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991.
Kai-Wei Tsai Tsung-Hsun Lee Jin-Han Wu Jing-Yuan Jhou Wei-Shun Huang Sung-Nien Hsieh Ten-Chin Wen Tzung-Fang Guo J.C.A. Huang 《Organic Electronics》2013,14(5):1376-1382
Antagonistic responses between magnetoconductance (MC) and magnetoelectroluminescence (MEL) in the polymer light-emitting diodes with an interfacial layer between Al cathode and active layer are simultaneously measured. As the interfacial layer (tetraoctylammonium bromide) is used, the significant increase in the number of injected negative polarons and the blocking of positive polarons promote the triplets-(free polaron) reaction and provide a good explanation for the reason that electroluminescence (EL) efficiency is maximal in the trap free space charge limited current regime at high bias. By fitting of MC and MEL curves using Lorentzian and non-Lorentzian empirical equations, three magnetic field dependent mechanisms, which are the intersystem crossing between singlet/triplet polaron pairs, the triplets-(free polaron) reaction, and the triplets-(trapped polaron) reaction are elucidated. The distribution of the three components is tunable by varying the applied electric field, which primarily modulates the triplets-(free polaron) reaction rate. The results pave a new route toward understanding the mechanism of organic spintronics for developing of multifunctional devices. 相似文献
992.
Experimental data from inhalation studies in mice were used to develop mathematical models of deposition, clearance, and retention kinetics in the respiratory tract for inhaled Ni compounds (high temperature (green) NiO,Ni3S2, and NiSO4.6H2O) in the mouse lung. For deposition, a new model was developed using the experimental data on nasal deposition and lung morphometry by Phalen (1991). Three major mechanisms of airway deposition, including impaction, sedimentation, and diffusion, were considered in the deposition model. Because of the differences in physiological and ventilation conditions, it was found that mice have a lower alveolar deposition fraction than rats when exposed to the same Ni compounds. In the development of a clearance model, a single compartment model in the lung was used and a general assumption was made that the clearance of the insoluble and moderately soluble Ni compounds (high temperature (green) NiO and Ni3S2, respectively) depends highly on the volume of retained particles in the lungs. As for the highly soluble Ni compound (NiSO4.6H2O), the clearance rate coefficient was assumed to depend on the retained particle mass and total alveolar surface. The retention half time, however, was found to increase with the lung burden for high temperature (green) NiO and NiSO4.6H2O particles, but to decrease with the lung burden for Ni3S2 particles. The retention half times for high temperature (green) NiO and Ni3S2 particles in mice are shorter than in rats, whereas the retention half time for NiSO4.6H2O particles is the same for both species. 相似文献
993.
Chao-Chi Hong Chuang-Yuan Lee Yuan-Long Hsieh Chean-Chung Liu Fong I.-K. Jenn-Gwo Hwu 《Semiconductor Manufacturing, IEEE Transactions on》2001,14(3):227-230
A new repeated spike oxidation (RSO) method used in a rapid thermal processing system was proposed in this work. Simulation results predict the temperature distribution on the wafer would be improved by this RSO method. We proposed that the improvement in wafer temperature uniformity is mainly caused by self-compensation in radiation heat absorption rate. Experimental data pointed out that the new method can produce more uniform oxide thickness than the conventional one under an intentionally created nonuniform heating environment 相似文献
994.
Chih-Shun Ding Cheng-Ta Hsieh Pedram M. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2000,8(5):584-593
In this paper, we propose two efficient statistical sampling techniques for estimating the total power consumption of large hierarchical circuits. We first show that, due to the characteristic of the sampling efficiency in Monte Carlo simulation, granularity of samples is an important issue in achieving high overall efficiency. The proposed techniques perform sampling both temporally (across different clock cycles) and spatially (across different modules) so that a smaller sample granularity can be achieved while maintaining the normality of samples. The first proposed technique, which is referred to as the module-based approach, samples each module independently when forming a power sample. The second technique, which is referred to as the cluster-based approach, lumps the modules of a hierarchical circuit into a number of clusters on which sampling is then performed. Both techniques adapt stratification to further improve the efficiency. Experimental results show that these techniques provide a reduction of 23× in simulation run time compared to existing Monte-Carlo simulation techniques 相似文献
995.
H. S. Chou C. Y. Yang B. J. Hsieh S. S. Chang 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2001,16(3):3087
Studies of liquefaction-related damages on underground structures are limited and sometimes controversial. Liquefaction potential analysis is essential in tunnel design in liquefiable soils. A Taipei Rapid Transit System (TRTS) tunnel site in Taipei County was selected to study the risk under liquefaction-related damage. The liquefaction risk index was applied for assessment of the overall liquefaction risks and liquefaction-induced settlement at the interest site. The anti-liquefaction measure for shield tunneling by using secondary injection grouting was discussed to eliminate the flow of liquefied soils and reduce the liquefaction-induced settlement. 相似文献
996.
Hsieh Peggy ; Acee Taylor; Chung Wen-Hung; Hsieh Ya-Ping; Kim Hyunjin; Thomas Greg D.; You Ji-in; Levin Joel R.; Robinson Daniel H. 《Canadian Metallurgical Quarterly》2005,97(4):523
The authors examined intervention studies that appeared in 4 educational psychology journals (Cognition & Instruction, Contemporary Educational Psychology, Journal of Educational Psychology, Journal of Experimental Education) and the American Educational Research Journal (AERJ) in 1983 and from 1995 to 2004. The majority of studies included adults (age 18 and older) as participants, administered brief (less than 1 day) interventions, assessed intervention effects immediately following the intervention, and did not report treatment integrity. Most studies included multiple outcome measures and exhibited an increase in effect-size reporting from 4% in 1995 to 61% in 2004. The percentage of total articles based on randomized experiments decreased over the 21-year period in both the educational psychology journals (from 40% in 1983 to 34% in 1995 to 26% in 2004) and AERJ (from 33% to 17% to 4%). Limitations of the study and future research issues are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
In recent years, the use of computer graphic techniques to produce three-dimensional (3-D) and reformatted images from a set of axial computed tomography (CT) images has gained significant interest. In most cases, the CT images are generated with the projection data set weighted prior to reconstruction, to combat motion artifacts, data inconsistency, or redundant data samples. In this paper, we investigate the potential bias introduced to the reconstruction as a result of the interaction of the projection weights and the isocenter misalignment (ISM). We demonstrate that when the weights applied to the conjugate rays are significantly different, bias will result which favors the sample with a higher weight. Although the error is not easily detected in axial CT images, it can be quite visible in 3-D or multiplanar reformatted (MPR) images. In this paper, we first present a theoretical framework to analyze and predict the bias. The theoretical prediction is validated by both computer simulations and phantom experiments. Several schemes to combat this artifact are subsequently presented; and their effectiveness is demonstrated. 相似文献
998.
Kuo-Ching Huang Yean-Kuen Fang Dun-Nian Yaung Chii-Wen Chen Mong-Song Liang Jang-Cheng Hsieh Chi-Wen Su Kuei-Ying Lee 《Electron Device Letters, IEEE》1999,20(1):36-38
The effects of different tungsten polycide technologies on the effective channel length and electrical performance of scaled CMOS transistors fabricated by rapid thermal annealing (RTA) have been investigated. Contrary to previous studies, it is found that the sputtered WSix device produces a larger reduction in channel length, a result which is confirmed by gate-to-drain overlap capacitance CGD measurement. Experiments also indicate that the sputtered WSix devices possess a lower driving ability, and have higher off state leakage not only for the short channel but also for the long channel range 相似文献
999.
Task switching requires maintaining readiness to execute any task of a given set of tasks. However, when tasks switch, the readiness to execute the now-irrelevant task generates interference, as seen in the task rule incongruence effect. Overcoming such interference requires fine-tuned inhibition that impairs task readiness only minimally. In an experiment involving 2 object classification tasks and 2 location classification tasks, the authors show that irrelevant task rules that generate response conflicts are inhibited. This competitor rule suppression (CRS) is seen in response slowing in subsequent trials, when the competing rules become relevant. CRS is shown to operate on specific rules without affecting similar rules. CRS and backward inhibition, which is another inhibitory phenomenon, produced additive effects on reaction time, suggesting their mutual independence. Implications for current formal theories of task switching as well as for conflict monitoring theories are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Chun-Ming Hsieh Hong Chen Ryozo Ooka JaeOck Yoon Shinsuke Kato Kiyoshi Miisho 《Building Simulation》2010,3(1):51-61
The present study explains the application of a numerical simulation to investigate the thermal environment of a new riverside
residential development in summer. The case study area consists of more than one hundred two-story detached houses built next
to a river near Tokyo, Japan. According to the meteorological data, prevailing wind directions are at an angle to the northbound
river flow affecting the microclimate of the study area in terms of surface temperature of land and buildings, air temperature
and wind distribution at pedestrian height. These factors have been estimated using the stepwise CFD (computational fluid
dynamics) simulation of radiation, conduction and convection. This method leads to an improvement of outdoor thermal environment
by manipulating the site design and layout planning scenarios. The effect of river, permeable pavements and green space on
thermal environment is examined by the site design options. Likewise, the impact of building arrangement is evaluated using
alternative layout planning scenarios. In total, five scenarios have been simulated for the proposed sustainable development
as explained in the paper. Above simulations provided an insight into the mitigation effects of each countermeasure. It is
also shown that the management of inflow paths and the creation of wind paths for the interior of the site have the potentials
to improve the outdoor thermal environment of riverside residential development. 相似文献