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71.
J Gérain D Liénard S Pampallona M Baumgartner C Rüegg WA Buurman A Eggermont F Lejeune 《Canadian Metallurgical Quarterly》1997,9(12):1034-1042
Isolated limb perfusion (ILP) with high dose tumour necrosis factor (TNF), interferon gamma and melphalan (TIM) is an efficient treatment for patients with regionally advanced melanoma and sarcoma. In 44 patients, we determined the kinetics of soluble TNF receptors (sTNF-RI and RII) plasma concentrations, and correlated them with systemic TNF and interleukin 6 (IL-6) levels and shock. Seven patients treated conventionally by ILP without cytokine served as controls. Elevated levels of both sTNF-Rs were observed within 30 min after beginning of the TIM-ILP. A first peak of sTNF-Rs levels was observed 3 h after ILP and was followed by a rapid decrease reaching a nadir at 12-14 h post ILP. This first peak was followed by a second, long-lasting elevation of both sTNF-Rs levels persisting for 4 to 5 days after TIM-ILP. Patients treated by ILP without TNF/interferon gamma (IFN-gamma) had no detectable increase in either sTNF-Rs or in circulating TNF, demonstrating that the release of TNF-Rs was dependent upon the administration of TNF/IFN-gamma. High plasma levels of TNF and IL-6 were observed in patients that had more than 5% leakage during the TIM-ILP, but no significant correlation between TNF levels and the peak values of both sTNF-Rs was observed. The levels of TNF and IL-6 were, however, significantly related to each other. TNF systemic levels, but not sTNF-Rs concentrations, correlated significantly with the severity of the shock observed after TIM-ILP. Patients in which sTNF-RII concentration was in excess over circulating TNF, had no shock or grade I shock only, suggesting that sTNF-RII may play a protective, although limited, role in inhibiting activity of circulating TNF. 相似文献
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The role of the blood-brain barrier transporter PTS-1 in regulating concentrations of methionine enkephalin in blood and brain 总被引:1,自引:0,他引:1
The entrainment of the circadian rhythm of locomotor activity was studied in the field mouse Mus booduga in order to examine the relationship between the free-running period (tau) and minimum tolerable light pulse interval of the skeleton photoperiods. The animals were entrained under three different light/dark (LD) schedules, each out of phase with the other. They were then subjected to various skeleton photoperiods created by two repeated light pulses (LPs) interrupting darkness. Animals that selected the shorter interval between the LPs as their "subjective night" had significantly shorter tau (23.13 +/- 0.38 h) as compared to those that selected the longer dark interval as subjective night (tau = 23.87 +/- 0.18 h). When the longer dark interval was 12 h, animals selecting that interval as their subjective night included both long-tau and short-tau individuals. When both intervals of darkness were of equal duration, no difference in the selection of subjective night was seen between short and long-tau animals. When the "dusk" LP for the animals that selected the longer dark interval as subjective night was advanced by 2 h to create a new skeleton photoperiod, the number of transient cycles appearing before steady-state entrainment was found to depend on the duration of the photoperiods. When the night defined by the two LPs was reduced below 6h, a dramatic "phase jump" in the activity rhythm was observed, and the initial phase relationship was restored after a relaxation in the night duration. We observed considerable interindividual variation in the "minimum tolerable light pulse interval of skeleton photoperiods," which we suggest may be due to the observed variation in tau among individuals. 相似文献
76.
Gangqiang Yu Nicolás F. Gajardo-Parra Min Chen Biaohua Chen Gabriele Sadowski Christoph Held 《American Institute of Chemical Engineers》2023,69(5):e18053
The suitability of phenyl-based deep eutectic solvents (DESs) as absorbents for toluene absorption was investigated by means of thermodynamic modeling and molecular dynamics (MD). The thermodynamic models perturbed-chain statistical associating fluid theory (PC-SAFT) and conductor-like screening model for real solvents (COSMO-RS) were used to predict the vapor–liquid equilibrium of DES–toluene systems. PC-SAFT yielded quantitative results even without using any binary fitting parameters. Among the five DESs studied in this work, [TEBAC][PhOH] consisting of triethyl benzyl ammonium chloride (TEBAC) and phenol (PhOH), was considered as the most suitable absorbent. Systems with [TEBAC][PhOH] had lowest equilibrium pressures of the considered DES–toluene mixtures, the best thermodynamic characteristics (i.e., Henry's law constant, excess enthalpy, Gibbs free energy of solvation of toluene), and the highest self-diffusion coefficient of toluene. The molecular-level mechanism was explored by MD simulations, indicating that [TEBAC][PhOH] has the strongest interaction of DES–toluene compared to the other DESs under study. This work provides guidance to rationally design novel DESs for efficient aromatic volatile organic compounds absorption. 相似文献
77.
Manfred Held 《Propellants, Explosives, Pyrotechnics》1991,16(1):21-26
An analysis of the secondary fragments emerging from a target plate has shown that their mass distribution fits excellently to a formula established earlier by the author. This applies equally well to the secondary fragments of an explosive-formed fragment from a multi-P warhead, to those from the warhead's structural casing. and even to the fragments from the target plate itself, as well as to the sum of all of these 3 types of fragements. The correlation coefficient for the two constant parameters governing this formula (namely, the scaling factor B and the form factor λ) is always better than 0.99, when an optimum total mass Mo is southt and inserted, and when the first, large fragements are not included in the consideration, which means when one or two measured points are negiected. For secondary fragements, the form factor λ in the mass distribution is close to 1/2 = 0.5, whereas for the natural fragments of HE projectiles it is in the order of 2/3. namely, from 0.6 to 0.8. 相似文献
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79.
Manfred Held 《Propellants, Explosives, Pyrotechnics》1989,14(4):153-161
All high explosives, at least the ones used in military applications, have a specific minimum detonation radius, Rmin with which the detonation can change its direction through 90° or 180°. It is to be emphasized that this applies not only to thc so-called insensitive high explosives, but the sensitive explosives of course have smaller radii than the insensitive ones. The corner-turning distance, As, determined in the radial test, also corresponds to the minimum radius, Rmin for the detonation wave to invert its direction through 180°. The radial test is a simple method, with regard to both design and analysis, that is suitable for determining the 90°-distance, or the minimum detonation radius, Rmin. 相似文献
80.
假定股票价格过程服从分数跳-扩散过程,利率满足分数Vasicek利率模型,利用分数跳-扩散过程理论以及保险精算方法,讨论了创新重置期权的定价问题,获得了创新重置看涨期权定价公式,推广了关于创新重置期权定价的相关结果. 相似文献