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排序方式: 共有10000条查询结果,搜索用时 9 毫秒
951.
Blair J.D. Correale A. Jr. Cranford H.C. Dombrowski D.A. Erdelyi C.K. Hoffman C.R. Lamphere J.L. Lang K.W. Lee J.K. Mullen J.M. Norman V.R. Oakland S.F. 《Solid-State Circuits, IEEE Journal of》1989,24(6):1647-1655
The authors describe a 9.02×9.02-mm chip built in 1-μm CMOS with two levels of metal and an additional mask level for fabricating capacitors. It contains both analog and digital circuits and has provisions for self-test. The function includes the transmitter, receiver, protocol handler, an microprocessor, as well as interfaces for RAM/ROM storage, IBM PC bus, IBM PS/2 bus, IBM 3174 bus, and Motorola 68000 bus. The physical design terrains are formed by 24K circuits of standard cell gates, a 10K-circuit equivalent hand-honed custom microprocessor, and an analog macro. The chip operates from a single 5-V supply, and the power consumption is 0.8 W nominal at 16 Mb/s. The chip can also be operated at 4 Mb/s 相似文献
952.
V A Meshcheriakova M A Samsonov I A Frolova O A Plotnikova G R Pokrovskaia 《Voprosy pitaniia》1985,(3):9-13
A study was made of the effect of wheat bran contained by the antisclerotic diet on lipid metabolism in patients with chronic coronary heart disease. Eighty-two patients (males) aged 36-59 years with a history of myocardial infarction of 1- to 15 year-standing were entered into the study. It was ascertained that inclusion into the antisclerotic diet of wheat bran in an amount of 70-80 g does not exert any hypolipidemic action. No elevation of the serum alpha-cholesterol content was noticed either. The augmentation of the cholic acid concentration together with a reduction in the cholesterol content in the hepatic bile attests to its reduced lithogenicity. 相似文献
953.
D G Kindack A MacIntosh M Lebelle G Carignan S Sved 《Food Additives & Contaminants》1991,8(6):737-748
During surveillance of hog carcasses from Manitoba for antibiotic residues by the Health of Animals Laboratory, Agriculture Canada, Saskatoon, an unknown substance was found which produced tetracycline-like results with the methods used. This same substance was found in an implicated swine feed premix. Using various HPLC systems and columns, UV spectroscopy, reverse-phase TLC, and mass spectrometry, the substance was isolated from the feed premix, and identified as lumichrome, a photodegradation product of riboflavin. Traces of the same substance were found in riboflavin standard. Analysis of swine kidney, previously found to contain the unknown, showed the same substance was present at a level of about 1 ppm. 相似文献
954.
955.
A. O. Skomorokhov V. N. Kutinsky M. T. Slepov 《Pattern Recognition and Image Analysis》2006,16(1):85-88
The paper describes a few modifications of the classification tree construction algorithm that have proved to be useful for
solving tasks of noise spectra processing with reference to NPP diagnostics.
The article was translated by the authors. 相似文献
956.
The effect of coherency loss on the development of precipitate size distribution under cascade-producing irradiation is considered. The nucleation of coherent precipitates, their growth followed by coherency loss and cascade-induced dissolution of large incoherent precipitates can occur simultaneously resulting in formation of a quasi-stationary size distribution of semicoherent precipitates. To describe this process we consider co-evolution of a mixed population of coherent, semicoherent and incoherent precipitates. Mathematically, the problem is formulated as a set of discrete rate equations of nucleation kinetics (the Master equation approach) which is also used for later stages of evolution. To solve the corresponding large set of equations (typically, more than 105 equations) an efficient numerical method is developed. The simulation results obtained for material parameters and irradiation conditions typical for nuclear reactors show that the coherency loss affects considerably evolution of the precipitate population. Under certain irradiation conditions, both in solution-annealed alloys and in aged ones, the mean precipitate size and the number density during prolonged irradiation tend to steady state values, whereas the size distribution function of large precipitates narrows. The width of the quasi-stationary size distribution is controlled by cascade parameters. It was found that the asymptotic quasi-stationary state of the precipitate population may depend on initial state of the alloy. 相似文献
957.
I. Ya. Braslavskii A. V. Kostylev D. V. Mezeusheva 《Russian Electrical Engineering》2007,78(11):603-606
The use of prognostic control methods in the digital systems controlling asynchronous electric drives are considered. The methodology for synthesizing predictors on the basis of neural networks is explained. An example of the synthesis of a numeral predictor for a closed control loop is considered. 相似文献
958.
959.
V. N. Serebryany A. Ya. Kochubei S. F. Kurtasov K. E. Mel’nikov 《Russian Metallurgy (Metally)》2007,(1):73-78
Quantitative texture analysis is used to study texture formation in an MA2-1 magnesium alloy subjected to axisymmetric upsetting at temperatures of 250–450°C and strain rates of 10?4–100 ?1. The deformed structure is examined by optical microscopy, and the results obtained are used to plot the structural-state diagram of the alloy after 50% upsetting. The experimental textures are compared with the textures calculated in terms of a thermoactivation model. 相似文献
960.
Motion field and optical flow: qualitative properties 总被引:7,自引:0,他引:7
Verri A. Poggio T. 《IEEE transactions on pattern analysis and machine intelligence》1989,11(5):490-498
It is shown that the motion field the 2-D vector field which is the perspective projection on the image plane of the 3-D velocity field of a moving scene, and the optical flow, defined as the estimate of the motion field which can be derived from the first-order variation of the image brightness pattern, are in general different, unless special conditions are satisfied. Therefore, dense optical flow is often ill-suited for computing structure from motion and for reconstructing the 3-D velocity field by algorithms which require a locally accurate estimate of the motion field. A different use of the optical flow is suggested. It is shown that the (smoothed) optical flow and the motion field can be interpreted as vector fields tangent to flows of planar dynamical systems. Stable qualitative properties of the motion field, which give useful informations about the 3-D velocity field and the 3-D structure of the scene, usually can be obtained from the optical flow. The idea is supported by results from the theory of structural stability of dynamical systems 相似文献