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991.
"A group of ten non-psychotic psychiatric patients in the open ward of a general hospital was compared with seven medical patients without disabling psychiatric symptoms, with respect to the variability of their judgments of the autokinetic phenomenon… . The results indicated that neurotic Ss were consistently more variable than nonneurotic Ss in their judgments and were less affected by the group influence." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Design of steerable filters for feature detection using canny-like criteria   总被引:6,自引:0,他引:6  
We propose a general approach for the design of 2D feature detectors from a class of steerable functions based on the optimization of a Canny-like criterion. In contrast with previous computational designs, our approach is truly 2D and provides filters that have closed-form expressions. It also yields operators that have a better orientation selectivity than the classical gradient or Hessian-based detectors. We illustrate the method with the design of operators for edge and ridge detection. We present some experimental results that demonstrate the performance improvement of these new feature detectors. We propose computationally efficient local optimization algorithms for the estimation of feature orientation. We also introduce the notion of shape-adaptable feature detection and use it for the detection of image corners.  相似文献   
993.
Micro-Raman spectra of formalin-fixed oral squamous normal and carcinoma tissues, stored at room temperature for 2 months, have been recorded. Spectra were recorded both in the epithelial and subepithelial regions of the tissues. No noticeable spectral contamination due to formalin was observed. Very significant differences between spectra of normal epithelial and malignant epithelial samples were found. No such differences in spectra of subepithelial malignant and subepithelial normal samples could be observed. This study shows that spectra from the epithelial region changes drastically because of malignancy-induced biochemical changes in this region. Major differences between normal and malignant spectra seem to arise from the protein composition, conformational/structural changes, and possible increase in protein content in malignant epithelia. The differences between normal epithelial and subepithelial spectra, as expected, arise mainly from the collagen in subepithelial tissue. Principal component analysis of the combined sets of spectra-epithelial and subepithelial, normal and malignant- showed that very good discrimination can be achieved by Raman microspectroscopy. This study thus validates the suitability of formalin-fixed tissues for optical pathology in oral malignancy.  相似文献   
994.
Exposure atmospheres for a rodent inhalation toxicology study were generated from the exhaust of a 2000 Cummins ISB 5.9L diesel engine coupled to a dynamometer and operated on a slightly modified heavy-duty Federal Test Procedure cycle. Exposures were conducted to one clean air control and four diesel exhaust levels maintained at four different dilution rates (300:1, 100:1, 30:1, 10:1) that yielded particulate mass concentrations of 30, 100, 300, and 1000 microg/m3. Exposures at the four dilutions were characterized for particle mass, particle size distribution (reported elsewhere), detailed chemical speciation of gaseous, semivolatile, and particle-phase inorganic and organic compounds. Target analytes included metals, inorganic ions and gases, organic and elemental carbon, alkanes, alkenes, aromatic and aliphatic acids, aromatic hydrocarbons, polycyclic aromatic hydrocarbons (PAH), oxygenated PAH, nitrogenated PAH, isoprenoids, carbonyls, methoxyphenols, sugar derivatives, and sterols. The majority of the mass of material in the exposure atmospheres was gaseous nitrogen oxides and carbon monoxide, with lesser amounts of volatile organics and particle mass (PM) composed of carbon (approximately 90% of PM) and ions (approximately 10% of PM). Measured particle organic species accounted for about 10% of total organic particle mass and were mostly alkanes and aliphatic acids. Several of the components in the exposure atmosphere scaled in concentration with dilution but did not scale precisely with the dilution rate because of background from the rodents and scrubbed dilution air, interaction of animal derived emissions with diesel exhaust components, and day-to-day variability in the output of the engine. Rodent-derived ammonia reacted with exhaust to form secondary inorganic particles (at different rates dependent on dilution), and rodent respiration accounted for volatile organics (especially carbonyls and acids) in the same range as the diesel exhaust at the lowest exhaust exposure concentrations. Day-to-day variability in the engine output was implicated partially for differences of several components, including some of the particle bound organics. Though these observations have likely occurred in nearly all inhalation exposure atmospheres that contain complex mixtures of material, the speciations conducted here illustrate many of them for the first time.  相似文献   
995.
This study deals with the development of a silk coat around the growing larva of the Oriental hornet (Vespa orientalis). Prior to its metamorphosis into a pupa, the larva secretes a silk weave, which enwraps it completely. This silk coat is not uniform throughout, but rather varies along the extent of the larval body. First, it is possible to discern in the spun silk weave fibers whose thickness is approximately 10 microm; in which case such a fiber is actually a duplet of two individual fibers, each with its own silk coat and an inner fibril (core). Additionally, there are silk plaque-like surfaces of a greater diameter and of variable shape, depending on the contour that they cover. In the cap region, i.e. the region where the head of the larva (and later of the developing imago) is located, the fibers are quite numerous and arranged in many (up to 10) layers, while the silk plaques are small. For the remainder of its body, the pupating larva produces a silk sleeve in which there are few fibers with numerous plaques in between, occupying most of the area. The larval silk fibers proper are of fairly uniform diameter. Apart from the pupating larvae, the adult hornets also secrete a type of silk, which acts as a glue holding together the components of the larval cell wall and their sticky silk is of variable thickness, depending on the configuration of the cell. The temperature of the silk varies in accordance with age of the pupating larva. Thus, the closer the developing hornet to eclosion, the lower the temperature. The present study reviews and summarizes this transformation process in the silk weave from its inception until eclosion of the imago.  相似文献   
996.
Verify correspondence and compare percentage body fat (%BF) estimates by skinfold thickness (SKT), bioelectrical impedance analysis (BIA) and DEXA. Twenty voluntaries women (aged 62-79 yr) were assessed. The body fat was estimated using two different equations of SKT(Jackson (19); Durning and Womersley, (20)), BIA using two-predictions formulas (23) and DEXA. To compare mean values of %BF was used analysis of variance for repeated measures (ANOVA--Bonferroni), the correlation of the inter-method was verified by Pearson correlation coefficients (r), and correspondence between prediction formulas was tested by using the approach by Bland and Altman (25). The %BF assessed by BIA (23) shown poor correlation (r < 0.5) with two SKT equations. The %BF ranged from 31.5 +/- 5.5 to 41.2 +/- 6.1 (mean +/- SD) for Jackson (19) e DEXA, respectively. The analysis of variance shown no significant differences (p > 0.05) between methods and/or equations by BIA (RJL-CompCorp) vs. DC-Jackson (19). There were observed significant differences (p < 0.001) between all comparisons. The correspondence between RJL-CompCorp vs. Deurenberg (23) was good and the same was observed for DEXA vs. Durning and Womersley (20). Although the methods and/or equations used in this study have been commonly utilized to estimate BF in elderly subjects, they neither must be used as a standard method. Each method has limitations and the comparison can be useful for interpretation of results.  相似文献   
997.
A continuum stress measure is derived from molecular dynamics equations using a generalized mathematical homogenization (GMH) theory. GMH consists of solving a coupled fine‐scale (atomistic unit cell) problem and a coarse‐scale (continuum) problem. The fine‐scale problem derived can be interpreted as a molecular statics (at 0 K) problem, where the coarse‐scale problem derived is a constitutive law‐free continuum equation, which calculates the Cauchy stress directly from atomistics. The continuum stress derived is compared to various versions of the virial stress formula. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
998.
Eighty clients meeting criteria for panic disorder and receiving either panic control therapy (PCT; M. G. Craske, E. Meadows, & D. H. Barlow, 1994) or treatment as usual (TAU) in a managed care setting were assessed 1 and 2 years following acute treatment. PCT was provided by therapists with little or no previous exposure to cognitive-behavioral therapies. Analyses of the full intent-to-treat sample revealed no significant differences between the treatments across the follow-up period. However, when treatment completer status was added as a moderator, those receiving PCT showed lower levels of panic severity and phobic avoidance and a greater likelihood of achieving and maintaining clinically significant change. Benzodiazepine use during follow-up was associated with greater panic severity for those clients who received PCT, but no such relationship was found for TAU clients. Results are discussed in relation to the dissemination and effectiveness of PCT as well as evidence-based psychotherapies more generally. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
The gas–liquid mass transfer of a monolith operating in the Taylor flow regime is presented. Mass transfer measurements are compared with a literature model derived for single capillaries. The comparison resulted in a prediction of the unit cell length (gasbubble+liquidslug). Independent measurements of the liquid slug length showed that the predicted unit cell length is close to the measured ones. This leads to the conclusion that mass transfer models for single capillaries may indeed be used for monoliths. Additionally, it is shown that the liquid slug length may also be estimated from pressure drop measurements.  相似文献   
1000.
Preparation of monolithic catalysts   总被引:10,自引:0,他引:10  
Monolithic catalysts can be attractive replacements for conventional catalysts in randomly packed beds or slurry reactors. The conventional procedures for preparing catalysts, however, cannot simply be applied to monolithic catalysts. Different procedures are discussed on how to put a coat layer of a catalyst support material like alumina, silica, or carbon on a monolith body by either filling the pores in that support or by putting a layer on that support. Different methods to apply an active phase to the support are discussed as well. Finally, methods to convert ready-made catalysts into monolithic catalysts are presented.  相似文献   
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