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51.
An algorithm using no external data is proposed for removing the inhomogeneous effect of thin cloudiness and other aerosols on multispectral satellite sensor images such as Landsat Enhanced Thematic Mapper (ETM) images. The method consists of a series of digital processing operations and is based on principal component analysis (PCA). The goal is to generate, for every original band, a new band whose digital number (DN) values are related only to the atmospheric intensity effect. An example is shown and some limitations are discussed.  相似文献   
52.
The stabilizing effect of microgroove surface morphology on viscous drag reduction was studied experimentally in the inlet region of a plane channel flow. The stabilization is thought to be due to the ability of a microgrooved surface pattern to suppress the velocity fluctuations in the spanwise direction on a restricted portion of the wetted surface, which prevents vorticity development at the wall and consequently across the entire flow field. This smart microflow control strategy, which works successfully only under very particular circumstances, was implemented in a microgroove-modified channel flow in which the front part has a microgrooved surface topology. The results of pressure drop measurements indicate that microgrooved surfaces can effectively stabilize laminar boundary layer development, leading to a significant reduction in the viscous drag. In the rear flat part of the microgroove-modified channel test section, a maximum drag reduction of DR @ 35%{\rm DR\simeq 35\%} was measured. This corresponds to an overall drag reduction of DR @ 16%{\rm DR\simeq 16\%} at a length Reynolds number of Rex @ 106.Re_x\simeq 10^6. The drag reduction effect persisted in a narrow range of flow velocities and for the reported experimental conditions corresponds to microgroove dimensions between 1.5 and 2.5 viscous length-scales.  相似文献   
53.
This paper investigates the propagation of thickness disturbances on the free surface of a thin viscous liquid film on a solid substrate. On the free surface of the film the disturbances are induced by moving local external pressure perturbations acting on the surface. The analysis is performed by the Fourier‐Laplace transform applied to the linearized perturbation equations for small amplitudes. The amplitude of the interface deflection caused by the disturbance, is reconstructed by the inverse Fourier‐Laplace transform and numerically evaluated in the long time limit in long wave approximation. The proposed technique appears promising for probing the slip length of a thin film by recording its free surface response to a moving perturbation.  相似文献   
54.
The neuropeptides vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) down-regulate cytokine production. Because human septic shock involves excessive cytokine production, the effect of VIP/PACAP was investigated in a high endotoxemia murine model. Both peptides protect against endotoxin-induced lethality and prevent septic shock-associated histopathological alterations. VIP/PACAP reduce serum and peritoneal TNF-alpha and IL-6, suggesting that the protective effect is exerted by inhibiting the production of endogenous TNF-alpha/IL-6. Consistent with this mechanism, VIP does not protect against septic shock induced by exogenous TNF-alpha. The immunomodulatory role of VIP in vivo is supported by the appearance of high levels of VIP in serum and peritoneal fluid following LPS administration. Thus, the neuropeptides VIP/PACAP protect from the lethal effect of high endotoxemia, presumably by down-regulating TNF-alpha and IL-6 production, and may offer an alternative in the treatment of human septic shock syndrome.  相似文献   
55.
In this work, the different computational paradigms used in Artificial Intelligence (AI) and Autonomous Robotics are revised in the context of the reactive and situated paradigm. In particular, a Neural Computational paradigm based on perceptual association maps is revised. We explore the Singer hypothesis about the evidence of the same neural mechanism known from retinotopic projections. Finally, the implications of this computational paradigm with maps in the context of the definition, design, building and evaluation of neuroprosthesis are discussed.  相似文献   
56.
This paper presents a study on the application of granite fines (GF) originating from the granite industry in the Northwest of Spain for the construction of embankment fills. A numerical solver was developed to simulate the unsaturated consolidation of a compacted earthfill (water content close to saturation), introducing the effect of secondary compression, and reproducing the construction process to be followed. The results obtained are quite encouraging, since settlements were found to be within an acceptable range. Nevertheless, the results also showed the need to improve the experimental characterization of the “in-situ” preconsolidation of the GF before using them in real applications.  相似文献   
57.
Open DRM and the Future of Media   总被引:1,自引:0,他引:1  
This article offers an analysis of the various methods for implementing interoperable digital rights management platforms.  相似文献   
58.
In a routine procedure for collecting human skin spectra using fiber optic diffuse reflectance spectroscopy, the fiber optic probe is put gently in contact with the skin surface. The purpose of this work is to investigate the influence of probe pressure on in-vivo diffuse reflectance spectroscopy measurements performed by a non-trained operator. In addition, we include simulation using diffusion theory that explains the behavior of diffuse reflectance spectra with the increase of probe pressure. The article is published in the original.  相似文献   
59.
Model oil-in-water emulsions containing epicatechin (EC) and epigallocatechin gallate (EGCG) showed a synergistic increase in stability in emulsions containing added albumin. EGCG showed a stronger synergy (35%) with ovalbumin than did EC. Oxidation of the oil was monitored by determining peroxide values and hexanal contents. The effect of bovine serum albumin (BSA) on model oil-in-water emulsions containing each of the green tea catechins [epicatechin gallate (ECG), EGCG, EC and epigallocatechin (EGC)] was studied during storage at 30 °C. The green tea catechins showed moderate antioxidant activity in the emulsions with the order of activity being ECG ≈ EGCG > EC > EGC. Although BSA had very little antioxidant activity in the absence of phenolic antioxidants, the combination of BSA with each of the catechins showed strong antioxidant activity. BSA, in combination with EC, EGCG or EGC, showing the strongest antioxidant activity with good stability after 45 days storage. Model experiments with the catechins stored with BSA in aqueous solutions confirmed that protein–catechin adducts with antioxidant activity were formed between the catechins and protein. The antioxidant activity of the separated protein–catechin adducts increased strongly with storage time and was stronger for EGCG and ECG than for EC or EGC.  相似文献   
60.
When rotating stripes or other periodic stimuli cross the retina at a critical rate, a reversal in the direction of motion of the stimuli is often seen. This illusion of motion perception was used to explore the roles of retinal and perceived motion in the generation of optokinetic nystagmus. Here we show that optokinetic nystagmus is disrupted during the perception of this illusion. Thus, when perceived and actual motion are in conflict, subjects fail to track the veridical movement. This observation suggests that the perception of motion can directly influence optokinetic nystagmus, even in the presence of a moving retinal image. A conflict in the neural representation of motion in different brain areas may explain these findings.  相似文献   
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