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991.
Previously it was proposed that the solvent power of a pure or mixed organic liquid for a given polymer can be characterized by two parameters δh and χH. Using these two parameters, a two-dimensional (2D) solubility diagram can be constructed to predict solubility or insolubility. In the investigation only the polymers, poly(methyl methacrylate), polystyrene, and poly(vinyl acetate), were used to demonstrate the applicability of the 2D method. In this note, applicability of the 2D method to the 33 polymers investigated in Hansen's works is presented. 相似文献
992.
High-performance, reliable, and robust products with a short development schedule are general design aims. FACE was developed to achieve these goals, including the organization of a design flow, a frequency-driven information analyzer, compiler techniques (code generator and instruction optimization), and a hierarchical object design library. This paper explores the design space of a retargetable compiler and a reconfigurable hardware, which combine both software and hardware reprogrammability. The environment, FACE, we have developed allows us to quickly move the functions between software and hardware in a state of flux. Finally, it generates the application specific integrated processor (ASIP) and a compiler for the new ASIP architecture. The case study is considered which demonstrates the efficiency in ASIP design of FACE. 相似文献
993.
我国炼油厂大型化的探讨 总被引:1,自引:0,他引:1
赖周平 《石油化工设备技术》1996,17(6):1-4
简要介绍了国外炼油厂大型化的情况,指出了大型化的优缺点;着重就我国炼油厂大型化的现状、目标、措施和途径进行了分析和论述。 相似文献
994.
The coupled bridge foundation-superstructure finite-element code FLPIER was employed to predict the lateral response of the single piles and 3 × 3 to 7 × 3 pile groups founded in both loose and medium dense sands. The p-multiplier factors suggested by McVay et al. for laterally loaded pile groups with multiple pile rows were implemented for the predictions. The soil parameters were obtained through a back-analysis procedure based on single pile test results. The latter, as well as the numerical predictions of both the single and group tests, are presented. It was found that the numerical code FLPIER did an excellent job of predicting the response of both the single piles and the 3 × 3 to 7 × 3 pile groups. The latter involved the predictions of lateral load versus lateral deflection of the group, the shears and bending moments developed in the individual piles, and the distributions of the lateral loads in each pile row, which were all in good agreement with the measured results. 相似文献
995.
Monoclonal antibodies which recognize antigenic determinants expressed by T-cells and Ig-bearing cells, respectively, allowed lymphocyte subpopulations involved in allograft rejection of muscle transplants to be identified in the teleost fish Dicentrarchus labrax (L.). The monoclonal antibody DLT15 first allowed recognizing T-cells involved in an in vivo antigen-driven cellular response in teleosts. Immunohistochemical studies showed a high density of lymphocytes in allografts and provided evidence of predominance of T-cells. The heterogeneity of the cell populations recognized by the antibodies was evidenced by the different size, cytology, and staining patterns of T-cells and Ig-bearing cells. 相似文献
996.
Huang-Chung Cheng Wen-Koi Lai Chuan-Chou Hwang Miin-Horng Juang Shu-Ching Chu Tzeng-Feng Liu 《Electron Device Letters, IEEE》1999,20(10):535-537
Nitridation of stacked poly-Si gates by inductively coupled N2 plasma (ICNP) treatment has been shown to suppress boron penetration and improve gate oxide integrity. The ICNP treatments on the stacked poly-Si layers create nitrogen-rich layers not only between the stacked poly-Si layers but also in the gate oxide after post implant anneal, thus resulting in effective retardation of boron diffusion. In addition, positioning of ICNP treatment closer to gate oxides leads to higher nitrogen peaks in the gate oxide region, resulting in further suppression of boron penetration and improvement of gate oxide reliability 相似文献
997.
Wen-Chen Huang Cheng Chung Hsu Chungnan Lee Ping-Hong Lai 《IEEE engineering in medicine and biology magazine》1999,18(4):100-105
The purpose of this research is to detect and enhance the recurrent nasal tumor region by computing the relative intensity difference between consecutive MR images after using a contrast agent. In this article, we apply a relative signal increase model to recognize a recurrent nasal tumor by dynamic MR images. A robust estimation technique is used to deal with matching corresponding points among different images. The active contour technique is applied to refine automatically the region of interest and obtain a more precise definition of the area of interest. The quantitative evaluation of dynamic MR data is modeled by fitting three-parameter time-intensity curves 相似文献
998.
This paper presents a new decomposition method, based on the Lagrangian relaxation technique, for solving the unit commitment problem with ramp rate constraints. By introducing an additional vector of multipliers to represent the cost of “system ramping demand”, this method can handle the coupling constraints between time periods while still keeping the simplicity of the original decomposition method. A new algorithm for updating multipliers is also proposed. Similar to the bundle algorithm, this algorithm maintains the previous iteration history to approximate the dual envelope. Unlike the bundle algorithm, this new algorithm generates an update step along the subgradient direction without any quadratic programming (QP) code. The new algorithm combines the bundle algorithm's smooth approach to the dual optimum with the sub-gradient method's fast update 相似文献
999.
Jih-Sheng Lai Byeng-Mun Song Rui Zhou Hefner A. Jr. Berning D.W. Chih-Chieh Shen 《Industry Applications, IEEE Transactions on》2001,37(5):1282-1289
A new class of MOS-gated power semiconductor devices Cool MOS (Cool MOS is a trademark of Infineon Technologies, Germany) has been introduced with a supreme conducting characteristic that overcomes the high on-state resistance limitations of high-voltage power MOSFETs. From the application point of view, a very frequently asked question immediately arises: does this device behave like a MOSFET or an insulated gate bipolar transistor (IGBT)? The goal of this paper is to compare and contrast the major similarities and differences between this device and the traditional MOSFET and IGBT. In this paper, the new device is fully characterized for its: (1) conduction characteristics; (2) switching voltage, current, and energy characteristics; (3) gate drive resistance effects; (4) output capacitance; and (5) reverse-bias safe operating areas. Experimental results indicate that the conduction characteristics of the new device are similar to the MOSFET but with much smaller on-resistance for the same chip and package size. The switching characteristics of the Cool MOS are also similar to the MOSFET in that they have fast switching speeds and do not have a current tail at turn-off. However, the effect of the gate drive resistance on the turn-off voltage rate of rise (dv/dt) is more like an IGBT. In other words, a very large gate drive resistance is required to have a significant change on dv/dt, resulting in a large turn-off delay. Overall, the device was found to behave more like a power MOSFET than like an IGBT 相似文献
1000.