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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

Synthesis of novel triglycerides from mackerel by-products and vegetable oils

Zuta, Charles Prince January 2003 (has links)
No description available.
242

Fluorescence Based Approach to Drinking Water Treatment Plant Natural Organic Matter (NOM) Characterization, Treatment, and Management

Sanchez Morcote, Nancy Pilar 15 May 2013 (has links)
No description available.
243

Material av restprodukter från hampa till produktdesign / Material of By-Products FromHemp for Product Design

Gezavati, Daniel January 2023 (has links)
This paper is a research through design that answers the question: How can the by-products from hemp production be utilized to create a sustainable material for product design?Hemp is the commercial crop that sequesters carbon dioxide most effectively in the world, but large amounts of bast fibers and hurd emerge as by-products ater cultivation for seeds, flowers, and leaves. These by-products can be difficult for farmers to manage as they require space for storage and often must undergo a lengthy production process before they can be converted into products. The by-products of the hemp industry must be managed properly in order for the whole production chain to be considered sustainable.This paper explores theories like Upcycling and Design for Sustainable Development, so sustainability is always considered while managing these by-products. The research methodology encompasses interviewing six experts within the field of product design and hemp to comprehend the perceived difficulties and possible soultions. Material mapping, user tests and material tests are performed to develop a material from hemp fibres and stoneware clay. Additional user tests, market analysis, requirement list,braindrawing and prototypes are then implemented to ascertain what products that could be made from the hemp clay and how these shall be designed. These methods resulted in the contribution of design for the paper: HampaLampa (HempLamp), a hemp-lampfoot made with hemp clay and linseed oil paint as a surface treatment. / Studien är en forskning genom design som besvarar frågeställningen: Hur kan restprodukter från hampaproduktionen utnyttjas för att skapa ett hållbart material till produktdesign? Hampa är den komersiella grödan som absorberar koldioxid mest effektivt i världen, men det uppstår stora mängder restprodukter i form av fibrer och vedämnen när hampa odlas med frön, blommor eller blad som primärprodukt. Dessa restprodukter är svåra för lantbrukare att hantera då de tar stor plats att lagra och ofta behöver genomgå en lång tillverkningsprocess för att kunna användas i produkter. Hampaindustrins restprodukter behöver hanteras för att produktionskedjan skall förbli hållbar. Studien utforskar teorier som upcycling och design för hållbar utveckling, hållbarhet prioriteras ständigt när processen att använda restprodukterna utforskas. I Metodkapitlet intervjuas sex experter inom produktdesign och hampa för att inse vilka svårigheter och möjliga lösningar de känner till. Materialkartläggning, användartester och materialtester utförs för att utveckla ett material från hampafibrerna och stengodslera. Ytterliggare användartester, marknadsanalys, kravlista, braindrawing och prototyperutförs sedan för att utforska vilka produktersom hade kunnat skapas av hampalera och hur dessaskallutformas. Dessa metoder resulterade i designbidragetförstudien: HampaLampa, en hampa-lampfot skapad av hampalera med en ytbehandling av linoljefärg.
244

Genotoxicity of haloacetic acids, aspirin and ibuprofen in human cells. Genotoxic effects of water disinfectant- by-products in human blood and sperm and bulk and nano forms of aspirin and ibuprofen in human blood of respiratory disease patients

Ali, Aftab H.M. January 2014 (has links)
This project focuses on two important topics which may pose hazards to human health. Firstly, drinking water disinfection by-products (DBPs), which are generated by the chemical disinfection of water have been investigated. What has not been shown is the effect of DBPs in human germ cells as well as somatic cells and whether oxidative stress is involved in the mechanism of genotoxic action. Three different DBPs (halo acetic acids: HAAs), together with the antioxidants – catalase and butylated hydroxyanisole (BHA), were investigated in peripheral blood cells and sperm from healthy individuals using the Comet assay and lymphocytes only using the micronucleus assay. Secondly, nanoparticles of the non-steroidal anti-inflammatory drugs (NSAIDs), aspirin and ibuprofen, have been investigated in patients with respiratory diseases, in the micronucleus assay and the Comet repair assay. NSAIDs inhibit cyclooxygenase enzyme activity, which plays part in tumour progression. In the Comet assay, BHA and catalase were able to reduce DNA damage in both cell types compared to HAAs alone. Similarly, in the micronucleus assay, micronuclei were reduced with the antioxidants, suggesting oxygen radical involvement in both assays. With the NSAIDs, reductions were seen for DNA damage in the micronucleus assay with aspirin and ibuprofen nanoparticles compared to their bulk forms. Using the Comet repair assay, aspirin and ibuprofen nanoparticles aided repair of DNA to a greater extent than their bulk counterparts, which in turn showed better repair compared to samples repaired without NSAIDs. These observations show the importance of DBPs and NSAIDs in genotoxic public health issues. / United Kingdom India Education and Research Initiative (UKIERI).
245

Formation Of Iodinated Disinfection By-Products From Iodinated X-ray Contrast Media, Iopamidol, In The Presence Of Nom And Chlorinated Oxidants

Crafton, Elizabeth Ann January 2014 (has links)
No description available.
246

Sorption of selected inorganic materials on raw and retorted oil shales

Cowher, Donna M. January 1984 (has links)
Shale oil is an attractive, alternative fuel source for a world in which there is an increasing demand for energy. However, it is necessary to assess the environmental impacts of the shale oil industry before widescale production is begun. Diversity of retorting processes, the subsequent variability in waste products and the possible waste management schemes makes assessment of these impacts complicated. Waste treatment and disposal are areas which must be researched thoroughly. To properly evaluate the environmental risks associated with the disposal of processed shales and process wastewaters, an appreciation for the sorption/desorption (S/D) characteristics of oil shales is required. The overall objective of this research was to evaluate the S/D capacity of four types of shale: Antrim (spent, eastern shale), Anvil (raw, western shale), Oxy 6 and Run 16 (spent, western shales). Batch and continuous-flow, column experiments were performed in which the S/D behavior of five cations (As, Ca, Cd, Fe, and K) and three anions (F, SO₄, and HCO₃/CO₃) was monitored. The conductivity, redox potential, and pH of the eluent fluids were also determined. This study showed that retort temperature and porosity of the various shales had a significant effect an their S/D characteristics. Batch elution trials with spent shales produced eluents having a characteristic pH in the range 8.5 to 11.5. In these experiments, the shales retorted at lower temperatures (660°C and 793°C) released higher levels of Ca, K, and SO₄ than did a higher temperature, retorted shale (800 to 1000°C) and raw shale. The shales retorted at lower temperatures also had the highest porosities of the four shales and exhibited a greater capacity for sorption of As and F than did the other shales. Continuous-flow, elution trials showed that most inorganics monitored were flushed from the columns of shale in the first 5 to 8 pore volumes of effluent. / Master of Science
247

Utilization of crab processing waste and chitin associated with the waste as feed for ruminants

Ayangbile, Gbemiga A. January 1989 (has links)
Four experiments were conducted with crab processing waste. Addition of 1.5% propionic/formic acid prevented degradation up to 14 d. Desirable fermentation was achieved when 32% of the treated crab waste was ensiled with 32% straw, 16% molasses, and 20% water with or without .1% microbial inoculant. The pH of the silage was lowered and high concentration of lactic acid was observed. Use of .2% NaOCl or .4% H₂O₂ retarded spoilage of crab processing waste up to 7 d. Ensiling of the treated waste (32%), straw (32%), molasses (16%), and H₂0 (20%) indicated that the chemical used in preservation enhanced fermentation. Addition of .4% NaOCl and 1.5% acetic acid to the crab processing waste retarded degradation up to d 4. The trimethylamine (TMA) concentration and NH₃ evolution were highest for the untreated waste while the lowest concentration for TMA and NH₃ evolution were observed for the NaOH-treated waste. Addition of 1% NaNO₂ or combination of .4% NaOCl/CaOCl (1:1, w/w) preserved the waste for up to 10 d. The evolution of NH₃ and H2₂S, and TMA concentration were lowest for the waste treated with 1% NaNO₂. Apparent digestibility of DM, organic matter, CP, energy, NDF, ADF, cellulose and hemicellulose decreased linearly (P<.01) with level of crab waste-straw silage in diets containing 0, 50, and 100% crab waste-straw silage. Nitrogen retention increased linearly (P<.05) with level of crab waste-straw silage. The apparent absorption was higher (P<.01) and retention was positive (P<.05) for Ca, Mg, Na, K, Cu and Fe with sheep fed the highest level of crab waste-straw silage. Daily gain, feed efficiency and carcass characteristics tended to be higher for steers fed 30% crab waste-straw silage, dry basis. The flavor and overall desirability of cooked meat were not adversely affected by feeding up to 30% crab waste-straw silage, dry basis. Modifying the existing methods of quantifying chitin showed that initial decalcification or deprotinization of the samples with chemicals are not necessary. Similar values were obtained for chitin when ADF/ashing method was compared to the ADF/deacetylation method. These methods prevented loss of chitin during preparation. Digestibility of chitin was higher (58%) for sheep fed 100% crab waste-straw silage compared to the value of 37% in sheep fed 50% crab waste-straw silage. When ADF/ashing method was used in quantifying chitin, higher disappearances were obtained for samples containing 100% crab meal kept in the rumen or incubated in vitro for 72 h. / Ph. D.
248

Studies of methods of preserving and enhancing fermentation, nutritional value and palatability of seafood waste for feeding ruminants

Abazinge, Michael D. A. January 1986 (has links)
Ph. D. / incomplete_metadata
249

Modelagem numérica e análise probabilística da pluma de contaminação do lixão de São Pedro da Aldeia / Numerical model and analysis probabilistic of propagation of contamination plume from landfill of São Pedro da Aldeia

Maria Georgina Muniz Washington 14 February 2008 (has links)
O objetivo do trabalho é aplicar um modelo numérico que simule a propagação da pluma de contaminação derivada de chorume, como ferramenta numérica que permita uma análise dos parâmetros envolvidos no sistema, tendo como caso de estudo o lixão de São Pedro da Aldeia, levando em conta: o mecanismo de perda de massa durante o transporte e a variabilidade estatística dos principais parâmetros de entrada (input) no modelo numérico. A perda de massa durante o fluxo pode ocorrer tanto por sorção, como por decaimento microbiológico, será estimada através da interpretação probabilística de dados experimentais obtidos no lixão de São Pedro da Aldeia. Os resultados obtidos pela modelagem numérica serão comparados com os resultados experimentais de concentração do íon cloreto obtidos por medições em campo. Os resultados experimentais foram obtidos considerando distâncias crescentes em relação ao lixão, para oito intervalos de tempo distintos, permitindo, assim, comparar os resultados alcançados pela modelagem numérica com dados experimentais reais, obtidos em função do tempo e da distância ao lixão. Para a modelagem numérica, foi utilizada a equação diferencial do transporte advectivo-dispersivo, levando em conta um termo de perda de massa estimado a partir de interpretações estatísticas dos resultados experimentais obtidos. A solução da equação diferencial do fluxo advectivo dispersivo foi analisada pelo método dos volumes finitos, que se mostra adequado para problemas de avanço de frentes de saturação e/ou de contaminação. Para a modelagem probabilística, foi utilizado o Método de Rosenblueth (ou método das estimativas pontuais), considerando-se, como variáveis aleatórias mais relevantes: a condutividade hidráulica k, a concentração iônica inicial Co e o decaimento da concentração iônica em função da distância (x) ao lixão expresso por um termo bo em (mg/l/m). A interpretação estatística das concentrações medidas experimentalmente mostrou uma faixa de variabilidade muito bem representada pela faixa de variação obtida pela conjugação da solução da equação de transporte de contaminantes (pelo método dos volumes finitos) com análise de variabilidade por formulação FOSM (pelo método das estimativas pontuais de Rosenblueth). Os resultados obtidos indicam que, embora com a contaminação crescente, podemos avaliar com poucos dados a contaminação ao longo do tempo. As simulações indicaram coerência com o resultado obtido experimentalmente, validando assim o modelo utilizado. Entende-se que o trabalho conseguiu demonstrar a aplicabilidade e relativa praticidade no que diz respeito ao estudo do fluxo de contaminantes em meios saturados. Os resultados se mostraram satisfatórios no que tange ao entendimento das questões abordadas. / The objective of this work is to apply a numerical model that simulates the propagation of the contamination plume stemmed from leachate as a numerical tool that allows an analysis of the parameters involved in the system, having the landfill of São Pedro da Aldeia as study case. The model takes into account the loss of contaminant mass mechanism during transport and the statistical variability, in the numerical model, of the main input variables. The loss of mass during the flow, which can occur either in the form of sorption or as a microbiological decay, will be assed by probabilistic interpretation of experimental data. The results obtained by the numerical modeling will be compared to the experimental results of the ionic chloride concentration obtained by field mediations. The experimental results were obtained taking into account the growing distances in relation to the landfill, for eight different time intervals, allowing, this way, the comparison of the results reached by the numerical modeling with the real experimental data results, obtained due to the time and the distance of the landfill. For the numerical modeling, the differential equation of the advective-dispersive transport was used, taking into account a term of loss of mass estimated from statistical interpretations of the experimental results. The differential equation solution of the advective-dispersive flow was obtained by the finite volumes method, which was proved adequate to problems concerning the propagation of contaminating plumes in saturated soils. For the probabilistic modeling, the Rosenblueth Method (or point estimate method) was used, considering, as more relevant aleatory variables, the hydraulic conductivity k, the initial ionic concentration and the rate of concentration decay. The statistical interpretation of the concentrations experimentally measured showed one variability band well represented by the variation band obtained by the conjunction of the contaminant transport equation solution (finite volumes method) with the variability analysis of the FOSM formularization (Rosenblueths point estimate method). The obtained results indicate that even with the increasing contamination it is possible, with little data, to evaluate the contamination throughout time. The simulations indicated coherence with the experimentally obtained results validating, this way, the used model. The work demonstrates the applicability and the relative practicity concerning the study of the contaminant flow in saturated environments. Considering the understanding of the boarded questions, the results seemed satisfactory.
250

Modelagem numérica e análise probabilística da pluma de contaminação do lixão de São Pedro da Aldeia / Numerical model and analysis probabilistic of propagation of contamination plume from landfill of São Pedro da Aldeia

Maria Georgina Muniz Washington 14 February 2008 (has links)
O objetivo do trabalho é aplicar um modelo numérico que simule a propagação da pluma de contaminação derivada de chorume, como ferramenta numérica que permita uma análise dos parâmetros envolvidos no sistema, tendo como caso de estudo o lixão de São Pedro da Aldeia, levando em conta: o mecanismo de perda de massa durante o transporte e a variabilidade estatística dos principais parâmetros de entrada (input) no modelo numérico. A perda de massa durante o fluxo pode ocorrer tanto por sorção, como por decaimento microbiológico, será estimada através da interpretação probabilística de dados experimentais obtidos no lixão de São Pedro da Aldeia. Os resultados obtidos pela modelagem numérica serão comparados com os resultados experimentais de concentração do íon cloreto obtidos por medições em campo. Os resultados experimentais foram obtidos considerando distâncias crescentes em relação ao lixão, para oito intervalos de tempo distintos, permitindo, assim, comparar os resultados alcançados pela modelagem numérica com dados experimentais reais, obtidos em função do tempo e da distância ao lixão. Para a modelagem numérica, foi utilizada a equação diferencial do transporte advectivo-dispersivo, levando em conta um termo de perda de massa estimado a partir de interpretações estatísticas dos resultados experimentais obtidos. A solução da equação diferencial do fluxo advectivo dispersivo foi analisada pelo método dos volumes finitos, que se mostra adequado para problemas de avanço de frentes de saturação e/ou de contaminação. Para a modelagem probabilística, foi utilizado o Método de Rosenblueth (ou método das estimativas pontuais), considerando-se, como variáveis aleatórias mais relevantes: a condutividade hidráulica k, a concentração iônica inicial Co e o decaimento da concentração iônica em função da distância (x) ao lixão expresso por um termo bo em (mg/l/m). A interpretação estatística das concentrações medidas experimentalmente mostrou uma faixa de variabilidade muito bem representada pela faixa de variação obtida pela conjugação da solução da equação de transporte de contaminantes (pelo método dos volumes finitos) com análise de variabilidade por formulação FOSM (pelo método das estimativas pontuais de Rosenblueth). Os resultados obtidos indicam que, embora com a contaminação crescente, podemos avaliar com poucos dados a contaminação ao longo do tempo. As simulações indicaram coerência com o resultado obtido experimentalmente, validando assim o modelo utilizado. Entende-se que o trabalho conseguiu demonstrar a aplicabilidade e relativa praticidade no que diz respeito ao estudo do fluxo de contaminantes em meios saturados. Os resultados se mostraram satisfatórios no que tange ao entendimento das questões abordadas. / The objective of this work is to apply a numerical model that simulates the propagation of the contamination plume stemmed from leachate as a numerical tool that allows an analysis of the parameters involved in the system, having the landfill of São Pedro da Aldeia as study case. The model takes into account the loss of contaminant mass mechanism during transport and the statistical variability, in the numerical model, of the main input variables. The loss of mass during the flow, which can occur either in the form of sorption or as a microbiological decay, will be assed by probabilistic interpretation of experimental data. The results obtained by the numerical modeling will be compared to the experimental results of the ionic chloride concentration obtained by field mediations. The experimental results were obtained taking into account the growing distances in relation to the landfill, for eight different time intervals, allowing, this way, the comparison of the results reached by the numerical modeling with the real experimental data results, obtained due to the time and the distance of the landfill. For the numerical modeling, the differential equation of the advective-dispersive transport was used, taking into account a term of loss of mass estimated from statistical interpretations of the experimental results. The differential equation solution of the advective-dispersive flow was obtained by the finite volumes method, which was proved adequate to problems concerning the propagation of contaminating plumes in saturated soils. For the probabilistic modeling, the Rosenblueth Method (or point estimate method) was used, considering, as more relevant aleatory variables, the hydraulic conductivity k, the initial ionic concentration and the rate of concentration decay. The statistical interpretation of the concentrations experimentally measured showed one variability band well represented by the variation band obtained by the conjunction of the contaminant transport equation solution (finite volumes method) with the variability analysis of the FOSM formularization (Rosenblueths point estimate method). The obtained results indicate that even with the increasing contamination it is possible, with little data, to evaluate the contamination throughout time. The simulations indicated coherence with the experimentally obtained results validating, this way, the used model. The work demonstrates the applicability and the relative practicity concerning the study of the contaminant flow in saturated environments. Considering the understanding of the boarded questions, the results seemed satisfactory.

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