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141.
Evaluation of rainfall networks using entropy: II. Application 总被引:2,自引:0,他引:2
This paper, the second in the series, applies the entropy approach to space and time evaluation of rainfall networks in Louisiana. The evaluation is made for five sampling intervals: daily, 2-day, weekly, monthly, and yearly, and for two separate seasons. In each case, the best combination of raingages is suggested and the lines of equal information (isoinformation contours) are constructed showing the areas of greater or less information transfer. The isoinformation lines are especially suitable in decisions concerning the expansion of the existing network or deleting the unnecessary raingages. 相似文献
142.
An earlier neural network analysis of processing of steel plates through hot rolling was subjected to a further refined analysis through some flexible neural networks that evolved using a multi‐objective predator‐prey genetic algorithm. The original data set expressing the Yield Strength and Ultimate Tensile Strength of the rolled slabs in terms of a total of 108 process variables were subjected to a systematic pruning through this evolutionary approach, till the nitrogen content of the steel emerged as the most significant input variable. A theoretical explanation is provided for this slightly unexpected result. 相似文献
143.
In the present paper, a modified self-flux technique has been successfully employed for the growth of pure and praseodymium
substituted (partially) large single crystals of high temperature superconducting Y1−x
Pr
x
Ba2Cu3O7−δ
(x = 0·0,0·2,0·4). Typical sizes of the platy and bulky crystals of pure YBCO(123) material are ≈ 2 × 2 × 0·1 mm3 and 4 × 1 × 1 mm3, respectively. In case of Pr-substitution, the typical sizes of platy and bulky crystals of Y0·8Pr0·2Ba2Cu3O7−δ
and Y0·6Pr0·4Ba2Cu3O7−δ
materials are ≈ 2 × 3 × 0·1 mm3 and 5 × 1 × 1 mm3 and ≈ 1 × 1·5 × 0·1 mm3 and 7 × 0·2 × 0·1 mm3, respectively. The morphology and growth habit of the as-grown single crystals and the critical transition temperature (T
c) of the oxygenated crystals were found to depend on the Pr-content.
Paper presented at the poster session of MRSI AGM VI, Kharagpur, 1995 相似文献
144.
Alan Royce Jiwaji Suryawanshi Udayan Shah Krishna Vishnupad 《Drug development and industrial pharmacy》1996,22(9):917-924
A melt granulation process has been investigated (1, 2) which efficiently agglomerates pharmaceutical powders for use in both immediate- and sustained-release solid dosage forms. The process utilizes materials that are effective as granulating fluids when they are in the molten state. Cooling of the agglomerated powders and the resultant solidification of the molten materials completes the granulation process. Both the molten agglomeration and cooling solidification were accomplished in a high shear Collette Gral mixer equipped with a jacketed bowl. Hence, the melt granulation process replaces the conventional granulation and drying operations which use water or alcohol solutions. The melt granulation process has been investigated using immediate- and sustained-release TAVIST® (clemastine fumarate USP) tablet formulations. The TAVIST granulations have been characterized by power consumption monitoring, measurement of the granulation particle size distribution, bulk and tapped density determinations, and loss-on-drying measurements. Scale-up of the melt granulation process for the sustained release TAVIST tablet formulation was judged successful based on a comparison of the hardness, friability, weight uniformity during compression, disintegration time, and dissolution rate data obtained at different manufacturing scales. 相似文献
145.
146.
In life testing, the failure-time distributions are often specified by choosing an appropriate hazard-rate function. The class of life-time distribution characterized by a linear hazard-rate includes the one-parameter exponential and Rayleigh distributions. Usually the parameters of the linear hazard-rate model are estimated by the method of least squares. This work is concerned with Bayes estimation of the two-parameters from a type-2 censored sample. Monte Carlo simulation is used to compare the Bayes risk of the regression estimator with the minimum Bayes risk. Discrete mixtures of decreasing failure rate distributions are known to have decreasing failure rates. The authors prove that the result holds for continuous mixtures as well 相似文献
147.
V. K. Singh J. K. Singh A. Kumar 《Bulletin of Engineering Geology and the Environment》2005,64(3):301-306
The study was undertaken to determine the optimal overall slope angle of a lead–zinc mine, which could extend down to a depth
of 170 m. Detailed geotechnical investigations were conducted, including geotechnical mapping of existing benches to establish
the geometrical and mechanical properties of the discontinuities, the drilling of eight boreholes and the establishment of
the physico-mechanical properties of the intact rock. Based on these data, limit equilibrium and numerical simulation techniques
were applied to assess the stability of the slopes and determine an optimal slope angle. It was concluded that the overall
foot-wall and hanging-wall slopes should be 42 and 48° respectively.
相似文献
148.
Madan G. Sood Jagjit Singh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):11-13
Cladosporium herbarum grown as a surface culture in a chemically defined medium of sucrose and inorganic salts gave a high yield of fat (29.2%). The component acids of this fat have been found to be palmitic (34.2%); oleic (15.9%); linoleic (34.2%) and linolenic (15.7%). The combined proportion of linoleic and linolenic acids being about 50 per cent, the fat will be of great value for the manufacture of oil-modified resins as the films produced by such resins do not become yellow with age. 相似文献
149.
150.
Yogesh Singh Chauhan Renaud Gillon Benoit Bakeroot Francois Krummenacher Michel Declercq Adrian Mihai Ionescu 《Solid-state electronics》2007,51(11-12):1581
An EKV-based high voltage MOSFET model is presented. The intrinsic channel model is derived based on the charge based EKV-formalism. An improved mobility model is used for the modeling of the intrinsic channel to improve the DC characteristics. The model uses second order dependence on the gate bias and an extra parameter for the smoothening of the saturation voltage of the intrinsic drain. An improved drift model [Chauhan YS, Anghel C, Krummenacher F, Ionescu AM, Declercq M, Gillon R, et al. A highly scalable high voltage MOSFET model. In: IEEE European solid-state device research conference (ESSDERC), September 2006. p. 270–3; Chauhan YS, Anghel C, Krummenacher F, Maier C, Gillon R, Bakeroot B, et al. Scalable general high voltage MOSFET model including quasi-saturation and self-heating effect. Solid State Electron 2006;50(11–12):1801–13] is used for the modeling of the drift region, which gives smoother transition on output characteristics and also models well the quasi-saturation region of high voltage MOSFETs. First, the model is validated on the numerical device simulation of the VDMOS transistor and then, on the measured characteristics of the SOI-LDMOS transistor. The accuracy of the model is better than our previous model [Chauhan YS, Anghel C, Krummenacher F, Maier C, Gillon R, Bakeroot B, et al. Scalable general high voltage MOSFET model including quasi-saturation and self-heating effect. Solid State Electron 2006;50(11–12):1801–13] especially in the quasi-saturation region of output characteristics. 相似文献