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991.
We presented an automatic method for detecting and tracking colloidal gold fiducial markers for alignment in electron tomography (ET). The second-order derivative of direction was used to detect a fiducial marker accurately. The detection was optimized to be selective to the size of fiducial markers. A preliminary tracking result from the normalized correlation coefficient was refined using the detector. A constraint model considering the relationship among the fiducial markers on different images was developed for removing outlier. The three-dimensional positions of the detected fiducial markers and the projection parameters of tilt images were calculated for post process. The accuracy of detection and tracking results was evaluated from the residues by the software IMOD. Application on transmission electron microscopic images also indicated that the presented method could provide a useful approach to automatic alignment in ET. 相似文献
992.
Fukusaki E Ikeda T Suzumura D Kobayashi A 《Journal of Bioscience and Bioengineering》2003,96(5):503-505
Arabidopsis thaliana can be a useful model plant in the field of plant molecular biology because it is a sole dicotyledonous plant whose genome sequence has been completely determined at the present time. To develop functional genomics of A. thaliana, a large number of transgenic plants must be produced. However, transformation of the plants requires wide space and long time. For these reasons, a highly efficient method has been desired to be developed. In order to save space, the transformation system was improved, based on a new technology for plant propagation using ceramic tubes. The new method using ceramic tubes facilitated to prepare plants with a uniform growth level. In addition, the colander procedure after infiltration, which is one of tedious procedures, could be omitted. The new system without soil usage could cut down the cleaning up after experiment. 相似文献
993.
Kozo Katayama Akio Saito Yoshio Utaka Akihiro Saito Hideo Matsui Hiromichi Maekawa A.Z.A. Saifullah 《Solar Energy》1981,27(2):91-97
The characteristic variation of the rate of heat transfer to and from a latent heat thermal energy storage capsule was investigated analytically and experimentally. Basic experiments were carried out to simulate a solar energy storage capsule, using a horizontal cylindrical capsule (300 mm length, 40 mm o.d.) filled with naphthalene as the phase change material. The variation of heat flux during the processes of heat storage and removal was measured by a heat flow meter wrapped around the capsule, as the capsule was subjected to stepwise variations of the surface temperature. Finite difference calculations based on heat conduction were also carried out to compare with the experimental results. For the heat removal process, the experimental results and the calculated heat flux agreed well with each other. They showed different characteristic trends for the heat storage process, due to the effects of natural convection. 相似文献
994.
Akio Yamamoto Kuniharu Kinoshita Tomohiro Endo 《Journal of Nuclear Science and Technology》2017,54(4):459-471
In this paper, we estimate prediction errors owing to approximations in calculation models (modeling approximation error) using the data assimilation method. Correlations between the modeling approximation error and neutronics parameters obtained through calculations are evaluated in test configurations and then the evaluated correlations are used to predict the modeling approximation errors in design configuration. Formulae to estimate the modeling approximation error using the correlations are derived based on the minimum variance approach and the physical interpretation of the formulae is discussed through simple cases. The proposed method is applied in 2 × 2 and 3 × 3 fuel assembly geometries using specifications of the KAIST benchmark problem. The correlation between the modeling approximation error and parameters (neutron leakage in each fuel assembly) is estimated in 2 × 2 fuel assemblies and then the modeling approximation error in 3 × 3 fuel assemblies is predicted using the correlation. The calculation results not only indicate feasibility of the present method, but also suggest a need for further investigation on the assumptions used in the present study, i.e. applicability and robustness of the correlation among different geometries. 相似文献
995.
Silicon or titanium was deposited on the filaments of carbon fibres by chemical vapour depositions and the reactions between the deposited silicon or titanium and the carbon fibres were investigated below 1300° C. Between the silicon and the carbon fibres, -SiC layers formed at rates of 1.5 to 3 nm in 3 h at 1300° C. These rates were 10–4 times that of the TiC formation by the reaction of titanium with carbon fibre. Furthermore, the effect of the reaction on fibre strength was investigated. By reaction with silicon, the carbon fibre at a carbonized stage decreased in strength at the beginning of the reaction, but afterwards it recovered to the original level. The carbon fibre at a graphitized stage maintained its original strength after heat treatment for several hours at 1300° C. With the TiC-coated carbon fibres, the carbon fibres decreased in strength following the relation
m d
–1/2, where d is the thickness of the TiC layer. 相似文献
996.
Yutaka Fujimoto Takayuki Yanagida Yuui Yokota Akio Ikesue Akira Yoshikawa 《Optical Materials》2011,34(2):448-451
We investigated basic optical and scintillation properties of pure Y2O3, Tm3+-doped Y2O3, pure Lu2O3 and Nd3+-doped Lu2O3 transparent ceramics made by a sintering method. All ceramic samples showed 60–80% transparency, and some absorption bands due to Nd3+ 4f–4f transition were observed in Nd3+:Lu2O3 ceramic. Both Tm3+:Y2O3 and Nd3+:Lu2O3 ceramics showed sharp luminescence lines corresponding to the 4f–4f transition under 285 nm (Tm3+:Y2O3) and 340 nm (Nd3+:Lu2O3) excitation. The photoluminescence decay times were calculated to be about 24 μs for Tm3+:Y2O3 and 1 μs for Nd3+:Lu2O3, respectively. In radioluminescence measurements, Tm3+ and Nd3+ 4f–4f luminescence were observed for Tm3+-doped Y2O3 and Nd3+-doped Lu2O3 ceramics under 241Am 5.5 MeV α-ray excitation. Finally scintillation light yield was investigated with pulse height analysis. 相似文献
997.
998.
Kazuyuki Kitano Katsuya Hanyuda Eisyun Takegoshi Masatoshi Sawada Yoshio Hirasawa Akio Kosaka 《亚洲传热研究》2006,35(4):245-253
In this study, the effective thermal conductivity of a mixture of magnesia particles and molten nitrate used in a high temperature thermal energy storage system was investigated by a transient hot wire method. The effective thermal conductivity of the mixture was around 2.0W/(m·K) in the temperature range of 423 K to 703 K, although it decreased about 5% with increasing temperature. This value was about 10 times larger than that of the packed bed of magnesia particles including air. The effective thermal conductivity increased about 3% with a 1% increase in the volume ratio of magnesia particles in the mixture with molten nitrate. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(4): 245–253, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20116 相似文献
999.
三峡花岗岩与温度及时间相关的力学性质试验研究 总被引:4,自引:3,他引:4
通过高温下的单轴和三轴抗压蠕变试验,研究了三峡花岗岩单轴应变和粘聚力随温度和时间的变化响应,反映了温度和时间对三峡花岗岩变形特性和强度特性的影响规律;提出了拟合三峡花岗岩单轴应力-应变关系和变形特性和力学模型及其粘聚力随温度和时间变化的经验公式。 相似文献
1000.
Takashi Matsumoto Makoto Satoh Akio Hashimoto 《Computer-Aided Civil and Infrastructure Engineering》1992,7(4):323-332
Abstract: An information-oriented construction system is developed for the management of construction work on the airport island for Kansai International Airport. In this system, virtual grids are placed in the objective operating area. Work result data, which include coordinates, azimuth angle, earth volume, etc., are converted into 'the deposition earth volume' per grid. The consolidation calculation and the earth volume management are also performed. The system comprises the following five subsystems: work result management, deposition configuration management, reclamation configuration management, measurement/survey process and earth volume management. The system also utilizes the computer network connected between the personal computers installed at the site and a large-sized computer at the headquarters ofice to process heavy load calculations. 相似文献