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  • 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.
41

Supramolecular assembly with silver(1) aggregates containing encapsulated acetylenediide and ancillary ligands. / CUHK electronic theses & dissertations collection

January 2005 (has links)
Zhao Xiaoli. / "July 2005." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 178-194). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese.
42

Supramolecular architecture of multi-dimensional frameworks in crystalline adducts of hexamethylenetetramine with hexacyanoferrates and metal pseudohalides.

January 1996 (has links)
by Feng Xue. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 76-84). / ACKNOWLEDGMENTS --- p.I / ABSTRACT --- p.II / TABLE OF CONTENTS --- p.III / LIST OF TABLES --- p.V / LIST OF FIGURES --- p.VI / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter 1. --- supramolecular chemistry --- p.1 / Chapter 2. --- Infinite multi-dimensional architecture --- p.10 / Chapter 3. --- Chemistry of pseudohalides --- p.15 / Chapter 4. --- Chemistry of hexamethylenetetramine --- p.20 / Chapter 5. --- Objectives of the present research --- p.24 / Chapter CHAPTER 2: --- EXPERIMENTAL --- p.25 / Chapter 1. --- Preparation --- p.25 / Chapter 1.1 --- Materials --- p.25 / Chapter 1.2 --- Preparation of the compounds --- p.25 / Chapter 2. --- X-ray crystallography --- p.26 / Chapter CHAPTER 3: --- DESCRIPTION OF CRYSTAL STRUCTURES --- p.28 / Chapter 1. --- isostructural compounds K2[FEII(CN)6] ´Ø 2[(CH2)6n4H] ´Ø 4H2 O(1) and K2[FEIII(CN)6] ´Ø [(CH2)6N4H] ´Ø [(CH2)6N4] ´Ø 4H2O (2) --- p.28 / Chapter 2. --- Crystal structure of NA2[FEIII(CN)6] ´Ø [(CH2)6N4H] ´Ø [(CH2)6N4] ´Ø 5H2O (3) --- p.33 / Chapter 3. --- Crystal structure of K3[FEIII(CN)6] ´Ø 2[(CH2)6N4] ´Ø 4H2O (4) --- p.37 / Chapter 4. --- Crystal Structure of ferricyanic acid-HMT adduct H3[FEIII(CN)6] ´Ø 2[(CH2)6N4] ´Ø 2H2O (5) --- p.43 / Chapter 5. --- "Crystal structure of cadmium chloride-HMT adduct, Cd2[C6H12N4H2]Cl6´Ø 3H2O (6)" --- p.48 / Chapter 6. --- "Crystal structure of cadmium bromide-HMT adduct, CdBr2 ´Ø 2[(CH2)6N4] ´Ø 2H2O (7)" --- p.53 / Chapter 7. --- "Crystal structure of cadmium iodide-HMT adduct, 3CdI2 ´Ø 2[(CH2)6N4] ´Ø 4H2O (8)" --- p.57 / Chapter 8. --- Crystal structure of cadmium thiocyanate-HMT adduct Cd(SCN)2 ´Ø 1(CH2)6N4] ´Ø MeOH (9) --- p.61 / Chapter 9. --- Crystal structure of cobalt cyanate-HMT adduct Co(NCO)2 ´Ø [(CH2)6N4] ´Ø 2H2O (10) --- p.67 / Chapter CHAPTER 4: --- SUMMARY AND DISCUSSIONS --- p.72 / REFERENCES --- p.76 / TABLE A1 Crystallographic data for compounds 1 ~5 --- p.85 / TABLE A2 Crystallographic data for compounds 6~10 --- p.86 / APPENDIX 1 Atomic Coordinates (Ax 104) and Equivalent Isotropic Thermal Parameters (A 2x103) --- p.87 / APPENDIX 2 Anisotropic thermal parameters (A2x 103) --- p.92 / APPENDIX 3 H-atom coordinates (x 104) and isotropic thermal parameters (A2x 103) --- p.96
43

Improving the methods of macromolecular structure determination

Korostelev, Andrei. Chapman, Michael S., January 2003 (has links)
Thesis (Ph. D.)--Florida State University, 2003. / Advisor: Dr. Michael S. Chapman, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Feb. 24, 2003). Includes bibliographical references.
44

Biodegradation of model macromolecules (proteins and polysaccharides) in wastewaters

Confer, David Ray, 1956- January 1996 (has links)
Macromolecules such as proteins and polysaccharides can constitute a significant portion of dissolved organic carbon (DOC) in wastewater, but limited information is available on how these compounds are degraded in biological wastewater treatment systems. Bacteria cannot assimilate intact macromolecules but must first hydrolyze them to monomers or small oligomers. To better understand the mechanism of macromolecule degradation in wastewater treatment systems this study investigates two important questions of macromolecule metabolism. First, does hydrolysis occur in close proximity to the cell or are the hydrolytic enzymes released into bulk solution, and second, if hydrolysis is cell-associated, are hydrolyzed fragments directly assimilated into the cell or are they released back into solution? Fluorescent model substrate analogs were used to determine the location of leucine aminopeptidase and a-glucosidase activity in wastewater inoculated biofilm and suspended cultures and in trickling filter effluent. In biofilm and suspended cultures at least 93% of hydrolytic activity was cell-associated. In trickling filter effluent hydrolysis rates were at least five times higher in contact with cells and sloughed biofilm pieces than in cell-free solution. To determine whether hydrolytic fragments were directly assimilated or released into solution molecular size distributions in bulk solution were monitored using membrane ultrafiltration techniques during the degradation of the model protein, bovine serum albumin, and the model polysaccharides, dextran and dextrin, in batch and continuous suspended cultures, and in fixed-film reactor systems. Measurable amounts of macromolecule hydrolytic fragments accumulated in all reactor configurations, substrates and inocula tested. Relatively larger concentrations of hydrolytic fragments accumulated in pure culture than in wastewater culture inoculated reactors. These results support a generalized model for macromolecule degradation by bacteria that features cellbound hydrolysis of protein and polysaccharides and the subsequent release of hydrolytic fragments back into bulk solution. This hydrolysis and release is repeated until fragments are small enough ( < 1000 amu) to be assimilated by cells. A separate, but related, part of this study adapted pre-column orthophthaldialdehyde derivatization, reverse phase high performance liquid chromatographic separation and fluorometric detection to measure free and combined amino acids in unconcentrated wastewaters and to assess their treatability in wastewater treatment systems.
45

The application of Brillouin spectroscopy to solutions of macromolecules and inorganic complexes

San Filippo, Frank Ignatius 08 1900 (has links)
No description available.
46

Phosphorescence anisotropy and triplet-triplet energy transfer : probes of dynamics and structure in biological macromolecules

Strambini, Giovanni Battista. January 1975 (has links)
No description available.
47

Synthesis and molecular control of star-like poly-2,4-benzoxazole

Park, Joonwon January 1992 (has links)
No description available.
48

Oligomeric tetrathiafulvalenes in supramolecular chemistry

Devonport, Wayne January 1995 (has links)
A range of highly ordered dendritic and oligomeric macromolecules, functionalised with tetrathiafulvalene (TTF) derivatives as a redox-active sub-unit were assembled. In particular, the first dendritic macromolecules incorporating TTF were constructed by the reaction of poly-acid chlorides and alcohol functionalities. Electrochemical techniques showed the novel redox-superstructures to be efficient π-electron donors that are able to undergo two reversible, multi-electron-on oxidations. The TTF-units were established to be acting independently, and the extent to which the redox groups could be oxidised was evaluated. UV studies demonstrated the redox- assemblies to be capable of forming charge-transfer complexes m solution and showed potential for the formation of conducting charge-transfer complexes. Preliminary studies showed the precursors to these compounds to be suitable for use as electrochemical detectors for dopamine. Structural variation of the core units increased the air and thermal stability of the dendritic materials, whilst retaining the characteristics of the multi-redox system. These systems formed stable aggregates of the radical cation and afforded conducting charge- transfer complexes with TCNQ. The new precursors to multi-TTF systems were then used in attempts to impart redox characteristics on [2]pseudorotaxanes and rotaxanes. Preliminary attempts were made to assemble multi-TTF systems using a TTF derivative as a core and at the periphery.
49

Magnetic protein cages characterized by electron magnetic resonance spectroscopy

Usselman Jr., Robert John. January 2005 (has links) (PDF)
Thesis (Ph.D.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: David J. Singel. Includes bibliographical references (leaves 124-133).
50

Structural characterization of complex polymer systems by degradation/mass spectrometry

Thomya, Panthida. January 2006 (has links)
Thesis (Ph. D.)--University of Akron, Dept. of Chemistry, 2006. / "December, 2006." Title from electronic dissertation title page (viewed 04/24/2008). Advisor, Chrys Wesdemiotis; Committee members, Matthew P. Espe, Jun Hu, Wiley J. Youngs, Frank W. Harris; Department Chair, Kim C. Calvo; Dean of the College, Ronald F. Levant; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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