785 resultados para Lighter trivalent lanthanides
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Thermogravimetry (TG) up to 900°C, differential thermal analysis (DTA) up to 1100°C and gravimetric data up to 1200°C, have been used to study the thermal decomposition of ammonium selenate and of the double selenates of lanthanides, and yttrium, and ammonium. The results provided the composition and thermal stability and also an interpretation of the thermal decomposition mechanisms. © 1994.
Resumo:
Solid state chelates of general formula H[Ln(EDTA)] · nH2O (Ln = trivalent lanthanide (except for promethium) or yttrium; EDTA = ethylenediaminetetraacetate) were prepared. Thermogravimetry, differential thermal analysis. X-ray diffraction and complexometry were used to characterize and study the thermal stability and thermal decomposition of these compounds. © 1993.
Resumo:
The technique proposed aims at reducing the weight of individualized ample ocular prostheses using acrylic resins as well as simplifying laboratory procedure. For that, prefabricated hollow spheres made of plastic material, were inserted in the sclera. The average weights of the solid conventional sclera (5.30g) and those of the respective prefabricated plastic ones (3.91g) were compared. The weight reduction was significative with a confidence interval of 95% by the Student t test. ln addition, for illustration purpose, the technique was applied to patients in the ward of the Maxillofacial Prostheses Dicipline of the Dentistry School in the Campus of São José dos Campos - UNESP, having each patient received a solid prosthesis and a hollow prefabricated one made of plastic material. It has been concluded that the prostheses material spheres were inserted are lighter than the ones which received solid spheres; furthermore, thr technique is viable for ample anophtalmic cavities and requires few sessions
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Brazil is the world’s first chicken meat exporter nowadays. The maintenance of this position requires a constant quality attributes evolution. This work evaluated the chicken meat consumer profile in the northwest region of São Paulo state, the most important Brazilian poultry meat consumer market, in order to provide information to the productive sector. The data were collected using 482 interviews and questionnaires that were answered by e-mail. The questionnaires involved questions related to the consumer identification, habits and preferences and their knowledge about food safety, production system, sustainability and animal welfare. Most of the consumers, 62%, were female, with ages ranging from 20 to 50 years. Beef was preferred by the majority of the answerers and chicken and pork meat were together the second choice. Only 2% of the interviewed consumers mentioned not enjoying poultry meat. The main part of consumers, 67%, prefer to buy breast and leg cuts and only 11% are used to buy the whole poultry carcass. More than 60% of the interviewed have already eaten free range chicken meat, but the majority of them, 89%, are used to consume regular industrialized poultry. About 75% of the consumers believe hormones are used to grow the birds. Over 80% of people observe the expiration date before buying the product, but only 55% check if it has the stamp of the official inspection service. Color and appearance of meat are the most important factors that influence the consumer’s choice. The amount of water that drips on the tray is a rejection factor to 88% of answerers. Most of them, 66%, prefer lighter colored meat. Only 27% of them believe that chicken meat causes an environmental impact and 48% do not know the meaning of animal welfare. More than half of the interviewed do not consider animal welfare aspects before consuming any kind of meat. From these results obtained, it is possible to conclude that any effort to improve the product quality, mainly concerned to animal welfare and sustainability aspects, requires prior educational initiatives.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Forty eight piglets from a commercial strain weaned at an average age of 21 days were used in order to evaluate effects of carbohydrates sources (lactose or maltodextrin) and the weights of piglets at weaning on the stomach pH, colon and rectum contents, and the amount of total coliform, Escherichia coli and Lactobacillus spp in digesta of ileum and cecum. The experiment was conducted in a randomized block design and analyzed in split plot, considering class of weight and carbohydrates as main plots and the slaughter age of animal as sub-plots. The stomach pH and intestinal contents were not influenced by the diets provided as well as the amount of total coliform. It was found that the presence of lactose in the feed decreased counts of Escherichia coli and Lactobacillus ssp in the ileum. Regarding the class of weight, the lighter piglets had lower counts of Escherichia coli and Lactobacillus. The maltodextrin can be used as an alternative to replace the lactose in the diet, regardless of the piglets weight at weaning, as it does not adversely affect the pH and the Lactobacillus population in the gastrointestinal tract.
Resumo:
Physical activity has been scientifically discussed as fundamental in the process of healthy ageing. Hence, this study aimed at determining the factors that influence older people to perform physical activities. The complete IPAQ (International Physical Activity Questionnaire) was applied to a population-based sample consisting of 364 elderly persons in the city of Botucatu, São Paulo, Brazil. Days of physical activity performed by the older people were considered by taking into account household and leisure activities. Models for count data were fitted by including socio-demographic variables as well as those related to life satisfaction. It was shown that housework physical-activity performance is associated with female, who predominantly showed to be more active in all levels. Male seemed to be more predisposed to perform lighter recreation, sports and leisure-time physical activities, such as walking. Additionally, poor schooling showed to be decisive for not performing physical activities both at home and during leisure.
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Varying economic conditions and changes in the demands of the meat consuming public have been responsible for the turns that have taken place in the beef industry during recent years. Both feeder and producer must recognize and conform to these changes if they are to continue in business. Among the most important of these changes have been the turn toward the marketing of lighter cattle and the gradual disappearance from feed lots of two- and three-year-old animals. Furthermore, the cattle population of the United States is fast reaching stabilization with the resulting effect that more heifers are being marketed, since only one-fourth of the heifer crop is needed to replace worn-out breeding animals. Realizing the increasing importance of the heifer problem from the standpoint of the producer, feeder, and consumer, the Nebraska Experiment Station undertook to compare steers and heifers in a series of trials both in the feedlot and in the beef. It was hoped that these experiments would yield results which would bring out existing differences, if any, between steers and heifers both in quality and quantity of beef produced and thus provide or disprove many of the complaints against heifers. The results of these trials are summarized in this bulletin. Age as well as the sex factor has been considered, since two-year-olds, yearlings, and calves were included in these trials.
Resumo:
Composites are engineered materials that take advantage of the particular properties of each of its two or more constituents. They are designed to be stronger, lighter and to last longer which can lead to the creation of safer protection gear, more fuel efficient transportation methods and more affordable materials, among other examples. This thesis proposes a numerical and analytical verification of an in-house developed multiscale model for predicting the mechanical behavior of composite materials with various configurations subjected to impact loading. This verification is done by comparing the results obtained with analytical and numerical solutions with the results found when using the model. The model takes into account the heterogeneity of the materials that can only be noticed at smaller length scales, based on the fundamental structural properties of each of the composite’s constituents. This model can potentially reduce or eliminate the need of costly and time consuming experiments that are necessary for material characterization since it relies strictly upon the fundamental structural properties of each of the composite’s constituents. The results from simulations using the multiscale model were compared against results from direct simulations using over-killed meshes, which considered all heterogeneities explicitly in the global scale, indicating that the model is an accurate and fast tool to model composites under impact loads. Advisor: David H. Allen
Resumo:
In Arkansas, blackbirds are responsible for appreciable damage to rice, grain sorghum, oats, wheat, rye, and corn. By far, the greatest damage is to rice. As is shown in the following table, the losses to rice producers amounted to an estimated $3,049,055 in 1968, the last year that a survey was made. Nearly two-thirds (63%) of this loss was to standing rice destroyed and to the cost of bird control measure in standing rice. The remaining losses ($2,140,320 ) are to seeding or to efforts to control bird depredations to new seeding, (see Table 1). Blackbird damage to grain sorghum and corn was mostly to standing grain; that to oats, wheat and rye, to seeding, although there is occasional damage to standing grain. Additional problems are caused by blackbirds in feed lots. The total losses to Arkansas agricultural producers due to blackbirds in 1968 was about $3,500,000. Bird damage in a specific locality and on specific crops seems to vary in intensity from year to year. However, surveys during the past ten years suggest a fairly consistent level of total damage state-wide. The damage in 1968-and I believe in 1969—was somewhat lighter than we have come to expect from past exper¬ience. (See table 2.) On a per acre basis the damage in 1968 showed a considerable decline when compared to previous years. A part of this decline is probably a temporary situation. Some of the decline in losses to rice and grain sorghum, however, are due to changes in varieties, such as development of bird-resistant milo, and to changes in cultural methods. Further appreciable reductions due to changes in these factors seem unlikely, (see table 3.) Since rice producers sustain the greatest losses to birds, they have generated the greatest demand for bird control programs. Three species are responsible for most of the damage to rice. They are the red-winged blackbird, common grackle and brown-headed cowbird. These birds have created problems for rice producers since the first successful rice crop was grown near Lonoke, Arkansas, in 1904.
Resumo:
The Community Climate System Model version 3 is used to analyse changes in water mass subduction rates in the South Atlantic Ocean over the 21st century. The model results are first compared to observations over 1950-2000, and shown to be rather good. The subduction rates do not change significantly over the 21st century, but the densities at which water masses form become significantly lighter. The strong westerly winds in this region do not change much, which suggests small changes to the rate at which the Atlantic sector of the Southern Ocean takes up heat and carbon dioxide over the 21st century.