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The health and wellbeing of future generations will depend on humankind's ability to deliver sufficient nutritious food to a world population in excess of 9 billion. Feeding this many people by 2050 will require science‐based solutions that address sustainable agricultural productivity and enable healthful dietary patterns in a more globally equitable way. This topic was the focus of a multi‐disciplinary international conference hosted by Nestlé in June 2015, and provides the inspiration for the present article. The conference brought together a diverse range of expertise and organisations from the developing and industrialised world, all with a common interest in safeguarding the future of food. This article provides a snapshot of three of the recurring topics that were discussed during this conference: soil health, plant science and the future of farming practice. Crop plants and their cultivation are the fundamental building blocks for a food secure world. Whether these are grown for food or feed for livestock, they are the foundation of food and nutrient security. Many of the challenges for the future of food will be faced where the crops are grown: on the farm. Farmers need to plant the right crops and create the right conditions to maximise productivity (yield) and quality (e.g. nutritional content), whilst maintaining the environment, and earning a living. New advances in science and technology can provide the tools and know‐how that will, together with a more entrepreneurial approach, help farmers to meet the inexorable demand for the sustainable production of nutritious foods for future generations. © 2015 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
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An investigation is reported here which aims to study the possibility of recycling waste polyurethane powder by melt blending with polypropylene. Improvement in the technological properties is found to be possible by increasing the miscibility of the blend by using a series of maleic-anhydride based compatibilizers. Mechanical properties were found to increase with increase in the compatibilizer content. It is claimed that the explanations given in this paper are unique in that through the use of a series of maleic anhydride based compatibilizers with PU/PP blends, it is possible to get materials with high mechanical properties which is corroborated by morphological and contact angle studies.  相似文献   
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Corticosteroid hormone action is controlled at a pre-receptor level by the activity of two isoforms of 11beta-hydroxysteroid dehydrogenase (11beta-HSD), catalyzing the interconversion of hormonally active cortisol to inactive cortisone. In particular 11beta-HSD2 protects the mineralocorticoid receptor (MR) from glucocorticoid excess, enabling aldosterone to interact with the MR. We have analyzed the subcellular localization of 11beta-HSD2 in relation to the expression of the MR in human colon and placenta. 3H-aldosterone binding studies confirmed expression of the MR in human colon but not term placental trophoblast. Enzyme activity studies and Western blot analyses carried out on subcellular fractions confirmed the presence of 11beta-HSD2 in microsomes. In colon, but not placenta, 11beta-HSD2 was also localized to the microsome-free, nuclear fraction. Protection upon the MR by 11beta-HSD2 in "classical" mineralocorticoid target tissues such as colon can be subserved at both a nuclear and extra-nuclear level. Tissue specific factors are responsible for the subcellular localization of 11beta-HSD2 and we postulate that one such factor may be the MR itself.  相似文献   
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A 1981 Massachusetts Department of Public Health study confirmed a childhood leukemia cluster in Woburn, Massachusetts. Our follow-up investigation attempts to identify factors potentially responsible for the cluster. Woburn has a 130-year industrial history that resulted in significant local deposition of tannery and chemical manufacturing waste. In 1979, two of the city's eight municipal drinking water wells were closed when tests identified contamination with solvents including trichloroethylene. By 1986, 21 childhood leukemia cases had been observed (5.52 expected during the seventeen year period) and the case-control investigation discussed herein was begun. Nineteen cases and 37 matched controls comprised the study population. A water distribution model provided contaminated public water exposure estimates for subject residences. Results identified a non-significant association between potential for exposure to contaminated water during maternal pregnancy and leukemia diagnosis, (odds ratio = 8.33, 95% CI 0.73-94.67). However, a significant dose-response relationship (P < 0.05) was identified for this exposure period. In contrast, the child's potential for exposure from birth to diagnosis showed no association with leukemia risk. Wide confidence intervals suggest cautious interpretation of association magnitudes. Since 1986, expected incidence has been observed in Woburn including 8 consecutive years with no new childhood leukemia diagnoses.  相似文献   
107.
Setting a framework for resolving a dispute in arbitration is essential to make the process work. Kevin R. Casey and Marissa Parker, of Philadelphia, take a hard look at arbitration practice, and provide tips for your ADR game plan and for advising your client on getting to a successful resolution.  相似文献   
108.
The objectives of this research were to investigate the accuracy and precision with which trained and untrained participants estimate the magnitude of forceful exertion and to evaluate the mathematical relationship between actual and estimated exertion. Three groups of participants estimated, as a percentage of maximum voluntary contraction (%MVC), the magnitude of submaximal exertion for 12 simulated tasks. In addition to the control group, one group was exposed to one physical benchmark (100% MVC) and another to three benchmarks (25%, 75%, and 100% MVC) prior to force estimation. Error (estimated minus actual) significantly decreased (p < .0001) from 14% MVC to 4% MVC with one benchmark and to -3% MVC with three benchmarks, as compared with the control group. Furthermore, the standard deviation decreased significantly (p < .0001 ) from the control group (16.6% MVC) to the one-benchmark group (13.8% MVC) to the three-benchmark group (11.6% MVC), indicating improved precision. Significant interaction effects were observed, but their impact on main effects was negligible. Also, linear, power, and logarithmic regression models described the relationship between perceived and actual exertion equally well (R2 = .64-.81). Applications of this research include improving the accuracy and precision of field-based psychophysical estimates of forceful exertion for epidemiological research and other field-based analyses.  相似文献   
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When recalling key term definitions from class materials, students may recall entirely incorrect definitions, yet will often claim that these commission errors are entirely correct; that is, they are overconfident in the quality of their recall responses. We investigated whether this overconfidence could be reduced by providing various standards to middle school students as they evaluated their recall responses. Students studied key term definitions, attempted to recall each one, and then were asked to score the quality of their recall. In Experiment 1, they evaluated their recall responses by rating each response as fully correct, partially correct, or incorrect. Most important, as they evaluated a particular response, it was presented either alone (i.e., without a standard) or with the correct definition present. Providing this full-definition standard reduced overconfidence in commission errors: Students assigned full or partial credit to 73% of their commission errors when they received no standard, whereas they assigned credit to only 44% of these errors when receiving the full-definition standard. In Experiment 2, a new standard was introduced: Idea units from each definition were presented, and students indicated whether each idea unit was in their response. After making these idea-unit judgments, the students then evaluated the quality of their entire response. Idea-unit standards further reduced overconfidence. Thus, although middle school students are overconfident in evaluating the quality of their recall responses, using standards substantially reduces this overconfidence and promises to improve the efficacy of their self-regulated learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Laser surgery, or laser-induced thermal therapy, is a minimally invasive alternative or adjuvant to surgical resection in treating tumors embedded in vital organs with poorly defined boundaries. Its use, however, is limited due to the lack of precise control of heating and slow rate of thermal diffusion in the tissue. Nanoparticles, such as nanoshells, can act as intense heat absorbers when they are injected into tumors. These nanoshells can enhance thermal energy deposition into target regions to improve the ability for destroying larger cancerous tissue volumes with lower thermal doses. The goal of this paper is to present an integrated computer model using a so-called nested-block optimization algorithm to simulate laser surgery and provide transient temperature field predictions. In particular, this algorithm aims to capture changes in optical and thermal properties due to nanoshell inclusion and tissue property variation during laser surgery. Numerical results show that this model is able to characterize variation of tissue properties for laser surgical procedures and predict transient temperature fields comparable to those measured by in vivo magnetic resonance temperature imaging techniques. Note that the computational approach presented in the study is quite general and can be applied to other types of nanoparticle inclusions.  相似文献   
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