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991.
A. Garton P. Z. Sturgeon D. J. Carlsson D. M. Wiles 《Journal of Materials Science》1978,13(10):2205-2210
The introduction of a 1000 Å scale corrugated structure, aligned perpendicular to the filament axis, into oriented semi-crystalline polymers on plasma etching is shown to result from restructuring of the partially etched surface and not, as has previously been proposed, to correspond to morphological detail in the unetched material. The detail exposed on plasma etching polypropylene is shown to vary extensively with the etching conditions used. The exposed surface is compared with those resulting from peeling and chromic acid etching. Plasma etching is, however, shown to be useful in exposing coarse morphological detail such as spherulites, and in providing a convenient route for rapidly stripping the polymeric sample. The restructured partially etched surface may then be removed easily by, for example, a brief chromic acid treatment, exposing the sample interior to microscopic examination.Issued as NRCC no. 16534 相似文献
992.
Swelling of steels and alloys irradiated in the BOR-60 reactor to a fluence of 1.1·1023 neutrons/cm2
N. P. Agapova V. S. Ageev I. N. Afrikanov N. I. Budylkin V. A. Krasnoselov E. G. Mironova V. D. Onufriev Z. E. Ostrovskii V. I. Prokhorov Yu. N. Sokurskii 《Atomic Energy》1978,45(6):1169-1175
Conclusions The structure created by preliminary treatment has a strong influence on the swelling, the nature of pore generation, the dislocation density, and the phase composition of 0Kh16N15M3B steel. The greatest reduction in swelling was produced by 20% cold deformation, which at a high dislocation density led to a sharp refinement of the pores and lamellar precipitations.The lamellar phases precipitated in steels of the Kh16N15 type during the irradiation after special alloying or preliminary treatment do not always determine the nature of the generation and growth of vacancy pores.At a temperature of 460 and 550°C the swelling of nickel is less by a factor of about 3, and the swelling of iron is less by a factor of about 10, than the swelling of austenized 0Kh16N15M3B steel.The least swelling was found in the Kh77TYu alloy (with 77% nickel), which before irradiation contained -phase pre-precipitations, whereas the swelling of alloys with 40 and 60% nickel is 100 times as great. From this it is clear that the nickel content is not the only factor determining the swelling.Journal version of a report delivered at the Conference on the Study of Reactor Materials (Alushta, 1978).Translated from Atomnaya Énergiya, Vol. 45, No. 6, pp. 433–439, December, 1978. 相似文献
993.
介绍球磨机的结构和工作机理,指出球磨机存在的问题,并对其轴封、轴头、进气口、吸料口等进行了技改,以提高设备的运行周期,满足生产需求。 相似文献
994.
G. P. Yasnikov L. G. Gal'perin Z. N. Kutyavin 《Journal of Engineering Physics and Thermophysics》1980,39(2):913-916
Using an operator representation of the effective diffusion coefficient we obtain a hyperbolic diffusion equation in a relaxational medium.Notation Fslot
return-flow slot area
- F
cross-sectional area of the bed in the vertical plane
- G*
instantaneous number of fine particles in the apparatus
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 39, No. 2, pp. 334–338, August, 1980. 相似文献
995.
Z Nováková-Veljaciková 《Canadian Metallurgical Quarterly》1980,43(2):139-144
To establish the basis of the interpretative method is congruous with finding a solid basis--epistemologically speaking--to the analytic theory. This basis would be the means to transform this theory into a real science with its necessary adecuation among method, act and object of knowledge. It is only from a scientific stand that the psychoanalytic theory will be able to face successfully the reductionisms that menace it, be it the biologist-naturalism with its explanations of the psychic phenomena by means of mechanisms and biologic models or be it the speculative ideologies with their nucleus of technical praxis which make it impossible for the social-factic sciences to become real sciences. We propose as interpretative method the union of two models: the teleologic one which makes possible the appearance of intelligible, contingent and variable explanations between an antecedent and a consequent on one side, and on the other, the analogic model with its two moments: the comparative and the symbolic one. These moments makes possible the comparison and the union between antecedent and consequent baring in mind the "natural" ambiguity of the subject-object in question. The principal objective of the method--as a regulative idea in the Kantian sense--would be the search of univocity as regards the choice of one and only one sense from all the possible senses that "explain" the motive relationship or motive-end relationship in order to make the interpretation scientific. This status of scientificity should obey the rules of explanation: that the interpretations be derived effectively from the presupposed theory, that they really explain what they claim to explain, that they are not contradictory or contrary in the same ontologic level. We postulate that the synthesis of the two mentioned models, the teleologic-explanative and the analogic one allows us to find a possibility to make clear the "dark" sense of the noun interpretation and in this way the factibility of speaking of an interpretative method that develops the real concrete object by producing the formal and abstract one--which for us is the behaviour of the subject--. In this way the interpretations come to be teleological explanations overdetermined by an analogical relationship. This means that they produce the formal and abstract object -the method--which is in itself an intelligible, continguent and variable relationship between an antecedent and a consequent permitting in this way the emergence of a symbolic comparison to explain the real concrete. The symbolic explanations and comparisons are strictly derived from the presupposed theory, the theoretical body of psychoanalysis. 相似文献
996.
E. L. Wolf D. M. Burnell Z. G. Khim R. J. Noer 《Journal of Low Temperature Physics》1981,44(1-2):89-118
An extensive superconducting electron tunneling study of Ta, using both a proximity method and an optimized conventional spectroscopy, is reported. The results for Ta confirm the electron-phonon origin of superconductivity in this element, and provide slightly improved superconducting parameters: =0.73 and ph
* = 0.11. The results from the PET and optimized conventional methods are in substantial agreement, although the proximity method appears to provide somewhat better resolution of structure in the Eliashberg function 2
F(E).Operated for the U.S. Department of Energy by Iowa State University under contract No. W-7405-Eng-82. This research was supported by the Director for Energy Research, Office of Basic Energy Sciences, WPAS-KC-02-02-02. 相似文献
997.
Moisture Diffusivity Data Compilation in Foodstuffs 总被引:12,自引:0,他引:12
A review of the recently reported moisture diffusivity experimental data in food materials is presented in this work. Values are classified and analysed statistically to reveal the influences of temperature and moisture content. Empirical models relating moisture diffusivity with the above variables, along with relevant graphs for various materials, are included. Other factors affecting moisture diffusivity prediction are also discussed. 相似文献
998.
Experimentally an attempt was made to demonstrate the effects of exogenous factors on the hormonally altered laryngeal mucosa of mice. Albany mice were divided into 4 groups of 8. In the first group of males, testosterone was injected daily; in the second group of males, no testosterone was given; in the third group of females with previously removed ovaries, testosterone was given daily; and, in the fourth group of females, no testosterone was given. All 4 groups were exposed to cigarette smoke for one hour daily for six weeks. Histopathological examination of the mucosa showed that the larynx can be considered a "target" organ for male hormones and that exogenous factors produce changes that lead to malignancy. 相似文献
999.
A 4-week UNESCO-sponsored mission to the Department of Architecture, Karadeniz Technical University in Eastern Turkey, gave an opportunity to apply ergonomics techniques to some aspects of that country's domestic washbasin design. The study was intended to provide experience in questionnaire design and administration, in the application of psycho-physical methods, and to highlight the importance of determining user characteristics and preferences with regard to the built environment. A field study elicited information on dimensions and positioning of existing wash-basins and ancillary equipment and the opinions of users as to the suitability of these features in relation to the activities performed. A laboratory study, using an adjustable rig permitting variation in the heights of basin, taps and mirror/shelf, followed. The data obtained on preferred heights of these items led to the conclusions that basin height should be increased to between 95 and 100 cm to satisfy the majority of users; tap height above the basin should be reduced to about 11 cm; the shelf and lower edge of a mirror sited above the basin should be 136 cm above the floor; and a clear space of 110 cm should be available between the front of the basin and a wall or other obstruction. Suggestions on other design aspects of the bathroom, resulting from the study, are discussed. 相似文献
1000.