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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.
21

Fabrication of organic-inorganic nanocomposites by colloidal processing

Luo, Dan January 2016 (has links)
Colloidal processing has been widely used for many industrial application. Electrophoretic deposition (EPD) is an important colloidal technique, which plays an important role in the fabrication of organic-inorganic composites. In this work, advanced dispersing agents with excellent adsorption, dispersion and film forming properties have been developed. The adsorption mechanism and the deposition kinetics of EPD have been studied. It is shown that catechol and salicylic groups of dispersants can form chelation bonding with metal atoms on inorganic particle surface and provide particle charging, dispersion and deposition. The aromatic dispersants can adsorb on carbon nanotubes due to π-π interactions. The long chain ionic polymeric dispersants were investigated, which provide efficient electrosteric stabilization. The film forming properties of dispersants allow dispersants with dispersed materials to deposit and form composite films on the substrate. Universal dispersing agents have been developed for the colloidal processing. These dispersants show possibilities to adsorb and disperse various organic and inorganic materials and pave the way for the fabrication of multi-functional materials for various applications. The composite materials, prepared using new dispersants showed promising corrosion protection of metals, flame retardant and energy storage properties. / Thesis / Master of Applied Science (MASc)
22

Structural and Photochemical Properties of Fe(III) Complexes with Mixed Donor a-Hydroxy Acid Chelates

Grabo, Jennifer January 2015 (has links)
No description available.
23

Sulfur Requirements of Container-grown Pin Oak and Japanese Maple

Browder, Jake Forrest 03 December 2004 (has links)
The objectives for this research were to determine: 1) whether sulfated micronutrient addition increased growth of container-grown pin oak (Quercus palustris MuÌ nchh) and Japanese maple (Acer palmatum Thunb.) seedlings by supplying micronutrients, sulfur, or decreasing substrate pH, 2) S requirements of Q. palustris and A. palmatum container-grown in a pine bark (PB) substrate, and 3) if there are any conditions that will affect these S requirements. Container grown Q. palustris and A. palmatum seedlings were grown in PB, amended (or not) with the following treatments: control (no amendment), Micromax (commercial micronutrient fertilizer [sulfate form]), K2SO4, H2SO4, HCl, chelated micronutrients, elemental S, or CaSO4. Dry weights of plants in all treatments supplying S were higher than for plants receiving no S. These data indicate that S, not micronutrient application, was the primary cause of increased growth from the addition of sulfated micronutrients. In other experiments these two species were fertilized with 8 different concentrations of S application (0, 1, 2, 5, 10, 20, 40, or 80 mg·liter-1). Regression analysis revealed dry weights of both species were near maximum at the extrapolated application concentration of 30 mg·liter-1 S, which corresponded to approximately 15 and 7 mg·liter-1 S in substrate solution for oak and maple, respectively. In another set of experiments plants were fertilized with Micromax or FeSO4 with or without lime. In the plus lime treatments (substrate pH 6.1), plant dry weights were higher in Micromax fertilized plants than for FeSO4 fertilized plants. However, in the minus lime treatment (substrate pH 4.5), FeSO4 addition effectively supplied S to plants. / Master of Science
24

Fixação de complexo de ferro II em matriz de poli(acrilato de sódio) / Fixing iron complex II in matrix of poly (sodium acrylate)

Valmir Silva de Miranda 27 July 2010 (has links)
Neste trabalho estudou-se a complexação do poli(acrilato de sódio), PAS, com aminpentacianoferrato de sódio,APCF. As reações de complexação ocorreram imediatamente com a formação de uma coloração amarela com total solubilização do polímero na solução 0,032 M molar do complexo. As soluções mostraram-se estáveis por 48 h e após esse período observou-se alterações na natureza do complexo polimérico com a formação de precipitado. O UV foi usado como ferramenta de caracterização do complexo. O máximo de absorção obtido após dissolução imediata foi de 405 nm com desvio para o azul (398 nm) e um pequeno efeito hipercrômico. As amostras mantidas à temperatura ambiente por mais de 48 h deram origem a precipitados, que como a solução, absorveram com máximo de 364, 389 e 398 nm. O Complexo PAS-APCF foi também caracterizado através de FTIR por ATR e apresentou pequenas variações no espectro do material de partida (PAS). Um incremento na intensidade da deformação axial assimétrica do grupo carboxilato (1651 cm-1) e a presença do estiramento em 2055 cm-1 do grupo cianeto, diferentemente do APCF (2048 cm-1), confirmaram a formação do complexo PAS-APCF. As freqüências de absorção observadas para o complexo foram compatíveis com a presença de estruturas mono e bidentadas de complexação. As análises de TGA e DSC também foram utilizadas para a caracterização das estruturas. O estudo modelo envolvendo a complexação de sais sódicos de diácidos orgânicos de diferentes tamanhos de cadeia (oxalato, malonato, succinato, glutarato e adipato), diferentemente do PAS, promoveu um desvio para o vermelho na frequência máxima de absorção junto de um pequeno efeito hipercrômico (421 nm). Esta variação pode também ser observada quando do emprego de acetato de sódio, indicando, provavelmente, apenas a formação de estruturas monodentadas / In this work we studied the complexation of poly (sodium acrylate), PAS, with sodium amminepentacyanoferrate, APCF. The complexation reactions occurred immediately with the formation of a yellow color with complete solubility of the polymer solution in 0.032 M molar complex. The solutions were stable for 48 h and after this period saw changes in the nature of the polymeric complex with the formation of precipitate. The spectrophotometry was used as a tool for characterization of the complex. The maximum absorption was obtained immediately after dissolution of 405 nm with a shift to the blue (398 nm) and a small hyperchromic effect. The samples kept at room temperature for more than 48 h resulted in precipitates that as the solution, absorbed with a maximum of 364, 389 and 398 nm. Complex PAS-APCF was also characterized by using FTIR and ATR spectra showed small variations in the starting material (PAS). An increase in the intensity of the asymmetric axial deformation of the carboxylate group (1651 cm-1) and the stretch at 2055 cm-1 group cyanide, unlike APCF (2048 cm-1), confirmed the formation of the PAS-APCF. The absorption frequencies observed for the complex were consistent with the presence of mono and bidentate complexation. The TGA and DSC were also used to characterize the structures. The study model involving the complexation of sodium salts of organic diacids of different chain sizes (oxalate, malonate, succinate, glutarate and adipate), unlike PAS, held a red shift in the frequency of maximum absorption with a small effect hyperchromic (421 nm). This variation may also be observed when employing sodium acetate, indicating probably the formation of only monodentate structures
25

Coordination Chemistry of Multidentate Pyrrolylaldiminate Ligands

Lee, Pei-ying 21 July 2004 (has links)
none
26

Syntheses and Complexation of {(o-PPh2C6H4)CH=NCH2CH2}3N with Chromium Group Metal Carbonyls

Hsiao, Shu-Ching 04 August 2004 (has links)
none
27

Complexation of {(o-PPh2C6H4)CH=NCH2CH2}3N with transition metal compounds

Weng, Tzu-Chieh 23 August 2005 (has links)
none
28

Modulare Synthese von neuartigen Liganden und Metallkomplexen für die Katalyse

Geis, Oliver. Unknown Date (has links)
Techn. Universiẗat, Diss., 2000--Berlin.
29

Adubação foliar de zinco quelatizado e seus efeitos na produção de capim-mombaça

Teixeira, Natália Martins January 2016 (has links)
Orientador: Reges Heinrichs / Resumo: Com a intensificação da produção pecuária são necessários avanços no manejo e adubação das plantas forrageiras, para aumentar a produtividade e manter-se competitivo no setor. A utilização de tecnologias, como a adubação foliar com micronutrientes, torna-se uma importante ferramenta para atingir a plenitude na produção agropecuária. O experimento foi conduzido em casa de vegetação da UNESP, Campus de Dracena, em vasos com capacidade para 4 dm3 de terra, com o objetivo de avaliar a produção de massa seca, teor e quantidade de nutrientes e qualidade bromatológica da forrageira Megathyrsus maximum (syn. Panicum maximum) cv. Mombaça adubado com zinco quelatizado, via foliar, em dois solos com distinta disponibilidade de Zn. O delineamento experimental foi inteiramente casualizado com quatro repetições. Os tratamentos foram arranjados em esquema fatorial 6X2, sendo seis doses foliares de zinco quelatizado, e duas condições de solo (com baixo e médio teor de Zn), acrescidos de um tratamento com sulfato de zinco e dois tratamentos com coquetel de nutrientes. Foram utilizados o Neossolo Quartzarênico, distrófico, fase cerrado, com baixo teor de zinco e o Argissolo Vermelho Amarelo, distrófico, com teores médios de zinco. Nas condições em que foi realizada a pesquisa, os resultados permitem concluir que: a aplicação foliar de Zn quelatizado, coquetel de nutrientes e sulfato de zinco não influenciaram a produção de massa seca do capim-mombaça; o teor de Zn na massa seca do capim-mombaç... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With the intensification of livestock production are needed advances in the management and fertilization of forage crops, to enhance productivity, reducing costs and remaining competitive in the industry. The use of technologies such as foliar fertilizer with micronutrients, it becomes an important tool to achieve fulfillment in agricultural production. The experiment was conducted at UNESP greenhouse, Campus de Dracena, situated 421 meters above sea level, 21 ° 27 'south latitude and 51 ° 36' west longitude, in pots with a capacity of 4 dm3 of land, in order to evaluate the dry matter production, content and amount of nutrients and chemical quality of the forage Megathyrsus maximum (syn. Panicum maximum) cv. Mombasa fertilized with chelated zinc, foliar, in two soils with different availability of Zn. The experimental design was completely randomized with four replications. The treatments were arranged in a factorial scheme 6X2, six leaf doses of zinc chelate, and two soil conditions (low and medium Zn content), plus a treatment with zinc sulfate and two treatments with cocktail nutrients. The Entisol were used, dystrophic, cerrado phase, with low zinc content and Ultisol, dystrophic, with average zinc content. The conditions under which the survey was conducted, the results showed that: foliar application of chelated Zn cocktail of nutrients and zinc sulfate did not affect the dry matter production of mombaça grass; Zn content in the dry mass of mombaça grass was directly p... (Complete abstract click electronic access below) / Mestre
30

Fixação de complexo de ferro II em matriz de poli(acrilato de sódio) / Fixing iron complex II in matrix of poly (sodium acrylate)

Valmir Silva de Miranda 27 July 2010 (has links)
Neste trabalho estudou-se a complexação do poli(acrilato de sódio), PAS, com aminpentacianoferrato de sódio,APCF. As reações de complexação ocorreram imediatamente com a formação de uma coloração amarela com total solubilização do polímero na solução 0,032 M molar do complexo. As soluções mostraram-se estáveis por 48 h e após esse período observou-se alterações na natureza do complexo polimérico com a formação de precipitado. O UV foi usado como ferramenta de caracterização do complexo. O máximo de absorção obtido após dissolução imediata foi de 405 nm com desvio para o azul (398 nm) e um pequeno efeito hipercrômico. As amostras mantidas à temperatura ambiente por mais de 48 h deram origem a precipitados, que como a solução, absorveram com máximo de 364, 389 e 398 nm. O Complexo PAS-APCF foi também caracterizado através de FTIR por ATR e apresentou pequenas variações no espectro do material de partida (PAS). Um incremento na intensidade da deformação axial assimétrica do grupo carboxilato (1651 cm-1) e a presença do estiramento em 2055 cm-1 do grupo cianeto, diferentemente do APCF (2048 cm-1), confirmaram a formação do complexo PAS-APCF. As freqüências de absorção observadas para o complexo foram compatíveis com a presença de estruturas mono e bidentadas de complexação. As análises de TGA e DSC também foram utilizadas para a caracterização das estruturas. O estudo modelo envolvendo a complexação de sais sódicos de diácidos orgânicos de diferentes tamanhos de cadeia (oxalato, malonato, succinato, glutarato e adipato), diferentemente do PAS, promoveu um desvio para o vermelho na frequência máxima de absorção junto de um pequeno efeito hipercrômico (421 nm). Esta variação pode também ser observada quando do emprego de acetato de sódio, indicando, provavelmente, apenas a formação de estruturas monodentadas / In this work we studied the complexation of poly (sodium acrylate), PAS, with sodium amminepentacyanoferrate, APCF. The complexation reactions occurred immediately with the formation of a yellow color with complete solubility of the polymer solution in 0.032 M molar complex. The solutions were stable for 48 h and after this period saw changes in the nature of the polymeric complex with the formation of precipitate. The spectrophotometry was used as a tool for characterization of the complex. The maximum absorption was obtained immediately after dissolution of 405 nm with a shift to the blue (398 nm) and a small hyperchromic effect. The samples kept at room temperature for more than 48 h resulted in precipitates that as the solution, absorbed with a maximum of 364, 389 and 398 nm. Complex PAS-APCF was also characterized by using FTIR and ATR spectra showed small variations in the starting material (PAS). An increase in the intensity of the asymmetric axial deformation of the carboxylate group (1651 cm-1) and the stretch at 2055 cm-1 group cyanide, unlike APCF (2048 cm-1), confirmed the formation of the PAS-APCF. The absorption frequencies observed for the complex were consistent with the presence of mono and bidentate complexation. The TGA and DSC were also used to characterize the structures. The study model involving the complexation of sodium salts of organic diacids of different chain sizes (oxalate, malonate, succinate, glutarate and adipate), unlike PAS, held a red shift in the frequency of maximum absorption with a small effect hyperchromic (421 nm). This variation may also be observed when employing sodium acetate, indicating probably the formation of only monodentate structures

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