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81.
A new speckle measurement method is proposed by applying a spatial phase shifting method to multi-camera technology in order to perform a high resolution, high speed, and large deformation measurement. It is confirmed that the alignment of optical elements in this method is easier than the ordinary multi-camera methods because the optical system uses only two cameras. The validity of principle of the method is discussed by the results of experiments. It is shown that measurement precision of this method is about 1/50 wavelength in a small deformation measurement. Furthermore, the method is improved for a large deformation measurement method by accumulating the results of the small continuous deformation measurement. The optimum sampling process of the large deformation of an object is proposed in order to detect the phase map of the large deformation. It is confirmed that the large deformation can be precisely measured by this method. 相似文献
82.
Naomi Hirokawa Tsuyoshi Honma Takayuki Komatsu Yasuhiko Benino 《Journal of the American Ceramic Society》2008,91(7):2170-2175
A combination technique of Nd:YAG laser (wavelength: 1064 nm) irradiations and chemical etchings was applied to fabricate microsize U-shaped grooves on the surface of CuO-doped BaO–TiO2 –GeO2 glass, and chemical etching behaviors were examined by using a confocal scanning laser microscope. Continuous-wave Nd:YAG lasers with a power of 0.7–0.8 W were irradiated onto the glass surface and scanned at a speed of 10 μm/s, inducing structural modified lines with refractive index changes. The chemical etching rates for the refractive index changed lines in a nitric acid solution (1 N HNO3 ) were larger than those for the base glass (nonirradiated part). The etching profile was changed gradually from W-shaped to U-shaped grooves with increasing etching time. The sharp bending lines with an angle of 150° and the cross-linked lines were also smoothly etched. The U-shaped grooves with a surface covered by nonlinear optical Ba2 TiGe2 O8 crystals were formed by the crystallization of etched samples. This study proposes that the patterning of microchannels with optical functional surfaces is possible on the glass surface using the present technique. 相似文献
83.
A protein based 3D porous scaffold is fabricated by blending gelatin and albumin. The biomimetic biodegradable gelatin, promoted good cell adhesion and its hydrophilic nature enabled absorption of culture media. Albumin is proposed to serve as a nontoxic foaming agent and also helped to attain a hydrophobic-hydrophilic balance. The hydrophobic-hydrophilic balance and appropriate crosslinking of the scaffold avoided extensive swelling, as well as retained the stability of scaffold in culture medium for long period. The scaffold is found to be highly porous with open interconnected pores. The adequate swelling and mechanical property of the scaffold helped to withstand the loads imparted by the cells during in vitro culture. The scaffold served as a nontoxic material to monolayer of fibroblast cells and is found to be cell compatible. The suitability of scaffold for chondrocyte culture and stem cell differentiation to chondrocytes is further explored in this work. The scaffold provided appropriate environment for chondrocyte culture, resulting in deposition of cartilage specific matrix molecules that completely masked the pores of the porous scaffold. The scaffold promoted the proliferation and differentiation of mesenchymal stem cells to chondrocytes in presence of growth factors. The transforming growth factor, TGFbeta3 promoted better chondrogenic differentiation than its isoform TGFbeta1 in this scaffold. 相似文献
84.
Taka-Aki Mutoh Shinsuke Nakagawa Masayuki Noda Yasuhiko Shiinoki Yasuki Matsumura 《Journal of the American Oil Chemists' Society》2001,78(2):177-183
The relationship between the characteristics of oil droplets and the change in appearance of cream was investigated. The model
creams (40 wt% oil-in-water emulsion), similar to commerical products, were prepared with vegetable fat, milk protein, and
emulsifier. The thermal treatment, in which the cream was exposed to a certain temperature and subsequently recooled, was
performed on the assumption that the temperature was temporarily elevated during transportation and storage of commercial
products. Solidification of the cream was observed when it was exposed to a temperature where there was a small percentage
in solid fat content (SFC) of fat in oil droplets and recooled, whereas the cream remained in the liquid state when it was
exposed to the temperature where SFC was zero and recooled. When the SFC of oil droplets was 0% at the treated temperature,
greater supercooling prior to fat crystallization occurred and the crystallization rate after the initial formation of crystals
was much higher. On the other hand, the polymorphism of fat in the droplets was not directly affected by the thermal treatment.
These results indicate that the crystallization in oil droplets at the heating temperature may be closely connected with the
destablization of oil droplets via a partial coalescence mechanism, which will cause the solidification of cream. 相似文献
85.
86.
Mizuki Tsuta Yasuhiko Sasaki Ikuo Takeuchi Hideki Nakamoto Jun Ishikawa Susumu Kawasaki Junichi Sugiyama Kaori Fujita Masatoshi Yoshimura Mario Shibata Mito Kokawa 《LWT》2014
Flow cytometry (FCM) and aerobic plate count (APC) by the culture method were performed on green tea samples spiked with Escherichia coli type strain NCTC9001 (ATCC11775) solutions of different concentrations. In FCM, fluorescence signals from multiple stained bacteria and other fluorophores are detected using detector channels, and recorded as events with a voltage at each channel. FCM data were analyzed in two ways: conventional and multivariate analysis. In the former, the number of events with voltages larger than the defined threshold values was regarded as the predicted APC. In the latter, voltage histograms of all channels were obtained and merged horizontally to serve as explanatory variables. Then a partial least squares regression (PLSR) model was built to predict APC from the histogram data. The coefficient of determination (R2) and the root mean square error (RMSE) between APC by the culture method and that predicted by conventional FCM were 0.916 and 1.08 cfu/ml2. The APC values predicted by the PLSR model and those measured were in good agreement with R2 of 0.982 and RMSE of 0.417 cfu/ml, which verified the potential of the proposed method for improving APC prediction accuracy by FCM. 相似文献
87.
88.
Yasuhiko Kobayashi 《国际水资源开发杂志》1988,4(1):40-44
This paper charts the decline in the quality of Japan's water resources from about 1955, and the increasingly energetic measures taken to reverse the trend. The standards set by the Basic Law for Environmental Pollution Control are described, and their impact to date is assessed. With respect to human health protection the measures taken have been almost wholly successful, but serious problems of environmental pollution remain, especially in lakes and reservoirs. The main countermeasures against water pollution ‐ effluent control, sewerage and night soil treatment facilities, control of pollutants, steps to arrest eutrophication and prevent groundwater contamination ‐ are described. Finally, the special measures adopted and proposed for lakes and reservoirs are outlined. 相似文献
89.
90.
Juro Watanabe Tadao Iwadate Yasuhiko Tanaka Takeo Yokobori Kotoji Ando 《Engineering Fracture Mechanics》1987,28(5-6):589-600
In order to study the origin of the scatter in the fracture toughness in the transition region and to specify the lower bound of the scatter, approximately 100 pieces 0.5T-CT NiCrMoV steel specimens were tested in the transition region, and their fracture surfaces were investigated. Major portion of the scatter was caused by the scatter in the length of preceding dimple crack which was generated at the fatigue precrack before conversion to final cleavage fracture. A method to predict the lower bound of the scatter in the small-specimen fracture toughness was proposed. It employs Weibull plot of new parameter J1 which represents the scatter in the cleavage strength of material. The cleavage fracture origin may be associated with micro-stress-concentration in the microstructure which may not be caused by the micromechanism in terms of grain size unit. 相似文献