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771.
Although patient handlers suffer from low-back injuries at an alarming rate worldwide, there has been limited research quantifying the risk for the specific tasks performed by the patient handlers. The current study used both a comprehensive evaluation system (low-back disorder risk model) and theoretical model (biomechanical spinal loading model) to evaluate risk of LBD of 17 participants (12 experienced and five inexperienced) performing several patient handling tasks. Eight of the participants were female and nine were male. Several patient transfers were evaluated as well as repositioning of the patient in bed; these were performed with one and two people. The patient transfers were between bed and wheelchair (fixed and removable arms) and between commode chair and hospital chair. A 'standard' patient (a 50 kg co-operative female; non-weight bearing but had use of upper body) was used in all patient handling tasks. Overall, patient handling was found to be an extremely hazardous job that had substantial risk of causing a low-back injury whether with one or two patient handlers. The greatest risk was associated with the one-person transferring techniques with the actual task being performed having a limited effect. The repositioning techniques were found to have significant risk of LBD associated with them with the single hook method having the highest LBD risk and spinal loads that exceeded the tolerance limits (worst patient handling job). The two-person draw sheet repositioning technique had the lowest LBD risk and spinal loads but still had relatively high spinal loads and LBD risk. Thus, even the safest of tasks (of the tasks evaluated in this study) had significant risk. Additionally, the current study represented a 'best' case scenario since the patient was relatively light and co-operative. Thus, patient handling in real situations such as in a nursing home, would be expected to be worse. Therefore, to have an impact on LBD, it is necessary to provide mechanical lift assist devices.  相似文献   
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773.
Decoupling of InAs quantum dot (QD) size and density on AlxGa1?xAs surfaces (x = 0, 0.15, 0.30, and 0.45) is achieved by using a low growth rate and careful control of the temperature. The deposition rate of 0.01 μm/h, instead of 0.05 μm/h, allows the QDs to ripen with additional InAs deposition while the substrate temperature (490–520 °C) determines the QD density. On the GaAs surface, an increase of 10 °C results in an order of magnitude lower QD density. The increase of Al in the AlxGa1?xAs surfaces results in a higher dot density, lower dot size, and an increased size distribution. All surfaces show reduced QD density with increasing temperature and an identical zero dot density temperature at 523 °C. The GaAs surface shows increasing QD height with temperature while the AlxGa1?xAs surfaces show the opposite trend, but the InAs volume fraction in QDs for all surfaces decreases with increasing temperature, implying a more stable wetting layer. Increasing Al content also increases the InAs volume fraction in QDs, implying the wetting layer for all but the 520 °C samples is less than one monolayer. Photoluminescence samples demonstrate ground state QD energies above the GaAs bandedge.  相似文献   
774.
High-resolution magnetic resonance imaging (MRI) has been used, for the first time, to measure fluorine concentration profiles with a high spatial resolution (5 μm) along the full film depth of fluorinated polyurethane films. The MRI fluorine profiles were consistent with the results obtained by X-ray photoelectron spectroscopy (XPS) in combination with microtoming. MRI is a nondestructive and potentially quantitative technique for probing the spatial distribution of small quantities of fluorine in coatings and multi-layered systems.  相似文献   
775.
This study evaluated the short-term effectiveness of cognitive- behavioral treatment (CBT) for substance abuse delivered in a community setting. At entry into outpatient community substance abuse treatment, participants (N=252) were randomly assigned to 3 conditions: high-standardization CBT, low-standardization CBT, and treatment as usual. Treatment consisted of 12 weekly individual therapy sessions. There was a significant decrease in substance use from baseline, with participants reporting being abstinent on 90% of within-treatment days and 85% of days during the 6 months posttreatment. However, there were no significant differences in outcomes across conditions. Findings do not support the hypothesis that disseminating CBT to community settings will improve outcomes and suggest that standard substance abuse counseling may be more effective than previously thought. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
776.
777.
Patient subtypes (Types A and B alcoholism), determinants, and outcomes associated with changes in coping responses of 133 alcoholic patients in the year following admission to treatment were examined. In general, patients' use of avoidance coping declined and use of approach coping increased. Type B patients used more avoidance coping than did Type A patients, but the subtypes did not differ in rate of change in coping. As a determinant of coping, cognitive appraisal of threat showed a trend toward predicting avoidance coping at 6- and 12-month follow-ups. Decreased cognitive avoidance coping (e.g., daydreaming) predicted fewer alcohol, psychological, and interpersonal problems. Increased behavioral approach coping (e.g., taking action) predicted lower severity of alcohol problems. Further study of changes in the cognitive aspects of coping (i.e., appraisals and cognitive avoidance coping) is needed to determine mechanisms underlying cognitive processes associated with treatment outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
778.
Cellulose-based packaging materials are currently the most commonly used food packaging materials due to their light weight, stability and affordable price. However, the use of recycled paper and board adds to the risk that undesirable substances migrate into the packed goods, since contaminants are not completely removed during the recycling process and can accumulate in the final product. The only available fast and practical solution that can be used to reduce the migration of these substances is the application of functional barriers in the packaging. The applied barriers are currently mostly synthetic, which either serve only a moderate barrier function and/or have the disadvantage that it is often more complex and expensive to recycle the resulting packaging material. The aim of this project is to evaluate different bio-based or biodegradable polymers with regards to their barrier properties. Due to the fact that the transport phenomena are mainly driven by (gas phase) migration, methods based on gas chromatography (GC), including GC coupled with mass spectrometry (GC-MS) and flame ionization detection (GC-FID), GC-FID coupled online with high pressure liquid chromatography (HPLC-GC-FID), and comprehensive GCxGC-MS were used to qualify and quantify the migrated substances. This use of a wide range of different methods and instruments yielded excellent results, allowing us to comprehensively characterize the biopolymers and their barrier function.  相似文献   
779.
Due to the importance of powder flow properties and the variety of available measuring methods, several studies were published regarding the comparison of different flow properties testers. Within this work, a ring shear tester from Dr. Dietmar Schulze and a powder flow tester from Brookfield Engineering Laboratories Inc. were compared for cumin (Cuminum cyminum L.), oregano (Origanum vulgare), and onion (Allium cepa) powder and granules. The spices showed similar flow behavior from both methods. Flow function plots and effective angle of internal friction measurements indicated contiguous trends and showed that the methods were comparable.  相似文献   
780.
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