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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.
161

Alternating current electrocoagulation (AC/EC) of fine particulate suspensions

Ifill, Roy Oswald. January 2010 (has links)
Thesis (Ph. D.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on June 18, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Engineering, Department of Chemical and Materials Engineering, University of Alberta. Includes bibliographical references.
162

Beiträge zur kenntnis der Peptischen und Tryptischen Verdauung des Eiweisses

Borkel, Curt, January 1903 (has links)
Thesis (doctoral)--Universität Leipzig, 1903. / Cover title. Includes references.
163

An exploratory study of using hydrogen peroxide as oxygen source in aerobic upflow sludge blanket reactor /

Poon, Wing Chi. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 114-120). Also available in electronic version.
164

Study on the role of sulfate reduction and autotrophic denitrification to achieve excess sludge minimization for Hong Kong sewage /

Lau, G Ngai. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 96-105). Also available in electronic version.
165

Les Alcalins, leur rôle sur les fonctions de l'estomac, leur emploi dans la thérapeutique gastrique.

Binet, Maurice. January 1905 (has links)
Th.--Méd.--Paris, 1904-1905. / Paris, 1904-1905 N ° 145.
166

Gut throughput rate and satiation of the invasive Lionfish (Pterois volitans) and its potential impact on an endemic, endangered Labrid fish Halichoeres socialis

Garner, James Graham 31 July 2017 (has links)
The invasive Indo-Pacific Lionfish Pterois volitans has been recognized as a severe threat to indigenous fish species on Caribbean reefs. Previous studies have identified an extensive variety of Caribbean fishes in the stomachs of lionfish, but few have tried to quantify the impact these invaders could have on endemic or threatened species. The threatened Labrid fish Halichoeres socialis has been identified as the primary component of lionfish diet in Belizean lagoonal reef systems. This study aims to answer two questions: what is the average maximum number of prey-fish a lionfish can consume in one sitting, and at what rate can these lionfish pass a meal of three prey fish completely? To test lionfish satiation, the subjects were fed as many Pseudohemiculter dispar (a commercially available surrogate) as they could eat within a fifteen-minute window. During the digestion rate experiment, lionfish were fed three similarly sized P. dispar and allowed to digest in 3, 6, 9, 12, 15, 19, and 24 hour blocks. From observing prey throughput under near optimal laboratory conditions, the maximum potential impact of lionfish on native populations of Caribbean reef dwelling fishes can be estimated. Given the volume and mass of prey items consumed in this study between 593 and 4658 individual H. socialis could be consumed by a single lionfish in one year. Coupled with further investigation into H. socialis stock numbers, lionfish (P. volitans) could be considered a potentially immanent threat to fishes that exhibit body morphometrics like those of H. socialis at any stage of their life-history.
167

The role of anaerobic digestion in achieving soil conservation and sustainable agriculture for sustainable development in the UK

Duruiheoma, Franklin I. January 2015 (has links)
The subjection of soils to degradation directly and indirectly from rising world food demand and resultant intensified agricultural production, population growth, and climate change, demand that soils are better protected. The role of AD in addressing this challenge is examined using a pragmatic research paradigm and the questions: How can we raise awareness of AD in the UK? What factors motivate and hinder farmers towards adopting improved technology and sustainable agricultural practises? What is the perception of farmers about soils? To what extent does sustainable agriculture incorporate soil conservation in theory and practice? What role can legislation and policies play in AD adoption in the UK? The research was in two phases; qualitative and quantitative. The qualitative phase involved interviews with 21 AD stakeholder in the UK using electronic mail. The stakeholders who were divided into groups according to their expertise, were interviewed to explore their views on the areas of focus in the UK strategy and action plan regarding raising awareness of the technology, soil conservation, sustainable agriculture and sustainable development. Thematic analysis of interview data was carried out using MAXQDA 11 statistical software. The quantitative phase involved an online survey of 283 UK farmers aided by Yellow Pages directory for UK, Natural England directory, Twitter and electronic mail. Using SPSS 22.0 statistical software, the Chi square test was used to check for relationships between the variables measured at 95% confidence level (p < .05). Relationship strength was measured by means of Cramer’s V and Phi values. Answers to the 1st research question showed that: aligning AD with sustainable development goals, community AD and localism, small AD plants, provision of an available market for AD products, building UK skills and diversifying biogas use from AD are positive options for raising awareness of AD. Response to 2nd research question revealed: significant relationships between interests in agricultural technology and gender, level of education, and farm size; between knowledge of what AD is and gender, level of education and farm size; between interest in AD and age; between willingness to invest in AD if it improved soil properties and farm ownership; and between organic farming practice and age, farm type and farm size. Responding to the third research question, farmers’ describe soils in abstract, scientific, physical attribute and functional terms; awareness of soil benefits other than crop production was significantly related to age, and farm ownership; educational level was significantly related to familiarity with soil conservation, and opinion on whether soil should be protected like other natural resources. Findings regarding the 4th and 5th research questions showed: limited understanding of soil matters as a key challenge that has restricted the priority given to soil conservation, while level of education, knowledge of soil conservation and sustainable development and understanding of sustainable agriculture were also identified as influencing factors; digestate from AD is the main benefit viewed to contribute to soil conservation; finance, policy and legislation, low awareness and understanding, lack of feedstock and market, land use conflict and inefficiency of AD plants were identified as barriers to AD in the UK; promoting AD, providing finance, minimizing bureaucracy and simplification of AD systems are options for promoting AD adoption. This thesis also documents the implications of these findings for knowledge, policy and practice, and based on these recommendations are made, some of which are: better engagement of farmers in policy development for AD and soil management; use of small AD plants, demonstration, networking and training for AD adoption; promote soil conservation in theory and practice; and provision of enhanced support for owners, potential investors and farmers through incentives, simplified planning approval process, and available market for AD product.
168

Estudo da acidogênese e metanogênese aplicada no tratamento da vinhaça da cana-de-açúcar

Peruzzo, Vanessa Verona 22 June 2017 (has links)
A vinhaça, água residuária do processo, apresenta em sua composição DQO de 20 a 100 g DQO.L-1 e um ótimo potencial de produção de biogás por meio da digestão anaeróbia. Para avaliar a capacidade de produção de biogás, foram realizados experimentos sob o efeito gradual da carga orgânica volumétrica (COV) e da relação A/M, avaliando a etapa metanogênica. Como no processo de fabricação do etanol é adicionado ácido sulfúrico para evitar a contaminação bacteriana, foi avaliado a interferência da adição de diferentes concentrações de sulfetos no processo em valore de pH 7,0 e 7,5. O fermentador foi alimentado com Na2S.9H2O, variando a concentração do íon S2- de 0 a 1000 mg.L-1. Para obter uma boa eficiência na produção de metano, a etapa acidogênica também foi avaliada. Para isso, se manteve as mesmas concentrações de biomassa e substrato, porém, ajustando os valores de pH em 5,0, 5,5, 6,0 e 6,5. Na etapa metanogênica uma satisfatória redução da elevada carga orgânica presente na vinhaça foi alcançada, com eficiência de remoção entre 82,0% e 90,3% em processo mesofílico. Um ajuste polinomial foi realizado para avaliar a produção específica de metano, que variou de 379 mL CH4.h-1 a 872 mL CH4.h-1 e atividade metanogênica de 0,33 mmol CH4.gSVT-1 h-1 a 0,77 mmol CH4.gSVT-1 h-1. Para a etapa da sulfetogênese, o pH afetou consideravelmente o desempenho das arqueas metanogênicas, ocorrendo inibição mais acentuada para o pH 7,5. Na concentração mais baixa testada, de 50 mg S2-.L-1, foi observada inibição de 31,85% para pH 7,0 e de 67% para pH 7,5 e para a concentração mais elevada de 1000 mg S2-.L-1 a inibição foi de 59,75% e de 94,07% respectivamente. Na última etapa da acidogênese, maiores concentrações de ácido propiônico e acético foram alcançadas em pH 5,0 e 5,5, com 1374,66 e 1477,23 mg C3H6O2.L-1 e 993,05 e 767,80 mg CH3COOH.L-1. Maiores taxas de produção de AGV ocorreram em pH 6,5, alcançando para o ácido propiônico 8,82 mmol.d-1 gSVT-1 e 7,99 mmol.d-1 gSVT-1 para ácido acético. A produção acumulada de metano nas primeiras 60 horas atingiu 2210 mL, 5300 mL, 7210 mL e 7620 mL CH4, respectivamente para pH 5,0, 5,5, 6,0 e / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2017-07-12T18:44:50Z No. of bitstreams: 1 Dissertacao Vanessa Verona Peruzzo.pdf: 3017795 bytes, checksum: 5aad4de95a823b85afe45b94c6cd1fc0 (MD5) / Made available in DSpace on 2017-07-12T18:44:50Z (GMT). No. of bitstreams: 1 Dissertacao Vanessa Verona Peruzzo.pdf: 3017795 bytes, checksum: 5aad4de95a823b85afe45b94c6cd1fc0 (MD5) Previous issue date: 2017-07-12 / Centro de Pesquisa e Desenvolvimento Leopoldo Américo Miguêz de Mello, CENPES. / The vinasse, wastewater of the process, presents in its composition a COD of 20 to 100 g COD.L-1 and an excellent biogas production potential through anaerobic digestion. To evaluate the biogas production capacity, experiments were carried out under the gradual effect of organic volumetric load (OVL) and A/M ratio, evaluating the methanogenic step. Considering that sulfuric acid is added to the ethanol production process to prevent bacterial contamination, the interference of the addition of different sulfide concentrations in the process at pH 7.0 and 7.5 was evaluated. The fermenter was fed with Na2S.9H2O, varying the concentration of the S2- ion from 0 to 1000 mg.L-1. In order to obtain good efficiency in the production of methane, the acidogenic step was also evaluated. For this, the same concentrations of biomass and substrate were maintained, however, the pH to was adjusted 5.0, 5.5, 6.0 and 6.5. In the methanogenic stage a satisfactory reduction of the organic load present in the vinasse was achieved, with removal efficiency in the range of 82.0% and 90.3% for mesophilic process. A polynomial fit was performed to evaluate the specific production of methane, ranging from 379 mL CH4.h-1 to 872 mL CH4.h-1 and a methanogenic activity of 0.33 mmol CH4.gSVT-1 h-1 at 0.77 mmol CH4.g SVT-1 h-1. For the sulfetogenic stage, the pH considerably affected the performance of the methanogenic archaea, with a more pronounced inhibition at pH 7.5. The lowest concentration tested, 50 mg S2-.L-1, resulted in an inhibition of 31.85% inhibition pH 7.0 and 67% at pH 7.5. The highest concentration, 1000 mg S2-.L-1, the inhibition was 59.75% and 94.07% respectively. Higher concentrations of propionic and acetic acid were reached at pH 5.0 and 5.5, with 1374.66 and 1477.23 mg C3H6O2.L-1 and 993.05 and 767.80 mg CH3COOH.L-1. Higher rates of VFA production occurred at pH 6.5, yielding 8.82 mmol.d-1 gSVT-1 and 7.99 mmol.d-1 gSVT-1 for acetic acid for propionic acid. Cumulative methane production in the first 60 hours increased 2210 mL, 5300 mL, 7210 mL and 7620 mL CH4, respectively to pH 5.0, 5.5, 6.0 and 6.5.
169

Estudo da acidogênese e metanogênese aplicada no tratamento da vinhaça da cana-de-açúcar

Peruzzo, Vanessa Verona 22 June 2017 (has links)
A vinhaça, água residuária do processo, apresenta em sua composição DQO de 20 a 100 g DQO.L-1 e um ótimo potencial de produção de biogás por meio da digestão anaeróbia. Para avaliar a capacidade de produção de biogás, foram realizados experimentos sob o efeito gradual da carga orgânica volumétrica (COV) e da relação A/M, avaliando a etapa metanogênica. Como no processo de fabricação do etanol é adicionado ácido sulfúrico para evitar a contaminação bacteriana, foi avaliado a interferência da adição de diferentes concentrações de sulfetos no processo em valore de pH 7,0 e 7,5. O fermentador foi alimentado com Na2S.9H2O, variando a concentração do íon S2- de 0 a 1000 mg.L-1. Para obter uma boa eficiência na produção de metano, a etapa acidogênica também foi avaliada. Para isso, se manteve as mesmas concentrações de biomassa e substrato, porém, ajustando os valores de pH em 5,0, 5,5, 6,0 e 6,5. Na etapa metanogênica uma satisfatória redução da elevada carga orgânica presente na vinhaça foi alcançada, com eficiência de remoção entre 82,0% e 90,3% em processo mesofílico. Um ajuste polinomial foi realizado para avaliar a produção específica de metano, que variou de 379 mL CH4.h-1 a 872 mL CH4.h-1 e atividade metanogênica de 0,33 mmol CH4.gSVT-1 h-1 a 0,77 mmol CH4.gSVT-1 h-1. Para a etapa da sulfetogênese, o pH afetou consideravelmente o desempenho das arqueas metanogênicas, ocorrendo inibição mais acentuada para o pH 7,5. Na concentração mais baixa testada, de 50 mg S2-.L-1, foi observada inibição de 31,85% para pH 7,0 e de 67% para pH 7,5 e para a concentração mais elevada de 1000 mg S2-.L-1 a inibição foi de 59,75% e de 94,07% respectivamente. Na última etapa da acidogênese, maiores concentrações de ácido propiônico e acético foram alcançadas em pH 5,0 e 5,5, com 1374,66 e 1477,23 mg C3H6O2.L-1 e 993,05 e 767,80 mg CH3COOH.L-1. Maiores taxas de produção de AGV ocorreram em pH 6,5, alcançando para o ácido propiônico 8,82 mmol.d-1 gSVT-1 e 7,99 mmol.d-1 gSVT-1 para ácido acético. A produção acumulada de metano nas primeiras 60 horas atingiu 2210 mL, 5300 mL, 7210 mL e 7620 mL CH4, respectivamente para pH 5,0, 5,5, 6,0 e / Centro de Pesquisa e Desenvolvimento Leopoldo Américo Miguêz de Mello, CENPES. / The vinasse, wastewater of the process, presents in its composition a COD of 20 to 100 g COD.L-1 and an excellent biogas production potential through anaerobic digestion. To evaluate the biogas production capacity, experiments were carried out under the gradual effect of organic volumetric load (OVL) and A/M ratio, evaluating the methanogenic step. Considering that sulfuric acid is added to the ethanol production process to prevent bacterial contamination, the interference of the addition of different sulfide concentrations in the process at pH 7.0 and 7.5 was evaluated. The fermenter was fed with Na2S.9H2O, varying the concentration of the S2- ion from 0 to 1000 mg.L-1. In order to obtain good efficiency in the production of methane, the acidogenic step was also evaluated. For this, the same concentrations of biomass and substrate were maintained, however, the pH to was adjusted 5.0, 5.5, 6.0 and 6.5. In the methanogenic stage a satisfactory reduction of the organic load present in the vinasse was achieved, with removal efficiency in the range of 82.0% and 90.3% for mesophilic process. A polynomial fit was performed to evaluate the specific production of methane, ranging from 379 mL CH4.h-1 to 872 mL CH4.h-1 and a methanogenic activity of 0.33 mmol CH4.gSVT-1 h-1 at 0.77 mmol CH4.g SVT-1 h-1. For the sulfetogenic stage, the pH considerably affected the performance of the methanogenic archaea, with a more pronounced inhibition at pH 7.5. The lowest concentration tested, 50 mg S2-.L-1, resulted in an inhibition of 31.85% inhibition pH 7.0 and 67% at pH 7.5. The highest concentration, 1000 mg S2-.L-1, the inhibition was 59.75% and 94.07% respectively. Higher concentrations of propionic and acetic acid were reached at pH 5.0 and 5.5, with 1374.66 and 1477.23 mg C3H6O2.L-1 and 993.05 and 767.80 mg CH3COOH.L-1. Higher rates of VFA production occurred at pH 6.5, yielding 8.82 mmol.d-1 gSVT-1 and 7.99 mmol.d-1 gSVT-1 for acetic acid for propionic acid. Cumulative methane production in the first 60 hours increased 2210 mL, 5300 mL, 7210 mL and 7620 mL CH4, respectively to pH 5.0, 5.5, 6.0 and 6.5.
170

Taxas metabólicas de repouso e pós-prandiais em serpentes do gênero Bothrops, com ênfase nos aspectos ontogenéticos e filogenéticos (Crotalinae) / Standard metabolic rates and specific dynamic action in Bothrops with emphasis on ontogenetic and phylogenetic features (Crotalinae)

Daniel Rodrigues Stuginski 13 June 2014 (has links)
Os viperídeos estão entre as serpentes de menor custo energético de manutenção, o que é, geralmente, relacionado a seus baixos níveis de deslocamento e a tática de forrageio por emboscada. Dois importantes componentes do alocamento energético destes animais são: 1) o metabolismo de repouso padrão, que está relacionado ao custo de manutenção visceral durante o repouso e 2) o aumento metabólico pós-prandial (AMPP), que está relacionado ao custo do processo digestório. O presente trabalho teve como objetivos estudar as variações da TMRP (taxa metabólica de repouso padrão) e do AMPP em 5 espécies pertencentes ao gênero Bothrops levando em conta aspectos filogenéticos, ontogenéticos e testando hipóteses acerca de possíveis variações destes componentes em função de características ecológicas. Além disso, o presente trabalho testou, através de ferramentas de ponderação filogenética, a hipótese atualmente aceita que prediz que as TMRPs em serpentes estão essencialmente ligadas a estratégia alimentar e não a filogenia. O trabalho está dividido em quatro capítulos, sendo o primeiro devotado a uma introdução geral acerca dos assuntos que serão abordados nos demais. Os resultados e discussões específicas estão divididos em dois capítulos redigidos em forma de artigo, primeiro referente aos estudos das taxas metabólicas de repouso (capítulo 2) e o segundo sobre o AMPP (capítulo 3). Por fim, a conclusão final acerca dos achados e as perspectivas para pesquisas futuras estão presente no capítulo 4. / The viperids are among the snakes with the lowest energetic maintenance costs which are generally related to the low mobility and ambush foraging mode. Two important components of energy allocation in these animals are 1) standard metabolic rates (SMR), related to the cost of keeping visceral components during resting and 2) specific dynamic action (SDA) , which is related to the cost of digestion. The present work aimed to study the variations of SMR and SDA in 5 species of the genus Bothrops taking into account aspects of phylogeny and ontogeny plus testing hypotheses about possible variations in these metabolic rates related to ecological characteristics. Furthermore, the present study used phylogenetic weighting tools to test the currently accepted hypothesis that predicts that SMR in snakes is related to the feeding strategy and not to phylogeny. The work is divided into four different chapters. Chapter 1 is devoted to a general introduction about the issues that will be addressed in the others chapters. The results and discussions are divided into two chapters presented as articles, the first referring to studies of SMR ( chapter 2 ) and the second to the SDA (chapter 3 ). Finally, in chapter 4 we include the final conclusion and prospects for future research

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