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141.
142.
Robinson-Whelen Susan; Hughes Rosemary B.; Powers Laurie E.; Oschwald Mary; Renker Paula; Swank Paul R.; Curry Mary Ann 《Canadian Metallurgical Quarterly》2010,55(2):97
Objective: To evaluate the effects of a computerized disability-specific abuse assessment intervention on abuse awareness, safety self-efficacy, and safety promoting behaviors of women with diverse disabilities. Research Design: A randomized control group design was used, with the intervention group completing the assessment intervention both at Time 1 (T1) and 3 months later at Time 2 (T2) and control participants completing it for the first time at T2. Analyses compared intervention and control groups at T2 and evaluated change over time in intervention group participants. The relationship between outcome variables (abuse awareness, safety self-efficacy, safety behaviors) was also explored. Results: The intervention group had greater abuse awareness than the control group at T2, and abuse awareness increased from T1 to T2 among women in the intervention group, particularly among women who had experienced little or no abuse in the past year. Both abuse awareness and safety self-efficacy were significantly related to safety behaviors. Conclusions: The computerized program offers promise as a nonthreatening method of conducting abuse assessments among women with disabilities while also serving as an intervention to enhance abuse awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
143.
An overview of FDA medical device regulation as it relates to deep brain stimulation devices. 总被引:1,自引:0,他引:1
Carlos Pe?a Kristen Bowsher Ann Costello Robert De Luca Sara Doll Khan Li Marie Schroeder Theodore Stevens 《IEEE transactions on neural systems and rehabilitation engineering》2007,15(3):421-424
The United States Food and Drug Administration (FDA) is charged with assuring the safety and effectiveness of a variety of medical products and the FDA's Center for Devices and Radiological Health is responsible for premarket and postmarket regulation of medical devices. In this paper, we review--from device classification and clinical studies to the final marketing application--FDA's premarket requirements and postmarket requirements as they relate to deep brain stimulation devices. 相似文献
144.
Ann Heylighen Monika Rychtáriková Gerrit Vermeir 《Universal Access in the Information Society》2010,9(3):283-292
Inclusive design aims at objects and environments that are accessible, usable and comfortable for all people throughout their entire lifespan. In architecture, this aim is usually associated with physical accessibility. Yet acoustic qualities may considerably impact usability and comfort as well, especially in spaces for listening. This case study explores the notion of acoustic comfort for all in the context of university education. One auditorium, situated in a historic building and subject to renovation in the near future, is studied in detail: acoustic obstacles are identified in collaboration with user/experts and are measured in situ; specific interventions are proposed in consultation with building professionals, technicians and conservation specialists and are tested using dedicated acoustic simulation software. The study draws attention to the importance of acoustic comfort for all and offers a first view of which solutions are possible and desirable and how these can be obtained. 相似文献
145.
Recent research has shown that when people perceive a causal relation between 2 events, they “compress” the intervening elapsed time. The present work shows that a na?ve mechanical–physical conception of causality, in which causal forces are believed to dissipate over time, underlies the estimates of shorter elapsed time. Being primed with alternative, nondissipative causal mechanisms and having the cognitive capacity to consider such mechanisms moderates the compression effect. The studies rule out similarity, mnemonic association, and anchoring as alternative accounts for the effect. Taken together, the findings support the hypothesis that causal cognition plays a major role in judgments of elapsed time. The implications of the compression effect on the timing of future actions, persistence, and causal learning are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
多电平电流源逆变器因具有高安全性、低输出谐波特性等优点得到广泛关注。提出了一种开关电感型单相五电平电流源逆变器,其直流控制单元采用Buck结构,为电感提供了独立的充放电回路,实现了电感电流控制与输出电流控制的完全解耦,使用较小电感即可控制电流稳定。所提逆变器采用开关电感结构形成多电平输出,减少了器件数目,利用其高度对称性可简化外围电路设计。针对于单相逆变器输入侧电感电流存在二倍频波动的问题,在传统比例积分控制的基础上,增加功率前馈控制,以储能电感在每个开关周期内实现电流恒定作为先决条件,折算不同状态下直流侧开关器件的占空比扰动量,在不增加电路复杂度的前提下,采用较少器件和小储能电感有效抑制了电感电流的二倍频波动,减小了输出电流中3次谐波含量和总谐波畸变率,提高了输出电能质量。最后,通过仿真和实验验证了所提拓扑和控制策略的可行性。 相似文献
147.
Mark Scott Cooper William Robert Hardin Timothy Wayne Petersen Rose Ann Cattolico 《Journal of Bioscience and Bioengineering》2010,109(2):198-201
We report here that BODIPY 505/515, a green lipophilic fluorescent dye, serves as an excellent vital stain for the oil-containing lipid bodies of live algal cells. BODIPY 505/515 vital staining can be used in combination with fluorescent activated cell sorting to detect and isolate algal cells possessing high lipid content. 相似文献
148.
The effects of precursor and calcination temperature on the nano morphology of ruthenium dioxide on titanium, prepared from thermal decomposition of aqueous salt solutions were investigated. Transmission electron microscopy, X-ray diffraction, gas porosimetry and cyclic voltammetry showed that lower calcination temperature yielded smaller crystallites. The crystallites were between 6 and 22 nm in diameter. When using ruthenium nitrosyl nitrate the firing temperature had a large impact on the grain size, but for chloride there was only a minor effect in the temperature range 350-550 °C. 相似文献
149.
Ramadan SS Heyn C Mackenzie LT Chambers AF Rutt BK Foster PJ 《Magma (New York, N.Y.)》2008,21(4):251-259
INTRODUCTION: The use of MRI with iron-based magnetic nanoparticles for imaging cells is a rapidly growing field of research. We have recently reported that single iron-labeled cells could be detected, as signal voids, in vivo in mouse brains using a balanced steady-state free precession imaging sequence (b-SSFP) and a customized microimaging system at 1.5 T. METHODS: In the current study we assess the benefits, and challenges, of using a higher magnetic field strength for imaging iron-labeled cells with b-SSFP, using ex vivo mouse brain specimens imaged with near identical systems at 1.5 and 3.0 T. RESULTS: The substantial banding artifact that appears in 3 T b-SSFP images was readily minimized with RF phase cycling, allowing for banding-free b-SSFP images to be compared between the two field strengths. This study revealed that with an optimal 3 T b-SSFP imaging protocol, more than twice as many signal voids were detected as with 1.5 T. CONCLUSION: There are several factors that contributed to this important result. First, a greater-than-linear SNR gain was achieved in mouse brain images at 3 T. Second, a reduction in the bandwidth, and the associated increase in repetition time and SNR, produced a dramatic increase in the contrast generated by iron-labeled cells. 相似文献
150.
Dr. Balamurugan Dhayalan Dr. Ann Fitzpatrick Dr. Kalyaneswar Mandal Dr. Jonathan Whittaker Prof. Dr. Michael A. Weiss Prof. Dr. Andrei Tokmakoff Prof. Dr. Stephen B. H. Kent 《Chembiochem : a European journal of chemical biology》2016,17(5):415-420
Isotope‐edited two‐dimensional Fourier transform infrared spectroscopy (2 D FTIR) can potentially provide a unique probe of protein structure and dynamics. However, general methods for the site‐specific incorporation of stable 13C=18O labels into the polypeptide backbone of the protein molecule have not yet been established. Here we describe, as a prototype for the incorporation of specific arrays of isotope labels, the total chemical synthesis—via a key ester insulin intermediate—of 97 % enriched [(1‐13C=18O)PheB24] human insulin: stable‐isotope labeled at a single backbone amide carbonyl. The amino acid sequence as well as the positions of the disulfide bonds and the correctly folded structure were unambiguously confirmed by the X‐ray crystal structure of the synthetic protein molecule. In vitro assays of the isotope labeled [(1‐13C=18O)PheB24] human insulin showed that it had full insulin receptor binding activity. Linear and 2 D IR spectra revealed a distinct red‐shifted amide I carbonyl band peak at 1595 cm?1 resulting from the (1‐13C=18O)PheB24 backbone label. This work illustrates the utility of chemical synthesis to enable the application of advanced physical methods for the elucidation of the molecular basis of protein function. 相似文献