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Cross-flow filtration and re-suspension of fungal cellsAbdul-Salam, F. R. January 1984 (has links)
No description available.
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Cosmogenic nuclides as a surface exposure dating tool: improved altitude/latitude scaling factors for production ratesDesilets, Darin Maurice January 2005 (has links)
Applications of in situ cosmogenic nuclides to problems in Quaternary geology require increasingly accurate and precise knowledge of nuclide production rates. Production rates depend on the terrestrial cosmic-ray intensity, which is a function of the elevation and geomagnetic coordinates of a sample site and the geomagnetic field intensity. The main goal of this dissertation is to improve the accuracy of cosmogenic dating by providing better constraints on the spatial variability of production rates.In this dissertation I develop a new scaling model that incorporates the best available cosmic-ray data into a framework that better describes the effects of elevation and geomagnetic shielding on production rates. This model is based on extensive measurements of energetic nucleon fluxes from neutron monitor surveys and on more limited data from low-energy neutron surveys. A major finding of this work is that neutron monitors yield scaling factors different from unshielded proportional counters. To verify that the difference is real I conducted an airborne survey of low-energy neutron fluxes at Hawaii (19.7° N 155.5° W) to compare with a nearby benchmark neutron monitor survey. Our data confirm that the attenuation length is energy dependent and suggest that the scaling factor for energetic nucleons is 10% higher between sea level and 4000 m than for low-energy neutrons at this location. An altitude profile of cosmogenic 36Cl production from lava flows on Mauna Kea, Hawaii, support the use of neutron flux measurements to scale production rates but these data do not have enough precision to confirm or reject the hypothesis of energy-dependent scaling factors.
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Drift of Oligophlebodes sigma and Baetis bicaudatus in a Mountain StreamPearson, William Dean 01 May 1970 (has links)
The objective of this study was to clarify the relationships between drift rates, population density, production rates, key environmental factors, and movements of adults within two populations of stream insects (a caddisfly--Oligophlebodes sigma and a mayfly--Baetis bicaudatus).
Samples of benthic invertebrates (424 total) were collected every 2 8 days at four stations on Temple Fork of the Logan River, Utah, from October, 1967 to September, 1969. Samples of drift invertebrates (181 total) were collected every 14 days at three stations on Temple Fork during the same period. During summer months (June-September) a day and a night drift sample (681 total) were collected every other day.
Drift rates of O. sigma larvae were greatest (5,987 gm/year for O. sigma) when density in the benthos (256 mg/0.1 m2) and production (430 mg/0.1 m2 /year) were greatest. Drift rates were not related positively to density in the benthos over an entire year, but drift rates were correlated positively and significantly (r = .78 and .55 for day drift of O. sigma and B. biaaudatus, respectively) with density during the months of June-September for both O. sigma larvae and B. bicaudatus nymphs. Flow, distance below the spring source of Temple Fork, and densities of competing aquatic insects were other factors of significance in the multiple regression analyses of factors affecting drift rates of the two insects. The 17 independent variables in the multiple regression analyses accounted for 65 percent and 55 percent of the variability in day drift rates of o. sigma and B. bicaudatus, respectively.
The adults of O. sigma (but not those of B. bicaudatus) undertook a definite upstream migration estimated at 2-3 km. This flight of adults resulted in a concentration of eggs being laid in the upper reaches of the stream. The advantage of the upstream flight may be that it stores reproductive products in areas where they are relatively safe from the effects of anchor-ice in the winter and floods in late winter and early spring.
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Study Of Neutrino Interactions In The Chorus ExperimentCuha, Volkan 01 November 2006 (has links) (PDF)
The emulsion target of the CHORUS detector was exposed to the
wide-band neutrino beam of the CERN SPS between the years 1994 and 1997. In total about 130.000 neutrino interactions were located in the nuclear emulsion target and fully reconstructed. Detailed DATA and Monte Carlo (MC) comparisons were done in order to test reliability of the detector simulation. There is reasonable agreement between DATA and MC. The ratio of deep inelastic neutral-current (NC) to the deep inelastic (DIS) charged-current(CC) $nu_{mu}$ interactions was measured to be frac{NC_{dis}}{CC_{dis}}=0.350pm0.003$. This measurement was compared with the previous measurements. Based on three double charm decays found in NC interactions we measured the ratio of double charm cross-section in NC $nu_{mu}$ interactions to be [ frac{sigma
(cbar{c}nu_mu)}{sigma_{NC}}=(3.37^{+3.06}_{-2.51}(stat.)pm
0.51(syst.))times 10^{-3}. ] One double charm decay has been observed in CC $nu_{mu}$ interactions the upper limit on associated charm production in $nu_{mu}$ CC interaction has been found to be [ frac{sigma cbar{c}mu^{-})}{sigma_{CC}}< / 9.69 times 10^{-4}. ] at 90% C.L.
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Řizení průběhu zakázky organizací / Manufacuring Order Management in CompanyHromková, Ivana January 2011 (has links)
The diploma thesis focuses on the manufacturing order management in company. It contains examples of production systems and their analysis for optimization. During the optimization are monitored major criteria, for example: increase of production rate, resource utilization, and so on. The result of this work is a proposed solutionarising from the outputs of optimization the manufacturing system.
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UTILIZAÇÃO DE VITAMINA E, SELÊNIO E CANTAXANTINA NA PRODUÇÃO E QUALIDADE DE OVOS DE POEDEIRAS COMERCIAIS / EFFECT VITAMIN E, SELENIUM AND CANTHAXANTHIN IN THE PRODUCTION AND QUALITY EGG OF LAYING HENSFernandes, Mariane de Oliveira 22 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The experiment was conducted in an experimental avian located at the Polytechnic School of the Federal University of Santa Maria. The aim of this study was to evaluate the antioxidant effect of vitamin E, Canthaxanthin and Organic Selenium on the quality of stored eggs (0, 7, 14, 21 and 28 days) and production rates of commercial layers from 40 to 55 week of age. In total, 320 hens females of lineage Novogen Brown were distributed in a completely randomized design with 5 treatments with 8 replicates of 8 hens each. The treatments were: T1 (DNC) - Diet Negative control; T2 (DCTX) - Diet with added 6ppm of Canthaxanthin; T3 (DVitE) - diet with 200 ppm of Vitamin E; T4 (DSe) - Diet with 0,4ppm Selenium; T5 (DCTXVitESe) - Diet with added 6ppm of Canthaxanthin + 200ppm of vitamin E + 0,4ppm of Selenium . The experimental phase was divided into four periods of 28 days. The laying rate was significantly affected in hens fed with DSe in the 3rd and 4th period. Hens from DSe and DCTXVitESe had higher egg weight in the 1st period and hens fed with DCTX had better egg weight in the 4th period. The DSe provided a better feed conversion per dozen eggs in the 4th period. The feed conversion by egg mass was better for hens fed DCTX, DSe and DCTXVitESe in the 4th period. Hens fed DCTX and DCTXVitESe had higher egg weight when stored for 28 days in the 1st period. Hens from DCTX had a better percentage yolk in eggs stored for 28 days in the 3rd period and, the 4th period for eggs without storage and in eggs with 14 days of storage. In the 4th period the hens fed with DVitE had a better percentage of yolk and albumen for eggs without storage and in the eggs with 21 days of storage. The albumen percentage was better in eggs with 28 days of storage and without storage from hens fed with DCTX in the 4th period. Hens fed DSe had a better yolk index in eggs stored for 28 days in the 1st period. Eggs of hens had a better yolk color with diets DCTX and DCTXVitESe in all periods. The use of the DSe was better for the variable Unit Haugh of eggs stored for 7 days in the 1st period. The lower content of substances which react with thiobarbituric acid (TBARS) was on egg yolks of the hens fed with DVitE in the 21 days of storage. There were no differences for the variables: feed consumption, body weight, vitelline membrane strength, percentage and thickness of shell, pH of albumen and specific gravity (P>0.05). The use of different additives contributes to improve of production rates and quality of eggs. / O experimento foi conduzido em um aviário experimental localizado no Colégio Politécnico da Universidade Federal de Santa Maria. O objetivo desse estudo foi avaliar o efeito antioxidante da Vitamina E, Cantaxantina e Selênio Orgânico sobre a qualidade de ovos armazenados (0, 7, 14, 21 e 28 dias) e índices produtivos de poedeiras comerciais da 40ª a 55ª semana de idade das aves. Foram utilizadas 320 fêmeas poedeiras da linhagem Novogen Brown distribuídas em um delineamento inteiramente casualizado em 5 tratamentos com 8 repetições de 8 aves cada. Os tratamentos consistiram em: DCN - Dieta Controle negativo; DCTX - Dieta com adição de 6ppm de Cantaxantina; DVitE - Dieta com 200ppm de Vitamina E; DSe - Dieta com 0,4ppm de Selênio; DCTXVitESe - Dieta com adição de 6ppm de Cantaxantina + 200ppm de Vitamina E + 0,4ppm de Selênio. A fase experimental foi dividida em 4 períodos de 28 dias. A taxa de postura foi afetada significativamente em aves que receberam a DSe no 3º e 4º período. As aves que receberam DSe e DCTXVitESe apresentaram maior peso de ovos no 1º período, no 4º período a DCTX obteve melhor peso de ovo. A DSe proporcionou uma melhor conversão alimentar por dúzias de ovos no 4º período. A conversão alimentar por massa de ovos foi melhor para aves alimentadas com DCTX, DSe e DCTXVitESe no 4º período. As aves alimentadas com DCTX e DCTXVitESe apresentaram maior peso de ovos quando armazenados por 28 dias no 1º período. As aves que receberam DCTX apresentaram um melhor percentual de gema em ovos armazenados durante 28 dias no 3º período, no 4º período para ovos sem armazenamento e em ovos com 14 dias de estocagem. No 4º período as aves alimentadas com DVitE apresentaram um melhor percentual de gema e de albúmen para ovos sem armazenamento e com 21 dias de estocagem. O percentual de albúmen foi melhor em ovos de aves alimentadas com DCTX no 4º período com 28 dias de armazenamento e sem armazenamento. Aves alimentadas com DSe apresentaram um melhor índice de gema em ovos armazenados por 28 dias no 1º período. Obteve-se uma melhor coloração de gema através da DCTX e DCTXVitESe em todos os períodos. A utilização da DSe foi melhor para a variável unidade Haugh em ovos armazenados por 7 dias no 1º período. O teor mais baixo de substâncias que reagem com o Ácido Tiobarbitúrico (TBARS), foi em gemas de ovos de poedeiras alimentadas com DVitE com 21 dias de armazenamento. Não foram encontradas diferenças estatísticas para as variáveis de consumo de ração, peso corporal, resistência da membrana vitelina, percentual e espessura de casca, pH de albúmen e densidade específica (P>0,05). A utilização dos diferentes aditivos contribui para a melhora dos índices produtivos e de qualidade de ovos.
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Production atmosphérique du nucléide cosmogénique 10 Be et variations de l'intensité du champ magnétique terrestre au cours des derniers 800 000 ans / Atmospheric production of the cosmogenic nuclide Beryllium-10 (10Be) and geomagnetic field intensity variations over the last 800,000 yearsMénabréaz, Lucie 07 September 2012 (has links)
Parmi les méthodes de reconstitution de l'histoire du champ géomagnétique, l'étude des variations de la production atmosphérique d'isotopes cosmogéniques s'est récemment développé. Cette production est modulée au premier ordre et aux échelles multimillénaires par l'intensité du champ géomagnétique. Son enregistrement dans les archives de l'environnement terrestre en apporte une lecture indépendante, donc complémentaire des méthodes paléomagnétiques. Ce travail vise à retracer les changements de taux de production de 10Be enregistrés dans les sédiments marins, afin de restituer les variations du moment géomagnétique depuis environ 800 000 ans. Les rapports 10Be/9Be authigéniques mesurés par Spectrométrie de Masse par Accélérateur le long de trois séquences de différentes latitudes, permettent de caractériser la production globale de 10Be sur deux intervalles de temps. (1) Lors de la baisse du moment dipolaire associée à l'excursion Laschamp (~41 000 ans BP), la surproduction de 10Be à 38°N et 2°S, confirmée par des mesures de 10Be/230Thxs, est identique à celle restituée dans les glaces du Groenland. (2) L'étude menée sur une carotte prélevée à l'équateur couvrant l'intervalle 800 000 – 250 000 ans BP (époque Brunhes), révèle les phases successives de surproduction globale de 10Be déclenchées par les chutes de moment dipolaires liées à l'inversion Brunhes-Matuyama d'une part et d'autre part à une dizaine d'excursions documentées. La calibration de ces enregistrements avec des valeurs absolues disponibles dans la littérature permet la quantification des moments dipolaires. / Among the methods for reconstructing the geomagnetic field history, studying the variations in cosmogenic isotopes production in the atmosphere has recently developed. At multi millennial scales, this production is mainly modulated by the geomagnetic field intensity. Its record in terrestrial archives provides an independent reading to complement paleomagnetic methods. This work aims at tracing the changes in 10Be production rates recorded in marine sediments, in order to reproduce the geomagnetic variations for the past 800,000 years. Authigenic 10Be/9Be ratios measured using Accelerator Mass Spectrometry along three sequences from different latitudes, characterize the 10Be global production during two time intervals. (1) During the dipole moment low associated with the Laschamp excursion (~ 41,000 years BP), the 10Be overproduction at 38°N and 2°S, confirmed by measurements of 10Be/230Thxs, is identical to that recorded in the Greenland ice sheet. (2) Studying a core collected near the equator and covering the interval 800,000 – 250,000 years BP (Brunhes epoch) reveals the successive phases of global 10Be overproductions triggered by dipole moment lows associated to the Brunhes-Matuyama reversal and also to several other documented excursions. Calibrating these records with absolute values available in the literature allows quantifying dipole moments. These are then compared to paleomagnetic reference reconstructions over the same time series. Bearing out the number and extent of these dipole field lows allows considering to refine their chronology before using their features to get a better understanding of the geodynamo rhythms throughout the last Million years.
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Pressure Normalization of Production Rates Improves Forecasting ResultsLacayo Ortiz, Juan Manuel 16 December 2013 (has links)
New decline curve models have been developed to overcome the boundary-dominated flow assumption of the basic Arps’ models, which restricts their application in ultra-low permeability reservoirs exhibiting long-duration transient flow regimes. However, these new decline curve analysis (DCA) methods are still based only on production rate data, relying on the assumption of stable flowing pressure. Since this stabilized state is not reached rapidly in most cases, the applicability of these methods and the reliability of their solutions may be compromised. In addition, production performance predictions cannot be disassociated from the existing operation constraints under which production history was developed. On the other hand, DCA is often carried out without a proper identification of flow regimes. The arbitrary application of DCA models regardless of existing flow regimes may produce unrealistic production forecasts, because these models have been designed assuming specific flow regimes.
The main purpose of this study was to evaluate the possible benefits provided by including flowing pressures in production decline analysis. As a result, it have been demonstrated that decline curve analysis based on pressure-normalized rates can be used as a reliable production forecasting technique suited to interpret unconventional wells in specific situations such as unstable operating conditions, limited availability of production data (short production history) and high-pressure, rate-restricted wells. In addition, pressure-normalized DCA techniques proved to have the special ability of dissociating the estimation of future production performance from the existing operation constraints under which production history was developed. On the other hand, it was also observed than more consistent and representative flow regime interpretations may be obtained as diagnostic plots are improved by including MBT, pseudovariables (for gas wells) and pressure-normalized rates. This means that misinterpretations may occur if diagnostic plots are not applied correctly.
In general, an improved forecasting ability implies greater accuracy in the production performance forecasts and more reliable reserve estimations. The petroleum industry may become more confident in reserves estimates, which are the basis for the design of development plans, investment decisions, and valuation of companies’ assets.
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