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181.
Francis Leonard Deepak Rodrigo Esparza Belsay Borges Xóchitl López-Lozano Miguel Jose-Yacaman 《Catalysis Letters》2011,141(4):518-524
Abstract
Aberration corrected (Cs) scanning transmission electron microscopy (STEM) has been used for the first time to characterize MoS2 catalysts (supported on Al2O3 substrates) to provide detailed information of its shape and structure. The high-resolution imaging reveals unprecedented morphologies present in the MoS2 catalyst that have never been observed before with other experimental techniques because of the insufficient image contrast and/or resolution. High angle annular dark field (HAADF)-STEM images shows very clearly that the catalyst is formed by elongated chains with a twisted and helical structure. Based on the HAADF-STEM images, we built three atomic models to illustrate the different morphologies found in the MoS2 catalyst. The existence of these nanostructures opens the posibility for novel catalyticaly active edge morphologies in MoS2-based nanocatalysts. 相似文献182.
This case study presents an innovative, technology-supported approach to teaching and learning taken within the Kelley School
of Business at Indiana University for the launch of a new Accounting MBA (AMBA) degree. The new program is proactive by treating
the pending 150 credit-hour requirement as an opportunity for major technology infusion and competitive differentiation among
graduate accounting programs. The purpose of this case study is to describe in detail the process and experience of launching
the new AMBA degree that incorporated technology-supported learning from its genesis. The case study demonstrates how vision,
partnerships with industry, a myriad of technology choices, and faculty championing enabled the successful launch of the new
degree. It provides a detailed roadmap for people at other institutions who may be planning similar technology-supported teaching
and learning initiatives.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
183.
ABET Engineering Criteria 2000 require a selection of outcomes and outcome indicators for each educational objective adopted by an engineering program. This paper describes a database created using Microsoft Access 97 © linking choices of program outcomes and choices of program outcome indicators for all of the accredited engineering programs in an academic institution. With this database, benchmarking searches can be conducted by type of engineering program, by choice of outcome, or by choice of outcome indicator. Several example searches are presented using data describing the engineering programs at Clemson University. A web-site address is given where copies of the Clemson database can be downloaded. 相似文献
184.
Schumacher Julie A.; Homish Gregory G.; Leonard Kenneth E.; Quigley Brian M.; Kearns-Bodkin Jill N. 《Canadian Metallurgical Quarterly》2008,22(6):894
Alcohol problems are one of the most well-established risk factors for physical intimate partner violence. Nonetheless, most individuals who drink heavily do so without ever aggressing against a partner. Laboratory research identifies hostility as an important moderator of the association between alcohol and general aggression, and correlational research suggests that stress and coping may also be important moderators of the alcohol-aggression link. Building on this research, the authors examined hostility, coping, and daily hassles as moderators of the associations between excessive drinking and intimate partner violence across the first 4 years of marriage in a sample of 634 newly married couples. Excessive drinking was a significant cross-sectional correlate, but it did not emerge as a unique longitudinal predictor of intimate partner violence perpetration in this sample. However, alcohol was longitudinally predictive of husband violence among hostile men with high levels of avoidance coping. Findings generally supported the moderation model, particularly for men. These findings implicate hostility, coping, and daily hassles, as well as alcohol, as potentially important targets for partner violence prevention strategies for young married couples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
185.
Mark A. Norris Leonard Meirovitch 《International journal for numerical methods in engineering》1989,28(10):2451-2463
Structures are often characterized by parameters, such as mass and stiffness, that are spatially distributed. Parameter identification of distributed structures is subject to many of the difficulties involved in the modelling problem, and the choice of the model can greatly affect the results of the parameter identification process. Analogously to control spillover in the control of distributed-parameter systems, identification spillover is shown to exist as well and its effect is to degrade the parameter estimates. Moreover, as in modelling by the Rayleigh–Ritz method, it is shown that, for a Rayleigh–Ritz type identification algorithm, an inclusion principle exists in the identification of distributed-parameter systems as well, so that the identified natural frequencies approach the actual natural frequencies monotonically from above. 相似文献
186.
Increased variety in the food supply may contribute to the development and maintenance of obesity. Thirty-nine studies examining dietary variety, energy intake, and body composition are reviewed. Animal and human studies show that food consumption increases when there is more variety in a meal or diet and that greater dietary variety is associated with increased body weight and fat. A hypothesized mechanism for these findings is sensory-specific satiety, a phenomenon demonstrating greater reductions in hedonic ratings or intake of foods consumed compared with foods not consumed. Nineteen studies documenting change in preference, intake, and hedonic ratings of food after a food has been eaten to satiation in animals and humans are reviewed, and the theory of sensory-specific satiety is examined. The review concludes with the relevance of oral habituation theory as a unifying construct for the effects of variety of sensory-specific satiety, clinical implications of dietary variety and sensory-specific satiety on energy regulation, and suggestions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
187.
Previous studies have shown that the effects of a particular class of geometric transformations, known as cardioidal strain, are perceived as growth when applied to a variety of animate and even inanimate objects. The present 3 experiments, with 30 undergraduates, demonstrated that the effects of these growth transformations are not completely independent of the object undergoing change but that they depend critically on certain structural characteristics. When cardioidal strain was applied to a straight-line, right-angle, robotlike structure, there was no consistent effect on the age level of the figure. However, as the structural contours became more curved and less angular, the effects of this transformation were seen as increasingly more like growth. In contrast, the effects of a shear transformation were not perceived as growth on any of the profiles. These findings are examined in light of the critical physical properties that may be responsible for this notion of biological forms as well as their implications for the understanding of the information about events. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
188.
JC Leonard HL Drwinga CH Kim LH Toji PK Bender RA Mulivor JC Beck 《Canadian Metallurgical Quarterly》1997,46(3):530-534
The erm family of 23S rRNA adenine-N6-methyltransferases confers resistance to all macrolide-lincosamide-streptograminB (MLS) antibiotics, but not all MLS antibiotics induce synthesis of Erm methyltransferase with equal efficiency in a given organism. The induction efficiency of a test panel of MLS antibiotics was studied by using two translational attenuator-lac reporter gene fusion constructs, one based on ermSV from Streptomyces viridochromogenes NRRL 2860 and the other based on ermC from Staphylococcus aureus RN2442. Four types of responses which were correlated with the macrolide ring size were seen, as follows: group 1, both ermSV and ermC were induced by the 14-membered-ring macrolides erythromycin, lankamycin, and matromycin, as well as by the lincosamide celesticetin; group 2, neither ermSV nor ermC was induced by the 12-membered-ring macrolide methymycin or by the lincosamide lincomycin or the streptogramin type B antibiotic ostreogrycin B; group 3, ermSV was selectively induced over ermC by the 16-membered-ring macrolides carbomycin, chalcomycin, cirramycin, kitasamycin, maridomycin, and tylosin; and group 4, ermC was selectively induced over ermSV by the 14-membered-ring macrolide megalomicin. These data suggest that the leader peptide determines the specificity of induction by different classes of MLS antibiotics and that for a given attenuator, a major factor which determines whether a given macrolide induces resistance is its size. 相似文献
189.
Serological testing for immunoglobulin G (IgG) antibodies to Helicobacter pylori has proven useful in supporting the diagnosis of infection with this organism, but the clinical value of IgA antibodies in H. pylori-related gastritis remains controversial. The purpose of our study was to determine the frequency of IgA-positive IgG-negative patients with symptoms of gastrointestinal (GI) disorders, thus assessing the clinical utility of IgA testing for H. pylori-related gastritis. It was found previously that the frequency of infected individuals in this category (IgA positive and IgG negative) is about 2%, but a large number of IgG-negative patients with GI disorders suggestive of H. pylori infection have not been investigated until now. 相似文献
190.
Horowitz Leonard M.; Rosenberg Saul E.; Ure?o Gilbert; Kalehzan B. Michelle; O'Halloran Patrick 《Canadian Metallurgical Quarterly》1989,57(5):599
We describe a new method for aggregating psychodynamic formulations of independent clinicians. 15 patients (10 female and 5 male, aged 23–41) were interviewed before they began brief dynamic psychotherapy. Different panels of 8 formulators (drawn from a pool of 72 psychodynamic clinicians with 10–38 years of clinical experience) observed each videotaped interview and wrote individual formulations. The text of each formulation was divided into thought-units, and thought-units that occurred 3 or more times were combined into a final consensual formulation. (One case was formulated twice to demonstrate the replicability of the method). Other clinical raters then read each consensual formulation and judged, for a list of interpersonal problems, whether each problem was apt to be distressing for that patient. The raters were very successful in predicting which problems were later discussed in treatment. Predictions were best for formulations with a high proportion of interpersonal content. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献