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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.
331

A preliminary ecological survey of a temporary pond in a Douglas fir forest association with emphasis on the food and feeding habits of the Oregon newt, Triturus granulosus granulosus

Kelly, Robert W. 06 1900 (has links)
55 pages / This work has been done as a preliminary ecological survey of an aquatic habitat in a Douglas fir forest association. Since this is a preliminary study it is not expected to be complete in all details affecting the associations within a community. Little work of this type has been conducted previously, and much more work should be done along these lines in order to have a more complete understanding of the ecology of this, or a similar area. Perhaps this work will be of less value in itself than the assistance it may afford others who are beginning similar undertakings. In this work an attempt has been made to point out many of the physical factors which have an influence on, or directly affect the community, e.g., the size of the pond, the location, depth, etc. A descriptive account will be given of the flora and fauna, and an attempt has been made to present the interrelations between the organisms and their environment.
332

Síntese otimizada de sistemas de cogeração e dessalinização

Ferreira, Eduardo Manfredini [UNESP] 05 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-05Bitstream added on 2014-06-13T20:46:41Z : No. of bitstreams: 1 ferreira_em_dr_guara_prot.pdf: 2582379 bytes, checksum: 9263a659ae78b3b2a0dfd7500e38a270 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A escassez da disponibilidade de água doce no mundo torna-se preocupante para os próximos anos e, apesar da crescente divulgação de tal situação, são poucas as pessoas que, na prática adotam uma postura consciente acerca da economia e uso racional do bem natural mais precioso existente. A presente tese apresenta uma proposta de produção de água potável a partir da água do mar pelo uso de processos de dessalinização associados a processos de cogeração, para que produzama energia térmica e elétrica para o funcionamento da instalação. A mesma é analisada com o uso de diferentes configurações, com vistas à otimização da instalação. São analisados 4 casos, verificando-se a viabilidade de sistemas de duplo propósito e sistemas híbridos, considerando-se, pelo lado do sistema de cogeração, a disputa entre diferentes conjuntos a gás de produção comercial, queimando gás natural ou biomassa gaseificada, com geradores de vapor, queimando óleo combustível ou biomassa in natura; pelo lado do sistema de dessalinização, concorrem unidades de osmose reversa acionadas térmica (ORS) ou eletricamente (ORE), unidades de evaporação (MED) e de destilação (MSF); no atendimento ás necessidades de vapor concorrem turbinas de contrapressão e condensação/extração. Foram analisados dados referentes à cidade litorânea de Ubatuba, SP, para avaliação do atendimento conjunto das necessidades de energia elétrica ee água potável para o abastecimento de situações limítrofes, como ocorre durante os picos de consumo de verão. Conclui-se que a proposta é viável para os casos analisados, podendo haver a possibilidade de venda de excedente energético, de acordo com o nível de produção da unidade como um todo. / World's fresh water availability scarcity is becoming a concerning problem day by day, and depende the increasing of the alarming new about such situation, just a few people adopt a positive position about the economy and rational use os this precious natural resource. This thesis presents a fresh water production proposal from seawater by desalination processes associated to cogeneration processes for producing the necessary thermal and electric energy for the whole installation. The dual-purpose systems is analyzed with the use of differente configurations by an optimization viewpoint. Four cases are analyzed with hybrid and dua purpose systems availability verification. The considerations, with respect to cogeneration were the use different commercial gas turbines, burning natural gas or gasified biomass, with or without steam generator, burning fuel oil or biomass in natura. For desalination system, it wasallowed the choice of reverse osmosi thermally driven (ROS) reverse osmosis elctrically driven (ROE), evaporation (MED) and distillation (MSF) units. Also, the steam supply system could be constituted of backpressure and extraction-condensation turbines. The data analyzed here refers to the Ubatuba coastal city, situated in the São Paulo Statte - Brazil, the relationship between the electrical energy and fresh water simultaneous supplying for extrem situations, like it occurs during summer consumption peaks was analyzed. The present study concluded that the analyzed cases were feasible, with the possibility of energetic surplus selling, according to the unit production operational level.
333

Aspectos estruturais do hepatopâncreas do camarão de água doce Macrobracium amazonicum (Heller, 1862)

Marques Junior, Julio [UNESP] 10 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-10Bitstream added on 2014-06-13T20:48:50Z : No. of bitstreams: 1 marquesjr_j_me_jabo.pdf: 1623958 bytes, checksum: de1f1ad20d0fe345b555ffda9c9b102d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O hepatopâncreas está associado ao intestino médio e apresenta diferentes níveis de complexidade dentre as espécies de decápodas. O objetivo deste estudo foi descrever a estrutura histológica do hepatopâncreas de Macrobrachium amazonicum descrevendo características macroscópicas e microscópicas, tais como os tipos celulares que o compõe e a organização de seus túbulos secretores. Adultos de ambos os sexos de M. amazonicum foram coletados, e o hepatopâncreas foi estudado usando-se técnicas histológicas. O hepatopâncreas é um órgão de coloração amarelo-acastanhada, organizado em dois lobos laterais. A estrutura é formada por uma massa de túbulos de fundo cego com espaço intertubular escasso. Cada túbulo secreto r consiste de um epitélio circundado por lâmina basal e células mioepiteliais. Cinco tipos celulares foram observados: célula E (indiferenciada), célula F (fibrilar), célula R (reabsortiva), célula B (vesicular) e célula M (basal). As células E foram observadas na porção distal dos túbulos e são responsáveis pela reposição mitótica das células do epitélio. As células F foram observadas principalmente próximas às células E na região distal. Células R foram observadas ao longo de todo o túbulo secretor, principalmente nas regiões proximal e medial. As células B são abundantes nas regiões medial e distal do túbulo, diminuindo sua freqüência na região proximal. Foram observadas células M ao longo de todo o túbulo secretor, associadas às células R. / The aim of this study is to describe the histological structure of the hepatopancreas of Macrobrachium amazonicum, describing macroscopic and microscopic characteristics: cellular types and the organizations of the secretory tubules. Adults of both sexes of M. amazonicum were collected and the hepatopancreas was studied by using histological techniques. The hepatopancreas is a bilaterally bilobed brown-yellowish organ. The structure is formed by a mass of blind tubules, with scarce intertubular space. Each tubule consist of a cylindrical epithelial layers surrounded by a basal lamina and myoepithelial cells. Five cellular types were recognized: E-cells (embryonic), E-¬cells (fibrilar), B-cells (blisterlike), R-cells (resorptive) and M-cells (midget). F-¬cells were observed in the distal end of the secretory tubules and are the mitotic cells that replenish the cells of the epithelium. The F-cells were observed along all the tubule, mainly in the distal region next the E-cells. R-cells were observed in the proximal and medial regions. The B-cells were abundant in the medial and distal regions of the tubule. M-cells were observed along all the tubule associated to the R-cells.
334

Estudo dos efeitos ecotoxicológicos dos fármacos paracetamol e dipirona sódica para organismos aquáticos / Ecotoxicological study of effects of the pharmaceuticals dipyrone sodium and paracetamol to aquatic organisms

LAMEIRA, VANESSA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:32Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:01Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
335

Síntese otimizada de sistemas de cogeração e dessalinização /

Ferreira, Eduardo Manfredini. January 2008 (has links)
Resumo: A escassez da disponibilidade de água doce no mundo torna-se preocupante para os próximos anos e, apesar da crescente divulgação de tal situação, são poucas as pessoas que, na prática adotam uma postura consciente acerca da economia e uso racional do bem natural mais precioso existente. A presente tese apresenta uma proposta de produção de água potável a partir da água do mar pelo uso de processos de dessalinização associados a processos de cogeração, para que produzama energia térmica e elétrica para o funcionamento da instalação. A mesma é analisada com o uso de diferentes configurações, com vistas à otimização da instalação. São analisados 4 casos, verificando-se a viabilidade de sistemas de duplo propósito e sistemas híbridos, considerando-se, pelo lado do sistema de cogeração, a disputa entre diferentes conjuntos a gás de produção comercial, queimando gás natural ou biomassa gaseificada, com geradores de vapor, queimando óleo combustível ou biomassa in natura; pelo lado do sistema de dessalinização, concorrem unidades de osmose reversa acionadas térmica (ORS) ou eletricamente (ORE), unidades de evaporação (MED) e de destilação (MSF); no atendimento ás necessidades de vapor concorrem turbinas de contrapressão e condensação/extração. Foram analisados dados referentes à cidade litorânea de Ubatuba, SP, para avaliação do atendimento conjunto das necessidades de energia elétrica ee água potável para o abastecimento de situações limítrofes, como ocorre durante os picos de consumo de verão. Conclui-se que a proposta é viável para os casos analisados, podendo haver a possibilidade de venda de excedente energético, de acordo com o nível de produção da unidade como um todo. / Abstract: World's fresh water availability scarcity is becoming a concerning problem day by day, and depende the increasing of the alarming new about such situation, just a few people adopt a positive position about the economy and rational use os this precious natural resource. This thesis presents a fresh water production proposal from seawater by desalination processes associated to cogeneration processes for producing the necessary thermal and electric energy for the whole installation. The dual-purpose systems is analyzed with the use of differente configurations by an optimization viewpoint. Four cases are analyzed with hybrid and dua purpose systems availability verification. The considerations, with respect to cogeneration were the use different commercial gas turbines, burning natural gas or gasified biomass, with or without steam generator, burning fuel oil or biomass in natura. For desalination system, it wasallowed the choice of reverse osmosi thermally driven (ROS) reverse osmosis elctrically driven (ROE), evaporation (MED) and distillation (MSF) units. Also, the steam supply system could be constituted of backpressure and extraction-condensation turbines. The data analyzed here refers to the Ubatuba coastal city, situated in the São Paulo Statte - Brazil, the relationship between the electrical energy and fresh water simultaneous supplying for extrem situations, like it occurs during summer consumption peaks was analyzed. The present study concluded that the analyzed cases were feasible, with the possibility of energetic surplus selling, according to the unit production operational level. / Orientador: José Antonio Perrella Balestieri / Coorientador: Mauricio Araujo Zanardi / Banca: Paulo Magalhães Filho / Banca: Ricardo Alan Verdú Ramos / Banca: Rogério José da Silva / Banca: Miguel Edgar Morales Udaeta / Doutor
336

Estudo dos efeitos ecotoxicológicos dos fármacos paracetamol e dipirona sódica para organismos aquáticos / Ecotoxicological study of effects of the pharmaceuticals dipyrone sodium and paracetamol to aquatic organisms

LAMEIRA, VANESSA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:32Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:01Z (GMT). No. of bitstreams: 0 / O presente estudo avaliou os efeitos letais e subletais de dipirona sódica e paracetamol para organismos de água doce. O efeito letal foi determinado pela realização de ensaios agudos com D. similis, C. dubia, C. silvestrii e D. rerio. A influência da temperatura, tipo de água de diluição e fotoperíodo na ecotoxicidade aguda foram avaliadas. Os efeitos subletais foram determinados por meio de ensaios de embrioxicidade com D. similis (20°C), crônicos individuais e populacionais com D. similis, C. dubia e C. silvestrii. A influência da temperatura na ecotoxicidade crônica individual e populacional foi determinada. Os critérios para aceitabilidade para o controle (número de neonatas) nos ensaios populacionais com D. simlis (20 e 25°C) e C. dubia, foram estabelecidos. Nos ensaios de ecotoxicidade aguda, D. similis (20°C) foi mais sensível a dipirona sódica que a 25°C e, para paracetamol, D. similis (25°C) foi mais sensível. A água de diluição influenciou na ecotoxicidade aguda apenas do paracetamol e o fotoperíodo não influenciou na ecotoxicidade aguda de ambos os fármacos. Os valores de CL(I);96H obtidos para D. rerio foram 3670 e 590mg.L-1 para dipirona sódica e paracetamol, respectivamente. Dipirona sódica e paracetamol induziram malformações nas neonatas e embriões de D. similis e os valores de CI50 obtidos foram 21,1 e 94,00mg.L-1, respectivamente. Os valores de CI50 nos ensaios crônicos individuais com dipirona sódica para D. similis (20°C e 25°C) foram 7,53mg.L e 8,08mg.L-1, respectivamente. Para C. dubia e C. silvestrii a CI50 para ensaios crônicos individuais com dipirona sódica foram 5,38 e 3,57mg.L-1, respectivamente. Nos ensaios crônicos individuais com paracetamol, a CI50 para D. similis (20°C) foi 21,84mg.L-1 e 10,72mg.L-1 para D. similis (25°C). Para C. dubia e C. silvestrii a CI50 nos ensaios crônicos individuais com paracetamol foram 7,24 e 4,15mg.L-1, respectivamente. Como critérios de aceitabilidade para os ensaios crônicos populacionais estabeleceu-se para o controle de D. similis (20 e 25°C) e C. dubia 137, 143 e 80 neonatas, respectivamente. Os valores de CI50 nos ensaios populacionais com D. similis (20 e 25°C), C. dubia e C. silvestrii para dipirona sódica foram 8,84, 10,82, 4,68 e 2,81mg.L-1, respectivamente. Para os ensaios populacionais com paracetamol os valores de CI50 para D. similis (20 e 25°C), C. dubia e C. silvestrii foram 9,57, 10,1, 6,48 e 4,26mg.L-1, respectivamente. Os valores das concentrações que causaram ecotoxicidade aguda e crônica não são superiores as concentrações destes compostos no ambiente porém, de acordo com a classificação baseada na Diretiva Européia 93/67/EEC, estes compostos são classificados como nocivos para o ambiente. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
337

The biomass and activity of bacteria in the sediments of Marion Lake, British Columbia

Perry, E. A. January 1974 (has links)
Two biomass indicators (direct counts and ATP analysis) and two activity estimators (glucose uptake and dehydrogenase activity) were used to study the bacteria at 1 m water depth in Marlon Lake sediments. Direct count-biomass estimates for bacteria averaged 0.6l gC/m², were high in summer, declined rapidly in fall, then increased during the winter. Microorganisms less than approximately 30 μm diameter had a mean biomass of 1.28 gC/m² as measured by ATP analysis. Seasonal variations in this figure paralleled changes in the algal population, although algal contributions to the microbial biomass were less than 50 per cent. ATP analysis was also used to estimate the biomass of the sediment community, excluding animals greater than approximately 5 mm in length. The mean community biomass was 4.69 gC/m². Comparison of ATP data with enumeration data obtained by others, suggests that ATP is a good biomass indicator, except when cellular ATP levels are changed in reaction to biotic or abiotic environmental factors. It is proposed that, in situations such as intense grazing or rapid Increases or decreases in temperature, ATP measurements reflect not only biomass but also activity. At such times ATP-biomass data may Indicate biomass potential, or the capacity of the population to maintain its biomass under abnormally high rates of loss. Dehydrogenase activity, or respiratory potential, of the sediment bacteria was assayed using trlphenyl tetrazolium chloride. The estimate for annual rate of carbon loss as CO2 from the bacterial population (19.3 g C/m²•year), was almost identical to previously reported data obtained by measuring oxygen consumption in normal and antibiotic-treated sediment cores. Uptake of ¹⁴C-glucose was determined in mixed, diluted sediments. The maximum uptake rate (9.6 g C/m².year), natural uptake rate (5.3 S C/m².year) and the natural turnover time (0.31 h) were similar to previous data for these sediments. This suggests that, at least in terms of function, the bacterial population is quite stable from year to year. Biomass and activity of the Marion Lake sediment bacteria were found to be in phase in late spring through early fall, but activity remained low in winter despite Increases in the microbial biomass, and increased much more rapidly than biomass in early spring. The dynamics of the bacterial population are discussed in terms of these relationships. The size of the algal and bacterial populations and organic matter reservoirs, and the flux rates for carbon between these compartments are summarized. / Science, Faculty of / Zoology, Department of / Graduate
338

Modeling trihalomethane formation in bromide-containing surface water undergoing conventional treatment

Smith, Maureen McBride 01 January 1993 (has links)
No description available.
339

In vitro and in vivo effects of chemotherapeutants on the oyster parasite, Perkinsus marinus

Calvo, Gustavo W. 01 January 1994 (has links)
To investigate the potential of chemotherapeutants to control the oyster pathogen Perkinsus marinus, anticoccidial and antifungal compounds were tested in vitro on infected hemolymph and cultured P. marinus cells and in vivo on infected oysters. In addition, acute toxicity to oysters was determined for six anticoccidials. In vitro experiments with infected hemolymph consisted of 24 h exposure of 0.2 mL hemolymph aliquots to concentrations ranging from 100 mg/L to 0.01 mg/L of amphotericin-B, amprolium, arprinocid, cycloheximide, lasalocid, malachite green, monensin, sulfadimethoxine, and a potentiated sulfadimethoxine, followed by incubation in fluid thioglycollate medium (FTM) to determine prezoosporangia abundance. Lasalocid, malachite green, and amphotericin-B were the most effective compounds reducing prezoosporangia abundance, relative to the untreated control group, at concentrations as low as 10 mg/L. Cycloheximide, monensin, and to a lesser extent sulfadimethoxine, were also effective but only at the highest concentration tested (100 mg/L). In vitro experiments with cultured P. marinus consisted of 24 h exposure of 10&\sp5& cells to 100 mg/L, 10 mg/L, and 1 mg/L of amphotericin-B, and 100 mg/L of cimetidine, cycloheximide, fumagillin, 5-fluorocytosine, ketoconazole, lasalocid, and monensin, followed either by incubation in FTM to determine abundance and size of prezoosporangia, or by addition of Neutral Red to determine cell viability. Amphotericin-B, lasalocid, and monensin were effective in reducing prezoosporangia abundance, size, and/or cell viability. No effects of cycloheximide on cultured cells were apparent. Lasalocid, monensin, and malachite green, were toxic to oysters at concentrations below 10 mg/L. The 96-hr. LC50 for lasalocid was 0.59 mg/L. No median lethal dose was determined for monensin or malachite green, but oyster mortality resulted from exposures ranging from 1 mg/L to 10 mg/L of either compound. In three in vivo experiments, infected oysters were exposed to amprolium, arprinocid, cycloheximide, lasalocid, monensin, malachite green, potentiated sulfadimethoxine, and sulfadimethoxine at various concentrations. Only cycloheximide was effective in reducing P. marinus infections. After 15 days of exposure to 10 mg/L of cycloheximide, weighted prevalence significantly declined from 3.78 in untreated controls to 2.10 in treated oysters. Infections progressed after treatment was discontinued as indicated by an increase in weighted prevalence from 0.71 at the end of treatment to 1.31 one month later. (Abstract shortened by UMI.).
340

The Ecological Significance of a Ctenophore, Mnemiopsis leidyi (A. Aggasiz), in a Fish Nursery Ground

Burrell, Victor G. 01 January 1968 (has links)
No description available.

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