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排序方式: 共有876条查询结果,搜索用时 15 毫秒
61.
A Kawakami K Eguchi N Matsuoka M Tsuboi Y Kawabe T Aoyagi S Nagataki 《Canadian Metallurgical Quarterly》1996,39(8):1267-1276
OBJECTIVE: To investigate the mitogenic and anti-apoptotic effects of transforming growth factor beta 1 (TGF beta 1) on rheumatoid synovial cells in vitro. METHODS: Synovial cells were cultured with or without TGF beta 1. After incubation, the proliferative response of synovial cells and the expression of Fas antigen and bcl-2 on synovial cells were examined. Finally, Fas antigen-mediated apoptosis of synovial cells was investigated by the addition of anti-Fas antibody. RESULTS: TGF beta 1 enhanced the proliferation of synovial cells in a dose-dependent manner. In addition, Fas antigen expression on synovial cells was inhibited by the addition of TGF beta 1 with up-regulation of bcl-2 expression. The addition of anti-Fas antibody induced synovial cell apoptosis. However, stimulation of synovial cells with TGF beta 1 became markedly resistant to Fas antigen-mediated apoptosis. The results were not affected by the addition of a neutralizing antibody to platelet-derived growth factor type AA (PDGF-AA), which suggests that the effect of TGF beta 1 on synovial cells was promoted via PDGF-AA-independent mechanisms. CONCLUSION: Our results suggest that TGF beta 1 promotes synovial cell proliferation through its mitogenic effect on synovial cells and interference with the apoptotic process mediated by the Fas antigen, resulting in the perpetuation of the synovial hyperplasia in patients with rheumatoid arthritis. 相似文献
62.
Hiroshige Matsuoka Koji Oka Yusuke Yamashita Fumihiro Saeki Shigehisa Fukui 《Microsystem Technologies》2011,17(5-7):983-990
Thermocapillary deformations of an ultra-thin liquid film caused by temperature distribution were three-dimensionally analyzed using the unsteady and linearized long wave equation considering the temperature and film thickness dependence of surface tension. The temperature and film thickness dependence equation for the surface tension of a liquid was firstly established. The temperature dependence of the surface tension was obtained experimentally using a surface tensiometer and the film thickness dependence was obtained theoretically from the corrected van der Waals pressure equation for a symmetric multilayer system. Time evolutions of depression and groove of the ultra-thin liquid film caused by local heating were obtained quantitatively. 相似文献
63.
Kolmogorov introduced the concept of -entropy to analyze information in classical continuous systems. The fractal dimension of a geometric set was introduced by Mandelbrot as a new criterion to analyze the geometric complexity of the set. The -entropy and the fractal dimension of a state in a general quantum system were introduced by one of the present authors (MO) in order to characterize chaotic properties of general states.In this paper, we show that -entropy of a state includes Kolmogorov's -entropy, and that the fractal dimension of a state describes fractal structure of Gaussian measures. 相似文献
64.
65.
Kimiaki Shirahama Yuta Matsuoka Kuniaki Uehara 《Multimedia Tools and Applications》2014,71(3):967-989
An application of Query-By-Example (QBE) is presented where shots that are visually similar to provided example shots are retrieved. To implement QBE, counter-example shots are required to accurately distinguish shots that are relevant to the query from those that are not (Li and Snoek (2009), Yu et al. (2004)). However, there are usually a huge number of shots, not relevant to a particular query, which can serve as counter-example shots. It is difficult for a user to provide counter-example shots that would aid retrieval. Thus, we developed a QBE method based on partially supervised learning where a retrieval model is constructed by selecting counter-example shots from shots without user supervision. To ensure the speed and accuracy of the QBE method, we select a small number of counter-example shots that are visually similar to given example shots but irrelevant to the query. Such shots are useful for characterizing the boundary between relevant and irrelevant shots. For our method, we first filter shots that are visually dissimilar to example shots based on SVMs on a visual feature. Then we filter shots relevant to the query based on concept detection results from pre-constructed classifiers. Shots that pass the above two tests are considered as counter-example shots. Experimental results obtained using TRECVID 2009 video data validate the effectiveness of our method. 相似文献
66.
M. Matsuoka M. Nishide T. Tai J. W. Kim H. Shima T. Katoda 《Integrated ferroelectrics》2014,157(1):39-46
The influence of the post-deposition cooling speed on the domain formation process of PbTiO3 films was investigated using MOCVD equipment combined with in-situ Raman spectroscopy. The accumulation and relaxation of strain during the post-deposition cooling process is responsible for the domain structure. The Curie temperature for fast cooling is lower than that for slow cooling. Additionally, the residual strain with fast cooling is smaller than that with slow cooling. These observations suggest that the volume fraction of the c-domain is larger for fast cooling and that the atmospheric conditions during the first post-deposition cooling process may control the domain structure. 相似文献
67.
Yotaro Akamine Shigeyasu Matsuoka Masakuni Chiba Kunihiko Hidaka 《Electrical Engineering in Japan》2000,132(4):28-33
The breakdown voltages of the longer‐gap configurations in gaseous nitrogen and air that are necessary in designing superconducting electrical power apparatuses are measured at temperatures of 293 and 93 K. The quasi‐uniform electric field made by a sphere‐to‐sphere electrode with a diameter of 150 mm and a gap length of about 10 to 100 mm is used in the measurement of the breakdown voltages. When 50‐Hz ac and dc voltages are applied to the sphere‐to‐sphere gap, the breakdown voltages in nitrogen and air obey Paschen's law even at cryogenic temperatures (93 K). When a 1.4/50‐μs lightning impulse voltage is applied to the gap, the 50% breakdown voltage of nitrogen also obeys Paschen's law under UV irradiation of the cathode electrode. However, the breakdown voltage in air at 93 K is higher in the case of lightning impulse voltage applications, and the delay from impulse voltage application to breakdown occurrence is apparently longer at 93 K than at 293 K. © 2000 Scripta Technica, Electr Eng Jpn, 132(4): 28–33, 2000 相似文献
68.
Masanori Nishino Yusuke Takemori Satoshi Matsuoka Masaki Kanai Takahiro Nishimoto Masahito Ueda Kyoichi Komori 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(3):358-364
A micro gas chromatography (µGC) instrument applying a high performance chip column fabricated on a silicon wafer was developed. Experimental results of the chip column and protyping of a µGC instrument are described. Approximately 35 000 theoretical plates were generated with the chip column coated liquid phase (5% phenyl-/95% dimethyl-polysiloxane). The theoretical plates of the chip column were close to those of the capillary column. Experimental minimum height equivalent to a theoretical plate (HETP, Hmin) of the chip column was 1.2 times higher than the calculated Hmin. A prototype µGC applying the chip column was developed. The µGC generated approximately 35 000 theoretical plates, similar to the theoretical plates obtained by a commercial GC instrument. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
69.
Saburo Matsuoka Hiroyuki Masuda Masuo Shimodaira 《Metallurgical and Materials Transactions A》1990,21(8):2189-2199
The fatigue threshold and low-rate crack propagation properties for a carbon steel, two high-strength steels, and two stainless
steels were investigated in a 3 pct sodium chloride aqueous solution at frequencies between 0.03 and 30 Hz. Tests were conducted
in a manner designed to avoid crack closure. Under freely corroding conditions, the effective values of the threshold stress
intensity factor range, ΔKth,eff, were lower than in air for all of the steels. In particular, the ΔKth,eff values for the carbon and high-strength steels were almost equal to the theoretical ΔKth value of about 1 MPa m1/2 calculated on the basis of the dislocation emission from the crack tip. At a given ΔK level higher than the threshold, the
fatigue crack propagation rates accelerated with decreasing frequency for all of the steels. Under cathodic protection, the
threshold and fatigue crack propagation properties were coincident with those in air regardless of material and frequency.
The observed fatigue crack propagation behavior in a 3 pct NaCl solution was closely related to the corrosion reaction of
the bare surface formed at the crack tip during each loading cycle. 相似文献
70.
Kensuke Miyahara Saburo Matsuoka Tohru Hayashi 《Metallurgical and Materials Transactions A》2001,32(3):761-768
A nanoindentation hardness testing system, including an atomic-force microscope (AFM)-based nanoindentation tester and a calibration
method using electrolytically polished single-crystal metals as references, was proposed. This was applied to a study of the
mechanical properties of fine-grained ferritic steel (grain size of 1.2 μm) and coarse-grained ferritic steel (30 μm). An
empirical function giving the macroscopic hardness for all four reference metals from the nanoindentation force curves was
established. The converted Vickers hardness (HV*) of the coarse-grained steel is almost independent of the indent size. The
fine-grained steel shows only HV* 130 with an indent of only 100 nm, compared with a macroscopic hardness of HV 210. The difference,
HV 80, is considered to reflect the amount of grain-boundary strengthening. The critical indent size for the hardness transition
seems to be around 1 μm, comparable to the grain size of the specimen. This result supports the explanation of grainboundary
strengthening. It is also consistent with Pickering’s work on low-carbon steel, as the estimated locking parameter (k of 2.6×105 N/m3/2) in the Hall-Petch relationship is in good agreement with his value of 2.4×105 N/m3/2. 相似文献