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151.
Improvement of processability of Poly(ε‐caprolactone) (PCL) was achieved by introduction of a branch structure using gamma‐irradiation from a 60Co source. Irradiated PCL has higher molecular weight by producting a branch structure. Hence, the irradiation at a lower dose, such as 3 Mrad, leads to a higher melt viscosity. The branched structure gave improved properties for dynamic viscoelasticity and elongational viscosity. High elongational viscosity was observed by entanglement due to branch chain formed during irradiation, and the elongational viscosity for 3 Mrad is higher than 1.5 Mrad. Due to a higher elongational viscosity, PCL foam can be produced by a molding process. Foam produced from irradiated PCL pellets at 3 Mrad has honeycomb‐like structure, and the foam showed higher enzymatic degradation compared to film samples. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1815–1820, 1999 相似文献
152.
Muto S Tatsumi K Puetter RC Yoshida T Yamamoto Y Sasano Y 《Journal of electron microscopy》2006,55(4):225-230
We applied Pixon deconvolution as introduced in Part I to several practical, examples of low signal-to-noise ratio (SNR), electron energy-loss spectra with a goal toward restoring their fine spectral features and/or improving the energy resolution. We demonstrate that by directly fitting the two-dimensional spectral data recorded on the CCD; the method enables us to reveal fine spectral structures. Consequently, Pixon reconstruction extends the ability to probe electronic states in very spatially localized areas, a capability currently unique to our method. 相似文献
153.
Lili Jiang Xiong Lu Yang Leng Shuxin Qu Bo Feng Jie Weng Fumio Watari 《Materials science & engineering. C, Materials for biological applications》2012,32(4):742-748
This study focused on the effects of microgrooved TiO2 surfaces on osteoblast behavior. Microgrooved TiO2 surfaces with different widths (12 μm and 40 μm) and flat surfaces were fabricated on glass substrates based on the combination of a sol–gel technique and soft-lithography. Osteoblasts (MC3T3-E1) were cultured on the as-prepared microgrooved and flat TiO2 surfaces. Optical microscopy and scanning electron microscopy were used to analyze the adherent cell behavior by examining the cell morphology. Orientation angle analysis indicated that the cells tended to align along the microgrooves. This tendency was stronger on the microgrooves with smaller widths and became weak with increasing width. Alamar Blue assay indicated that the microgrooves restricted cell proliferation and the alkaline phosphatase assay revealed that the microgrooves limited the differentiation rate. This restriction increased with decreasing microgroove width. The surface energy of the TiO2 surfaces was size-dependent and followed the order γ 12 μm < γ 40 μm < γ flat surfaces. Osteoblast proliferation and differentiation on the surface with high surface energy exhibited high proliferation and differentiation rates. These results indicated that surface energy appeared to be a dominant factor for cell activity. Thus, surface energy would be a valuable index for the cell compatibility of a micropatterned surface. 相似文献
154.
155.
Kaneko S. Okabe S. Muto H. Chieko nishida M.Y. Kamei M. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2009,16(1):60-68
As a means of diagnosing partial discharge (PD) signals propagate inside a Gas Insulated Switchgear (GIS), a study for the leakage of electromagnetic waves (EM-waves) emitted from the insulating spacer was implemented. The EM-waves leaking out from the solid insulator have the resonance frequencies depend on the spacing between adjacent bolts in the direction of the flange circumference, because the leakage portion is the equivalent of a slot antenna. In this paper, using an electromagnetic analysis model which has a simulated spacer on a concentrically-shaped GIS tank, the output characteristics of the EM-waves that leaked out from the slit were analyzed under various conditions such as the spacing between adjacent bolts, the width of the spacer, the dielectric constant of the spacer and the form of the flange. Also the actual measurement by the experimental equipment used to simulate the model was implemented for comparison with the analytical results. Consequently, the optimal specifications of the sensor and the measurement method used to achieve highly-sensitive detection for practical use were summarized and proposed as well as evaluating the effectiveness of the electromagnetic analysis model adopted in this paper. 相似文献
156.
We discuss the mode I energy release rate of a rectangular piezoelectric material with a crack under electromechanical loading at cryogenic temperatures. A crack was created normal or parallel to the poling direction, and electric fields were applied parallel or normal to the poling. A plane strain finite element analysis was carried out, and the effects of electric field and localized polarization switching on the energy release rate were discussed for the piezoelectric ceramics at cryogenic temperatures. 相似文献
157.
Yoshiyuki Mizushina Yoshihiro Takahashi Yoshihiro Sato Yasuhiro Yamaguchi Toshifumi Takeuchi Isoko Kuriyama Fumio Sugawara Hiromi Yoshida 《Food chemistry》2012
During the screening of selective DNA polymerase (pol) inhibitors, we isolated two glucosyl compounds, a cerebroside (glucosyl ceramide, AS-1-4, compound 1) and a steroidal glycoside (eleutheroside A, compound 2) from soybean (Glycine max L.). Compounds 1 and 2 selectively inhibited the activity of eukaryotic pol λ in vitro, with IC50 values of 12.2 and 9.1 μM, respectively. These compounds did not influence the activities of other eukaryotic pols including those from the A-family (pol γ), B-family (pols α, δ and ε), and Y-family (pols η, ι and κ), and also showed no effect on the activity of pol β which is of the same family (X) as pol λ. The tendency for in vitro pol λ inhibition by these compounds showed a positive correlation with the in vivo suppression of TPA (12-O-tetradecanoylphorbol-13-acetate)-induced inflammation in mouse ear. These results suggest that these glucosyl compounds from soybean may be useful for their anti-inflammatory properties. 相似文献
158.
Poly(vinyl chloride) (PVC) was ground in air with CaO in the presence of quartz powder as a grinding aid by a small-scale planetary ball mill to investigate the relation of the dechlorination rate of PVC with the impact energy of the balls calculated from a computer simulation based on the Discrete Element Method under various conditions. Mechanochemical dechlorination proceeds as the grinding progresses and is improved with an increase in both the mill speed and the amount of balls introduced into the mill. The same trend can be seen in the relation between the specific normal impact energy of the balls and the rotational speed. The relationship between the observed dechlorination rate and the computed normal impact energy of the balls is linear, with a correlation coefficient of 0.965. This relationship can be used to estimate the dechlorination rate of PVC in a large-scale planetary ball mill. 相似文献
159.
Yuji Wada Hideo Yabashi Masamitsu Tamura Tadao Yoshida Toshio Matsuzawa Fumio Hosoya 《Journal of Energetic Materials》2013,31(1-2):105-132
Abstract The undersand variable gap–initiator test was applied to most Japanese blasting explosive cartridges and found useful as the sensitivity test for the cartridges. The recent Japanese watergel and emulsion explosives were shown to be more shock–sensitive than previous ones. The blast noise in the undersand explosion was shown to decrease when the depth of sand cover the cartridge was increased. For 100g of explosive, a sand layer 20cm deep was effective in reducing the blast noise, when the depth of the sand layer was increased, there was no additional effect. All blasting explosives excluding Kuro Carlit were not ignited by a small gas flame. A cartridge of 100g Kuro Carlit was ignited undersand but did not show the phenomenon of deflagration to detonation 相似文献
160.
A Unique Approach to Characterization of Sol‐Gel‐Derived Rare‐Earth‐Doped Oxyfluoride Glass‐Ceramics
Go Kawamura Ryota Yoshimura Kazunari Ota Song‐Yul Oh Norio Hakiri Hiroyuki Muto Tomokatsu Hayakawa Atsunori Matsuda 《Journal of the American Ceramic Society》2013,96(2):476-480
Using the sol‐gel route Nd3+‐doped oxyfluoride glass‐ceramics were prepared. LiYF4 and YF3 crystals were deposited in the glass‐ceramics and their size, distribution, and amount ratio were varied by changing the compositions and heating temperatures. The incorporation of Nd3+ ions into both the fluoride crystals was confirmed by the high‐resolution elemental mapping of the glass‐ceramics. The incorporated Nd3+ ions showed up and down conversion photoluminescence whose properties were obviously different among the samples. The preliminary site analysis for Nd3+ ions was carried out using a unique approach associated with the Prony series approximation. Finally, the approach was found to be useful for the analysis of materials that are structurally complicating. 相似文献