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991.
Dan Ding Guan Wang Jianzhao Liu Kai Li Kan‐Yi Pu Yong Hu Jason C. Y. Ng Ben Zhong Tang Bin Liu 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(22):3523-3530
Herein is reported the synthesis of gadolinium ion (Gd(III))‐chelated hyperbranched conjugated polyelectrolyte (HCPE‐Gd) and its application in fluorescence and magnetic resonance (MR) dual imaging in live animals. The synthesized HCPE‐Gd forms nanospheres with an average diameter of ~42 nm measured by laser light scattering and a quantum yield of 10% in aqueous solution. The absorption spectrum of HCPE‐Gd has two maxima at 318 and 417 nm, and its photoluminescence maximum centers at 591 nm. Confocal laser scanning microscopy studies indicate that the HCPE‐Gd is internalized in MCF‐7 cancer cell cytoplasm with good photostability and low cytotoxicity. Further fluorescence and MR imaging studies on hepatoma H22 tumor‐bearing mouse model reveal that HCPE‐Gd can serve as an efficient optical/MR dual‐modal imaging nanoprobe for in vivo cancer diagnosis. 相似文献
992.
Jienan Chen Peng Zhan Ben Koopman Guigan Fang Yingqiao Shi 《Clean Technologies and Environmental Policy》2012,14(5):899-904
The Gordonia strain JW8 was successfully isolated, characterized, and tested for bioaugmentation of pulp and paper wastewater. With significant degradation of alkaline lignin, JW8 has the potential to render pulp and paper wastewater more biodegradable, which is of much interest to wastewater treatment. The sequencing batch reactor (SBR) inoculated with JW8 significantly enhanced the organic pollutants removal of pulp and paper wastewater compared to the control, achieving the best removal rates of 96.4% and 87.8% for biochemical oxygen demand (BOD) and chemical oxygen demand (COD), respectively. A considerable decrease of BOD/COD ratio in wastewater was also achieved in the bioaugmented SBR. However, a drawback caused by JW8 inoculation was the resultant high sludge volume index and biological foaming and bulking, which can be controlled by food/mass adjustment. The denaturing gradient gel electrophoresis analysis suggested that bioaugmentation with JW8 had a slight effect on the microbial dynamics, but more research is needed to understand the relationship between the microbial dynamics and pollutant removal. 相似文献
993.
994.
H. Dhaou N. Ben Khedher S. Mellouli A. Souahlia F. Askri A. Jemni S. Ben Nasrallah 《International Journal of Thermal Sciences》2011,50(12):2536-2542
The reaction time of hydrogen in metal-hydride vessels (MHVs for short) is strongly influenced by the heat transfer from/to the hydride bed. In the present work an experimental study of the geometric and the operating parameters of a finned spiral heat exchanger has been carried out to identify their influence on the performance of the charging process of the MHV. The experimental results show that the charge time of the reactor is considerably reduced, when finned spiral heat exchanger is used. In addition, the effect of different parameters (flow mass and temperature of the cooling fluid, applied pressure of hydrogen in the case of absorption and desorption) has been discussed and obtained results show that a good choice of these parameters is important. 相似文献
995.
从SSSC定阻抗和定电压两种控制角度出发,分别将其视为可控电容器和可控电压源,分析了其各自的运行特点,并建立含SSSC的单机无穷大系统数学模型,运用了逆系统和滑模控制的方法分别对建立的多阶非线性系统模型进行控制设计,通过仿真验证了该控制对控制目标具有很好的稳定性和鲁棒性. 相似文献
996.
This paper deals with a numerical analysis of the evaporation of binary liquid film. The film is falling down on one plate of a vertical channel under mixed convection channel. The first plate of a vertical channel is externally submitted to a uniform heated flux q1 while the second one (y = d) is dry and isothermal. The liquid mixture consists of water (the more volatile component) and ethylene glycol while the gas mixture has three components: dry air, water vapour and ethylene-glycol vapour. The results concern the effects of the inlet parameters in the gas and in the liquid film on the interfacial pressure, temperature and concentration profiles. The evolutions of the heat fluxes and of the water and mixture evaporation rates have been analysed. Results obtained show, in particular, that it is possible to increase the accumulated evaporation rate of water and of the liquid mixture when the inlet liquid concentration of ethylene glycol (the less volatile component) is less than 40%. This result has been explained by the fact that an increase of the inlet liquid concentration of ethylene glycol has two antagonistic effects on the accumulated evaporation rates of water and of liquid mixture. 相似文献
997.
Food-deprived rats learned to avoid a flavor negatively correlated with access to a rich nutrient, 20% maltodextrin (20M) solution. This avoidance in two-bottle choice tests was produced by training consisting of either an unpaired condition where sessions of unflavored 20M were intermixed with sessions of 2 or 3% maltodextrin (2M or 3M) flavored with salt (Experiment 1) or almond (Experiments 3 and 4) or a differential conditioning procedure where one flavor was mixed with 20M and another with 2M (Experiment 2). Avoidance was counter-conditioned by mixing the target flavor with 20M (Experiment 1), generalized to a neutral context (Experiment 3), and displayed strong resistance to extinction (Experiment 4). The results demonstrated that food avoidance learning can occur in the absence of an aversive unconditioned stimulus and indicated that unpaired control groups and differential conditioning procedures may be misleading in flavor preference learning research when further control conditions are absent. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Integrated Framework for Quantifying and Predicting Weather-Related Highway Construction Delays 总被引:1,自引:0,他引:1
Somkiat Apipattanavis Kevin Sabol Keith R. Molenaar Balaji Rajagopalan Yunping Xi Ben Blackard Shekhar Patil 《Canadian Metallurgical Quarterly》2010,136(11):1160-1168
Constant exposure to the environment makes highway construction highly dependent on weather. However, highway construction contracts are often unclear about the potential influence of weather-related delays on highway construction project schedules. There is a need to discourage litigation arising from weather-related delays by including in contracts a reasonable number of nonwork days as a consequence of adverse weather and providing an equitable criteria for the course of action when the predictions in the contracts turn out to be inaccurate. To address this need, an integrated framework consisting of the following two key components is proposed: (1) identification of attributes of weather that cause construction delays and (2) generation of synthetic weather sequences using a stochastic weather generator to quantify and provide probabilistic forecasts of weather threshold values. The utility of this framework is demonstrated through its application to construction work on a project in Texas. The use of probabilistic forecast of construction delay attributes provided by a semiparametric weather generator in this research is an example of interdisciplinary study to help address this problem. The result of the research is better decision support for agencies who wish to author contracts that more equitably allow for the influence of weather during construction. 相似文献
999.
1000.
H. Ben Naceur T. Mzoughi I. Moussa A. Rebey B. El Jani 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(3-4):236-240
InAs epilayers were grown by atmospheric pressure metal–organic vapor phase epitaxy on GaAs (1 0 0) exactly oriented substrates and misoriented by 2° and 10° toward [1 1 1]A. The layers had varying thicknesses and were deposited under the same growth conditions. Atomic force microscopy analysis show that surface morphology depends on surface misorientation and presents a low root mean square. High resolution X-ray diffraction analysis and Hall effect measurements were preformed to check the substrate misorientation effect on the crystalline quality and electrical properties respectively. 相似文献