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1.
Abstract The purpose of this exploratory study was to investigate the influence of two individual characteristics (Web experience and academic focus) of adolescents on the Web perception, using off-line questionnaires (a Lickert response scale) constituted on the basis of a series of interviews. Questions concerned: perceptions about the nature of information found in the Web; 'strategies' of access to the interesting Internet sites and the reliability of different information resources (libraries, television, Web, etc.). Results lead to the assumption that adolescents with high Web experience became more critical, less confident and less enthusiastic than adolescents with low Web experience and that, in some dimensions, perceptions of literature students are different to those of science students. Even if some interesting results were obtained, further research is needed to explore users' perceptions related to individuals' characteristics and to determine the generalisability of the influences identified in this exploratory study. 相似文献
2.
M. Peacock 《Journal of Computer Assisted Learning》1988,4(3):162-172
Abstract Selections of English Language and Literature CSE (now GCSE) course work essays are graded by a total of 411 teachers in two forms: handwritten and wordprocessed. Mistakes in the original handwritten versions are not edited out. It is found that the wordprocessed English Language essays are, on average, marked up a grade. However, it is found that relatively high quality English Literature work is not affected. Results suggest:
— that the less directly pupil work is specifically related to an external referent (such as a work of literature), the more likely it is that computer-assisted methods of presentation will significantly enhance its apparent quality relative to handwritten work.
— that relatively lower quality work will tend to be enhanced more than relatively higher quality work.
The implications of the results for examination boards are also considered. 相似文献
— that the less directly pupil work is specifically related to an external referent (such as a work of literature), the more likely it is that computer-assisted methods of presentation will significantly enhance its apparent quality relative to handwritten work.
— that relatively lower quality work will tend to be enhanced more than relatively higher quality work.
The implications of the results for examination boards are also considered. 相似文献
3.
Abstract The key research question for this study was to ask whether or not innovative teaching practices would lead to the development of learning outcomes essential for preparing the younger generation for the challenges of life in the knowledge society of the 21st century, and if so, how are the pedagogical features related to the different learning outcomes. Preliminary analyses of the case study data collected from the SITES M2 Study in Hong Kong reveal that where the development of more significant learning gains were observed, the cases possess characteristics additional to the criteria defined in the Study for selection of innovation. More importantly, it was found that the impact of the pedagogical practices was not determined simply by the aggregation of characteristics of the practices per se , nor on the technologies used, but on whether 'empowerment' permeates the curriculum goal and process. Further, this paper claims that these affective and socio-cognitive learning outcomes are more important as preparation for lifelong learning in the 21st century than 'knowledge management competencies'. 相似文献
4.
Release of the antiaggregation pheromone, verbenone, at 3.8 mg/ day from a concentrated source within a multiple-funnel trap completely inhibited response by the mountain pine beetle (MPB),Dendroctonus ponderosae Hopkins, to attractive semiochemical lures. When aerial applications were simulated and verbenone was released at the same rate from beads lying in a 2×2-m area on the forest floor 15–35 cm below a trap, the response of the MPB was inhibited by only 50%. This reduced inhibition may be explained in part by the photoisomerism of verbenone. When exposed to full sunlight on two occasions, the times required for 50% of verbenone vapors to be converted to chrysanthenone were 75 and 100 min, respectively. Trap and tree-baiting experiments indicated no biological activity of chrysanthenone. Rapid photoisomerization could reduce the concentration of verbenone below biologically active levels and would allow the MPB to colonize trees close to already occupied hosts, contributing to the characteristic clumped distribution of MPB attack. The rate of verbenone photoisomerization may vary according to geographic location, stand elevation and density, and should be considered before verbenone is applied to control the MPB and other bark beetles. 相似文献
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6.
LI SongLin LAI XiaoLing LIU BaoFeng WANG ZhiSuo HE JiaYong & SUN Yi Geophysical Prospecting Center China Earthquake Administration Zhengzhou China Seismological Bureau of Henan Province Zhengzhou 《中国科学:技术科学(英文版)》2011,(6)
A 2-D model of lithospheric velocity structures in the southern part of the North China Craton was obtained using data from the Zhucheng-Yichuan deep seismic sounding profile.Results show that there are great differences in lithospheric structures between two sides of Taihang Mountain.In the eastern region,the lithosphere is thinner,with a thickness of about 70-80 km,while in the western region,the thickness is 85-120 km.There is a jump of the lithospheric thickness across Taihang Mountain gravity anomaly b... 相似文献
7.
Soft errors in 16 Mbit dynamic random access memories (DRAMs) have been investigated using proton microprobes at 400 keV with a spot size of 1 × 1 μm2. The newly developed susceptibility mapping can reveal the correlation between the particle hit-position position and the susceptibility to soft errors in a DRAM. The cell-mode soft-errors were found to take place by the incidence of ions within 6 μm around a monitored cell. These errors would be induced by minority carrier diffusion in a lateral direction. This result manifests the possibility of multiple-bit errors by the incidence of an energetic particle. 相似文献
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9.
基于气体流动计算的摩托车净化系统设计 总被引:1,自引:0,他引:1
排气管内的流场和温度场分布对排气净化系统的性能具有很大的影响,因此弄清楚摩托车排气 管内流场的分布情况十分必要。本文利用FLUENT软件对152QMI摩托车排气管内的流场进行模拟计 算。根据得到的流场分布合理布置催化转化器和二次空气喷射的位置,从而获得比较好的催化净化效 果以降低有害物的排放。 相似文献
10.
Yulan Liang 《Accident; analysis and prevention》2010,42(3):881-890
Driver distraction has become a leading cause of motor-vehicle crashes. Although visual and cognitive distraction has been studied extensively, relatively little research has addressed their combined effects on drivers’ behavior. To fill this gap, a medium-fidelity simulator study examined the driver behavior before, during and after three types of distraction. Driving without distraction was compared to visual distraction, cognitive distraction, and combined visual and cognitive distraction. The results show that the visual and combined distraction both impaired vehicle control and hazard detection and resulted in frequent, long off-road glances. The combined distraction was less detrimental than visual distraction alone. Cognitive distraction made steering less smooth, but improved lane maintenance. All distractions caused gaze concentration and slow saccades when drivers looked at the roadway, and cognitive and combined distraction increased blink frequency. Steering neglect, under-compensation, and over-compensation were three typical steering failures that were differentially associated with the different distractions: steering neglect and over-compensation with visual distraction and under-compensation with cognitive distraction. Overall, visual distraction interferes with driving performance more than cognitive distraction, and visual distraction dominates the performance decrements during combined distraction. These results suggest that minimizing visual demand is particularly important in the design of in-vehicle systems and in the development of distraction countermeasures. 相似文献