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This report is the second part of a study on the nutrition of urban schoolchildren in the city of Manila; the first part was on nutritional status. The primary purpose of the study was to gather data that will assist authorities in planning and implementing nutrition education programs focused on the growing problem of obesity and overweight in children. The study included 1,208 children 8 to 10 years of age, who were randomly selected from all public and private schools in the city of Manila. Data on the children's dietary and physical activity patterns, together with information on nutrition-related knowledge, attitudes, and preferences of the children and their parents, were gathered by interviews and self-administered questionnaires. There were distinct differences in dietary and physical activity patterns between the two groups of children. Children from private schools, who are generally of higher socioeconomic status than those from public schools, tended to consume more total food, more animal foods, fats, and oils, and more beverages, resulting in higher intakes of calories, protein, iron, and vitamin A than public schoolchildren. Moreover, children from private schools were apparently less physically active, were more likely to be driven to school instead of walking, and were more likely to prefer television and computer games over outdoor games. These differences agree with an earlier report on the nutritional status of the children as determined by anthropometry, which showed a higher proportion of overnutrition and a lower proportion of undernutrition among private schoolchildren than among public schoolchildren. Although the emphasis in public schools should be on prevention and control of undernutrition in children, private schools should begin to look at the emerging problem of overnutrition and the role of physical activity programs in the health of children. The information on the knowledge, attitudes, and preferences of the children and their parents showed that parents or guardians, teachers, and television influence the nutritional practices of schoolchildren. These groups should therefore be the major targets for nutrition education programs meant to improve the nutrition and health of schoolchildren.  相似文献   
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The influence of vacuum time and solution concentration on mass transfer and mechanical properties of osmodehydrated melon cubes has been studied. Pulsed vacuum osmotic dehydration (PVOD) was carried out at 30 °C for 4 h, using sucrose solutions (40, 50 or 60°Brix) and applying a vacuum pulse (100 mbar for 5, 10 or 15 min). Kinetics of water loss, solid gain and stress at rupture were analysed, as well as effective diffusivities using the hydrodynamic model. The increase in solution concentration favoured water removal, but no significant effect of vacuum time was observed. The use of less concentrated solutions coupled to the action of vacuum pulse resulted in greater solid uptake. Samples subjected to PVOD using 60°Brix sucrose solution presented greater water loss, lower sugar uptake and better maintenance of fresh fruit texture throughout the process. Diffusion coefficients estimated by the hydrodynamic model showed a good fit to the experimental data.  相似文献   
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Psychrotrophic bacteria behaviour, when gamma irradiation is applied with shelf-life extension purposes to a fresh squid product, was modelled. In this regard, the effect of gamma irradiation at 0, 1.8, 3.3 and 5.8 kGy on psychrotrophic microorganisms in vacuum-packed squid (Illex argentinus) rings was analysed during storage at 4–5 °C. First-order kinetics satisfactorily described the radio-induced inactivation of the initial psychrotrophs population. The growth of surviving bacteria during storage was fitted to two empirical models: modified Gompertz model and a polynomial expression dependent on irradiation dose and storage time. In turn, the influence of irradiation dose on kinetic parameters of Gompertz model was described by second order polynomials. Both proposed models satisfactorily described the behaviour of psychrotrophs as affected by gamma irradiation, allowing accurate shelf-life predictions for doses up to 5.3 kGy. Considering the predictions accuracy, complete Gompertz model was preferred and model validation was done for irradiation at 4.8 kGy.  相似文献   
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ABSTRACT:  Banana is a starchy food that contains a high proportion of undigestible compounds such as resistant starch and nonstarch polysaccharides. Products with low glycemic response such as pasta are considered favorable to health. The objective of this study was to use unripe banana flour to make spaghetti with low-carbohydrates digestibility and evaluate its physical and texture characteristics, as well as consumer preference. Formulations with 100% durum wheat semolina (control) and formulations with 3 semolina: banana flour ratios (85: 15, 70: 30, and 55: 45) were prepared for spaghetti processing. The use of banana flour decreased the lightness and diameter of cooked spaghetti, and increased the water absorption of the product. Hardness and elasticity of spaghetti were not affected by banana flour, but adhesiveness and chewiness increased as the banana flour level in the blend rose. Spaghettis prepared in the laboratory (control and those with banana flour) did not show differences in preference by consumers. In general, the preference of spaghettis with different banana flour level was similar. The addition of a source of undigestible carbohydrates (banana flour) to spaghetti is possible without affecting the consumer preference.  相似文献   
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System Reliability-Based Design Optimization (RBDO) considers a single system failure probability constraint. The formulation allows different failure modes to compete with each other. Very few methods and benchmark examples involving optimal design considering system behaviour with progressive failure can be found in the literature. In this article, the conventional System RBDO formulation is compared with a risk-based formulation. A benchmark example involving progressive failure of hyper-static truss is addressed. It is demonstrated that typical System RBDO formulations always lead to isostatic structures, since the formulation does not offer any incentive for the permanence of hyper-static members. In the risk-based formulation, failure costs are differentiated with respect to primary member failure, in hyper-static structures (existence of warning before eventual collapse), and failure of isostatic members (no warning). In this formulation, optimal designs also include hyper-static structures. Results presented herein are relevant in the modern context of robust design considering progressive collapse.  相似文献   
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