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排序方式: 共有1908条查询结果,搜索用时 15 毫秒
141.
Yoichi Kumada Daisuke Kuroki Hidefumi Yasui Takuhito Ohse Michimasa Kishimoto 《Journal of Bioscience and Bioengineering》2010,109(6):583-587
In this study, we characterized polystyrene-binding peptides (PS-tags) that possess a specific binding affinity for hydrophilic polystyrene (phi-PS) plates. Both the FITC-labeled PS19-1 (RAFIASRRIKRP) and PS19-6 (RIIIRRIRR) peptides showed strong binding affinity for commercially available hydrophilic, but not hydrophobic, PS plates in the presence of the non-ionic surfactant Tween 20. The dissociation constants (Kd) of the PS19-1 and PS19-6 peptides for the hydrophilic PS-A plate were 169 and 86 nM, respectively, and the Kd of both peptides increased with the concentration of NaCl or urea. Based on adsorption yield and residual activity of glutathione S-transferase (GST) after fusion with the PS19-6 peptide or its variants, it was found that the basic amino acid in the PS-tags, i.e., Arg was essential for the strong binding affinity of PS-tags in both the peptide and peptide-fused protein forms The aliphatic amino acids in PS19-6 and PS19-6L, such as Ile or Leu, were also effective. Thus, a series of PS-tags that possess this unusual feature, especially the peptides PS19-6 (RIIIRRIRR) and PS19-6L (RLLLRRLRR), are potential candidate affinity peptide tags for site-specific immobilization of proteins onto hydrophilic PS plates, which show potential as solid supports for protein-based biochips. 相似文献
142.
Daisuke HirookaAuthor Vitae Koichi SuzumoriAuthor VitaeTakefumi KandaAuthor Vitae 《Sensors and actuators. A, Physical》2011,171(2):283-291
In this article, we report a new particle-excitation flow control valve. The purpose of this study is the development of a particle-excitation flow control valve that can precisely control pneumatic cylinders. We have reported this flow control valve principle. The valve, driven by a PZT vibrator, has a simple lightweight structure with large flow rate. We report the relationship between the orifice arrangement and flow rate characteristics of the valve. We have designed a new prototype for the purpose of high controllability. We have measured flow-rate characteristics and confirmed the conditions necessary for continuous adjustment of flow quantity. The control valve works successfully to realize a change in flow rate. 相似文献
143.
144.
Satoshi Azuma Hisanori Yamasaki Daisuke Itoh Takafumi Maruyama 《Electrical Engineering in Japan》2008,165(4):84-91
A newly proposed energy‐compensating active control is implemented to reduce the return current noise which is caused by inverter‐driven electric car systems. The energy‐compensating active control detects the energy charged at the filter capacitor, and reduces the energy and current of the noise frequency component by simple feedback loop incorporated with the conventional motor torque controller. No additional sensors or circuit arrangements are necessary; therefore, the return current can be attenuated effectively without any further cost. The return current with an inverter system is measured using a current probe and an FFT analyzer, and it is shown that the 25‐Hz noise current is reduced by up to 10 dB with the control. The results reveal that the low‐frequency return current noise can be attenuated with the simple control scheme, which would expectedly reduce the size of filter reactors and capacitors to meet the current limit level of the signaling system's track relays. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 84–91, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20615 相似文献
145.
Takai Y. Fujita M. Nagata K. Isa S. Nakazawa S. Hirobe A. Ohkubo H. Sakao M. Horiba S. Fukase T. Takaishi Y. Matsuo M. Komuro M. Uchida T. Sakoh T. Saino K. Uchiyama S. Takada Y. Sekine J. Nakanishi N. Oikawa T. Igeta M. Tanabe H. Miyamoto H. Hashimoto T. Yamaguchi H. Koyama K. Kobayashi Y. Okuda T. 《Solid-State Circuits, IEEE Journal of》2000,35(2):149-162
This paper describes three circuit technologies indispensable for high-bandwidth multibank DRAM's. (1) A clock generator based on a bidirectional delay (BDD) eliminates the output skew. The BDD measures the cycle time as the quantity charged or discharged of an analog quantity, and replicates it in the next cycle. This achieves a 0.18-mm 2, two-cycle-lock clock generator operating from 25 to 167 MHz with a 30-ps resolution. (2) A quad-coupled receiver eliminates the internal skew caused by the difference between a rise input and a fall input by 40%. (3) An interbank shared redundancy scheme (ISR) with a variable unit redundancy (VUR) efficiently increases yield in multibank DRAM's. The ISR allows redundancy match circuits to be shared with two or more banks. The VUR allows the number of units replaced to be variable. These circuit technologies achieved a 250-Mb/s/pin, 8-bank, 1-Gb double-data-rate synchronous DRAM 相似文献
146.
Tomoyuki Kawase Kazuhiro Okuda Hiroyuki Kogami Hitoshi Nakayama Masaki Nagata Hiromasa Yoshie 《Journal of materials science. Materials in medicine》2010,21(2):731-739
Our animal implantation studies have demonstrated that, after osteogenic processing, cultured human periosteal sheets form
osteoid tissue ectopically without the aid of conventional scaffolding materials. To improve the osteogenic activity of these
periosteal sheets, we have tested the effects of including a scaffold made of salmon collagen-coated ePTFE mesh. Periosteal
sheets were produced with minimal manipulation without enzymatic digestion. Outgrown cells penetrated into the coated mesh
fiber networks to form complex multicellular layers and increased expression of alkaline phosphatase activity in response
to the osteoinduction. In vitro mineralization was notably enhanced in the original tissue segment regions, but numerous micro-mineral
deposits were also formed on the coated-fiber networks. When implanted subcutaneously into nude mice, periosteal sheets efficiently
form osteoid around the mineral deposits. These findings suggest that the intricate three-dimensional mesh composed of collagen-coated
fibers substantially augmented the osteogenic activity of human periosteal sheets both in vitro and in vivo. 相似文献
147.
An experimental evaluation of spatial distribution for deeply penetrating protons in carbon material
Mitsuo Tosaki Daisuke Ohsawa Yasuhito Isozumi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):59-62
The peak profile of the 4.8-MeV resonance by the 12C(p,p)12C reaction in backscattering geometry has been analyzed to examine two kinds of stragglings of proton, i.e. the depth straggling in the incoming path and the energy loss straggling in the outgoing path. The analysis, which is combined with existing theoretical treatments for the stopping process and the energy loss straggling, has made it possible to deduce the penetration depth and its spread at the resonance position in carbon materials. The present method, as a new tool for direct inspection of ion beams inside target material, is explained in detail. 相似文献
148.
A GaAs/AlGaAs directional coupler switch, for the first time with a device length shorter than 1 mm, has been fabricated by utilising the good controllability of molecular beam epitaxy and reactive ion beam etching. The switching voltage is as low as 5V. The extinction ratio is 17dB for a crossover state and 14dB for a straight-through state. 相似文献
149.
Kazuhiro Nagata Katsumi Ohira Hisao Yamada Kazuhiro S. Goto 《Metallurgical and Materials Transactions B》1987,18(3):549-555
The velocity and absorption coefficient of longitudinal ultrasonic waves with 5 and 10 MHz in molten and glassy silicates
and borates have been measured by means of the pulse-echo method in 300 to 1600 K. The silicate and borate were Na2O−SiO2, K2O−SiO2, PbO−SiO2, Na2O−B2O3, and PbO−B2O3. The velocity of sound decreased with increasing temperature and decreased rapidly near the transition temperature of glasses.
The product of the one-third power of velocity of sound and the molar volume of the oxide melt was constant and independent
of temperature. The absorption coefficient of ultrasonic waves in the oxide melts increased with an increase in viscosity.
The absorption mechanisms of ultrasonic waves and the mean free path of phonons in the oxide melts were discussed. 相似文献
150.
T. Hamada R. Morimo A. Takada Y. Yamashita K. Nakayama K. Nagata T. Yuji 《Journal of Materials Processing Technology》2000,100(1-3)
An experimental study has been carried out to investigate the synergistic effect of Ba4CuPt2O9 compounds on the critical current density of fluorine-doped YBCO superconductors. The Ba4CuPt2O9 compounds were synthesized by a solid state reaction. It was found that the synthesis temperature of the Ba4CuPt2O9 compounds was over 800°C, which was higher than that ever reported previously. In addition, the influence of Ba4CuPt2O9 compounds on the critical current density of YBCO superconductors has been investigated using two types of Ba4CuPt2O9 compounds: one is not heat-treated, i.e. source materials; and the other is heat-treated at 950°C. It was found that the former affected the orientation of the c-axes, but the latter did not have an influence on the orientation of the c-axes, but adversely affected the superconductivity of samples quenched at temperatures above 850°C. 相似文献