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1
Tucić, Aleksandar. "Wet chemical synthesis and characterization of organic/TiO 2 multilayers." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-34138.
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Kasumba, John. "Organic Chemical Characterization Of Primary And Secondary Biodiesel Exhaust Particulate Matter." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/358.
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Biodiesel use and production has significantly increased in the United States and in other parts of the world in the past decade. This change is driven by energy security and global climate legislation mandating reductions in the use of petroleum-based diesel. Recent air quality research has shown that emission of some pollutants such as CO, particulate matter (PM), SO2, hydrocarbons, and carcinogenic polycyclic aromatic hydrocarbons (PAHs) is greatly reduced with biodiesel. However, studies have also shown that some unregulated emissions, such as gas-phase carbonyls, are increased with biodiesel combustion. Very limited research has been done to investigate the particle-phase carbonyl and quinone emissions from biodiesel combustion. Also, very limited studies have investigated the ozone oxidation of biodiesel exhaust PM. Fatty acid methyl esters (FAMEs) are found in high abundance in biodiesel exhaust PM. The presence of these FAMEs in biodiesel exhaust PM can potentially alter the kinetics of the reactions between ozone and particle-phase PAHs.
In this study, an Armfield CM-12 automotive light-duty diesel engine operated on a transient drive cycle was used to generate PM from various waste vegetable oil (WVO) and soybean biodiesel blends (containing 0%, (B00), 10% (B10), 20% (B20), 50% (B50), and 100% (B100) biodiesel by volume). The primary PM emissions were sampled using Teflon-coated fiberfilm filters. Laboratory PAHs, FAMEs, and B20 exhaust PM were exposed to ~0.4 ppm ozone for time periods ranging from 0-24 hours in order to study the effect of FAMEs and biodiesel exhaust PM on the ozonolysis of PAHs. Organic chemical analysis of samples was performed using gas chromatography/mass spectrometry (GC/MS). PAHs, carbonyls, FAMEs, and n-alkanes were quantified in the exhaust PM of petrodiesel, WVO and soybean fuel blends. The emission rates of the total PAHs in B10, B20, B50, and B100 exhaust PM decreased by 0.006-0.071 ng/µg (5-51%) compared to B00, while the emission rates for the FAMEs increased with increasing biodiesel content in the fuel. The emission rates of the total n-alkanes in B10, B20, B50, and B100 exhaust PM decreased by 0.5-21.3 ng/µg (4-86%) compared to B00 exhaust PM. The total emission rates of the aliphatic aldehydes in biodiesel exhaust PM (B10, B20, B50, and B100) increased by 0.019-2.485 ng/µg (36-4800%) compared to petrodiesel. The emission rates of the total aromatic aldehydes, total aromatic ketones, and total quinones all generally decreased with increasing biodiesel content in the fuel.
With the exception of benzo[a]pyrene, the pseudo-first order ozone reaction rate constants of all the PAHs decreased by 1.2-8 times in the presence of the FAMEs. Phenanthrene, fluoranthene, and pyrene were the only PAHs detected in the B20 exhaust PM, and their ozone reaction rate constants were about 4 times lower than those obtained when the PAHs alone were exposed to ozone.
The findings of this study indicate that there are both positive and negative effects to emissions associated with biodiesel use in light-duty diesel engines operating on transient drive cycle.
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Parshad, Henrik. "Design of poorly soluble drug salts : pharmaceutical chemical characterization of organic salts /." [Cph.] : Department of Pharmaceutics, The Danish University of Pharmaceutical Sciences, 2003. http://www.dfh.dk/phd/defences/henrikparshad.htm.
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Finessi, Emanuela <1977>. "Chemical characterization of atmospheric secondary organic aerosol of biogenic and anthropogenic origin." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2808/.
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The main objective of this thesis was the chemical characterization of synthetic secondary organic aerosol (SOA) produced from atmospherically relevant anthropogenic and biogenic VOCs during reaction chamber experiments. In parallel, the resulting chemical features of these laboratory-SOA were used to interpret the composition of ambient samples of atmospheric fine particulate matter collected at several sites in Europe, in order to determine the fraction of ambient aerosol organic mass accounted for by biogenic and anthropogenic SOA.
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Governal, Robert Andrew. "Characterization and removal of organic contaminants in ultrapure water systems." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185875.
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Ultrapure water is becoming increasingly important to the semiconductor, pharmaceutical and power industries. Stricter industrial requirements concerning water purity can be realized from pilot scale research. Such a system was designed and operated to determine improved methods to characterize and remove organic contaminants in industrial scale ultrapure water systems. Theoretical modelling of the polishing loop was performed for variable order kinetics; intrinsic reaction parameters were developed, and are potentially scaleable to larger systems. Application of the population balance to the actions of process components on organic particle distributions generated novel oxidation and fragmentation parameters that are scaleable to larger systems. Optimization of bacterial growth media resulted in the increased detection of viable bacterial concentrations. A significant fraction of TOC in the polishing loop was found to exist as assimilable organic carbon; the action of process components, thought to remove contaminants, can generate bacteria nutrients from more complex organics. The situating of a polymeric filter before a UV unit resulted in increased removal of organic contaminants; reversing the sequence enhanced the removal of low molecular weight and low charge to mass ratio compounds. The combination of UV-185 and dissolved ozone resulted in synergistic removal of organic contaminants from ultrapure water. The invention of a novel catalytic filter designed to physically separate and then oxidize contaminants resulted in enhanced removal of organics from ultrapure water. A study of viruses in ultrapure water showed that UV-185 and ozone effectively removed viruses, yet ion exchange gave only two orders of magnitude removal in viable counts. This research may be used to augment present systems and/or design new systems. Continued research along the lines specified in this document will generate further understanding of ultrapure water and ultrapure water systems.
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Tucić, Aleksandar [Verfasser]. "Wet chemical synthesis and characterization of organic, TiO2 multilayers / vorgelegt von Aleksandar Tucić." Stuttgart : Max-Planck-Inst. für Metallforschung, 2008. http://d-nb.info/995389497/34.
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Hunt, James. "Chemical Characterization of Dissolved Organic Matter: Competitive Effects on Phosphorus Sorption to Minerals." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/HuntJ2006.pdf.
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Sundberg, Henrik. "Toxicological and Chemical Characterization of Organic Pollutants with Potential to Adversely Affect Fish." Doctoral thesis, Stockholm : Department of Applied Environmental Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-510.
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Malloy, Quentin Gerald James. "Chemical and physical characterization of secondary organic aerosol formation from select agricultural emissions." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=33&did=1871857121&SrchMode=1&sid=2&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270140114&clientId=48051.
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Sullivan, Amy Patricia. "The Ambient Organic Aerosol Soluble in Water: Measurements, Chemical Characterization, and an Investigation of Sources." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-05022006-111928/.
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Thesis (Ph. D.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2007.Rodney J. Weber, Committee Chair ; Michael H. Bergin, Committee Member ; Committee Member ; Martial Taillefert, Committee Member ; Paul H. Wine, Committee Member.
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Siczka, John Stephen. "The characterization of dissolved organic material in natural waters and the phase-change behavior of organic matter during chemical coagulation." Thesis, This resource online, 1997. http://scholar.lib.vt.edu/theses/available/etd-08252008-162755/.
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Wang, Kai [Verfasser]. "Chemical characterization of organic aerosol from Chinese cities using high resolution mass spectrometry / Kai Wang." Mainz : Universitätsbibliothek Mainz, 2019. http://d-nb.info/1201829089/34.
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Minutillo, Nicholas G. "The Growth and Characterization of Gallium Arsenide Nanowire Structures by Metal Organic Chemical Vapor Deposition." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1416593665.
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Shan, Jingning. "Synthesis of organic and inorganic compounds for OLED application: Physico-chemical characterization of new diamines, heterocycles and group 13 compounds." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/29163.
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This thesis is focused on the synthesis and characterization of organic and inorganic electroluminescent materials for organic light-emitting diodes (OLED). The synthetic work was aimed at several of the key components of multilayer OLEDs and followed the latest developments in this area. Three types of OLED materials, namely hole-transport (HT), electron-transport (ET) and emission (EM) materials in four groups were successfully synthesized. The characterization of these materials focuses on the physical and chemical features that are important in defining performance parameters. This chemist's perspective highlights the potential application of these novel compounds employed in fabricating OLEDs, which is based on the results from thermal, photophysical and electrochemical analysis.
Chapter one outlines the background of OLED, the operation of a double-layer and multilayer OLEDs and the current state of OLED materials. The objectives of this thesis are proposed after describing the general techniques that are important for characterization of the parameters needed for further OLED fabrication.
Chapter two focuses on the synthesis and characterization of HT materials based of aryldiamines with a naphthalene core (bis(N;N-diaryl)-1,5-diaminonaphthalene). Pd-based catalysts have been employed in the C-N bond formation steps of the synthesis of these compounds. The thermal results indicated that these diamines, particularly when they possess bulky aryl groups such as biphenyl and naphthyl, had high glass transition temperatures and thus offer the potential for improving upon OLED stability.
Chapter three is concerned with developing C-4 substituted tris(8-hydroxyquinoline) aluminum (Alq3) derivatives. Alq3 is frequently used as both an ET and an EM material in OLEDs. The modification of the C-4 position of Alq3 and the subsequent influence on the LUMO energy was investigated.
In Chapter four, we investigated EM materials by preparing and characterizing substituted salicylaldimine diphenylboron complexes. Thermal characterization of these compounds indicated that a bulky substituent was needed to improve the thermal stability of these boron complexes.
Chapter five reports our effort to synthesize a novel ET material that was designed as a perimidine-based analogue of 2,2 ',2″-(Benzene-1,3,5-triyl)-tris(1-phenyl-1H-benzimidazole) (TPBI).
In Chapter six, a broad summary of these efforts and future prospects are presented. (Abstract shortened by UMI.)
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Mostovaya, Alina. "Dissolved organic matter in lakes : Chemical diversity and continuum of reactivity." Doctoral thesis, Uppsala universitet, Limnologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316893.
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Dissolved organic matter (DOM) is the largest pool of organic carbon in aquatic systems and an important component of the global carbon cycle. Large amounts of DOM are decomposed within lakes, resulting in fluxes of CO2 and CH4 to the atmosphere. Therefore, there is a considerable interest in understanding the controls of DOM decomposition in freshwaters. There is evidence that in lakes intrinsic controls related to DOM composition are of primary importance, yet our knowledge about molecular drivers of DOM degradation is limited. This thesis addresses the link between chemical composition and reactivity of lake DOM by applying an experimental approach, molecular-level DOM characterization, and kinetic modeling of DOM decay. The first study shows that photoinduced transformations and partial removal of colored aromatic components of DOM have profound effects on DOM degradation kinetics, mediated by the shifts in the relative share of rapidly and slowly degrading DOM fractions. Two following studies estimate exponential decay coefficients for each individual molecular formula identified within bulk DOM. A continuous distribution of exponential decay coefficients is found within bulk DOM, which directly corroborates the central and previously empirically untested assumption behind the reactivity continuum model of DOM decay. Further, individual decay rates are evaluated in connection to specific molecular properties. On average, highly unsaturated and phenolic compounds appear to be more persistent than compounds with higher aromatic content (plant polyphenols and polycondensed aromatics), and aliphatic compounds demonstrate the highest decay rates. The reactivity of aromatics additionally increases with increasing nominal oxidation state of carbon. Molecular analysis further indicates that increasing reactivity of DOM after UV exposure is caused by disintegration of supramolecular complexes. Study IV shows that changes in relative proportion of terrestrial versus algal DOM control degradability of DOM through seasons. Under ice, when algal-derived DOM is maximally depleted, DOM degradation potential converges to similarly low levels, regardless of lake type (productive or humic), and bacterial respiration primarily relies on terrestrial carbon. This suggests a general pattern of baseline metabolism across boreal lakes. I conclude that DOM is a dynamic reactivity continuum and a tight link exists between DOM behavior and compositional properties.
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Carlegrim, Elin. "Preparation and characterization of an organic-based magnet." Licentiate thesis, Norrköping : Department of Science and Technology, Linköping University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10426.
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Holavanhalli, Jayatirtha. "Growth and characterization of ZnSe on GaAs and Si substrates using organic chemical vapour deposition technique." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55608.
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Quan, Tracy M. (Tracy Michelle) 1977. "Chemical characterization of dissolved organic matter (DOM) in seawater : structure, cycling, and the role of biology." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/39806.
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Thesis (Ph. D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and, the Woods Hole Oceanographic Institution), 2005.Includes bibliographical references.
The goal of this thesis is to investigate three different areas relating to the characterization of dissolved organic matter (DOM): further determination of the chemical compounds present in high molecular weight DOM (HMWDOM), the cycling of individual compounds within the HMWDOM pool, and the biological controls on DOM release. The first section of this thesis provided additional molecular level characterization of HMWDOM. While some individual components have been identified, the total yield of compounds isolated is much smaller than the amount expected by spectroscopic analysis by nuclear magnetic resonance (NMR) spectroscopy. Since the majority of the as-yet unidentified carbon was inferred to be carbohydrate, periodate over-oxidation was used to analyze this fraction. Analysis of both surface and deep water HMWDOM samples indicated that the majority of the carbon present was periodate over-oxidizable, including 70% of the aliphatic NMR signal. Comparison of the periodate demand for HMWDOM versus that for linear glucopolysaccharide standards indicated that HMWDOM had a greater degree of branching. Based on the changes in the H NMR spectra during the reaction, it was concluded that 6-deoxysugars were the primary compounds in the unidentified fraction of HMWDOM. Compound specific radiocarbon analysis can provide information about the cycling and relative ages for individual HMWDOM components. In the second section of this thesis, a new method was presented for the purification of individual underivatized amino acids hydrolyzed from HMWDOM.
(cont.) This new separation protocol utilized various chromatographic techniques, including cation exchange chromatography and high- pressure liquid chromatography (HPLC) using C18 and strong cation exchange (SCX) columns. Six amino acids were isolated from a HMWDOM sample with sufficient purity and quantity for radiocarbon analysis. These amino acids had a range of A'4C values, from 121%o to -454%o. The final section investigates biological controls on the dissolved organic nitrogen (DON) pool. Total hydrolyzable amino acids (THAA), and nucleic acids were measured for four incubations: a control incubation, a grazer added incubation, a zero virus incubation, and a 10 times virus incubation. Comparison to the control showed THAA and nucleic acid release were influenced by viruses but not grazers.
by Tracy M. Quan.
Ph.D.
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Lienerth, Peter. "Elaboration and characterization of field-effect transistors based on organic molecular wires for chemical sensing applications." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAD003/document.
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Il est reconnu que la structure des semi-conducteurs organiques influence la sensibilité et la sensitivité des capteurs des gaz. Pour améliorer la compréhension des mécanismes sous-jacents dans les capteurs à base des transistors d’effet de champ organique (OFETs) cette thèse a exploré trois pistes différentes : L’utilisation de l’hystérésis des caractéristiques de transfert comme paramètre de détection des gaz est étudié. En ajoutant l’hystérésis aux paramètres standards, on améliore la sélectivité des OFETs à base de poly(3-hexylthiophène) aux gaz polaires. Des mesures transitoires de courant indiquent que la cinétique de piégeage et de piégeage des porteurs de charges est à l’origine de cette amélioration. Pour comprendre l’influence qu’à la structure moléculaire sur la sensibilité aux vapeurs d’éthanol, des polymères avec des chaînes latérales alcoxyle dont on fait varier la polarité ainsi que l’encombrement stérique, ont été étudiés. L’intensité de la réponse est corrélée avec la quantité d’analyte absorbée et le moment dipolaire des chaînes latérales. Pour permettre l’étude des mécanismes à l’échelle nanométrique, une partie de ce travail se concentre sur la fabrication de transistors avec une taille de canal réduite. En utilisant le nitrure de silicium comme couche diélectrique, on réduite les tensions de commande et les propriétés chimiques à l’interfaceThe molecular structure of organic semiconductors which can be tailored by the chemical synthesis influences the sensitivity and selectivity of gas sensor devices. To improve the understanding of the ongoing mechanisms in sensors based on organic field effect transistors (OFETs) this thesis follows three different tracks: The applicability of the hysteresis of the transfer characteristics as a gas sensing parameter is studied. As a complement to the standard transistor parameters the hysteresis improves the selectivity of poly(3-hexylthiophen-2,5-diyl) based OFETs to polar gases. Transient current measurements indicate the additional dependence on the detrapping kinetics as origin of the increased selectivity. To understand the influence of the molecular structure on the gas sensing behavior, polymers with alkoxy side chains, varying in polarity and steric hindrance, are used as gas sensing layer for ethanol vapor. The response strength correlates with the amount of absorbed analyte and the dipole moment of the side chains. To enable investigations of the mechanisms at the nanoscale, one part of this work focuses on the preparation of transistors with a reduced channel length. By using silicon nitride as dielectric layer, driving voltages decreased and interface properties could be improved
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Huzyak, Paige M. "Synthesis and Characterization of Organic-Inorganic Hybrid Materials for Thermoelectric Devices." TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1600.
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The development of organic-inorganic hybrid materials is of great interest in thermoelectrics for its potential to combine the desirable characteristics of both classes of materials. Thermoelectric materials must combine low thermal conductivity with high electrical conductivity, but in most materials, thermal and electrical conductivity are closely related and positively correlated. By combining the low thermal conductivity, flexibility, facile processing, and low cost of organic components with the high electrical conductivity and stability of inorganic components, materials with beneficial thermoelectric properties may be realized.
Here, we describe the synthesis and characterization of anthracene-containing organic-inorganic hybrid materials for thermoelectric purposes. Specifically, POSS-ANT was synthesized when aminopropylisobutyl-POSS was functionalized with a single anthracene unit via DCC-mediated amide formation. Acrylate-POSS was functionalized with multiple anthracene units in a Heck coupling reaction to synthesize System 1. System 2 was developed through a two-step synthetic process. In the first reaction, (3- acryloxypropyl)methyl dimethyoxy silane was functionalized with anthracene at the 9- position through a Heck coupling reaction. The second reaction was a base-catalyzed solgel process to form polymeric nanoparticles. Finally, System 3 was synthesized through a similar process to System 2, though polymers formed in the initial step. The System 3 precursor was to be developed through a potassium carbonate-catalyzed ether synthesis
from 3-(bromopropyl)trimethoxysilane and 9-anthracene methanol, followed by a basecatalyzed sol-gel process to form nanoparticles. The precursor was never isolated because of premature polymerization during the precursor synthesis step, and polymeric nanoparticles were obtained for System 3 during the sol-gel process. These materials were characterized by TEM to reveal the nanostructures that formed upon evaporation from solution. Future work will focus on the characterization of thermoelectric parameters and incorporation into thermoelectric devices.
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Gao, Min. "CHEMICAL CHARACTERIZATION OF SOIL ORGANIC MATTER IN AN OLIGOTROPHIC, SUBTROPICAL, FRESHWATER WETLAND SYSTEM: SOURCES, DIAGENESIS AND PRESERVATION." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/3625.
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Freshwater wetland soils of the Everglades were studied in order to assess present environmental conditions and paleo-environmental changes using organic geochemistry techniques. Organic matter in dominant vegetation, peat and marl soils was characterized by geochemical means. Samples were selected along nutrient and hydrology gradients with the objective to determine the historical sources of organic matter as well as the extent of its preservation.
Effective molecular proxies were developed to differentiate the relative input of organic matter from different biological sources to wetland soils. Thus historical vegetation shifts and hydroperiods were reconstructed using those proxies. The data show good correlations with historical water management practices starting at the turn of the century and during the mid 1900’s. Overall, significant shortening of hydroperiods during this period was observed.
The soil organic matter (SOM) preservation was assessed through elemental analysis and molecular characterizations of bulk 13C stable isotopes, solid state 13C NMR spectroscopy, UV-Vis spectroscopy, and tetramethyl ammonium hydroxide (TMAH) thermochemolysis-GC/MS. The relationship of the environmental conditions and degradation status of the soil organic matter (SOM) among the sites suggested that both high nutrient levels and long hydroperiod favor organic matter degradation in the soils. This is probably the result of an increase in the microbial activity in the soils which have higher nutrient levels, while longer hydroperiods may enhance physical/chemical degradation processes. The most significant transformations of biomass litter in this environment are controlled by very early physical/chemical processes and once the OM is incorporated into surface soils, the diagenetic change, even over extended periods of time is comparatively minimal, and SOM is relatively well preserved regardless of hydroperiod or nutrient levels. SOM accumulated in peat soils is more prone to continued degradation than the SOM in the marl soils. The latter is presumably stabilized early on through direct air exposure (oxidation) and thus, it is more refractory to further diagenetic transformations such as humification and aromatization reactions.
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Gao, Min. "Chemical characterization of soil organic matter in an oligotrophic, subtropical, freshwatwer wetland system : sources, diagenesis and preservation." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/3618.
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Freshwater wetland soils of the Everglades were studied in order to assess present environmental conditions and paleo-environmental changes using organic geochemistry techniques. Organic matter in dominant vegetation, peat and marl soils was characterized by geochemical means. Samples were selected along nutrient and hydrology gradients with the objective to determine the historical sources of organic matter as well as the extent of its preservation.
Effective molecular proxies were developed to differentiate the relative input of organic matter from different biological sources to wetland soils. Thus historical vegetation shifts and hydroperiods were reconstructed using those proxies. The data show good correlations with historical water management practices starting at the turn of the century and during the mid 1900’s. Overall, significant shortening of hydroperiods during this period was observed.
The soil organic matter (SOM) preservation was assessed through elemental analysis and molecular characterizations of bulk 13C stable isotopes, solid state 13C NMR spectroscopy, UV-Vis spectroscopy, and tetramethyl ammonium hydroxide (TMAH) thermochemolysis-GC/MS. The relationship of the environmental conditions and degradation status of the soil organic matter (SOM) among the sites suggested that both high nutrient levels and long hydroperiod favor organic matter degradation in the soils. This is probably the result of an increase in the microbial activity in the soils which have higher nutrient levels, while longer hydroperiods may enhance physical/chemical degradation processes. The most significant transformations of biomass litter in this environment are controlled by very early physical/chemical processes and once the OM is incorporated into surface soils, the diagenetic change, even over extended periods of time is comparatively minimal, and SOM is relatively well preserved regardless of hydroperiod or nutrient levels. SOM accumulated in peat soils is more prone to continued degradation than the SOM in the marl soils. The latter is presumably stabilized early on through direct air exposure (oxidation) and thus, it is more refractory to further diagenetic transformations such as humification and aromatization reactions.
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Shelton, Bryan Stephen. "The simulation, processing, and characterization of AlGaN/GaN heterojunction transistors grown by metalorganic chemical vapor deposition /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004376.
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Sridhar, Manasa. "Template Directed Synthesis and Characterization of Organic Mesoporous Polymers and their Adsorption Performance for Lysozyme." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1337717290.
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Rigali, Mark Joseph 1963. "Chemical characterization of solid graphitic carbonaceous matter associated with the Oklo natural fission reactors and uranium ore deposits, Gabon (West Africa)." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/288812.
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Solid graphitic carbonaceous matter (CM) is closely associated with the Oklo uranium ore deposits and several of the natural fission reactors in Gabon, West Africa. This material facilitated the containment of uranium and numerous fissiogenic isotopes in these natural reactors for a period of nearly 2 Ga. Hence it is the subject of detailed studies because it may be useful as an analogue for carbonaceous materials, e.g. technical bitumens, that are currently being considered for the encapsulation and storage of anthropogenic radioactive waste. Chemical and structural analyses of the uraniferous CM associated with the natural fission reactors indicate that it is a polymer-like solid composed mainly of polycyclic aromatic hydrocarbons (PAHs) that are randomly oriented (turbostratic) and vary in size from several to several tens of A. Short-chained aliphatic hydrocarbons and oxygen-bearing moieties are attached to the PAH sheets and frequently bridge adjacent sheets. The Oklo uraniferous CM exhibits very high free radical concentrations, which can exceed 1021 free radicals/g organic carbon. The organic free radicals are stable PAH moieties located at or very near the surfaces of these organic solids, mainly on the internal surfaces of pores. Despite their presence, these pores could not have served as effective conduits for the transport of radionuclides by aqueous solutions through and out of the CM matrix. This is because of the very small average size of the pores, together with the CM's non-wettability by aqueous solutions. The Oklo CM has endured oxidation-reduction reactions during uranium mineralization, exposure to ionizing radiation, and alteration associated with the radiolysis products of water during and after natural reactor operation, perhaps up until the present time. Still, the CM acted as an effective barrier to radionuclide migration out of the CM-rich natural fission reactors. Properties, including its aromatic composition, resistance to alteration by ionizing radiation, and its non-wettability to aqueous solutions, make the Oklo uraniferous CM an effective barrier to radionuclide migration. These properties should be incorporated into man-made carbonaceous materials currently being considered for use in the storage of radioactive waste.
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Webb, Lauren J. Gray Harry B. "Chemical characterization and charge carrier dynamics of crystalline silicon(111) surfaces modified with surface-bound organic functional groups /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-05262005-123044.
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Loh, Ai Ning. "Chemical, isotopic and microbial characterization of dissolved and particulate organic matter in estuarine, coastal and open ocean systems." W&M ScholarWorks, 2002. https://scholarworks.wm.edu/etd/1539791565.
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Dissolved and suspended particulate organic carbon (DOC, POC), nitrogen (DON, PON), phosphorus (DOP, POP) and inorganic nutrient distributions and elemental ratios were measured and evaluated for the Atlantic, Southern, and Pacific Oceans. Results indicate that DOC is remineralized during mean deep-water transport from the North Atlantic to the North Pacific. Elemental ratios for both dissolved organic matter (DOM) and particulate organic matter (POM) indicate that organic N is preferentially remineralized compared with organic C, while organic P is preferentialy remineralized relative to both organic C and N. Comparison between the DOM and POM pools further suggests that surface POM may be less refractory than concurrently sampled DOM. Major compound class compositions of ultrafiltered DOM (UDOM) in the North Atlantic, North Pacific and Chesapeake Bay indicate that the majority of UDOM was comprised mainly of a molecularly-uncharacterized fraction, followed by carbohydrates, proteins and lipids. Delta14C and delta 13C results of UDOM compound classes suggest that UDOM in Bay mouth and surface open ocean waters were similarly dominated by old, marine sources, while UDOM from the freshwater endmember was influenced by much younger terrestrial sources. Results indicate that DOM is comprised of different aged organic fractions and provide evidence for a potential organic "size"-age continuum; from low-molecular weight DOM (oldest) to UDOM (intermediate age) to POM (youngest). Lipid biomarker results indicate that North Atlantic and Pacific UDOM and POM were relatively more reactive at the surface compared with greater depths, coinciding with elemental C:P and N:P ratios greater than Redfield. Factor analyses suggest that there exists a "lability continuum" spanning from surface ocean POM to riverine and deep ocean UDOM. Terrigenous organic material was found at all Bay sites although autochthonous sources of organic matter were also important. Dark microbial incubations of DOM from the Pacific Subtropical Front and South Atlantic Bight indicate that open ocean DOM is relatively refractory over short time scales (less than 2 months). Experiments with plankton leachate DOM show that this sub-pool of DOM is relatively labile and is converted to refractory DOM within days. DOP is preferentially remineralized in all experiments compared with DOC or DON.
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Al, Tahtamouni Talal Mohammed Ahmad. "MOCVD growth and characterization of al-rich ALN/ALGAN epilayers and quantum wells." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/431.
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Müller, Nils. "Characterization of dangerous pollutants in bio and waste ashes : Analysing content and leaching behaviour of several ashes for persistent organic pollutants and toxic heavy metals." Thesis, Umeå universitet, Kemiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-138124.
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Lambert, Damien Jean Henri. "Growth and characterization of group III-nitride power transistors, power rectifiers and solar-blind detectors by metalorganic chemical vapor deposition /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004311.
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Tadanier, Christopher J. "Influence of Operational Characterization Methods on DOM Physicochemical Properties and Reactivity with Aqueous Chlorine." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/40503.
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The physicochemical properties and chemical reactivity of dissolved organic matter (DOM) are of tremendous practical significance in both natural and engineered aquatic and terrestrial systems. DOM is frequently extracted, fractionated, and concentrated from environmental samples using a variety of operationally defined physical and chemical processes in order to facilitate study of specific physicochemical properties and aspects of its chemical reactivity. This study was conducted to systematically examine the influence of operationally defined physical and chemical characterization methods on observed DOM physicochemical properties and reactivity with aqueous chlorine. The effects of chemical separation were evaluated by applying an existing resin adsorption based procedure which simultaneously extracts and fractionates DOM and inorganic constituents into hydrophobic and hydrophilic acid, base, and neutral dissolved material matrix (DMM) fractions. Physical separation based on DOM apparent molecular weight (AMW) was also evaluated using batch ultrafiltration (UF) data in conjunction with a suitable membrane permeation model. Linear independence of membrane solute transport was theoretically described using non-equilibrium thermodynamics and experimentally demonstrated for AMICON® YC/YM series UF membranes. Mass balances on DMM fraction constituents in untreated and previously coagulated natural waters indicated that quantitative recovery (100 ± 2%) of DOM constituents was achieved, while recovery of inorganic constituents such as iron and aluminum was substantially incomplete (30%-74%). Comparison of whole-water DOM properties with those mathematically reconstituted from DMM fractions demonstrated a marked shift in DOM properties toward lower AMW. Evidence of pH induced partial hydrolysis of protein, polysaccharide, and ester DOM components was also observed. Decreased specific Cl2 demand (mmol DCl2/ mmol DOM) and specific trihalomethane formation (mmol THM/mmol DOM) following chemical fractionation were attributed to increased molar DOM concentration and decreased DOM association with colloidal iron oxide surfaces. Collectively, the results of this research indicate that operational characterization methods result in alteration of DOM physicochemical properties and reactivity with aqueous chlorine, and caution is therefore advisable when interpreting the results of studies conducted using chemically extracted or fractionated DOM.Ph. D.
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Scott, Joseph Brian. "Synthesis and Characterization of Some Rhenium Complexes." TopSCHOLAR®, 2009. http://digitalcommons.wku.edu/theses/114.
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Plastics or polymers are thought to behave oppositely from metals. Ideally, polymers behave as insulators while metals conduct electricity. Shirakawa and coworkers discovered conductive polymers in 1977.1 These conductor polymers have been extensively studied, discovering that charge transfer oxidative doping of polyacteylene could increase its conductivity by 12 orders of magnitude. Polyacetylene, although showing promise as an organic conductor, because it is highly air-sensitive and oxidizes when exposed to molecular oxygen, therefore making this an unattractive use for commercial products. Attention has been focused on heterocylic aromatic polymers such as polythiophene and polypyrrole, in efforts to produce conductive polymers that are air-stable, tractable, and have a low band gap. The lone-pair electrons of the sulfur and nitrogen atoms tend to stabilize the positive charges of the p-doped polymers through resonance. 2
By using Shirakawas’ idea of using polypyrrole as the focus point of our research and expanding upon that by the addition of a rhenium metal to an organic compound, (1,2-C5H3(CNR)2) and this should offer some new and interesting chemical properties. These new properties are; new optical properties, new electronic properties, improved physical properties, and a reversible electrochemical shift. This research will help in the field of organometallic semiconductors in applications such as OLED’s, and electrochromic windows.3-6
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Beltz, Katylynn. "The Development of Calibrants through Characterization of Volatile Organic Compounds from Peroxide Based Explosives and a Non-target Chemical Calibration Compound." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/817.
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Detection canines represent the fastest and most versatile means of illicit material detection. This research endeavor in its most simplistic form is the improvement of detection canines through training, training aids, and calibration. This study focuses on developing a universal calibration compound for which all detection canines, regardless of detection substance, can be tested daily to ensure that they are working with acceptable parameters. Surrogate continuation aids (SCAs) were developed for peroxide based explosives along with the validation of the SCAs already developed within the International Forensic Research Institute (IFRI) prototype surrogate explosives kit. Storage parameters of the SCAs were evaluated to give recommendations to the detection canine community on the best possible training aid storage solution that minimizes the likelihood of contamination. Two commonly used and accepted detection canine imprinting methods were also evaluated for the speed in which the canine is trained and their reliability.
As a result of the completion of this study, SCAs have been developed for explosive detection canine use covering: peroxide based explosives, TNT based explosives, nitroglycerin based explosives, tagged explosives, plasticized explosives, and smokeless powders. Through the use of these surrogate continuation aids a more uniform and reliable system of training can be implemented in the field than is currently used today. By examining the storage parameters of the SCAs, an ideal storage system has been developed using three levels of containment for the reduction of possible contamination. The developed calibration compound will ease the growing concerns over the legality and reliability of detection canine use by detailing the daily working parameters of the canine, allowing for Daubert rules of evidence admissibility to be applied. Through canine field testing, it has been shown that the IFRI SCAs outperform other commercially available training aids on the market. Additionally, of the imprinting methods tested, no difference was found in the speed in which the canines are trained or their reliability to detect illicit materials. Therefore, if the recommendations discovered in this study are followed, the detection canine community will greatly benefit through the use of scientifically validated training techniques and training aids.
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Williamson, Rhett J. "Qualitative Analysis for the Characterization and Discrimination of Printing Inks." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3055.
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Improvements in printing technology and the wide accessibility of advanced printers has resulted in an increase in counterfeiting. Of particular interest to forensic document examiners, ink analysis of security documents has emerged as an important tool for the analysis, comparison, and association of inks to a potential production source. In this study, methods were developed for Py-GC/MS, ATR-FTIR, DART-MS, and MALDI-MS analyses of printing inks of four classes: 78 inkjet inks, 76 toners, 79 offset inks, and 86 intaglio inks in order to generate information on the organic chemical characterization of the inks to determine the ability to associate and discriminate the inks for uses in security document examinations. The suite of analytical techniques evaluated in the study focused on having the following analytical characteristics: 1) rapid analysis time, 2) little-to-no sample preparation, 3) minimal destructiveness to the sample, 4) allow for association of inks with the same source of origin as well as discrimination of inks originating from different sources. As a result of this study, a novel searchable library database of inks was developed for use with each analytical chemical method that allows for data fusion.
Py-GC/MS analysis was used to achieve >63% discrimination of toner inks on the basis of the characterization of polymer degradation products. The combination of a protocol implementing first ATR-FTIR and subsequently DART-MS analysis resulted in >96% discrimination for toners, 95% for inkjet, >92% for offset, and >54% for intaglio. In addition, a case study was performed using DART-MS to illustrate its utility as a tool for ink analysis in document examination. The results of MALDI-MS analyses from two different instruments resulted in >90% discrimination of a subset of all inks by characterizing the colorant molecules present in ink formulations. A study characterizing luminescent compounds present in the formulation of inks in crossed-line intersections was performed using a combination of MALDI-MS, LC-MS, and TLC. Overall, it was shown that the combination of analytical techniques included within this dissertation can provide information on the organic chemical composition of four classes of printing inks, which is useful for the future of document examination.
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Janechek, Nathan Joseph. "Atmospheric modeling and experimental characterization of gas and aerosol phase cyclic volatile methyl siloxanes." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6438.
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Cyclic volatile methyl siloxanes (cVMS) are anthropogenic chemicals present in a range of consumer personal care products such as antiperspirants and lotions. They are highly volatile, and readily released to the atmosphere by personal care product use. Generally unreactive, they are found in high concentrations in indoor environments, and transported long distances in the atmosphere. A major removal pathway for these silicon-containing gases is reaction with the OH radical, which has been recently shown to yield secondary Si-containing aerosol compounds in addition to the gas phase products. Despite the significance of the atmospheric fate of these compounds, much of the previous work has focused on the aquatic fate, and almost exclusively on the parent compounds. The oxidation products and potential aerosol species have received much less attention, with almost no ambient measurements or experimental physical property data. This work investigates cVMS with a focus on providing much needed information on potential loadings of the oxidation products, their distribution, and particle phase properties using an atmospheric model and laboratory experiments. Specifically, cVMS was added to the Community Multiscale Air Quality (CMAQ) model; expected concentrations, spatial distribution, and seasonal trends were quantified; cVMS secondary aerosols generated and physical properties characterized; and secondary aerosol parameters for atmospheric modeling developed.
The CMAQ model code was modified to update the chemical mechanism with cVMS, develop emissions, boundary, and deposition parameters to simulate four separate seasons at a spatial resolution of 36 km over North America. Typical model concentrations showed parent compounds were highly dependent on population density as cities had monthly averaged peak decamethylcyclopentasiloxane (D5) concentrations up to 432 ng m−3. Peak oxidized D5 concentrations were significantly less, up to 9 ng m−3, and were located downwind of major urban areas. Model results were compared to available measurements and previous simulation results. Parent compound concentrations in urban locations were sensitive to transport factors, while parent compounds in rural areas and oxidized product concentrations were influenced by large-scale seasonal variability in OH.
Secondary aerosols were formed by reacting cVMS gas in an oxidation flow reactor. The particles were characterized for concentration, size, aerosol yield, morphology, energy-dispersive spectroscopy (EDS) individual particle chemical composition, hygroscopicity (cloud condensation nuclei formation potential), and volatility. Aerosol concentrations were 68 – 220 µg m-3 with aerosol mass fractions (i.e. yields) of 0.22-0.50. Aerosol yield was sensitive to chamber OH, indicating an interplay between oxidation conditions and the concentration of lower volatility species. The D5 oxidation products were non-volatile, with only the smallest particles (10 nm) exhibiting more than 4% of diameter decrease upon heating to 190°C temperature. The D5 oxidation aerosols were relatively non-hygroscopic, with average hygroscopicity kappa of ~0.01.
Experimental data was analyzed to develop secondary aerosol parameters for the CMAQ model. Chamber yield data was fit to a two-product Odum volatility model with yield values of 0.14 and 0.82, corresponding to saturation concentrations of 0.95 and 484 µg m-3, respectively. The recommended enthalpy of vaporization is 18 kJ mol-1 based on other modeled secondary organic aerosol. Recommended molecular weights for the D5 low volatility Odum, high volatility Odum, and non-volatile oligomerization species are 588, 373, and 733 g mol-1 corresponding to OH substituted ring-opened, monomer, and dimer species, respectively.
This work provides simulations of expected concentrations, spatial patterns, and seasonal influence of the parent and oxidized cVMS species to extend beyond the few parent cVMS measurements and nonexistent oxidation product measurements. The modeling work serves as an important tool to guide future field measurements especially important for the confirmation of particle phase oxidation products. Extensive aerosol characterization measurements provide much needed physical property data important for future modeling, risk, and exposure studies.
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Li, Yan [Verfasser], Philippe [Akademischer Betreuer] [Gutachter] Schmitt-Kopplin, Boris P. [Gutachter] Koch, and Michael [Gutachter] Rychlik. "Comprehensive Characterization of Dissolved Organic Matter by Using Chemical Fractionation and High Resolution Organic Structural Spectroscopy / Yan Li ; Gutachter: Philippe Schmitt-Kopplin, Boris P. Koch, Michael Rychlik ; Betreuer: Philippe Schmitt-Kopplin." München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/114756566X/34.
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Kaur, Aman Preet. "N-DOPED MULTIWALLED CARBON NANOTUBES: FUNCTIONALIZATION, CHARACTERIZATION AND APPLICATION IN LI ION BATTERIES." UKnowledge, 2013. http://uknowledge.uky.edu/chemistry_etds/18.
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The focus of this dissertation is to utilize chemical functionalization as a probe to investigate the reactivity of N-doped multiwalled carbon nanotubes (N-MWCNTs). The surface of N-MWCNTs, being a set of potentially reactive graphene edges, provides a large number of reactive sites for chemical modification, so considerable changes in chemical and physical properties can be envisaged. We observed that both reduction (dissolving metal reduction/alkylation) and oxidation (H2SO4/HNO3 and H2SO4/KMnO4 mixtures) of N-MWCNTs lead to formation of interesting spiral channels and spiraled carbon nanoribbons. A variety of techniques, including TGA, SEM, TEM, XRD and surface area measurements were used to analyze these new textural changes. We have developed methods to demonstrate that specific chemistry has occurred on these new structures. To this end, we introduced metal-binding ligands that could be used as probes in imaging and spectroscopic techniques including TEM, STEM, EDX, and EELS. A proposal for the underlying structure of N-MWCNTs responsible for the formation of the new textures is presented. We have investigated the performance of our materials as potential negative electrodes for rechargeable lithium ion batteries.
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Hewage, Dilrukshi C. "SPECTROSCOPIC CHARACTERIZATION OF LANTHANUM-MEDIATED HYDROCARBON ACTIVATION." UKnowledge, 2015. http://uknowledge.uky.edu/chemistry_etds/54.
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Lanthanum (La)-promoted hydrocarbon activation reactions were carried out in a laser vaporization metal cluster beam source. Reaction products were identified by time-of-flight mass spectrometry, and the approximate ionization thresholds of La-hydrocarbon complexes were located with photoionization efficiency spectroscopy. The accurate ionization energies and vibrational frequencies of the La complexes were measured using mass analyzed threshold ionization (MATI) spectroscopy. Their molecular structures and electronic states were investigated by combing the MATI spectroscopic measurements with quantum chemical and Franck-Condon factor calculations.
In this dissertation, La-mediated C-H and C-C bond activation reactions were investigated for several small alkynes (acetylene, propyne) and alkenes (propene, 1,3-butadiene, 1-butene). The C-H bond activation was observed for both alkynes and alkenes and the C-C bond activation for alkenes. The metal-hydrocarbon intermediates formed by the C-H or C-C bond cleavage reacted further with one or more parent hydrocarbon molecules to produce larger species by C-C bond coupling reactions. Structural isomers of the intermediates and products were identified within an energy range of several kilocalories per mole. Reaction pathways for the intermediate and product formations were studied by theoretical calculations.
The ground electron configuration of La atom is 4d16s2.Upon the hydrocarbon coordination, La atom is excited to a 4d26s1 configuration to facilitate the formation of two La-C bonds. After the metal-hydrocarbon complex formation, only one electron is left in the 6s orbital of the metal center. Therefore, the most stable electronic state of the La complexes studied in this work is in a doublet spin state. Ionization of the doublet state yields a preferred singlet ion state. Although La is in the formal oxidation state of +2, the ionization energies of the metal-complexes are significantly lower than that of the free atom. This observation suggests that the concept of the formal oxidation state widely used in chemistry textbooks is not useful in predicting the change of the ionization energy of a metal atom upon ligation. Moreover, ionization has a very small effect on the geometry of the hydrocarbon fragment in each complex but significantly reduces the La-C distances as a result of an additional charge interaction.
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Chichetu, Karen. "Characterization, DNA Binding and Cleavage Activities of New Prodigiosin and Tambjamine Analogues and Their Cu²⁺ and Zn²⁺ Complexes." PDXScholar, 2015. http://pdxscholar.library.pdx.edu/open_access_etds/2467.
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Prodigiosins and tambjamines are natural compounds from bacterial and marine sources belonging to a family containing a common 4-methoxy-2,2'-bipyrrole core. These compounds have received a lot of interest due to their promising biological activities. Studies have suggested DNA as a potential therapeutic target for the natural prodigiosin and tambjamine due to their ability to facilitate oxidative DNA cleavage in the presence of Cu2+. Based on this we sought to study the metal binding activity of new prodigiosin and tambjamine analogues. A new prodigiosin analogue was synthesized and complexed with Cu2+. This revealed 1:1 complex formation between the tripyrrole and Cu2+ that was confirmed by mass spectra and NMR spectra analysis. In addition in situ studies also revealed that our new analogues of prodigiosin cannot bind Zn2+ when the methoxy group on ring B is replaced by an alkyl group or when one of the ring nitrogens is methylated.
Our UV-Vis experiments with calf thymus DNA showed that prodigiosins and tambjamines bind DNA mainly through an external mode, suggesting that hydrogen bonding between the pyrrole ring nitrogens and the bases of DNA takes precedence over stacking interactions. For the new Cu2+ complex synthesized however, we observed spectral changes that suggest intercalation into DNA.
DNA cleavage experiments revealed that the prodigiosin-Cu complex is able to convert supercoiled DNA into its linear form. The data from the gel shift assays fit well to a first-order consecutive reaction model. In addition to preformed metal complexes, we showed DNA cleavage by in situ complexation of the ligands in the presence of Cu2+. However, although we showed Zn2+ complex formation with prodigiosin analogues, in situ studies did not show induction of DNA cleavage by Zn2+ complexes under our experimental conditions.
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McDonald, Shannon Scott. "Characterization and optimization of a high surface area-solid phase microextraction sampler for the collection of trace level volatile organic compounds in the field /." Download the thesis in PDF, 2006. http://www.lrc.usuhs.mil/dissertations/pdf/McDonald2006.pdf.
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Laine, Guy C. "CHARACTERIZATION OF AND CONTROLLING MORPHOLOGY OF ULTRA-THIN NANOCOMPOSITES." UKnowledge, 2013. http://uknowledge.uky.edu/cme_etds/23.
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Ultrathin film nanocomposites are becoming increasingly important for specialized performance of commercial coatings. Critical challenges for ultrathin film nanocomposites include their synthesis and characterization as well as their performance properties, including surface roughness, optical properties (haze, refractive index as examples), and mechanical properties. The objective of this work is to control the surface roughness of ultrathin film nanocomposites by changing the average particle size and the particle volume fraction (loading) of monomodal particle size distributions. This work evaluated one-layer and two-layer films for their surface properties. Monodispersed colloidal silica nanoparticles were incorporated into an acrylate-based monomer system as the model system. Ultrathin nanocomposites were prepared with three different size colloidal silica (13, 45, and 120 nm nominal diameters) at three different particle loadings (20, 40, and 50 vol. % inorganic solids). Silica particles were characterized using DLS and TEM. AFM was used to measure the root mean square roughness (Rq), ΔZ, and location-to-location uniformity of one-layer and two-layer nanocomposite coatings. Developing an understanding about the properties affected by the type and amount of particles used in a nanocomposite can be used as a tool with nanocharacterization techniques to quickly modify and synthesize desired ultrathin film coatings.
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Smith, Austin Gregory. "Characterization and Quantification of Early Stages for Organic Coatings Applied on AA2024/AA7075 by Correlating Frequency Domain Approach in Real Time." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399125698.
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Hancock, Matthew Logan. "THE FABRICATION AND CHARACTERIZATION OF METAL OXIDE NANOPARTICLES EMPLOYED IN ENVIRONMENTAL TOXICITY AND POLYMERIC NANOCOMPOSITE APPLICATIONS." UKnowledge, 2019. https://uknowledge.uky.edu/cme_etds/112.
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Ceria (cerium oxide) nanomaterials, or nanoceria, have commercial catalysis and energy storage applications. The cerium atoms on the surface of nanoceria can store or release oxygen, cycling between Ce3+ and Ce4+, and can therefore act as a therapeutic to relieve oxidative stress within living systems. Nanoceria dissolution is present in acidic environments in vivo. In order to accurately define the fate of nanoceria in vivo, nanoceria dissolution or stabilization is observed in vitro using acidic aqueous environments.
Nanoceria stabilization is a known problem even during its synthesis; in fact, a carboxylic acid, citric acid, is used in many synthesis protocols. Citric acid adsorbs onto nanoceria surfaces, capping particle formation and creating stable dispersions with extended shelf lives. Nanoceria was shown to agglomerate in the presence of some carboxylic acids over a time scale of up to 30 weeks, and degraded in others, at pH 4.5 (representing that of phagolysosomes). Sixteen carboxylic acids were tested: citric, glutaric, tricarballylic, α-hydroxybutyric, β-hydroxybutyric, adipic, malic, acetic, pimelic, succinic, lactic, tartronic, isocitric, tartaric, dihydroxymalonic, and glyceric acid. Each acid was introduced as 0.11 M, into pH 4.5 iso-osmotic solutions. Controls such as ammonium nitrate, sodium nitrate, and water were also tested to assess their effects on nanoceria dissolution and stabilization.
To further test stability, nanoceria suspensions were subject to light and dark milieu, simulating plant environments and biological systems, respectively. Light induced nanoceria agglomeration in some, but not all ligands, and is likely to be a result of UV irradiation. Light initiates free radicals generated from the ceria nanoparticles. Some of the ligands completely dissolved the nanoceria when exposed to light. Citric and malic acids form coordination complexes with cerium on the surface of the ceria nanoparticle that can inhibit agglomeration. This approach identifies key functional groups required to prevent nanoceria agglomeration. The impact of each ligand on nanoceria was analyzed and will ultimately describe the fate of nanoceria in vivo.
In addition, simulated biological fluid (SBF) exposure can change nanoceria’s surface properties and biological activity. The citrate-coated nanoceria physicochemical properties such as size, morphology, crystallinity, surface elemental composition, and charge were determined before and after exposure to simulated lung, gastric, and intestinal fluids. SBF exposure resulted in either loss or overcoating of nanoceria’s surface citrate by some of the SBF components, greater nanoceria agglomeration, and small changes in the zeta potential.
Nanocomposites are comprised of a polymer matrix embedded with nanoparticles. These nanoparticles can alter material and optical properties of the polymer. SR-399 (dipentaerythritol pentaacrylate) is a fast cure, low skin irritant monomer that contains five carbon-carbon double bonds (C=C). It is a hard, flexible polymer, and also resistant to abrasion. It can be used as a sealant, binder, coating, and as a paint additive. In this case, metal oxide nanoparticles were added to the monomer prior to polymerization. Titania nanoparticles are known to absorb UV light due to their photocatalytic nature. Titania nanoparticles were chosen due to their high stability, non-toxicity, and are relatively quick, easy, and inexpensive to manufacture. Channels in thin monomer films were created using a ferrofluid manipulated by magnetic fields.
The mechanical properties of a microfluidic device by rapid photopolymerization is dependent on the crosslinking gradient observed throughout the depth of the film. Quantitative information regarding the degree of polymerization of thin film polymers polymerized by free radical polymerization through the application of UV light is crucial to estimate material properties. In general, less cure leads to more flexibility, and more cure leads to brittleness. The objective was to quantify the degree of polymerization to approximate the C=C concentration and directly relate it to the mechanical properties of the polymer. Polymerization of C=C groups was conducted using a photoinitiator and an UV light source from one surface of a thin film of a multifunctional monomer. The C=C fraction in the film was found to vary with film depth and UV light intensity. The extents of conversion and crosslinking estimates were compared to local mechanical moduli and optical properties. A mathematical model linking the mechanical properties to the degree of polymerization, C=C composition, as a function of film depth and light intensity was then developed. For a given amount of light energy, one can predict the hardness and modulus of elasticity. The correlation between the photopolymerization and the mechanical properties can be used to optimize the mechanical properties of thin films within the manufacturing and energy constraints, and should be scalable to other multifunctional monomer systems.
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Lattach, Youssef. "Development and characterization of sensing layers based on molecularly imprinted conducting polymers for the electrochemical and gravimetrical detection of small organic molecules." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2011. http://tel.archives-ouvertes.fr/tel-00699628.
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In the field of chemical and biological sensors, the increased need for better sensitivity, faster response and higher selectivity during an analysis process, requires the development of more and more efficient transducing sensing layers. In this context, and with the aim to detect small non-electroactive molecules, such as atrazine (ATZ), we designed, characterized and developed sensing layers constituted by functionalized Molecularly Imprinted Conducting Polymers (MICP) and we integrated them into electrochemical and gravimetrical sensors. Starting from acetonitrile pre-polymerization media containing ATZ as template molecules in the presence of thiophene-based functional monomers (FM, namely TMA, TAA, EDOT, TMeOH or Th), differently functionalized and structurally different polythiophene-based FM-MICP films were electrosynthesized onto gold substrates and used for ATZ detection. The sensing properties of FM-MICP layers were shown to result from the presence in their backbones of pre-shaped FM-functionalized imprinted cavities which keep the memory of the targets. Nevertheless, non-specific adsorption onto the surface of the sensing layers takes place systematically, which affects the selectivity of the recognition process. Thanks to surface characterization techniques, we highlighted the influence of the thickness and of the structural properties of the layers on the efficiency of the recognition process. Besides, this latter was shown to operate in the bulk of the polymer matrixes thanks to layers porosity. On another hand, electrochemical measurements correlated with semi-empirical calculations demonstrated the influence of the nature of FM on the strength of the ATZ-FM interaction in the pre-polymerization medium, and then on the number of ATZ molecular imprints and on the sensitivity towards ATZ of the FM-MICP layers. We showed that TAA-MICP, which presents a low limit of detection (10-9 mol L-1) and a large dynamic range (10-8 to 10-4 mol L-1), is the best sensing layer since it offers the best compromise between high level of specific detection of ATZ and low level of non-specific adsorption. Finally, TAA-MICP was used as sensitive layer in an original Electrochemical Surface Acoustic Wave sensor (ESAW) which enabled simultaneous coupled gravimetric and electrochemical measurements.
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Cao, Yihong. "Sugar and Peptide mimics for SPR Characterization of autoantibodies in monoclonal gammopathy." Phd thesis, Université de Cergy Pontoise, 2013. http://tel.archives-ouvertes.fr/tel-00877262.
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IgM monoclonal gammopathy is a common age-related demyelinating sensory and motor polyneuropathy. It has been shown to be associated with antibodies against myelin-associated glycoproteins (MAG/SGPG). The HNK-1 carbohydrate epitope is a terminal 3-sulfo-glucuronyl residue attached to lactosamine structures and it is shared both in MAG and SGPG (SO4-3-GlcA(β1-3)Gal-(β1-4)GlcNAc(β1-3)Gal-(β1-4)Glcβ(1-1′)Cer). It is mostly expressed in the nervous system and plays an important role in preferential motor reinnervation. Nevertheless, the HNK-1 epitope is difficult to be isolated and synthesized and diagnostic assays used in the clinics are not always reproducible and reliable. Therefore in our study, our goal is to identify a simple synthetic diagnostic tool (peptide or monosaccharide), mimetic of the HNK-1 epitope, able to recognize antibodies in neurogammopathies sera by Surface Plasmon Resonance to be used in earlier stage patients and possibly to monitor disease activity. For this reason, we firstly tried to synthesize this trisaccharide and then we achieved the synthesis of its terminal monosaccharides with different function groups (octyl glucopyranoside, octyl glucuronic acid, octyl 3-O-sulfo-glucuronic acid and 8-amino octyl 3-O-sulfo-glucuronic acid). Then 10 linear and cyclic peptides conformationally and/or structurally mimicking HNK-1 were also synthesized (LSETTI, LSETTl, cyclo(-TTILSE-), cyclo(-TTlLSE-), cyclo(-TKTlLSE-), cyclo(-TETKlLSE-), TYTKlLSE, TY(SO3)TKlLSE, cyclo(-TYTKlLSE-) and cyclo(-TY(SO3)TKlLSE-)). The SPR kinetic binding affinities of all these sugar and peptide mimics were studied with commercial anti HNK-1 antibody using Biacore. Moreover, mimics with highest binding affinities were chosen for antigen-antibody interaction study in IgM gammopathy patients' serum.
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Silva, Alineaurea Florentino. "Uso de resíduo orgânico na produção de mandioca em transição agroecológica, no Projeto Pontal, Petrolina-PE." Universidade Federal da Paraíba, 2017. http://tede.biblioteca.ufpb.br:8080/handle/tede/9159.
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The soils of most of the rain-dependent areas farms of the semiarid region of the northeastern Brazil have low levels of elements such as nitrogen and phosphorus, hampering the achievement of results of production that allow the satisfactory maintenance of the agricultural activity in these areas. As a result, year after year the expected yields become increasingly rare and many farmers no longer believe in the viability of cultivation of some species, even those that have historically occupied spaces in these important properties, such as maize, beans and cassava. Cassava is a species of great importance in semi-arid environments, presenting great versatility in the production of fresh and processed foods and fodder. The use of organic residues from the properties for soil fertilization and improvement of growth of the vegetal species is one of the internationally recommended practices for a sustainable ecologically based agriculture. The objective of this work was to evaluate cassava (Manihot esculenta cranz) production and soil fertility with the use of organic residue in agroecological transition in the Pontal Project, Petrolina-PE. Semistructured interviews, soil collection, of residues and of the production in the communities were held in the communities Vira Beiju, Lajedo and Amargosa. The soil analyzes were carried out at Embrapa Semiarid and revealed the need for soil acidity correction (pH between 4,2 and 5,5) in all communities, addition of sources of phosphorus (P available< 3,8 mg.dm-3), organic matter (<5,5 g.kg-1) and zinc (< 6,95 mg.dm-3), especially in community Vira Beiju. Various activities that generate agricultural waste that can be used in local agriculture were identified, but in this study period (drought) only goat manure was found in greater quantity (5,0m3 per month), in all communities, being sold for obtaining income. Livestock production was one the most generating of waste, along with the crops, also mentioned as big generators of residues, by most of the interviewee (89%). The stable was the place with highest generation of residues in the property, during the study period (88.9 %). The response of the plant to the use of the tested residue (manure) or phosphorus application has been directly related to the soil type and hydric conditions during the plant cycle, being these conditions highly variable in this study in the three communities studied. The correction of the soil showed significant results when associated to the use of manure, being very promising to increase the yield of cassava in an agroecological transition system.
Os solos da maioria das propriedades de áreas dependentes de chuva, da região semiárida do nordeste brasileiro, possuem baixos teores de elementos como nitrogênio e fósforo, dificultando o alcance de resultados de produção que permitam a manutenção satisfatória da atividade agrícola nessas áreas. Como consequência, ano após ano, as safras esperadas tornam-se cada vez mais raras e muitos agricultores passam a não mais acreditar na viabilidade do cultivo de algumas espécies, mesmo aquelas que historicamente têm ocupado espaços importantes nessas propriedades, como milho, feijão e mandioca. A mandioca é uma espécie de grande importância nos ambientes semiáridos, apresentando grande versatilidade na produção de alimentos in natura e processados e forragem. O uso de resíduos orgânicos das propriedades para fertilização do solo e melhoria das condições de crescimento das espécies vegetais é uma das práticas internacionalmente preconizadas para uma agricultura de base ecológica. O presente trabalho teve como objetivo avaliar a produção de mandioca (Manihot esculenta cranz) e a fertilidade do solo com uso de resíduo orgânico, em transição agroecológica no Projeto Pontal, Petrolina-PE. Foram realizadas entrevistas semiestruturadas, coleta de solo, de resíduos e da produção nas comunidades Vira Beiju, Lajedo e Amargosa. As análises do solo e dos resíduos orgânicos encontrados nas propriedades foram realizadas na Embrapa Semiárido e revelaram a necessidade de correção da acidez (pH entre 4,2 e 5,5) em todas as comunidades, adição de fontes de fósforo (P disponível<3,8mg.dm-3), matéria orgânica (<5,5 g.kg-1) e zinco (<6,95 mg.dm-3), principalmente na Comunidade Vira Beiju. Foram identificadas diversas atividades geradoras de resíduos que podem ser utilizados na agricultura local, porém no período avaliado (estiagem) apenas o esterco caprino foi encontrado em maior quantidade (5,0m3/mês), em todas as comunidades, sendo comercializado para obtenção de renda. A criação de animais foi uma das atividades mais geradora de resíduos, junto com os cultivos, também apontados como grandes geradores de resíduos, pela maioria dos entrevistados (89%). O curral foi o local de maior geração de resíduos na propriedade, no período avaliado (88,9%). A resposta da planta ao uso do resíduo testado (esterco) ou aplicação de fósforo esteve diretamente relacionado ao tipo de solo e condições hídricas no período do ciclo da planta, sendo estas condições altamente variáveis no presente estudo nas três comunidades trabalhadas. A correção do solo mostrou resultados significativos quando associado ao uso do esterco, sendo bastante promissor para elevar a produtividade da mandioca em sistema de transição agroecológica.
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Motakef, Shahrnaz 1968. "Optical characterization of wet chemically derived organic-inorganic hybrid (polyceram) films." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282206.
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The present investigation is concerned with the processing and characterization of sol-gel derived Polyceram materials. Polycerams, a new class of multi-functional materials, are organic-inorganic composite materials where the components are combined at or near the molecular level. In this dissertation, particular emphasis is attributed to the synthesis, processing and characterization of thin films of Polycerams. Numerous optical characterization techniques were performed to study the passive properties of Polycerams, including index of refraction, optical attenuation, UV transmission and surface embossing. Dielectric waveguides of superior optical quality were obtained and Polycerams proved to be surface patternable with near-perfect shape replication abilities. The above properties are discussed in conjunction with a scattering model which explains the structural homogeneity of Polycerams. Optical losses below 0.15 dB/cm and the simple fabrication of channel waveguides and lenses via surface embossing render Polycerams highly suitable candidates for today's integrated optics technology.
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Martinis, Bruno Spinosa de. "Caracterização química e biológica das partículas respiráveis (PM10) do material particulado atmosférico coletado em um sítio urbano da cidade de São Paulo." Universidade de São Paulo, 1997. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-11092014-164310/.
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A região metropolitana de São Paulo apresenta um intenso e desordenado processo de urbanização e industrialização. Devido a estes processos, a região sofre grandes problemas de poluição atmosférica, agravados em certos meses devido às dificuldades de dispersão dos poluentes. Estes poluentes causam efeitos indesejáveis ao meio ambiente e à saúde humana. A caracterização química e a avaliação da atividade mutagênica desses compostos presentes no material particulado atmosférico (MPA) é um grande desafio analítico e, é de extrema importância para o conhecimento das possíveis correlações entre os poluentes, os efeitos deletérios à saude e as fontes de emissão. Os objetivos deste trabalho foram caracterizar quimicamente os extratos orgânicos polares e semi-polares do material particulado atmosférico da cidade de São Paulo e avaliar sua atividade mutagênica. O MPA é uma mistura complexa de compostos orgânicos e inorgânicos presentes em diferentes faixas de concentrações. Devido a esta complexidade, o fracionamento químico do extrato orgânico deste material é necessário para isolar classes de compostos ou compostos individuais, permitindo a identificação e quantificação dos mesmos. Os resultados obtidos pelas diversas técnicas analíticas empregadas mostraram que os extratos em diclorometano e acetona contém inúmeros compostos orgânicos pertencentes a diferentes classes, tais como hidrocarbonetos policíclicos aromáticos, quinolinas, cetonas, piridinas, furanos, aldeídos, amidas e aminas, sendo que alguns destes compostos são considerados agentes genotóxicos. O extrato em DCM contem a maior massa e sua composição é quase exclusivamente orgânica. Já o extrato em ACE contem além dos orgânicos, espécies inorgânicas. Testes de mutagenicidade indicaram que o MPA coletado na cidade de São Paulo apresenta uma atividade mutagênica relativamente alta quando comparada a outros centros urbanos.São Paulo metropolitan area presents an intense and chaotic process of urbanization and industrialization. Due to this processes, this region has big atmospheric pollution problem. In certain months of the year, this problem gets worse due to the unfavorable dispersion conditions. The pollutants cause undesirable effects to the environment and to the human health. The chemical characterization and the mutagenic activity evaluation of the compounds present on the atmospheric particulate matter APM) represents an analytical challenge and it is very important for understanding of the correlation among pollutants, health hazards and emission sources. The goal of this work was chemically characterize the polar and moderately polar organic extracts from the APM collected in São Paulo city and to evaluate their mutagenic activity. The APM is a complex mixture of organic and inorganic compounds present in large range of concentration. Due to this complexity, the chemical fractionation of these organic extracts is necessary to isolate classes or individual compounds, to allow their identification and quantification. The results obtained using different analytical techniques demonstrated that the dichlorometane and acetone extracts has several organic compounds belonging to different classes, such as, polycyclic aromatic hydrocarbons, quinolines, ketones, pyridines, furanes, aldehydes, amides and amines. Some of these compoundsa are considered carcinogens and/or mutagens. The dichloromethane extract presented the highest mass yield and its composition is almost exclusively organic. The acetone extract has organic and inorganic species. Mutagenicity tests revealed that the APM from São Paulo city presented a have relatively high mutagenic activity when compared to other urban regions.
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Salque-Moreton, Guillaume. "Etude d'aérosol atmosphérique par spectrométrie de masse à très haute résolution." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU013/document.
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L'aérosol atmosphérique a des effets sur le changement climatique global et un impact sanitaire non-négligeables. Dans l'aérosol atmosphérique terrestre, les composés organiques représentent une fraction importante. Du fait de l'extrême complexité de cette fraction organique et des processus dynamiques qui l'animent, une fraction non négligeable de celle-ci n'est pas clairement identifiée à ce jour malgré des techniques d'analyses toujours plus nombreuses. Dans cette thèse, nous avons voulu explorer la richesse d'information fournie par une technique innovante : la spectrométrie de masse à haute résolution (HRMS). La haute résolution du LTQ-Orbitrap fournit une extrême précision sur la masse des molécules analysées et permet d'en identifier les formules brutes. Tout d'abord, nous avons utilisé cette nouvelle méthode de caractérisation afin d'élucider en laboratoire des mécanismes de production de l'aérosol se déroulant en phase aqueuse. Associée à une caractérisation par RMN, la HRMS nous permet d'identifier des voies de fabrication de composés de faible poids moléculaires (acides carboxyliques, aldéhydes, cétone) ainsi que des composés à haut poids moléculaire : les oligomères formés se transforment en HULIS au cours de leur vieillissement. Le fait que la méthacroléine (MACR) et la méthyl-vinyl-cétone (MVK), les deux principaux produits d'oxydation de l'isoprène, forment des AOS en phase aqueuse avait été précédemment montré. Ce travail montre que les précurseurs des AOS sont différents selon l'isomère et que les séries d'oligomères formées atteignent 1400 Da.. L'étude HRMS des produits permet de proposer un mécanisme radicalaire d'oligomérisation de la MVK. L'analyse HRMS des produits de la MACR montre qu'en plus du mécanisme valable pour la MVK, la réactivité de la MACR engendre co-polymérisation et production d'Hulis. Une signature HRMS des Hulis a été mise en évidence. Ensuite, nous avons utilisé les méthodes de traitement de données HRMS pour tenter de les appliquer à l'identification d'aérosol ambiant. Les composés organiques représentent la fraction majeure des particules de l'aérosol atmosphérique ; une grande partie reste mal identifiée. Une compréhension détaillée des sources et des procédés de transformations est nécessaire. L'investigation de la composition chimique des particules de matière fine et ultrafine peut être apporter par HRMS. L'ESI-Orbitrap apporte une description moléculaire qui détermine les propriétés chimiques et physiques de l'aérosol organique. Les particules ont été échantillonnées selon leur taille respective. Les prélèvements ont été fait à Grenoble en été et en hiver. Une comparaison saisonnière permet d'identifier des signatures chimiques différentes. Enfin, une intercomparaison est établie avec des échantillons d'une troisième campagne prélevées en proximité routière: MOCOPOAtmospheric aerosol has an important impact on the radiative balance of Earth. Organics compounds represent the major fraction of atmospheric aerosol particles; a large part is still not well characterized. A detailed understanding of the sources, transformations processes and fates of organics aerosols is needed. This work investigates the ability of the ESI-Orbitrap to characterize organics molecules of aerosol. Firstly, experimental and analytical methods were developed to unveil mechanistic ambiguities that were previously shown. Methacrolein (MACR) and methyl vinyl ketone (MVK) (the two main gas phase atmospheric oxidation products of isoprene) were known to form oligomers and secondary organic aerosol (SOA) upon aqueous phase OHoxidation and subsequent water evaporation. For the two precursors, ESI-MS analysis of the reacting solutions brought clear evidence for the formation of oligomer systems having a mass range of up to 1400 Da.. Taking advantage of the regularities observed in the oligomer systems, the ESI-HRMS data were used to propose stoichiometries for more than 75% of the observed signal. Moreover, we show here that MACR oligomers aging give rise to HULIS production. In addition, global estimates of secondary organic aerosol (SOA) formation flux show that current descriptions miss a large fraction of the sources. This gaping underestimation has been linked to a poor understanding of aerosol functionalization in the atmosphere and lead to the formation of a new conceptual framework for the description of the aerosol, based on volatility versus polarity plots. This new framework is almost exclusively based on High Resolution Time of Flight Aerosol Mass Spectrometer(HR-Tof-AMS) data, as this instrument gives access to average H:C, N:C and O:C ratios for the bulk aerosol. The AMS estimates for O:C and H:C ratios are thus based on heavy fragmentation of organics followed by stoichiometry attribution on those fragments. Given the resolution of the HR-ToF-AMS, such an attribution is not feasible above a certain mass, making fragmentation a necessary aspect of the measurement. Conversely, Orbitrap-HRMS provide a resolution of 100,000 at m/z 400, with a mass range 50 – 2000 amu, enabling stoichiometry retrieval up to higher masses than the AMS. Coupled to a “soft” electrospray ionization method, Orbitrap-HRMS gives O:C and H:C ratios on entire molecules in the analysed mixture. We used samples from three contrasted field campaigns: the two first at an urban kerbside site in summer and in winter, the third one in the roadway vicinity (Grenoble, France). Accelerated Solvent Extraction provides a clear overview of the chemical composition of organic extracts from aerosol particles collected at different season at an urban site. The elemental composition was obtained within 2-5 ppm, on the range 150-300 m/z. However, this study shows that both ionization polarity were needed to get a complete picture of the chemical composition of the samples. We showed that Esi-Orbitrap-HRMS allows to compute a statistical distribution of the elementary ratios that is different from a simple average value. Keywords: HRMS, SOA
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Charbonneau, Micaël. "Etude et développement de points mémoires résistifs polymères pour les architectures Cross-Bar." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT116/document.
Full textAbstract:
Ces dix dernières années, les technologies de stockage non-volatile Flash ont joué un rôle majeur dans le développement des appareils électroniques mobiles et multimedia (MP3, Smartphone, clés USB, ordinateurs ultraportables…). Afin d’améliorer davantage les performances, augmenter les capacités et diminuer les coûts de fabrication, de nouvelles solutions technologiques sont aujourd’hui étudiées pour pouvoir compléter ou remplacer la technologie Flash. Citées par l’ITRS, les mémoires résistives polymères présentent des caractéristiques très prometteuses : procédés de fabrication à faible coût et possibilité d’intégration haute densité au dessus des niveaux d’interconnexions CMOS ou sur substrat souple. Ce travail de thèse a été consacré au développement et à l'étude des mémoires résistifs organiques à base de polymère de poly-méthyl-méthacrylate (PMMA) et de molécules de fullerènes (C60). Trois axes de recherche ont été menés en parallèle: le développement et la caractérisation physico-chimique de matériaux composites, l’intégration du matériau organique dans des structures de test spécifiques et la caractérisation détaillée du fonctionnement électrique des dispositifs et des performances mémoiresOver the past decade, non-volatile Flash storage technologies have played a major role in the development of mobile electronics and multimedia (MP3, Smartphone, USB, ultraportable computers ...). To further enhance performances, increase the capacity and reduce manufacturing costs, new technological solutions are now studied to provide complementary solutions or replace Flash technology. Cited by ITRS, the polymer resistive memories present very promising characteristics: low cost processing and ability for integration at high densities above CMOS interconnections or on flexible substrate. This PhD specifically focused on the development and study of composite material made of Poly-Methyl-Methacrylate (PMMA) polymer resist doped with C60 fullerene molecules. Studies were carried out on three different axes in parallel: Composite materials development & characterization, integration of the organic material in specific test structure and advanced devices and finally detailed electrical characterization of memory cells and performances analysis