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981.
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The distribution coefficients of silver and gold between copper and matte phases have been measured at 1400 and 1500 K. For
0.07 to 0.13 wt pct silver and 0.0022 to 0.0042 wt pct gold in ironfree matte, the distribution coefficients of silver and
gold are independent of concentration. For iron-bearing matte, the distribution coefficients of silver and gold are correlated
with iron content of the matte. From the measured values of the distribution coefficients of silver and gold, the activity
coefficients of AgS0.5 and Au in copper-saturated matte have been calculated. The following correlations express these results: log γ°AgS0.5(1) = -425/T - 0.074 + 0.09NFeS, log γ°Au(1) =-7620/T + 7.25 forT = 1400 to 1500 K and NFeS, mole fraction of FeS = 0 to 0.28. The present values of the activity coefficients of AgS0.5 must be used exclusively in conjunction with the following Gibbs free energy of formation: 2Ag(l) + 1/2S2(g) = Ag2S(l), ΔG° = -23960 + 10.295T (cal/mol).
M. Nagamori, formerly Associate Professor of Metallurgy at The University of Utah. 相似文献
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986.
The study offers insights into pilot ability to anticipate consequences of actions and how this ability changes with experience. Novice and expert pilots completed trials in which 3 screens depicted a control movement (or control movements), a cockpit flight situation, or a change in flight situation. Changes depicted in the 3rd screen of each trial were consistent, inconsistent with the mental model of the effect of the control movement or movements, or inconsistent with the application of the control movement(s) to the current flight situation. Pilots indicated whether the depicted change was inconsistent or consistent with their expectations, and accuracy of consistency judgments was greater for mental-model than for situation-model inconsistent statements. Experts are more accurate than novices, particularly for trials that involve multiple, meaningfully related control movements. Expert ability to organize information into meaningful units appears to facilitate future flight state projections, and projection failures appear to result from situation- rather than mental-model failures. Actual or potential applications of this research include analysis of flight situation awareness and flight performance errors. 相似文献
987.
Wan-Suk?YooEmail author Jeong-Han?Lee Jeong-Hyun?Sohn Su-Jin?Park Oleg?Dmitrochenko Dmitri?Pogorelov 《Journal of Mechanical Science and Technology》2004,18(5):742-752
Many papers have studied computer simulations of elastic bodies undergoing large deflections and large deformations. But there
have not been many attempts to check the validity of the numerical formulations because the simulation results could not be
matched without correct input data such as material properties and damping effects. In this paper, these values are obtained
from real experiment with a high-speed camera and a data acquisition system. The simulation results with the absolute nodal
coordinate formulation (ANCF) are compared with the results of real experiments. Two examples, a thin cantilever beam and
a thin plate, are studied to verify whether the simulation results are well matched to experimental results. 相似文献
988.
Production of granular activated carbon from waste walnut shell and its adsorption characteristics for Cu(2+) ion 总被引:4,自引:0,他引:4
Production of granular activated carbon by chemical activation has been attempted employing walnut shells as the raw material. The thermal characteristics of walnut shell were investigated by TG/DTA and the adsorption capacity of the produced activated carbon was evaluated using the titration method. As the activation temperature increased, the iodine value increased. However, a temperature higher than 400 degrees C resulted in a thermal degradation, which was substantiated by scanning electron microscopy (SEM) analysis, and the adsorption capacity decreased. Activation longer than 1h at 375 degrees C resulted in the destruction of the microporous structure of activated carbon. The iodine value increased with the increase in the concentration of ZnCl2 solution. However, excessive ZnCl2 in the solution decreased the iodine value. The extent of activation by ZnCl2 was compared with that by CaCl2 activation. Enhanced activation was achieved when walnut shell was activated by ZnCl2. Applicability of the activated carbon as adsorbent was examined for synthetic copper wastewater. Adsorption of copper ion followed the Freundlich model. Thermodynamic aspects of adsorption have been discussed based on experimental results. The adsorption capacity of the produced activated carbon met the conditions for commercialization and was found to be superior to that made from coconut shell. 相似文献
989.
Proposed is a new type of packaging technology, `pocket embedding package', using selectively anodised aluminium substrate. In this technology, chips can be embedded inside aluminium substrate so that an ultra-thin and compact type of package can be achieved. A monolithic microwave integrated circuit dice with 120 mum thickness has been successfully embedded inside the substrate with a tolerance of less than 5 mum, and 300 mum of total thickness can be achieved with excellent thermal dissipation 相似文献
990.
Byung-Ho Lee Jin-Sik Cheon Yang-Hyun Koo Je-Yong Oh Jeong-Sik Yim Dong-Seong Sohn M. Baryshnikov A. Gaiduchenko 《Journal of Nuclear Materials》2007,360(3):315-320
The specific heat capacities of un-irradiated and irradiated metallic Zr–40 wt%U fuel have been measured between 50 °C and 1000 °C with a differential scanning calorimetry. The irradiated fuels have three different burnup levels of 0.38, 0.70 and 0.92 g-fission product (FP)/cm3. The measured specific heat for the un-irradiated fuel is representative and consistent with the values estimated from the Neumann–Kopp rule. The irradiated fuels exhibited a complicated behavior of the heat capacities. The unique characteristics of the specific heat capacities can be explained by the recovery of radiation damage, the formation of fission gas bubbles and fission gas release, and a phase transition in the irradiated fuels. An examination of the microstructure revealed that multiple large bubbles were formed in the irradiated fuel during specific heat measurement. The measured specific heat is expected to enable us to estimate the stored energy in the metallic fuel during certain accident scenarios and to determine the thermal conductivity of zirconium–uranium metallic fuel. 相似文献