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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.
11

Biodisponibilização do fósforo, incremento de energia e digestibilidade de nutrientes na dieta de frangos de corte contendo exoenzima fitase / Phosphorus bioavailability, increase of energy and digestibility of nutrients of broiler diet containing phytase exoenzima

Litz, Fernanda Heloisa 11 October 2013 (has links)
This study aimed to evaluate the effect of the use of phytase exoenzyme and other mineral sources on the bioavailability of phosphorus , increased dietary energy and nutrient digestibility . The treatments were : sorghum with inorganic phosphate ( SFB ) , maize with inorganic phosphate ( MFB ) , sorghum meal, meat and bone meal ( SFco ) , sorghum with phytase ( SFV ) and without energy recovery and amino acids ( SFNV ) . 1400 birds were for performance reviews , which were determined feed intake , body weight , feed conversion real and traditional and viability . For the analysis of digestibility at 15 days were used 80 birds , which were subjected to total collection , now for carcass composition and mineralization of tibia were used 6 birds per treatment , where we proceeded to determine the dry matter , crude protein , ether extract , ash , gross energy housing , and calcium and phosphorus of tibia and carcass. Data were subjected to analysis of variance and means were compared by Tukey test at 5 % and viability Kruskal-Wallis test . There were no statistical differences in performance at 7 days of age and only 14 live weight was lower for the MFB , however at 42 days , body weight was greater for the SFB compared to the MFB . Digestibility at 15 days there was no statistical difference. For carcass composition, the SFV showed higher percentage of ether extract. The percentage of calcium MFB FCS and were lower compared with the SFNV and equal to SFco and SFV , and the phosphorus content of the SFV and SFNV showed higher values. The exogenous phytase enzyme is able to hydrolyze phytate and release phosphorus from vegetable source for assimilation by animals , thus acting as a substitute for vegetable sources of phosphorus. / Objetivou-se avaliar o efeito da utilização da exoenzima fitase e de outras fontes minerais sobre a biodisponibilização do fósforo, o incremento de energia da ração e a digestibilidade de nutrientes. Os tratamentos foram: Sorgo com fosfato bicálcico (SFB), milho com fosfato bicálcico (MFB), sorgo com farinha de carne e ossos (SFCO), sorgo com fitase com (SFV) e sem valorização de energia e aminoácidos (SFNV). Foram 1400 aves para as análises de desempenho determinou-se o consumo de ração, peso vivo, conversão alimentar real e tradicional e a viabilidade. Para as análises de digestibilidade aos 15 dias foram utilizadas 80 aves, que foram submetidas a coleta total de excretas, já para a composição de carcaça e mineralização das tíbias foram utilizadas 6 aves por tratamento, onde procedeu-se a determinação dos teores de matéria seca, proteína bruta, extrato etéreo, matéria mineral, energia bruta da carcaça, e cálcio e fósforo das tíbias e carcaça. Os dados foram submetidos a análise de variância e as médias comparadas pelo teste de Tukey 5% e a viabilidade pelo teste Kruskal-Wallis. Não houve diferenças estatísticas para o desempenho aos 7 dias de idade e aos 14 somente o peso vivo foi menor para o MFB, já aos 42 dias, o peso vivo foi maior para o SFB comparado com o MFB. A digestibilidade aos 15 dias não houve diferença estatística. Para a composição da carcaça, o SFV apresentou maior valor da porcentagem de extrato etéreo. A porcentagem de cálcio do SFB e MFB foram menores comparado com o SFNV e iguais para SFCO e SFV, e para o teor de fósforo, o SFV e SFNV apresentaram maiores valores. A enzima fitase exógena é capaz de hidrolisar o fitato de origem vegetal e liberar o fósforo para assimilação pelos animais, atuando assim como substituta de fontes vegetais de fósforo. / Mestre em Ciências Veterinárias
12

Multivariate Synergies in Pharmaceutical Roll Compaction : The quality influence of raw materials and process parameters by design of experiments

Souihi, Nabil January 2014 (has links)
Roll compaction is a continuous process commonly used in the pharmaceutical industry for dry granulation of moisture and heat sensitive powder blends. It is intended to increase bulk density and improve flowability. Roll compaction is a complex process that depends on many factors, such as feed powder properties, processing conditions and system layout. Some of the variability in the process remains unexplained. Accordingly, modeling tools are needed to understand the properties and the interrelations between raw materials, process parameters and the quality of the product. It is important to look at the whole manufacturing chain from raw materials to tablet properties. The main objective of this thesis was to investigate the impact of raw materials, process parameters and system design variations on the quality of intermediate and final roll compaction products, as well as their interrelations. In order to do so, we have conducted a series of systematic experimental studies and utilized chemometric tools, such as design of experiments, latent variable models (i.e. PCA, OPLS and O2PLS) as well as mechanistic models based on the rolling theory of granular solids developed by Johanson (1965). More specifically, we have developed a modeling approach to elucidate the influence of different brittle filler qualities of mannitol and dicalcium phosphate and their physical properties (i.e. flowability, particle size and compactability) on intermediate and final product quality. This approach allows the possibility of introducing new fillers without additional experiments, provided that they are within the previously mapped design space. Additionally, this approach is generic and could be extended beyond fillers. Furthermore, in contrast to many other materials, the results revealed that some qualities of the investigated fillers demonstrated improved compactability following roll compaction. In one study, we identified the design space for a roll compaction process using a risk-based approach. The influence of process parameters (i.e. roll force, roll speed, roll gap and milling screen size) on different ribbon, granule and tablet properties was evaluated. In another study, we demonstrated the significant added value of the combination of near-infrared chemical imaging, texture analysis and multivariate methods in the quality assessment of the intermediate and final roll compaction products. Finally, we have also studied the roll compaction of an intermediate drug load formulation at different scales and using roll compactors with different feed screw mechanisms (i.e. horizontal and vertical). The horizontal feed screw roll compactor was also equipped with an instrumented roll technology allowing the measurement of normal stress on ribbon. Ribbon porosity was primarily found to be a function of normal stress, exhibiting a quadratic relationship. A similar quadratic relationship was also observed between roll force and ribbon porosity of the vertically fed roll compactor. A combination of design of experiments, latent variable and mechanistic models led to a better understanding of the critical process parameters and showed that scale up/transfer between equipment is feasible.

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