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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.
241

Reactions of cellulose in the dimethyl sulfoxide/paraformaldehyde (DMSO/PF) solvent

Nicholson, Myron Donal, January 1976 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1976. / Includes bibliographical references (p. 80-83).
242

Study of photoinduced electron transfer reactions and effect of solvent interactions on the photophysical and photochemical propertiesof dinuclear Au(I), polynuclear Cu(I) and cyclometallated Pt(II)complexes

陳國柱, Chan, Kwok-chu. January 1999 (has links)
published_or_final_version / abstract / toc / Chemistry / Doctoral / Doctor of Philosophy
243

Studies on the growth, dissolution and equilibrium solubility of barium, lead and radium sulfates in aqueous sulfate media: With applications to the sulfuric acid leaching process for uranium milling.

Paige, Christopher Robin. Hileman Jr., O. E. Unknown Date (has links)
Thesis (Ph. D.)--McMaster University (Canada), 1990. / Source: Dissertation Abstracts International, Volume: 52-10, Section: B, page: 5258. Supervisor: O.E. Hileman, Jr.
244

The alpha-hydroxyalkyl diazenes and the alpha-hydroperoxyalkyl diazenes as sources of radicals for the kinetic studies of some radical-molecule reactions in solution.

Mathew, Lukose K. Warkentink, John. Unknown Date (has links)
Thesis (Ph.D.)--McMaster University (Canada), 1991. / Source: Dissertation Abstracts International, Volume: 53-01, Section: B, page: 0308. Supervisor: John Warkentin.
245

Study of photoinduced electron transfer reactions and effect of solvent interactions on the photophysical and photochemical properties of dinuclear Au(I), polynuclear Cu(I) and cyclometallated Pt(II) complexes /

Chan, Kwok-chu. January 1999 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references.
246

Terahertz spectroscopy of the intermolecular and intramolecular vibrations of molecules in solution

Fedor, Anna M. January 2007 (has links)
Thesis (Ph. D.)--Syracuse University, 2007. / "Publication number: AAT 3295517."
247

The stability of some molecular complexes in aqueous mixed solvents correlation with solvent surface tension.

Sun, Sy-rong. January 1971 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
248

Ensino de soluções químicas por meio da abordagem Ciência-Tecnologia-Sociedade (CTS)

Niezer, Tânia Mara 24 August 2012 (has links)
Este estudo parte da problematização sobre as possibilidades de se ensinar em sala de aula, o conteúdo químico de Soluções, relacionado ao cotidiano dos alunos, de forma a proporcionar a Alfabetização Científica e Tecnológica (ACT) por meio do enfoque Ciência-Tecnologia-Sociedade (CTS). O objetivo geral desta pesquisa consiste em desenvolver e analisar o ensino do conteúdo químico Soluções relacionando-o ao cotidiano dos alunos por meio do enfoque CTS contribuindo para a Alfabetização Científica e Tecnológica (ACT). O estudo foi desenvolvido com 55 alunos, da 2ª série do Ensino Médio, do curso Técnico em Agropecuária de um Centro Estadual de Educação Profissional, da cidade de Rio Negro, no Paraná. A abordagem metodológica foi a qualitativa de natureza interpretativa, com observação participante. A coleta de dados se deu por meio de fotos e vídeos das atividades, observação das próprias atividades realizadas pelos alunos, arguições orais, relatórios e anotações em diário de campo. As atividades desenvolvidas nesta pesquisa foram organizadas em quinze (15) momentos, nos quais se buscou discutir e contextualizar as relações sociais da Ciência e da Tecnologia por meio do estudo de Soluções químicas, de forma interdisciplinar. Os principais resultados evidenciaram que o enfoque CTS no ensino de Soluções, contribuiu para a apropriação dos conceitos químicos, pelos alunos, sendo possível transpor questões que os envolvem dia a dia. No decorrer das aulas os alunos se mostraram mais críticos e reflexivos acerca das implicações sociais em relação às questões científicas e tecnológicas. Outro resultado obtido neste estudo consistiu na elaboração de um guia didático, que poderá ser utilizado como sugestão metodológica pelos professores de Química do Ensino Médio. / This study is the questioning about the possibilities of teaching in the classroom, the chemical content of solutions, related to the daily life of students, to provide the Scientific and Technological Literacy (ACT) by focusing Science-Technology-Society (CTS). The overall goal of this research is to develop and analyze the chemical content of education solutions relating to the daily lives of students by focusing CTS contributing to the Scientific and Technological Literacy (ACT). The study was conducted with 55 students from 2nd grade of high school, the course of an Agricultural Technician in State Center for Professional Education, the city of Rio Negro, Parana. The methodological approach was qualitative interpretative, with participant observation. Data collection occurred through photos and videos of activities, observation of activities performed by the students themselves, Pleas oral reports and notes in a field journal. The activities developed in this research were organized into fifteen (15) times in which it was sought to discuss and contextualize the social relations of science and technology through the study of chemical solutions, in an interdisciplinary way. The main results showed that the CTS approach in teaching Solutions, contributed to the appropriation of chemical concepts, students, and can transpose issues that involve day to day. During the classes students were more critical and reflective about the social implications in relation to science and technology issues. Another result obtained in this study consisted of developing a teaching guide that can be used as a methodological suggestion by teachers of high school chemistry.
249

Synthesis of transition metal oxides and hydroxides by soft-chemistry routes.

January 2009 (has links)
Chan, Mui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references. / Abstract also in Chinese. / Abstract --- p.i / Abstract (Chinese) --- p.iii / Declaration --- p.v / Acknowledgement --- p.vi / Table of Contents --- p.viii / List of Tables --- p.xiv / List of Figures --- p.xv / Chapter Chapter 1: --- Introduction / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Soft-Chemistry --- p.7 / Chapter 1.2.1 --- Sol-Gel Method --- p.7 / Chapter 1.2.2 --- Co-precipitation --- p.9 / Chapter 1.2.3 --- Microemulsion --- p.10 / Chapter 1.3 --- Application of Hydrothermal/Solvothermal Methods in Materials Synthesis --- p.12 / Chapter 1.3.1 --- Fundamentals of Hydrothermal and Solvothermal Methods --- p.12 / Chapter 1.3.2 --- Advantages of Hydrothermal/Solvothermal Methods in contrast to Conventional Synthetic Approaches --- p.13 / Chapter 1.3.3 --- Hydrothermal and Solvothermal Preparation of Materials --- p.14 / Chapter 1.4 --- Application of Transition Metal Oxides As Functional Materials --- p.15 / Chapter 1.5 --- Aim and Scope of Work --- p.16 / Chapter 1.6 --- References --- p.17 / Chapter Chapter 2: --- Solvothermal and Hydrothermal Template Free Synthesis of ZnO Microspheres / Chapter 2.1 --- Introduction --- p.23 / Chapter 2.2 --- Experimental Section --- p.25 / Chapter 2.2.1 --- Synthesis of ZnO Microspheres by Solvothermal Method --- p.25 / Chapter 2.2.2 --- Synthesis of ZnO Microspheres by Hydrothermal Method --- p.26 / Chapter 2.2.3 --- Doping ZnO Microspheres with Silver or Gallium by Solvothermal Method --- p.26 / Chapter 2.2.4 --- Characterization --- p.27 / Chapter 2.2.5 --- Measurement of Photocatalytic Activity --- p.29 / Chapter 2.3 --- Results and Discussion --- p.30 / Chapter 2.3.1 --- X-Ray Diffraction Analysis --- p.30 / Chapter 2.3.1.1 --- ZnO-HT and ZnO-ST --- p.30 / Chapter 2.3.1.2 --- ZnO-ST: Effect of Different Concentrations of Zinc Acetate --- p.33 / Chapter 2.3.1.3 --- Doping ZnO-ST with Silver or Gallium --- p.34 / Chapter 2.3.2 --- SEM study --- p.36 / Chapter 2.3.2.1 --- ZnO-HT and ZnO-ST --- p.36 / Chapter 2.3.2.2 --- ZnO-HT-Different Volume Ratios of Ethylene Glycol to Water --- p.37 / Chapter 2.3.2.3 --- ZnO-ST --- p.39 / Chapter 2.3.2.3.1 --- Different Volume Ratios of Benzyl Alcohol to Ethylene Glycol --- p.40 / Chapter 2.3.2.3.2 --- Different Concentrations of Zinc Acetate --- p.41 / Chapter 2.3.2.3.3 --- Different Concentrations of Urea --- p.42 / Chapter 2.3.3 --- TEM Study --- p.44 / Chapter 2.3.3.1 --- TEM and HRTEM of ZnO-HT --- p.44 / Chapter 2.3.3.2 --- TEM and HRTEM of ZnO-ST --- p.45 / Chapter 2.3.3.3 --- TEM Images of Ga-Doped ZnO-ST --- p.47 / Chapter 2.3.3.4 --- TEM Images of Ag-Doped ZnO-ST --- p.49 / Chapter 2.3.4 --- Nitrogen Adsorption and Desorption --- p.50 / Chapter 2.3.5 --- X-Ray Photoelectron Spectroscopy --- p.52 / Chapter 2.3.5.1 --- XPS Study of ZnO-ST --- p.52 / Chapter 2.3.5.2 --- XPS Study of ZnO-HT --- p.54 / Chapter 2.3.5.3 --- XPS Study of Silver Doped ZnO-ST --- p.56 / Chapter 2.3.5.4 --- XPS Study of Gallium Doped ZnO-ST --- p.58 / Chapter 2.3.6 --- FR-IR Spectra --- p.60 / Chapter 2.3.7 --- Photocatalytic Activity on Degradation of Methylene Blue --- p.61 / Chapter 2.3.8 --- Proposed Formation Mechanism for ZnO-ST --- p.64 / Chapter 2.3.9 --- Proposed Formation Mechanism for ZnO-HT --- p.68 / Chapter 2.3.10 --- Optical Property of ZnO Microspheres --- p.69 / Chapter 2.4 --- Conclusion --- p.73 / Chapter 2.5 --- References --- p.74 / Chapter Chapter 3: --- Synthesis of Hierarchical Porous Lithium Niobate Submicrometer Rods / Chapter 3.1 --- Introduction --- p.79 / Chapter 3.2 --- Experimental Section --- p.81 / Chapter 3.2.1 --- Characterization --- p.82 / Chapter 3.3 --- Results and Discussion --- p.83 / Chapter 3.3.1 --- X-Ray Diffraction Analysis --- p.83 / Chapter 3.3.2 --- SEM Study --- p.86 / Chapter 3.3.2.1 --- Surfactants Dependent Morphologies Change --- p.86 / Chapter 3.3.2.2 --- Concentrations of CTAB --- p.87 / Chapter 3.3.2.3 --- Time Dependent Morphologies Change --- p.88 / Chapter 3.3.3 --- TEM Study --- p.91 / Chapter 3.3.5 --- XPS Analysis --- p.93 / Chapter 3.3.6 --- BET Analysis --- p.96 / Chapter 3.3.7 --- Proposed Formation Mechanism --- p.97 / Chapter 3.3.7.1 --- Effect of Microemulsion --- p.97 / Chapter 3.3.7.2 --- Effect of CTAB --- p.98 / Chapter 3.3.7.3 --- Ostwald Ripening --- p.99 / Chapter 3.3.7.4 --- Formation of LiNi3O8 --- p.101 / Chapter 3.4 --- Conclusion --- p.102 / Chapter 3.5 --- References --- p.103 / Chapter Chapter 4: --- Flower-Like α-Nickel Hydroxide synthesized by hydrothermal method / Chapter 4.1 --- Introduction --- p.106 / Chapter 4.2 --- Experimental Section --- p.108 / Chapter 4.2.1 --- Synthesis of Nickel Hydroxide by Hydrothermal Method --- p.108 / Chapter 4.2.2 --- Characterization --- p.109 / Chapter 4.3 --- Results and Discussion --- p.111 / Chapter 4.3.1 --- X-Ray Diffraction Analysis --- p.111 / Chapter 4.3.2 --- SEM Study --- p.115 / Chapter 4.3.3 --- TEM and HRTEM Study --- p.116 / Chapter 4.3.4 --- XPS Analysis --- p.117 / Chapter 4.3.5 --- FT-IR Analysis --- p.119 / Chapter 4.3.6 --- BET analysis --- p.120 / Chapter 4.3.7 --- Proposed Formation Mechanism of the Flower like α-Ni(OH)2 --- p.122 / Chapter 4.4 --- Conclusion --- p.123 / Chapter 4.5 --- References --- p.124 / Chapter Chapter 5: --- Conclusions and Future Work / Chapter 5.1 --- Conclusions --- p.127 / Chapter 5.2 --- Future work --- p.129
250

Níveis de fósforo no desenvolvimento e produção de óleo essencial de Mentha piperita L. cultivada em solução nutritiva

David, Evelize de Fátima Saraiva [UNESP] 30 January 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-01-30Bitstream added on 2014-06-13T18:30:15Z : No. of bitstreams: 1 david_efs_me_botfca.pdf: 544358 bytes, checksum: 5bff6514383e868656bc07323c8417f1 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Para o estudo do desenvolvimento da Mentha piperita L. e da produção de seu óleo essencial, foram cultivadas plantas em solução nutritiva com diferentes níveis de fósforo, que constituíram diferentes tratamentos, aos quais as plantas foram submetidas. Para tanto, as plantas foram cultivadas em solução nutritiva no 2 Hoagland & Arnon (1950), na mesma solução com decréscimo de 50% e com acréscimo de 50% de fósforo. As variáveis número de folhas, comprimento de parte aérea, massa seca dos diferentes órgãos, área foliar, razão de área foliar, área foliar específica, taxa assimilatória liquida, taxa de crescimento relativo, razão de massa foliar, distribuição de massa seca, rendimento e composição de óleo essencial foram avaliadas. O delineamento experimental foi inteiramente casualizado, com três níveis de fósforo, cinco colheitas e quatro repetições, em esquema fatorial 3x5. Para a análise do óleo essencial o delineamento foi inteiramente casualizado em esquema fatorial 3x3. Os resultados foram submetidos à análise de variância e as médias foram comparadas pelo teste Tukey, com 5% de significância. O fator colheita foi avaliado por análise de regressão, exceto na avaliação da produção e composição do óleo essencial. As plantas submetidas ao maior nível de fósforo e igual a 91,5/183,0 mg L-1 apresentaram tendência de aumento do número de lâminas foliares, área foliar, massa seca de lâminas foliares, massa seca total e dos teores de mentona. As plantas submetidas ao nível intermediário de fósforo, igual a 57,5/115,0 mg L-1 apresentaram maior massa seca de caule mais pecíolos e maior teor de mentofurano. Quando as plantas foram submetidas ao menor nível de fósforo, igual a 28,7/57,5 mg L-1, foi maior a massa seca de raízes, massa seca de estolões, produção de óleo essencial e teores de mentol, acetato de mentila e pulegona... / To study the development of Mentha piperita L. and the production of essential oil plants were cultivated in nutritive solution under several levels of P. Original Hoagland & Arnon (1950) no 2 nutritive solution were one of the treatments, and the other experimental levels were this nutritive solution with 50% of the original P concentration, and added with 50% P over the original concentration. The variables evaluated were number of leaves, steam length, dry mass several organs, leaf area, leaf area ratio, specific leaf area, net assimilatory rate, relative growth rate, leaf mass ratio, dry mass distribution. Essential oil yield and composition were also assessed. A randomized factorial design 3x5 were used, with there levels of phosphorus. for essential oil, a randomized 3x3 factorial design were used. Data analysis consisted in application of ANOVA followed by the Tukey test, using the level of significance of 5%. The crop factor was studied using regression analysis, except for essential oil yield and composition. Highest P levels, 91,5/183,0 mg L-1 resulted on significantly higher values for number of leaves, leaf area, leaf dry mass, total dry mass and content menthone. Plants cultivated under intermediate P levels, 57,5/115,0 mg L-1 had higher values for stem plus petiole dry mass, and content menthofuram. When submitted to the lower level of P, 28,7/57,5 mg L-1, root dry mass, steam dry mass, menthol, essential oil yield, menthyl acetate and pulegone content were highest. Physiological indexes as leaf area ratio, leaf mass ratio, dry mass distribution of plants cultivated under the intermediate P levels were higher than those found in the P level of 91,5/183 mg L-1. We concluded that the best period to crop this plant, aiming for a highest yield of essential oil, was 60 days after transplantation... (Complete abstract click electronic access below)

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