898 resultados para Total-energy Calculations
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In order to evaluate the interactions between Au/Cu atoms and clean Si(l 11) surface, we used synchrotron radiation grazing incidence X-ray fluorescence analysis and theoretical calculations. Optimized geometries and energies on different adsorption sites indicate that the binding energies at different adsorption sites are high, suggesting a strong interaction between metal atom and silicon surface. The Au atom showed higher interaction than Cu atom. The theoretical and experimental data showed good agreement. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.
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We employed the Density Functional Theory along with small basis sets, B3LYP/LANL2DZ, for the study of FeTIM complexes with different pairs of axial ligands (CO, H(2)O, NH(3), imidazole and CH(3)CN). These calculations did not result in relevant changes of molecular quantities as bond lengths, vibrational frequencies and electronic populations supporting any significant back-donation to the carbonyl or acetonitrile axial ligands. Moreover, a back-donation mechanism to the macrocycle cannot be used to explain the observed changes in molecular properties along these complexes with CO or CH(3)CN. This work also indicates that complexes with CO show smaller binding energies and are less stable than complexes with CH(3)CN. Further, the electronic band with the largest intensity in the visible region (or close to this region) is associated to the transition from an occupied 3d orbital on iron to an empty pi* orbital located at the macrocycle. The energy of this Metal-to-Ligand Charge Transfer (MLCT) transition shows a linear relation to the total charge of the macrocycle in these complexes as given by Mulliken or Natural Population Analysis (NPA) formalisms. Finally, the macrocycle total charge seems to be influenced by the field induced by the axial ligands. (C) 2011 Elsevier Ltd. All rights reserved.
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A tool for standardized calculation of solar collector performance has been developed in cooperation between SP Technical Research Institute of Sweden, DTU Denmark and SERC Dalarna University. The tool is designed to calculate the annual performance of solar collectors at representative locations in Europe. The collector parameters used as input in the tool are compiled from tests according to EN12975, without any intermediate conversions. The main target group for this tool is test institutes and certification bodies that are intended to use it for conversion of collector model parameters (derived from performance tests) into a more user friendly quantity: the annual energy output. The energy output presented in the tool is expressed as kWh per collector module. A simplified treatment of performance for PVT collectors is added based on the assumption that the thermal part of the PVT collector can be tested and modeled as a thermal collector, when the PV electric part is active with an MPP tracker in operation. The thermal collector parameters from this operation mode are used for the PVT calculations. © 2012 The Authors.
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An expedited permitting area has been created to facilitate the development of wind power projects in Maine. The purpose of this project was to investigate the impact of removing areas of conservation interest from the expedited permitting area. We found that the removal of these areas impacts the total wind potential of the state, in an amount proportional to the size of the area removed. The impact on the total wind potential ranged from 0.46-29.0% decrease, depending on the calculation scenario used. These findings may have implications for future policy decisions concerning wind power development.
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The continuous search of the increase of the productivity has been facilitating the growing diffusion of modern and advanced technologies, that open new ways for the renovation of the industrial productive process, as well as, to the appearance of modern administration systems that establish ways in direction to the democratization of the social relationships in the organizations. Accompanying that tendency and, motivated by the competitive characteristic of the market of electric energy, Eletronorte, adopted the Total Productive Maintenance - TPM, of japanese origin, as the system of administration of its productive process. This dissertation has as objective, to analyze the methodological content of the Total Productive Maintenance, showing its significance and its reach in the Regional of Transmission of Mato Grosso, adopting the post fordism, as comparison paradigm. The whole study and analysis had as focus the offices of the company and the Substation of Coxipó, placed in the city of Cuiabá, as well as the Substations of Rondonópolis and Sinop, placed in cities with the same name. The offices and the substations are geographically located in the state of Mato Grosso, and under the responsibility of the Regional of Transmission of Mato Grosso, of the Centrais Elétricas do Norte do Brasil SA - Eletronorte. The work method was of qualitative orientation and of case study, through a research of applied nature. The research was accomplished with explanatory and exploratory objectives. They were used as instruments of collection of data the analysis of documents, interviews, and application of questionnaires. The data collected through documents and of the application of questionnaires they were compiled and analyzed. The results of the interviews had for objective to confirm the consistency of the collected data. The obtained results demonstrate increases of productivity of the order of 40%, and reduction of the costs of up to 29%. The study still demonstrated, that TPM provoked significant impacts in the practices you work, denoting the presence of an action managerial dialógica. It was still characterized that the transference of TPM will depend in that context the administration system will be applied, because if this is here different from it studied, there won't be transference warranties.
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Produção intelectual e desenvolvimento tecnológico podem diferenciar países e regiões no processo de desenvolvimento socioeconômico. No caso do Brasil, observa-se o papel energético do etanol combustível para veículos motorizados leves como um resultado importante do avanço tecnológico do país, que vai além da aptidão agroclimática. A contínua busca pela especialização tecnológica verticalizada do setor sucroenergético poderia levar o Brasil a uma posição, se não autônoma, mais confortável, não só de produtor de matéria-prima, mas de processos agregadores de valor no que diz respeito aos processos de produção de etanol de segunda geração, produzido a partir de biomassa lignocelulósica. O objetivo desta dissertação é analisar os esforços de P&D que resultaram em Depósitos e Publicações de patentes em órgãos oficiais como o United States Patent and Trademark Office (USPTO), o European Patent Office (EPO), e o Instituto Nacional de Propriedade Industrial (INPI), no tema etanol de segunda geração. Ainda, verifica-se se esses esforços impactam no poder concorrencial de países e firmas depositantes de patentes. Além das coletas e observações dos dados dos órgãos acima mencionados, foram calculados para os dados de depósitos e publicações de patentes no tema bioetanol lignocelulósico os índices de Herfindahl Hirschman (HHI) e a razão de concentração (Concentration Ratio) CR4, tradicionalmente utilizados para que órgãos reguladores de defesa do consumidor autorizem fusões e aquisições entre participantes de um determinado mercado. Esse método permite a observação do grau de competitividade entre as firmas depositantes de patentes no tema e a possível tendência sobre a detenção do controle em futuro próximo e a corrida para venda de royalties dos processos desenvolvidos em diferentes áreas tecnológicas para incrementar a produção industrial de etanol avançado. Os resultados indicam uma concentração elevada dos esforços de pesquisa, medidos pelos depósitos de patentes, referentes a etanol de segunda geração, em um número muito reduzido de empresas norte-americanas, quando analisada a base de dados dos EUA. O sucesso desses esforços, mensurados pela publicação de patentes, contudo, não se mostra concentrado nem nos EUA nem na União Europeia. No caso do Brasil, ainda não são encontradas publicações de patentes no tema Lignocellulosic Bioethanol, bem como apenas uma empresa brasileira possui uma patente publicada nos Estados Unidos. Esses resultados sugerem que investimentos em pesquisa científica no Brasil podem produzir mais artigos publicados e titulação acadêmica/científica que propriamente o registro de patentes em órgãos especializados em qualificar a invenção de métodos, processos ou fórmulas, dentro e fora do país. Isso pode significar tanto baixo esforço em pesquisa no assunto quanto à perda pelo autor e/ou sua instituição da oportunidade de ter seu esforço de pesquisa recompensado por meio de royalties, como compensação pela criatividade, dedicação intelectual e de recursos econômicos. Os resultados deste estudo contribuem para o debate a respeito da crescente necessidade de produção e abastecimento de fontes renováveis de energia, como o biocombustível etanol avançado à base do derivado bagaço de cana-de-açúcar, a custos mais competitivos como matéria-prima adicional e para produção incremental de etanol em futuro próximo. As conclusões do estudo indicam a necessidade do aumento na produção de conhecimento aplicado e em esforços para garantir sua propriedade intelectual, permitindo o retorno patrimonial com royalties.
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Over the past few years, renewable energy subsidies have become one of the main sources of trade disputes in the WTO. A total of six cases have been initiated against renewable energy subsidy programs since the first of such disputes was brought by Japan against Canada’s Feed in Tariff (FIT) program in 2010. Yet not even a single case has so far been initiated against the much larger and environmentally harmful fossil fuel subsidies. The main objective of this paper is to examine what makes renewable energy subsidies vulnerable to WTO dispute, as compared fossil fuel subsidies.
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In this dissertation, the theoretical principles governing the molecular modeling were applied for electronic characterization of oligopeptide α3 and its variants (5Q, 7Q)-α3, as well as in the quantum description of the interaction of the aminoglycoside hygromycin B and the 30S subunit of bacterial ribosome. In the first study, the linear and neutral dipeptides which make up the mentioned oligopeptides were modeled and then optimized for a structure of lower potential energy and appropriate dihedral angles. In this case, three subsequent geometric optimization processes, based on classical Newtonian theory, the semi-empirical and density functional theory (DFT), explore the energy landscape of each dipeptide during the search of ideal minimum energy structures. Finally, great conformers were described about its electrostatic potential, ionization energy (amino acids), and frontier molecular orbitals and hopping term. From the hopping terms described in this study, it was possible in subsequent studies to characterize the charge transport propertie of these peptides models. It envisioned a new biosensor technology capable of diagnosing amyloid diseases, related to an accumulation of misshapen proteins, based on the conductivity displayed by proteins of the patient. In a second step of this dissertation, a study carried out by quantum molecular modeling of the interaction energy of an antibiotic ribosomal aminoglicosídico on your receiver. It is known that the hygromycin B (hygB) is an aminoglycoside antibiotic that affects ribosomal translocation by direct interaction with the small subunit of the bacterial ribosome (30S), specifically with nucleotides in helix 44 of the 16S ribosomal RNA (16S rRNA). Due to strong electrostatic character of this connection, it was proposed an energetic investigation of the binding mechanism of this complex using different values of dielectric constants (ε = 0, 4, 10, 20 and 40), which have been widely used to study the electrostatic properties of biomolecules. For this, increasing radii centered on the hygB centroid were measured from the 30S-hygB crystal structure (1HNZ.pdb), and only the individual interaction energy of each enclosed nucleotide was determined for quantum calculations using molecular fractionation with conjugate caps (MFCC) strategy. It was noticed that the dielectric constants underestimated the energies of individual interactions, allowing the convergence state is achieved quickly. But only for ε = 40, the total binding energy of drug-receptor interaction is stabilized at r = 18A, which provided an appropriate binding pocket because it encompassed the main residues that interact more strongly with the hygB - C1403, C1404, G1405, A1493, G1494, U1495, U1498 and C1496. Thus, the dielectric constant ≈ 40 is ideal for the treatment of systems with many electrical charges. By comparing the individual binding energies of 16S rRNA nucleotides with the experimental tests that determine the minimum inhibitory concentration (MIC) of hygB, it is believed that those residues with high binding values generated bacterial resistance to the drug when mutated. With the same reasoning, since those with low interaction energy do not influence effectively the affinity of the hygB in its binding site, there is no loss of effectiveness if they were replaced.
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Infections for intestinal parasites are one of the main morbidade causes in humans and, its relationships with socioeconomic levels and hygiene conditions in countries in development are already very established. Many works, even so, they are being accomplished to elucidate the complex interactions among nutrition, these infections and answer imunológica, because it is seen that malnutrition commits the immunity increasing the susceptibilidade for infectious diseases and these for its time can harm the state human nutricional. It is known that sponge helmínticos they stimulate synthesis of IgE so much policlonal as specific for the same ones and that IgA secretora, main imunoglobulina of defense of the mucous ones, can act against protozoa as the Giardia lamblia and against helmintos as Trichuris tichiura and Strongyloides stercorales. Some studies show that the malnutrition energy protéica influences in the production of these answers, but some authors show results divergentes. In this work it was evaluated the levels of total IgE, IgA sérica and secretora, contagem of sanguine eosinófilos, levels of proteins séricas and state nutricional, in 103 children of low socioeconomic level, to discover a correlation between those and infection for enteroparasitas. They participated in the study children of both sexes, with age of 3 to 6 years, visitors of the same creche and residents in a neighborhood with precarious hygiene conditions and basic saneamento, in the city of Christmas. The obtained results showed that the faulty environmental and socioeconomic conditions favored to a high infection frequency for enteroparasitas, mainly Trichuris trichiura and Ascaris lumbricoides between the helmintos and Endolimax sleep and Giárdia lamblia among the protozoa. Light malnutrition without deficit protéico was observed in 30% of the children, which didn't also present significant deficiencies of IgA sérica and secretora. The sponged children
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Maize gluten feed (MGF) is a co-product of wet milling of maize, and is composed of structures that remain after most starch, gluten and germ has been extracted from the grain. Although currently used in dog foods, its digestibility and energy values have not been documented. Two techniques were used to determine nutrient digestibility of MGF for dog foods. Both techniques used extruded diets fed to Beagle dogs, with six replicates per diet. The first study used a difference method in which 300 g/kg of a reference diet was replaced by MGF. Based on the difference method, the coefficient of total tract apparent digestibility (CTTAD) of MGF was 0.53 for dry matter (DM), 0.69 for crude protein (CP), 0.74 for fat, 0.99 for starch, and 0.55 for gross energy (GE). The calculated metabolizable energy (ME) of MGF was 7.99 MJ/kg (as-fed). The second study used a regression method and included a basal diet and a basal diet with 70, 140 and 210 g MGF/kg of diet (as a substitute for maize starch). Maize gluten feed inclusion resulted in a linear reduction of CTTAD of DM (R(2)=0.99; P<0.001), CP (R(2)=0.95; P=0.002), fat (R(2)=0.87; P=0.009). starch (R(2)=0.81; P<0.001), and GE (R(2)=0.99; P<0.001). Faecal production increased linearly from 56 g to 107 g/dog/d (R(2)=0.99; P<0.001), with a linear reduction of faecal DM (R(2)=0.99: P<0.001) and a linear increase in faecal lactic acid concentration (P<0.02). Both urine (R(2)=0.77; P=0.029) and faeces (R(2)=0.92: P=0.019) showed a linear reduction in pH. Results of ingredient MAD obtained by the regression and difference methods were close (6% or less of variation) for CP, fat, and starch, and also for ME content (1.4% higher for the difference method), but the two methods disagreed on calculated CTTAD of DM and organic matter. The high dietary fiber content of MGF (382 g/kg) may explain the low digestibility of this ingredient. Maize gluten feed could be a useful ingredient for formulations designed to have low energy or reduce the urine pH of dogs. (C) 2011 Elsevier B.V. All rights reserved.
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O experimento foi realizado com o objetivo de avaliar as digestibilidades parcial e total das frações digestíveis de dietas com feno de capim-marandu e concentrado utilizando-se a fibra em detergente ácido indigestível como indicador. Foram utilizados quatro tourinhos da raça Santa Gertrudes, canulados no rúmen e duodeno, distribuídos em delineamento quadrado latino 4 x 4. As dietas foram ajustadas para que os animais tivessem ganhos diários de peso corporal (GPC) de 0,5 e 1 kg/animal, associado a potenciais de fermentação microbiana de 9,5 e 11 g de PB microbiana/MJ em fermentável. Houve efeito das dietas ajustadas para potencial de GPC sobre as ingestões diárias de MS (7,05 e 8,07 kg/animal, respectivamente para 0,5 e 1,0 kg/animal de GPC), mas não daquelas balanceadas para potencial de fermentação microbiana (7,57 kg/animal). O tratamento para GPC diário de 1 kg/animal proporcionou maior digestibilidade total da matéria orgânica e de carboidratos totais (médias de 66,63 e 58,68%, respectivamente) quando comparado ao tratamento para GPC diário de 0,5 kg/animal, que apresentou, para as mesmas variáveis, médias de 61,57 e 53,94%. Os resultados não justificaram a utilização de dietas para maior potencial de fermentação microbiana. As dietas balanceadas para altos ganhos de peso, no entanto, mostraram-se melhores quanto à ingestão e ao aproveitamento dos nutrientes que as formuladas para baixos ganhos de peso.
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This study was designed to evaluate the effect of nutritional supplementation offered during the pre- and postpartum periods on serum cholesterol, triglycerides and total lipids of Canchim beef cows and their relationship with folliculogenesis. Thirty cows with predicted calving date between September and October, kept in pastures of Brachiaria brizantha cv. Marandu together with their calves, were randomly distributed into three experimental groups: the first received only a mineral mixture (Control Group, CG); the second group received a concentrate with 16% crude protein/kg dry matter (DM) and 3000 kcal digestible energy/kg DM offered for 45 days prepartum and 120 days postpartum (PREG); the third group received the concentrate from parturition until the 120th day postpartum (POSG). Consumption was estimated at 1% of body weight, and each cow received approximately 4.0 kg/day (fresh weight) of supplement. Blood samples were taken and an ultrasound examination of the ovaries was performed twice a week until the 60th day postpartum. The body condition score (BCS) and the weight of the cows were recorded at 15-day intervals from calving until the 60th day postpartum. Data are presented as mean +/- SEM. Mean weight and BCS at calving were, respectively, 448 +/- 54.9 kg and 6.2 +/- 0.25 (PREG); 432 +/- 71.1 kg and 5.5 +/- 0.69 (POSG); and 434 +/- 66.4 kg and 5.5 +/- 0.69 (CG). Total cholesterol (TC), triglycerides (TRIG) and total lipids (TLIP) were measured using colorimetry until the 60th day postpartum. TC averages were PREG 186 +/- 62.6 mg/dL, POSG 159 +/- 43.1 mg/dL and CG 133 +/- 35.1 mg/dL (P < 0.05). For TRIG, the means were PREG 29 +/- 11.3 mg/dL (P < 0.05), POSG 24 +/- 8.1 mg/dL and CG 26 +/- 12.1 mg/dL (P > 0.05). Serum concentrations of TLIP were PREG 588 +/- 145.6 mg/dL, POSG 512 +/- 137.6 mg/dL and CG 452 +/- 122.4 mg/dL (P < 0.05). The first dominant follicle (DF) was identified on Day 21 +/- 10.3 (PREG), 36 +/- 28.5 (POSG) and 51 +/- 32.8 (CG) after calving. The difference between PREG and CG was significant (P < 0.05). TC was positively correlated with the calving to first estrus interval (P < 0.05). Results showed that nutritional supplementation before parturition assured good body condition at calving and suggested that it was effective at increasing cholesterol availability to maintain ovarian follicle function and to favor earlier resumption of ovarian activity. (C) 2010 Published by Elsevier B.V.
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The objective of the present study was to evaluate the effects of different dietary energy levels and stocking densities on the thermoregulating parameters, live performance, and carcass traits of broilers reared under tropical winter conditions at different times of the day. In total, 1,312 one-d-old male broilers were used. Birds were allotted to three different stocking densities (10, 14 or 18 birds/m²) and two dietary energy levels (2900 or 3200 kcal ME/kg). The following parameters were evaluated:radiant heat load (RHL), rectal temperature (RT), feed intake (FI), weight gain (WG), feed conversion ratio (FCR), livability (L), production of live weight per area (WA), and carcass yield. Stocking density did not affect sensible heat loss (SRL) or rectal temperature (RT); however, as expected, sensible heat loss (SRL) and RT were influenced by time of the day, with higher values in the morning and in the afternoon, respectively. There was no effect of treatment (p>0.05) on carcass or parts yield. Feed intake was reduced in 3%, whereas weight gain and feed conversion ratio improved in 8 and 10%, respectively, as dietary energy level increased. on the other hand, stocking density did not influence live performance or carcass traits. Based on the present results, it is concluded that sensible heat loss depends on dietary energy levels and particularly on time of the day. Therefore, environmental house management is suggested during tropical winters in order to reduce differences between broiler skin and environmental temperatures in the morning and in the afternoon.