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111.
This study examined the associations among mothers' insightfulness into their infants' internal experience, mothers' sensitivity to their infants' signals, and infants' security of attachment to their mothers. The insightfulness of 129 mothers of 12-month-old infants was assessed by showing mothers 3 videotaped segments of observations of their infants and themselves and interviewing them regarding their infants' and their own thoughts and feelings. Interviews were classified into 1 insightful and 3 noninsightful categories. Mothers' sensitivity was assessed during play sessions at home and at the laboratory, and infant-mother attachment was assessed with the Strange Situation. Mothers classified as positively insightful were rated as more sensitive and were more likely to have securely attached children than were mothers not classified as positively insightful. Insightfulness also accounted for variance in attachment beyond the variance explained by maternal sensitivity. These findings add an important dimension to research on caregiving, suggesting that mothers' seeking of explanations for the motives underlying their infants' behavior is related to both maternal sensitivity and infant attachment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
112.
Traditional sunflower oil (SO), randomized lipid (RL) and specific structured lipid (SL), both produced from SO and tricaprylin/caprylic acid, respectively, were stored for up to 12 wk to compare their oxidative stabilities by chemical and sensory analyses. Furthermore, the effect of adding a commercial antioxidant blend Grindox 117 (propyl gallate/ citric acid/ascorbyl palmitate) or gallic acid to the SL was investigated. The lipid type affected the oxidative stability: SL was less stable than SO and RL. The reduced stability was most likely caused by both the structure of the lipid and differences in production/ purification, which caused lower tocopherol content and higher initial levels of primary and secondary oxidation products in SL compared with RL and SO. Grindox 117 and gallic acid did not exert a distinct antioxidative effect in the SL oil samples during storage.  相似文献   
113.
Calculations of the energetics of multiply twinned particles (MTPs) such as icosahedra and decahedra with fivefold symmetry as well as face-centered cubic (fcc) and hexagonal close-packed (hcp) particles in the size interval from 13 up to ∼ 45,000 atoms were made applying Lennard-Jones potentials. We essentially extended the size interval comparatively with previous studies and included shape-optimized hcp clusters in the global energy analysis that gives rise to the new insight into the basic fcc/hcp problem. For the cluster size N from minimal up to N ∼ 2000 atoms the binding energy is highest for icosahedra, in the size interval from 2000 up to ∼ 11,500 atoms decahedra prevail, above N ∼ 11,500 atoms decahedra and optimized fcc clusters were found to alternate. The hcp structure was revealed to become favorable above N ∼ 34,000 atoms. Thus, hcp clusters can attain their preference with respect to MTPs (comprising fcc fragments) and optimized fcc clusters only for very large sizes. The comparison with several other models is suggested and the opportunity of experimental observations is discussed.  相似文献   
114.
微型固体火箭发动机内弹道的数值模拟   总被引:1,自引:0,他引:1  
随着计算流体力学(CFD)的不断发展, 利用计算机对火箭发动机燃烧室内的气体流动过程进行数值模拟已经成为固体火箭发动机设计中非常重要的一种研究手段, 越来越受到研究人员的重视.文中使用通用流体软件对微型火箭发动机进行内弹道特性的数值模拟进行了研究, 并通过与理论计算所得数值的比较,证明了模拟结果的正确性.  相似文献   
115.
Examined the development of children's motivations to socially compare in a situation in which they were free to seek or not seek information about how another child was doing. 16 males and 16 females each at the kindergarten, 1st, and 2nd grade levels were recruited through the newspaper and paid to participate. Pairs of Ss in the same grade worked on a speed task under high- and low-competition conditions. The frequency and duration with which Ss pushed a button to observe their partner's progress on a monitor was the index of the strength of motivation. Results show the expected developmental increase in comparison behavior. Only in 2nd graders did the expected positive relationship between level of competition and performance appear. At the kindergarten level, the means were in the opposite direction, while for the 1st-grade level the relation between competition and performance depended on sex. Results are discussed in terms of alternative predictions derived from theories by L. Festinger (1954) and J. Veroff (1969). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
116.
Measured the effectiveness of A. P. Goldstein's (1973) Structured Learning Training (SLT) for teaching confrontation skills to 56 trainees varying in conceptual development (Paragraph Completion Test). Both a self-instruction approach and a standard implementation of SLT were effective for teaching confrontation skills. When trainees' conceptual level (CL) was considered, the approaches proved differentially effective (as measured by pencil-and-paper tests). Self-instruction SLT was more effective with high CL trainees than with low CL trainees; guided-instruction SLT proved more effective than self-instruction SLT with low CL trainees in each treatment. Further, differences due to instructional approach and CL failed to reach significance when the dependent variable was assessed via taped role play. Findings suggest the need for multiple ways of assessing skills as well as multiple approaches for instruction. Further investigation seems necessary to specify the variables involved in maximizing the effect of instruction. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
117.
Video-enhanced microscopy combined with the use of a computer frame memory extends considerably the useful range of our video enhanced contrast (AVEC) methods for polarizing, double-beam interference and differential interference contrast microscopy. Increased visual contrast is achieved by two stages of amplifications: the first optical, by using high bias retardation settings, and the second electronic. These steps are followed by a reduction of background brightness by means of a clamp voltage applied to a DC restoration circuit of the video camera. One of the limitations of the AVEC method alone is the inevitable appearance under high gain conditions of a pattern of mottle due to inaccessible dirt and defects in the lenses even of high quality. This limitation has been circumvented by storing the mottle pattern in the frame memory (frame store) and continuously subtracting it from each succeeding frame to clear the image. A major gain in image quality has resulted. In polarizing microscopy, the frame memory can be used also to subtract the image at one compensator setting from that at the equivalent setting of opposite sign, thus removing from the final image not only most of the mottle pattern but also the contrast due to the bright-field contrast. In the polarizing microscope, these manipulations of the raw video image make it possible to observe and measure the birefringence of various organelles and elements such as microtubules, intermediate filaments and bundles of as few as a half dozen actin filaments. Since scattered light is also removed from the image, features hidden from view in the unprocessed image become visible. In differential interference microscopy, the AVEC method makes visible (i.e. detectable) many linear elements and particles that are an order of magnitude smaller than the resolution limit and not visible in the optical image. Such features are inflated by diffraction, however, to Airy disk size.  相似文献   
118.
Examined the development of an awareness (metamemory) of "constructive interference." This is the "fact" that when children and adults are presented a list of semantically related sentences, they later find it more difficult to distinguish old from new instances than when they are presented a list of unrelated sentences. Knowledge of this constructive interference was tested by having 192 11-, 15- and 22-yr-old students first predict recognition and then take an actual recognition test. In independent groups, half of the Ss received lists of semantically related sentences, and half received lists of semantically unrelated sentences. By comparing Ss' predictions with their actual performances across the different groups, it appears that the 11-yr-olds did not comprehend this phenomenon, but the 15- and 22-yr-olds did. That is, older Ss correctly predicted that recognition performance would be poorer for related lists than for unrelated lists. The 11-yr-olds, by contrast, predicted that recognition would be about the same for the 2 kinds of lists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
119.
The mesial temporal and lateral frontal lobes were the most common sites of parenchymal abnormality on magnetic resonance imaging (MRI) scans for 12 patients with chronic traumatic brain injury (TBI). Ventricular widening was also common, and 3 patients showed increased size of the upper third ventricle. Of 10 right-handed TBI patients with no evidence of learning disability, 6 showed dominant temporal lesions and 3 showed an increase in the size of the upper third ventricle. Only patients with dominant temporal lesions (4 of 6) exceeded the normal confidence interval (based on 20 non-TBI controls) for intrusion errors on delay trials of the California Verbal Learning Test (CVLT), though other patients also demonstrated impaired recall. The pattern of increased intrusions during CVLT delay trials was confirmed in non-TBI patients who had undergone dominant temporal surgery or had dominant or bilateral temporal lesions, even when frontal changes could be ruled out. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
120.
The present study was undertaken to investigate the potential suitability of the Mongolian gerbil as a useful animal model to study the effects of dietary fats on plasma cholesterol levels. Semipurified diets containing either 20% lard, 20% safflower oil, or 19.5% beef tallow +0.5% safflower oil were equalized to contain 0.01% cholesterol and 0.05% plant sterol and were fed for a four week experimental period. The proportions of total calories contributed by fat, protein and carbohydrate (starch/sucrose ratio of 2∶1) were 40, 14 and 46%, respectively, so as to approach the distribution of calories within the average North American diet. Free, esterified, and total plasma cholesterol levels of male gerbils were determined weekly by gas liquid chromatography after drawing blood via a serial sampling technique. After 1, 2, 3, and 4 weeks of feeding the experimental diets, total cholesterol levels were lowest in the safflower oil fed animals; the corresponding values were 19–64% greater in gerbils fed lard and 68–91% greater in those consuming the beef tallow diet. Cholesterol in the free form generally responded more dramatically to the type of dietary lipid than did cholesterol in the ester form. Irrespective of the type of dietary lipid or the length of the feeding trial, 18–23% of the total plasma cholesterol was in the free form and 77–82% was present as the ester. In view of the similarity to the human of the relative proportions of free versus esterified cholesterol, the type of cholesteryl esters, and their response to dietary manipulation, the gerbil appears to be a useful animal model for studying the regulatory effect of dietary lipid on plasma cholesterol levels. Presented in part at the A.O.C.S. Annual Meeting, San Francisco, CA, May 1979.  相似文献   
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