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排序方式: 共有816条查询结果,搜索用时 15 毫秒
91.
Yasutaka Ohmachi Hiroshi Kawamura Akinori Tani Hajime Yoneda 《Computer-Aided Civil and Infrastructure Engineering》1996,11(4):219-238
Abstract: This paper proposes a method for formulation and quantification of human subjective evaluations and uncertain numerical values by using multiple hyperplanes based on the results of questionnaires distributed to structural designers that are composed of four questions about structural design and planning, i.e., ( Q 1) structural damage , ( Q 2) structural economy in a macroscopic sense , ( Q 3) structural safety, and ( Q 4) opening patterns in facade. In this paper, some hyperplanes in multidimensional spaces are used as a method to identify fuzzy relations (states) in intelligent fuzzy networks for seismic structural planning. A genetic algorithm is employed as a search method for optimal formulations and is proved to be very effective as a method for such an identification. 相似文献
92.
Keiji Nakajima Hajime Hasegawa Sakhob Khumkoa Shozo Mizoguchi 《Metallurgical and Materials Transactions B》2003,34(5):539-547
In order to elucidate the nature of the heterogeneous nucleation, a differential scanning calorimetry (DSC) thermal analysis
of pure Fe and Fe-Ni alloys (Ni content: 1.0 to 29.3 mass pct) containing TiN, Al2O3, and Ti2O3 was conducted. Then, special attention was paid to the difference in the phase of the primary crystal nucleated by the triggering
effect of a catalyst (nucleating agent). The solidification and transformation mode appearing during cooling in these alloys
is classified into three cases: F mode, FA mode, and A mode. The change of modes and the critical undercooling (ΔT) depend on the kind of catalyst used as well as the chemical composition (Ni content). In addition, in spite of the kind
of primary crystal, the value of ΔT is always small in the order of TiN, Al2O3, and Ti2O3. As a matter of fact, only TiN has a practical effect as a catalyst on the triggered nucleation of the primary crystal of
the δ phase. None of them has a practical effect on the nucleation of the primary crystal of the γ phase.
This article is based on a presentation given in the Mills Symposium entitled “Metals, Slags, Glasses: High Temperature Properties
& Phenomena,” which took place at The Institute of Materials in London, England, on August 22–23, 2002. 相似文献
93.
Katsutoshi Hori Michiharu Abe Hajime Unno 《Journal of Bioscience and Bioengineering》2009,108(4):319-324
Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) produced by various bacteria has been intensively investigated as a promising biodegradable plastic, but required a supply of an expensive precursor as a secondary carbon source for its production. In a previous study, we identified a new bacterial strain, Rhodococcus aetherivorans IAR1, which synthesizes PHBV from toluene without the supply of a precursor. Toluene is the volatile organic compound most abundantly emitted to the environment. In the present paper, we show that R. aetherivorans IAR1 produces triacylglycerols (TAGs) simultaneously with PHBV. Both PHBV and TAGs were synthesized before the nitrogen source is completely exhausted. The cellular content of PHBV reached 10% of cell dry weight (CDW) and its synthesis ceased even during intermittent supply of toluene. However, accumulation of TAGs continued during cultivation and their cellular content reached 24% of CDW at the end of cultivation. Cerulenin inhibited TAG production and increased PHBV cellular content up to 30% of CDW. The mole fraction of 3-hydroxyvalerate (3HV) in PHBV produced from toluene increased from 60% to 80% during its accumulation. Fatty acid compositions of TAGs produced from acetate and toluene were different. At the end of cultivation, the mole fraction of C17:0, one of odd-carbon number fatty acids, was 5% on toluene or 10% on acetate while the mole fraction of 3HV in PHBV from toluene was as high as that in PHBV from acetate, suggesting that a C5 intermediate of toluene degradation might directly become a precursor of 3HV whereas propionyl-CoA is required for the incorporation of C17:0 into TAGs. 相似文献
94.
A broadcast architecture network (Banet) suitable for distributed data processing is proposed. One feature of Banet is that the broadcast-within-a-group function is supported not only by the datalink level but by the transport or session-level network structure. The commitment control scheme is included in the network protocol. Design goals, physical structure and protocols are discussed. 相似文献
95.
This paper proposes a boundary-element method using spatial eigenmodes for electromgnetic field analysis. Mapping the computation model with rotational symmetries, reflective symmetries or rotational symmetries including reflective symmetries to a group of spatial eigenmodes, the equivalent reduced models are obtained. In the method, the applicability becomes wide because arbitrary external source terms can be chosen. Furthermore, in a model including asymmetry regions, a new method which can save the merit of the symmetries is proposed. Finally, the validity of the proposed method is proved by numerical simulations. 相似文献
96.
Kanichi Kamiya Tokiti Noda Michio Inagaki Hajime Saito 《Journal of Materials Science》1972,7(11):1244-1248
A soft carbon and a hard carbon which were prepared from Polyvinylchloride and phenolformaldehyde resin, respectively, both by carbonizing to about 700°C, were obtained as sintered cakes by heat-treatment up to about 1800°C under the quasihydrostatic pressure of 5 kbar. Preferred orientation of crystallites relative to the compressing direction in these cakes was determined by X-ray difraction technique by using the (004) or (002) diffraction line. The soft carbon showed remarkable preferred orientation of crystallites, but the degree of orientation was dependent only a little on heat-treatment temperature (HTT). At 1200°C under 5 kbar, the hard carbon gave a sintered cake which had no appreciably preferred orientation. The degree of preferred orientation of crystallites in the cake of the hard carbon greatly increased with the increase in HTT. The difference in the dependence of preferred orientation of crystallites in the soft and hard carbons on HTT was interpreted by referring to the texture of the original carbons. 相似文献
97.
Raman Spectroscopic Studies on the Formation Mechanism of Hydrous-Zirconia Fine Particles 总被引:1,自引:0,他引:1
Koji Matsui Hajime Suzuki Michiharu Ohgai Haruo Arashi 《Journal of the American Ceramic Society》1995,78(1):146-152
The Raman spectra of hydrous-zirconia fine particles produced by the hydrolysis of various ZrOCl2 solutions were investigated. The Raman spectra of hydrous zirconia synthesized at HCl concentrations below 1 mol/L were similar to those of monoclinic, crystalline ZrO2 ; those of hydrous zirconia synthesized at HCl concentrations greater than 1 mol/L showed a crystal structure change. The line width of the Raman bands increased with increasing H+ ion concentration. Analyzing the relationship between Raman band width and particle size revealed that the primary particle size of hydrous zirconia was controlled by the H+ and Cl− ions, because these ions interfered with the polymerization in a hydrolysis reaction. Based on the experimental results, the formation mechanism for primary particles of hydrous zirconia was determined. 相似文献
98.
99.
This paper considers a multiobjective reliability allocation problem for a series system with time-dependent reliability. The method determines the most preferable reliability allocation and preventive maintenance schedule. The problem is multiobjective nonlinear mixed-integer. The decision making procedure is based on interactive optimization and a nonlinear programming algorithm. The method is illustrated by a numerical example. 相似文献
100.
Shortest path, shortest spanning tree, complete graph, number of comparisons, expected complexity 相似文献