949 resultados para Starch Grains


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The aim of this study was to determine the potential of biochemical parameters, such as enzyme activity and adenosine triphosphate (ATP) levels, as monitors of process performance in the Upflow Anaerobic Sludge Blanket (UASB) reactor utilizing a starch wastewater. The acid and alkaline phosphatase activity and the ATP content of the UASB sludge were measured in response to changes in flow rate and nutrient loading. Conventional parameters of process performance, such as gas production, acetic acid production, COD, phosphorus, nitrogen and suspended solids loadings and % COD removal were also monitored. The response of both biochemical and conventional parameters to changing process conditions was then compared. Alkaline phosphatase activity exhibited the highest activity over the entire study perioda A high suspended solids loading was observed to upset the system in terms of gas production, acetic acid production and % COD removala The initial rate of increase in alkaline phosphatase activity following an increase in loading was four times as great during process upset than under conditions of good performance. The change in enzyme actiVity was also more sensitive to process upset than changes in acetic acid production. The change in ATP content of the sludge with time suggested that enzyme actiVity was changing independently of the actual viable biomass present. The bacterial composition of the anaerobic sludge granules was similar to that of other sludge bed systems, at the light and scanning electron microscope level. Isolated serum bottle cultures produced several acids involved in anaerobic carbohydrate metabolism. The overall performance of the UASB system indicated that higher loadings of soluble nutrients could have been tolerated by the system.

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Micromorphology is used to analyze a wide range of sediments. Many microstructures have, as yet, not been analyzed. Rotation structures are the least understood of microstructures: their origin and development forms the basis of this thesis. Direction of rotational movement helps understand formative deformational and depositional processes. Twenty-eight rotation structures were analyzed through two methods of data extraction: (a) angle of grain rotation measured from Nikon NIS software, and (b) visual analyses of grain orientation, neighbouring grainstacks, lineations, and obstructions. Data indicates antithetic rotation is promoted by lubrication, accounting for 79% of counter-clockwise rotation structures while 21 % had clockwise rotation. Rotation structures are formed due to velocity gradients in sediment. Subglacial sediments are sheared due to overlying ice mass stresses. The grains in the sediment are differentially deformed. Research suggests rotation structures are formed under ductile conditions under low shear, low water content, and grain numbers inducing grain-to-grain interaction.

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High chromium content in kimberlite indicator minerals such as pyrope garnet and diopside is often correlated with the presence of diamonds. In this study, kimberlite indicator minerals were examined using visible light reflectance spectroscopy to determine if chromium content can be correlated with spectral absorption features. The depth of absorption features in the visible spectral region were correlated with the molecular percentage of chromium and other first series transition metal elements obtained by electron microprobe data. In the visible part of the spectrum, chromium is evident by 3 absorption features in the pyrope reflectance spectrum; one isolated and narrow feature at the wavelength 689 nm was used to correlate with the chromium mol %. The isolation of this feature in the pyrope spectra is advantageous since it is not directly affected by other proximal absorption bands that could be caused by other transition metals. Analysis of the feature indicates that as grain volume increases the depth of the absorption feature will also increase. Clustering grain volumes into fractions yields better correlation between absorption depth and mol % chromium. Other types of garnet (almandine, grossular, spessartine) and kimberlite indicator minerals (olivine, diopside, chromite, ilmenite) were analyzed to determine if other absorption features could be used to predict the proportion of specific transition metal elements. Diopside in particular illustrates the same isolated chromium absorption feature as pyrope and may indicate mol percent but needs further study with larger sample sets.

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CASCO (Canada Starch Company) began operations in 1982 and was officially opened in May of 1983. Premier William Davis was in attendance. CASCO is a company whose roots can be traced back to 1858 when it was founded by W.T. Benson in Cardinal, Ontario. The company grew as corn uses were developed. Corn derived products now include: corn oil, liquid sweetener and feed for dairy and cattle. Starch is used as a finish for fine papers, a component in dry cell batteries, pharmaceuticals, wallpaper, film, tires, surgical dressings, plastics and plywood. Corn syrup is used in beverages, canned fruit, frozen seafood, licorice, ice cream and baking products. Corn solubles are used in animal feed, rubber substitutes, soap, paint and varnish. There are more than 250 industrial and food uses for corn

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Les amidons non modifiées et modifiés représentent un groupe d’excipients biodégradables et abondants particulièrement intéressant. Ils ont été largement utilisés en tant qu’excipients à des fins diverses dans des formulations de comprimés, tels que liants et/ou agents de délitement. Le carboxyméthylamidon sodique à haute teneur en amylose atomisé (SD HASCA) a été récemment proposé comme un excipient hydrophile à libération prolongée innovant dans les formes posologiques orales solides. Le carboxyméthylamidon sodique à haute teneur en amylose amorphe (HASCA) a d'abord été produit par l'éthérification de l'amidon de maïs à haute teneur en amylose avec le chloroacétate. HASCA a été par la suite séché par atomisation pour obtenir le SD HASCA. Ce nouvel excipient a montré des propriétés présentant certains avantages dans la production de formes galéniques à libération prolongée. Les comprimés matriciels produits à partir de SD HASCA sont peu coûteux, simples à formuler et faciles à produire par compression directe. Le principal objectif de cette recherche était de poursuivre le développement et l'optimisation des comprimés matriciels utilisant SD HASCA comme excipient pour des formulations orales à libération prolongée. A cet effet, des tests de dissolution simulant les conditions physiologiques du tractus gastro-intestinal les plus pertinentes, en tenant compte de la nature du polymère à l’étude, ont été utilisés pour évaluer les caractéristiques à libération prolongée et démontrer la performance des formulations SD HASCA. Une étude clinique exploratoire a également été réalisée pour évaluer les propriétés de libération prolongée de cette nouvelle forme galénique dans le tractus gastro-intestinal. Le premier article présenté dans cette thèse a évalué les propriétés de libération prolongée et l'intégrité physique de formulations contenant un mélange comprimé de principe actif, de chlorure de sodium et de SD HASCA, dans des milieux de dissolution biologiquement pertinentes. L'influence de différentes valeurs de pH acide et de temps de séjour dans le milieu acide a été étudiée. Le profil de libération prolongée du principe actif à partir d'une formulation de SD HASCA optimisée n'a pas été significativement affecté ni par la valeur de pH acide ni par le temps de séjour dans le milieu acide. Ces résultats suggèrent une influence limitée de la variabilité intra et interindividuelle du pH gastrique sur la cinétique de libération à partir de matrices de SD HASCA. De plus, la formulation optimisée a gardé son intégrité pendant toute la durée des tests de dissolution. L’étude in vivo exploratoire a démontré une absorption prolongée du principe actif après administration orale des comprimés matriciels de SD HASCA et a montré que les comprimés ne se sont pas désintégrés en passant par l'estomac et qu’ils ont résisté à l’hydrolyse par les α-amylases dans l'intestin. Le deuxième article présente le développement de comprimés SD HASCA pour une administration orale une fois par jour et deux fois par jour contenant du chlorhydrate de tramadol (100 mg et 200 mg). Ces formulations à libération prolongée ont présenté des valeurs de dureté élevées sans nécessiter l'ajout de liants, ce qui facilite la production et la manipulation des comprimés au niveau industriel. La force de compression appliquée pour produire les comprimés n'a pas d'incidence significative sur les profils de libération du principe actif. Le temps de libération totale à partir de comprimés SD HASCA a augmenté de manière significative avec le poids du comprimé et peut, de ce fait, être utilisé pour moduler le temps de libération à partir de ces formulations. Lorsque les comprimés ont été exposés à un gradient de pH et à un milieu à 40% d'éthanol, un gel très rigide s’est formé progressivement sur leur surface amenant à la libération prolongée du principe actif. Ces propriétés ont indiqué que SD HASCA est un excipient robuste pour la production de formes galéniques orales à libération prolongée, pouvant réduire la probabilité d’une libération massive de principe actif et, en conséquence, des effets secondaires, même dans le cas de co-administration avec une forte dose d'alcool. Le troisième article a étudié l'effet de α-amylase sur la libération de principe actif à partir de comprimés SD HASCA contenant de l’acétaminophène et du chlorhydrate de tramadol qui ont été développés dans les premières étapes de cette recherche (Acetaminophen SR et Tramadol SR). La modélisation mathématique a montré qu'une augmentation de la concentration d’α-amylase a entraîné une augmentation de l'érosion de polymère par rapport à la diffusion de principe actif comme étant le principal mécanisme contrôlant la libération de principe actif, pour les deux formulations et les deux temps de résidence en milieu acide. Cependant, même si le mécanisme de libération peut être affecté, des concentrations d’α-amylase allant de 0 UI/L à 20000 UI/L n'ont pas eu d'incidence significative sur les profils de libération prolongée à partir de comprimés SD HASCA, indépendamment de la durée de séjour en milieu acide, le principe actif utilisé, la teneur en polymère et la différente composition de chaque formulation. Le travail présenté dans cette thèse démontre clairement l'utilité de SD HASCA en tant qu'un excipient à libération prolongée efficace.

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L’objectif de cette étude a été d’évaluer l’effet du remplacement total ou partiel du maïs d’une ration alimentaire standard (MS) sur les performances de croissance, le pH ruminal et les paramètres biochimiques sanguins chez les veaux de grain de race Holstein. Quatre groupes de 80 veaux ont été répartisen32 parcs (10 veaux/parc) et ont été assignés au hasard à quatre rations alimentaires. Les rations alimentaires ont été: la ration standard qui est constituée de maïs et un supplément protéique à 43,6% de protéine brute (MS);une ration réduite de maïs, avec tourteau de canola et de drèche de distillerie de maïs avec soluble (MCD); une ration réduite de maïs, avec supplément protéique à 43,6% de protéine brute et de drèche de distillerie de maïs avec soluble (MSD); et finalement une ration d’orge roulé, de tourteau de canola et de drèche de distillerie de maïs avec soluble (OCD). Les rations alimentaires ont été formulées selon une phase de démarrage P1 (j0 à j54), une de croissance P2 (j55 à j85) et une de finition P3 (j86 à j96). Un groupe additionnel de 5 veaux contrôle (CT), a reçu une ration alimentaire non acidogène à base de fourrage et de concentré. Notons qu’avant le début des traitements alimentaires au j0, sauf CT, les veaux ont reçu une ration d’adaptation contenant du maïs et de l’orge (50-50) et un supplément protéique pendant 20j. Les gains moyens quotidiens (GMQ) ont été similaires aux périodes P1 (0j-j27, j28-j54) et P2 (j55-j85), mais à la période P3 (j86-j96), le GMQ de la ration OCD a été plus grand que ceux dans les autres rations (p<0.001). Le rendement carcasse des veaux abattus au poids vifs d’environ 267 kg, de la ration OCD a été plus petit que ceux des rations MS et MSD (p<0.002). La matière sèche ingérée (MSI) a diminué pour le groupe MSD au j96, comparée à celles des groupes MS et BCD (p<0.001). Cependant, les rations alimentaires n’ont pas eu d’effet sur le poids vif des veaux. Les durées moyennes en dessous du pH ruminal de 5.6 (DpH5.6 en h.j.-1) du j68 au j85 (P2) ont été similaires pour les groupes CT et OCD (p=0.09) et plus petites (p<0.001) que celles des groupes du MS, MCD et MSD. Pendant la phase P3, les DpH5.6 des groupes de MS, MCD et MSD, ont été similaires (p>0.83), mais plus grandes que celle du groupe de OCD (p<0.0001). Les DpH5.6 n’ont pas eu d’effet sur les GMQ. Aux j68 et j96, les rations alimentaires n’ont pas eu d’effet sur la L-lactate (p > 0.05), le pH sanguin (p > 0.001; non significatif après l’ajustement de Bonferroni :NSAB) et le trou anionique (p > 0.009; NSAB). La PCO2 des animaux du groupe MS a été plus grande que celle du groupe CT (p = 0.0003). Au j68, HCO3 - du groupe CT a été plus grande que celle du groupe MCD (p = 0.0008). Les traitements alimentaires n’ont pas d’effets sur la lipopolysaccharide binding protein (LBP) aux j0 et j68. Au j96, la LBP du groupe CT a été plus petite que celle du groupe MS et MCD (p=0.001). Les diètes n’ont pas d’effets significatifs sur les épithéliums et les lamina propria du rumen (p0>0.37), ainsi que sur les abcès du foie (p=0.80). Le remplacement total du maïs par l’orge roulé, la drêche de distillerie de maïs avec soluble et le tourteau de canola amélioré le GMQ en phase de finition, a amélioré le pH du rumen, le rapprochant du pH ruminal physiologique, n’a pas modifié les paramètres biochimiques sanguins qui ont été mesurés et a diminué le rendement carcasse moyen de 1,1%.

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Glucoamylase from Aspergillus Niger was immobilized on montmorillonite clay (K-10) by two procedures, adsorption and covalent binding. The immobilized enzymes were characterized using XRD, surface area measurements and 27Al MAS NMR and the activity of the immobilized enzymes for starch hydrolysis was tested in a fixed bed reactor (FBR). XRD shows that enzyme intercalates into the inter-lamellar space of the clay matrix with a layer expansion up to 2.25 nm. Covalently bound glucoamylase demonstrates a sharp decrease in surface area and pore volume that suggests binding of the enzyme at the pore entrance. NMR studies reveal the involvement of octahedral and tetrahedral Al during immobilization. The performance characteristics in FBR were evaluated. Effectiveness factor (η) for FBR is greater than unity demonstrating that activity of enzyme is more than that of the free enzyme. The Michaelis constant (Km) for covalently bound glucoamylase was lower than that for free enzyme, i.e., the affinity for substrate improves upon immobilization. This shows that diffusional effects are completely eliminated in the FBR. Both immobilized systems showed almost 100% initial activity after 96 h of continuous operation. Covalent binding demonstrated better operational stability.

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In India, Food Security meant supply of food grains and the medium was Public Distribution System. Public Distribution System (PDS) is a rationing mechanism that entitles households to specified quantities of selected commodities at subsidized prices. The Objectives of PDS are maintaining Price Stability, rationing during times of scarcity, welfare of the poor, and keeping a check on private trade. Kerala has registered remarkable improvement in poverty reduction in general over the years among all social sections, including scheduled caste and scheduled tribe population. As part of the structural adjustment intended to reduce public expenditure, PDS has been modified as Revamped PDS (RPDS) during 1992 and later on as Targeted PDS (TPDS) in 1997, intended to target households on the basis of income criterion, classifying people as Below Poverty Line (BPL) and Above Poverty Line (APL). TPDS provides 25Kg. of food gra.ins through the Fair Price Shops per month @ Rs.3/- per Kg. of rice/ wheat to the BPL category and @Rs.8.90 and Rs.6.7O for rice and wheat respectively to the APL category of people. Since TPDS is intended to target the poor people, the subsidy spent by the government for the scheme should be beneficial to the poor people and naturally they should utilize the benefits by purchasing the food grains allotted under the scheme. Several studies have shown that there is underutilization of the allotments under TPDS. Therefore, the extent of utilization of TPDS in food grains, how and why remains as a major hurdle, in improving the structure and system of PDS. Livelihood of the tribal population being under threat due to increasing degradation of the resources, the targeting system ought to be effective among the tribal population. Therefore, performance of the TPDS in food grains, in terms of the utilization by the tribal population in Kerala, impact thereof and the factors, if any, affecting proper utilization were considered as the research problem in this study. The study concentrated on the pattern of consumption of food grains by the tribal people, whether their hunger needs are met by distribution of food grains through the TPDS, extent to which TPDS in food grains reduce their share of expenditure on food in the total household expenditure, and the factors affecting the utilization of the TPDS in food grains by the tribal population. Going through the literature, it has been noted that only few studies concentrated on the utilization of TPDS in food grains among the tribal population in Kerala.The Research Design used in this study is descriptive in nature, but exploratory in some aspects. Idukki, Palakkad and Wayanad have more than 60% of the population of the tribals in the state. Within the three districts mentioned above, 14 villages with scheduled tribe concentration were selected for the study. 95 tribal colonies were selected from among the various tribal settlements. Collection of primary data was made from 1231 households with in the above tribal colonies. Analysis of data on the socio-economic factors of the tribal people, pattern of food consumption, extent of reduction in the share of expenditure on food among the household expenditure of the tribal people and the impact of TPDS on the tribal families etc. and testing of hypotheses to find out the relation/association of each of the six variables, using the data on BPL and APL categories of households separately have resulted in findings such as six percent of the tribal families do not have Ration Cards, average per capita consumption of food grains by the tribal people utilizing TPDS meets 62% of their minimum requirement, whereas the per capita consumption of food grains by the tribal people is higher than the national average per capita consumption, 63% deficiency in food grains may be felt by tribal people in general, if TPDS is withdrawn, and the deficit for BPL tribal people may be 82%, TPDS facilitates a reduction of 9.71% in the food expenditure among the total household expenditure of the tribal people in general, share of food to non-food among BPL category of tribals is 55:45 and 40:60 among the APL, Variables, viz. household income, number of members in the family and distance of FPS from tribal settlements etc. have influence on the quantity of rice being purchased by the tribal people from the Fair Price Shops, and there is influence of household income and distance of FPS from tribal settlements on the quantity of rice being purchased by the tribal people from the open market. Rationing with differential pricing on phased allotments, rectification of errors in targeting, anomalies in norms and procedures for classifying tribal people as BPL/APL, exclusive Income Generation for tribal population, paddy cultivation in the landholdings possessed by the tribal people, special drive for allotment of Ration Cards to the tribal people, especially those belonging to the BPL category, Mobile Fair Price Shops in tribal settlements, ensure quality of the food grains distributed through the TPDS, distribution of wheat flour in packed condition instead of wheat through the Fair Price Shops are recommended to address the shortcomings and weaknesses of the TPDS vis-avis the tribal population in Kerala.

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Biodegradation is the chemical degradation of materials brought about by the action of naturally occurring microorganisms. Biodegradation is a relatively rapid process under suitable conditions of moisture, temperature and oxygen availability. The logic behind blending biopolymers such as starch with inert polymers like polyethylene is that if the biopolymer component is present in sufficient amount, and if it is removed by microorganisms in the waste disposal environment, then the base inert plastic should slowly degrade and disappear. The present work focuses on the preparation of biodegradable and photodegradable blends based on low density polyethylene incorporating small quantities of ionomers as compatibilizers. The thesis consists of eight chapters. The first chapter presents an introduction to the present research work and literature survey. The details of the materials used and the experimental procedures undertaken for the study are described in the second chapter. Preparation and characterization of low density polyethylene (LDPE)-biopolymer (starch/dextrin) blends are described in the third chapter. The result of investigations on the effect of polyethylene-co-methacrylic acid ionomers on the compatibility of LDPE and starch are reported in chapter 4. Chapter 5 has been divided into two parts. The first part deals with the effect of metal oxides on the photodegradation of LDPE. The second part describes the function of metal stearates on the photodegradation of LDPE. The results of the investigations on the role of various metal oxides as pro-oxidants on the degradation of ionomer compatibilized LDPE-starch blends are reported in chapter 6. Chapter 7 deals with the results of investigations on the role of various metal stearates as pro-oxidants on the degradation of ionomer compatibilized LDPE-starch blends. The conclusion of the investigations is presented in the last chapter of the thesis.

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Low-density polyethylene, (LDPE) was mixed with two grades of tapioca starch–lowgrade and high-grade. Various compositions were prepared and mechanical and thermal studies performed. The biodegradability of these samples was checked using a culture medium containing Vibrios (an amylase-producing bacteria), which was isolated from a marine benthic environment. The soil burial test and reprocessability of these samples were checked. The studies on biodegradability show that these blends are partially biodegradable. These low-density polyethylene-starch blends are reprocessable without sacrificing much of their mechanical properties

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Effect of varying spray rate on the structure and optoelectronic properties of spray pyrolysed ZnO film is analysed. ZnO films were characterised using different techniques such as X-ray diffraction (XRD), photoluminescence, electrical resistivity measurement, and optical absorption. The XRD analysis proved that, with the increase in spray rate, orientation of the grains changed from (1 0 1) plane to (0 0 2) plane. The films exhibited luminescence in two regions—one was the ‘near band-edge’ (NBE) (∼380 nm) emission and the other one was the ‘blue-green emission’ (∼503 nm). Intensity of the blue-green emission decreased after orientation of grains shifted to (0 0 2) plane. Scanning electron microscope (SEM) analysis of the films asserts that spray rate has major role in improving the crystallographic properties of the films. Moreover resistivity of the films could be lowered to 2.4×10−2 cm without any doping or post-deposition annealing