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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.
401

Mathematical modelling of solute transport through stratum corneum /

Mollee, Thomas. January 2005 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.
402

Atmospheric absorption models for the millimeter wave range

Kuhn, Thomas. Unknown Date (has links) (PDF)
University, Diss., 2003--Bremen.
403

Direct costing

Anderson, Ralph E. January 1960 (has links)
Thesis (M.B.A.)--Boston University / Accounting as a profession has made outstanding progress up through the mid-years of the century. Notwithstanding that it has grown from historical record-keeping to a functional position indispensable in the conduct of business, today1s era of accelerated technological achievement and industrial expansion places continued challenging demands for accounting research leading to still more valuable contributions. An examination of accounting association, publications provides ample evidence of professional interest in such research. From the matrix of accounting self appraisal, dissatisfaction, investigation and trial, there have been many business oriented concepts or techniques generated which have found their way into acceptable accounting procedure. One that is in such transition today is direct costing. In past years accounting techniques have become increasingly complex, obscuring simple cost, volume, and profit relationships. Meanwhile, the tremendous technological strides in industry have resulted in the placement of many engineers, scientists, and other non-financially trained persons in top management positions. As a result of these trends, many of today 1s executives do not fully understand accounting methods and the resultant information which comprise some of their tools for decision-making. The need exists for accounting systems which are simple and show fundamental relationships readily. Direct costing fulfills these requirements.
404

Studies on the organic acid metabolism of plants in relation to the flooding tolerance of their roots

Tyler, Peter David January 1969 (has links)
1.The organic acid metabolism of the roots of wet-land species (helophytes) and that of dry-land species (non-helophytes) has been examined in relation to their tolerance to periods of experimental flooding. Growth differences between helophytes and non-helophytes were apparent only after an 18-day flood period, yet within four days of flooding differences could be observed in the levels of certain organic acids. Flooding in helophytes increased the level of root malic acid, and decreased that of succinic and lactic acid, whereas the reverse was found in non-helophytes. 2. There was evidence that under natural flooded conditions the root tissues of some wet-land species contain larger amounts of malic acid than when the flood water has receded and ground aeration improves. Shikimic acid has been detected in aquatic macrophytes and the fluctuating levels of shikimate in Iris pseudacorus and Nuphar lutea are discussed. 3. The organic acid changes related to flood tolerance operate only under partial anoxia, and under the strictly anaerobic conditions imposed by incubation of root tissue under nitrogen, there was a general reduction in all acid levels except lactate. It is suggested that non-helophytes cannot tolerate flooding through an inability to continue TCA cycle respiration during periods of reduced oxygen supply, and through the poisoning effects of ethanol accumulation. Helophyte species appear to be metabolically adapted to overcome periods of flood-induced anoxia, and tissue respiration continues with the provision for malic acid accumulation and no build-up of ethanol. 5. A tolerance of flooding, involving adaptations of the organic acid metabolism of the roots, has been demonstrated in helophyte species. This metabolic adaptation is rapidly induced, thus offering immediate protection upon flooding anoxia, and its importance in determining the ecological amplitude of a species and its possible role in future production of flood tolerant strains, are discussed.
405

The enzymic control of flooding tolerance in higher plants

McManmon, Martin January 1969 (has links)
No description available.
406

The radiative heating of plane-parallel and spherical atmosphere

Morgan, David H. January 1973 (has links)
No description available.
407

Avaliação da absorção colostral em neonatos ovinos da raça Bergamácia /

Ulian, Carla Maria Vela. January 2011 (has links)
Orientador: Simone Biagio Chiacchio / Banca: Simone Fernandes / Banca: Paulo Roberto Rodrigues Ramos / Resumo: O trabalho teve por objetivo determinar o período de absorção das macromoléculas colostrais em cordeiros da raça Bergamácia para avaliar a transferência de imunidade passiva. Foram feitas determinações eletroforéticas do soro sanguíneo antes da primeira mamada até 48 horas de vida em gel de poliacrilamida Nativa 7%, e das frações colostrais entre zero e 12 horas pós-parto por eletroforese SDS-PAGE 10%. Também a determinação da PT sérica, por refratometria, e sua relação com densidade e quantidade de gamaglobulinas no colostro da mãe. Foram utilizadas 25 ovelhas e 29 cordeiros oriundos das gestações destas fêmeas. Os momentos experimentais foram M0, M6, M12, M24, M36 e M48 para colheita sanguínea nos cordeiros. Nos momentos zero e 12 horas também foram realizadas as colheitas de colostro das fêmeas. A concentração sérica de gamaglobulina variou de 0,111±0,07g.dL-1 antes da primeira mamada (M0) a 1,609±0,72g.dL-1 às 48 horas. A concentração no colostro variou de 3,125±1,27g.dL-1 no momento zero hora para 1,378±0,82g.dL-1 às 12 horas pós-parto. A concentração de PT sérica teve acréscimo de 4,46±0,58g.dL-1 para 5,61±0,75g.dL-1 entre as zero e 48 horas de vida tendo correlação positiva com a densidade e proteína total colostral. A absorção colostral pelo cordeiro foi ascendente até o M24 quando iniciou-se a estabilização. A quantificação da PT sérica, com uso de refratômetro, pode ser usada como método para avaliar a transferência de imunidade passiva, pois está diretamente relacionada com a absorção de gamaglobulina colostral. Foi possível estabelecer uma equação preditória para a quantidade de gamaglobulina absorvida em relação ao tempo decorrido (0,0171x3 - 0,3138x2 + 1,7598x - 1,3697, R² = 0,9945) / Abstract: The purpose was determining the absorption period of the colostral globulins in Bergamasca lambs to evaluate the passive immune transfer. Determinations were made of the electrophoretic serum before the first feeding up to 48 hours of life in polyacrylamide electrophoresis gel Native 7%, and the colostrum fractions between zero and 12 hours after birth by SDS-PAGE electrophoresis 10%. Serum protein was determinate by refractometry and correlate to density and colostral gammaglobulins of the sheep. Were used 25 sheep and 29 lambs. The blood samples was collected from lambs after birth prior to suckling (M0), and on the 6, 12, 24, 36 and 48 hours of birth. On the M0 and M12, was collected colostrum samples from sheep. The serum gammaglobulin concentrations before suckling were 0,111±0,07g.dL-1 and rise until 1,609±0,72g.dL-1 to 48 hours. In colostrum was 3,125±1,27g.dL-1 in M0 and 1,378±0,82g.dL-1 to M12. The serum protein increase of 4,46±0,58g.dL-1 to 5,61±0,75g.dL-1 between zero and 48 hours having positive correlation with the gravity and colostral protein. The absorption by the lamb raised until 24 hours when stabilizes. Serum protein quantification by the refractometry could be used as a method to evaluate immune passive transfer because was directly related with the gammaglobulin colostral absorption. The concentration could be estimated using the predictive formula 0,0171x3 - 0,3138x2 + 1,7598x - 1,3697, (R² = 0,9945) for the time expend / Mestre
408

The exergy of thermal radiation and its relevance in solar energy conversion

Wright, Sean 02 May 2018 (has links)
Driven by the importance of optimizing energy systems and technologies, the field of exergy analysis was developed to better illuminate process inefficiencies and evaluate performance. Exergy analysis provides important information and understanding that cannot be obtained from energy analysis. The field of exergy analysis is well formulated and understood except for thermal radiation (TR) heat transfer. The exergy flux, or maximum work obtainable, from TR has not been unambiguously determined. Moreover, many thermodynamic textbooks are misleading by incorrectly implying that the entropy and exergy transport with TR is calculated by using the same expressions that apply to heat conduction. Research on the exergy of TR was carried out by Petela. However, many researchers have considered Petela's analysis of the exergy of TR to be irrelevant to the conversion of TR fluxes. Petela's thermodynamic approach is considered irrelevant because, others argue, that it neglects fundamental issues that are specific to the conversion of fluxes, issues that are unusual in the context of exergy analysis. The purpose of the research in this thesis is to determine, using fundamental thermodynamic principles, the exergy flux of TR with an arbitrary spectrum and its relevance to solar radiation (SR) conversion. In this thesis it is shown that Petela's result can be used for the exergy flux of blackbody radiation (BR) and represents the upper limit to the conversion of SR approximated as BR. The thesis shows this by resolving a number of fundamental issues: (1) Inherent Irreversibility; (2) Definition of the Environment; (3) Inherent Emission; (4) Threshold Behaviour; (5) Effect of Concentrating TR. This thesis also provides a new expression, based on inherent irreversibility, for the exergy flux of TR with an arbitrary spectrum. Previous analysis by Karlsson assumes that reversible conversion of non-blackbody radiation (NBR) is theoretically possible, whereas this thesis presents evidence that NBR conversion is inherently irreversible. In addition the following conclusions and contributions are made in the thesis: (1) Re-stated the general entropy and exergy balance equations for thermodynamic systems so that they correctly apply to TR heat transfer. (2) Provided second-law efficiencies for common solar energy conversion processes such as single-cell Photovoltaics. (3) Showed that Omnicolor (infinite cell) conversion, the widely held ideal conversion process for SR, is not ideal by explaining its non-ideal behaviour in terms of exergy destruction and exergy losses. (4) Presented an ideal (reversible) infinite stage thermal conversion process for BR fluxes and presented two-stage thermal conversion as a practical alternative. (5) Showed that Prigogine's minimum entropy production principle cannot be used as a governing principle in atmospheric modeling, and that in general, it may have little significance. (6) Presented a graybody model of the planet that may prove useful in understanding the thermodynamics of the Earth system. (7) Showed that the expression derived from the Clausius equality for reversible processes is applicable, whereas the statement for irreversible processes is not applicable, when there is significant heat transfer by TR. (8) Showed that the 4/3 coefficient in the BR entropy expression can be obtained by simply using the concept of equilibrium and the experimentally observable relationship for BR energy (energy x T⁴). / Graduate
409

Some studies of radiative transfer in the atmosphere : a calculation of the net radiation balance in the tropical stratosphere

Edwards, D. P. January 1970 (has links)
No description available.
410

Some spectra of single crystals

Thomson, Andrew James January 1965 (has links)
No description available.

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