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521.
522.
This work aimed to collect and study all milling fractions generated during an industrial rye milling technology and to select nutritionally promising subfractions for further investigations (chemical composition and rheological behaviour) also considering their yield. To investigate the varietal effect, four rye samples were examined and applied in the milling experiments. The results showed great variability of technological properties (mainly in viscous behaviour) among rye samples. Generally, subfractions had higher protein, lipid, total and soluble dietary fibre content than white flours, and several subfractions provided higher values even than wholemeal flours. Significant differences were found between the fractions in the mixing and viscous behaviour, which could be explained principally by the variable dietary fibre content and composition, however, the effect of protein content was found also prominent. The results pointed out that alternative milling products with favourable composition and technological properties can be produced by collecting appropriate subfractions.  相似文献   
523.
Software and Systems Modeling - The need for real-time collaborative solutions in model-driven engineering has been increasing over the past years. Conflict-free replicated data types (CRDT)...  相似文献   
524.
The accumulation of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and DDTs were investigated in gammarids captured at three sites along the middle River Po; the first was located upstream and the other two were at increasing distances downstream of the confluence of a polluted tributary, the River Lambro. Using a GC-MS technique, the levels of PCBs, PAHs and DDTs were determined separately in large and small gammarids as well as in the fine fraction of sediment samples collected along the sites of capture. Results confirm the River Lambro as a source of these chemicals to the River Po, and show that bioaccumulation differences exist between small and large individuals, the former being more contaminated particularly by PCBs and DDTs. This is likely the result of several interacting factors such as contaminant bioavailability, gammarid-size effects on kinetic parameters and feeding selectivity. The bioaccumulation patterns of PCBs and DDTs, and their higher biota-sediment accumulation factors (BSAF), are consistent with chemical properties and suggest a dietary disequilibrium found only 10 km downstream from the tributary, and in smaller amphipods. Present results show that gammarids may represent an additional source of contaminants, particularly of chlorinated compounds, to the many organisms feeding on them, with a higher risk for those which prey selectively on smaller gammarids.  相似文献   
525.
In this work, comparative analysis of processes in carbon arc and radio frequency (RF) plasma during fullerene synthesis has been presented. The kinetic model of fullerene formation developed earlier has been verified in both types of plasma reactors. The fullerene yield depended on carbon concentration, velocity of plasma flame and rotational temperature of C2 radicals predominantly. When mean rotational temperature of C2 radicals was 3000 K, the fullerene yield was the highest regardless of the type of used reactor. The zone of fullerene formation is larger significantly in RF plasma reactor compared to arc reactor.  相似文献   
526.
TENORM are found in a wide variety of waste materials, some raw mineral ores and in some consumer products (in trace amounts) where molecules of radionuclides may be bound to specific minerals used in the manufacturing process and can result in increases in radiation exposures to workers and the public. The aim of this paper is to understand this problem and to develop effective ways to protect humans and the environment from harmful exposure to the radiation in TENORM materials in the Vojvodina region. The results of measurement of indoor radon concentration in schools and kindergartens and dose-rate and gamma-spectrometry measurements of the workplace with TENORM materials are presented.  相似文献   
527.
The friction behaviour of five different gear oils in rolling–sliding and pure sliding contacts and how temperature influences their friction properties were investigated. It is found that increasing temperature decreases boundary friction with gear oils that contain friction modifiers while not for other gear oils, at all contact pressures investigated. In mixed lubrication region, temperature decreases friction at low contact pressures while increases friction at high contact pressures. The effect of slide–roll ratio on friction is significant in boundary lubrication region especially at higher temperature while less significant in mixed lubrication region at both low and high temperatures. The ranking of gear oils for friction in boundary and mixed lubrication regimes is similar both in rolling–sliding and pure sliding contacts, regardless of temperature. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
528.
General mortality analysis showed an increasing tendency of circulatory diseases in two villages examined. Respiratory diseases and suicide were more frequent in the village with greater pesticide use (village I). The relative risk (RR) of gastric cancer for men is significantly higher in village I (high rate of pesticide use) than in the county as a whole (RR, 1.65; 95% confidence interval (CI), 0.96-2.83) and also in relation to the national data (RR, 3.20; 95% CI, 1.91-5.36). Since the nitrate concentration in the drinking water, the drug consumption, smoking and eating habits are similar in the two villages, and since alcohol consumption is higher in village II (moderate rate of pesticide use), it seems that nitrosable pesticides may play a role in the etiology of stomach cancer. This is supported by the fact that a higher number of gastric cancer cases was found where larger quantities of nitrosable pesticides had been used.  相似文献   
529.
The dose responses of the most commonly used high potency sweeteners (HPSs) have been measured by a more precise sensory procedure. The data were analyzed by Black's pharmacological model that takes into account not only agonist binding affinity but transduction efficiency as well. HPSs are clearly segregated into 2 groups depending on whether they bind to T1R2 or T1R3 of the receptor heterodimer. Surprisingly, the more potent sweeteners have lower transduction efficiencies. The implications of these on consumer product development and HPS design are discussed.  相似文献   
530.
Chemically synthesized nanocrystal quantum dots (NQDs) are promising materials for applications in solution‐processable optoelectronic devices such as light emitting diodes, photodetectors, and solar cells. Here, we fabricate and study two types of p‐n junction photodiodes in which the photoactive p‐layer is made from PbS NQDs while the transparent n‐layer is fabricated from wide bandgap oxides (ZnO or TiO2). By using a p–n junction architecture we are able to significantly reduce the dark current compared to earlier Schottky junction devices without reducing external quantum efficiency (EQE), which reaches values of up to ~80%. The use of this device architecture also allows us to significantly reduce noise and obtain high detectivity (>1012 cm Hz1/2 W?1) extending to the near infrared past 1 μm. We observe that the spectral shape of the photoresponse exhibits a significant dependence on applied bias, and specifically, the EQE sharply increases around 500–600 nm at reverse biases greater than 1 V. We attribute this behavior to a “turn‐on” of an additional contribution to the photocurrent due to electrons excited to the conduction band from the occupied mid‐gap states.  相似文献   
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