• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 137
  • 35
  • 25
  • 16
  • 5
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 348
  • 348
  • 100
  • 83
  • 52
  • 39
  • 38
  • 35
  • 35
  • 33
  • 30
  • 29
  • 26
  • 26
  • 26
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Studies of molecular cluster ions

Jarvis, Vern Marshall 08 1900 (has links)
No description available.
102

Effects of molecular shape on the structure of alkane mixtures

Tra, Van-Huu. January 1982 (has links)
Using the new Picker flow calorimeter, the excess heat capacity (C(,p)('E)) has been measured for systems containing normal, branched and cyclic alkanes. The results indicate two unusual effects: (1) a large negative contribution due to the destruction of orientational order in a pure n-alkane component, and (2) a positive contribution attributed to the "condensation" of a more freely-moving molecule or segment on a sterically-hindered branched alkane, resulting in a restriction of rotational movement, i.e. creation of order in the solution. Mixtures of cycloalkanes and their methyl derivatives also show unexpected positive effects in the excess heat capacity. Thus the plate-like cyclopentane molecule gives positive C(,p)('E) values when mixed with other plate-like methyl derivatives of cyclohexane suggesting a hindering of its molecular rotation. / Cyclohexane mixed with globular branched and cyclic alkanes shows S-shaped C(,p)('E) curves, negative at low concentration of cyclohexane but positive at high, indicating the possibility of a restriction of cyclohexane motion. / Effects of order are also apparent in the equation of state of a liquid. The thermal pressure coefficient for systems containing n-hexadecane has been found to be anomalous and is explained by a lowering of the internal energy of n-hexadecane by orientational order. / Excess volume (V('E)) has been studied for systems of branched and normal alkanes by investigating different effects contributing to the total V('E), particularly an important effect of a difference in thermal pressure coefficients of the two components.
103

Design, synthesis and characterization of bio/electroactive hybrids confining chromophores in dilute solutions using a helical peptide template /

Kas, Onur Y. January 2008 (has links)
Thesis (Ph. D.)--University of Delaware, 2007. / Principal faculty advisor: Mary E. Galvin-Donoghue, Dept. of Materials Science & Engineering. Includes bibliographical references.
104

The coordination of nickel in hyperaccumulating plants /

Callahan, Damien Lee. January 2007 (has links)
Thesis (Ph.D.)--University of Melbourne, School of Chemistry, 2007. / Typescript. Includes bibliographical references (leaves 151-169).
105

Molecular aspects of biomolecule structure and function

Rodger, Alison. January 2002 (has links)
Thesis (D. Sc.)--University of Sydney, 2003. / Title from title screen (viewed Apr. 28, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Science to the School of Chemistry, Faculty of Science. Degree awarded 2003; thesis submitted 2002. Includes bibliographical references. Also available in print form.
106

Density functional theory studies of selected hydrogen bond assisted chemical reactions

Guo, Zhen, January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leave 94-102). Also available in print.
107

Photoionization of organic molecules in MCM-41, AlMCM-41 and metal containing AlMCM-41 mesoporous materials

Sinlapadech, Sunsanee. January 2003 (has links)
Thesis (Ph.D.)--University of Houston, 2003. / Adviser: Allan J. Jacobson. Includes bibliographical references.
108

Highly sensitive and efficient infrared spectroscopy of molecular ions /

Lindsay, C. Michael. January 2002 (has links)
Thesis (Ph. D.)--University of Chicago, Department of Chemistry, June 2002. / Includes bibliographical references. Also available on the Internet.
109

High resolution infrared laser spectroscopy of CH[subscript 5 superscript +] /

White, Edmund Thomas. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Chemistry, August 1999. / Includes bibliographical references. Also available on the Internet.
110

Dissociação de partículas num potencial rugoso sob a ação de perturbação dependente do tempo /

Forlevesi, Murilo Deliberali. January 2017 (has links)
Orientador: Ricardo Egydio de Carvalho / Banca: Emanuel Fernandes de Lima / Banca: Luiz Antônio Barreiro / Resumo: O objetivo deste trabalho é estudar a dinâmica e o controle da fotodissociação de uma molécula diatômica submetida a um potencial rugoso, o qual é aplicado em diversas áreas da ciência para modelar processos naturais, através da introdução de uma perturbação dependente do tempo e de um termo dissipativo. O estudo faz uma análise inicial das alterações que ocorrem na dinâmica de uma molécula submetida ao potencial de Morse rugoso, em seguida o sistema é perturbado através da introdução de um campo elétrico, é mostrado um estudo no potencial sem a rugosidade que consiste na criação de um mecanismo para gerar trajetórias estáveis em regiões de transição de energia, faz-se uma aplicação deste resultado visando o controle do processo de fotoassociação. Para o potencial de Morse rugoso forçado estuda-se a dinâmica do sistema, a qual revela o aparecimento de novas regiões de estabilidade na vizinhança do mínimo de potencial, a probabilidade de fotodissociação molecular para este sistema é analisada com ênfase no controle dos parâmetros (constantes do termo rugoso). Por fim introduz-se a dissipação e é feito um estudo da convergência das diversas condições iniciais para regiões específicas do espaço de fase o que mostra que a rugosidade pode ser utilizada como um mecanismo de atração de trajetórias / Abstract: The objective of this work is to study the dynamics and the control of the photodiscitation of a molecule submitted to a rough potential, which has been shown to be applied in diverse areas of science to model natural processes, through the introduction of a time and time dependent perturbation Dissipative. The study makes an initial analysis of the changes that occur in the dynamics of a molecule subjected to the rough Morse potential, then the system is disturbed by the introduction of an electric field, a study is shown in the potential without the roughness consisting in the creation of A mechanism to generate stable trajectories in regions of energy transition is made an application of this result aiming the control of the photoassociation process. For the forced roughness morse potential, we study the dynamics of the system, which reveals the appearance of new stability regions in the vicinity of the minimum potential, the probability of molecular photodissociation for this system is analyzed with emphasis on the control of the parameters Of the rough term). Finally the dissipation is introduced and an analysis is made of the convergence of the various initial conditions for specific regions of the phase space which shows that the roughness can be used with a trajectory attraction mechanism / Mestre

Page generated in 0.238 seconds