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121.
Spark Plasma Sintering (SPS) of NASICON Ceramics   总被引:1,自引:0,他引:1  
Spark plasma sintering (SPS) method was used to obtain dense NASICON ceramics with a high-electrical conductivity, which was compared with conventional solid-state sintering. The fully dense NASICON was achieved at a relatively low-sintering temperature of 1100°C, whereas the apparent density of the specimen prepared by conventional sintering was 74% of the theoretical density. The highest conductivity of 1.8 × 10−3 Scm−1 at 25°C, which is comparable to the best value reported, was achieved using the SPS process. Considering the phase, density, and microstructure, it appears that there is more room for improved conductivity by controlling the amount of monoclinic zirconia and the resistive grain-boundary glass phase.  相似文献   
122.
BACKGROUND: Groin pain is common among athletes. A major cause of long-standing problems is adductor-related groin pain. The purpose of this randomised clinical trial was to compare an active training programme (AT) with a physiotherapy treatment without active training (PT) in the treatment of adductor-related groin pain in athletes. METHODS: 68 athletes with long-standing (median 40 weeks) adductor-related groin pain--after examination according to a standardised protocol--were randomly assigned to AT or PT. The treatment period was 8-12 weeks. 4 months after the end of treatment a standardised examination was done. The examining physician was unaware of the treatment allocation. The ultimate outcome measure was full return to sports at the same level without groin pain. Analyses were by intention to treat. FINDINGS: 23 patients in the AT group and four in the PT group returned to sports without groin pain (odds ratio, multiple-logistic-regression analysis, 12.7 [95% CI 3.4-47.2]). The subjective global assessments of the effect of the treatments showed a significant (p=0.006) linear trend towards a better effect in the AT group. A per-protocol analysis did not show appreciably different results. INTERPRETATION: AT with a programme aimed at improving strength and coordination of the muscles acting on the pelvis, in particular the adductor muscles, is very effective in the treatment of athletes with long-standing adductor-related groin pain. The potential preventive value of a short programme based upon the principles of AT should be assessed in future, randomised, clinical trials.  相似文献   
123.
The domain structure and miscibility in the solid state of a series of blends of styrene‐butadiene‐styrene (SBS) block copolymers and styrene‐glycidyl methacrylate (PS‐GMA) statistical copolymers with varying molecular weights and compositions were studied using small angle X‐ray scattering and dynamic mechanical thermal analysis. Depending on the molecular characteristics of each component, different types and degrees of solubilization of PS‐GMA in SBS were found which, in addition to the initially SBS phase morphology, lead to materials with multiphase domain morphologies with differences in size and structure. The degree of solubilization of PS‐GMA into the PS domains of SBS was found to be higher for blends containing PS‐GMA with lower molecular weight (Mw = 18 100 g mol?1) and lower GMA content (1 wt%) and/or for SBS with higher PS content (39 wt%) and longer PS blocks (Mw = 19 600 g mol?1). Localized solubilization of PS‐GMA in the middle of PS domains of SBS was found to be the most probable to occur for the systems under study, causing swelling of PS domains. However, uniform solubilization was also observed for SBS/PS‐GMA blends containing SBS with composition in the range of a morphological transition (PS block Mw = 19 600 g mol?1 and 39 wt% of PS) causing a morphological transition in the SBS copolymer (cylinder to lamella). Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd  相似文献   
124.
Intelligent Service Robotics - The role of a human assistant, such as receptionist, is to provide specific information to the public. Questions asked by the public are often context dependent and...  相似文献   
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This article reports on a new instrument, the Geriatric Institutional Assessment Profile (GIAP), developed to assess (1) hospital workers' knowledge, attitudes, and perceptions regarding care of geriatric patients, and (2) the perceived adequacy of an institutional environment to serve geriatric patients' needs. Findings are reported from 303 questionnaires completed by health care employees from a 658-bed academic medical center. Internal consistency estimates were consistently high for the various components of the GIAP. Factor analysis was performed to examine underlying dimensions of knowledge and institutional environment. The GIAP has the potential to narrow the gap between actual and best practice in geriatric care by identifying staff information needs and concerns, as well as institutional barriers and facilitators to providing quality geriatric hospital care.  相似文献   
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128.
Both the Biosite Triage (Biosite Diagnostics, San Diego, CA) method and the Du Pont aca (Du Pont Company, Wilmington, DE) method give qualitative tricyclic antidepressant (TCA) results to aid in the diagnosis of a TCA overdose. The Triage method uses urine samples and the aca uses serum samples. Although the cutoff values vary considerably between the two methods, the Triage results agreed well with the aca results. The Triage test has an advantage in instrument maintenance and time savings, allowing a reduction in turn-around time for our emergency department. Both urine and serum samples were obtained from 44 patients who were admitted to the emergency department with a diagnosis of "possible tricyclic overdose." Discrepancies between the two methods were resolved by thin layer chromatography (Toxi-Lab, Ansys, Inc, Irvine, CA). Both methods were in agreement with the exception of five patients' samples. In this study, the Triage method allowed for detection of TCA using urine that is simple for the user and yielded higher sensitivity and specificity results compared with the Du Pont aca method.  相似文献   
129.
Composition and structure of lotic ecosystems can be affected by substrate instability. Consequently stream ecologists have used various methods to determine bed stability characteristics. However, the link between community composition and these measurements varies because benthic biota often responds to combinations of bed stability characteristics. This paper presents a protocol to determine reach‐scale stream bed stability in mountain streams which is relevant for invertebrate communities (Stream Bed Stability for Invertebrates, SBSI). The approach is calibrated on community composition response to bed stability but does not measure any single bed stability characteristic per se. It consists of 13 parameters that are assessed once at each reach with minimal instrumentation and low interference with the substrate. These 13 parameters cover aspects of sediment supply from banks, transport capacity and substrate erodibility as well as effects of particle transport on channel bottom structures, substrate assemblage and single grains. Application of the SBSI protocol improved the relationship between bed stability and community diversity compared to when conventional bed stability measures were employed. The SBSI protocol provides a cost‐effective and time‐effective assessment method for bed stability and its application can facilitate research on invertebrate community response to physical disturbance. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
130.
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