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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.
191

Automatizace pěstebního procesu z hlediska hodnoty pH a obsahu živin v substrátu / Automation of the cultivation process in term of pH factor and nutrient content in substrate

Černý, David January 2016 (has links)
The main goal of thesis is creation of the automatic growroom and realisation of the controller. The controller will be able for measurement temperature, pH and pH of soil. The soil pH is a measure of the acidity or alkalinity in soils. The other part is about measurement of pH and conductivity. The practical part begun with measurement of pH by laboratory pH meter. These measured figures I compared with figures measured with my pH meter created by my own. The other part describe realisation of my own pH meter and control software. The pH meter was fully managed and also was created describtion for the growroom.
192

Sledování jakosti hovězího masa během zrání

Kavanová, Monika January 2016 (has links)
The diploma thesis is dealing with the monitoring of quality of beef meat during the process of ageing. In the literary overview the terms beef meat and quality are defined, the consumption of beef meat is stated and the composition and attributes of the beef meat are described. The list of factors that influence the quality of beef meat follows. The factors are divided into intravital and postmortal. The postmortal processes are described more thoroughly; the possibilities and consequences of their abnormal progress and other quality defects are added. The practical part of the thesis is devoted to the comparison of chosen parameters of heifer meat (n = 6) of the Aberdeen Angus breed (AA) and Czech Fleckvieh breed (CS). In the cut-out parts Musculus longissimus dorsi (NR) and Musculus adductores (SŠ) the parameters of pH, electrical conductivity and color were observed for eight weeks of aging in the vacuum (1-2 °C). The color was measured spectrofometrically with the application of the CIELAB color space.
193

Fertirrigação nitrogenada por gotejamento em cafezal e sua influência em características químicas do solo / The nitrogen drip fertirrigation in coffee plantation and its influence on the chemical characteristics of the soil

Costa, Édio Luiz da 29 June 2005 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-03-17T18:52:35Z No. of bitstreams: 1 texto completo.pdf: 1060929 bytes, checksum: 30f6482455b84dda2fe1bf10374f310e (MD5) / Made available in DSpace on 2017-03-17T18:52:35Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1060929 bytes, checksum: 30f6482455b84dda2fe1bf10374f310e (MD5) Previous issue date: 2005-06-29 / Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Com o aumento das fronteiras cafeeiras e a necessidade de uma agricultura mais eficiente, surge a necessidade de informações técnicas que melhorem a rentabilidade, a qualidade final do produto e a conservação do ambiente. A irrigação é uma técnica que vem em auxílio dos fatores mencionados acima. No entanto, o aumento da demanda por recursos hídricos tem despertado nos usuários a necessidade do uso racional da água, o que se tem buscado com o uso de métodos de irrigação mais eficientes, como a irrigação localizada. Aliado à maior eficiência na aplicação de água, a eficiência na utilização de fertilizantes tem sido buscada com o uso da fertirrigação, que se ajusta perfeitamente aos métodos de irrigação localizada, especialmente no sistema de gotejamento. A fertirrigação no sistema de gotejamento pode trazer alterações químicas no solo ainda pouco elucidadas pela pesquisa. O objetivo com este trabalho foi proporcionar informações quanto às alterações advindas do uso de diferentes fontes e doses de Nitrogênio aplicadas por fertirrigação e adubação convencional nas características do solo e do cafeeiro irrigado por gotejamento. Os trabalhos foram conduzidos na Fazenda Laje, localizada em Teixeiras- MG, entre agosto de 2003 e julho de 2004. A variedade estudada foi Catuaí Vermelho, plantada no espaçamento de 2,5 x 0,8 m (5.000 plantas ha -1 ), irrigadas por gotejamento. As características do solo avaliadas foram: CE, pH, Al 3+ , N-NO 3- , N-NH 4+ e V. As características analisadas da planta foram: altura da planta, diâmetro do caule, percentagem de frutos retidos na planta, número de entrenós emitidos, produtividade e análise de nutrientes na folha. Foram conduzidos dois ensaios. No ensaio 1, na análise dos dados das características do solo, adotou-se o esquema de parcelas subdivididas em que as fontes de N (uréia, sulfato de amônio e nitrato de cálcio) e as doses de N (200, 400 e 600 kg ha -1 ano -1 ) constituíram os tratamentos da parcela, e as camadas (0-0,10; 0,10-0,20; 0,20-0,30 e 0,30-0,50 m) e as posições amostradas (dentro e fora do bulbo úmido), com restrições à casualização, constituíram os tratamentos das subparcelas. Na análise das características do cafeeiro adotou-se o fatorial 3x3, sendo três fontes e três doses de N, citadas anteriormente. No ensaio 2, na análise dos dados das características do solo, adotou-se o esquema de parcelas subdivididas em que as fontes de N (uréia, sulfato de amônio e nitrato de cálcio) e os modos de aplicação de N (fertirrigação e adubação convencional) constituíram os tratamentos da parcela, e as camadas (0-0,10; 0,10-0,20; 0,20-0,30 e 0,30-0,50 m) e as posições amostradas (dentro e fora do bulbo úmido), com restrições à casualização, constituíram os tratamentos das subparcelas. Na análise das características do cafeeiro adotou-se o fatorial 3x2, sendo três fontes de N e dois modos de aplicação de N, citadas anteriormente. As doses de nitrogênio alteraram os valores de saturação de bases, condutividade elétrica, pH e as formas de nitrogênio na região do bulbo úmido. A fonte sulfato de amônio foi responsável pelo maior teor de N-mineral no solo, reduzindo o risco de perdas por lixiviação. A nitrificação foi maior com a aplicação do sulfato de amônio na fertirrigação. Na fertirrigação com a uréia, o teor de N-NH 4+ aumentou com a profundidade do solo. A uréia não proporcionou acidificação do solo. As características da planta do cafeeiro não foram alteradas com as fontes, doses e o modo de aplicação do nitrogênio. As fontes de nitrogênio alteraram as características nutricionais do cafeeiro. A produtividade do cafeeiro foi maior com a fertirrigação. / With the increased coffee boundaries and the need for a more efficient agriculture, there appears the requirement for technical information that would improve the profitability, the final quality of the product, and the environmental preservation. The irrigation is an useful technique for the improvement of these factors. However, the increased demand for water resources has stimulating the users’ need for the rational water use, which has been searched by the application of more efficient irrigation methods such as the located irrigation. Together with the highest efficiency in water application, the efficiency in the use of fertilizers has been searched by using the fertirrigation, that is perfectly adjusted to the located irrigation methods, especially in the drip irrigation system. When fertirrigation is used in association with the drip system, some poorly elucidated chemical alterations might occur in the soil. This study was conducted to provide information about the changes proceeding from the use of different nitrogen sources and doses applied by fertirrigation and conventional fertilization upon the characteristics of the soil and the drip-irrigated coffee shrub. The work was carried out with the Catuaí Vermelho cv., during the period from August 2003 to July 2004, in Laje farm located in Teixeiras county-MG. This variety was planted at spacings of 2.5 x 0,8 m (5,000 plants ha - ) and the drip irrigation was used. The following characteristics of the soil were evaluated: CE, pH, Al 3+ , N-NO 3 - , N-NH 4+ , and V. The following characteristics of the plant were analyzed: the plant height, stem diameter, percentage of coffee beans kept in the shrub, number of the emitted internodes, and productivity and analysis of the leaf nutrients. Two assays were accomplished. In assay 1, when analyzing the data of the soil characteristics, the split-plot design was used where the N sources (urea, ammonium sulfate and calcium nitrate) and N doses (200, 400 and 600 kg ha -1 year -1 ) constituted the treatments of the plot, whereas the layers (0-0.10; 0.10-0.20; 0.20-0.30; and 0.30-0.50 m) and the sampled positions (inside and outside the wet bulb), with restrictions to randomization, constituted the treatments of the subplots. In analyzing the characteristics of the coffee shrub, the factorial 3x3 was adopted, with three sources and three doses of N, previously mentioned. In assay 2, when analyzing the data of the soil characteristics, the split-plot design was used, where the N sources (urea, ammonium sulfate and calcium nitrate) and the N application methods (fertirrigation and conventional fertilization) constituted the treatments of the plot, whereas the layers (0-0.10; 0.10-0.20; 0.20-0.30 and 0.30-0.50 m) and the sampled positions (inside and outside of the wet bulb), with restrictions to randomization, constituted the treatments of the subplots. In analyzing the characteristics of the coffee shrub, the factorial 3 x 2 was adopted, as being three N sources and two N- application methods, previously mentioned. The N doses changed the values of the base saturation, electric conductivity, pH, and the nitrogen forms in the wet bulb region. The source of the ammonium sulfate was responsible for the highest content of N-mineral in the soil, thus reducing the risk of leaching losses. The nitrification was higher when the ammonium sulfate was applied by fertirrigation. When urea was applied by fertirrigation, the content of N-NH 4+ was increased with soil depth. The urea provided no acidification to the soil. The characteristics of the coffee shrub were not changed with the sources, doses and the application method of nitrogen. The N sources changed the nutritional characteristics of the coffee shrub. The productivity of the coffee shrub was higher with fertirrigation. / Tese importada do Alexandria
194

Atributos químicos e crescimento de plantas em solos com aplicação de resíduos urbanos / Chemical attributes and plant growth in soils with urban wastes application

Garcia, Gabriel Furtado January 2016 (has links)
O uso de composto de lixo (CL) e de lodo de esgoto (LE) na agricultura é uma alternativa viável para a melhor disposição destes resíduos urbanos em solos. Estudos de longo prazo podem melhorar o entendimento da dinâmica e as modificações que estes materiais ocasionam no solo e na resposta de plantas. O objetivo desse estudo foi avaliar os efeitos residuais (aplicações entre 2002 e 2006) e imediatos (reaplicação em 2015, após pousio) dos resíduos CL e LE, em dois solos [Latossolo Vermelho distroférrico (LVd) e um Argissolo Vermelho distrófico (PVd)], quanto às modificações em atributos químicos do solo, elementos-traços (ET) e resposta de plantas de aveia (Avena sativa) e milho (Zea mays). O experimento consta de colunas de solo, com aplicação de duas doses dos resíduos, CL e LE, com base no suprimento de nitrogênio, sendo a maior repetida e enriquecida com ET (Cd, Cu, Ni, Pb e Zn), além de tratamentos com adubação mineral e testemunha. Quanto aos efeitos residuais, na camada de 0-20 cm de ambos os solos, os resíduos promoveram maiores teores de C orgânico e P disponível e valores de CTC, porém o CL resultou em maiores valores de pH do solo. Com exceção do Cu, os teores de ET no solo diminuíram com o tempo. A produção de matéria seca de aveia diminuiu expressivamente após o longo período de pousio, possivelmente pela limitação em N. Os tratamentos com LE enriquecido com ET resultaram em maior acúmulo destes elementos na parte aérea da aveia. Após a reaplicação dos resíduos, o LE resultou em maior produção de matéria seca e maior acúmulo de macronutrientes (N, P, Ca e Mg) pelas plantas de milho em comparação ao CL. Os tratamentos com CL e LE enriquecidos determinaram nas plantas teores de ETS não essenciais considerados fitotóxicos. / The use of urban solid waste compost (SWC) and sewage sludge (SS) in agriculture is a viable alternative for better disposal of these urban residues in soils. Long-term studies may improve the understanding of the dynamic and changes caused by these materials in soils and plant responses. The aim of this study was to evaluate residual effects (applications from 2002 to 2006) and immediate effects (application in 2015, after a fallow time) of SWC and SS residues in two soils [Typic Haplorthox (LVd) and Arenic Paleudult (PVd)], regarding soil chemical attributes and trace elements (ET) and oat (Avena sativa) and corn (Zea mays) plant responses. The experiment is carried out in soil columns with application of two doses of both SWC and SS and also with the major dose enriched with ET (Cd, Cu, Ni, Pb and Zn), besides mineral fertilization and control treatments. Residue doses were established according N supply. Regarding residual effects in the 0-20 cm layer of both soils SWC and SS materials improved organic C and available P contents and CEC values, but soil pH was higher for SWC treatments. Except for Cu, soil ET contents decreases with time. Oat dry matter production was very small after the fallow time possibly due to low residual N supply. Treatments enriched with ET resulted in higher contents of these elements in oat shoots. After residue reapplication SS caused higher corn dry matter production and macronutrient (N, P, Ca and Mg) contents than SWC. Non-essential metal in levels possibly toxic for corn plants resulted from treatments with SWC and SS enriched with ET.
195

Mechanisms of pH change in wood ant (\kur{Formica polyctena}) nests / Mechanisms of pH change in wood ant (\kur{Formica polyctena}) nests

JÍLKOVÁ, Veronika January 2011 (has links)
The aim of this study was to reveal mechanisms of pH change in wood ant nests. Contents of basic cations and glucose brought in ant food, i.e., honeydew and prey, into the nests were measured. Manipulation experiment was carried out to test effects of glucose and Ca2+ cations brought by ants into the nest on increase in pH.
196

Diversidade e potencial enzimático de fungos filamentosos isolados do solo, Semi-Árido, Pernambuco, Brasil

OLIVEIRA, Luciana Gonçalves de 03 July 2009 (has links)
Submitted by Leonardo Freitas (leonardo.hfreitas@ufpe.br) on 2015-04-08T19:57:48Z No. of bitstreams: 2 Tese Luciana de Oliveira.pdf: 1908204 bytes, checksum: d106719829e859b269968dc234a2c86c (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-04-08T19:57:48Z (GMT). No. of bitstreams: 2 Tese Luciana de Oliveira.pdf: 1908204 bytes, checksum: d106719829e859b269968dc234a2c86c (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2009-07-03 / CAPES; PPBio; CNPq; DAAD / Os fungos compreendem um grupo heterogêneo de microrganismos, atuando como sapróbios, parasitas e simbiontes. Como sapróbios, podem viver em diversos ambientes, especialmente no solo. Este trabalho teve como objetivos o isolamento, identificação e atividade enzimática (lacase e peroxidase) de fungos filamentosos do solo do Vale do Catimbau, semi-árido pernambucano. Quatro coletas de solo foram feitas durante os períodos chuvosos (2) e de estiagem (2). Foram identificadas 87 espécies de fungos filamentosos pertencentes aos fungos anamorfos (74), Zygomycota (8) e Ascomycota (6). Penicillium e Aspergillus predominaram com 28 e 18 espécies, respectivamente. Aspergillus fumigatus, A. versicolor, A. terreus, Fusarium solani, Penicillium commune, P. decumbens, P. restrictum, P. verruculosum e P. waksmanii foram classificados como abundantes. Não foram observadas diferenças significativas entre as unidades formadores de colônia em relação aos períodos chuvoso e de estiagem e às superfície e profundidade do solo. O Índice de Diversidade de Shannon-Wiener foi de 4,84 bits por indivíduo. Das espécies identificadas, Pestalotiopsis palustris e Pestalozziella artocarpi estão sendo citadas pela primeira vez para as Américas do Sul e Latina, respectivamente. Trinta e duas espécies foram testadas quanto à atividade enzimática, onde 22 e 27 foram positivas para a lacase e peroxidase, respectivamente. Chaetomium globosum apresentou melhor atividade lacase, enquanto Pithomyces chartarum revelou melhor atividade para peroxidase. O pH ótimo para atividade lacase foi 3,0 em Pithomyces chartarum e, 4,5 em C. pallescens para peroxidase. A temperatura ótima foi observada em C. globosum foi 70ºC por 60 min para lacase e, 50ºC por 60 min em Mirothecium roridum para peroxidase. Curvularia pallescens, Pestalotiopsis palustris, Pestalozziella artocarpi e Scopulariopsis chartarum estão sendo citadas como primeiro registro com atividade para fenoloxidases. Os resultados desta pesquisa indicam que os fungos anamórficos predominam no solo do Vale do Catimbau e que as espécies testadas quanto a produção de fenoloxidases são promissoras para a biotecnologia.
197

O efeito do hidróxido de cálcio, do carbonato e do bicarbonato de sódio na qualidade de água e no desempenho zootécnico do camarão Litopenaeus vannamei cultivado com tecnologia de bioflocos (BFT)

Furtado, Plínio Schmidt January 2011 (has links)
Dissertação(mestrado)-Universidade Federal do Rio Grande, Programa de Pós–Graduação em Aqüicultura, Instituto de Oceanografia, 2011. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2012-08-17T12:47:58Z No. of bitstreams: 1 dissertao plinio em pdf.pdf: 641234 bytes, checksum: d4bb74480675f59d2f0875e7836a76e1 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-08-21T17:46:11Z (GMT) No. of bitstreams: 1 dissertao plinio em pdf.pdf: 641234 bytes, checksum: d4bb74480675f59d2f0875e7836a76e1 (MD5) / Made available in DSpace on 2012-08-21T17:46:11Z (GMT). No. of bitstreams: 1 dissertao plinio em pdf.pdf: 641234 bytes, checksum: d4bb74480675f59d2f0875e7836a76e1 (MD5) Previous issue date: 2011 / O camarão Litopenaeus vannamei é o mais cultivado em sistemas super-intensivos em meio a flocos microbianos (BFT) e sem renovação de água. Nestes sistemas de bioflocos a tendência natural é que ocorra a diminuição do material carbonático ao longo do cultivo, devido aos processos de nitrificação que reduzem a alcalinidade na forma de carbonatos e bicarbonatos. Além disso, o pH pode diminuir devido a redução da alcalinidade e ao acúmulo de dióxido de carbono dissolvido, proveniente da respiração. O objetivo do estudo foi avaliar o efeito da aplicação de hidróxido de cálcio, carbonato e bicarbonato de sódio na qualidade de água do cultivo do L. vannamei em sistema BFT. Para tal, 600 juvenis (6g) foram estocados em 12 tanques com 150L de volume útil (ρ=333/m³). Os camarões foram alimentados duas vezes por dia, com ração comercial (Guabi®) seguindo tabela de alimentação por 60 dias de experimento. Foram avaliados quatro tratamentos com três repetições cada: T1- Na2CO3 (correção do pH acima de 7,5); T2- Ca(OH)2 (correção da alcalinidade acima de 100mg/L de CaCO3 e pH acima de 7,5); T3- NaHCO3 (correção da alcalinidade acima de 100 mg/L de CaCO3 ); e T4- Controle (sem correção do pH e alcalinidade). Para correção de pH, alcalinidade e ambos, foi utilizado carbonato de sódio 0,06 g/L, bicarbonato de sódio 0,20 g/L e cal hidratada 0,15 g/L, respectivamente. Os resultados dos parâmetros físicos, químicos, biológicos apresentaram diferença significativa (p<0,05) entre os tratamentos. Os animais do controle mostraram desempenho zootécnico inferior (p<0,05) aos demais tratamentos. As aplicações de carbonato de sódio (Na2CO3) e bicarbonato de sódio (NaHCO3) resultaram em condições favoráveis de qualidade de água para o crescimento dos bioflocos e dos camarões cultivados, no entanto os custos destes compostos os tornam pouco atrativos para aplicação em escala comercial. Já a cal hidratada apresentou a melhor relação custo-benefício. Por fim, este estudo torna claro que os níveis de alcalinidade e pH decrescem ao longo do cultivo e que os níveis de CO2 dissolvido se incrementam em sistemas super-intensivos, com bioflocos, sem renovação de água. Além disso, a qualidade da água de cultivo e o desempenho zootécnico dos camarões são afetados negativamente quando os níveis de alcalinidade permanecem por longos períodos abaixo de 100 mg CaCO3/L e o pH abaixo de 7. Portanto, é necessária a correção da alcalinidade e do pH através da aplicação de materiais carbonáticos ou hidróxido de cálcio. / The white shrimp Litopenaeus vannamei is the most reared in super-intensive biofloc systems (BFT) and without water renewal. In BFT systems there is a natural tendency to decrease of carbonate material (carbonates and bicarbonates) along the rearing due to nitrification that consumes alkalinity. In addition, the pH may be decreased due to reduction of alkalinity and increase of dissolved carbon dioxide. This study was to evaluated the influence of pH and alkalinity in the rearing of L. vannamei without water renewal. The experiment was carried out using 600 juveniles (6 g) stocked in 12 tanks of 150L, for a final stocking density of 333 m-³). Shrimp were fed twice daily with commercial feed (Guabi ®) following feeding table for 60 days of experiment. There were four treatments with three replicates each: T1 – Na2CO3 (pH correction above 7.5), T2 – Ca(OH)2 (pH correction above 7.5 and alkalinity above 100 mg / L CaCO3), T3- NaHCO3 (correction of the alkalinity above 100 mg / L CaCO3) and T4 - Control (without correction of pH and alkalinity). For pH correction, alkalinity and both, it was used sodium carbonate 0.06 g / L, sodium bicarbonate 0.20 g / L hydrated lime and 0.15 g / L, respectively. It were detected significant differences (p <0.05) of the physical, chemical, biological among treatments. In the Control shrimps showed lower growth performance (p <0.05) than shrimps of other treatments. The applications of sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3) improve water quality for development of bioflocs and performance shrimps. However, costs of these compounds make them unattractive for commercial scale application. Since hydrated lime (Ca(OH)2) showed the most cost-effective. Finally, this study clarify that the results obtained in the treatment control levels of alkalinity and pH decrease during the rearing, and that CO2 levels would be increased in super-intensive systems, with bioflocs without water renewal. In addition, water quality and growth performance of shrimp are adversely affected when the levels of alkalinity remain for long periods under 100 mg CaCO3/L and pH below 7. Therefore, it is necessary to correct the alkalinity and pH through the application of carbonate materials or calcium hydroxide.
198

Radionuclide behaviour in hyperalkaline systems relevant to geological disposal of radioactive waste

Smith, Kurt January 2014 (has links)
In many countries the current plan for the management of intermediate and high level radioactive wastes is to dispose of the radioactive materials underground in a Geological Disposal Facility (GDF) to prevent release of radioactivity to the environment. In the UK, the repository for intermediate level waste may be backfilled with cementitious material and it is clear that grout and cement will be used during many disposal concepts. Upon saturation, the cement will react creating a region of hyperalkaline geochemical conditions extending away from the GDF, within which, significant changes in radionuclide behaviour are expected. Therefore, this thesis utilises a range of experimental and analytical techniques to try to gain a mechanistic understanding of the behaviour of some key radionuclides (U(VI), Np(V) and Eu(III) as an analogue for Cm(III)/Am(III)) in a range of high pH systems of direct relevance to any cementitious GDF. U(VI) interaction with calcite (calcium carbonate, a common component in high pH cements and the natural environment) surfaces was studied in the 'old' (Ca(OH)2 solution; pH 10.5) and 'young' (Na+, K+, Ca2+; pH 13.3) leachates. In the 'old' leachate, luminescence spectroscopy, batch experiments and kinetic modelling suggested that at low concentrations (smaller or equal to 0.42 µM) a Ca2UO2(CO3)3-like surface complex formed. At higher concentrations, batch experiments, extended X-ray absorption fine structure spectroscopy and luminescence suggested that a surface mediated precipitation mechanism was controlling U(VI) concentrations. Further TEM analysis confirmed that a calcium uranate (CaUO4) solid phase was forming on the calcite surfaces. In the 'young' leachate, batch experiments showed that U(VI) had little affinity for the calcite surface, with no statistically relevant removal from solution observed over a 18 month period. Small angle X-ray diffraction data demonstrated that the U(VI) was probably present in the form of U(VI) intrinsic colloids. Np(V) solubility and sorption to calcite under hyperalkaline conditions were studied using batch, X-ray absorption spectroscopy, and geochemical modelling techniques. It was determined that Np(V) solubility in 'old' cement leachates was consistent with the literature. However, in 'young' cement leachates, an unidentified calcium containing phase was controlling solubility. It was demonstrated that sorption to calcite in 'old' leachates was controlled by the formation of a >CO3NpO2 surface complex, whereas, in the 'young' leachates interaction with the calcite surface was controlled by a precipitation mechanism. Eu(III) sorption to a potential GDF backfill material, Nirex Reference Vault Backfill (NRVB) cement, was studied. The kinetics of removal were rapid with 98.5% Eu(III) removal within 24 hours. Ultrafiltration experiments indicated that all Eu(III) remaining in solution was associated with NRVB derived colloids. Additional experiments using ethylenediaminetetraacetic acid (EDTA) as a competing ligand show that removal from solution was significantly reduced at high concentrations (>0.01 M). These EDTA experiments also indicated some irreversibility in the systems, possibly caused by incorporation into the C-S-H or calcite structures.
199

On the theory of combinatorial independence

Crapo, Henry H. January 1964 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mathematics, 1964 / Vita. / Includes bibliographical references (leaves 195-200). / by Henry H. Crapo. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Mathematics
200

Kombuchans mikrobiologi : Hur olika tillredningssätt påverkar kombucha. / The Microbiology of Kombucha : How different preparation methods affect kombucha.

Gallegos Wallgren, Emil, Nylind, Emil January 2021 (has links)
No description available.

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