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1.
Number entry is a ubiquitous activity and is often performed in safety- and mission-critical procedures, such as healthcare, science, finance, aviation and in many other areas. We show that Monte Carlo methods can quickly and easily compare the reliability of different number entry systems. A surprising finding is that many common, widely used systems are defective, and induce unnecessary human error. We show that Monte Carlo methods enable designers to explore the implications of normal and unexpected operator behaviour, and to design systems to be more resilient to use error. We demonstrate novel designs with improved resilience, implying that the common problems identified and the errors they induce are avoidable. 相似文献
2.
Mengting Ma Zijun Li Feng Yang Huaixiang Wu Wuyang Huang Zhongquan Sui Harold Corke 《International Journal of Food Science & Technology》2021,56(7):3607-3617
Waxy, normal and high-amylose maize starches were subjected to heat-moisture treatment (HMT) and then added to wheat flour (WF) in different ratios (1%, 5% and 10%). The properties of blends and their cooked noodles were studied to investigate the effects of HMT starches. The incorporation of HMT starch in WF led to an increase in swelling power, peak viscosity and breakdown and to a decrease in setback, thus inhibiting retrogradation, hence enhancing resultant noodle softness. Compared to the same addition ratio of native starch to WF, HMT starch led to higher tensile strength and extensibility in resultant noodles. WF with added HMT starch had higher resistant starch than with native starch. This study showed that addition of HMT maize starch has potential to bring nutritional benefits. However, it is necessary to select the proper blending ratio and amylose content of starch to add, in consideration of its effect on noodle quality. 相似文献
3.
Harold S. Olcott 《Journal of the American Oil Chemists' Society》1948,25(4):125-127
Summary The toxic factor in cottonseed can be nullified by three apparently unrelated mechanisms: oxidation, combination with soluble
iron salts, and destruction by steam autoclaving. Oxidation is of minor importance except where the toxic factor has first
been extracted with ethyl ether and is present in the diet in solution in oil. Detoxication with soluble iron salts is demonstrable
even when the iron is administered in the drinking water. Ball-milled petroleum ether-extracted cottonseed meal can be detoxified
by autoclaving under conditions which are not effective for the original meal.
These results were obtained from feeding tests with rats.
This work was done during the tenure of the Cotton Research Foundation's Multiple Fellowship at Mellon Institute, Pittsburgh,
Pa. Presented in part before the American Society of Biological Chemists, New Orleans, March, 1940 (J. Biol. Chem.,133, lxxii (1940). 相似文献
4.
Summary A non-reducing disaccharide has been isolated from the kernels of tung (Aleurites fordi Hemsl.) and identified as sucrose. 相似文献
5.
Techniques for improving the reliability and maintainability of both nonrepairable and repairable items can be suggested by failure data analysis. It is shown that a given set of failure numbers leads to very different improvement strategies when the numbers are the times-between-successive-failures of one or more repairable items, rather than the times-to-failure of nonrepairable items. Since this should have been obvious more than 50 years ago, at the onset of formal reliability engineering activities, several reasons are proffered for the widespread and protracted misinterpretation of even the most basic—and simple!—conceptual and practical differences between nonrepairable and repairable items. 相似文献
6.
Uses principles of latent trait theory to derive conditions under which mean differences on an observed variable are indicative of mean differences on an underlying construct, focusing on the logistic curve as a model for describing the relation between the observed variable and construct. In this situation, and with normally distributed scores on the construct, a t test comparing groups on the observed variable produces correct inferences at the construct level only if group variances on the construct are homogeneous or the difficulty level of the test equals the mean ability level of the examinees. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
B Conrad E Weidmann G Trucco WA Rudert R Behboo C Ricordi H Rodriquez-Rilo D Finegold M Trucco 《Canadian Metallurgical Quarterly》1994,371(6495):351-355
Insulin-dependent diabetes mellitus (IDDM) is a T-cell-mediated autoimmune disease whose onset is believed to be triggered by unknown environmental factors acting on a predisposing genetic background. Islet-infiltrating T (IIT) cells from two IDDM patients, who had died at the onset of the disease from brain swelling as a complication of ketoacidosis, were analysed. The results provided evidence for the involvement of a pancreatic islet cell membrane-bound superantigen as a diabetes aetiopathogenetic factor. There was a selective expansion of a T-cell receptor (TCR) variable segment of the beta-chain (V beta 7) in these IIT cells in association with unselected V alpha-chain segments; extensive junctional diversity of the TCR V beta 7 chains; and evidence of positive selection, after exposure to diabetic islet cell membrane preparations, of V beta 7+ T-cell clones among peripheral blood lymphocytes from non-diabetic individuals. 相似文献
8.
Harold E. Kautz 《Research in Nondestructive Evaluation》1992,4(3):151-164
Lamb waves can be produced and detected in ceramic matrix composites (CMC) and metal matrix composites (MMC) plates using the acousto-ultrasonic configuration employing broadband transducers. Experimental dispersion curves of lowest symmetric and lowest antisymmetric modes behave in a manner analogous to the graphite/polymer theoretical curves. In this study a basis has been established for analyzing Lamb wave velocities for characterizing composite plates. Lamb wave dispersion curves and group velocities were correlated with variations in axial stiffness and shear stiffness in MMC and CMC. For CMCs, interfacial shear strength was also correlated with the first antisymmetric Lamb mode. 相似文献
9.
The energy interaction curves of a number of diatomic and polyatomic dication systems were calculated in order to study their energy-trapping properties. Generally, the ab initio complete active space multiconfiguration self-consistent field method was used in an extended valence + polarization basis set, with compact effective potentials replacing the core electrons. The diatomic dications include all ten possible binary combinations of oxygen, sulphur, selenium, and tellurium. O22+ shows the largest exothermicity, measured from equilibrium to the monocation combination asymptote, and highest barrier to dissociation. The calculated equilibrium bond length and harmonic vibrational frequency agree very well with experiment. The O22+, SO2+, SeO2+, and TeO2+ series show progressively decreasing exothermicities but similar barrier heights. The non-oxides, in contrast, show similar exothermicities but decreasing barriers with increasing size of the atom constituents. These trends are interpreted in terms of both valence bond curve-crossing and molecular orbital bonding models. The ozone dication, O32+, is found to have a number of low-lying singlet and triplet stationary state structures spanning near-linear to D3h2+ symmetries. Although the calculated exothermicity is even larger than for O22+, the barrier to O2+ + O+ dissociation is predicted to be low in each case. O22+ surrounded by six argon atoms to model an isolating environment shows increased equilibrium O–O bond length, decreased exothermicity, and increased barrier to dissociation, relative to the bare dication. O22+ flanked at each end by a perpendicularly oriented H2 molecule in a staggered conformation is obstructed from direct conversion to the water dimer dication by a high barrier. However, [(H2O)2]2+ dissociates smoothly from equilibrium to two water monocations with a large exothermicity but a small barrier. 相似文献
10.