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11.
膏体充填技术作为一种将选矿尾砂排放坑内采空区并形成坚固支承体的充填技术,从20世纪80年代初期就已经在加拿大地下矿山开始使用.然而,早期的膏体充填系统设备昂贵、能耗较高,使得地下矿山最近几年来开始探求一种更经济有效的充填技术.针对这个问题,现在已经研发出一种相应的技术,它能将选矿尾砂通过沉淀、浓缩和流态化过程制出膏体.加拿大矿物能源工艺中心(CANMET)在这种新工艺的研究中所取得的成果表明,选矿尾砂能在一个尾砂仓内通过浓缩和流态过程而制成膏体用于矿山充填.  相似文献   
12.
Isolated protein motifs that are involved in interactions with their binding partners can be used to inhibit these interactions. However, peptides corresponding to protein fragments tend to have no defined secondary or tertiary structure in the absence of scaffolding by the rest of protein molecule. This results in low inhibitor potency. NMR and CD spectroscopy studies of lipopeptide inhibitors of the Hedgehog pathway revealed that membrane anchoring allows the cell membrane to function as a scaffold and facilitate the folding of short peptides. In addition, lipidation enhances cell permeability and increases the concentration of the compounds near the membrane, thus facilitating potent inhibition. The general applicability of this rational approach was further confirmed by the generation of selective antagonists of the insulin-like growth factor 1 receptor with GI(50) values in the nanomolar range. Lipopeptides corresponding to protein fragments were found to serve as potent and selective inhibitors of a number of nondruggable molecular targets.  相似文献   
13.
Presents an obituary for Ellis Paul Torrance, who passed away on July, 12, 2003, after almost 60 years of research in creativity. Known as the "Father of Creativity," Paul legitimized its study with his development of the Torrance Tests of Creative Thinking (TTCT). This battery of standardized tests, now translated into 32 languages, provided evidence that creative potential could be quantified and increased with practice. Since their development, the TTCT have been used in over 2,000 research studies, thus demonstrating Paul's influence on creativity research in the fields of psychology and education. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
Crashes at rail level crossings (RLXs) remain a persistent but ill-defined safety issue. In urban areas, RLXs are typically located in areas of high workload and visual clutter, such as busy shopping strips. Despite this, the impact of such environments on driver behaviour and compliance with RLX controls is not well understood. This study sought to examine where drivers direct their attention on approach to urban RLXs located in busy shopping strip areas, and whether this differs between novice and experienced drivers. Participants drove an instrumented vehicle around a pre-defined urban route containing several active (flashing light with boom barriers) RLXs. Drivers’ visual scanning behaviour and cognitive processes were examined on approach to RLXs. The results suggest that RLXs were not a key focus of drivers’ attention. Further, rather than actively scanning, participants were over-reliant on RLX warning signals and the behaviour of surrounding vehicles to alert them to the presence of both trains and RLXs. This study provides important insights into drivers’ visual and cognitive behaviour on approach to urban RLXs located in areas of high visual demand.  相似文献   
15.
Topological insulators exhibit a bulk energy gap and spin-polarized surface states that lead to unique electronic properties, with potential applications in spintronics and quantum information processing. However, transport measurements have typically been dominated by residual bulk charge carriers originating from crystal defects or environmental doping, and these mask the contribution of surface carriers to charge transport in these materials. Controlling bulk carriers in current topological insulator materials, such as the binary sesquichalcogenides Bi2Te3, Sb2Te3 and Bi2Se3, has been explored extensively by means of material doping and electrical gating, but limited progress has been made to achieve nanostructures with low bulk conductivity for electronic device applications. Here we demonstrate that the ternary sesquichalcogenide (Bi(x)Sb(1-x))2Te3 is a tunable topological insulator system. By tuning the ratio of bismuth to antimony, we are able to reduce the bulk carrier density by over two orders of magnitude, while maintaining the topological insulator properties. As a result, we observe a clear ambipolar gating effect in (Bi(x)Sb(1-x))2Te3 nanoplate field-effect transistor devices, similar to that observed in graphene field-effect transistor devices. The manipulation of carrier type and density in topological insulator nanostructures demonstrated here paves the way for the implementation of topological insulators in nanoelectronics and spintronics.  相似文献   
16.
Driver inattention and driver distraction represent a major problem in road safety. Although both are believed to contribute to increased crash risk, there is currently limited reliable information on their role in crashes. The current study used in-depth data from the Australian National Crash In-depth Study to investigate the role of driver distraction and inattention in serious casualty crashes. The sample included 856 crashes from 2000 to 2011, in which at least one party was admitted to hospital due to crash-related injuries. Crashes were coded using a taxonomy of driver inattention that delineates five inattention subtypes: restricted attention, misprioritised attention, neglected attention, cursory attention, and diverted attention (distraction). Approximately 45% of crashes could not be coded due to insufficient information while in an additional 15% the participant indicated the “other driver was at fault” without specifying whether inattention was involved. Of the 340 remaining cases, most showed evidence of driver inattention (57.6%) or possible inattention (5.9%). The most common subtypes of inattention were restricted attention, primarily due to intoxication and/or fatigue, and diverted attention or distraction. The most common types of distraction involved voluntary, non-driving related distractions originating within the vehicle, such as passenger interactions. The current study indicates that a majority of serious injury crashes involve driver inattention. Most forms of inattention and distraction observed are preventable. This study demonstrates the feasibility of using in-depth crash data to investigate driver inattention in casualty crashes.  相似文献   
17.
BACKGROUND: An explicit process of collaborative (shared) decision making involving the patient and physician has been recommended for discretionary surgical procedures in which small-area analysis demonstrates high variation not attributable to differences in the patient population in the area. One such example is laminectomy for lumbar herniated disk (HD). An observational study was undertaken to evaluate the impact of an HD videodisk program on patient satisfaction, decision making, and treatment preferences. METHODS: Enrollment occurred in the outpatient offices of surgeons treating Kaiser Permanente (Colorado Region) patients with HD who had indications for surgery. Enrollment took place from May 1993 to December 1995, and follow-up surveys of patients were completed by January 1997. RESULTS: A 6.0% decrease in the undecided group and a 1.3% decrease in the group preferring nonsurgical treatment drove a shift of patients toward laminectomy, from 26.7% to 35.8% (Wilcoxon signed rank test = 349.5, p = .017). Postviewing preference (74.0%) was a better aggregate predictor of the ultimate treatment than previewing preference (70.0%) for laminectomy. DISCUSSION: Viewing the videodisk increased the preference for laminectomy. However, limitations in the data prevented us from determining whether this change in preference was actually reflected in patients' ultimate decisions. The fact that the strongest predictor of choosing surgery was the patient's valuation of his or her condition supports shared decision making, with its emphasis on patient's values. Participation in other videodisk programs has been low; perhaps physicians should ask patients to view these videodisks before their visits.  相似文献   
18.
The assessment of depression in patients with brain pathologies—a topic of considerable clinical and research interest—is complicated by a variety of factors. Among the most problematic are cognitive consequences of brain injury that can diminish the reliability and validity of information used to diagnose depression, determine its severity, ascertain its predictors, and evaluate its impact. In this article, the authors examine the challenges to depression assessment in patients who have had a stroke, the neurologically impaired population in which it has been most frequently studied. Focusing on poststroke depression research, they describe methodological limitations that may contribute to conflicting outcomes and conclusions and offer suggestions for improving the specificity, consistency, validity, and reliability of assessment methods and procedures when investigating depression in patients with brain pathologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.
Approximately 40% of college students reported engaging in heavy episodic or "binge" drinking in the 2 weeks prior to being surveyed. Research indicates that college students suffering from depression are more likely to report experiencing negative consequences related to their drinking than other students are. The reasons for this relationship have not been well-studied. Hence, the purpose of this study was to determine whether use of protective behavioral strategies (PBS), defined as cognitive-behavioral strategies an individual can use when drinking alcohol that limit both consumption and alcohol-related problems, mediated the relationship between depressive symptoms and alcohol-related negative consequences among college students. Data were obtained from 686 participants from a large, public university who were referred to an alcohol intervention as a result of violating on-campus alcohol policies. Results from structural equation modeling analyses indicated that use of PBS partially mediated the relationship between depressive symptoms and alcohol-related negative consequences. Implications for clinicians treating college students who report experiencing depressive symptoms or consuming alcohol are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
20.
Kim DW  Zhang Y  Cooper KL  Wang A 《Applied optics》2005,44(26):5368-5373
We present two novel schemes for refractometry based on a long-period fiber grating- (LPG-) based Michelson interferometer. These schemes are designed to overcome the measurement dependence of previously demonstrated LPG-based refractometry on the immersion depth. The first utilizes an unshielded LPG and the second, a shielded one. Both schemes were tested over a certain refractive-index range, and the measurement of glucose concentration in water was experimentally demonstrated. In addition, the temperature sensitivity of the two schemes is discussed.  相似文献   
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