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1

Dahlgren, Patrik, Emil Heehrle, and Jim Persson. "Analys av Örkelljunga Utbildningscentrums IT-miljö." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-23204.

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I dagens samhälle där tillgången till information är nästintill obegränsad och nätverkfinns överallt ökar kraven på IT-säkerhet. Gratis programvaror och information omhur man använder dessa finns enkelt tillgängliga för vem som helst på Internet idag.Då många av dessa programsviter har full support och de är mycket användarvänligainnebär det också att fler kan utföra intrång och attacker mot olika IT-miljöer utanatt behöva inneha expertis inom området. Ett hjälpmedel mot dessa hot ärpenetrationstesting, där man kan identifiera eventuella brister och sårbarheter i ettgivet IT-system.Den här rapportens mål har varit att utreda om Örkelljunga Utbildningscentrums ITsäkerhetstår i proportion till känsligheten på informationen som de innehar ochbehandlar.Detta har gjorts genom ett penetrationstest, där man på plats har skannat skolansnätverk efter sårbarheter och möjliga intrångsvägar.Därefter har sårbarheterna utvärderats och rankats efter hur kritiska de anses varaoch utifrån detta teoretiskt bevisat hur man som attackerare hade kunnat gå till vägaför att komma åt eller förstöra känslig information.Resultaten visade på ett flertal kritiska brister som vid närmare analys hade kunnatutnyttjas för att ta sig in i systemet och eventuellt komma åt känslig information.Slutsats blev därför att Örkelljunga Utbildningscentrums IT-miljö för närvarande intehar tillräcklig säkerhet i proportion till känsligheten på information som de innehar.
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2

Berntsson, Marcus. "Penetrationstest." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-12157.

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Det här arbete behandlar grunderna i penetrationstestning, vilket är en metod föratt kontrollera säkerheten i datorer och nätverk genom att försöka sätta in sig isamma tankesätt och metoder som en potentiell angripare kan ha.Den teoritiska delen går igenom processen för hur ett penetrationstest kan gå tilloch vad som är viktigt att veta och att tänka på under penetrationstestet.Det presenteras även några populära och användbara verktyg som kananvändas för penetrationstestning, nämligen Nmap, Backtack, Nessus ochMetasploit, samt en nogrann beskrivning av några av de mest vanligtvisförekommande allvarliga sårbarheterna.I genomförandedelen utförs ett penetrationstest i en labmiljö, och sätter då deninformation i den teoritiska delen i praktik. De verktygen som används gåsigenom mer detaljerat och olika metoder för att använda dessa verktyg ipenetrationstestningssyfte testas.Penetrationstestet gås igenom stegvis, och börjar med att hitta maskiner pånätverket och även hitta detaljerad information och möjligheter för angrepp. Deninformationen används sedan för att hitta sårbarheter i maskinerna, och slutligenutnyttjas dessa sårbarheter för att installera ett remote-access program och gekontrollen till den angripande datorn.
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3

Šimkovič, Peter. "Návrh auditního systému pro kontrolu systémů a služeb v počítačové síti." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2021. http://www.nusl.cz/ntk/nusl-444575.

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This diploma thesis deals with the design of an audit system with which it will be possible to detect security gaps in a computer network. Detection will take place on the basis of checking predefined ports and services running on them. Based on the output of the audit system, possible measures and rules necessary to correct security gaps will be proposed. The system itself will be designed to ensure its easy implementation for any customer.
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4

Ashe, James Patrick. "A vulnerability assessment of the East Tennessee State University administrative computer network." [Johnson City, Tenn. : East Tennessee State University], 2004. http://etd-submit.etsu.edu/etd/theses/available/etd-0301104-151512/unrestricted/AsheJ030204b.pdf.

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Thesis (M.S.)--East Tennessee State University, 2004.
Title from electronic submission form. ETSU ETD database URN: etd-0301104-151512. Includes bibliographical references. Also available via Internet at the UMI web site.
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5

Linnér, Samuel. "Graybox-baserade säkerhetstest : Att kostnadseffektivt simulera illasinnade angrepp." Thesis, Växjö University, School of Mathematics and Systems Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2299.

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Att genomföra ett penetrationstest av en nätverksarkitektur är komplicerat, riskfyllt och omfattande. Denna rapport utforskar hur en konsult bäst genomför ett internt penetrationstest tidseffektivt, utan att utelämna viktiga delar. I ett internt penetrationstest får konsulten ofta ta del av systemdokumentation för att skaffa sig en bild av nätverksarkitekturen, på så sätt elimineras den tid det tar att kartlägga hela nätverket manuellt. Detta medför även att eventuella anomalier i systemdokumentationen kan identifieras. Kommunikation med driftansvariga under testets gång minskar risken för missförstånd och systemkrascher. Om allvarliga sårbarheter identifieras meddelas driftpersonalen omgå-ende. Ett annat sätt att effektivisera testet är att skippa tidskrävande uppgifter som kommer att lyckas förr eller senare, t.ex. lösenordsknäckning, och istället påpeka att orsaken till sårbarheten är att angriparen har möjlighet att testa lösenord obegränsat antal gånger. Därutöver är det lämpligt att simulera vissa attacker som annars kan störa produktionen om testet genomförs i en driftsatt miljö.

Resultatet av rapporten är en checklista som kan tolkas som en generell metodik för hur ett internt penetrationstest kan genomföras. Checklistans syfte är att underlätta vid genomförande av ett test. Processen består av sju steg: förberedelse och planering, in-formationsinsamling, sårbarhetsdetektering och analys, rättighetseskalering, penetrationstest samt summering och rapportering.


A network architecture penetration test is complicated, full of risks and extensive. This report explores how a consultant carries it out in the most time effective way, without overlook important parts. In an internal penetration test the consultant are often allowed to view the system documentation of the network architecture, which saves a lot of time since no total host discovery is needed. This is also good for discovering anomalies in the system documentation. Communication with system administrators during the test minimizes the risk of misunderstanding and system crashes. If serious vulnerabilities are discovered, the system administrators have to be informed immediately. Another way to make the test more effective is to skip time consuming tasks which will succeed sooner or later, e.g. password cracking, instead; point out that the reason of the vulnerability is the ability to brute force the password. It is also appropriate to simulate attacks which otherwise could infect the production of the organization.

The result of the report is a checklist by means of a general methodology of how in-ternal penetration tests could be implemented. The purpose of the checklist is to make it easier to do internal penetration tests. The process is divided in seven steps: Planning, information gathering, vulnerability detection and analysis, privilege escalation, pene-tration test and final reporting.

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6

Andersson, Dorothea. "Simulation of industrial control system field devices for cyber security." Thesis, KTH, Elkraftteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202405.

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Industrial Control Systems (ICS) are an integral part of modernsociety, not least when it comes to controlling and protecting criticalinfrastructure such as power grids and water supply. There is a need to testthese systems for vulnerabilities, but it is often difficult if not impossible to doso in operational real time systems since they have been shown to be sensitiveeven to disturbances caused by benign diagnostic tools. This thesis exploreshow ICS field devices can be simulated in order to fool potential antagonists,and how they can be used in virtualized ICS for cyber security research. 8different field devices were simulated using the honeypot daemon Honeyd,and a generally applicable simulation methodology was developed. It was alsoexplored how these simulations can be further developed in order to functionlike real field devices in virtualized environments.
Industriella informations- och styrsystem utgör en viktig delav vårt moderna samhälle, inte minst när det gäller kontroll och skydd avkritisk infrastruktur som elnät och vattenförsörjning. Det finns stora behov avatt säkerhetstesta dessa typer av system, vilket ofta är omöjligt iproduktionsmiljöer med realtidskrav som är erkänt känsliga för störningar, tilloch med från vanligt förekommande analysverktyg. Denna rapport presenterarhur vanliga komponenter i industriella informations- och styrsystem kansimuleras för att lura potentiella antagonister, och hur de kan användas ivirtualiserade styrsystem för cybersäkerhetsforskning. 8 olika komponentersimulerades med hjälp av Honeyd, och en generellt applicerbarsimuleringsmetodik utvecklades. Hur dessa simuleringar kan vidareutvecklasför att fungera som riktiga styrsystemskomponenter i virtualiserade miljöer harockså undersökts.
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7

Pokorný, Josef. "Určení pozice útočníka při pokusu o neoprávněný přístup do operačního systému." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220320.

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My master thesis estimates physical location of potential operating system attacker. It deals with basic methods of attack against operating system: spam and viruses, searching the Internet, port scanning and operating system detection. The thesis disserts about a port scanner Nmap, a port scanning detector Scanlogd and about a system log watch Swatch. The thesis deals with geolocation methods of potential operating system attacker. These geolocation methods are divided into an active and a passive types. The active methods measure delay in the Internet. The passive methods query the database. I mentioned a freely accessible Whois database and MaxMind databases. There is a program developed and practically tested. The program simulates an attacker beginning an attack by scanning ports of target machine. The program works with dataset of real IP addresses. The program also detects the attack against operating system. The real and evaluated location of an attacker is got and then shown in a map. At the end there is a review of results and data comparison with colleagues.
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8

Giorgino, Giuseppe. "Analisi di attacchi basati su port scanning." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8236/.

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Nella tesi vengono presentate le analisi, con le relative considerazioni, di attacchi basati su port scanning, in particolar modo ci si sofferma sull'utilizzo di risorse, come impiego di CPU, di banda, ecc., in relazione alle diverse tecniche adoperate. Gli attacchi sono stati rivolti attraverso l'applicativo Nmap contro una rete di honeypot, gestiti e configurati attraverso il software Honeyd. Inoltre vengono fornite tutta una serie di conoscenze necessarie al lettore, le quali risulteranno essenziali per poter affrontare tutti gli argomenti trattati, senza doversi necessariamente informare da altre fonti.
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9

Simons, William R. "The challenges of network security remediation at a regional university." [Johnson City, Tenn. : East Tennessee State University], 2005. http://etd-submit.etsu.edu/etd/theses/available/etd-0209105-075524/unrestricted/SimonsW022105f.pdf.

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Thesis (M.S.)--East Tennessee State University, 2005.
Title from electronic submission form. ETSU ETD database URN: etd-0209105-075524 Includes bibliographical references. Also available via Internet at the UMI web site.
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10

Holešinský, Jan. "Systém pro správu malé podnikové sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2014. http://www.nusl.cz/ntk/nusl-236085.

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The goal of this thesis is to design and to implement the active and passive monitoring and control system for small company with emphasis on the most automated control and deployment in a production network. System is appropriately designed using the Nette framework and scripting language Perl which is suitable for control computer systems and networks.
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11

Šnajdr, Václav. "Webová aplikace pro testování zranitelností webového serveru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442387.

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The Master’s Thesis deals with the design and implementation of a web application for testing the security of SSL/TLS protocols on a remote server. The web application is developed in the Nette framework. The theoretical part describes SSL/TLS protocols, vulnerabilities, recommendations and technologies used in the practical part. The practical part is devoted to the creation of a web application with the process of using automatic scripts to test and display the results on the website with a rating of A+~to~C. The web application also displays a list of detected vulnerabilities and their recommendations.
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12

Rahman, Farhana. "Performance evaluation of 4.75-mm NMAS Superpave mixture." Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3893.

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13

Shooter, Andrew James. "Living free radical polymerisation." Thesis, University of Warwick, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263817.

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Gauravaram, Praveen Srinivasa. "Cryptographic hash functions : cryptanalysis, design and applications." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16372/.

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Cryptographic hash functions are an important tool in cryptography to achieve certain security goals such as authenticity, digital signatures, digital time stamping, and entity authentication. They are also strongly related to other important cryptographic tools such as block ciphers and pseudorandom functions. The standard and widely used hash functions such as MD5 and SHA-1 follow the design principle of Merkle-Damgard iterated hash function construction which was presented independently by Ivan Damgard and Ralph Merkle at Crypto'89. It has been established that neither these hash functions nor the Merkle-Damgard construction itself meet certain security requirements. This thesis aims to study the attacks on this popular construction and propose schemes that offer more resistance against these attacks as well as investigating alternative approaches to the Merkle-Damgard style of designing hash functions. This thesis aims at analysing the security of the standard hash function Cellular Authentication and Voice Encryption Algorithm (CAVE) used for authentication and key-derivation in the second generation (2G) North American IS-41 mobile phone system. In addition, this thesis studies the analysis issues of message authentication codes (MACs) designed using hash functions. With the aim to propose some efficient and secure MAC schemes based on hash functions. This thesis works on three aspects of hash functions: design, cryptanalysis and applications with the following significant contributions: * Proposes a family of variants to the Damgard-Merkle construction called 3CG for better protection against specific and generic attacks. Analysis of the linear variant of 3CG called 3C is presented including its resistance to some of the known attacks on hash functions. * Improves the known cryptanalytical techniques to attack 3C and some other similar designs including a linear variant of GOST, a Russian standard hash function. * Proposes a completely novel approach called Iterated Halving, alternative to the standard block iterated hash function construction. * Analyses provably secure HMAC and NMAC message authentication codes (MACs) based on weaker assumptions than stated in their proofs of security. Proposes an efficient variant for NMAC called NMAC-1 to authenticate short messages. Proposes a variant for NMAC called M-NMAC which offers better protection against the complete key-recovery attacks than NMAC. As well it is shown that M-NMAC with hash functions also resists side-channel attacks against which HMAC and NMAC are vulnerable. Proposes a new MAC scheme called O-NMAC based on hash functions using just one secret key. * Improves the open cryptanalysis of the CAVE algorithm. * Analyses the security and legal implications of the latest collision attacks on the widely used MD5 and SHA-1 hash functions.
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Gauravaram, Praveen. "Cryptographic hash functions : cryptanalysis, design and applications." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16372/1/Praveen_Gauravaram_Thesis.pdf.

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Cryptographic hash functions are an important tool in cryptography to achieve certain security goals such as authenticity, digital signatures, digital time stamping, and entity authentication. They are also strongly related to other important cryptographic tools such as block ciphers and pseudorandom functions. The standard and widely used hash functions such as MD5 and SHA-1 follow the design principle of Merkle-Damgard iterated hash function construction which was presented independently by Ivan Damgard and Ralph Merkle at Crypto'89. It has been established that neither these hash functions nor the Merkle-Damgard construction itself meet certain security requirements. This thesis aims to study the attacks on this popular construction and propose schemes that offer more resistance against these attacks as well as investigating alternative approaches to the Merkle-Damgard style of designing hash functions. This thesis aims at analysing the security of the standard hash function Cellular Authentication and Voice Encryption Algorithm (CAVE) used for authentication and key-derivation in the second generation (2G) North American IS-41 mobile phone system. In addition, this thesis studies the analysis issues of message authentication codes (MACs) designed using hash functions. With the aim to propose some efficient and secure MAC schemes based on hash functions. This thesis works on three aspects of hash functions: design, cryptanalysis and applications with the following significant contributions: * Proposes a family of variants to the Damgard-Merkle construction called 3CG for better protection against specific and generic attacks. Analysis of the linear variant of 3CG called 3C is presented including its resistance to some of the known attacks on hash functions. * Improves the known cryptanalytical techniques to attack 3C and some other similar designs including a linear variant of GOST, a Russian standard hash function. * Proposes a completely novel approach called Iterated Halving, alternative to the standard block iterated hash function construction. * Analyses provably secure HMAC and NMAC message authentication codes (MACs) based on weaker assumptions than stated in their proofs of security. Proposes an efficient variant for NMAC called NMAC-1 to authenticate short messages. Proposes a variant for NMAC called M-NMAC which offers better protection against the complete key-recovery attacks than NMAC. As well it is shown that M-NMAC with hash functions also resists side-channel attacks against which HMAC and NMAC are vulnerable. Proposes a new MAC scheme called O-NMAC based on hash functions using just one secret key. * Improves the open cryptanalysis of the CAVE algorithm. * Analyses the security and legal implications of the latest collision attacks on the widely used MD5 and SHA-1 hash functions.
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Brown, Nicole Robitaille. "Understanding the Role of N-Methylolacrylamide (Nma) Distribution in Poly(Vinyl Acetate) Latex Adhesives." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26446.

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This work addresses the distribution of N-methylolacrylamide (NMA) units in crosslinking poly(vinyl acetate) (PVAc) adhesives. In this case, distribution refers to the three potential locations of polymerized NMA units in a latex: the water-phase, the surface of polymer particles, and the core of the polymer particles. The objective is to identify the distribution of NMA in three latices and to determine whether NMA distribution correlates with durability related performance. NMA distribution was studied via a series of variable temperature solution NMR experiments, while the durability-related performance was studied via mode I fracture mechanics tests. Studying the distribution of NMA required the use of isotopically labeled NMA. Both 15N-NMA and 13C, 15N-NMA were synthesized. Three NMA/vinyl acetate (VAc) latices were prepared. The NMA feed strategy was varied during each of the three emulsion copolymerizations. Latex characterization methods including differential scanning calorimetry (DSC), rheometry, particle size analysis, and scanning electron microscopy (SEM) were used to study the three latices. The solution NMR method to identify NMA distribution was performed on untreated latices and on washed latices. Washing techniques included membrane dialysis and centrifugation. Results revealed that the three latices had different NMA distributions, and that the distributions were related to the expected differences in microstructure. Latex 3 had ~ 80% core-NMA, while Latex 2 had ~ 80% surface-NMA. Latex 1 had a high proportion of surface-NMA (~60%), but also had the highest proportion of water-phase NMA (~ 20%). This high proportion of water-phase NMA could be responsible for the unique morphology Latex 1 exhibited in SEM studies. Mode I opening fracture mechanics studies were used to study adhesive performance. Specimens were analyzed after exposure to accelerated aging treatments. Latex 2 and Latex 3 exhibited very similar results, despite having very different NMA distributions. All three latices showed good durability related performance. In Latex 2 and Latex 3, the critical strain energy release rates (Gc) after accelerated aging treatments were statistically the same as the Gc of the control specimens. The most interesting finding was that the Latex 1 Gc values were significantly higher after accelerated aging. Latex 1 also had the highest proportion of water-phase NMA. Bondline images and SEM micrographs both indicated that the integrity of Latex 1 was least affected by the accelerated aging treatments.
Ph. D.
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17

Holzer, Schaa Kathleen Ingrid. "Cuantificación de Bacterias en Procesos de Biolixiviación mediante NMP-PCR." Tesis, Universidad de Chile, 2007. http://www.repositorio.uchile.cl/handle/2250/104561.

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Pompei, Leonardo Mendonça. "Estudo de sistema de absorção de 1,3-butadieno em NMP." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-04072016-153736/.

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O propósito deste trabalho foi o desenvolvimento de um procedimento simulador de processo reproduzindo a etapa de destilação extrativa de uma unidade de extração de butadieno a partir de uma corrente de hidrocarbonetos na faixa de quatro átomos de carbono, através da adição do solvente n-metil-2- pirrolidona (NMP). Os resultados obtidos foram comparados e validados com dados de processo obtidos por uma unidade industrial de extração de butadieno. O aprofundamento nos conceitos do processo de separação através de uma ferramenta em simulador de processo capaz de predizer condições de operação permitiu avaliações de aumento de capacidade. A capacidade dos elementos internos dos equipamentos envolvidos na separação pode ser avaliada e a identificação do ponto inicial de engargalamento da unidade foi possível. O procedimento proposto também permite reduzir incertezas para identificação de novos pontos de engargalamento a partir de uma nova configuração dos elementos internos identificados como ineficientes com a elevação de carga processada.
The purpose of this study was the development of a model using a commercial process simulator software in order to reproduce the extractive distillation step of a butadiene extraction unit from a hydrocarbon stream by the addition of the solvent n- methyl-2-pyrrolidone (NMP). The results obtained from the simulations were compared with process data from an operational butadiene extraction unit. The knowledge of the separation process due the model should predict operating conditions allowing revamps on the actual asset. The internals capacity for the equipment involved in the separation could be evaluated and units bottlenecks points should be identified.
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Mougnier, Sébastien-Jun. "Copolymères semi-conducteurs à architectures variées : de l'ingénierie macromoléculaire à l'électronique organique." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14675/document.

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A une époque où les technologies nouvelles fleurissent chaque jour, un domaine particulier se détache : l’électronique organique. Par son utilité et sa facilité de mise en œuvre, l’électronique organique affiche de grandes promesses pour l’avenir. Dans le but d’améliorer le procédé de fabrication et la durée de vie de ces dispositifs, le travail de cette thèse s'est focalisé sur la synthèse de copolymères à architectures variées à base de poly(3-hexylthiophène) (P3HT). Après avoir exposé les problématiques et objectifs de la thèse dans une première partie, la synthèse de différents précurseurs P3HT est décrite. Ces matériaux représentent la base des travaux présentés dans cet ouvrage. Dans un premier temps, l'optimisation de la synthèse des copolymères à blocs rigide-flexible a été réalisée en suivant une stratégie adaptée pour une application en électronique organique. La conception de nouveaux matériaux semi-conducteurs à architectures ramifiées est traitée par la suite. Enfin, le dernier chapitre porte sur l'intégration d’un copolymère, le P3HT-b-Poly(4vinylpyridine), en cellule photovoltaïque organique en tant qu'additif de la couche active. Cette approche s’avère être particulièrement puissante, permettant notamment de diminuer le temps et le coût énergétique de la mise en œuvre de ces cellules en s’affranchissant d’une étape clé de la fabrication, le recuit
At a time when new technologies emerge every day, a specific domain stands out: the organic electronic. Through its low cost processing or even its utility, the organic electronic constitutes a very promising future.In order to improve the fabrication process and the lifetime of the devices, the work of this thesis was focused on the synthesis of copolymers with various architectures based on poly(3-hexylthiophene) (P3HT). After a first part where main issues and objectives are presented, the synthesis of different P3HT-based precursors is described in a part which could be considered as the heart of these works. Starting with appropriated precursors, the optimization of rod-coil diblock copolymer synthesis was performed following a strategy designed specifically for organic electronic application. Moreover, the precursors were used for the conception of new semi-conducting materials with a variety of architectures, such as graft and star copolymers. Finally, the last part deals with the integration of the P3HT-b-Poly(4-vinylpyridine) copolymer into organic solar cell as an additive of the active layer. This approach turns out to be powerful, especially allowing decreasing the time and the energy cost by avoiding the key step of the fabrication process of those devices, the annealing step
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Ali, Farman. "Models of household behaviour in subsistence agriculture : a case study of NMFP in Pakistan." Thesis, University of East Anglia, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306094.

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Gonçalves, Maria Cecilia. "Estudo experimental da polimerização via radical livre controlada em presença de radicais nitroxido (NMRP)." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266346.

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Orientador: Liliane Maria Ferrareso Lona
Dissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Engenharia Quimica
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Resumo: A polimerização via radical livre controlada mediante radicais nitróxido (NMRP) tem recebido cada vez mais atenção como uma técnica para produção de polímeros com estrutura altamente controlada. Distribuições de pesos moleculares estreitas são obtidas, com polidispersidades baixas. Neste trabalho, será estudado o processo NMRP, no qual ocorre a adição de um radical nitróxido estável, como o 2,2,6,6-tetrametil-l-piperidinoxil (TEMPO) para capturar o radical em crescimento. Embora o processo NMRP de ao polímero características controladas (polidipersidades baixas e pesos moleculares que aumentam linearmente com a conversão), ainda existe um desafio nos processos controlados, por apresentarem baixas velocidades de reação. O objetivo principal deste trabalho está focado num estudo experimental do processo NMRP visando aumentar a velocidade de reação sem perder as características principais do processo. O efeito de dois iniciadores BPO (peróxido de benzoíla) e TBEC (tert-butilperóxido-2-etilhexil carbonato) foi analisado. Observou-se que o TBEC (iniciador com constante de decomposição baixa) foi capaz de aumentar significativamente a taxa de polimerização do processo NMRP, quando comparado ao BPO, pois conversões mais altas foram obtidas, num mesmo tempo de reação, mantendo a característica controlada do sistema. O uso do TBEC apresenta uma vantagem frente ao BPO em processos controlados, não somente porque reduz o tempo de reação, mas também porque concentrações menores de iniciador e controlador foram usadas, obtendo uma taxa de reação ainda maior, o que reduz o custo operacional. Para as condições estudadas, comprovou-se experimentalmente que a taxa de reação é inversamente proporcional à concentração inicial de TEMPO, para uma mesma concentração de iniciador. A análise dos resultados através da aplicação da técnica de planejamento de experimento auxiliou numa melhor compreensão do sistema e na obtenção de condições ótimas de operação para se obter baixas polidispersidades e baixos tempos de polimerização
Abstract: NMRP process (Nitroxide Mediated Radical Polymerization) has received increasing attention as a technique for production polymers with highly controlled structures, narrow molecular weight distribution (MWD) and polydispersity index dose to 1.0. In this work 2,2,6,6-tetramethyl-l-piperidinoxyl (TEMPO) is used as the stable radical to reversibly terminate the growing polymer chain. Polymerizations were performed in ampoules, using TBEC (tert-butylperoxy-2-ethylhexyl carbonate) and BPO (benzoyl peroxide) as initiators. With the purpose of enhancing the reaction rate for NMRP process maintaining the controlled and living characteristics of the polymer synthesized (low polidispersity and molecular weights increasing linearly with conversion) an experimental study was done to evaluate the effect of two different initiators (BPO and TBEC). It was observed that TBEC (initiator with low decomposition rate) was able to enhance significant1y the polymerization rate compared to BPO, keeping the living and controlled characteristics of the system. The results show that TBEC seems to be a promising initiator that make the NMRP process more efficient, not only because it reduces the polymerization time, but also because it allows smaller amounts of controller and initiator to be used. For the operational conditions studied, experimental results with TBEC exposed that the polymerization rate in inversely proportional to the initial concentration of TEMPO, for the same amount of initiator. Using a statistical planning, it was possible to obtain a better understanding of the system and to search for operating conditions that bring low polydispersity and low reaction rates. Finally, the results are expected to have significant benefits for controlled polymerization on an industrial setting
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
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22

Huda, Sfeir. "Ingénierie macromoléculaire pour la synthèse de particules de latex par polymérisation en miniémulsion." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3002/document.

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Au cours de ce travail de thèse, nous avons étudié la synthèse de particules de latex par polymérisation en miniémulsion, un procédé de polymérisation en milieu aqueux dispersé. Nous avons synthétisé avec succès et de manière contrôlée des particules de latex de polystyrène de masse molaire élevée (Mn > 30 000 g.mol-1) par polymérisation radicalaire contrôlée par les nitroxydes (NMP) en miniémulsion, en présence et en absence de tensio-actif moléculaire. Des latex stables présentant des diamètres de l’ordre de 150 – 200 nm ont été synthétisés. Une seconde partie de ce travail de thèse est dédié à la transposition de la polymérisation radicalaire contrôlée par les nitroxydes amorcée depuis la surface (« surface-initiated NMP ») d’un procédé en masse vers un procédé en milieu aqueux dispersé (miniémulsion) en vue de synthétiser des nanoparticules cœur@écorce de type silica@polystyrène. La dernière partie du travail de thèse est consacrée à la synthèse de stabilisants polymères et plus précisément à la synthèse de copolymères amphiphiles à base de dextrane ou de poly(acide acrylique) modifiés de manière hydrophobes par des terpènes. L’efficacité de stabilisation de tels copolymères synthétisés à partir de bio-resources a été étudiée au travers leur capacité à stabiliser la polymérisation en miniémulsion du styrène. Tout au long de ce travail, les caractéristiques macromoléculaires des polymères ainsi que la taille et la morphologie des particules ont été caractérisées respectivement par chromatographie d’exclusion stérique, diffusion dynamique de la lumière et microscopie (SEM, TEM, AFM)
During the work of this PhD, we investigated the synthesis of latex particles by miniemulsion, an aqueous dispersed medium process. We managed to synthesize in a controlled manner high molar mass (Mn > 30 000 g.mol-1) polystyrene latex particles via nitroxide mediated radical polymerization (NMP) in miniemulsion in both the presence and absence of molecular surfactant. Stable latex with final diameters within the range of 150-200 nm were synthesized. A second part of the PhD work was devoted to the transposition of surface-initiated NMP from bulk polymerization to polymerization in aqueous dispersed media (miniemulsion) in order to synthesize silica@polystyrene core@shell hybrid nanoparticles. The last part of the PhD work was dedicated to the synthesis of polymeric stabilizers, more precisely to the synthesis of amphiphilic copolymers based on dextran or poly(acrylic acid) polymers hydrophobically modified by terpenes. The stabilization efficiency of such copolymers synthesized from renewable resources to stabilize styrene miniemulsion polymerization was investigated. During this work, we characterized the macromolecular features of polymers along with the size and the morphology of the final particles by respectively size exclusion chromatography (SEC), dynamic light scattering (DLS) and microscopy (SEM, TEM, AFM)
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23

Augusto, Dora Susana Castro Rodrigues. "Teores de vibrios halófilos patogénicos humanos em ostras, por NMP-PCR." Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/737.

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Mestrado em Microbiologia
O presente estudo foi levado a cabo com o objectivo de determinar a ocorrência e os níveis de Vibrio vulnificus, Vibrio parahaemolyticus (total e potencialmente patogénico) em ostras naturalmente contaminadas, usando dois métodos diferentes de Número Mais Provável (NMP) em conjugação com a técnica de reacção em cadeia da polimerase (PCR) de modo a seleccionar o mais apropriado para análise de rotina. As ostras foram adquiridas em lojas e supermercados locais. Os valores de V. vulnificus (portador do gene que codifica a hemolisina/citolisina da bactéria - vvhA), V. parahaemolyticus total (portador do gene específico da espécie – toxR) e V. parahaemolyticus potencialmente patogénico (portador dos genes que codificam as hemolisinas directa termoestável – tdh e directa termoestável relacionada – trh) foram determinados usando dois métodos de NMP-PCR: (1) enriquecimento em água peptonada alcalina (APW) seguido de PCR (APW-PCR); e (2) enriquecimento em APW e isolamento em agar de tiossulfato citrato bílis sacarose (TCBS) seguido de confirmação das estirpes por PCR (TCBS-PCR). Foi detectado V. vulnificus em quatro amostras de ostras pelo método APWPCR e em três amostras pelo método TCBS-PCR, mas nunca nas mesmas amostras. Foi possível encontrar V. parahaemolyticus em 14 amostras pelo método APW-PCR e em 13 amostras pelo método TCBS-PCR. Quanto aos factores de virulência, foi possível detectar o gene tdh em uma amostra somente pelo método APW-PCR; o gene trh foi detectado em cinco amostras por ambos os métodos, mas nem sempre na mesma amostra. O método APW-PCR demonstrou ser o mais adequado para detectar a presença de V. parahaemolyticus total em ostras, uma vez que gerou maior número de amostras positivas e detectou teores mais elevados, no entanto, recomenda-se o recurso a ambos os métodos para a detecção dos factores de virulência do V. parahaemolyticus e para a detecção de V. vulnificus. ABSTRACT: The present study was carried out to determine the occurrence and levels of Vibrio vulnificus and total and potentially pathogenic Vibrio parahaemolyticus bacteria in naturally contaminated oysters, using two Most Probable Number – Polymerase Chain Reaction (MPN-PCR) different methods in order to select the most appropriate for routine analysis. Oysters were collected from local stores and supermarkets. V. vulnificus (carrying the hemolysin/ cytolysin vvhA gene), total V. parahaemolyticus (carrying the species-specific toxR gene) and potentially pathogenic (carrying the thermostable direct hemolysin - tdh and TDH-related hemolysin - trh genes) V. parahaemolyticus were enumerated by two MPN-PCR methods: (1) Alkaline Peptone Water (APW) enrichment followed by PCR (APW-PCR); and (2) APW enrichment plus isolation on Thiosulfate Citrate Bile Sucrose (TCBS) agar followed by PCR strain confirmation (TCBS-PCR). V. vulnificus was found in four oyster samples by the APW-PCR method and in three by the TCBS-PCR method, but never in the same samples. V. parahaemolyticus was found in 14 oyster samples by the APW-PCR method and in 13 by the TCBS-PCR method. Concerning virulence factors, tdh positive organisms were only detected by the APW-PCR method in one sample; trh positive organisms were found in five oyster samples by both methods though not always in the same sample. The APW-PCR method has shown to be more adequate for the detection of total V. parahaemolyticus in oysters, since it yielded a larger number of positive samples, however, for detection of V. parahaemolyticus virulence factors and V. vulnificus, both methods should be used.
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24

Stier, Katja [Verfasser]. "TATI und NMP 22 als Tumormarker des oberflächlichen Harnblasenkarzinoms / Katja Stier." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2011. http://d-nb.info/1025354877/34.

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25

Fleischmann, Sven. "Alkinhaltige Blockcopolymere und ihre Modifizierung mittels 1,3-dipolarer Cycloaddition." Doctoral thesis, München Verl. Dr. Hut, 2008. http://d-nb.info/991285212/04.

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26

Napp, Christiane. "Charakterisierung des humanen Gens nma ein neuer Antagonist der Wirkung des BMP4 /." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970950586.

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27

Obhof, Theresa [Verfasser], and J. [Akademischer Betreuer] Kämper. "Charakterisierung der zytoplasmatischen Funktion von Num1 und Nma1 in Ustilago maydis / Theresa Obhof ; Betreuer: J. Kämper." Karlsruhe : KIT-Bibliothek, 2017. http://d-nb.info/1137264896/34.

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28

Nogueira, Telma Regina. "Investigação experimental da copolimerização de estireno divinilbenzeno (DVB) via radical livre controlada por radicais nitroxido (NMRP)." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267631.

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Orientador: Liliane Maria Ferrareso Lona
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Polimerização via radical livre controlada, também conhecida como "pseudoliving radical polymerization" tem recebido cada vez mais atenção como uma técnica para produção de polímeros com micro estrutura altamente controlada. Em particular, distribuições de pesos moleculares estreitas são obtidas, com polidispersidade muito próxima de um. Rotas convencionais para polímeros como estes têm sido polimerizações iônicas, no entanto, elas são extremamente sensíveis a impurezas e ao tipo de solvente. Processos de polimerização via radical livre, que são muito mais versáteis e robustos a impurezas, para a produção de polímeros com estruturas controladas via processo "controlado" ou "pseudo-living", têm se tornado uma importante alternativa. Como desvantagem do processo controlado aponta-se a baixa velocidade de reação quando comparada à polimerização convencional. A maioria dos trabalhos publicados sobre polimerização controlada via radicais nitróxido é feita considerando o estudo da homopolimerização de estireno. Neste projeto de pesquisa, é investigada, em nível experimental, a co-polimerização de estireno e divinilbenzeno (DVB) via polimerização controlada por nitróxidos (NMRP) usando 2,2,6,6- tetrametil-1-piperidinoxil (TEMPO) como controlador e tert-butilperóxido-2-etilhexil carbonato (TBEC) como iniciador. O DVB funciona como gerador de ramificações na cadeia polimérica, melhorando as propriedades do estireno como resistência a solvente e ao impacto. O TBEC foi utilizado em substituição a iniciadores mais convencionais como o 2,2-azo-bis-iso-butironitrila (AIBN) e peróxido de benzoíla (BPO), com o objetivo de acelerar a velocidade de reação, tentando manter o sistema controlado. Todos os experimentos foram feitos em ampolas. Para um melhor entendimento deste sistema, muitos experimentos foram realizados a diferentes temperaturas, concentrações de divinilbenzeno, concentrações de iniciador e razões molares entre as concentrações de controlador e iniciador. A conversão do monômero foi obtida por gravimetria e o polímero foi caracterizado através de Cromatografia de Permeação em Gel (GPC). Foi demonstrado que o TBEC foi capaz de aumentar a velocidade de reação em relação ao BPO e, em algumas condições operacionais utilizadas, polidispersidades próximas da unidade foram obtidas.
Abstract: Living free radical polymerization, also known as "pseudo-living radical polymerization" has received more and more attention as a technique for the production of polymers with micro structure highly controlled (narrow molecular weights distributions and polydispersity index close to one). Conventional routes to obtain polymer like this have been ionic polymerizations, however, they are extremely sensitive to impurities and solvents. Free radical polymerizations, which are more versatile and robust to impurities, for the production of polymers with controlled structures by "controlled" or "pseudo-living" process, have become an important alternative. As a disadvantage of the controlled process can be pointed the low reaction rate when compared to the conventional process. Most of the published papers about nitroxide mediated living free radical polymerization consider the homopolymerization of styrene as case study. In this research, the co-polymerization of styrene and divinylbenzene (DVB) by living free radical polymerization (NMRP) is investigated in experimental level. The stable radical used was 2,2,6,6-tetramethyl-1-piperidinoxyl (TEMPO). The initiators used in this work were tertbutylperoxy- 2-ethylhexyl carbonate (TBEC) and benzoyl peroxide (BPO). DVB acts as a branching generator, improving the properties of the styrene as the solvent and impact resistance. TBEC was used in substitution to conventional initiators as 2, 2-Azo-bisisobutyronitrile (AIBN) and BPO, with the aim of accelerating the reaction rate, trying to keep a controlled/living system. All the experiments were performed in ampoules. To better understand this system, many experiments were performed at different temperatures, divinylbenzene concentrations, initiator concentrations and molar ratios between controller and initiator. Conversion was obtained by gravimetric method and the polymer was characterized by Gel Permeation Chromatograph (GPC). It was observed that, at certain operating conditions, the TBEC initiator was able to produce copolymers with polydispersity close to unity in a much faster velocity when compared to BPO.
Mestrado
Processos Quimicos
Mestre em Engenharia Química
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29

Sieczkowska, Barbara. "Functional polymer layers with protected amines." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244668077080-12212.

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This work refers to the area of bio-nanotechnology and concerns the selective immobilization of DNA or other bio-template on microstructured gold contacts and which then permit a coordinated cooperation of several of these nanotemplate, e.g., within a microreactor. The immobilization of such nano-objects should be realized through functional thin polymer films which provide binding groups. Thus, the main aim of this work was the development of polymeric materials for thin functional films which permit to deposit on different substrates a wide variation of functional elements or metal structures and to achieve a pattern formation using optical grid methods. In order to realize this concept it was necessary to design and develop a polymer system based on suitable photolabile units and in addition having anchoring groups which attach on specific substrates like gold. In this terpolymer concept was aimed for which consists of three components with particular functions in suitable molar ratios, which allow the tune the properties of the materials, and provide: amino photolabile protected groups for the photolithographic creation of patterned areas with free amino groups, which are available for further modifications like attachment of colloids, metallization or attachment of DNA strands; disulfide derivative anchor groups providing anchoring capacity for gold surface and spacer groups for adjusting the film quality. These multifunctional terpolymers should be synthesised by free radical polymerisation of suitable monomers. Although these techniques are successful, they are limited by their complexity, rigorous synthetic demands, as well as incompatibility with many functional termolabile and highly reactive functionalities. To overcome these difficulties a polymerisation technique based on “living” free radical polymerisation has been used in this work. A highly efficient polymer-analogous modification allows to introduce the functionalities after the polymer construction reaction. The production of suitable prepolymers [poly(styrene-r-4-propargyl-oxystyrene)] was carried out with the help of a controlled synthesis methodology “nitroxide mediate radical polymerization" followed by polymer analogous reaction using one of the most efficient click reactions, the Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition between terminal acetylenes and azides to attach further functionalities through the formation of a stable 1,4-disubstituted 1,2,3-triazol ring . The combination of nitroxide mediated radical polymerization (NMRP) and click chemistry was used to produce well-defined random copolymer. It could already be shown that also block copolymers can be prepared which give the chance to combine nanostructure formation in block copolymers with special functionality. Thus, the special properties of these functional polymers like the capability for photopatterning and anchoring onto gold substrates make them very interesting for nanotechnology applications
Diese Arbeit bezieht sich auf das Gebiet der Bionanotechnologie und betrifft ein neuartiges Verfahren zur selektiven Immobilisierung der DNA oder anderer Biomoleküle auf mikrostrukturierten Goldkontakten, welche dann ein koordiniertes Zusammenwirken von einzelnen Nanomolekülen ermöglichen, z.B. in einem Mikroreaktor. Die Immobilisierung solcher Nanoobjekte soll durch dünne Funktionsschichten realisiert werden, die die Anbindungsgruppen liefern. Folglich war das Hauptziel dieser Arbeit die Entwicklung von Polymermaterialien für dünne Funktionsschichten, die die Aufbringung einer großen Vielzahl von Funktionselementen oder metallischen Strukturen auf verschiedenen Substraten gestatten und die Strukturierung durch den Einsatz von lithographischen Methoden ermöglichen. Um dieses Konzept zu realisieren, war es notwendig, ein Polymersystem zu gestalten und zu entwickeln, welches auf geeignete photolabile Einheiten basiert und zusätzlich Ankergruppen hat, die mit spezifischen Substraten wie Gold verbunden ist. Dieses Terpolymerkonzept wurde gezielt aus drei Komponenten mit speziellen Funktionen in entsprechenden molaren Verhältnissen gebildet, die eine Abstimmung der Materialeigenschaften ermöglicht und folgendes bereitstellt: photolabile geschützte Aminogruppen für die photolitographische Strukturerzeugung mit freien Aminogruppen, welche für weitere Modifikationen verfügbar sind wie das Anhängen von Kolloiden, die Metallisierung oder Anfügung von DNA-Strängen; disulfide Derivate für die kovalente Anbindung auf der Goldoberfläche und Spacer-Gruppe für Verbesserung der Schichtenbildung. Diese multifunktionalen Terpolymere sollen durch eine freie radikalische Polymerisation von entsprechenden Monomeren synthetisiert werden. Obwohl diese Techniken erfolgreich sind, sind sie eingeschränkt durch ihre Komplexität, den strengen synthetischen Anforderungen, sowie der Inkompatibilität mit vielen funktionalen thermolabilen und hochreaktiven Funktionalitäten. Um diese Schwierigkeiten zu überwinden wurde eine Polymerisationstechnik für diese Arbeit genutzt, die auf der „lebenden“ freien radikalischen Polymerisation basiert. Eine hoch effiziente polymeranaloge Modifizierung erlaubt die Einführung von Funktionalitäten nach der Polymeraufbaureaktion. Die Herstellung von entsprechenden Präpolymeren Poly(Styrol-r-4-Propargyl-oxystyrol) wurde mittels einer kontrollierten Synthesemethodik „Nitroxid-mediated controled radical polymerisation“ (NMRP) durchgeführt, gefolgt von der Polymeranalogreaktion, die eine der effizientesten Click-Reaktion - die Cu(I) katalysierte 1,3-dipolar Cycloaddition von terminalen Alkinen an Aziden nach Huisgen nutzt, um weiter Funktionalitäten durch die Bildung eines stabilen 1,4-disubstituierten-[1,2,3]-Triazolringes anzufügen. Die Kombination von NMRP und Click-Chemie wurde zur Herstellung eines exakt definierten Random Copolymers genutzt. Es konnte bereits gezeigt werden, dass auch Blockcopolymere geschaffen werden können, die eine Möglichkeit zur Kombination von Nanostrukturformationen in Blockcopolymeren mit speziellen Funktionaltäten bieten. Folglich sind die speziellen Eigenschaften dieser Funktionalpolymere wie die Fähigkeit zur Photostrukturierung und Verankerung auf Goldsubstraten für nanotechnologische Anwendungen sehr interessant
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30

Thiessen, Wladimir. "Polymere und Nanopartikel - Verfahren für die Chemische Nanotechnologie." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-65374.

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In der vorliegenden Arbeit soll das weit gefächerte Thema der chemischen Nanotechnologie um neue Resultate bereichert werden. Im Einzelnen handelt es sich um neue Synthesemethoden für magnetische Nanorods (Nanoteilchen mit länglicher Form) und Nanoshells (oxidische Nanokristalle mit einer Hülle aus Edelmetall), ein Verfahren zur Modifizierung diverser Oberflächen mit heterogenen Polymerbürsten durch kontrollierte binäre radikalische Polymerisation, neuartige Copolymere zur Stabilisierung und Funktionalisierung von Nanopartikeln und Herstellung von amphiphilen Nanopartikeln durch Oberflächenbehandlung mit Niotensiden. Es sollen ferner die möglichen Anwendungen diskutiert werden. Die Abb. 1 illustriert die Zusammenhänge der bearbeiteten Thematik.
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31

Galhardo, Eduardo 1982. "Viabilização da polimerização mediada por nitróxidos (NMRP) em emulsão por meio da variação de parâmetros de processos." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266601.

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Orientador: Liliane Maria Ferrareso Lona
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: A polimerização via radical livre controlada, também conhecida como "Living Free Radical Polymerization" (LFRP) tem recebido cada vez mais atenção como uma técnica para produção de polímeros com cadeias monodispersas. Em particular, distribuições de massas moleculares estreitas são obtidas, com polidispersidade muito próxima de um. Rotas convencionais para polimerizações como esta têm sido as iônicas, no entanto, elas são extremamente sensíveis a impurezas e tipo de solvente. Desta forma, processos de polimerização via radical livre, que são muito mais versáteis e robustos a impurezas, para a produção de polímeros com estruturas controladas via processo "controlado", tem se tornado uma importante alternativa. Neste projeto de pesquisa, foi feito um estudo em nível experimental para investigar a polimerização controlada mediada por nitróxidos (NMRP, do inglês, Nitroxide Mediate Radical Polymerization), utilizando-se a polimerização em emulsão. Esse tipo de polimerização apresenta alta versatilidade industrial e também um ganho ambiental, já que um solvente orgânico é, nesse caso, substituído por água. Um dos desafios enfrentados em processar a polimerização NMRP em emulsão foi à manutenção da água em seu estado líquido, já que o processo NMRP, utilizando-se TEMPO (2, 2, 6,6-tetrametil-1-piperidinoxil) como controlador, somente se dá a uma temperatura maior que 100ºC, o que exigiu a pressurização do sistema. As quantidades de surfactante (SDS) foram alteradas de forma sistemática: 5,00 7,50 e 10,00 g. Percebeu-se que, usando 5,00g de SDS, menores polidispersidades e massas moleculares foram alcançadas, o que prova uma relação entre esses parâmetros e o número de partículas nucleadas. A relação monômero/água (v/v) também foi alterada, a saber: 0,33, 0,55, 0,70 e 0,75. Percebeu-se que a relação 0,75 forneceu as menores polidispersidades e as maiores massas moleculares. Um estudo teórico realizado com o Software Gaussian 3.0 mostrou os valores da entalpia para a espécie alquociamina dormente e para a reação global
Abstract: Controlled radicalar polymerization, known also by Living Free Radical Polymerization, has received every time more attention as being a technique for production of polymer with highly controlled microstructure. Particularly, narrow molecular weight distributions are reached, with polydispersity very close to one. Conventional routes for polymerizations like this has been the ionic, however, it is extremely sensitive to impurities and kind of solvent. This way, processes of polymerization via free radical, which are much more versatile and robust to impurities for the polymer production with controlled structures via "controlled process", has been an important alternative. In this work Nitroxide Mediated Radical Polymerization (NMRP) using TEMPO (2,2,6,6-tetrametyl-1-piperidinoxyl) as controller and emulsion polymerization was investigated. Conventional emulsion polymerization presents high industrial versatility, due to range of monomers that can be applied, and also an environmentally advantage, because an organic solvent is replaced by water. One of the challenges faced was keeping the water in liquid physical state, because the maximum efficiency of the process occurs at a temperature higher than 115ºC, what demanded the pressurization of the system. The quantities of surfactant (SDS) were systematically changed: 5.00, 7.50 and 10.00 g, respectively. It was perceived that using 5.00 g of SDS, lower values of polydispersity and molecular weight were obtained, what ensures a relation between such parameters and the number of nucleated particles. The relation monomer/water (v/v) was also changed, namely: 0.33, 0.55, 0.70 and 0.75. It was noticed that the relation 0.75 provided the lowest polydispersities and the highest molecular weights. The theoretical study performed with the Software Gaussian 3.0 showed the enthalpy values for the dormant alkoxyamine specie and for the global reaction
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
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32

Marchiani, Mariana. "Estudo do perfil genético de pacientes com Neoplasias Mieloproliferativas (NMP) cromossomo Filadélfia negativo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5167/tde-02052016-124952/.

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As neoplasias mieloproliferativas (NMPs) Filadelfia negativo como a policitemia vera (PV), trombocitemia essencial (TE) e mielofibrose primária (MFP) são desordens clonais da célula tronco hematopoiética caracterizadas pela produção excessiva de células mielóides diferenciadas. Este fenômeno ocorre devido à uma mutação somática (JAK2V617F) que ativa a via JAK-STAT de transdução de forma constitutiva. Esta mutação é mais frequente na PV, ocorrendo em 95% dos casos, e em 50% dos casos de TE e MFP. Outro defeito genético que ocorre é a mutação no receptor de trombopoetina, MPL. As mutações em MPL podem ser germinativas ou somáticas e menos de 10% dos pacientes com TE e MFP apresentam essa alteração genética. Entretanto, grande parte dos pacientes com TE e MFP que não apresentam mutação em JAK2V617F ou MPL podem apresentar mutações somáticas no gene CALR. Em adição às mutações somáticas que causam mieloproliferação, outras alterações genéticas em genes que funcionam como reguladores epigenéticos são encontrados nas NMPs nos genes TET2, IDH1, IDH2 e ASLX1. Objetivo: Estabelecer um perfil genético em pacientes com NMP através da avaliação de mutações nos genes JAK2, CALR, MPL, IDH1, IDH2, TET2 e ASXL1 assim como estabelecer uma correlação laboratorial destas na PV, TE e MFP. Casuística e Métodos: Foram utilizadas amostras de sangue periférico de 104 pacientes que foram enviadas para o Laboratório de Biologia Tumoral do Serviço de Hematologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo para avaliação diagnóstica. Quinze dos 104 pacientes são de pacientes com PV (14,4%), 20/104 (19,2%) com MFP, 20/104 (19,2%) com TE e 49/104 (47,1%) com outras doenças hemtológicas. Foi feita a avaliação da prevalência de mutações somáticas, seja por sequenciamento ou análise de fragmentos, nos genes JAK2 (exon 12 e Y931C), MPL, IDH1, IDH2, CALR, TET2 e ASXL1. PCR-RFLP foi realizada para identificação de mutações em JAK2V617F. Resultados: A mutação JAK2V617F foi observada em 30 (28,8%) pacientes (12 PV, 11 TE e 7 MFP), a mutação JAK2 exon 12 foi observada em apenas um (0,96%) paciente com PV, mutação JAK2Y931C em 4 (3,8%) pacientes (1 PV, 2 TE e 1 MFP) e 8 (7,7%) pacientes apresentaram mutações em CALR (3 TE e 5 MFP). Mutações nos genes epigenéticos como IDH1 foram observadas em 9 (8,7%) pacientes (2 TE, 2 MFP, 1 SMD, e 4 pacientes com suspeita de NMP), mutações em IDH2 estão presentes em 5 (4,8%) pacientes (2 TE, 1 SMD/leucemia e 4 pacientes com suspeita de NMP), mutações em ASXL1 foram identificadas em 13 (12,5%) pacientes (1 PV, 3 TE, 2 MFP, 3 SMD/leucemias e 4 com suspeita de NMP) e finalmente, mutações em TET2 foram encontradas em 33 (31,7%) pacientes (3 PV, 5 TE, 4 MFP, 8 SMD/leucemias e 13 pacientes com suspeita de NMP). Além disso, no caso da PV, os pacientes que apresentam mutações em JAK2V617F apresentam valores aumentados de plaquetas (mediana de 5,41 x 105/mm3 plaquetas) em relação aos pacientes sem a mutação (mediana de 2,06 x 105/mm3 plaquetas), com diferença estatística (p=0,031). Pacientes do mesmo grupo que apresentam mutações em TET2 apresentam, opostamente aos com mutações em JAK2V617F, menores valores de plaquetas (mediana de 1,75 x105/mm3 plaquetas) em relação aos pacientes sem mutações no gene TET2 (mediana de 5,41 x 105/mm3 plaquetas), com diferença estatística (p=0,048). No caso da MFP, os pacientes que apresentam mutações em JAK2V617F apresentam valores maiores de leucócitos (mediana de 1,09 x104/mm3 leucócitos) do que os pacientes que não apresentam a mutação (mediana de 6,99 x103/mm3 leucócitos) com diferença estatística (p=0,046), já os pacientes que apresentam mutações no gene ASXL1 apresentam valores menores de hemácias (mediana de 2,43 x106/mm3 hemácias) em relação aos pacientes que não apresentam mutação (mediana de 3,71 x106/mm3 hemácias) com diferença estatística (p=0,042). Conclusão: O trabalho permitiu fornecer um perfil genético dos pacientes com NMP estudados. Além disso, é possível observar que algumas mutações epigenéticas podem influenciar em diferenças clínicas
Myeloproliferative neoplasms (MPNs) Philadelphia (Ph) chromosome negative, such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are clonal disorders of hematopoietic stem cell characterized by increased proliferation of differentiated myeloid cells. This phenomenon occurs due somatic mutation (JAK2V617F) that constitutively stimulates the JAK-STAT signaling pathway. This mutation is more frequent in PV, around 95%, and between 50% in ET and PMF. Other genetic aberration can be observed in the thrombopoietin (TPO) receptor MPL. Mutations in MPL can be in the germline line or somatic and less than 10% of patients with TE or PMF would harbor this genetic alteration. Otherwise, patients with TE or PMF without JAK2V617F or MPL mutation could present somatic mutations in calreticulin (CALR). In addition to somatic mutations that cause myeloproliferation, other genetic alterations that function as epigenetic regulators were identified in genes as TET2, IDH1, IDH2 e ASLX1 in MPN. Objective: Establish genetic profile in patients with diagnosis of PV, ET, and PMF through genetic alterations in the following genes: JAK2, MPL, CALR, IDH1, IDH2, TET2 e ASXL1, and correlate those alterations with demographic characteristic of the study population. Casuistic and Methods: Peripheral blood samples from 104 patients referred to the Tumor Biology Laboratory of the Department of Hematology of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo for diagnostic investigation were analyzed. Fifteen out 104 samples were from PV patients (14.4%), 20/104 (19.2%) in PMF, 20/104 (19.2%) in ET and 49/104 (47.1%) with other hematologic diseases. Identification of somatic mutations was made, either by direct sequencing or fragment analysis in JAK2 (exon 12 and Y931C), MPL, IDH1, IDH2, CALR, TET2 and ASXL1. PCR-RFLP was performed to identify JAK2V617F mutation. Results: JAK2V617F mutation was observed in 30 (28.8%) patients (12 PV, 11 ET and 7 PMF), JAK2 exon 12 in only one (0.96%) patient with PV, JAK2Y931C in 4 (3.8%) patients (1 PV, 2 ET and 1 PMF), and 8 patients (7.7%) presented CALR mutation (3 ET and 5 PMF). Mutations in the epigenetic genes as IDH1 were observed in 9 (8.7%) patients (2 ET, 2 PMF, 1 MDS and 4 patients with suspected MPN), IDH2 mutations were present in 5 (4.8%) patients (2 ET, 1 MDS/leukemia, and 4 patients with suspected MPN), ASLX1 mutations were identified in 13 (12.5%) patients (1 PV, 3 ET, 2 PMF, 3 MDS/leukemia and 4 with suspected MPN) and finally, TET2 mutations were present in 33 (31.7%) patients (3 PV, 5 ET, 4 PMF, 8 MDS/leukemia, and 13 with suspected MPN). In addition, patients with PV who harbor JAK2V617F have increased platelet counts (median 5.41 x 105/mm3 platelets) compared to those without the mutation (median 2.06 x 105/mm3 platelets, p=0.031). Patients in the same group with TET2 mutation, as opposed to those with JAK2V617F, presented low platelets counts (median of 1.75 x 105/mm3 platelets) compared to those without TET2 mutation (median 5.41 x 105/mm3 platelets, p=0.048). Presence of JAK2V617F in patients diagnosed with PMF have a greater number of leukocytes (median 1.09 x104/mm3 leukocytes) when compared to patients without the mutation (median 6.99 x 103/mm3 leukocytes, p=0.046). Patients with PMF who presented mutations in ASXL1 gene have a lower number of red blood cells (median of 2.43 x 106/mm3) compared to patients without mutations in the same gene (median 3.71 x 106/mm3, p=0.042). Conclusion: The present study allows us to provide a genetic profile of patients with MPN. Furthermore, it is possible to observe that some epigenetic mutations could influence in some clinical differences
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33

Simms, Ryan W. "Living/controlled Polymerization Conducted in Aqueous Based Systems." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/700.

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Carvalho, Verônica Vale. "Caracterização química das frações de N-metil-pirrolidona de asfaltenos por espectrometria de massas de Ressonância Ciclotrônica de Íons com Transformada de Fourier." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/5835.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Heavy oil fractions studies are of great importance for the oil industry, receiving special attention in recent decades due to the interest to meet them in order to obtain compounds with higher added value derived from this. Moreover, these studies also aim solutions to the problems caused by these fractions during all processing steps oil. Asphaltenes in NMP produces two fractions, a soluble and the other insoluble in NMP. It was suggested that the NI fraction present low content of aromatic compounds, opening a new debate on the composition of asphaltenes which are widely discussed in the literature as aromatic and polar compounds. In the present work is the chemical study of these asphaltenes fractions by mass spectrometry of high resolution mass and accuracy, making use of the resonance cyclotron Ion Fourier Transform (FT-ICR MS) associated with the source of atmospheric pressure ionization - ESI (electrospray ionization), infrared, fluorescence and 1H NMR. The infrared analysis, 1H NMR and Fluorescence made it possible to observe differences among samples, where NS fraction had higher amounts of heteroatoms present and a higher percentage of aromatic hydrogens and NI fraction is nonpolar in the presence of increasing amounts of alkyl and naphthenic hydrocarbons. The results of FT-ICR MS corroborated with the other results, showing that the NS fractions showed high proportion of heteroatomics species and higher DBE values compared NI fractions exhibited predominantly hydrocarbon compounds and derisory amounts of heteroatoms and also insignificant quantities compounds of DBE values different from zero.
Os estudos das frações pesadas do petróleo são de grande importância para a indústria petrolífera, recebendo atenção especial nas últimas décadas devido ao interesse em conhecê-las visando a obtenção de compostos com maior valor agregado oriundos desta. Por outro lado, estes estudos também objetivam soluções para os problemas causados por essas frações durante todas as etapas de processamento do petróleo. Os asfaltenos em NMP produzem duas frações, uma solúvel e outra insolúvel em NMP. Foi sugerido que a fração NI apresente baixo teor de compostos aromáticos, abrindo um novo debate sobre a composição dos asfaltenos que são largamente discutidos na literatura como compostos aromáticos e polares. No presente trabalho realizou-se o estudo químico destas frações de asfaltenos por espectrometria de massas de altíssima resolução e exatidão, fazendo uso da Ressonância Ciclotrônica de Íons com Transformada de Fourier, (FT-ICR MS) associada com a fonte de ionização a pressão atmosférica – ESI (ionização por electrospray), infravermelho, fluorescência e RMN de 1H. As análises de infravermelho, RMN de 1H e fluorescência, possibilitaram observar as diferenças existentes entre as amostras, onde a fração NS apresentou maiores quantidades de heteroátomos presentes e maior porcentagem de hidrogênios aromáticos e a fração NI se mostrou apolar com a presença de maiores quantidades de hidrocarbonetos alquílicos e naftênicos. Os resultados de FT-ICR MS corroboraram com os demais resultados, evidenciando que, as frações NS apresentaram elevada proporção de espécies heteroatômicas e maiores valores de DBE quando comparadas as frações NI que exibiram predominância de compostos hidrocarbonetos e quantidades irrisórias de heteroátomos e também quantidades insignificantes de compostos com valores de DBE diferentes de zero.
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35

Dias, Rafael Silva. "Investigação experimental e computacional da polimerização via radical livre controlada em presença de radicais nitroxido (NMRP) utilizando-se iniciadores difuncionais." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266460.

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Orientador: Liliane Maria Ferrareso Lona
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Polimerização via radical livre controlada, ou Living Free Radical Polymerization (LFRP) tem recebido cada vez mais atenção como uma técnica para produção de polímeros com micro estrutura altamente controlada. Em particular, distribuições de pesos moleculares estreitas são obtidas, com polidispersidade próxima de um. Rotas usuais para obtenção de polímeros como estes têm sido polimerizações iônicas, mas elas são extremamente sensíveis a impurezas. Dentre os processos controlados, a polimerização mediada por nitróxidos (Nitroxide-Mediated Radical Polymerization-NMRP) permite a introdução de funcionalidades químicas na cadeia polimérica e apresenta como vantagens a possibilidade de polimerizações em meio aquoso, síntese de materiais híbridos, copolímeros, além de ser a rota química com menor impacto no meio-ambiente. Contudo, um dos desafios a ser enfrentado na LFRP, inclusive na NMRP, é o aumento da velocidade de reação, uma vez que as polimerizações controladas são muito mais lentas em função da existência de uma etapa de equilíbrio intrínseca. Na busca de maiores produtividades, utilizam-se temperaturas de operação ou concentração de iniciadores monofuncionais elevadas que, por conseqüência, geram polímeros com pesos moleculares mais baixos. Nos processos de polimerização convencional, o uso de iniciadores difuncionais permite o aumento da produtividade sem alterações ou mesmo com um aumento dos pesos moleculares. Sendo assim, nesta tese, foi feito um estudo experimental (polimerização em ampolas) e de simulação (desenvolvimento de modelos determinísticos e empíricos) para investigar a NMRP, no sentido de tentar reduzir o tempo gasto na polimerização, através do uso de iniciadores difuncionais. Particularmente, foram avaliadas as massas moleculares e a polidispersidade do poliestireno sintetizado usando o TEMPO (2,2,6,6, tetrametil-1-piperidinoxil) como controlador através de uma comparação com iniciadores monofuncionais (BPO e TBEC). Através de um planejamento de experimentos, determinou-se a influência da concentração do iniciador difuncional L531, da razão controlador/iniciador, e da temperatura na conversão, nos pesos moleculares e na polidispersidade e chegou-se a um modelo empírico. Foi proposto um mecanismo de reação com a derivação de equações de balanço de massa e de momentos para um reator batelada. Fez-se um bom ajuste do modelo com a estimativa de alguns parâmetros. Finalmente, desenvolveu-se uma análise de sensibilidade (dinâmica) dos parâmetros do modelo. Ambos os resultados experimentais e de simulação mostraram que foi possível obter um aumento na conversão aliado a um incremento nas massas moleculares ao se usar o iniciador difuncional L531 em relação ao monofuncionais, sendo mantido o processo controlado. Esta abordagem é inédita, pois não foi encontrado na literatura aberta nenhum tipo de polimerização radicalar controlada por nitróxidos que faça uso de iniciadores com funcionalidade superior a um.
Abstract: Controlled/Living Free Radical Polymerization (LFRP) is one of the most important techniques for production of polymeric materials with good control of the microstructure (e.g., narrow molecular weight distributions). Such properties can also be achieved via ionic polymerizations, but being a free radical polymerization process, LFRP is much less sensitive to impurities and solvents. The Nitroxide-Mediated Radical Polymerization (NMRP), as well as other LFRP processes, provides end functional polymers, and recently it has shown advantages related to polymerization in aqueous media, synthesis of hybrid materials, block copolymers, and environmental issues. However, one challenge that still must be overcome in LFRP, as well as in NMRP process, is to increase slow polymerization rates experienced due to the establishment of an intrinsic equilibrium. In order to achieve higher productivities, higher reaction temperatures or higher (monofunctional) initiator concentrations are usually used, but as a result, polymers with lower molecular weight are produced. It is well known that the use of di-functional initiators provides an enhancement of the reaction rate of conventional free radical polymerization with either no change or even an increase in molecular weight averages. Therefore, in this thesis, it was taken an experimental (polymerization in ampoules) and computational (deterministic and empirical methods) investigation of the effect of di-functional initiators on nitroxide-mediated radical polymerization with the purpose of enhancing the reaction rate. Particularly, the molecular weight development (number average molecular weight and polydispersity) of polystyrene synthesized by using TEMPO (2,2,6,6-tetramethyl-1-piperidinoxyl) as controller was evaluated by making a comparison with polymerizations using mono-functional initiators (BPO and TBEC). From the use of a design of experiments, the influence of the L531 initiator concentration, the TEMPO/initiator ratio, and the temperature on the reaction rate, molecular weights and polidispersity were determined, and an empirical model was generated. A kinetic mechanism has been proposed, from which mass balance and moment equations were derived for a batch reactor. The model was well adjusted to the experimental data with the estimation of some parameters. Lastly, a dynamic sensitivity analysis of the parameters was developed. It was shown both in experimental and simulation results that in the case of the bi-functional initiator L531, the reaction rate and molecular weights were increased when comparing to the performance of the mono-functional initiators keeping the livingness of the system. To the best of our knowledge, this is the first report of TEMPO-mediated polymerization of styrene using difunctional initiators.
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
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36

Bishop, Brenden. "Examining Random-Coeffcient Pattern-Mixture Models forLongitudinal Data with Informative Dropout." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu150039066582153.

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37

Soroburski, Idzi Rafał. "Przepowiadanie słowa Bożego w Prowincji Wniebowzięcia NMP Zakonu Braci Mniejszych w Polsce po Soborze Watykańskim II." Doctoral thesis, Katowice : Uniwersytet Śląski, 2021. http://hdl.handle.net/20.500.12128/21808.

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The current renewal of pastoral activity of the Church initiated at the Second Vatican Council included, among others, preaching with particular regard to delivering the homily. The Word of God is the foundation of preaching the Gospel, and It constantly shapes the life and the mission of the Church of all times. During the centuries of the Church’s history, the ministers appointed to proclaim the word of God by virtue of the priesthood established by Christ served the people of God by proclaiming the Gospel. The postulates of renewal of proclaiming the word of God concern also the preaching activity of the Order of Friars Minor (commonly called the Franciscans), who, united with the Roman Catholic Church, by their vows of obedience, and following the example of St. Francis of Assisi joined in the ministry of the word in the past centuries. Proclamation of the word of God is the task that the Franciscan community has been fulfilling from its very beginning, and it constitutes the character trait of the pastoral-evangelistic activity of the Order. The purpose of this dissertation is an attempt to show the current state of preaching undertaken and realized by the presbyters of the Assumption of the Blessed Virgin Mary Province of the Order of Friars Minor in Poland. It concerns mainly presenting the actual state of proclaiming the word of God in the Province (the theoretical objective) and showing the influence of the religious authority structures (the general religious structure of the Order and the structures of particular provinces) on the preaching (the practical objective). The primary source of this study are surveys conducted among the members of the Province. The survey results have been discussed in reference to the guidelines of the Church provided after the Second Vatican Council and the documents of the Order issued by the General Government and by the Provincial Government. The survey questionnaire has been created based on the present documents of the Order concerning the proclamation of the word of God and on the basis of the preaching methods developed by homiletics included in the literature on the subject. Presentation of the historical and legal foundations of the community established by St. Francis over 800 years ago, and description of the history and organizational structure of the Order and the Province, constitute the introduction to the study of characteristics of today’s reality in which the surveyed presbyters are working. The personnel and material status of the pastoral ministry provided by particular Houses of the Order in Poland and abroad has been presented. The analysis of survey results shows that proclaiming the word of God during the homily is fairly correct and reliable. More attention shall be paid to the time of preparation of the homily and its formal and material aspects. Proclaiming the Word of God by delivering the homily is of Christocentric and ecclesial nature, and it is enriched with the elements of the Franciscan spirituality and charism. Mariological and existential references play an important role in proclaiming of the word of God. Considerable attention is given to the simplicity of the message and to the length of the homily. Proclamation of the word of God by the Franciscans of the Assumption of the Blessed Virgin Mary Province in Poland is based on the religious formation of the Order, awareness of the monastic identity of each brother and on the constant development of their spiritual life according to the spirituality of St. Francis of Assisi. The love for the Church and the Gospel, rooted deeply in the Franciscan spirituality, is a driving force for the constant renewal of preaching performed by the Franciscans by order of the Church, for the Church and with the Church. The methods, forms and ways of making the preaching of the word of God up to date in the modern world help in the realization of this task. The aspect of the proclamation of the word of God that especially needs the preaching renewal is evangelization realized through parish missions and retreats. The conclusions and homiletic postulates included in this study show the areas which should be improved in order to refine the preaching skills among the brothers of the Province.
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Dolgov, Alex V. "EXPLORATION OF GRADIENT-TYPE POLY(ARYLENE ETHER)S VIA AN ABB' MONOMER SYSTEM." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1222006664.

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Gomes, de Souza Renata. "Aspectos ecológicos e introdução de mudas micorrizadas para revegetação de áreas de Dunas Mineradas no Litoral da Paraíba." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/425.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
A mineração é um dos fatores de degradação dos ambientes costeiros do Brasil, dificultando o estabelecimento e a sobrevivência das plantas e da comunidade microbiana do solo. Na mina de Mataraca, estado da Paraíba, a retirada da vegetação e a intensa movimentação do solo têm causado modificações no sistema, comprometendo o processo de regeneração natural. Este trabalho teve como objetivos principais contribuir para ampliar o conhecimento sobre a diversidade de fungos micorrízicos arbusculares (FMA) em áreas de dunas, gerar informações sobre o impacto da mineração e da revegetação na comunidade desses organismos e avaliar os efeitos da inoculação com FMA no desenvolvimento e na sobrevivência de mudas utilizadas na revegetação da área. Foram estudadas quatro áreas de dunas revegetadas há 16, 12, 8 e 4 anos, uma área de duna natural e uma sem cobertura vegetal a ser revegetada. Três espécies utilizadas na revegetação foram selecionadas: Guazuma ulmifolia Lam., Tabebuia roseo-alba (Ridl.) Sandw. e Tocoyena selloana Schum., sendo avaliadas as contribuições da inoculação com FMA e da adubação com esterco bovino no crescimento das plantas, em casa de vegetação e em campo. A retirada e estoque da camada superficial do solo para recapeamento das dunas exploradas é importante para o estabelecimento da vegetação, porém afeta a comunidade de FMA, diminuindo a quantidade e infectividade dos propágulos no solo. O plantio de mudas contribuiu para o restabelecimento de propágulos micorrízicos nas dunas revegetadas. Cerca de 90% das 24 espécies vegetais avaliadas apresentaram-se naturalmente colonizadas, sendo identificadas 29 espécies de FMA na rizosfera destas plantas. As três espécies vegetais testadas formaram associação com os FMA e os efeitos da simbiose variaram com a planta hospedeira, com os fungos utilizados, com as proporções de esterco adicionadas aos substratos e com as condições de casa de vegetação e de campo. De modo geral, a adição de 10% de esterco bovino favoreceu a micorrização e o crescimento das plantas
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40

Corten, Cathrin Carolin. "Synthese und Charakterisierung dünner Hydrogelschichten mit modulierbaren Eigenschaften." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1209463829168-95283.

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Im Mittelpunkt dieser Arbeit stand die Darstellung sensitiver Blockcopolymere und deren Gele, die als Ausgangsmaterialien in Sensor- und Aktorsystemen einsetzbar sind. Die Vereinigung verschiedener Ansprechparameter stellt erhöhte Anforderung an die Synthese. Geringe Ansprechzeiten lassen sich mit einer Gelgröße im µm-Bereich erreichen. Hydrogele dieser Größenordnungen können durch nachträgliche Vernetzung funktioneller linearer Polymere ermöglicht werden. Die Makroinitiatormethode ermöglichte den Aufbau verschiedener linearer photovernetzbarer Blockcopolymere. Zum Einen wurde das temperatursensitive P(n-BuAc)-block-P(PNIPAAm-co-DMIAAm) erhalten, des Weiteren gelang die Darstellung der multi-sensitiven Blockcopolymere P2VP-block-P(NIPAAm-co-DMIAAm) und P4VP-block-P(NIPAAm-co-DMIAAm). Die Blockcopolymere wurden mit variierenden Blocklängen und Verhältnissen sowie mit unterschiedlichem Vernetzergehalt dargestellt. Die Charakterisierung der Blockcopolymere erfolgte mittels 1H-NMR-Spektroskopie, GPC-Messungen (Zusammensetzung) und DSC-Messungen (thermische Eigenschaften). Das Löslichkeitsverhalten in wässrigen Medien wurde durch Dynamische Lichtstreuung bestimmt. Die Beschreibung des Quellverhaltens der vernetzten Schichten erfolgte durch vornehmlich durch optische Methoden (SPR/OWS, WAMS, Ellipsometrie). Die Veränderung des E-Moduls in Abhängigkeit äußerer Parameter konnte mittels AFM untersucht werden. Die Reaktion der Schichten wurde gegenüber Temperatur, pH-Wert und Salzkonzentrationen getestet. Die charakterisierten Filme konnten im Anschluss als sensitive Schichten in piezoresistiven Sensorsystemen verwendetet werden.
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41

Messerschmidt, Martin. "Partiell geschützte Blockcopolymere zur Darstellung von Polymerfilmen mit strukturierbarer und modifizierbarer Morphologie." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1164976535005-04944.

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Gemäß der Zielstellung der Dissertation wurden verschiedene partiell tert.-Butyl- (TBU) und tert.-Butyloxycarbonyl- (Boc) geschützte Blockcopolymere auf der Basis von Poly(4-hydroxystyrol) mit engen Molmassenverteilungen sowie mit verschiedenen Blockzusammensetzungen dargestellt. Die Synthese dieser partiell TBU- und Boc-geschützten Blockcopolymere umfasste drei wesentliche Schritte: 1) Darstellung von Makroinitiatoren mittels NMRP, 2) Synthese von orthogonal geschützten Precursor-Blockcopolymeren durch Reinitiierung der Makroinitiatoren in Gegenwart eines weiteren orthogonal geschützten Monomeren und 3) orthogonale und quantitative polymeranaloge Umsetzungen ausgehend von den orthogonal geschützten Precursor-Blockcopolymeren. Mit den partiell TBU- und Boc-geschützten Blockcopolymeren wurden dünne Polymerfilme mittels „dip-coating“ präpariert. Die Untersuchung der Topographie und Morphologie der Filme erfolgte mit dem AFM. Aus den erhaltenen Topographie- und Phasenverschiebungsbildern ging eindeutig hervor, dass die verschiedenen Blöcke der jeweiligen partiell TBU- und Boc-geschützten Blockcopolymere in allen Polymerfilmen phasensepariert vorlagen. Reguläre Mikrostrukturen konnten allerdings nur bei den Polymerfilmen erhalten werden, deren Blockcopolymere sich allesamt durch asymmetrische Blockzusammensetzungen auszeichnen. Auf der Grundlage des statistischen Modellpolymeren Poly(styrol-r-4-hydroxystyrol) konnte ferner gezeigt werden, dass sich die phenolischen Hydroxylgruppen durch die Umsetzung mit Propargylbromid quantitativ in Propargylether-Gruppen umwandeln lassen und diese dann ihrerseits mit Hilfe der Cu(I)-katalysierten 1,3-dipolaren Cycloaddition (Click-Chemie) weiter mit einer Reihe von verschiedenen Aziden funktionalisiert werden können.
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42

Marquezi, Marina Chiarelli. "Comparação de metodologias para a estimativa do número mais provável (NMP) de coliformes em amostras de água." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-21102010-160234/.

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Em quase todos os ambientes aquáticos são encontrados diversos microrganismos, entre eles alguns patogênicos ao homem, que tem como rota de transmissão o ciclo fecal-oral. Pelo fato de a água ser o alimento mais consumido pela população, ela está associada a diversos casos de doenças e de riscos à saúde pública. Assim, o controle da qualidade da água antes do seu consumo é essencial, e para a garantia de sua qualidade devem ser feitas análises que buscam indicar a contaminação por material de origem fecal. O grupo de bactérias mais usado para a determinação de contaminação fecal é o grupo coliformes totais, que tem como subgrupo os coliformes termotolerantes. A bactéria Escherichia coli é integrante do grupo coliforme termotolerante, e é a mais indicada para determinação de contaminação fecal pelo fato de estar presente em grande quantidade em fezes de humanos e animais de sangue quente. Para a análise de bactérias do grupo coliformes totais e E. coli há diversos métodos, entre eles o método convencional de fermentação em tubos múltiplos (FTM) e os métodos rápidos Colilert e Colitag. Este trabalho teve como objetivo comparar estes três métodos para tais análises em amostras de água provenientes de pontos com contaminações distintas (abastecimento, bica e rio), assim como comparar as contagens encontradas de coliformes termotolerantes e E. coli pelo método FTM. Os métodos rápidos Colilert e Colitag se mostraram equivalentes ao FTM nas análises de coliformes totais em amostras de água provenientes de bica e de abastecimento, e nas análises de E. coli em amostras de água de abastecimento, da bica e do rio. Para as análises de coliformes totais em amostras de água do rio o método FTM apresentou uma diferença significativa em relação ao método Colilert e Colitag. Ambos os métodos rápidos não diferiram entre si. A diferença encontrada entre estes métodos nestas análises pode ter ocorrido devido à presença de Aeromonas nas amostras, que podem ter gerado resultados falso-positivos nos métodos rápidos, superestimando a contagem de coliformes totais; ou pela maior capacidade dos métodos rápidos em recuperar células injuriadas de coliformes totais, detectando uma quantidade maior destas bactérias. Na comparação das contagens encontradas para coliformes termotolerantes e E. coli nas mesmas amostras foi encontrada uma diferença significativa. Este resultado é explicado pelo fato de o grupo coliforme termotolerante incluir bactérias de origem não exclusivamente fecal, tais como Enterobacter e Klebsiella, o que pode superestimar a contaminação fecal da amostra. Já a E. coli tem origem exclusivamente fecal, sendo mais indicada para tal análise. Assim, como os métodos rápidos se mostraram equivalentes ao método convencional estudado, devese preferir o uso dos métodos rápidos, que dão o resultado em 24 horas, indicando a qualidade da água a tempo de evitar o uso desta pela população. Na escolha entre as bactérias do grupo coliformes termotolerantes e a E. coli para a indicação da contaminação fecal, deve-se preferir o uso da E. coli.
In almost all aquatic environments are found in various microorganisms, including some pathogenic to man, which route of transmission is the fecal-oral cycle. Because the water is the food most consumed by people, it is associated with several cases of diseases and risks to public health. Thus, control of water quality prior to consumption is essential, and to guarantee its quality must be made analysis seeking to indicate contamination by fecal material of origin. The group of bacteria most commonly used for the determination of fecal contamination is the total coliform group, which has as subgroup thermotolerant coliforms. The bacterium Escherichia coli is a member of the group thermotolerant coliform, and is most suitable for determination of fecal contamination by being present in large quantities in feces of humans and warmblooded animals. For the analysis of bacteria of the group coliform and E. coli there are several methods, including the conventional method Multiple Tube Fermentation (MTF), and the rapid methods Colilert and Colitag. This study aimed to compare these three methods for analysis in water samples from different points with different contamination (supply, fountain and river) and compare the count found for thermotolerant coliform and E. coli by the method FTM. The methods Colilert, Colitag and FTM were equivalent in the analysis of total coliform in water samples from the fountain and supply, and the analysis of E. coli in samples of supply, fountain and river. For analysis of total coliform in water samples from the river, FTM method showes a significant difference compared to the methods Colilert and Colitag. Both rapid methods did not differ. The difference between these methods in these tests may be due to the presence of Aeromonas in the samples, which may have generated false-positive results in rapid methods, overestimating the total coliform count; or the largest capacity of rapid methods in recovering injured cells of coliforms, detecting a larger amount of these bacteria. Comparing the scores found for thermotolerant coliform and E. coli in the same samples was found a significant difference. This result is explained by a thermotolerant coliform group include bacteria not exclusively fecal origin, such as Klebsiella and Enterobacter, which may overestimate the faecal contamination of the sample. Since E. coli is exclusively fecal origin, being more suitable for such analysis. So, as rapid methods showed to be equivalent to the conventional method studied, one should prefer the use of rapid methods that give results in 24 hours, indicating the water quality in time to prevent its use in the population. In choosing between coliform thermotolerant bacteria and E. coli for the indication of fecal contamination, it is preferable to use E. coli.
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43

Ngazoa, Elise Solange. "Untersuchung der eisenabhängigen Regulation des trypanosomalen Transferrinrezeptors in Trypanosoma brucei und biochemische Charakterisierung einer T. brucei-NMP-Kinase." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968620264.

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44

Pino, Guillaume. "Synthèse et auto-assemblage de copolymères à blocs à paramètre d’interaction de Flory-Huggins élevé." Thesis, Bordeaux, 2021. http://www.theses.fr/2021BORD0098.

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Cette thèse porte sur la synthèse de copolymères à blocs (BCPs) à haut pouvoir de ségrégation pour des applications en nanolithographie. La voie de synthèse qui a été retenue est la polymérisation radicalaire contrôlée par les nitroxydes ou NMP. Parmi tous les copolymères à blocs synthétisés, nous avons choisi de nous intéresser plus particulièrement à l'association de blocs 'hydrophile' et 'hydrophobe' à squelettes polystyrène. Le bloc hydrophile poly(3,4-dihydroxystyrène) (PDHS) s'est montré très intéressant en association avec les blocs poly(4-tertbutylstyrène) (PtBS) et poly(4-triméthylsilylstyrène) (PTMSS) formant respectivement les copolymères à blocs PDHS-b-PtBS et PDHS-b-PTMSS. Ainsi des valeurs de χ très élevées ont pu être quantifiées de l'ordre de 0,7 par exemple pour le PDHS-b-PtBS. L'avantage du bloc PTMSS tient au fait qu'il a permis d'amplifier le phénomène de contraste en gravure. Le bloc PDHS a ensuite été remplacé par le poly(4-méthylétherglycérolstyrène) (PMGS) afin de faire varier notamment les caractéristiques thermiques et d'étudier leur effet sur l'auto-assemblage de copolymères PtBS-b-PMGS. Enfin, les capacités d'infiltration spécifique du bloc PDHS par un précurseur métallique ont mis en évidence la formation d'un masque dur et d'un réseau double oxyde pour respectivement le PDHS-b-PtBS et le PDHS-b-PTMSS
This thesis concerns the synthesis of block copolymers (BCPs) with high segregation power for nanolithography applications. The main synthesis patway that has been followed is the controlled radical polymerization by nitroxides or NMPs. Among all the synthesized block copolymers, we have chosen to focus on the association of 'hydrophilic' and 'hydrophobic' blocks with polystyrene backbones. The hydrophilic poly(3,4-dihydroxystyrene) (PDHS) block has proved to be very interesting in association with the poly(4-tertbutylstyrene) (PtBS) and poly(4-trimethylsilylstyrene) (PTMSS) blocks forming respectively the PDHS-b-PtBS and PDHS-b-PTMSS block copolymers. High χ values could thus be quantified in the range of 0.7 for PDHS-b-PtBS, for example. The main advantage of the PTMSS block is about the contrast amplification during etching. The PDHS block was then replaced by poly(4-methyletherglycerolstyrene) (PMGS) in order to vary, in particular, the thermo-mechanical features and to study in particular their effect on the self-assembly of PtBS-b-PMGS copolymers. Finally, the specific infiltration capacities of the PDHS block by a metallic precursor highlighted the formation of a hard mask and a double oxide network for PDHS-b-PtBS and PDHS-b-PTMSS respectively
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45

Dommanget, Cédric. "Polymérisation radicalaire contrôlée : le défi de l'éthylène." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10216/document.

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Les travaux présentés dans cette thèse portent sur le contrôle de la polymérisation radicalaire de l'éthylène à basse pression (200 bar) et basse température (70 °C) et sur la synthèse de copolymères à blocs contenant au moins un segment de polyéthylène. Quatre techniques de polymérisation, couramment utilisées en ingénierie macromoléculaire, ont été étudiées : NMP, CMRP, RAFT/MADIX et ESCP. Nos études sur le nitroxyde SG1 (NMP) et le bis(acétylacétonate) de cobalt (CMRP) ont montré que ces composés sont inefficaces pour contrôler la polymérisation de l'éthylène. Un comportement inattendu du bis(acétylacétonate) de cobalt a cependant été mis en évidence. Il semblerait que ces complexes de cobalt favorisent les réactions de couplage entre les radicaux propagateurs. En revanche, la première polymérisation radicalaire contrôlée de l'éthylène a été atteinte grâce à l'utilisation de xanthates (RAFT/MADIX). Les polyéthylènes synthétisés possèdent des masses molaires qui augmentent linéairement avec la conversion et des dispersités faibles. Le caractère pseudo-vivant de la réaction a été démontré par la synthèse de copolymères à blocs poly(acétate de vinyle)-b-polyéthylène. L'utilisation de nitrones (ESCP) a également permis l'introduction d'une fonction réactive au centre des chaînes de polyéthylène et la synthèse de copolymères triblocs de type ABA, où les blocs latéraux A sont en polystyrène ou polyacrylate et le bloc central B est en Polyéthylène
The work presented in this thesis displays the controlled radical polymerization of ethylene at low temperature (70 °C) and low pressure (200 bar) and the synthesis of block copolymers featuring polyethylene segments. Four polymerization techniques, commonly used in macromolecular engineering, were studied: NMP, CMRP, RAFT/MADIX and ESCP. Our investigation of the use of SG1 nitroxide (NMP) and cobalt (II) acetylacetonate (CMRP) as controlling agents demonstrated their inability to control the polymerization of ethylene. Nonetheless, an unexpected reaction with cobalt (II) acetylacetonate was observed. The coupling reaction between propagating radicals appeared to be favored by the presence of this compound. On the other hand, the first controlled polymerization of ethylene was successfully achieved by using xanthate (RAFT/MADIX). A linear increase of molecular weight with conversion and low polydispersities were observed for the produced polyethylenes. The reaction was demonstrated to be a pseudo-living polymerization by the synthesis of block copolymers poly(vinyl acetate)-b-polyethylene. In addition, midchain-functionalized polyethylenes and ABA type block copolymers, with polystyrene or polyacrylate as the A block and polyethylene as the B block, were also prepared using nitrone based polymerization technique (ESCP)
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46

Neary, Stephen. "An investigation of thiadiazolidines and related compounds for use as ligands in metal mediated catalysis." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9122.

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This thesis describes the investigation of thiadiazolidine 1-oxides and structurally related compounds as ligands in palladium catalysis. The introduction will provide background information on subjects related to the work of the main project. Palladium catalysed cross couplings, namely the Heck and Tsuji-Trost reactions, will feature prominently and will be discussed in basic detail. A general outline of different classes of ligands used in palladium catalysis will also be put forward. Extraneous factors which affect catalyst reactivity will also be discussed, including the use of microwave irradiation and the effect of additives. Special attention is paid towards sulfur containing ligands. As their use has been relatively limited this will also include other areas of catalysis. Investigations into the synthesis of esermethole prompt a general background of methods of synthesising oxindoles and also examples of previous syntheses of the compound. The second chapter begins by describing the initial exploratory work, the testing of a thiadiazolidine 1-oxide compound as a ligand for the Heck reaction. Aryl iodides are successfully coupled to a range of styrenes and α,β-unsaturated esters in excellent yields under microwave conditions. Aryl bromides are also successfully coupled after some optimisation. In many cases the presence of tetrabutylammonium bromide is required to prevent shattering of the sealed microwave vial. A range of differently substituted thiadiazolidine 1-oxides were synthesised in order to establish a pattern of reactivity based on steric and electronic factors. Structurally related chiral compounds were also synthesised, including the first reported enantiomerically pure thiadiazol-3-one 1-oxide and thiatriaza-indene 3-oxide systems chiral at the sulfur atom. The synthesis of oxindoles using palladium mediated and non-catalytic chemistry was also investigated. Investigations into the synthesis of esermethole were undertaken; the key stereoinducing reaction, the decarboxylative asymmetric allyic alkylation reaction, achieved a 46% ee. A formal synthesis of esermethole was outlined in 8 steps from commercially available material. The third chapter is the experimental section and is dedicated to the methods of synthesis and characterization of the compounds mentioned in the previous chapter. X-ray reports regarding the crystallographic representation of the structures presented in chapter two are provided in appendix A.
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47

Müntzing, Daniel. "Evaluating NMP Quality of Service : Experiment with JackTrip regarding Latency versus Packet Jitter/Dropouts with High Quality Audio via LAN and WAN." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-16169.

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This study has developed a method to create an, to a big extent, automated testing system for NMP (Networked Music Performance) communication over LAN and WAN to be able to benchmark the UDP streaming engine JackTrip using a client-server model. The method is not locked into using JackTrip only, it could be used to do experiments with other engines too. The study tried to answer the question if latency correlates to amount of correctly aligned audio, and to what extent the audio is correctly aligned in respect to tolerated latency (based on earlier research) when at least two musicians remote-conducting musical pieces together. There were 13 different buffer settings tested, which used no redundancy and redundancy of 2, and which were sent through 4 different LAN/WAN-scenarios. A big dataset was produced, with about 82 minutes’ worth of audio per test. To post-process the data a phase cancelling method was used to measure correctly aligned audio, while the latency was measured by counting the number of samples from the start of each audio file to the first sample that were not null or not under a certain threshold. The results showed clear correlations of buffer sizes impact of latency and amount of correctly audio sent over the network. If the buffer sizes are greater, it will produce higher latency and increase the amount of correctly aligned audio, and on the opposite side, if using less buffer, it will produce lower latencies and less correctly aligned amount of audio. The study also showed that there was very little impact of using higher redundancies, both regarding latency and amount of correctly audio. When analysing the amount of correct data when respecting the tolerated level of latency, the study showed a support for correctly aligned amount of streamed audio up to 65% when using JackTrip.
Den här studien har utvecklat en metod för att skapa ett, till stor del, automatiserat testsystem för NMP-kommunikation (Networked Music Performance) över LAN och WAN för att kunna prestandatesta den UDP-strömmande ljudmotorn JackTrip, med en klient-server-modell. Metoden är inte låst till att endast användas med JackTrip, den kan användas för att göra experiment med andra motorer också. Studien försökte svara på frågorna om latens korrelerar med mängden korrekt justerat ljud, och till hur stor del som ljudet är korrekt justerad med hänsyn till tolererbar latens (baserat på tidigare undersökning) när minst två musiker fjärrmusicerar tillsammans. Det testades 13 olika buffertinställningar, som använde ingen redundans samt med redundans på 2, och som kördes genom 4 olika LAN / WAN-scenarier. En stor datamängd producerades, med ca 82 minuters ljud per test. För att post-bearbeta data användes en fas-elimineringsmetod för att mäta mängden korrekt justerat ljud, medan latensen var uppmätt genom att räkna antalet samplingar från starten av varje ljudfil till den första samplingen som inte var innehållslös eller inte under ett specifikt tröskelvärde. Resultaten visade tydlig korrelation av buffertstorlekens påverkan av latens och mängd korrekt ljud skickat över nätverket. Om buffertstorlekarna är större kommer det att ge högre latens och öka mängden korrekt justerat ljud, och tvärtom, om mindre buffert används, kommer det att ge lägre latens och mindre rätt justerad mängd ljud. Studien visade också att det gav mycket liten effekt att använda högre redundans, både vad gällande latens och mängden korrekt ljud.  Vid analys av mängden korrekta data med hänsyn till den tolererade latensnivån visade studien ett stöd för korrekt justerat mängd av strömmat ljud upp till 65% vid användning av JackTrip.
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48

Fahad, Azeemi Muhammad. "HydraNetSim : A Parallel Discrete Event Simulator." Thesis, KTH, Kommunikationssystem, CoS, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98905.

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Abstract:
Discrete event simulation is the most suitable type of simulation for analyzing a complex system where changes happen at discrete time instants. Discrete event simulation is a major experimental methodology in several scientific and engineering domains. Unfortunately, a conventional discrete event simulator cannot meet with increasing demands of computational or the structural complexities of modern systems such as peer-to-peer (P2P) systems; therefore parallel discrete event simulation has been a focus of researchers for several decades. Unfortunately, no simulator is regarded as a standard which can satisfy the demands of all kinds of applications. Thus while given a simulator yields good performance for a specific kind of applications, it may failed to be efficient for other kinds of applications. Furthermore, although technological advancements have been made in the multi-core computing hardware, none of the mainstream P2P discrete event simulators is designed to support parallel simulation that exploits multi-core architectures. The proposed HydraNetSim parallel discrete event simulator (PDES) is a step toward addressing these issues. Developing a simulator which can support very large numbers of nodes to realize a massive P2P system, and can also execute in parallel is a non-trivial task. The literature review in this thesis gives a broad overview of prevailing approaches to dealing with the tricky problems of simulating a massive, large, and rapidly changing system, and provides a foundation for adopting a suitable architecture for developing a PDES. HydraNetSim is a discrete event simulator which allows parallel simulation and exploits the capabilities of parallelization of modern computing hardware. It is based on a novel master/slave paradigm. It divides the simulation model into a number of specific slaves (a cluster of processes) considering the number of cores provided by the underlying computing hardware. Each slave can be assigned to a specific CPU on a different core. Synchronization of the slaves is achieved by proposing a variant of the classic Null-Message Algorithm (NMA) with a focus on keeping the synchronization overhead as low as possible. Furthermore, HydraNetSim provides log information for debugging purposes and introduces a new mechanism of gathering and writing simulation results to a database. The experimental results show that the sequential counterpart of HydraNetSim (SDES) takes 41.6% more time than HydraNetSim-2Slave and 23.6% than HydraNetSim-3Slave. HydraNetSim-2Slave is 1.42 times faster, consumes 1.18 times more memory, and supports 2.02 times more nodes than a sequential discrete event simulator (SDES). Whereas, HydraNetSim-3Slave executes 1.24 times faster, consumes 2.08 times more memory, and supports 3.04 times more nodes than SDES. The scaling factor of HydraNetSim is ⌈(β-1)*102.04%⌉ of the maximum numbered of nodes supported by SDES; where β is the number of slaves.
Diskret händelsesimulering är den mest passande typen av simulering för att analysera ett komplext system där förändringar sker i diskreta tidpunkter. Diskret händelsesimulering är en stor experimentell metod i flera vetenskapliga och tekniska områden. Tyvärr kan en konventionell diskret händelse simulator uppfyller inte med ökande krav på beräkningsprogram eller strukturella komplexiteten av moderna system som peer-to-peer (P2P) system, och därför parallellt diskret händelse simulering har varit ett fokus för forskare under flera årtionde. Tyvärr ingen simulator ansåg som en standard som kan uppfylla kraven på alla typer av applikationer. Så samtidigt få en simulator ger bra prestanda för en specifik typ av applikationer kan det inte vara effektivt för andra typer av applikationer. Även om tekniska framsteget har gjorts i multi-core datorhårdvara, är ingen av de vanliga P2P händelsestyrd simulatorer för att stödja parallella simulering som utnyttjar flera kärnor arkitekturer. Den föreslagna HydraNetSim parallella diskret händelse simulator (PDES) är ett steg mot att fokusera på dessa frågor. Utveckla en simulator som kan stödja ett mycket stort antal noder för att realisera en massiv P2P-system, och kan även utföra parallellt är en icke-trivial uppdrag. Litteraturstudien i denna tesen ger en bred översikt över aktuell metoder för att hantera de svåra problem som simulerar en massiv, stor och snabbt ändra system och ger en grund för att adoptera en passande struktur för att utveckla ett PDES. HydraNetSim är en diskret händelse simulator som gör det möjligt parallellt simulering och utnyttjar funktionerna i parallellisering av modern datorhårdvara. Det är baserat på en ny master / slav paradigm. Den delar simuleringsmodellen i ett antal specifika slavar (ett kluster av processer) med tanke på antalet kärnor som tillhandahålls av den underliggande datorhårdvara. Varje slav kan tilldelas en specifik CPU på en annan kärna. Synkronisering av slavarna uppnås genom att föreslå en variant av det klassiska Null-Message Algorithm (NMA) med fokus på att hålla simuleringen overhead så lågt som möjligt. Dessutom ger HydraNetSim log information för felsökning ändamål och inför en ny mekanism för att samla in och skriva simuleringar resultat till en databas. De experimentella resultaten visar att den sekventiella motsvarigheten till HydraNetSim (SDES) tar 41,6% mer tid än HydraNetSim-2Slave och 23,6% mindre än HydraNetSim-3Slave. HydraNetSim-2Slave är 1,42 gånger snabbare, förbrukar 1,18 gånger mer minne, och stöder 2.02 gånger fler noder än en sekventiell händelsestyrd simulator (SDES). I HydraNetSim-3Slave kör 1.24 gånger snabbare, förbrukar 2,08 gånger mer minne, och stöder 3,04 gånger fler noder än SDES. Skalfaktorn av HydraNetSim är ⌈(β-1)*102.04%⌉ av den maximala numrerade noder som stöds av SDES; där β är antalet slavar.
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49

Trindade, Manuel Joaquim Fonseca. "Estudo da micobiota associada ao lenho de Pinus pinaster afetado pelo nemátode-da-madeira-do-pinheiro (Bursaphelenchus xylophilus) em Portugal." Master's thesis, ISA, 2019. http://hdl.handle.net/10400.5/21294.

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50

Martinez, Michael. "Simulation ab initio de modules d'intérêt biologique : modes de vibrations pour la spectroscopie infrarouge." Paris 6, 2006. http://www.theses.fr/2006PA066620.

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