Log in

Relevant bibliographies by topics / Ziegler / Dissertations / Theses

To see the other types of publications on this topic, follow the link: Ziegler.

Dissertations / Theses on the topic 'Ziegler'

Author: Grafiati

Published: 4 June 2021

Last updated: 16 June 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Ziegler.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Guégan, Stéphane. "Jules Ziegler peintre." Paris 4, 2000. http://www.theses.fr/1999PA040179.

Full text

Abstract:

En proposant de reconsidérer l'œuvre peint de Jules Ziegler (1804-1856), cette étude ne se borne pas à remettre en lumière un acteur oublié de l'ingrisme en examinant ses principaux tableaux et le décor de l'abside de l'église de la Madeleine l'approche stylistique se double d'une mise en situation qui conduit à réintégrer pleinement ce familier des milieux littéraires et des débats critiques de la Monarchie de juillet au cœur du romantisme français.

APA, Harvard, Vancouver, ISO, and other styles

2

Gregory, Lorna Anne. "Ziegler spectra of valuation rings." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/ziegler-spectra-of-valuation-rings(aed20f0f-16c6-40a2-9187-2cc60eae6e9a).html.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Wittstadt, Ursula [Verfasser], Felix [Akademischer Betreuer] Ziegler, Felix [Gutachter] Ziegler, and Ferdinand [Gutachter] Schmidt. "Experimentelle und modellgestützte Charakterisierung von Adsorptionswärmeübertragern / Ursula Wittstadt ; Gutachter: Felix Ziegler, Ferdinand Schmidt ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2018. http://d-nb.info/116785652X/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Hippich, Markus [Verfasser], Anette-Gabriele [Akademischer Betreuer] Ziegler, Fabian [Gutachter] Theis, and Anette-Gabriele [Gutachter] Ziegler. "Heterogeneity of Childhood Diabetes / Markus Hippich ; Gutachter: Fabian Theis, Anette-Gabriele Ziegler ; Betreuer: Anette-Gabriele Ziegler." München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/120419999X/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Rabinovich, Daniel. "Just one word: Plastics." Revista de Química, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/100995.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Theaker, Giles William. "tert-Butylstyrene in Ziegler-Natta polymerisations." Thesis, University of Warwick, 2010. http://wrap.warwick.ac.uk/3799/.

Full text

Abstract:

Chapter One introduces Ziegler-Natta polymerisation through mechanisms of polymerisation encompassing activation, propagation and termination of a polymer. The mechanisms of monomer insertion and their effects on polymer microstructure are shown. Several important catalysts of different design (metallocenes, half-sandwich complexes and post-metallocenes) are shown. Chapter Two focuses on ethene/styrene and ethene/tert-butylstyrene copolymerisations using commercially available metallocene catalysts, with the goal of increasing styrenic co-monomer incorporation without sacrificing productivity. Terpolymers of the above systems with hexene are briefly discussed. Chapter Three looks at ethene/tert-butylstyrene copolymerisations using post-metallocene catalysts, focusing specifically on zirconium based salicylaldimine species. The dramatic effects of modified styrenic monomers on these catalysts is shown. Chapter Four shows how zirconium based salicylaldimine catalysts and similar species can be activated so as to homopolymerize tert-butylstyrene in the presence of H2 and other monomers. A mechanistic explanation of the effects is postulated. The effects of ligand modification are explored, leading to the discovery of the active species involved in the above homopolymerisations. Chapter Five covers experimental details relating to the above chapters, including synthesis of precursors, ligands, precatalysts and polymerisation methodologies.

APA, Harvard, Vancouver, ISO, and other styles

7

Ziegler, Julius [Verfasser]. "Optimale Trajektorienplanung für Automobile / Julius Ziegler." Karlsruhe : KIT Scientific Publishing, 2017. http://www.ksp.kit.edu.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Jahnke, Anna [Verfasser], Felix [Akademischer Betreuer] Ziegler, Felix [Gutachter] Ziegler, and André [Gutachter] Bardow. "Untersuchung des Honigmann-Prozesses zur thermochemischen Energiespeicherung / Anna Jahnke ; Gutachter: Felix Ziegler, André Bardow ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2019. http://d-nb.info/1188697536/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Nyc, Julia Katharina Elisabeth [Verfasser], Anette-Gabriele [Akademischer Betreuer] Ziegler, Gerhard [Gutachter] Schneider, and Anette-Gabriele [Gutachter] Ziegler. "INIT II-Atemgasstudie / Julia Katharina Elisabeth Nyc ; Gutachter: Gerhard Schneider, Anette-Gabriele Ziegler ; Betreuer: Anette-Gabriele Ziegler." München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/1236342909/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Stemmer, Lea [Verfasser], Albert [Akademischer Betreuer] Ziegler, and Albert [Gutachter] Ziegler. "Frauen in MINT: Ein systemischer Erklärungsansatz der Leaky Pipeline / Lea Stemmer ; Gutachter: Albert Ziegler ; Betreuer: Albert Ziegler." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1212663705/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Albers, Jan [Verfasser], Felix [Akademischer Betreuer] Ziegler, Felix [Gutachter] Ziegler, and Christian [Gutachter] Schweigler. "Erweiterung einer Berechnungsmethode für die Regelung von Absorptionskälteanlagen / Jan Albers ; Gutachter: Felix Ziegler, Christian Schweigler ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2019. http://d-nb.info/1195039344/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Stinner, Karl [Verfasser], Felix [Akademischer Betreuer] Ziegler, Felix [Gutachter] Ziegler, and Petra [Gutachter] Bittrich. "Dampferzeugeroptimierung zur Abwärmenutzung mittels Dampfkraftprozess an mobilen Verbrennungsmotoren / Karl Stinner ; Gutachter: Felix Ziegler, Petra Bittrich ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2018. http://d-nb.info/1161007032/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Hunt, Sarah [Verfasser], Felix [Akademischer Betreuer] Ziegler, Felix [Gutachter] Ziegler, and René [Gutachter] Rieberer. "Einfluss des Lösungsvolumenstroms auf das Betriebsverhalten von Absorptionskälteanlagen / Sarah Hunt ; Gutachter: Felix Ziegler, René Rieberer ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2020. http://d-nb.info/1220355941/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Ziegler, Konstantin [Verfasser]. "Counting classes of special polynomials / Konstantin Ziegler." Bonn : Universitäts- und Landesbibliothek Bonn, 2015. http://d-nb.info/1077289596/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Ziegler, Andreas Gregor [Verfasser]. "Zur verkürzten Systemlebensdauerprüfung von Zahnradgetrieben / Andreas Ziegler." München : Verlag Dr. Hut, 2011. http://d-nb.info/1018981829/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Shiga, Akinobu. "THEORETICAL STUDY OF ZIEGLER-NATTA OLEFIN POLYMERIZATION." Kyoto University, 1998. http://hdl.handle.net/2433/182364.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Bächle, Felix [Verfasser], and Thomas [Akademischer Betreuer] Ziegler. "Glycokonjugierte Phthalocyanine / Felix Bächle ; Betreuer: Thomas Ziegler." Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1204422214/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Mittermaier, Martin [Verfasser], Felix [Akademischer Betreuer] Ziegler, Andrea [Gutachter] Luke, and Felix [Gutachter] Ziegler. "Theoretische Untersuchung des Wärme- und Stoffübergangs am laminaren Fallfilm / Martin Mittermaier ; Gutachter: Andrea Luke, Felix Ziegler ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2018. http://d-nb.info/116407637X/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Wilkes, Martin [Verfasser], Christine [Akademischer Betreuer] [Gutachter] Ziegler, and Clemens [Gutachter] Glaubitz. "Single-particle cryo-EM structures of oligomeric membrane protein complexes / Martin Wilkes ; Gutachter: Clemens Glaubitz, Christine Ziegler ; Betreuer: Christine Ziegler." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2016. http://d-nb.info/1120493412/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Wu, Long. "Ethylene polymerization over morphology-controlled Ziegler-Natta catalysts." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0016/NQ46947.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Ziegler, Birgit [Verfasser]. "Professionalisierung im Studium - Anspruch und Wirklichkeit / Birgit Ziegler." Aachen : Shaker, 2004. http://d-nb.info/1170545122/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Ziegler, Reinhold Thomas [Verfasser]. "Gefäßchirurgische Optionen bei hochbetagten Patienten / Reinhold Thomas Ziegler." Ulm : Universität Ulm, 2020. http://d-nb.info/121656406X/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Castro, Carlos A., Liliana Eguren, and Richard P. Korswagen. "CATALIZADORES Ziegler-Natta utilizados para polimerizar propileno y etileno." Revista de Química, 2017. http://repositorio.pucp.edu.pe/index/handle/123456789/99207.

Full text

Abstract:

A 35 años de su descubrimiento, la polimerización del propileno y etileno es hoy en día uno de los mayores procesos industriales. Se comienza con una breve reseña histórica, para luego resaltar las estructuras, propiedades y usos del polipropileno y polietileno, continuando con la polimerización de los monómeros respectivos, la estereorregulación en la polimerización del propileno y los catalizadores Ziegler-Natta utilizados para polimerizar propileno y etileno empleando titanio y otros metales de transición.

APA, Harvard, Vancouver, ISO, and other styles

24

Kaltwasser, Susann [Verfasser], Christine [Akademischer Betreuer] [Gutachter] Ziegler, and Volker [Gutachter] Dötsch. "Structural investigations of stressosome complexes by single-particle cryo-electron microscopy / Susann Kaltwasser ; Gutachter: Volker Dötsch, Christine Ziegler ; Betreuer: Christine Ziegler." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2016. http://d-nb.info/1114270733/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Becker, Maike [Verfasser], Annette-Gabriele [Akademischer Betreuer] Ziegler, Hannelore [Gutachter] Daniel, and Annette-Gabriele [Gutachter] Ziegler. "Mechanisms of tissue-specific T cell tolerance in diabetes / Maike Becker ; Gutachter: Hannelore Daniel, Annette-Gabriele Ziegler ; Betreuer: Annette-Gabriele Ziegler." München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/1209269813/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Debatin, Tobias [Verfasser], Albert [Akademischer Betreuer] Ziegler, and Albert [Gutachter] Ziegler. "Was messen IQ-Werte? – Eine aktualisierte Interpretation unter Berücksichtigung moderner Methoden und Perspektiven / Tobias Debatin ; Gutachter: Albert Ziegler ; Betreuer: Albert Ziegler." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1206734094/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Dai, Shuanghua Patrick. "X-ray scattering and thermal analysis study of isotactic polypropylene /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2000.

Find full text

Abstract:

Thesis (Ph.D.)--Tufts University, 2000.<br>Submitted to the Dept. of Physics. Adviser: Peggy Cebe. Includes bibliographical references (leaves 246-251). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

APA, Harvard, Vancouver, ISO, and other styles

28

Ziegler, Pascal [Verfasser]. "Dynamische Simulation von Zahnradkontakten mit elastischen Modellen / Pascal Ziegler." Aachen : Shaker, 2012. http://d-nb.info/106773564X/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Ziegler, Tobias [Verfasser]. "Struktur-Eigenschafts-Beziehungen in lamellaren Metallmatrix-Verbundwerkstoffen / Tobias Ziegler." Aachen : Shaker, 2010. http://d-nb.info/1080767185/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Ziegler, Karolin [Verfasser]. "Isolierung neuer Fullerene und Synthese von Buckybowls / Karolin Ziegler." Wuppertal : Universitätsbibliothek Wuppertal, 2013. http://d-nb.info/1033568724/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Ziegler, Jannis [Verfasser]. "Prädiktoren der Letalität beim schweren akuten Lungenversagen / Jannis Ziegler." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2019. http://d-nb.info/1194373151/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Nietzel, Sven Ingo [Verfasser]. "Organische Trägermaterialien für Ziegler-Natta-Katalysatoren / Sven Ingo Nietzel." Mainz : Universitätsbibliothek Mainz, 2018. http://d-nb.info/1149975776/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Kraft, Jochen [Verfasser], and Thomas [Akademischer Betreuer] Ziegler. "Asymmetrische Übergangsmetallkatalyse mit Kohlenhydratliganden / Jochen Kraft ; Betreuer: Thomas Ziegler." Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/1165236400/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Lutz, Marietjie. "Metallocene and Ziegler-Natta catalyzed polypropylene utilizing 1-heptene." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52334.

Full text

Abstract:

Thesis (MSc)--Stellenbosch University, 2001.<br>ENGLISH ABSTRACT: This study concerns the copolymerization of propylene with l-heptene. The percentage of l-heptene used as co-monomer in the polymerization reactions was varied from 5% to 20% in order to compare a variety of polymers with different percentages of comonomer incorporated. A variety of different catalysts were used for these polymerizations. Two metallocene catalysts were used: (A) the isospecific catalyst, rae- [ethylene bis(l-indenyl)]zirconium dichloride (rac-Et(Ind)2ZrCh2) and (B) the silylene-bridged catalyst, rac-Me2Si(2-MeBenz[ e]Ind)zZrCh2. Methylaluminoxane (MAO) was used as cocatalyst for these two metallocene catalysts. Another series of polymerization reactions was done using a Ziegler-Natta catalyst, namely TiCb/AlEt3/Si02. Characterization of the copolymers included usmg high temperature gel permeation chromatography (HTGPC) for molecular mass and molecular mass distributions, differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) to investigate the thermal and mechanical properties of the copolymers, nuclear magnetic resonance spectroscopy (NMR) for information concerning the microstructures of the copolymers and crystallization analysis fractionation (CRYSTAF) to investigate the short chain branching of the copolymers. Comparative studies were done on the different catalysts and the polymer properties. The synthesized polymers were also compared with copolymers of propylene with l-hexene and l-octene.<br>AFRIKAANSE OPSOMMING: Hierdie studie behels die kopolimerisasie van propileen met I-hepteen. Die persentasie van I-hepteen wat as komonomeer in die polimerisasie-reaksies gebruik is, is van 5% tot 20% gevarieer. 'n Verskeidenheid van verskillende kataliste is gebruik vir hierdie polimerisasies. Twee metalloseenkataliste is gebruik: (A) die isospesifieke katalis, rae- [etileen bis(l-indeniel)]zirconium dichloried (rac-Et(lnd)2ZrCh2) en (B) die silileengebrugde katalis, rac-Me2Si(2-MeBenz[e]Ind)2ZrCh2. Metielaluminoksaan (MAO) is as ko-katalis gebruik saam met bogenoemde twee metalloseenkataliste. 'n Ander reeks polimerisasie reaksies is gedoen waarin 'n Ziegler-Natta katalis gebruik is as aktiverende katalis, naamlik TiCi)/ AlEt3/Si02. Die karakterisering van die kopolimere sluit in: hoë temperatuur gel deurlatings chromatrografie (HTGPC) vir molekulêre massa en molekulêre massa verspreidings, differensiële skandering kalorimetrie (DSC) en dinamiese meganiese analisering (DMA) om sodoende die termiese en meganiese eienskappe van die polimere te ondersoek, kern magnetiese resonans spektroskopie (KMR) vir inligting in verband met die mikrostrukture van die kopolimere en kristallisasie analise fraksioneringstegniek (CRYSTAF) om die kort-kettingvertakkings van die kopolimere te ondersoek. Vergelykende studies IS op die verskillende katalisatore en die polimeereienskappe gedoen. Die gesintetiseerde polimere is ook met kopolimere van propileen met I-hekseen en l-okteen vergelyk.

APA, Harvard, Vancouver, ISO, and other styles

35

Carvalho, Soraya Jerico de. "Estudo de novos suportes para catalisadores de ziegler-natta." [s.n.], 1992. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249537.

Full text

Abstract:

Orientador : Ulf Schuchardt<br>Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica<br>Made available in DSpace on 2018-07-15T20:41:19Z (GMT). No. of bitstreams: 1 Carvalho_SorayaJericode_D.pdf: 4481629 bytes, checksum: db970414cb75482f787002b781a8eedc (MD5) Previous issue date: 1992<br>Doutorado

APA, Harvard, Vancouver, ISO, and other styles

36

Meneghetti, Mario Roberto. "Polimerização estereoespecífica do propeno utilizando catalisadores Ziegler-Natta homogêneos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1994. http://hdl.handle.net/10183/25186.

Full text

Abstract:

Foram preparados três tipos de precursores catalíticos homogêneos a base de zirconocênos: os complexos estereorrígidos Et(Ind)2ZrCh 1 e iPrCpFluZrCh 2 contendo simetria C2 e Cs, respectivamente, e o complexo Ind2ZrCh 3. Estes complexos, em presença de metilaluminoxanas (MAO), polimerizam propeno conduzindo a três diferentes tipos de polipropileno. Os complexos estereorrígidos 1 e 2 conduzem a polímeros estereorregulares, iso e sindiotáticos, respectivamente, enquanto o complexo 3 produz polipropileno atático. O grau de estereorregularidade do polímero é dependente da temperatura de polimerização, assim, a baixas temperaturas foram obtidos polímeros altamente estereorregulares, com maiores peso moleculares, Tm eTc. A microestrutura dos polímeros foi determinada por RMN de 13C.<br>We have carried out three different kinds of homogeneous catalyst based on zirconocenes: stereorigid complexes Et(Ind)2ZrCh 1 ,and iPrCpFluZrCb 2 with symmetry C2 e Cs respectively and the complex Ind2ZrCh 3. These complexes together with methylaluminoxane (MAO) can polymerise propene leading to three different kinds of polypropylene. These stereorigid complexes (1 and 2) lead to stereoregular polymers iso and syndiotatic respectively while the complex 3 lead to atatic polypropylene. The polymer stereorigid degree is related with the polymer temperature thus we have obtained high stereoregular polymers with high molecular weight, Tm and Te. The polymers microstructure were obtained by 13C NMR.

APA, Harvard, Vancouver, ISO, and other styles

37

Ziegler, Andrea Susanne [Verfasser]. "Axonale Polyneuropathie bei peripherer arterieller Verschlusskrankheit / Andrea Susanne Ziegler." Ulm : Universität Ulm. Medizinische Fakultät, 2005. http://d-nb.info/1015472087/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Bertrand, Pascale. "Modélisation de la polymérisation de l'éthylène par catalyse Ziegler-Natta." Vandoeuvre-les-Nancy, INPL, 1988. http://www.theses.fr/1988NAN10080.

Full text

Abstract:

Le modèle présenté est fondé sur une approche typique du génie des procédés en ce sens qu'il fait intervenir de pseudo-espèces chimiques représentant le structure du polymère. Les pseudo-espèces chimiques utilisées sont les moments de la distribution des masses moléculaires, le taux de branches courtes, le taux de doubles liaisons et la quantité de polymères produit. Un schéma cinétique faisant intervenir ces espèces est élaboré

APA, Harvard, Vancouver, ISO, and other styles

39

Wolf, Carlos Rodolfo. "Preparação, caracterização e aplicação de catalisadores Ziegler-Natta na produção de polietileno de alta densidade." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/117393.

Full text

Abstract:

Neste trabalho foram sintetizados catalisadores Ziegler-Natta heterogêneos obtidos a partir de TiCl4 e etilato de magnésio com geração de MgCl2 in situ. Foi verificado que o tempo e a temperatura de têmpera da preparação do catalisador influenciam significativamente a atividade catalítica destes. O catalisador não submetido ao processo de têmpera (ZNST), e o catalisador temperado em condições mais rigorosas (ZNT), apresentaram, respectivamente, a maior e a menor atividade catalítica entre vários catalisadores submetidos a diferentes condições de têmpera. Os catalisadores ZNST e ZNT tratam-se de sólidos amorfos, com área superficial e dimensão de partículas semelhantes. Pela análise da composição química dos catalisadores, por diferentes técnicas analíticas, verificouse que o tratamento térmico do catalisador favorece a fixação de TiCl4 e de compostos de Ti oxigenados, diferentes daqueles depositados na reação do MgCl2 com TiCl4. Nesta Tese foi proposta uma estrutura para os sítios ativos formados à base de compostos de Ti oxigenados ou titanoxanos. Estes resultados permitiram a proposição do modelo físico-químico, denominado núcleo-superfície, segundo o qual o catalisador ZNT é constituído de partículas primárias contendo no núcleo predominantemente sítios de Ti do tipo clorotitanatos, entre outros, e na superfície majoritariamente sítios titanoxano (-Ti-O-Ti-). O catalisador ZNST tem majoritariamente sítios de Ti do tipo clorotitanato. O modelo foi válido para explicar o comportamento dos catalisadores na polimerização de eteno, em processo em suspensão, na obtenção do polietileno de alta densidade (PEAD) e também para explicar as propriedades diferenciadas dos polímeros obtidos. O sistema catalítico ZNST-TEA apresentou maior atividade catalítica e produziu o PEAD de menor massa molar e menor polidispersão. Com o sistema catalítico ZNT-IPRA se verificou atividade catalítica intermediária e PEAD com maior massa molar e maior polidispersão.<br>In this work, Ziegler-Natta heterogeneous supported catalysts were synthesized from TiCl4 and magnesium ethylate with MgCl2 in situ generation. It was observed that both catalyst tempering time and temperature influenced significantly the catalytic activity. The non tempered catalyst (ZNST) and the tempered catalyst (ZNT) presented the highest and the lowest catalyst activity, respectively, among other ones prepared in different tempering conditions. The catalysts ZNST and ZNT are amorphous solids and both have approximately the same surface area and particle size. By the catalyst chemical compositions, determined through different techniques, it was possible to conclude that thermal treatment (tempering) increases the Ti content and new oxygenated Ti sites in the catalyst. In this work was proposed a structure to the new site titanoxane different of that one obtained in the MgCl2 chloration of with TiCl4. These results allow proposing a core-shell model. The core of ZNT catalyst particle has mainly Ti site as chloridetitanate, and others, and the shell has primary particles that have mainly titanoxane sites. The ZNST catalyst has mainly Ti sites as chloridetitanate. The model was valid to explain HDPE properties produced by slurry process. The ZNST-TEA catalytic system showed the highest catalytic activity and the HDPE obtained with this system had the lower molecular weight and the lower polidispersity. The ZNT-IPRA catalytic system showed an intermediate activity and the HDPE obtained had the highest molecular weight and broader polidispersity.

APA, Harvard, Vancouver, ISO, and other styles

40

Hohberg, Melanie [Verfasser], Sibylle [Akademischer Betreuer] Ziegler, and PETER [Akademischer Betreuer] BOENI. "Monte Carlo Simulation Studies and Image Reconstruction Methods for a Small Animal PET Scanner / Melanie Hohberg. Gutachter: Sibylle Ziegler ; Peter Böni. Betreuer: Sibylle Ziegler." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/1031511709/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Trinh, Quoc Dung [Verfasser], Felix [Akademischer Betreuer] Ziegler, Felix [Gutachter] Ziegler, and Andrea [Gutachter] Luke. "Operational behaviour and heat transfer in a thermosiphon desorber at sub-atmospheric pressure / Quoc Dung Trinh ; Gutachter: Felix Ziegler, Andrea Luke ; Betreuer: Felix Ziegler." Berlin : Technische Universität Berlin, 2016. http://d-nb.info/1156186889/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Auer, Daniela. "Das Spanienbild in den Reiseberichten der Mitte des 19. Jahrhunderts am Beispiel von Wilhelm zu Löwenstein und Alexander Ziegler /." kostenfrei, 2008. http://othes.univie.ac.at/1933/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Lima, Raimundo Nonato Teixeira. "Estudo da pré-polimerização do catalisador Ziegler-Natta em uma planta comercial de produção de polietileno." Universidade Federal da Bahia. Escola Politécnica, 2013. http://repositorio.ufba.br/ri/handle/ri/18601.

Full text

Abstract:

Submitted by LIVIA FREITAS (livia.freitas@ufba.br) on 2016-02-11T18:37:21Z No. of bitstreams: 1 DISSERTAÇÃO CORREÇÕES.doc: 21344768 bytes, checksum: b95655c72f702ef0dc100285e5eb726e (MD5)<br>Approved for entry into archive by Uillis de Assis Santos (uillis.assis@ufba.br) on 2016-02-12T14:13:24Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO CORREÇÕES.doc: 21344768 bytes, checksum: b95655c72f702ef0dc100285e5eb726e (MD5)<br>Made available in DSpace on 2016-02-12T14:13:24Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO CORREÇÕES.doc: 21344768 bytes, checksum: b95655c72f702ef0dc100285e5eb726e (MD5)<br>Atualmente o polietileno é o termoplástico mais produzido em todo o mundo, seguido do polipropileno e do policloreto de vinila (PVC). A polimerização de eteno com o uso de um dado catalisador heterogêneo apresenta o fenômeno da fragmentação do mesmo, independentemente do processo e/ou tecnologia comercial empregada. O fenômeno de fragmentação do catalisador dependente principalmente das propriedades do suporte, do sistema catalítico utilizado, das propriedades do polímero e das condições do reator. Quando a fragmentação do catalisador ocorre de forma adequada, ela leva a uma maior exposição dos sítios ativos, facilitando assim o acesso do monômero à partícula do catalisador com, consequente aumento da taxa de polimerização. No entanto, caso a fragmentação não seja devidamente controlada pode ocasionar a formação de partículas muito pequenas (finos) e com morfologia irregular, podendo levar também a uma redução da taxa de polimerização. Este trabalho tem como objetivo estudar o fenômeno de fragmentação durante a etapa de pré-polimerização do catalisador Ziegler-Natta na unidade de produção de polietilenos da Braskem PE 2 BA. Foi possível determinar as características morfológicas e texturais do catalisador Ziegler-Natta não polimerizado e na forma pré-polimerizado, avaliar a eficiência catalítica na reação de polimerização do eteno, utilizando uma planta de bancada, além de estudar a estrutura do polímero final. Foram realizadas caracterizações das amostras por MEV, EDS, difração de raio laser e análise granulométrica. Os resultados destas análises apontaram para uma diferença significativa entre a amostra do catalisador B e as demais amostras. Esta diferença observada pode ser explicada pela morfologia irregular do catalisador B na sua forma reduzida, além da baixa porosidade da partícula na forma pré-polimerizada. Propriedades que são devidas a uma possível menor fragmentação do seu suporte, levando a um maior recobrimento da partícula do catalisador reduzido com polímero, sem ocorrer à quebra do seu suporte, contribuindo somente para o aumento do tamanho da partícula. O estudo desenvolvido permitiu o entendimento das alterações provocadas na morfologia da partícula do catalisador reduzido durante a pré-polimerização e o seu impacto durante reação de polimerização do eteno, além de avaliar as consequências na morfologia do polímero final.

APA, Harvard, Vancouver, ISO, and other styles

44

Ziegler, Lee. "Tests of distributional assumptions and the informational content of agricultural futures options." Thesis, Montana State University, 1997. http://etd.lib.montana.edu/etd/1997/ziegler/ZieglerL1997.pdf.

Full text

Abstract:

It has been proposed that agricultural futures options contain information which may be used by those involved in agriculture, such as rate setting for crop (revenue) insurance. Specifically, it is proposed that these options may be used to predict the variance and perhaps higher moments of the distribution of the respective futures prices. This thesis first tests distributional assumptions maintained by the Black-Scholes analysis. It is found that many of these assumptions, such as the commonly used lognormality, are empirically rejected. Furthermore, it is found that futures price change standard deviations and futures options implied volatilities display seasonal patterns. Second, this thesis tests whether com, soybean, and spring wheat futures options implied volatilities obtained from the Black formula are accurate predictors of futures price variance. Empirically, these implied volatilities are found to be very poor predictors of subsequent futures price variance. Furthermore, there is no empirical support to show that the agricultural futures options market has become more efficient since it first started trading in the mid-1980's.

APA, Harvard, Vancouver, ISO, and other styles

45

Ziegler, Elvira [Verfasser]. "Histologische Veränderungen nach verschiedenen Blutentnahmemethoden bei der Maus / Elvira Ziegler." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1031115595/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Ziegler, Stephanie Martha [Verfasser]. "Polymerzerstäubung als Herstellungsverfahren individualisierbarer Gefäßprothesen für Kunstherzen / Stephanie Martha Ziegler." Aachen : Shaker, 2018. http://d-nb.info/1188550128/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Ziegler, Diana [Verfasser]. "Zeichen setzen und Zeichen verstehen: Alltagsästhetik und Werbung / Diana Ziegler." Aachen : Shaker, 2008. http://d-nb.info/1164342347/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Ziegler, Wolfgang [Verfasser]. "Die Verkündung von Satzungen und Rechtsverordnungen der Gemeinden. / Wolfgang Ziegler." Berlin : Duncker & Humblot, 2019. http://d-nb.info/1237962072/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Bierwagen, Erik Paul Goddard William A. Goddard William A. "Computational studies of Ziegler-Natta catalysis and concurrent resonance computations /." Diss., Pasadena, Calif. : California Institute of Technology, 1995. http://resolver.caltech.edu/CaltechETD:etd-09112007-104050.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Hajela, Sharad Bercaw John E. "Synthetic, structural, and mechanistic studies of homogeneous Ziegler-Natta catalysis /." Diss., Pasadena, Calif. : California Institute of Technology, 1995. http://resolver.caltech.edu/CaltechETD:etd-10052007-131102.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!