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101.
Using a parameter adjustment law, robust monotonic parameter error reduction is proved for a linear parameter estimation problem in which the signal is corrupted by the presence of nonparametric dynamical uncertainty. The nonparameterized dynamics are characterized by a known frequency-domain magnitude bound. A nonconservative bound on the finite-time energy of the nonparametric-dynamics output is constructed in real time. When the error single energy is small enough to be due to nonparametric dynamics alone, the parameter adjustment is shut off to avoid misadjustment. The approach is an extension of existing adaptive control error-dead-zone ideas to the case of frequency-domain bounded uncertainty 相似文献
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High pressure extraction of oil seed 总被引:4,自引:0,他引:4
For calculation of phase equilibria of the system seed oil/CO2, an equation of state published in the literature has been fitted to experimental data of that system. The results thus obtained
are of only limited use in designing a supercritical extraction process. The experimental investigation of the mass transfer
kinetics is much more significant. Mechanical processing of the oil seed’s cell wall structure has been shown to be of great
importance. The best specific yields were achieved with material that had been mechanically pre-deoiled and thereby broken
open. Yields are increased considerably by use of the gas mixture CO2/propane or other special gas mixtures or by the addition of refrigerants. However, the extraction times achieved in batch
operation, together with the mass product nature of oil seed, make a continuous supercritical extraction essential if operation
is to become economic relative to the conventional hexane extraction. To this end, the energetics of the process have been
calculated, and practical possibilities for continuous operation are discussed.
Presented at the International Symposium, “High Pressure Chemical Engineering,” Erlangen, in October 1984. 相似文献
104.
Exploring the Effects of Glycosylation and Etherification of the Side Chains of the Anticancer Drug Mitoxantrone 下载免费PDF全文
Pazit Shaul Kfir B. Steinbuch Eran Blacher Prof. Reuven Stein Dr. Micha Fridman 《ChemMedChem》2015,10(9):1528-1538
Herein we report the synthesis and biological evaluation of symmetric and asymmetric analogues of the DNA intercalating drug mitoxantrone (MTX) in which the side chains of the parent drug were modified through glycosylation or methyl etherification. Several analogues with glycosylated side chains exhibited higher DNA affinity than the parent MTX. The most potent in vitro cytotoxicity was observed for MTX analogue 8 (1,4‐dimethoxy‐5,8‐bis[2‐(2‐methoxyethylamino)ethylamino]anthracene‐9,10‐dione) with methoxy ether containing side chains. Treatment of melanoma‐bearing mice with MTX or analogue 8 decreased the intraperitoneal tumor burden relative to untreated mice; the effect of 8 was less pronounced than that of MTX. In vitro metabolism assays of MTX with rabbit liver S9 fraction gave rise to several metabolites; almost no metabolites were detected for MTX analogue 8 . The results presented indicate that derivatization of the MTX side chain primary hydroxy groups may result in a significant improvement in DNA affinity and lower susceptibility to the formation of potentially toxic metabolites. 相似文献
105.
Fluidisation is frequently accompanied by unwanted attrition of the bed material. This paper focuses on the mechanical aspects of fines creation by attrition in fluidised beds supported by multi-orifice distributor plates. The attrition rates of low-density porous glass particles were measured; these particles show abrasive wear behaviour rather than breakage. Positron emission particle tracking (PEPT) was used to follow particle motion in three dimensions within the fluidised bed. For a single orifice distributor with background fluidisation, the attrition rate increased exponentially with increasing orifice gas velocity. For a multi-orifice distributor, however, attrition rates were roughly proportional to excess gas velocity, except near to a critical ratio of particle to orifice diameter; as this ratio approached 2, attrition was observed to increase by an order of magnitude. A method is proposed for estimating attrition rates from a combination of small-scale experimental results and theoretical calculations of distributor jet entrainment rates. 相似文献
106.
ABSTRACT Recently a technique for monitoring and diagnosing mechanical problems, associated with rotating machines driven by electric motors, has been proposed and is now being offered by several commercial suppliers. This technique, known as “Motor Current Signature Analysis” or MCSA, seeks to apply much of the long experience in vibration signature analysis to the analysis of motor current in effect using the motor as a sensor akin to an acceleromeier This paper explores some of the history of the technique, presents several examples, and demonstrates a first order approach to the theory with associated cautions. 相似文献
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OBJECTIVE: In attempting to explain the familial predisposition to panic disorder, most studies have focused on the heritability of physiologic characteristics (e.g., CO2 sensitivity). A heretofore unexplored possibility is that a psychological characteristic that predisposes to panic-anxiety sensitivity-might be inherited. In this study, the authors examined the heritability of anxiety sensitivity through use of a twin group. METHOD: Scores on the Anxiety Sensitivity Index were examined in a group of 179 monozygotic and 158 dizygotic twin pairs. Biometrical model fitting was conducted through use of standard statistical methods. RESULTS: Broad heritability estimate of the Anxiety Sensitivity Index as a unifactorial construct was 45%. Additive genetic effects and unique environmental effects emerged as the primary influences on anxiety sensitivity. There was no evidence of genetic discontinuity between normal and extreme scores on the Anxiety Sensitivity Index. CONCLUSIONS: This study suggests that one psychological risk factor for the development of panic disorder-anxiety sensitivity-may have a heritable component. As such, anxiety sensitivity should be considered in future research on the heritability of panic disorder. 相似文献
110.
The highly active process stabilizer bis(2,4‐dicumylphenyl)pentaerythritol diphosphite (P1) was compared in a series of polyolefin formulations with tris(2,4‐di‐t‐butylphenyl) phosphite (P2). Because of its high activity, there was less polymer degradation during processing with P1 as compared to P2. As a result, improvements in color and other physical properties were observed for the polymers, not only during processing, but also after treatment with gamma radiation. 相似文献