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11.
Vittorio Ghergia 《Sadhana》1992,17(3-4):411-430
Starting from the present state-of-the-art of discrete devices up to the realization of monolithic semiconductor integrated
prototypes, an overview of optoelectronic devices for telecommunications is given. Among discrete devices single frequency
lasers, tunable and multi-sectionDFB lasers andPIN andAPD photodiode detectors are analysed, including the use of new technologies in progress for a second generation of devices.
On the future perspective ofIBCN distribution networks, some economics of the hybrid and monolithic form of integration are attempted. Finally a short outline
of the most recent achievements in monolithic integration is presented, taking into particular consideration the activities
in this field byEEC ESPRIT andRACE programmes. 相似文献
12.
T. D. M. Weijers H. Timmers R. G. Elliman 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):397-401
The impact of the pulse height deficit effect in gas ionization detectors on the accurate extraction of depth information from heavy ion elastic recoil detection spectra has been investigated. Thin GaN films and GexSi1−x/Si heterostructures have been analyzed with a 200 MeV 197Au beam. Employing an empirical parameterisation of the pulse height deficit, a global energy calibration of the detector can be achieved. Energy spectra have been compared, calibrated with either a constant or a full energy-dependent compensation for the deficit. A constant compensation results in significant distortion of the extracted depth profile for heavier ions, whereas an energy-dependent compensation yields true concentration–depth profiles. 相似文献
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利用线阵CCD实现宽波段、大视场短脉冲激光波长的远场测量 总被引:5,自引:1,他引:4
介绍了一种利用线阵CCD实现宽波段、大视场脉冲激光波长及方向远场测量的原理和实验装置;对强烈背景下激光信号的提取与处理方法进行了理论分析和实验研究,给出了系统信噪比与探测器件工作频率的理论公式;最后简要介绍了远场实验和测试结果 相似文献
16.
F. Nava G. Wagner C. Lanzieri P. Vanni E. Vittone 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2003,510(3):273-280
The development of SiC minimum ionising particle (MIP) detectors imposes severe constrains in the electronic quality and the thickness of the material due to the relatively high value of the energy required to produce an electron–hole pair in this material by MIP against the value for Si. In this work, particle detectors were made using semiconductor epitaxial undoped n-type 4H-SiC as the detection medium. The thickness of the epilayer is on the order of 40 μm and the detectors are realised by the formation of a nickel silicide on the silicon surface of the epitaxial layer (Schottky contact) and of the ohmic contact on the back side of 4H-SiC substrate. The low doping concentration (6×1013 cm−3) of the epilayer allows the detector to be totally depleted at relatively low reverse voltages (100 V). We present experimental data on the charge collection properties by using 5.486 MeV -particles impinging on the Schottky contact. A 100% charge collection efficiency (CCE) is demonstrated for reverse voltages higher than the one needed to have a depletion region equal to the -particle extrapolated range in SiC. The diffusion contribution of the minority change carriers to CCE is pointed out. By comparing measured CCE values to the outcomes of drift–diffusion simulation, values are inferred for the hole lifetime within the neutral region of the charge carrier generation layer. 相似文献
17.
The ALCHEMI method for locating the sites of foreign atoms within crystals is known to be sensitive to the delocalized emission of X-rays. This can result in large errors in some cases through differences in delocalization for different excitations or by error amplification in the ratio method of analysis. An alternative approach to the analysis of ALCHEMI data, using multivariate statistical analysis, is extended to the case of multiple impurities. Initial results from zone-axis channelling experiments for a Yb-doped zirconolite (CaZrTi2O7) are shown to confirm the improved accuracy of this method, especially for axial orientations. Data were collected using a 400-keV analytical electron microscope fitted with an intrinsic Ge X-ray detector. The potential advantages for ALCHEMI analysis of Ge detectors are considered. 相似文献
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This work summarizes the progress in the study of the superconductor response to optical radiation and in the development of infrared detectors. The recent advances in the design of high-T
c superconducting radiation detectors using silicon microfabrication technology are emphasized. Thermal and optical properties important for the detector performance are discussed. The mechanism of the nonequilibrium optical response and its potential use to build fast and sensitive radiation detectors are described. Future challenges and opportunities in the development of high-T
c superconducting radiation detectors are highlighted. 相似文献
20.
K. Kosai 《Journal of Electronic Materials》1995,24(5):635-640
In this article, device modeling refers to numerical simulation of semiconductor device physics to predict electrical behavior.
The silicon integrated circuit industry provides the example for the use of technology computer-aided design to simulate wafer
fabrication processes, and the electrical performance of devices and circuits. This paper first reviews semiconductor device
modeling in general, then as applied in work supporting the development and analysis of HgCdTe infrared detectors. Example
applications of one- and two-dimensional device modeling are simulation of a bias-selectable, integrated two-color detector,
and two-dimensional effects on the spectral response of a HgCdTe detector with composition grading. 相似文献