971 resultados para QUANTITATIVE CHEMICAL ANALYSIS


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The present investigation on " Hydrology, stratigraphy, and evolution of the palaeo-lagoon (Koleland basin)in the Central Kerala coast, India" is an integrated approach based on hydrogeological,geophysical,hydrochemical and stratigraphic aspects.A strong scientific data base of the study area is generated using interpretation of well observation and water quality analysis. The salient findings of the present study are given to provide a holistic picture on the hydrogeology (including groundwater resource and its quality),stratigraphy and evolution of the palaeo-lagoon

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The selective oxidation of alkylaromatics is one of the main processes since the reaction products are important as intermediates in numerous industrial organic chemicals. Side-chain oxidation of alkyl aromatic compounds catalyzed by heterogeneous catalysts using cleaner peroxide oxidants is an especially attractive goal since classical synthetic laboratory procedures preferably use permanganate or acid dichromate as stoichiometric oxidants. In spite of many studies, there are very few which use hydrogen peroxide as a source of oxygen in the C-H activation of alkanes. Eflective utilization of ethylbenzene, available in the xylene stream of the petrochemical industry to more value added products is a promising one in chemical industry. The oxidation products of ethylbenzene are widely employed as intermediates in organic, steroid and resin synthesis.

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The study was undertaken with the aim to study the variation of different components in the drip/liquid and meat sampled at different stages of processing. The fresiand the frozen oyster meat were canned in Tin and in Aluminium cans. Various media like brine, oil, tomato sauce and wine were used. Observations were made physically and chemically for the drip/liquids and the meat at different stages of processing. The chemical analysis were made for certain nutritional and mineral components

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Cerebral glioma is the most prevalent primary brain tumor, which are classified broadly into low and high grades according to the degree of malignancy. High grade gliomas are highly malignant which possess a poor prognosis, and the patients survive less than eighteen months after diagnosis. Low grade gliomas are slow growing, least malignant and has better response to therapy. To date, histological grading is used as the standard technique for diagnosis, treatment planning and survival prediction. The main objective of this thesis is to propose novel methods for automatic extraction of low and high grade glioma and other brain tissues, grade detection techniques for glioma using conventional magnetic resonance imaging (MRI) modalities and 3D modelling of glioma from segmented tumor slices in order to assess the growth rate of tumors. Two new methods are developed for extracting tumor regions, of which the second method, named as Adaptive Gray level Algebraic set Segmentation Algorithm (AGASA) can also extract white matter and grey matter from T1 FLAIR an T2 weighted images. The methods were validated with manual Ground truth images, which showed promising results. The developed methods were compared with widely used Fuzzy c-means clustering technique and the robustness of the algorithm with respect to noise is also checked for different noise levels. Image texture can provide significant information on the (ab)normality of tissue, and this thesis expands this idea to tumour texture grading and detection. Based on the thresholds of discriminant first order and gray level cooccurrence matrix based second order statistical features three feature sets were formulated and a decision system was developed for grade detection of glioma from conventional T2 weighted MRI modality.The quantitative performance analysis using ROC curve showed 99.03% accuracy for distinguishing between advanced (aggressive) and early stage (non-aggressive) malignant glioma. The developed brain texture analysis techniques can improve the physician’s ability to detect and analyse pathologies leading to a more reliable diagnosis and treatment of disease. The segmented tumors were also used for volumetric modelling of tumors which can provide an idea of the growth rate of tumor; this can be used for assessing response to therapy and patient prognosis.

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This study was undertaken to isolate ligninase-producing white-rot fungi for use in the extraction of fibre from pineapple leaf agriwaste. Fifteen fungal strains were isolated from dead tree trunks and leaf litter. Ligninolytic enzymes (lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac)), were produced by solid-state fermentation (SSF) using pineapple leaves as the substrate. Of the isolated strains, the one showing maximum production of ligninolytic enzymes was identified to be Ganoderma lucidum by 18S ribotyping. Single parameter optimization and response surface methodology of different process variables were carried out for enzyme production. Incubation period, agitation, and Tween-80 were identified to be the most significant variables through Plackett-Burman design. These variables were further optimized by Box-Behnken design. The overall maximum yield of ligninolytic enzymes was achieved by experimental analysis under these optimal conditions. Quantitative lignin analysis of pineapple leaves by Klason lignin method showed significant degradation of lignin by Ganoderma lucidum under SSF

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Four Venda indigenous scavenging (VIS) chickens (one young male and one young female of 10-16 weeks of age, a mature cockerel and a mature hen) were randomly purchased from each of six adjacent rural villages during three different seasons (autumn, winter and spring) to determine the meat yield and carcass chemical composition. A total of 72 chickens were slaughtered and feathers, head, neck, viscera, feet and lungs were removed. The live body weight, dressed carcass weight and also the mass of the breast without wings, thighs and drumsticks were recorded with bones and skin. The muscle tissues of the breast and both legs without tendons and fat were sampled for chemical analysis and were analysed for dry matter, ether extract, crude protein and ash. The carcass weight, dressing %, mass of the breast, mass of the thighs, mass of the drumsticks, breast yield, thighs yield and drumsticks yield of both grower and adult VIS chickens were not influenced by season. The crude protein of the grower chickens breast muscles and fat content of the adult chicken leg muscles differed with season. The meat from VIS chickens provided a constant nutrient (crude protein) supply throughout the year to the rural communities.

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El estudio realizado se basó en la aplicación de la metodología de investigación científica y el análisis exploratorio, cuantitativo de tipo descriptivo de corte transversal, utilizando análisis de relaciones de datos obtenidos en cada una de las IPS y relaciones de perfiles entre de la población atendida. El análisis de la información mostró que las barreras administrativas de acceso a los servicios de Gineco-Obstetricia existen en las IPS estudiadas, caracterizando fundamentalmente aspectos relacionados con la falta de registro de información en las historias clínicas de los pacientes, la falta de registro de la no asistencia de un paciente a una cita, la inexistencia de acciones registradas frente a la identificación e inscripción de la población objeto de control prenatal con clasificación del riesgo, el régimen de afiliación, la ocupación, las acciones correctivas por fallas en los servicios de salud, el registro de fallas en los servicios de salud y el nivel educativo. Es valiosa la información que es registrada en las historias clínicas, sin embargo las IPS que participaron en el presente estudio no le dan la importancia necesaria a las evidencias obtenidas, en especial frente a acciones correctivas. Las relaciones entre las variables como el número de embarazos, el número de controles prenatales, el número de abortos, las IPS, los perfiles de la población de pacientes, la falta de registro de la no asistencia de un paciente a una cita, la clasificación del riesgo, el número de partos, el estado civil, los grupos de edad, el nivel educativo, el registro de fallas, el registro de las acciones correctivas y la ocupación, permiten identificar barreras de acceso administrativas. Se realizó una entrevista a los líderes de los procesos de calidad o directores generales de las IPS que participaron en el presente estudio y se encontró que los parámetros de calidad son claros y que la información existe en diferentes proporciones y protocolos institucionales. No obstante, las IPS no aplican en su totalidad el modelo de los canones establecidos. Es necesario que las instituciones apliquen las normas de calidad en su totalidad lo que seguramente las llevará a lograr mejores resultados.

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La incidència sobre el suro de defectes sensorials amb descriptors de florit-humitat és un dels principals problemes amb què s'enfronta la indústria surera. Els principals compostos relacionats amb aquest defecte son cloroanisoles, metoxipirazines, geosmina i metilisoborneol. Aquesta recerca s'ha fet amb l'objectiu principal d'aprofundir en els mètodes de determinació de compostos volàtils en suro. S'ha desenvolupat una metodologia basada en la microextracció en fase sòlida i la cromatografia de gasos per a l'anàlisi conjunta d'aquests compostos en macerats de suro. El fet que la majoria dels compostos d'interès tingui un origen microbià ha fet necessari completar les anàlisis químiques amb mètodes de detecció i aïllament dels microorganismes susceptibles de produir-los. S'ha utilitzat un mètode per a l'estudi de la diversitat de fongs i bacteris en mostres de suro basat en l'estudi de marcadors genètics mitjançant l'anàlisi en gradients electroforètics desnaturalitzants. Per últim s'ha avaluat la capacitat de producció de defectes sensorials per microorganismes aïllats de suro utilitzant tècniques olfactomètriques.

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RESUMO: A preocupação central desta pesquisa foi compreendermos qual o impacto da formação continuada Pró-Letramento na prática pedagógica do professor a partir das necessidades e desafios do cotidiano escolar. Buscamos conhecer o conceito que os sujeitos da pesquisa têm sobre formação continuada, abordando a mesma como elemento da prática docente, comparamos o cotidiano de sala de aula de professores que passaram pela formação Pró-Letramento com os que não tiveram acesso a essa formação. Com respeito à formação continuada a percebemos como um processo dinâmico, reflexivo, que combina uma variedade de possibilidades e modalidades de aprendizagens, em que o professor vai adequando a sua formação às exigências sociais, culturais, educacionais. A formação continuada se dá, por meio da reflexão sobre a própria prática profissional no processo de ação-reflexão-ação, adquirindo significado na medida em que desenvolve e promove os diversos saberes docentes. A pesquisa foi conduzida com 90 professores do Ensino Fundamental – Anos Iniciais -, com oito coordenadoras que acompanham pedagogicamente os professores sujeitos dessa pesquisa e a observação em sala de aula. Procedeu-se à aplicação de um questionário validado e adaptado aos professores e uma entrevista aos coordenadores. A análise dos dados quantitativos foi realizada por meio do programa SPSS; enquanto a análise dos dados qualitativos foi orientada pela análise de discurso. A pesquisa aponta para algumas conclusões no que se refere a importância da Formação Continuada Pró-Letramento, tendo em vista a mesma possibilitar mudanças na prática pedagógica e colaborara para formação de um professor reflexivo, ao mesmo tempo que abre espaço para novos questionamentos e novos estudos.ABSTRACT: The central concern of this research was to understand the impact of the continuing education pro-literacy teaching practice from the teacher‘s needs and challenges of every day school life. We tried to know the concept that the subjects have on continuing education, addressing it as part of teaching practice, we compared the daily classroom teachers who have gone through training with Pro-Literacy did not access to such training. With respect to continuing education perceive it as a dynamic, reflective, which combines a variety of possibilities and modalities oF learning, the teacher will tailoring the training requirements to social, cultural, educational. The continuing education takes place, through reflection on own practice in the process of action-reflection-action, acquiring significance in that it develops and promotes the various teacher‘s knowledge. The research was conducted with 90 elementary school teacher‘s – Early Years – with eight coordinators accompanying teacher‘s pedagogically subject of research and observation in the classroom. Proceeded to the application of a validated questionnaire and adapted to an interview with the teachers and coordinators. The quantitative data analysis was performed using SPSS, while the analysis of qualitative data was guided by discourse analysis. The research points to some conclusions regarding the importance of Continuing Education Pro- Literacy in order to enable the same changes in teaching practice and collaborated to form a reflective teacher at the same time it makes room for new questions and new studies.

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Este trabalho tem como principal objetivo estudar a relação entre o comprometimento organizacional e a satisfação no trabalho em voluntários pertencentes a diferentes organizações de terceiro sector da zona da Grande Lisboa. A amostra em estudo é constituída por 121 voluntários, com idades compreendidas entre os 12 e os 63 anos, de ambos os géneros e com habilitações literárias desde o 4ª ano ao ensino superior. No que concerne à metodologia, é utilizado um questionário que mede o comprometimento organizacional, elaborado por Allen e Meyer (1997) e um inventário sobre a satisfação global com trabalho proposto por Hackman e Oldham (1975). Na análise dos dados utilizou-se o programa estatístico SPSS. Os resultados obtidos confirmam a existência de uma relação entre o comprometimento organizacional e a satisfação global com o trabalho. De entre as dimensões do comprometimento organizacional, aquela que possui um melhor poder preditivo sobre a satisfação global com o trabalho é o comprometimento afetivo, sendo que quanto maior este último maior a satisfação com o trabalho. As implicações teóricas destes resultados são abordadas e discutidas.

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Three gypsiferous-calcareous soils from the Al-Hassa Oasis in Saudi Arabia were examined to determine the conditions under which dissolution of gypsum could be hindered by the formation of coatings of calcite during leaching. Batch extraction with water of a sandy clay loam, a sandy clay and a sandy loam containing 40, 26 and 5% gypsum and 14, 12 and 13% calcite respectively was followed by chemical analysis of the extracts, SEM examination and XRD and EDX microprobe analysis. Extraction in closed centrifuge tubes for I h or 5 h showed that initially gypsum dissolved to give solutions near to equilibrium but then in the sandy clay loam, between one quarter and one third of the gypsum could not dissolve. In the sandy clay about one fifth of the gypsum could not dissolve with none remaining in the sandy loam. All the extracts were close to equilibrium with calcite. SEM and EDX examination showed that coatings of calcite had formed on the gypsum particles. The sandy clay loam was also extracted using an open system in which either air or air +1% CO2 was bubbled through the suspensions for 1 h with stirring. The gypsum dissolved more rapidly and all of the gypsum dissolved. Thus, where the rate of dissolution of gypsum was rapid, calcite did not manage to cover the gypsum surfaces probably because the surface was being continuously removed. Slower leaching conditions in the field are likely to be conducive to the formation of coatings and less dissolution of gypsum. (c) 2006 Elsevier B.V. All rights reserved.

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Shallow groundwater beneath a former airfield site in southern England has been heavily contaminated with a wide range of chlorinated solvents. The feasibility of using bacterial biosensors to complement chemical analysis and enable cost-effective, and focussed sampling has been assessed as part of a site evaluation programme. Five different biosensors, three metabolic (Vibrio fischeri, Pseudomonas fluorescens 10568 and Escherichia coli HB101) and two catabolic (Pseudomonas putida TVA8 and E. coli DH5alpha), were employed to identify areas where the availability and toxicity of pollutants is of most immediate environmental concern. The biosensors used showed different sensitivities to each other and to the groundwater samples tested. There was generally a good agreement with chemical analyses. The potential efficacy of remediation strategies was explored by coupling sample manipulation to biosensor tests. Manipulation involved sparging and charcoal treatment procedures to simulate remediative engineering solutions. Sparging was sufficient at most locations. (C) 2004 Elsevier Ltd. All rights reserved.

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Gallaborane (GaBH6, 1), synthesized by the metathesis of LiBH4 with [H2GaCl]n at ca. 250 K, has been characterized by chemical analysis and by its IR and 1H and 11B NMR spectra. The IR spectrum of the vapor at low pressure implies the presence of only one species, viz. H2Ga(μ-H)2BH2, with a diborane-like structure conforming to C2v symmetry. The structure of this molecule has been determined by gas-phase electron diffraction (GED) measurements afforced by the results of ab initio molecular orbital calculations. Hence the principal distances (rα in Å) and angles ( α in deg) are as follows: r(Ga•••B), 2.197(3); r(Ga−Ht), 1.555(6); r(Ga−Hb), 1.800(6); r(B−Ht), 1.189(7); r(B−Hb), 1.286(7); Hb−Ga−Hb, 71.6(4); and Hb−B−Hb, 110.0(5) (t = terminal, b = bridging). Aggregation of the molecules occurs in the condensed phases. X-ray crystallographic studies of a single crystal at 110 K reveal a polymeric network with helical chains made up of alternating pseudotetrahedral GaH4 and BH4 units linked through single hydrogen bridges; the average Ga•••B distance is now 2.473(7) Å. The compound decomposes in the condensed phases at temperatures exceeding ca. 240 K with the formation of elemental Ga and H2 and B2H6. The reactions with NH3, Me3N, and Me3P are also described.

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This investigation determines the accuracy of estimation of methanogenesis by a dynamic mechanistic model with real data determined in a respiration trial, where cows were fed a wide range of different carbohydrates included in the concentrates. The model was able to predict ECM (Energy corrected milk) very well, while the NDF digestibility of fibrous feed was less well predicted. Methane emissions were predicted quite well, with the exception of one diet containing wheat. The mechanistic model is therefore a helpful tool to estimate methanogenesis based on chemical analysis and dry matter intake, but the prediction can still be improved.

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The aim of this study is to analyse the vascular flora and the local climate along an altitudinal gradient in the Lefka Ori massif Crete and to evaluate the potential effects of climate change on the plant diversity of the sub-alpine and alpine zones. It provides a quantitative/qualitative analysis of vegetation-environment relationships for four summits along an altitude gradient on the Lefka Ori massif Crete (1664-2339 m). The GLORIA multi-summit approach was used to provide vegetation and floristic data together with temperature records for every summit. Species richness and species turnover was calculated together with floristic similarity between the summits. 70 species were recorded, 20 of which were endemic, belonging to 23 different families. Cretan endemics dominate at these high altitudes. Species richness and turnover decreased with altitude. The two highest summits showed greater floristic similarity. Only 20% of the total flora recorded reaches the highest summit while 10% is common among summits. Overall there was a 4.96 degrees C decrease in temperature along the 675 m gradient. Given a scenario of temperature increase the ecotone between the sub-alpine and alpine zone would be likely to have the greatest species turnover. Southern exposures are likely to be invaded first by thermophilous species while northern exposures are likely to be more resistant to changes. Species distribution shifts will also depend on habitat availability. Many, already threatened, local endemic species will be affected first.