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1.
This article explores the relationships between academic knowledge and the practice of research in the construction of new computer-supported research tools for e-social science. The article draws on a U.K. e-social science pilot demonstrator project, "Collaborative Analysis of Offenders' Personal and Area-based Social Exclusion," that explores the relative impact of individual and neighborhood effects on geographical crime patterns. Three main dimensions of e-social science are addressed by the project: (1) identification of new social research foci, (2) adapting research processes, and (3) developing Grid-related research tools. The integration of these dimensions shows that research-driven and user-led development of computer-mediated research using the Grid can produce relevant and innovative tools for the social sciences.  相似文献   
2.
Injuries caused by unsafe manual handling of patients are a major source of ill health in health care workers. The present study evaluated the ability of 4 classes of variable to predict use of a hoist when moving a heavily dependent patient. Variables examined were occupational role characteristics, such as hours of work and type of shift worked; biographics, including age and height; aspects of occupational context, such as number of hoists available and number of patients; and motivational variables specified by the theory of planned behavior (Ajzen, 1985) and protection motivation theory (Rogers, 1983). Regression analyses showed that background and social-cognitive variables were able to account for 59% of variance in intention to use a hoist and 41% of variance in use of the hoist assessed 6 weeks later. Height, hoist availability, coworker injunctive norm, perceived behavioral control, response cost, response benefits, and social and physical costs of not using the hoist each explained independent variance in motivation to use a hoist at work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
A characteristic EPR spectrum is observed from Photosystem I (PS I) particles that are illuminated under reducing conditions. This signal is thought to arise from the secondary electron acceptor of PS I, A1. This EPR spectrum, along with data from other spectroscopic methods, has been taken as evidence that A1 is phylloquinone. In the work reported here, we have used a methionine auxotroph of Anabaena to deuterate specifically the 2-methyl group on the phylloquinone ring. Mass spectrometry of the isolated quinone shows 65% yield in the labeling procedure. The photoaccumulated A1 EPR spectra in protonated and deuterium-labeled cells are indistinguishable, from which we conclude that the photoaccumulated radical is not phylloquinone.  相似文献   
4.
[Retraction Notice: A retraction for this article was reported in Vol 34(5) of Journal of Experimental Psychology: Human Perception and Performance (see record 2008-13337-018). All authors retract this article. Co-author Tversky and co-author Hard believe that the research results cannot be relied upon; Sandra C. Lozano takes full responsibility for the need to retract this article.] People often learn actions by watching others. The authors propose and test the hypothesis that perspective taking promotes encoding a hierarchical representation of an actor's goals and subgoals-a key process for observational learning. Observers segmented videos of an object assembly task into coarse and fine action units. They described what happened in each unit from either the actor's, their own, or another observer's perspective and later performed the assembly task themselves. Participants who described the task from the actor's perspective encoded actions more hierarchically during observation and learned the task better. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Protein‐resistant polyethylene‐block‐poly(ethylene glycol) (PE‐b‐PEG) copolymers of different molecular weights at various concentrations were compounded by melt blending with polypropylene (PP) polymers in order to enhance their antifouling properties. Phase separation of the PE‐b‐PEG copolymer and its migration to the surface of the PP blend, was confirmed by attenuated total reflectance–Fourier transform infrared, X‐ray photoelectron spectroscopy, and static water contact angle measurements. Enrichment of PEG chains at the surface of the blends increased with increasing PE‐b‐PEG copolymer concentration and molecular weight. The PP blends compounded with PE‐b‐PEG copolymer having the lowest molecular weight (875 g mol?1), at the lowest concentration (1 wt %), gave the lowest bovine serum protein adsorption (30% less) compared to that of neat PP. At higher concentrations (5 and 10 wt %), and higher molecular weights (920, 1400, and 2250 g mol?1), the PE‐b‐PEG copolymers leached‐out resulting in protein adsorption comparable to that of neat PP. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46122.  相似文献   
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Quadrupole inductively coupled plasma mass spectrometry has been used to rapidly establish the chronology of recent aquatic sediments via measurements of the activities of 239Pu, 240Pu, and the atom ratio 240Pu/239Pu. Following addition of 0.007 Bq of a 242Pu spike isotope, Pu is leached from 3-20 g aliquots of dry-ashed sediments with HNO3. A selective anion exchanger is used to preconcentrate Pu into approximately 2 mL aliquots, which are directly analyzed using a pneumatic nebulizer and double-pass spraychamber operating at 60 microL/min solution uptake rate. The ICPMS data collection is performed for 10 min per sample. The U concentrations were 0.01-0.05 microg/L in the analyzed solutions, and the interference of 238U1H+ upon 239Pu+ was negligible. The method has been applied to determining Pu activities, inventory, and 240Pu/239Pu in a complete sediment core from Old Woman Creek (Huron, OH). The Pu activity profiles, obtained in approximately 6 h of instrumental measurement time, are in agreement with a y spectrometric 137Cs profile. Peak 239+240Pu and 137Cs activities in the core were 1.60 +/- 0.02 and 47.8 +/- 0.8 Bq/kg, respectively; inventories were 108 +/- 2 Bq/m2 239+240Pu and 2710 +/- 40 Bq/m2 137Cs. Detection limits, based upon the analysis of 20 g samples, were 0.004 Bq/kg 239Pu, 0.012 Bq/kg 240Pu, and 0.012 Bq/kg 239+240Pu. 240Pu/239Pu atom ratios of 0.16-0.19 were obtained for all core intervals containing detectable Pu, which indicates that global fallout is the source of these radionuclides.  相似文献   
8.
How do people understand the everyday, yet intricate, behaviors that unfold around them? In the present research, we explored this by presenting viewers with self-paced slideshows of everyday activities and recording looking times, subjective segmentation (breakpoints) into action units, and slide-to-slide physical change. A detailed comparison of the joint time courses of these variables showed that looking time and physical change were locally maximal at breakpoints and greater for higher level action units than for lower level units. Even when slideshows were scrambled, breakpoints were regarded longer and were more physically different from ordinary moments, showing that breakpoints are distinct even out of context. Breakpoints are bridges: from one action to another, from one level to another, and from perception to conception. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
9.
[Retraction Notice: A retraction for this article was reported in Vol 137(4) of Journal of Experimental Psychology: General (see record 2008-15679-005). All authors retract this article. Co-author Tversky and co-author Hard believe that the research results cannot be relied upon; Sandra C. Lozano takes full responsibility for the need to retract this article.] People encode goal-directed behaviors, such as assembling an object, by segmenting them into discrete actions, organized as goal-subgoal hierarchies. Does hierarchical encoding contribute to observational learning? Participants in 3 experiments segmented an object assembly task into coarse and fine units of action and later performed it themselves. Hierarchical encoding, measured by segmentation patterns, correlated with more accurate and more hierarchically structured performance of the later assembly task. Furthermore, hierarchical encoding increased when participants (a) segmented coarse units first, (b) explicitly looked for hierarchical structure, and (c) described actions while segmenting them. Improving hierarchical encoding always led to improvements in learning, as well as a surprising shift toward encoding and executing actions from the actor's spatial perspective instead of the participants' own. Hierarchical encoding facilitates observational learning by organizing perceived actions into a representation that can serve as an action plan. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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