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41.
A new electrochemical heat pump using a combination of an electrolytic reaction at lower temperature to absorb low grade thermal energy and a thermochemical reaction at higher temperature to produce more efficient thermal energy is proposed. At a lower temperature, an endothermic reaction which cannot occur thermochemically proceeds with electrolysis. At a higher temperature, an exothermic reaction which is the reverse of the electrolysis reaction occurs thermochemically to produce high grade thermal energy. The water gas shift reaction, CO2(g) + H2(g) CO(g) + H2O(g), in molten carbonate is one possible candidate for the new electrochemical heat pump and can lead to an increase in the temperature of the thermal energy from 1100 to 1200K. A heat pump system using the shift reaction is also considered theoretically. 相似文献
42.
T. Kubo M. Ishihara N. Inabe H. Kumagai I. Tanihata K. Yoshida 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1992,70(1-4):309-319
A radioactive beam facility based on projectile fragmentation, RIPS, has been constructed at RIKEN to enable radioactive-beam experiments. The facility is characterized by the production of high-intensity beams and spin-polarized beams. Since the beginning of 1990, experiments on exotic nuclei have been extensively performed exploiting these useful features. The characteristics and the present status of the RIPS are described. 相似文献
43.
M Takahashi Y Hoshii H Kawano M Setoguchi T Gondo Y Yamashita K Nakayasu T Kamei T Ishihara 《Canadian Metallurgical Quarterly》1998,22(3):360-367
OBJECTIVE: To assess the association between high but nondiabetic blood glucose levels and the risk of death from all causes, coronary heart disease (CHD), cardiovascular disease, and neoplasms. RESEARCH DESIGN AND METHODS: We studied the 20-year mortality of non-diabetic, working men, age 44-55 years, in three European cohorts known as the Whitehall Study (n = 10,025), the Paris Prospective Study (n = 6,629), and the Helsinki Policeman Study (n = 631). These men were identified by their 2-h glucose levels following an oral glucose tolerance test and by the absence of a prior diagnosis of diabetes. As the protocol for the oral glucose tolerance test and methods for measuring glucose differed between studies, mortality was analyzed according to the percentiles of the 2-h and fasting glucose distributions, using the Cox's proportional hazards model. RESULTS: Men in the upper 20% of the 2-h glucose distributions and those in the upper 2.5% for fasting glucose had a significantly higher risk of all-cause mortality in comparison with men in the lower 80% of these distributions, with age-adjusted hazard ratios of 1.6 (95% CI 1.4-1.9) and 2.0 (1.6-2.6) for the upper 2.5%. For death from cardiovascular and CHD, men in the upper 2.5% of the 2-h and fasting glucose distributions were at higher risk, with age-adjusted hazard ratios for CHD of 1.8 (1.4-2.4) and 2.7 (1.7-4.4), respectively. CONCLUSIONS: If early intervention aimed at lowering blood glucose concentrations can be shown to reduce mortality, it may be justified to lower the levels of both 2-h and fasting glucose, which define diabetes. 相似文献
44.
45.
The letter reports a new apodisation of electrodes which provides surface-acoustic-wave filters capable of operation without apodisation loss and with sufficiently large stopband attenuation. The effectiveness of the apodisation was shown by experiments. 相似文献
46.
A single oral administration of conjugated linoleic acid enhanced energy metabolism in mice 总被引:1,自引:0,他引:1
We investigated the effect of a single oral administration of conjugated linoleic acid (CLA) on energy metabolism in mice.
Male Std ddY mice were orally administered CLA (5 mL/kg weight) or linoleic acid (5 mL/kg weight) (both solutions at concentrations
of 73.5%) as a control. Oxygen consumption was significantly greater in the CLA-administered mice than in the control mice.
Respiratory quotient was slightly lower in the CLA-administered mice than in the control mice. We calculated fat and carbohydrate
oxidation from oxygen consumption and respiratory quotient. Fat oxidation in the CLA-administered mice was significantly higher
than in the control mice, and there was no difference in carbohydrate oxidation. Serum concentrations of noradrenalin and
adrenalin in the CLA administered mice were significantly higher than in the control mice. These results suggested that CLA
enhanced sympathetic nervous activity and energy metabolism. 相似文献
47.
Kojic acid was glucosylated to kojic acid 5- and 7-O-beta-D-glucopyranosides by cultured cells of Eucalyptus perriniana. The glucosylation was also performed effectively by the enzymatic reaction system using membrane-associated UDP-glucosyltransferase from the cells with addition of UDP-glucose. The production of the 5-O-D-glucoside occurred exclusively prior to that of the 7-O-glucoside in both systems. In the same manner, daidzein was converted to daidzin (daidzein 7-O-beta-D-glucopyranoside) by the enzymatic system. Here, we propose methods for the structural modification of phytoestrogen-related substances by enzymatic beta-glucosylation. 相似文献
48.
A.J. McEvily S. Ishihara M. Endo H. Sakai H. Matsunaga 《International Journal of Fatigue》2007,29(12):2237-2245
Recent data on short fatigue crack growth in two cast and hot isostatically pressed (hipped) aluminum alloys obtained by Shyam, Allison and Jones have been analyzed in terms of a previously proposed one-parameter short crack model which includes consideration of elastic–plastic effects, the Kitagawa effect and the development of crack closure in the wake of a newly formed crack. The material constants obtained in a prior investigation of short crack growth behavior in a cast aluminum alloy tested under fully reversed loading were used as a basis for the present analysis. The predicted rates of fatigue crack propagation are in accord with the experimental results. In the discussion, aspects of the two-parameter approach presented by Shyam et al. are compared with those of the one-parameter method of analysis used herein. 相似文献
49.
The fast-discretization is known as an approximate but efficient technique for design and analysis of sampled-data systems. In this paper, we propose a fast-discretization-based design for sampled-data critical control systems. Supposing a tracking problem or a slow-changing disturbance rejection problem, we assume that an exogenous input is a persistent and/or transient input with bound on the rate of change. It is shown that the critical constraint for such exogenous inputs can be given in the form of the inequality constraint on the unit step response. The design parameters are determined by a numerical search method subject to this constraint. However, instead of evaluating it strictly, we check the corresponding constraint which is obtained from the fast-discretized system. Although this approach is approximate, it provides an efficient numerical procedure for a computer-aided design. To show the validity of the proposed method, an example of a multi-objective critical control system design is presented. 相似文献
50.
A biconical taper amplifier utilizing an Er3+-doped cladding fiber is discussed. A maximum gain of 0.6 dB in a 2.4-Gb/s optical transmission experiment was obtained with a taper about 40 mm long. This result shows the potential of a new structure for Er3+ -doped coupling and amplifying components 相似文献