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111.
112.
The feasibility of using a potassium ferioxalate actinometer as a photochemical pyranometer was studied. The preparation, exposure, and spectrophotometric analysis of the pyranometer cell are described. By calibrating it against a Yellot Mark IV solameter, linear correlations were obtained with respect to total insolation and time of exposure. The spectral response, the quantum yields at different wavelengths, the mechanism of photochemical reaction, and the conversion factor for converting the absorption reading into cal/cm2/min are discussed. The advantages of the new pyranometer are its low cost, simplicity of operation and calibration, high sensitivity, and high tolerance to field conditions. It is useful for mapping solar intensity distribution over a wide area. 相似文献
113.
Demonstrated the importance of the direct hippocampo-anterior thalamic component of the postcommissural fornix in the control of general locomotion and active avoidance; 40 adult male Sprague-Dawley rats were Ss in 3 experiments. Transection of anterior thalamic afferents from the hippocampal formation (subicular cortex), at the point where they exit from the fornix posterior to the septum, enhanced bidirectional active avoidance acquisition and increased general activity. This transection may also interrupt fibers to or from other thalamic nuclei and the anterior septum. However, destruction of connections of the anterior septum with the hippocampus, habenula, and thalamus by transection in the coronal plane anterior to the descending fornix columns, without damage to the subiculothalamic fibers, increased general activity levels without affecting active avoidance behavior. The activity increase in this case resembled that seen after septal lesions rather than that seen after hippocampal lesions. Thus, destruction of a single fornix component contributing afferents to the anterior thalamic nuclei reproduces at least part of the hippocampal syndrome. This suggests that these fibers contribute significantly to the control of these behaviors and may mediate active avoidance changes resulting from hippocampal and fornix damage. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
Ernest Rabinowicz 《Wear》1977,42(1):149-156
A number of recent papers report the formation of spherical wear particles during sliding. In this paper a model is developed in which wear particles formed by adhesive wear processes are trapped in cavities in the sliding surfaces and become smoothed by burnishing processes. It is shown that the reported spherical particle diameters and lengths of sliding are consistent with this model. According to the model, spherical particles are only to be anticipated in slow uniaxial sliding, in fretting and within cracks of a material being fatigued. 相似文献
115.
The analytical electron microscope (AEM) was used to examine the microstructure of type 316LN stainless steel alloys which
had been annealed for 50 to 300 hours in the temperature range 600 to 700 °C. The M23C6 carbide chemistry and distribution are described as a function of heat treatment.X-ray spectroscopy in the AEM revealed significant
chromium depletion at grain boundaries in the vicinity of carbides for samples aged at 50 and 100 hours at 650 °C and 100
and 300 hours at 700 °C, with lower grain boundary chromium values observed at 650 °C than at 700 °C. The width of the chromium
depleted zone normal to the grain boundaries increased with increasing annealing time and/or temperature. Measurements of
chromium concentration along the grain boundaries away from a carbide were made after aging at 700 °C for 100 hours, and the
chromium level rose steadily until the bulk value was reached at a distance of ~3μm from the carbide. The width of the chromium
depleted zone normal to the boundaries in the same sample was an order of magnitude less. Some molybdenum depletion was also
found at the grain boundaries, and the Mo-depletion profiles were in form and extent similar to the chromium results. Simple
thermodynamic models were used to calculate the equilibrium value of chromium at the carbide-matrix interface, and the chromium
distribution along and normal to the grain boundaries. The results of these models agreed well with the AEM results, and the
agreement can be improved by considering the effect of electron probe configuration on the AEM measurements. The calculated
thermodynamic data and the AEM results were related to the corrosion behavior of the alloys. The occurrence of severe asymmetries
in some concentration profiles normal to the grain boundaries, which increased with increasing annealing temperature or time,
was shown to be due to boundary movement during the discontinuous precipitation of M23C6 carbides. 相似文献
116.
117.
The nature of the distinction between primary and secondary processes, as described by Freud, has relevancy for both a cognitive psycholoy and a psychology of motivation. Several issues arising from an examination of the 2 processes are examined. Possible empirical approaches to the basic problems are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Deborah Wang Ernest S. Kuh 《International Journal of Circuit Theory and Applications》1991,19(6):525-549
In this paper a number of new channel-routing algorithms are presented. the routing strategy is based on parallel bubble-sorting and river-routing techniques. an important concept introduced is the POTENTIAL function, which serves as a measure of the degree of difficulty of a particular channel-routing problem. Both non-Manhattan wires and overlapping wires are used. Although the methods are initially derived for two-layer routing with two-terminal nets only, extensions to multiterminal nets and three-layer routing have been made. Preliminary results indicate that in many instances the new algorithm outperforms the traditional approaches. 相似文献
119.
Jouriles Ernest N.; Norwood William D.; McDonald Renee; Vincent John P.; Mahoney Annette 《Canadian Metallurgical Quarterly》1996,10(2):223
Two studies examined whether physical marital violence and other forms of marital aggression (e.g., threats, throwing objects) correlate with children's behavior problems in families marked by recent spousal violence. Study 1 included 55 families seeking marital therapy. Study 2 included 199 families at battered women's shelters. In the marital therapy sample, both physical marital violence and other forms of marital aggression correlated positively with children's externalizing problems. In the women's shelter sample, physical violence and other forms of marital aggression correlated positively with children's externalizing and internalizing problems. After accounting for the frequency of physical marital violence, forms of marital aggression other than physical violence still related to children's externalizing problems in the marital therapy sample and to children's internalizing problems in the women's shelter sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
120.
Ernest W. Dewing 《Metallurgical and Materials Transactions B》1989,20(5):675-677
This paper assembles literature data, mainly vapor pressures and concentration-cell electromotive forces (emf's), from which
the variation of activity of NaF and A1F3 when a third substance is added to Na3AlF6 can be deduced. The necessary theory is derived. Where there is more than one source of information on a given substance,
the agreement is poor, showing imprecision in the experimental data. Substances are characterized by ∂ In aAlF
3/∂N3, whereN
3
is the molar fraction of the additive, and a value of -1 is neutral, since it corresponds to a dilution effect. Positive
values show acids; A1F3 itself has a value of +27.9, while NaF has a value of -27.9. BeF2 and MgF2 are strong acids with values of +11, CaF2 is a weak acid with a value of +2, and LiF, SrF2, BaF2, and 1/3(A12O3) are weak bases with values of -2 to -3. 相似文献