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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

Incorporation of 4d and 5d Transition Metal Cyanometallates into Magnetic Clusters and Materials.

Hilfiger, Matthew Gary 2010 May 1900 (has links)
The work presented herein describes efforts to synthesize and characterize new types of cyanide-bridged molecular materials encompassing both discrete clusters and extended solids. This investigation focused on the incorporation of anisotropic 4d and 5d transition metal ion building blocks into such materials. In this vein, systematic studies on the magnetic properties of families of these cyano-bridges species were conducted and these new materials represent a new addition to the field of cyanide chemistry incorporating for the first time the hexacyanometallates of [Ru(CN)6]3- and [Os(CN)6]3- into discrete molecules and extended networks. These compounds will serve as models for new theoretical studies in understanding the role of magnetic exchange interactions, both isotropic and anisotropic, in the study of nanomagnetic materials. Results were obtained from using the well known octacyanometallates of MoV and WV as building blocks for the synthesis and the magnetic investigation of both trigonal bipyramidal and pentadecanuclear clusters including the discovery of a new SMM. By expanding the research to previously unused hexacyanometallates, the synthesis and characterization of the first known examples of clusters based on hexacyanoosmate(III) and hexacyanoruthenate(III) building blocks and their use in preparing new theoretical models of magnetic species. A novel pair of clusters is further detailed in the study of the trigonal bipyramidal clusters of [Fe(tmphen)2]3[Os(CN)6]2 and [Fe(tmphen)2]3[Ru(CN)6]2 and an in depth study of the CTIST behavior of these clusters using Mossbauer spectroscopy, variable temperature crystallography, epr, and variable temperature IR measurements. Finally, this work discusses new magnetic Prussian Blue analogs prepared from the hexacyanoosmate(III) and hexacyanoruthenate(III) anions with a comparison to the trigonal bipyramidal clusters presented based on these hexacyanoosmate(III) and hexacyanoruthenate(III) building blocks.
42

A computational approach to study the effect of multiple lymphangion coordination on lymph flow

Madabushi Venugopal, Arun 01 November 2005 (has links)
The lymphatic system acts to return fluid from the interstitial space back into the blood circulation. In normal conditions, lymphangions, the segment of lymphatic vessel in between valves, cyclically contract and can pump lymph from low pressure tissues to the higher-pressure veins of the neck. With edema, however, this pressure gradient can reverse, and the role of contraction is less clear. Like ventricles, lymphangions are sensitive to both preload and afterload. Unlike ventricles, lymphangions are arranged in series, so that the outlet pressure of one lymphangion becomes the inlet pressure of another. Anything that alters the relative timing and frequency of adjacent lymphangions alters both preload and afterload of each lymphangion and thus mean lymph flow. To explore the effect of timing and frequency of contraction on lymph flow, we developed a computational model of a lymphatic vessel with lymphangions described by the classic description of time-varying elastance. When pumping up a pressure gradient, as in normal conditions, or when pumping down a pressure gradient, as in some cases of edema, we found that flow was optimized when the lymphangions in the vessel were pumping with a very short time delay between their cycles, and the flow was reduced when the time delay between the contractions was reduced to zero. However, a difference in frequency between adjacent lymphangions alters instantaneous flow but does not affect mean flow. These results suggest an important role for the timing of the contraction in optimizing lymph flow. However, a difference in frequencies between adjacent lymphangions has little effect on altering lymph flow, suggesting that tight control of lymphangion coordination may not be critical for lymphatic function.
43

Kinematic errors in a reach task with dissociated eye and hand movement /

Ma, Xiaomu. January 2006 (has links)
Thesis (M.Sc.)--York University, 2006. Graduate Programme in Kinesology and Health Science. / Typescript. Includes bibliographical references (leaves 41-44). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR29580
44

What makes fustion cells effective?

Fussell, Christopher L. Hough, Trevor W. Pedersen, Matthew D. January 2009 (has links) (PDF)
Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Arquilla, John. Second Reader: Hocevar, Susan P. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Fusion center, fusion cell, interagency fusion, interagency reform. Includes bibliographical references (p. 117-120). Also available in print.
45

Crystal structure of co-ordination compounds.

Cheung, Kung-kai. January 1962 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1963. / Type-written copy. Includes bibliographical references (leaves 102-104).
46

Synthesis and post-synthetic modifications of novel carboxylated triphenylphosphine-based coordination polymers

Nuñez, Ana Julia 03 September 2015 (has links)
Over the last few decades, Porous Coordination Polymers (PCPs, a.k.a. MOFs) have been extensively studied for a number of applications due to their functional and structural versatility. Nonetheless, systematic studies that explore the structure-function relationship of frameworks decorated with different functional groups remain limited. In the present work, two families of coordination polymers that contain organophosphine building blocks have been synthesized and characterized. These materials contain a periodic array of P(III) Lewis base sites that are available for post-synthetic functionalization. PCM-10 is a porous coordination polymer based on Ca(II) and tris(p-carboxylated) triphenylphosphine. The material displayed a 3-dimensional surface, ideal for a series of post-synthetic modifications. The versatility of P(III)→P(V) chemistry allowed for decoration of the R₃P: sites of PCM-10 with different functional groups. Solid-state treatment of the framework with a variety of precursors, gave rise to a family of isostructural materials (ClAu-PCM-10, O=PCM-10 and (Me‒PCM-10)X; X = I⁻, F⁻, BF₄⁻ and PF₆⁻). These post-synthetic modifications directly affected the host-guest interactions, as demonstrated by comparative adsorption studied of CO₂, H₂ and other small molecules. For example, the phosphonium (Me-PCM-10)X composites displayed broad tunability of isosteric heats of CO₂ adsorption, depending on the counter-ion. Similarly, the ClAu-PCM-10 derivative resulted in selective adsorption of 1-hexene vs. n-hexane and displayed significantly increased H₂ uptake capacity, when compared to PCM-10. Ln-PCM-22 is a family of isostructural PCPs based on tris(p-carboxylated) triphenylphosphine and Ln(III) (Ln = Sm-Yb). Photoluminescence studies of Eu-PCM-22 and Tb-PCM-22 were used to elucidate certain aspects of the solid-state emissive properties of phosphine-based materials. In addition, a single-crystal-to-single-crystal post-synthetic oxidation of Tb-PCM-22 was achieved to yield the composite material Tb-O=PCM-22. This modification resulted in enhancement of the quantum efficiency, compared to that of the parent framework. These results will help further the understanding of PCMs and direct the upcoming synthesis and application of these materials. / text
47

New approaches to nitrogen ligands bearing electron withdrawing groups and their role in coordination chemistry

Shukla, Piyush, 1977- 27 July 2011 (has links)
Not available / text
48

STRUCTURE AND BEHAVIOR OF SOME SUBSTITUTED 8-QUINOLINOLS

Stevenson, Robert Lovell January 1967 (has links)
No description available.
49

Yaqui Coordination

Martínez-Fabián, Constantino January 2005 (has links)
This research describes and explains in the OT framework the Yaqui coordination. It is assumed that coordinate structures are asymmetric and, based in the Yaqui data, I propose that the coordination is the result of an adjunct-host relation. This work shows that the ConjP is inappropriate for explaining the place that the Yaqui coordinator into 'and' occupies in overt syntax. It demonstrates that the proposal which suggests that coordinators in second position are clitics (Agbayani and Goldston 2002) can not be maintained in Yaqui because such position is generated by fronting a topicalized constituent. If we depart from the idea that clitics and topics move to different positions, then a different explanation is required. The proposal is extended to the analysis of unbalanced verbal chaining structures. It is shown that some --kai constructions are marked syntactically as subordinated but actually they are coordinate structures. In the final part of this work I describe and analyze the agreement between coordinate nominals and verbs. The analysis indicates that Yaqui responds partially to the system of CONCORD and INDEX features proposed by Halloway King and Dalrymple (2004). However, its whole explanation requires the use of constraints in order to explain the coordinate patterns of the language.
50

Movement coordination and control in children with and without Developmental Coordination Disorder in ball catching

Przysucha, Eryk Unknown Date
No description available.

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