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211.
In this work we propose a new approach based on fuzzy concepts and heuristic reasoning to deal with the visual data association problem in real time, considering the particular conditions of the visual data segmented from images, and the integration of higher-level information in the tracking process such as trajectory smoothness, consistency of information, and protection against predictable interactions such as overlap/occlusion, etc. The objects’ features are estimated from the segmented images using a Bayesian formulation, and the regions assigned to update the tracks are computed through a fuzzy system to integrate all the information. The algorithm is scalable, requiring linear computing resources with respect to the complexity of scenarios, and shows competitive performance with respect to other classical methods in which the number of evaluated alternatives grows exponentially with the number of objects.  相似文献   
212.
Coal mine water (CMW) is typically treated to remove suspended solids, acidity, and soluble metals, but high concentrations of total dissolved solids (TDS) have been reported to impact the environment at several CMW discharge points. Consequently, various states have established TDS wastewater regulations and the US EPA has proposed a benchmark conductivity limit to reduce TDS impacts in streams near mining sites. Traditional CMW treatment effectively removes some TDS components, but is not effective in removing major salt ions due to their higher solubility. This paper describes the basic principles, effectiveness, advantages, and disadvantages of various TDS removal technologies (adsorption, bioremediation, capacitive deionization, desalination, distillation, electrochemical ion exchange, electrocoagulation, electrodialysis, ion exchange, membrane filtration, precipitation, and reverse osmosis) that have at least been tested in bench- and pilot-scale experiments.  相似文献   
213.
This study investigated the effects of change in exposure to peer and adult drinking on changes in positive alcohol expectancies during adolescence. Covariance and mean structure analysis were used to model change in the predictors and in alcohol expectancies in a sample of southern California schoolchildren followed from Grades 5 to 10 (N?=?3,580). The sample was gender balanced and was predominantly White (51 %) and Hispanic (28%). Exposure to peer drinking and rate of change in exposure to peer and adult drinking were found to predict the rate of change in alcohol expectancies. These effects were particularly strong between Grades 5 and 7, suggesting the need for early intervention aimed to prevent the increase in positive alcohol expectancies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
214.
Cryocoolers’ vibrations prevent them from being used in some sensitive applications. Stopping the cryocooler even for a short period gives rise to a steep drift of temperature. Such a drift can be significantly attenuated by adding an enthalpy reservoir to the cryocooler, separated from its cold finger by a heat switch. The whole assembly for the enthalpy reservoirs and switch is here called ESU, the energy storage unit. Two units have been built and tested based on solid state materials. One unit was designed to work up to 20 K, the other up to 6 K. This paper presents the experimental results obtained for both ESUs.Lead was used for the 20 K ESU while the ceramic GOS (Gd2O2S) was found adequate for the 6 K ESU. After stopping the cryocooler, a fairly slow temperature drift was measured at each ESU (from 11 to 20 K or from 3 to 6 K, respectively) while applying 10 mW for one hour, for instance. Otherwise, a temperature controlled platform experiment can use an ESU as a cold source allowing a constant temperature. Input power to the ESUs was monitored along with temperature and time. In the case of the 20 K ESU, calculations match the stored amount of energy as well as the temperature drift of the energy reservoir.A study for a high enthalpy intercept at the middle of the switch is also presented here. This intercept shall allow the attenuated temperature drift to hold for longer times. A cryogenic experiment can then be carried on using a cryocooler in a completely silent environment.  相似文献   
215.
The chemistry of the Maillard reaction involves a complex set of steps, and its interpretation represents a challenge in basic and applied aspects of Food Science. Fluorescent compounds have been recognized as important early markers of the reaction in food products since 1942. However, the recent advances in the characterization of fluorophores' development were observed in biological and biomedical areas. The in vivo non-enzymatic glycosylation of proteins produces biological effects, promoting health deterioration. The characteristic fluorescence of advanced glycosylation end products (AGEs) is similar to that of Maillard food products and represents an indicator of the level of AGE-modified proteins, but the structure of the fluorescent groups is, typically, unknown. Application of fluorescence measurement is considered a potential tool for addressing key problems of food deterioration as an early marker or index of the damage of biomolecules. Fluorophores may be precursors of the brown pigments and/or end products. A general scheme of the Maillard reaction is proposed in this article, incorporating the pool concept. A correct interpretation of the effect of environmental and compositional conditions and their influences on the reaction kinetics may help to define the meaning of fluorescence development for each particular system.  相似文献   
216.
Studies using a model of non-infectious diarrhea, have shown that increasing fecal mass by using laxatives resulted in greater fecal losses of nutrients and lower intestinal absorption. In the present study we used a diuretic to determine if increasing urine volume could result in greater urinary losses of essential nutrients. This is a relevant question because diuretics are widely and successfully used in the treatment of diseases associated with water retention and hypertension. They are known to increase potassium losses. However, there is less information on the effect of diuretics on the urinary losses of essential nutrients. Accordingly, urinary nitrogen, phosphorous, sodium, potassium, magnesium, zinc and retinol were measured in young rats consuming increasing concentrations of furosemide (0, 0.5, 1.0, 1.5 mg/g diet) in the diet over 15 days. The results showed that dietary furosemide caused a dose-dependent polyuria. In addition it reduced food intake and feed efficiency and leaded to poor growth and greater urinary losses of all the measured nutrients and electrolytes. These losses were proportional to urine volume and represented an important fraction of the rats daily intake. The losses were negatively associated with the body and liver content of the same electrolytes and nutrients. In general, this study showed that the diuretic furosemide caused malnutrition in a short period of time by reducing food intake as well as the capacity of retaining macro and micronutrients including the liposoluble vitamin A in a relatively short period of time. This study, together with our previous studies on diarrhea, indicate that proper nutrient utilization requires both an adequate intestinal and renal function.  相似文献   
217.
Students are characterized by different learning styles, focusing on different types of information and processing this information in different ways. One of the desirable characteristics of a Web-based education system is that all the students can learn despite their different learning styles. To achieve this goal we have to detect how students learn: reflecting or acting; steadily or in fits and starts; intuitively or sensitively. In this work, we evaluate Bayesian networks at detecting the learning style of a student in a Web-based education system. The Bayesian network models different aspects of a student behavior while he/she works with this system. Then, it infers his/her learning styles according to the modeled behaviors. The proposed Bayesian model was evaluated in the context of an Artificial Intelligence Web-based course. The results obtained are promising as regards the detection of students’ learning styles. Different levels of precision were found for the different dimensions or aspects of a learning style.  相似文献   
218.
Olanzapine (OLZ) is a commonly antipsychotic used to treat schizophrenia, a mental illness, with fewer side effects when compared with other drugs of the same class. It is commercialized mainly as oral tablets and orally disintegrating tablets. However, this drug oral bioavailability is affected by the first pass effect and low solubility in water. This requires high daily doses that can cause more side effects and poor treatment compliance. Also, the frequency of frequency of tablet intake is commonly related to patients' abandonment of schizophrenia treatment. So, the development of implantable biomaterials for OLZ delivery can be an alternative to solve both problems, since this material can, potentially, be used subcutaneously in less frequent administrations, thus the treatment has a greater chance of success. Therefore, the objective of this work was to produce polycaprolactone (PCL) rods incorporated with OLZ by hot-melt extrusion technique. The rods were characterized by different techniques, which showed an amount of 6.78 ± 0.56 mg of OLZ per rod. The in vitro release studies were performed and they showed a controlled release of the drug that followed the Higuchi's model. These results indicated that the PCL/OLZ rods have potential application in the schizophrenia treatment.  相似文献   
219.
Degradation of aqueous solutions of camphor by heterogeneous photocatalysis   总被引:1,自引:0,他引:1  
In this study the photocatalytic degradation of aqueous solutions of camphor was investigated by using TiO2 and ZnO photocatalysts. In the presence of artificial UV-light the highly photosensitive camphor was almost totally degraded after reaction times of 60 min. However, under these conditions the mineralization degree was lower than 25%. In the presence of semiconductors the degradation was complete after a treatment time of about 30 min. Moreover, the mineralization was considerably greater, mainly with the use of TiO2 (> 80% at reaction time of 60 min). Heterogeneous photocatalytic processes applied in the presence of solar radiation show a promising degradation capability. TiO2-based processes afforded mineralization degrees of about 90% after a reaction time of 120 min, when the system was assisted by aeration.  相似文献   
220.

Catalysts were prepared by impregnation of Fe2(MoO4)3 with different quantities of antimony butoxide. BET surface area measurement, XRD, Mössbauer spectroscopy, CTEM-AEM, XPS and ISS were used to characterize phase and surface architectures and their changes after calcination and catalytic reaction. Before calcination, antimony was present as pure oxide or hydroxide, partly as particles and partly as an incomplete monolayer on the surface of Fe2(MoO4)3. After calcination at 400°C, antimony got detached from the Fe2(MoO4)3 surface and aggregated very intensively, partly as Sb2O4 and partly, through reaction with the iron molybdate, as a mixture of distorted FeSbO4 and MoO3. After reaction or calcination at 500°C, more distorted FeSbO4 and MoO3 are formed, separated from Fe2(MoO4)3. Selective oxidation of isobutene to methacrolein was carried out on the calcined material. Impregnated catalysts show considerably improved catalytic performances compared to the pure Fe2(MoO4)3 phase or mechanical mixtures of it with α-Sb2O4. The catalytic performances are explained by several catalytic cooperations via spillover oxygen. These cooperative effects involve all the oxide phases present in the material having worked as catalyst: Fe2(MoO4)3 (pure or possibly contaminated by small amounts of antimony oxide), FeSbO4, MoO3 and SbyOx.

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