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101.
Yoon Carolyn; Feinberg Fred; Hu Ping; Gutchess Angela Hall; Hedden Trey; Chen Hiu-Ying Mary; Jing Qicheng; Cui Yao; Park Denise C. 《Canadian Metallurgical Quarterly》2004,19(3):379
Understanding how aging influences cognition across different cultures has been hindered by a lack of standardized, cross-referenced verbal stimuli. This study introduces a database of such item-level stimuli for both younger and older adults, in China and the United States, and makes 3 distinct contributions. First, the authors specify which item categories generalize across age and/or cultural groups, rigorously quantifying differences among them. Second, they introduce novel, powerful methods to measure between-group differences in freely generated ranked data, the rank-ordered logit model and Hellinger Affinity. Finally, a broad archive of tested, cross-linguistic stimuli is now freely available to researchers: data, similarity measures, and all stimulus materials for 105 categories and 4 culture-by-age groups, comprising over 10,000 fully translated unique item responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
This paper proposes a new LDMOSFET structure with a trenched sinker for high‐power RF amplifiers. Using a low‐temperature, deep‐trench technology, we succeeded in drastically shrinking the sinker area to one‐third the size of the conventional diffusion‐type structure. The RF performance of the proposed device with a channel width of 5 mm showed a small signal gain of 16.5 dB and a maximum peak power of 32 dBm with a power‐added efficiency of 25% at 2 GHz. Furthermore, the trench sinker, which was applied to the guard ring to suppress coupling between inductors, showed an excellent blocking performance below ?40 dB at a frequency of up to 20 GHz. These results confirm that the proposed trenched sinker should be an effective technology both as a compact sinker for RF power devices and as a guard ring against coupling. 相似文献
103.
Jae-Duk Lee Jeong-Hyuk Choi Donggun Park Kinam Kim 《Electron Device Letters, IEEE》2003,24(12):748-750
In contrast to the conventional theories, we have revealed that the most distinguished mechanism in the data retention phenomenon after Fowler-Nordheim (FN) stress in sub-100 nm NAND Flash memory cells is the annihilation of interface states. Interface state generation rate increases rapidly as the channel width of NAND flash cell decreases. Comparison of interface states and stress-induced leakage current (SILC) component during retention mode shows that the annihilation of interface states strongly affects data retention characteristics of the programmed cells. 相似文献
104.
Min-Seok Park Vladislav P. Vislovskiy Jong-San Chang Yong-Gun Shul Jin S. Yoo Sang-Eon Park 《Catalysis Today》2003,87(1-4):205-212
Alumina-supported vanadium oxide, VOx/Al2O3, and binary vanadium–antimony oxides, VSbOx/Al2O3, have been tested in the ethylbenzene dehydrogenation with carbon dioxide and characterized by SBET, X-ray diffraction, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction and CO2 pulse methods. VSbOx/Al2O3 exhibited enhanced catalytic activity and especially on-stream stability compared to VOx/Al2O3 catalyst. Incorporation of antimony into VOx/Al2O3 increased dispersion of active VOx species, enhanced redox properties of the systems and formed a new mixed vanadium–antimony oxide phase in the most catalytically efficient V0.43Sb0.57Ox/Al2O3 system. 相似文献
105.
A new discontinuous modulation method based on space-vector control is proposed and analyzed. The proposed technique employs a pulse-dropping method and is designed in the time domain. It features a very wide modulation range while maintaining the required waveform qualities and switching numbers in the overmodulation region. Since the modulation method and modulation index equation are simple, the proposed technique can be easily implemented by software and is applicable to the overmodulation region in ac motor drives. The performance indexes are discussed and experiments have been performed. 相似文献
106.
Yan R.-H. Lee K.F. Jeon D.Y. Kim Y.O. Park B.G. Pinto M.R. Rafferty C.S. Tennant D.M. Westerwick E.H. Chin G.M. Morris M.D. Early K. Mulgrew P. Mansfield W.M. Watts R.K. Voshchenkov A.M. Bokor J. Swartz R.G. Ourmazd A. 《Electron Device Letters, IEEE》1992,13(5):256-258
The authors report the implementation of deep-submicrometer Si MOSFETs that at room temperature have a unity-current-gain cutoff frequency (f T) of 89 GHz, for a drain-to-source bias of 1.5 V, a gate-to-source bias of 1 V, a gate oxide thickness of 40 Å, and a channel length of 0.15 μm. The fabrication procedure is mostly conventional, except for the e-beam defined gates. The speed performance is achieved through an intrinsic transit time of only 1.8 ps across the active device region 相似文献
107.
Sang-Hoon Lee Dae Hwan Kim Kyung Rok Kim Jong Duk Lee Byung-Gook Park Young-Jin Gu Gi-Young Yang Jeong-Taek Kong 《Nanotechnology, IEEE Transactions on》2002,1(4):226-232
A practical model for a single-electron transistor (SET) was developed based on the physical phenomena in realistic Si SETs, and implemented into a conventional circuit simulator. In the proposed model, the SET current calculated by the analytic model is combined with the parasitic MOSFET characteristics, which have been observed in many recently reported SETs formed on Si nanostructures. The SPICE simulation results were compared with the measured characteristics of the Si SETs. In terms of the bias, temperature, and size dependence of the realistic SET characteristics, an extensive comparison leads to good agreement within a reasonable level of accuracy. This result is noticeable in that a single set of model parameters was used, while considering divergent physical phenomena such as the parasitic MOSFET, the Coulomb oscillation phase shift, and the tunneling resistance modulated by the gate bias. When compared to the measured data, the accuracy of the voltage transfer characteristics of a single-electron inverter obtained from the SPICE simulation was within 15%. This new SPICE model can be applied to estimating the realistic performance of a CMOS/SET hybrid circuit or various SET logic architectures. 相似文献
108.
109.
Optimal observer-based wheelbase preview regulator problem is investigated for active vehicle suspension systems. It is shown
that the problem reduces to the classical linear quadratic Gaussian problem, whose solution is well defined, by augmenting
dynamics of system and road inputs. The resulting optimal controller is in the form of augmented state feedback controller
and this augmented state is estimated by Kalman-Bucy filter using dynamics of the augmented system. Numerical examples of
a half car model are given to verify the performance improvement achievable with the proposed controller. 相似文献
110.
Topographically distinct populations of radial glial cells in the diencephalon and mesencephalon of neonatal rats and hamsters were transcellularly labeled with wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and with the lipophilic tracer DiI. A comparison of the histological distribution of the two tracers is suggestive of two different mechanisms of transcellular labeling. Intraocular injections of WGA-HRP resulted in the uptake of exogenously applied WGA-HRP by retinal ganglion cells, followed by anterograde axonal transport and exocytosis within the optic target nuclei. In addition to the transneuronal labeling, which is typical of such injections, we observed the transcellular labeling of the processes and somata of radial glial cells that were topographically associated with the terminal fields of the labeled axons. Similar transcellular labeling of radial glial cells associated with the axon terminal fields of the colliculogeniculate projection to the medial geniculate nucleus was observed following injections of WGA-HRP in the inferior colliculus. The transcellular labeling within the radial glial cells was discontinuous and somatopetally concentrated, indicating the existence of a retrograde active transport mechanism within the radial glial processes subsequent to its uptake following release of tracer from axons. This type of labeling can be referred to as transcellular retrograde glioplasmic transport. In contrast, DiI was used as a tracer through its capacity to diffuse within the plasmalemma. Topographically distinct populations of radial glial cells were transcellularly labeled following placements of DiI in the retina, inferior colliculus, or dorsal thalamus of fixed brains. The radial processes of labeled radial glial cells consistently extended into regions that also contained labeled axons. It is likely that the transcellular radial glial labeling with DiI occurred via transmembranous diffusion. These data indicate that a close structural and functional relation exists between axons and glial cells in the developing brain. 相似文献