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21.
Kimura S. Maio K. Doi T. Shimano T. Maeda T. 《Electron Devices, IEEE Transactions on》2002,49(6):997-1004
We made photodetectors on a silicon-on-insulator (SOI) substrate by a 0.35-μm BiCMOS fabrication process to detect the signal light used in an optical disk system. Investigating their characteristics at two wavelengths, 410 and 780 nm, for different structures, we found that the thickness of the silicon crystalline layer on the insulator strongly affected the frequency response at the longer wavelength, while the cutoff frequency was over 500 MHz for the shorter wavelength. We also simulated the frequency response 相似文献
22.
We investigated the relationship between thermal stability of NiSi films and the implanted dopant species on Si substrates. The most stable NiSi layer appeared on Boron-implanted Si substrate, where the formation of pseudo-epitaxial transrotational structure was observed, just in case that the dose of boron is more than 5e15 atoms/cm2. This unique crystallographic orientation of NiSi film on Boron-implanted substrate is a key role of thermal stability because thermal stress at grain boundary can be diminished by peculiar arrangement of transrotational domains, owing to the anisotropy in coefficient of thermal expansion (CTE) of NiSi. 相似文献
23.
One possible origin of the loss increase phenomenon with heat treatment at 200°C (H2 evolution from the coating material) has been investigated, using optical fibre coated with silicone resin containing the Si?D group. Although OH absorption at 1.4 ?m increases with 200°C heat treatment, no OD peak is observed. It is suggested that silicone resin containing no Si?H and Si?CH2?CH2?Si groups is appropriate as a coating material as no H2 evolution is present. 相似文献
24.
A light modulator using piezoelectric films based on optical interference of the Mach-Zehnder type has been proposed and demonstrated. The modulator is constructed with two optical waveguides joined to each other at both ends to divide the incident light and to recombine them, and each waveguide is fabricated on a polyvinylidene fluoride (PVDF) film to serve as a voltage-driven phase-shifter. 相似文献
25.
Kawahara T. Horiguchi M. Etoh J. Sekiguchi T. Kimura K. Aoki M. 《Solid-State Circuits, IEEE Journal of》1995,30(9):1030-1034
A low-power dynamic termination scheme is proposed and demonstrated as a way to reduce power dissipation for high-speed data transport. In this scheme, the transmission lines are terminated only if the signals change. The gate of a switching MOS transistor connected to a termination resistor is driven by differentiating the transmission signal with a resistor and a capacitor. The power dissipation of the terminating resistor can be reduced to 1/5 in the conventional determination scheme, and overshoot can be reduced to 1/5 that in the open scheme. This scheme is promising for use with palm-top equipment, facilitating high-speed low power operation 相似文献
26.
Sakamoto K. Kasahara Y. Kimura I. 《Geoscience and Remote Sensing, IEEE Transactions on》1995,33(3):528-534
A straightforward method for determination of k-vector (wave normal) direction of a whistler mode signal observed onboard spacecraft consists in measuring three components of the wave magnetic field with their instantaneous amplitudes and phases. In that method, one needs to send by telemetry a total wave form of a signal, which requires much larger bandwidth than for sending amplitudes only. The present study develops another method of determination of the wave normal direction based only on the amplitude data; the method is checked using Omega signal observations by the Akebono satellite. It should, however, be noted that the sense of k-vector is not determined by this proposed method 相似文献
27.
Here we show a technique to obtain a tilt series of dark-field (DF) transmission electron microscopy (TEM) images in ordering alloys for tomographic three-dimensional (3D) observations. A tilt series of DF TEM images of D1a-ordered Ni4Mo precipitates in a Ni-Mo alloy was successfully obtained by adjusting a diffraction condition for a superlattice reflection from the Ni4Mo precipitates. Since the superlattice reflection usually has a long extinction distance, dynamic diffraction effects such as thickness fringes can be suppressed to some extent with precise realignment of the diffraction condition. By using the tilt series of the DF TEM images, we attempted a computed TEM tomography to visualize 3D shapes and positions of the precipitates. 相似文献
28.
Wenyao Li Bingjie Zhang Runjia Lin SocMan Ho‐Kimura Guanjie He Xiying Zhou Junqing Hu Ivan P. Parkin 《Advanced functional materials》2018,28(23)
A uniform dendritic NiCo2S4@NiCo2S4 hierarchical nanostructure of width ≈100 nm is successfully designed and synthesized. From kinetic analysis of the electrochemical reactions, those electrodes function in rechargeable alkaline batteries (RABs). The dendritic structure exhibited by the electrodes has a high discharge‐specific capacity of 4.43 mAh cm?2 at a high current density of 240 mA cm?2 with a good rate capability of 70.1% after increasing the current densities from 40 to 240 mA cm?2. At low scan rate of 0.5 mV s?1 in cyclic voltammetry test, the semidiffusion controlled electrochemical reaction contributes ≈92% of the total capacity, this value decreases to ≈43% at a high scan rate of 20 mV s?1. These results enable a detailed analysis of the reaction mechanism for RABs and suggest design concepts for new electrode materials. 相似文献
29.
Yuji Teramoto Tatsuro Ueki Katsuji Kimura Seinosuke Ueda Shigeomi Shiota 《Journal of the Institute of Brewing》1993,99(2):139-142
An effective utilization system using distillery waste discharged from Japanese traditional shochu factory was developed. Mugi (barley) shochu distillery waste discharged from a novel vacuum distillation procedure (35–40°C) contained a large number of viable yeast (7 × 106 cells/ml), glucoamylase activity (19.7 units/ml), acid protease activity (940 units/ml), and neutral protease activity (420 units/ml). Ethanol fermentation was achieved with a mash composed of glucose as the sola carbon source and mugi shochu distillery waste. After ethanol fermentation was completed the fermented broth was again distilled at 35–40°C in vacuo and the non volatile residue used in the next ethanol fermentation. In this way, semicontinuous ethanol fermentation system of more than 10 cycles was developed. Even in the distillate of the mash of the 8th fermentation cycle, 7.9% of ethanol, 33.0 ppm of ethyl acetate, 28.5 ppm of isobutyl alcohol, and other aromatic compounds were present. A semicontinuous ethanol fermentation system has been developed for shochu distillery waste which conventionally is treated as wastewater. 相似文献
30.
M. Takemi T. Kimura T. Miura K. Goto Y. Mihashi S. Takamiya 《Journal of Electronic Materials》1996,25(3):369-374
A comparative study has been carried out regarding selective embedding growth of InP by metalorganic chemical vapor deposition
(MOCVD) around dry-etched mesas, using two types of reactors: a conventional horizontal type and a highspeed rotating-susceptor
type. In the case of the conventional horizontal-type MOCVD, overgrowth on the mask was observed when the growth temperature
was low (600°C). On the other hand, an almost planar grown surface without such overgrowth was achieved by using the high-speed
rotating-susceptor MOCVD for a wide range of growth temperatures, especially even at a low growth temperature of 580°C. Regarding
the high-speed rotating-susceptor MOCVD, we have also investigated the effects of dopants on the growth behaviors and have
found a remarkable difference between n-type S-doped and p-type Zn-doped InP in the growth behaviors. The mechanism for suppressing
overgrowth in case of the high-speed rotating-susceptor MOCVD, as well as the cause for the different effects between the
dopants, are discussed. 相似文献