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971.
Energy conservation policies for the residential sector are evaluated by a model that simulates city-scale energy consumption in the residential sector by considering the diversity of household and building types. In this model, all the households in the city are classified into 380 categories based on the household and building type. The energy consumption for each household category is simulated by the dynamic energy simulation model, which includes an energy use schedule model and a heating and cooling load calculation model. Since the energy usage of each appliance is simulated for every 5 min according to the occupants’ energy usage activity, this model can evaluate not only the energy conservation measures by improving the buildings and appliances but also the measures that involve changing the occupants’ activities. The accuracy of the model is verified by comparing its results with the statistical and the measured data on Osaka City, Japan. Various types of energy conservation measures planned by the Japanese government for the residential sector are simulated and their effects on Osaka City are evaluated quantitatively. The future effects of these combined measures on the energy consumption are also predicted. 相似文献
972.
We report on large-area manipulation of microdroplets by holographic optical tweezers based on a hybrid diffractive system, in which a static computer-generated hologram and a spatial light modulator (SLM) are used. The hybrid diffractive system is useful to manipulate microdroplets on distant areas with the same manner. Experimental results demonstrated that microdroplets were transported successfully in parallel with approximately equivalent velocities over the entire manipulation area. Fusion of microdroplets was also achieved at a position where the optical pattern generated by the SLM alone did not reach. 相似文献
973.
A fundamental study on solidifying phenomenon in a rectangular space filled with water‐saturated porous medium has been carried out with a system, cooled from the upper boundary and heated from below, where vigorous convection develops in the un‐solidified liquid layer. The dynamic response of the solid‐liquid interface to the periodical cooling temperature with the bottom boundary kept at constant temperature TH = 20°C, is investigated experimentally. In particular, the amplitude of the interface and the phase lag in respect to the oscillating cooling temperature have been monitored for various periods and average temperatures. A one‐dimensional numerical model, based on an assumption of constant heat flux from the vigorously convecting liquid regime has been also developed. The numerical model predicts quite well the time‐dependent behavior of the horizontally averaged ice‐layer thickness observed in the experiments. Our general findings are that the amplitude increases proportionally to the temperature fluctuation period and that both the thicker solid layer and the shorter period cause greater phase lags. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(4): 294–308, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20109 相似文献
974.
Kiyoshi Kawaguchi Kenichi Okui Takahiro Shimoura Takaki Ohkouchi Hiroyuki Osakabe Tosihide Ninagawa 《亚洲传热研究》2007,36(4):215-229
In recent years the requirement for reduction of energy consumption has been increasing to solve the problems of global warming and the shortage of petroleum resources. A latent heat recovery type heat exchanger is one of the effective methods of improving thermal efficiency by recovering latent heat. This paper described the heat transfer and pressure loss characteristics of a latent heat recovery type heat exchanger having a wing fin (fin pitch: 4 mm, fin length: 65 mm). These were clarified by measuring the exchange heat quantity, the pressure loss of heat exchanger, and the heat transfer coefficient between outer fin surface and gas. The effects of condensate behavior in the fins on heat transfer and pressure loss characteristics were clarified. Furthermore, the equations for predicting the heat transfer coefficient and pressure loss which are necessary in the design of the heat exchanger were proposed. ©2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(4): 215–229, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20154 相似文献
975.
Cheol Ho Pyeon Jae-Yong Lim Yuki Takemoto Takahiro Yagi Tetsushi Azuma Haksung Kim Yoshiyuki Takahashi Tsuyoshi Misawa Seiji Shiroya 《Annals of Nuclear Energy》2011
At the Kyoto University Critical Assembly (KUCA), spallation neutrons generated by high-energy proton beams are injected into the thorium-loaded systems on March 2010. By combining the Fixed Field Alternating Gradient (FFAG) accelerator with the thorium-loaded system at KUCA, a series of the ADS experiments is carried out under conditions whereby the spallation neutrons are generated at a tungsten target by 100 MeV protons at an intensity of 30 pA. Prompt neutron behavior in the time evolution is observed and thorium fission reactions are attained through the experiments and calculations, respectively. And the effects of neutron leakage and spectrum softening are experimentally observed through the neutron multiplication and reaction rate analyses. From the experimental and numerical analyses, in the future, experimental conditions need to be improved to attain further neutron multiplication using the variation of fuels (thorium, highly-enriched and natural uranium) and moderators (graphite, polyethylene, aluminum and beryllium). 相似文献
976.
977.
Keisuke Yasuda Toshiyuki Masui Takahiro Miyamoto Nobuhito Imanaka 《Journal of Materials Science》2011,46(11):4046-4052
Catalytic combustion of methane was investigated on Pt and PdO-supported CeO2–ZrO2–Bi2O3/γ-Al2O3 catalysts prepared by a wet impregnation method in the presence of polyvinylpyrrolidone. The catalysts were characterized
by X-ray fluorescence analysis, X-ray powder diffraction, X-ray photoelectron spectra, transmission electron microscopy, and
BET specific surface area measurements. The Pt/CeO2–ZrO2–Bi2O3/γ-Al2O3 and PdO/CeO2–ZrO2–Bi2O3/γ-Al2O3 catalysts were selective for the total oxidation of methane into carbon dioxide and steam, and no by-products such as HCHO,
CO, and H2 were obtained. The catalytic activities of the PdO/CeO2–ZrO2–Bi2O3/γ-Al2O3 catalysts were relatively higher than those of the Pt-supported catalysts, due to the facile re-oxidation of metallic Pd
into PdO based on lattice oxygen supplied from the CeO2–ZrO2–Bi2O3 bulk. A decrease in the calcination temperature during the preparation process was found to be effective in enhancing the
specific surface area of the catalysts, whereby particle agglomeration was inhibited. Optimization of the PdO amount and calcination
temperature enabled complete oxidation of methane at temperatures as low as 320 °C on the 11.6 wt% PdO/CeO2–ZrO2–Bi2O3/γ-Al2O3 catalyst prepared at 400 °C. 相似文献
978.
Takahiro Namazu Tomohiro Ishikawa Yoshio Hasegawa 《Journal of Materials Science》2011,46(9):3046-3051
In this article, strength evaluation of silicon carbide (Si–C) ceramics fabricated from polycarbosilane (PCS) precursor is
described. Si–C ceramics was prepared by firing a green body made of the mixture of Si–C nano-powders and a PCS solution at
1,273 K in N2 gas for an hour. To obtain dense Si–C, the solution was infiltrated into the produced body, and then it was fired again.
The polymer infiltration and pyrolysis (PIP) process was conducted up to 12 cycles. Si–C ceramics was diced to be rectangle
shape measuring 1.0 mm × 3.0 mm × 0.5 mm, and was subjected to the three-point bending test for measurement of the Young’s
modulus and bending strength. Si–C specimens fabricated through PIP processes less than 2 cycles showed non-linear force–displacement
curves like a polymer, whereas those through the processes more than 3 cycles showed linear relations and fractured in a brittle
manner. The Young’s modulus of 12-cycles-PIPs specimen was found to be 56 GPa on average, which was approximately 22-fold
of non-PIP specimen. The bending strength was also increased with an increase in the number of PIP process. The maximum value
was found to be 157 MPa. The cause of the influence of PIP process on the mechanical characteristics is discussed using a
PCS-derived Si–C model. 相似文献
979.
Qiang Dong Yoshinori Yonesaki Takahiro Takei Nobukazu Kinomura 《Materials Research Bulletin》2011,46(8):1156-1162
Hexagonal cobalt hydroxide (β-Co(OH)2) nanosheets over a size range from 100 nm to 1 μm were synthesized using a very simple hydrothermal route with cobalt naphthenate as the cobalt source. Additionally, hexagonal cobalt oxide (Co3O4) nanorings over a size range from 100 nm to 1 μm consisting of cubic nanocrystals were obtained via a hydrothermal method using as-prepared β-Co(OH)2 nanosheets as the precursors. A probable mechanism of formation of the hexagonal Co3O4 nanorings is proposed on the basis of time-dependent experimental results. 相似文献
980.
Popa C Kameshima Y Isobe T Nakajima A Okada K 《Journal of hazardous materials》2011,185(2-3):1390-1397
A batch method was used to investigate the uptake of heavy metal cations and anions by the compounds in the CaTiO(3)-CaFeO(2.5) system, in which a series of oxygen vacancies was systematically introduced into a perovskite structure as the x-value of Ca(Fe(x)Ti(1-x))O(3-x/2) was increased. Samples of CaTiO(3), CaFe(0.1)Ti(0.9)O(2.95), CaFe(0.5)Ti(0.5)O(2.75), CaFe(0.67)Ti(0.33)O(2.67) and CaFeO(2.5) were prepared by solid mixing (SM), co-precipitation (CP) and gel evaporation (GE) methods. The resulting samples were calcined at temperatures between 400 and 1000 °C. The target crystalline phases differed according to the preparation method, but in most cases were formed at 700-800 °C. The Ni(2+) sorption isotherms of all the samples were fitted better by the Langmuir model than by the Freundlich model, while in the case of H(2)PO(4)(-) sorption isotherms, these were better fitted by the latter model. The uptake ability increased with increasing x value of the samples. The maximum values for the saturated sorption of Ni(2+) (Q(0)(Ni(2+)) = 2.83 mmol/g) and H(2)PO(4)(-) (K(F)(H(2)PO(4)(-)) = 2.95 mmol/g) were achieved for x = 1 (i.e. CaFeO(2.5)) sample. 相似文献