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71.
Distortion-product otoacoustic emissions (DPOAEs) have been shown to be ideally sensitive to interruptions of the cochlear blood flow. However, a 15- to 30-second latency typically occurs between cessation of circulation and measurable DPOAE level changes. DPOAEs can also be characterized by phase measures. The aim of the present study was to determine in 10 rabbits the effects on DPOAE phase of repetitively compressing the internal auditory artery. In contrast to the delays measured by DPOAE level, phase changes were detected 1 to 5 seconds after internal auditory artery compression. These data suggest that the essentially "real time" monitoring of cochlear function with DPOAE phase can be used to ensure hearing preservation during surgery involving the porus acousticus and skull base.  相似文献   
72.
BACKGROUND: This article presents results of the acute treatment phase of a 2-site study comparing cognitive behavioral group therapy (CBGT) and treatment with the monoamine oxidase inhibitor phenelzine sulfate for social phobia. METHODS: One hundred thirty-three patients from 2 sites received 12 weeks of CBGT, phenelzine therapy, pill placebo administration, or educational-supportive group therapy (an attention-placebo treatment of equal credibility to CBGT). The "allegiance effect," ie, the tendency for treatments to seem most efficacious in settings of similar theoretical orientation and less efficacious in theoretically divergent settings, was also examined by comparing responses to the treatment conditions at both sites: 1 known for pharmacological treatment of anxiety disorders and the other for cognitive behavioral treatment. RESULTs: After 12 weeks, phenelzine therapy and CBGT led to superior response rates and greater change on dimensional measures than did either control condition. However, response to phenelzine therapy was more evident after 6 weeks, and phenelzine therapy was also superior to CBGT after 12 weeks on some measures. There were few differences between sites, suggesting that these treatments can be efficacious at facilities with differing theoretical allegiances. CONCLUSIONS: After 12 weeks, both phenelzine therapy and CBGT were associated with marked positive response. Although phenelzine therapy was superior to CBGT on some measures, both were more efficacious than the control conditions. More extended cognitive behavioral treatment and the combination of modalities may enhance treatment effect.  相似文献   
73.
Yamamoto H  Uenoyama H  Hirai K  Dou X  Ozaki Y 《Applied optics》1998,37(13):2640-2645
We describe the quantitative analysis of some metabolic gases bymultichannel Raman spectroscopy. Raman spectra were measured forair, acetone, ammonia, carbon dioxide, and mixed gas consisting ofacetone, ammonia, and air. We designed a new elliptic-sphericalintegration type of cell holder to obtain the Raman spectra of gaseswith a high signal-to-noise ratio. Concentrations of acetone, ammonia, and carbon dioxide were determined by the peak intensities ofRaman bands at 2940, 3228, and 1385 cm(-1), respectively. To compensate for the fluctuations of Ramanintensities caused by several factors, such as the fluctuations oflaser power, the peak intensity of a band at 2324 cm(-1) dueto nitrogen gas was used as an internal intensity standard. Thecorrelation coefficient between the corrected Raman intensity at 2940cm(-1) and the concentration of acetone was calculated to be0.984 for a concentration range of 2-12 ppm. The detection limitof acetone gas was found to be 2 ppm.  相似文献   
74.
We measured the interfacial tension of 3 He-4 He mixtures under pressure of 21 atm down to about 0.2K by using the resonance of the interfacial wave and found that the decrease from absolute zero is proportional to T2 up to about 0.4 K. From the simple extrapolation of this T2-dependence the interfacial tension at absolute zero is obtained as i (0) = 19.3 ± 1.3 mdyne/cm. Compared with saturated vapor pressure, the interfacial tension at absolute zero decreases by about 20%, and the coefficient of the T2-dependence does not depend strongly on pressure. The large T2-dependence both at saturated vapor pressure and at 21 atm may be attributable to the change in density difference between the two phases.  相似文献   
75.
This paper presents a novel method to predict the starting performance of synchronous motors. This proposed strategy is based on a simple standstill response testing method using a small-capacity DC power supply unit, tentatively named the DC decay testing method in this paper, and can be applied to standstill synchronous motors with the rotor in any arbitrary position. The proposed testing method is carried out on a 10 kW, 200 V, 31.9 A, 50 Hz four-pole laminated salient-pole synchronous motor with damper windings. The results measured by on-load test and those predicted by the proposed method on starting performance clearly show the validity of the proposed method  相似文献   
76.
We propose an explanatory mechanism for multilayered neural networks (NN). In spite of the effective learning capability as a uniform function approximator, the multilayered NN suffers from unreadability, i.e., it is difficult for the user to interpret or understand the "knowledge" that the NN has by looking at the connection weights and thresholds obtained by backpropagation (BP). This unreadability comes from the distributed nature of the knowledge representation in the NN. In this paper, we propose a method that reorganizes the distributed knowledge in the NN to extract approximate classification rules. Our rule extraction method is based on the analysis of the function that the NN has learned, rather than on the direct interpretation of connection weights as correlation information. More specifically, our method divides the input space into "monotonic regions" where a monotonic region is a set of input patterns that belongs to the same class with the same sensitivity pattern. Approximate classification rules are generated by projecting these monotonic regions.  相似文献   
77.
The tangential momentum accommodation coefficient (TMAC) was investigated experimentally from the mass flow rate through a single microtube under the slip flow and the early part of the transition regime. The measurements were carried out by the constant-volume method under the mean Knudsen number smaller than 0.3, which is based on the mean pressure of the inlet and the outlet of the microtube, to apply the second-order slip boundary condition. To measure TMACs on various materials, quite large microtube was employed, which require the reduction in leakage. TMAC was obtained from the slip coefficient determined by the relation of the mass flow rate to the mean Knudsen number. The obtained mass flow rate was well explained by the theoretical equation. TMACs of deactivated-fused silica with argon, nitrogen, and oxygen were measured, showing the tangential momentum was not accommodated completely to the surface, and the values showed good agreement with previous studies. From the comparison between microtubes with different inner diameter, it is showed that TMAC is determined mainly by gas species and surface material.  相似文献   
78.
79.
A neuro-controller for vibration control of load in a rotary crane system is proposed involving the rotation about the vertical axis only. As in a nonholonomic system, the vibration control method using a static continuous state feedback cannot stabilize the load swing. It is necessary to design a time-varying feedback controller or a discontinuous feedback controller. We propose a simple three-layered neural network as a controller (NC) with genetic algorithm-based (GA-based) training in order to control load swing suppression for the rotary crane system. The NC is trained by a real-coded GA, which substantially simplifies the design of the controller. It appeared that a control scheme with performance comparable to conventional methods can be obtained by a relatively simple approach. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
80.
DNA machines consisting of consecutive hairpins, which we have previously described, have various potential applications in DNA computation. In the present study, a 288-base DNA machine containing four consecutive hairpins was successfully constructed by ligation and PCR. PAGE and fluorescence spectroscopy experiments verified that all four hairpins were successfully opened by four opener oligomers, and that hairpin opening was dependent on the proper openers added in the correct order. Quantitative analysis of the final results by fluorescence spectroscopy indicated that all four hairpins were open in about 1/4 to 1/3 of the DNA machines.  相似文献   
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