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31.
Sudou M. Takao H. Sawada K. Ishida M. 《Components and Packaging Technologies, IEEE Transactions on》2007,30(3):457-463
This paper reports about a novel wafer-level integration technique of discrete surface mount devices (SMDs). It enables wafer-level mounting of plural kinds of SMDs on a silicon (Si)-wafer using vibration and gravity force. Deep holes with 400-m depth are formed on the surface of a Si-wafer by deep reactive ion etching process after general integrated circuit process for positioning of SMDs. A non-conductive adhesive (CYTOP) are coated on the deep holes and it is used to fix the aligned SMDs. SMDs are distributed on a Si-wafer mounted on vibration generator, and then a vibration is applied. The SMDs migrate due to the reduced friction between the wafer surface, and they drop into the holes on the silicon wafer. The size of the holes has an appropriate clearance to the size of SMD. In order to align two or more kinds of SMDs, sizes of the deep holes on a Si-wafer are adjusted to the size of each SMD. SMDs with the largest size are dropped into the holes first, and then the secondary large SMDs are dropped into the holes with the corresponding size. SMDs are finally connected electrically by wire bonding at the final step. In the experiment, two different sizes of SMD were successfully mounted into all the holes on a Si-wafer automatically. This technology will be a wafer-level process technology which is very promising to integrate two or more kinds of discrete elements. 相似文献
32.
Ohnuma I. Miyashita M. Xing Jun Liu Ohtani H. Ishida K. 《Electronics Packaging Manufacturing, IEEE Transactions on》2003,26(1):84-89
We have recently developed a thermodynamic database for micro-soldering alloys, alloy database for micro-solders (ADAMIS). ADAMIS which consists of the elements Ag, Bi, Cu, In, Pb, Sb, Sn, and Zn has been constructed by the calculation of phase diagrams (CALPHAD) method. The thermodynamic parameters for describing the Gibbs energy of the liquid and solid phases have been evaluated by optimizing the experimental data on phase boundaries and thermo-chemical properties. In this paper, the phase equilibria and the related thermodynamic properties pertaining to the Sn-Ag-X (X=Bi, In, Cu, and Zn) alloys are examined using ADAMIS. Typical examples of the isothermal and vertical section phase diagrams, liquidus surface, etc. for these promising lead-free solders are presented. In addition, ADAMIS is also applied to calculate the nonequilibrium solidification process using the Scheil model. 相似文献
33.
Solitary DFB laser diodes with 174 kHz beat linewidth are applied to a 10 Gbit/s optical BPSK homodyne detection system for the first time: a sensitivity of -38.9 dBm was achieved. A three-electrode laser forms the local oscillator and is modulated with a partial push-pull scheme to improve its frequency response 相似文献
34.
Masahiro Ishida Toru Nakura Takashi Kusaka Satoshi Komatsu Kunihiro Asada 《Journal of Electronic Testing》2016,32(3):257-271
This paper proposes a power integrity control technique for dynamically controlling power supply voltage fluctuations for a device under test (DUT), and demonstrates its effectiveness for eliminating the overkills/underkills due to the difference of power supply impedance between an automatic test equipment (ATE) and a practical operating environment of the DUT. The proposed method injects compensation currents into the power supply nodes on the ATE system in a feed-forward manner such that the ATE power supply waveform matches with the one on the customer’s operating environment of the DUT. A method for calculating the compensation current is also described. Experimental results show that the proposed method can emulate the power supply voltage waveform under a customer’s operating condition and eliminate 95 % of overkills/underkills in the maximum operating frequency testing with 105 real silicon devices. Limitations and applications of the proposed method are also discussed. 相似文献
35.
Hirohisa Ohtsuki Shigeo Kawaoka Shigeru Miyagawa Masaru Ishida Yutaka Fukui 《International Journal of Electronics》2013,100(3):323-331
This paper proposes novel grounded and floating high order series and parallel immittance simulators using operational transconductance amplifiers (OTAs) and operational amplifiers (OAs) with a finite gain–bandwidth (GB) product. They are composed of active devices (OTAs and OAs) and resistances, and are suitable for monolithic implementation in either CMOS or bipolar technologies. They also realize both positive and negative high order immittances. The circuit characteristics can be electronically tuned by adjusting the transconductances of OTAs and the GB products of OAs. Any transfer functions are realizable using the proposed simulators. Two examples are shown, together with simulation results. 相似文献
36.
An image processing technique using analogue MOS current-mode circuits is presented. This approach is of interest in smart image sensors based on three-dimensional (or multi-layered) VLSI structures. High-performance smart image sensors with high resolution can be realised because the number of transistors required for image processing in each pixel is greatly reduced.<> 相似文献
37.
Takeshi Terayama Susumu Nagata Yohei Tanaka Akihiko Momma Tohru Kato Masaru Kunii Atsushi Yamamoto 《Journal of Electronic Materials》2013,42(7):2306-2313
Solid oxide fuel cells (SOFCs) are being researched around the world. In Japan, a compact SOFC system with rated alternative current (AC) power of 700 W has become available on the market, since the base load electricity demand for a standard home is said to be less than 700 W AC. To improve the generating efficiency of SOFC systems in the 700-W class, we focused on thermoelectric generation (TEG) technology, since there are a lot of temperature gradients in the system. Analysis based on simulations indicated the possibility of introducing thermoelectric generation at the air preheater, steam generator, and exhaust outlet. Among these options, incorporating a TEG heat exchanger comprising multiple CoSb3/SiGe-based TEG modules into the air preheater had potential to produce additional output of 37.5 W and an improvement in generating efficiency from 46% to 48.5%. Furthermore, by introducing thermoelectric generation at the other two locations, an increase in maximum output of more than 50 W and generating efficiency of 50% can be anticipated. 相似文献
38.
This paper presents the silicon based on-chip antenna using a LC resonator. The proposed antenna consists of a stacked capacitor and a spiral inductor on silicon substrate. The spiral inductor structure without underpass was proposed for improvement the performance of the silicon based-antenna. The resonant frequency of the fabricated antenna was measured as 465 MHz. Its return loss was 23.4 dB at resonant frequency. The antenna has a gain of ?35.75 dBi due to small size and silicon substrate. However, the fabricated antenna has good performance in the near-field. 相似文献
39.
Ishida M. Hatori N. Otsubo K. Yamamoto T. Nakata Y. Ebe H. Sugawara M. Arakawa Y. 《Electronics letters》2007,43(4):219-221
Low-driving-current temperature-stable 10 Gbit/s direct modulation was achieved for optimised 200 mum-long short cavity 1.3 mum p-doped quantum dot lasers. Driving conditions were 25.2 mAp-p for the modulation current and 23.4 mA for the bias current through the whole temperature range from 20 to 90degC 相似文献
40.
The narrow-gap compound semiconductor PbTe has high Hall mobility. The Fermi surface at the L-point in the Brillouin zone
has large anisotropy. In this work, we measured thermomagnetic effects in PbTe thin films to confirm anisotropy of the Nernst
coefficient A
Ne and show Nernst mobility from the ratio of A
Ne and the Seebeck coefficient S: μ
Ne = A
Ne/S. Angular dependences of the Nernst voltage show that A
Ne is independent of the angle between the temperature gradient and the magnetic field, because of the high L-point symmetry.
The calculated Nernst mobility was compared with the Hall mobility. Because the former is smaller, the Mott equation cannot
explain the Seebeck coefficient at room temperature. 相似文献