) which mix themselves with the seeds in the stages of harvesting and cleaning, thereby they can reach the final consumer in batches containing up to half of its grains contaminated by dormant mycelium of the fungus For identification of suitable solvents for extraction of compounds of sclerotia chromatographic tests were performed which indicated the choice of ethyl acetate to extract production. fungal diets containing 6, 60, and 600 mg of extract in 100 g of feed were prepared, resulting in a consumption of 25, 240 and 2600 mg of extract per kg body weight. In the in vivo study, the consumption of fungal feed caused no nutritional changes in animals. The comet test showed an increase in the length of comet tail 106,34; 174.77 and 131.90%. in blood; increase of Tail Moment 166%, 380% and 271% (lymphocytes) and 660%, 639% e 429% (liver) and increase of 129%, 212% and 160% (lymphocytes) and 284%, 296% and 260% (liver) in % of DNA in tail. Micronucleus tests in bone marrow and colon showed increased micronuclei frequency 186.95%; 147.82%; 239.13% to 202.63 and erythrocytes; 173.68 and 223.68% in colon cells. This result was also significant for apoptosis test showing increased 568.88, 513.33 457,77e% in the number of apoptotic cells. These results demonstrate the mutagenic action of sclerotia of Sclerotinia sclerotiorum, which may be from the DNA breakage, as changes in spindle fiber or chromosomal rearrangements associated or not with DNA fragmentation. These aspects render the compounds sclerotia that should be subject to further study on these damaging effects, as they can reach the food intake of humans and animals through contaminated food and feed, respectively.and the other half mixed with the sclerotia.<br>Fundação de Amparo à Pesquisa do Estado de Minas Gerais - FAPEMIG
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40

Arruda, Josicléa Hüffner. "Ação de agroquímicos no controle de mofo branco em soja." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/759.

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A soja é uma das principais commodities produzidas no mundo. Entretanto, tem sua produtividade reduzida, significativamente, devido às doenças, dentre estas o mofo branco, causado pelo fungo Sclerotinia sclerotiorum, com expressiva severidade em regiões de clima ameno e úmido. O controle da doença, incluindo o uso de fungicidas, é pouco eficiente. Assim, o trabalho teve por objetivo avaliar a eficiência de herbicidas e adubos foliares à base de fosfito de potássio no manejo do mofo branco em soja, bem como a ação dos produtos, indução da síntese de fitoalexinas e das enzimas peroxidases e superóxido dismutase, assim como a ação direta dos agroquímicos sobre o patógeno. Para isso, avaliou-se a ação in vitro dos produtos químicos sobre o crescimento micelial do fungo e germinação de escleródios. A indução foi testada em laboratório por meio da avaliação da síntese de fitoalexinas em cotilédones de soja, e das enzimas POX e SOD, submetidas aos mesmos tratamentos de campo. O experimento de campo foi implantado em Coronel Domingos Soares - PR, safra 2012/2013, em área com infestação natural do fitopatógeno. O delineamento experimental foi de blocos ao acaso, com 4 repetições e 6 tratamentos: testemunha, lactofen (0,6 L ha-1 em V4), bentazon (1,5 L ha-1 em V4), fluazinam (1 L ha-1 em R1) e dois adubos foliares denominados fosfito A (30 p/p % de P2O5 e 20 p/p % de K2O) (3 L ha-1 em V4 + R1) e fosfito B (26 p/p % de P2O5 e 19 p/p % de K2O) (2 L ha-1 em V4 + R1). O fungicida foi o único produto que inibiu totalmente o desenvolvimento do fungo in vitro. Em laboratório, o bentazon alcançou os maiores índices de produção de fitoalexinas, enquanto os adubos foliares não as induziram. Ambos os herbicidas e o fosfito A tiveram potencial para aumentar a atividade da enzima POX. No experimento de campo os herbicidas bentazon e lactofen destacaram-se no controle do mofo branco, sendo de 60,5% e 52,3%, respectivamente, e o tratamento com fosfito A com um controle de 37,9%, superiores ao tratamento com fungicida. Em relação aos componentes de rendimento houve incrementos utilizando os herbicidas, entretanto, não diferiram estatisticamente da testemunha pelo teste de Duncan a 5%.<br>Soybean is one of the most important crops in the world. However, several times the yield is reduced due to diseases as the stem rot (white mold) caused by Sclerotinia sclerotiorum, which is a several fungal, mainly in areas with low temperatures and high moisture. The disease control, including the use of fungicides, is difficult. Thus, the objective of this study was to verify the effect of herbicides and foliar fertilizers with potassium phosphite on control of white mold soybean, determining the action of this agrochemicals about the phytoalexin, superoxide dismutase and peroxidase synthesis, and the direct action on the pathogen. For this, the in vitro effect of agrochemicals on the pathogen was evaluated. Also, the induction was tested in the laboratory by evaluation of phytoalexin synthesis in soybean cotyledons, and POX and SOD enzymes, subjected to the same treatment field. The field trials were conducted in Coronel Domingos Soares – PR, evaluations were made in 2012/2013 crop. A randomized-complete blocks design with 6 treatments and 4 replicates was used. The treatments were: lactofen (0,6 L ha-1 applied in V4), bentazon (1,5 L ha-1 in V4), fluazinam (1 L ha-1 in R1) and two foliar fertilizers called fosfito A (30 p/p % de P2O5 and 20 p/p % de K2O) (3 L ha-1 in V4 + R1) and fosfito B (26 p/p % de P2O5 and 19 p/p % de K2O) (2 L ha-1 in V4 + R1). . The fungicide was the only product that completely inhibited fungal growth in vitro. In the laboratory, the bentazon reached the highest levels of phytoalexin production, but the foliar fertilizers did not induce the production of the same. Both herbicides and phosphite A had the potential to elicit the production of peroxidase enzyme. In field experiments the herbicides bentazon and lactofen stood out in the control of white mold, being 60.5% and 52.3% respectively, and treatment with the fosfito A provided a control of 37.9%, being superior to the treatment with fungicide. Regarding the grain fields compounds had increase using the herbicides, but did not differed from the control by Duncan test at 5%.
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41

Yuan, Hongye. "Growth of Metal Organic Frameworks (MOFs) layers on functionalized surfaces." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX058/document.

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Dans ce travail, nous étudions les conditions de synthèse pour la croissance directe des MOF Fe3 + / H2BDC et Fe3 + / H2NDC sur des surfaces de silicium fonctionnalisées (111) présentant une structure bien définie et dont la chimie de surface peut être adaptée pour favoriser / diriger la nucléation et la croissance hétérogènes Des MOF. Le mécanisme de croissance des MOF pertinents aux conditions choisies et les propriétés flexibles des cadres MIL-88B et MIL-88C sont également présentés avec l'aide des résultats du traitement post-synthèse.En ce qui concerne le système de morphologies et structures Fe3 + / H2BDC, les structures des couches obtenues dépendent fortement de la chimie de surface des monocouches greffées et aussi des conditions de synthèse (température, composition de la solution et temps de réaction). Les cristaux MIL-88B orientés sur la direction [001] sont seulement observés sur des surfaces fonctionnalisées par COOH et se sont révélés être favorisés en présence d'un excès de ligand en solution. La formation de la phase MIL-101 texturée le long de la direction [111] sur les surfaces de Si pyridyl et hydroxy-terminé est observée indépendamment de la condition de synthèse. Des cristaux MIL-101 isolés avec une orientation préférée le long de la direction [111] ont également été trouvés sur une surface terminée par acide à un excès de métal, alors que les îlots MIL-101 orientés au hasard sont observés au rapport R ≧ 1. Au contraire, aucune croissance du film ne s'est produite sur les surfaces de Si à terminaison méthyle. L'introduction de HCl, de H2O et de base faible organique -triéthylamine dans les solutions précurseurs affecte également la formation de films MOF avec différentes morphologies et couverture entre MIL-101 et MIL-88B sur des surfaces de Si à terminaison carboxylique. La dépendance temporelle de la croissance du film à un excès de ligand (R = 2) et d'un excès de métal (R = 0,5) sans et avec addition de HCl indique clairement que les deux MIL-88B et MIL-101 suivent un mode de croissance Volmer-Weber, Au cours de laquelle, des cristaux ou des grappes tridimensionnels isolés se sont formés à l'étape initiale et se sont développés latéralement et verticalement à la surface.En ce qui concerne le système de Fe3 + / H2NDC, en fonction des conditions de synthèse, y compris la température, le rapport du ligand à la concentration [Fe3 +] et [Fe3 +] seulement une phase-MIL-88C avec une couverture de surface variable allant des cristaux hexagonaux séparés aux couches composées d'isolés On a observé des faisceaux de cristallites hexagonales tous avec une orientation préférentielle le long de la direction. L'évolution des cristaux de MIL-88C avec le temps de cristallisation suggère également un mode Volmer-Weber.Les mesures ex-situ XRD du post-traitement vers les couches synthétisées constituées de MIL-88B et MIL-88C démontrent respectivement leur flexibilité lors de la désorption des molécules. Les mesures provisoires de la XRD in situ montrent également la réversibilité du cadre MIL-88C lors de l'absorption et de la libération de l'éthanol<br>Within this work we investigate synthesis conditions for the direct growth of Fe3+/H2BDC and Fe3+/H2NDC MOFs onto functionalized silicon (111) surfaces exhibiting well-defined structure and whose surface chemistry can be tailored in order to favor/direct the heterogeneous nucleation and growth of the MOFs. Growth mechanism of relevant MOFs at chosen conditions and flexible properties of MIL-88B and MIL-88C frameworks are presented as well with the assistance of post-synthesis treatment results.Regarding the system of Fe3+/H2BDC morphologies and structures of obtained layers strongly depend both on surface chemistry of grafted monolayers and also on the synthesis conditions (temperature, solution composition and reaction time). Oriented MIL-88B crystals along [001] direction is only observed onto COOH-functionalized surfaces and was found to be favored in presence of ligand excess in solution. The formation of textured MIL-101 phase along [111] direction on pyridyl and hydroxyl terminated Si surfaces is observed irrespective of the synthesis condition. Isolated MIL-101crystals with preferred orientation along [111] direction was also found on acid terminated surface at excess of metal, whereas randomly oriented MIL-101 islands are observed at ratio R≧1. In contrary, no film growth happened on methyl terminated Si surfaces. Introduction of HCl, H2O and organic weak base-triethylamine into the precursor solutions also affects the formation of MOF films with various morphologies and coverage between MIL-101 and MIL-88B on carboxylic terminated Si surfaces. Time dependence of film growth at excess of ligand (R=2) and at excess of metal (R=0.5) without and with addition of HCl indicates clearly that both of MIL-88B and MIL-101 follows a Volmer-Weber growth mode, during which, isolated three-dimensional crystals or clusters formed at initial stage and grew both laterally and vertically on the surface.As to the system of Fe3+/H2NDC, depending on the synthesis conditions including temperature, ratio of ligand to [Fe3+] and [Fe3+] concentration only one phase-MIL-88C with variable surface coverage ranging from separated hexagonal crystals to layers composed of isolated bundles of hexagonal crystallites all with preferential orientation along [001] direction was observed. Evolution of MIL-88C crystals along with crystallization time also suggests a Volmer-Weber mode.Ex-situ XRD measurements of post-treatment towards the as-synthesized layers comprised of MIL-88B and MIL-88C respectively demonstrate their flexibility during molecule desorption. Tentative in-situ XRD measurements also show the reversibility of MIL-88C framework upon ethanol uptake and release
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42

Abeykoon, Brian. "Conception, synthèse et caractérisations de MOFs à base de porphyrines." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1259/document.

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Les porphyrines sont des composés macrocycliques naturels étudiés de manière approfondie en tant que mimétiques enzymatiques ou catalyseurs d'oxydation en milieu homogène. L'incorporation de porphyrines dans des réseaux de polymères de coordination métal-organique (MOFs), qui constituent une famille de composés cristallins poreux connus pour leur diversité structurelle, pourrait conduire à des matériaux constitués de réseaux étendus présentant les mêmes propriétés que les systèmes homogènes. Toutefois de nombreux travaux ont montré que la limitation majeure pour des applications à grande échelle des MOFs est leur stabilité.La stabilité de ces matériaux peut être accrue en employant des cations métalliques de valence élevée dans l'unité de construction inorganique (tels que Fe3+, Al3+, Zr4+) et / ou en modifiant la fonction coordinante du ligand organique.Ce travail est relatif à l'étude de la réactivité de ligands porphyriniques portant diverses fonctions coordinantes, avec des ions métalliques de valence élevée. L'influence des paramètres de synthèse et la caractérisation approfondie de ces MOFs ont été réalisées par une combinaison de techniques expérimentales (diffraction des rayons X, analyse thermogravimétrique, spectroscopie UV-vis, spectroscopie infrarouge, études de sorption, etc.). Dans un premier temps, l'étude s'est focalisée sur des MOFs porphyriniques à base de groupements carboxylates stables connus, ce qui a conduit à de nouvelles variantes de ces matériaux. Dans un second temps il est démontré que les topologies des réseaux observées sur un ligand porphyrinique à base carboxylate peuvent être étendues à d'autres fonctionnalités avec la synthèse d'un nouveau MOF à base de tétrazolate. L'amélioration de la stabilité a également été explorée avec des ligands portant des fonctions phénol qui ont abouti à l'élaboration de nouveaux réseaux de coordination. La synthèse et l'étude de stabilité d'un MOF porphyrinique à base de gallate est rapportée. L'évaluation préliminaire de l'activité catalytique de certains des MOFs élaborés est également décrite<br>Porphyrins are important macrocyclic compounds which are prevalent in nature and have been extensively studied by chemists in homogeneous catalysis as enzyme mimics. Incorporating porphyrins in metal-organic frameworks (MOFs) offer an ideal opportunity to obtain material with extended frameworks possessing the same properties as the homogenous systems. Much work has been done on porphyrinic MOFs but their stability remains a problem and a major limitation for possible wide scale applications. In literature, more stable MOFs have been realised using high valent metal ions in the inorganic building unit (such as Fe3+, Al3+, Zr4+) and/or by using more basic functionalities in the organic linker. However, regarding porphyrinic MOFs, little work is reported with ligands based on functionalities other than carboxylic acid groups. Therefore, our work focused on investigating the reactivity of porphyrinic ligands carrying various functionalities with high valent metal ions. More precisely, we focused on the design, synthesis optimisation and characterisation of such materials. This included studying existing stable carboxylate porphyrinic frameworks with a goal of incorporating new functionalities, which led to new variations of these materials. Our work also demonstrated that the framework topologies observed with carboxylate based porphyrinic ligand can be expanded to other functionalities with the synthesis of a new tetrazolate based porphyrinic MOF. MOF synthesis was also investigated with phenolate functionalised ligands and resulted in the first gallate based porphyrinic MOF reported. The stability of this new material was assessed. This manuscript discusses the synthesis and the characterisation of these MOFs via a combination of experimental techniques (X-ray diffraction, TGA analysis, UV-vis spectroscopy, IR-spectroscopy, sorption studies etc.). The preliminary evaluation of the catalytic activity of some of the MOFs is also described
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43

Nicolau, Marco. "Separação dos Isómeros de Xileno em Metal-Organic Frameworks - MOFs." Master's thesis, Instituto Politécnico de Bragança, Escola Superior de Tecnologia e de Gestão, 2008. http://hdl.handle.net/10198/1718.

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A separação dos isómeros de xileno é um problema clássico da indústria petroquímica devido à sua ligação directa à produção de PET. A destilação é uma das formas possíveis de remover o o-xileno, mas falha para os restantes alquilaromáticos devido aos pontos de ebulição serem muito próximos. Além da cristalização, a qual possui uma pobre eficiência, a adsorção é largamente usada, sendo operado industrialmente em leito móvel simulado (SMB). Como adsorventes nesses processos são usados os zeólitos X e Y, permutados com catiões, tal como o Na+, K+ e Ba2+. Os metal-organic frameworks (MOFs) são uma nova classe de materiais cristalinos e recebem actualmente bastante interesse devido às suas potencialidades para serem aplicados como adsorventes. O carácter maioritariamente orgânico da superfície interna dos MOFs oferece um potencial sem precedentes para melhorar e ajustar a afinidade para adsorbatos aromáticos. Este trabalho representa um dos primeiros estudos acerca do uso de MOFs na separação por adsorção em fase gasosa dos isómeros de xileno. Neste trabalho, apresenta-se um estudo detalhado do equilíbrio de adsorção mono- e multicomponente dos isómeros de xileno e do etilbenzeno no MOF Zn(BDC)(Dabco)0:5. Os resultados obtidos, indicam que o MOF em estudo apresenta duas categorias de sítios activos de adsorção e que a forma como as moléculas se empacotam na estrutura microporosa do sólido pode ser determinante na separação. Além da baixa selectividade, o valor elevado das entalpias de adsorção, comparativamente aos zeólitos, é prejudicial do ponto de vista da operação de processos adsorptivos. The separation of mixed C8 alkylaromatic compounds is one of the most challenging issues in the chemical industry because of its direct link with PET manufacture. Distillation is only feasible for the removal of o-xylene; it fails for the other C8 alkylaromatic compounds because of the similarity of their boiling points. Besides crystallization, which has a poor efficiency, adsorption is widely used and is operated industrially in simulated moving bed processes. Zeolites X and Y exchanged with cations such as Na+, K+ e Ba2+ are used in such processes. Metal-organic frameworks (MOFs) are a new class of microporous crystalline materials and currently receive much attention in regard to adsorption applications. The mainly organic character of the inner surface of MOFs offers unprecedented potential for enhancing and fine-tuning the affinity for aromatic adsorbates. This work represents one of the first uses of MOFs in the separation by adsorption of xylene isomers under vapor conditions. This work reports a detailed experimental study of single and multicomponent adsorption equilibrium of xylene isomers and ethylbenzene in the MOF Zn (BDC)(Dabco)0:5. The results arising from this study lead us to conclude that the MOF has two categories of adsorption sites and that the stacking of the molecules in the microporous structure is crucial in the separation. Besides the poor selectivity, the high value of the adsorption enthalpy of aromatics in this MOF, in comparison to zeolites, is not beneficial with respect to the operation of adsorption processes.
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44

Müller, Tobias. "Untersuchungen zum „Controlled SBU Approach“ an metall-organischen Gerüstverbindungen und Syntheseversuche metallsubstituierter MOF-5- und MOF-177-Homologer." Master's thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2012. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-89799.

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Die potentiellen Precursor Magnesiumoxobromid bzw. Mangan(II,III)-oxopivalat für die noch unbekannten metallsubstituierten IRMOF-Homologen MOF-5(Mg) bzw. MOF-5(Mn) konnten erfolgreich synthetisiert und Charakterisiert werden. Deren experimenteller Einsatz zur Synthese der IRMOF-Homologen schlug jedoch fehl. Es konnte gezeigt werden, dass unter den klassischen CSA-Reaktionsbedingungen sowie unter modifizierten Parametern keine Synthese der IRMOF-Homologen möglich ist. Diese Feststellung wurde mit der Diskussion um die Eigenschaften der Komplexe, der Metallionen sowie mit einer Aufarbeitung der dazu zugänglichen Literatur begründet. Es ist mit der Synthese der neuen MOF-177-Homologen MOF-177(Co) und MOF-177(Be) gelungen, die bereits bei MOF-5-Homologen eingesetzten Precursor und Parameter auf ein System anzuwenden, das nicht zu den Yaghi\\\\\\\\\\\\\\\'schen IRMOFs gehört. Die Festkörper weisen mit ihren Oberflächenwerten SBET(MOF-177(Co)) = 3742 m²/g bzw. SBET(MOF-177(Be)) = 1816.4 m²/g klar mikroporöses Adsorptionsverhalten auf. Eine erste vereinfachte Anpassung der Kristallstrukturen an die experimentellen PXRDs konnte für beide MOFs vorgenommen werden. MOF-177(Co) zeigt wie auch MOF-5(Co) eine leicht vergrößerte Gitterkonstante. MOF-177(Be) konnte aufgrund der Verdrehung der Carboxylatgruppen am Berylliumoxocluster ausschließlich in röntgenamorpher Form hergestellt werden. Die Untersuchung der auftretenden Co-Spezies in reinen und mit Zinkprecursor gemischten Lösungen an Cobaltoxopivalat in den Lösungsmitteln Toluol brachte folgende Erkenntnisse: • Der im Feststoff dimere achtkernige Cobaltprecursor zerfällt während des Lösens in die vierkernige monomere Form und ist strukturanalog dem basischen Zinkcarboxylaten (Typ I). • Der Komplex unterliegt einem solvensabhängigem Komplexstabilitäts-gleichgewicht. Dieses ist aufgrund der koordinierenden Eigenschaften des DEF, in den DEF-Lösungen weiter in Richtung der Zersetzungsprodukte verschoben. In beiden Lösungen ist der Komplex zu über 90% undissoziiert. • Nur in DEF treten bei dem Zumischen verschiedener Zinkprecursor Metallaustauschreaktionen auf. Es ist somit die Existenz von vierkernigen Zn-Co-Mischclustern der allg. Form [CoyZn(4-y)O] bewiesen worden. • Es wurde nachgewiesen, dass beim Vorhandensein von Acetat und Pivalat Anionenaustauschreaktionen stattfinden und Komplexe der Form [CoyZn(4-y)O(Piv)xAc(6-x)] auftreten. Die Bedeutung für das Stattfinden des CSAs unter Berücksichtigung der empirischen Erkenntnisse aus der Literatur wurde erörtert.
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45

Klinkebiel, Arne [Verfasser]. "Linker-Synthese und postsynthetische Modifikation von MOFS - Triazin-, Stilben- und Biphenyl-basierte Strukturen zur Darstellung funktionalisierter MOFs und zur postsynthetischen Implementierung von Wasserstoffbrückenmustern / Arne Klinkebiel." Kiel : Universitätsbibliothek Kiel, 2016. http://d-nb.info/1104733706/34.

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46

Ayala, Hernández Abraham. "Janus-type and Molecular MOF-based composites." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/461179.

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La presente Tesis está enfocada al estudio, desarrollo e implementación de nuevas metodologías de síntesis de estructuras metal-orgánicas (MOFs) basadas en compuestos multifuncionales. El trabajo de investigación de esta Tesis se desarrolló en dos líneas de investigación: i) por un lado, la síntesis de partículas metálicas Janus con MOFs y su funcionalización parcial para aplicaciones en eliminación de metales pesados, aplicaciones de auto movilidad y fluorescencia, ii) por otro lado la incorporación de moléculas activas en MOFs a través de la creación controlada de defectos, estudiando la formación del MOF así como su posible aplicación en eliminación de metales pesados En el capítulo uno, nosotros revisamos la evolución en el campo de los MOFs a partir de un desarrollo histórico, y la presentación de las principales estrategias de síntesis, así como las propiedades y aplicaciones. También, nosotros presentamos especial atención en las metodologías actuales para la miniaturización de MOFs, las mejoras en las propiedades y posibles aplicaciones. También mencionamos la importancia de las posibilidades de crear compuestos de MOF combinando las propiedades intrínsecas de MOFs y otros materiales funcionales, por ejemplo, materiales magnéticos, materiales fluorescentes y catalíticos. En el capítulo dos, se describen los objetivos de la Tesis. En el tercer capítulo, se presenta el trabajo llevado a cabo en la síntesis de partículas de tipo Janus basados en MOFs. Una vez introducidos los conceptos de partículas de tipo Janus y la manera de sintetizados se presenta el trabajo experimental llevado a cabo. Este trabajo se basa en la evaporación controlada y selectiva de metales sobre parte de la superficie de MOFs. Esta metodología novedosa se organiza en diferentes pasos: i) Síntesis de MOFs nanoscópicos de tamaño controlado, ii) Deposición controlada en superficie de una monocapa de nanocristales de MOF dispersos, iii) Evaporación sobre las monocapas de nanocristales de MOFs de nanocapas de metal, iv) Separación de las superficies de los MOFs y obtención de las nanopartículas de Janus. La versatilidad de esta metodología nos ha permitido sintetizar diferentes compuestos de partículas Janus metal@MOFs, así como evaluar las propiedades magnéticas, fluorescentes, y catalíticas. En el capítulo cuatro se describe otro de tipo de composites basados en MOFs y moléculas orgánicas funcionales. Este estudio consiste en introducir moléculas orgánicas funcionales creando defectos dentro de la estructura. En particular, se ha estudiado la capacidad de insertar la molécula xylenol orange; molécula con grupos coordinantes fuertes de tipo carboxílato con capacidad de capturar metales pesados. Se ha estudiado el mecanismo de incoprporación del XO dentro del MOF y su influencia en la formación del MOF, sus propiedades finales y la capacidad de eliminación de metales pesados del composite final fueron evaluados.<br>The present Thesis has been dedicated to the study, development, and implementations of new methodologies synthesize Metal Organic Frameworks (MOFs) based multifunctional composites. Accordingly, two main lines of work can be distinguished through the lecture of this Thesis: i) the synthesis of Janus metal@MOFs particles and their partial functionalization for applications in removal of heavy metal ions, application in self-propelled and fluorescence; ii) the incorporation of active molecules into the MOFs through of creating controlled defects, and the use of the resulting composites in the removal of heavy metal ions. In the Chapter 1, we review the evolution of the field of the MOFs including a brief historical introduction and the presentation of the main synthetic routes, properties and applications. We pay special attention to the current methodologies to synthesis MOFs and their miniaturization and their improvements of their properties and their possible applications. We mention the importance of the possibilities as well to create MOF composites combining the intrinsic properties of MOFs and other functional materials (i.e. magnetic materials, fluorescence, catalytic). In Chapter 2, cites the general and specific objectives of this PhD Thesis. Chapter 3 describes the methodology used for the synthesis of Janus metallic@MOFs particles. This methodology is based on the selective evaporation of metallic components on the MOFs surfaces and is carried out in different steps: i) synthesis of MOFs and their control size; ii) fabrication of MOFs monolayers on surfaces through the controlled deposition based on solvent evaporation; iii) evaporation of metal components through the electron bean evaporation technique, iv) detachment of the MOFs from the surfaces obtaining the Janus metallic@MOFs nanoparticles. The versatility of this methodology has allowed us to synthesis different MOF based composites, and in addition, we present the magnetic, fluorescence and catalytic properties that were evaluated in different Janus metallic@MOFs nanoparticles. In chapter 4, we explored another kind of composites based on the combination of MOFs and organic functional molecules. We studied the incorporation of functional molecules into the MOFs creating defects into the network of the MOFs. In particular, we evaluated the incorporating of Xylenol Orange (XO) that has coordinative carboxylic groups and a strong capacity to chelate heavy metal ions. We studied the mechanism of the integration of XO into the MOF and their influence on the formation of the MOF, and in addition, we evaluated the final properties and specially the capacity to remove heavy metal ions.
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47

Nelson, Jocienne N. "Overtone Spectroscopy of Hydrogen in MOF-5." Oberlin College Honors Theses / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1402427206.

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48

Gandara-Loe, Jesús. "Large versatililty of metal-organic frameworks (MOFs) in gas/liquid adsorption processes." Doctoral thesis, Universidad de Alicante, 2020. http://hdl.handle.net/10045/115204.

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La tesis Doctoral está dividida en dos grandes bloques: el primero relacionado con el estudio estructural y de flexibilidad de distintos "Zeolític imidazolate fremewroks (ZIFs) utilizando distintas técnicas de caracterización de alta resolución y, además, simulación molecular; así como el efecto en la adsorción de distintas moléculas en fase gas. El segundo bloque hace referencia al estudio de MOFs en aplicaciones biomédicas, en específico en el estudio de adsorción y liberación en fase líquida de fármacos para el tratamiento del glaucoma.
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49

Henschel, Antje. "Untersuchungen zur Flüssigphasenadsorption an Metall-Organischen Gerüstverbindungen und deren Anwendung als Trägermaterialien in der katalytischen Hydrierung." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-78694.

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Im Hinblick auf eine spätere Anwendung als Katalysatorträger in Hydrierungsreaktionen wurden in dieser Arbeit Adsorptionseigenschaften von Metall-Organischen Gerüstverbindungen (MOFs) in der Flüssigphasenadsorption untersucht. In den Experimenten wurden Materialien gegenübergestellt, bei denen entweder freie Koordinationsstellen am Metallatom (MIL 101, DUT 9, HKUST 1) oder eine abgeschlossene Koordinationssphäre (MOF 5, Zn4O(btb)2, Zn2(bdc)2dabco, ZIF 8, DUT 4, DUT 6) in der Struktur vorlagen. Die Substrate und Lösungsmittel wurden hinsichtlich auf die spätere Verwendung als Edukte in der Hydrierungsreaktion ausgewählt. Neben dem polaren Zimtsäureethylester kamen unpolare Substrate wie Styrol, cis-Cyccloocten und Diphenylacetylen zum Einsatz. Die Materialien wurden desweiteren auf ihre Eignung und Stabilität in der Flüssigphasenhydrierung getestet. Da die untersuchten Metall-Organischen Gerüstverbindungen selbst nicht hydrieraktiv sind, wurden sie als Matrix für die Synthese von Palladium-Nanopartikeln (mittels Incipient Wetness Infiltration) verwendet. Als Referenzkatalysatoren kamen kommerziell erhältliche Pd-Trägerkatalysatoren (Pd@C, Pd@NoritA) und Pd@MOF 5 zum Einsatz. Bei den Experimenten erwies sich Pd@MIL 101 als besonders stabil gegenüber den Reduktions- und Reaktionsbedingungen, sowohl in Gasphasen- als auch Flüssigphasenhydrierungen. Die erzielten Ergebnisse zeigen den starken Einfluss des spezifischen Porenvolumens, der Form der Pore bzw. des Poreneingangs, der Polarität des Substrates und des verwendeten Lösungsmittels auf die adsorbierte Substratmenge. Sie verdeutlichen die Relevanz von Adsorptionsuntersuchungen an neuen Materialien. Das Verständnis der Wechselwirkungen zwischen den verwendeten Lösungsmitteln, Substraten und Adsorbentien ist ein entscheidender Faktor bei der Optimierung von Adsorptionsprozessen und bei der Verwendung von MOFs in heterogen katalysierten Reaktionen. Diese Arbeit zeigt das hohe Potential von Metall-Organischen Materialien im Bereich der heterogenen Katalyse. Unter Verwendung dieser Verbindungen als Trägermaterialien für Palladium können sehr hohe Aktivitäten in Hydrierungsreaktionen erreicht werden, welche z.T. auch industriell genutzte, Aktivkohle basierte Pd-Trägerkatalysatoren übertreffen.
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50

Permyakova, Anastasia. "Matériaux à base de solides hybrides poreux de type MOFs pour le stockage intersaisonnier d’énergie solaire." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV031/document.

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L’évolution rapide des technologies de stockage d’énergie requiert la mise en point de nouveaux matériaux plus performants afin d’utiliser l’énergie relative à l’adsorption d’un fluide (eau) pour restituer l’énergie solaire préalablement stockée sur une période courte (heures) ou prolongée (inter saisonnière). Ces matériaux sont des sels inorganiques (chimisorption de l’eau), des adsorbants physiques ou des composites (sel inorganique dans une matrice poreuse).Les polymères de coordination poreux (PCPs) ou ’Metal-Organic Frameworks‘ (MOFs) sont des solides poreux hybrides dont la structure cristalline résulte de l’association de ligands organiques polycomplexants et de briques inorganiques interagissant par liaisons fortes. Les MOFs présentent une plus grande diversité chimique et structurale par rapport aux solides poreux inorganiques, ce qui permet de varier ‘à la carte’ leur caractère amphiphile, leur volume poreux, la taille et la forme des pores.Dans le cadre de cette thèse, nous avons étudié en premier lieu une série de MOFs poreux et stables dans l’eau, construits à partir des cations métalliques à haut degré d’oxydation (Fe3+, Al3+, Cr3+, Ti4+, Zr4+) et de ligands polycarboxylates. Nous avons choisi cette série de MOFs en tant qu’adsorbants physiques tout en évaluant dans un second temps leur capacité en tant que matrices d’immobilisation de sels inorganiques.L’étude des propriétés d’adsorption d’eau des MOFs seuls a démontré leurs grandes capacités d’adsorption conduisant ainsi à des densités énergétiques relativement élevées pour des systèmes en physisorption pure. La synthèse du MOF le plus performant de cette série (MIL-160(Al)) a été mise à l’échelle. Ce matériau a ensuite été mis en forme et ses propriétés de stockage de chaleur ont été évaluées dans un prototype de laboratoire (réacteur ouvert).Les applications de stockage inter saisonnier requièrent des matériaux avec une densité énergétique plus élevée par rapport à celle des adsorbants physiques et à ce titre, les composites qui résultent de l’encapsulation de sels inorganiques au sein de matrices poreuses sont intéressants en termes de densité énergétique et de stabilité chimique. De ce fait, le deuxième chapitre porte sur l’exploration d’une série de MOFs en tant que matrices d’encapsulation de sels afin de préparer des composites pour le stockage de l’énergie.Les MOFs sélectionnés permettent d’étudier l’influence de certains paramètres de la matrice (balance amphiphile, volume/taille des pores) sur les propriétés d’adsorption d’eau des composites. Les capacités de stockage énergétique des composites ont été évaluées dans les conditions d’utilisation d’un système de stockage d’énergie.Finalement la capacité de stockage élevée et la bonne stabilité de cyclage (adsorption-désorption) des deux meilleurs composites à base de matrices mésoporeuses (MIL-100(Fe) et MIL-101(Cr)) confirment l’intérêt de ces solides pour ce type d’application<br>Nowadays the forceful development of the energy storage technologies requires the design of novel adsorbents. Energy reallocation concept allows storing renewable solar energies at short (hours) and long term (inter seasonal) using adsorption method. Energy storage materials can be divided in chemical storage materials, physical storage materials and composite materials (inorganic salt in porous matrix).Metal-Organic Frameworks (MOFs) are a new class of porous crystalline materials that are built from an inorganic subunits and organic ligands defining an ordered structure with regular accessible porosity. In comparison with other classes of porous solids, MOFs display a higher degree of versatility (chemical composition, topology) and tunable amphiphilic character, pore volume, pore size, shape, etc.In this work, we have studied a series of water stable porous metal carboxylates made from cheap metal cations (Fe3+, Al3+, Cr3+, Ti4+, Zr4+) and polycarboxylate linkers as pure physical adsorbents and as host matrices of salts for the design of composite adsorbents. The study of the adsorption properties of pure MOFs in conditions of thermal energy storage system has shown high water adsorption capacity and high energy storage densities.The most promising MOF from this series namely MIL-160(Al) has been prepared at large scale, processed as pellets and then evaluated in open-reactor prototype.The second chapter has been focused on the first exploitation of a series of Metal Organic Framework (MOFs) as host matrices of salts for the preparation of composite sorbents for heat storage application.Indeed, inter seasonal energy storage requires materials with higher energy densities (composite and chemical storage materials), than physical sorption materials can offer. We have selected a series of MOFs differing by their amphiphilic balance and pore volume in order to investigate the impact of such physico-chemical properties on the water sorption properties of composites. The energy storage capacity of salt-MOFs composites has been evaluated in representative conditions of thermal storage devices. The high energy storage capacity and good stability under numerous adsorption-desorption cycles for two composites based on mesoporous MIL-100(Fe) and MIL-101(Cr) confirm the potentiality of such composites for this application
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