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排序方式: 共有282条查询结果,搜索用时 593 毫秒
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Schoop Laura H.; Herrman Todd D.; Johnstone Brick; Callahan Charles D.; Roudebush Inga S. 《Canadian Metallurgical Quarterly》2001,46(3):279
Objective: To examine the clinical value of two 7-subtest versions of the Wechsler Adult Intelligence Scale-III (WAIS-111): one using Block Design (WAIS-III/BD7) and another using Matrix Reasoning (WAIS-III/MR7) among persons with traumatic brain injury (TBI). Study Design: Actual obtained scores from the full WAIS-111 were compared with scores that would have been obtained using each of the two abbreviated versions. Participants: One hundred eighteen persons with TBI tested consecutively in an academic medical center outpatient neuropsychology laboratory. Results: For the WAIS-IIVBD7, corrected validity coefficients were .97 (Verbal IQ [VIQI), .94 (Performance IQ [PIQ]), and .97 (Full Scale IQ [FSIQJ); 92%, 70%, and 92% of scores fell within 5 points of full version scores for VIQ, PIQ, and FSIQ, respectively. WAIS-III/MR7 corrected validity coefficients were .97 (VIQ), .95 (PIQ), and .97 (FSIQ); 92%, 76%, and 92% of short-form scores were within 5 points of actual scores for VIQ, PIQ, and FSIQ, respectively. Conclusions: Both abbreviated versions demonstrated acceptable psychometric characteristics, but the matrix reasoning version may be more advantageous in assessing persons with TBI because it can be used with persons who have TBI-related motor skills impairment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A software-guided, continuous reaction calorimeter based on thermoelectric modules for direct heat flux measurements is presented. Sensors and actuators of the calorimeter's setup are implemented within a lab automation system, which enables the automated calibration of the heat flux sensors and investigations of chemical reactions through sequential function charts. Functionality of the calibration is shown by heat transfer experiments. Additionally, the calorimeter's performance is demonstrated by good agreement of conducted neutralization experiments with literature data. 相似文献
96.
D. Tsogtkhankhai S. V. Mamyachenkov O. S. Anisimova S. S. Naboichenko 《Russian Journal of Non-Ferrous Metals》2011,52(2):135-139
Conditions for the effective dissolution of sulfides without the isolation of elemental sulfur and iron oxides are determined
at 20 and 100°C using “potential-pH” thermodynamic diagrams in the Cu-Fe-S-N-O-H system. The acquired thermodynamic characteristics
of leaching of the copper concentrate with nitric acid can be used when selecting the production parameters for processing
the copper concentrates. 相似文献
97.
Trends of distributed generation development in Lithuania 总被引:1,自引:0,他引:1
The closure of Ignalina Nuclear Power Plant, impact of recent global recession of the economy, as well as changes and problems posed by the global climate change require significant alterations in the Lithuanian energy sector development. This paper describes the current status and specific features of the Lithuanian power system, and in particular discusses the role of the distributed generators. Country's energy policy during last two decades was focused on substantial modernisation of the energy systems, their reorganisation and creation of appropriate institutional structure and necessary legal basis. The most important factors stimulating development of distributed generation in Lithuania are the following: international obligations to increase contribution of power plants using renewable energy sources into electricity production balance; development of small (with capacity less than 50 MW) cogeneration power plants; implementation of energy policy directed to promotion of renewable energy sources and cogeneration. Analysis of the legal and economic environment, as well as principles of regulation of distributed generation and barriers to its development is presented. 相似文献
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Inga Wobker Peter Kenning Marco Lehmann-Waffenschmidt Gerd Gigerenzer 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2014,9(3):231-242
This research investigates Minimal Economic Knowledge (MEK) of consumers in Germany—that is, basic economic knowledge needed for understanding and successfully participating in the economy. First we develop a scale for measuring MEK in four economic domains: finance, labour economics, consumption, and public economics, testing for three kinds of knowledge within each domain, namely facts, concepts, and causal relationships. Second, we conduct an empirical study to test MEK level and influence of demographic drivers in a representative sample of German adult consumers (N = 1,314), with a mean result of only 59.4 points (of 100), indicating a considerable lack of even minimal economic knowledge. And third, using a subsample, we study factors that result in differences in the level of MEK showing among others that the choice of “sensationalist” versus “serious” news sources, both on television and in newspapers, is associated with a loss of about 10 MEK points, while, surprisingly, participating in an economics course did not enhance minimal economic knowledge. The article closes with a discussion of implications for consumer policy-making. 相似文献
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Effect of sorbate planarity on environmental black carbon sorption 总被引:11,自引:0,他引:11
Cornelissen G Elmquist M Groth I Gustafsson O 《Environmental science & technology》2004,38(13):3574-3580
Soot and charcoal, collectively termed "black carbon" or BC, can exhibit extremely strong sorption of many hydrophobic organic compounds. In order to include BC sorption in fate models, it is important to know BC nanopore surface areas. In addition, it is useful to know for which compounds BC sorption can be expected to be important. By nitrogen adsorption measurements at ultralow pressures on sediment that was strongly enriched in BC by HF treatment and/or chemothermal oxidation at 375 degrees C, we found that environmental BC has nanoporosity in the <4-10 A size range. The nanopore surface area (<50 A) of BC in Lake Ketelmeer (The Netherlands) sediment was approximately 58 m2/g. We measured sorption isotherms over a wide concentration interval for four compounds with the same Kow (10(46+/-0.1): planar anthracene (ANT), phenanthrene (PHE), and 4-chlorobiphenyl (4-PCB) along with nonplanar 2,2'-dichlorobiphenyl (2,2'-PCB). The environmental BC sorption coefficients of these iso-Kow compounds decreased in the order ANT > PHE approximately 4-PCB > 2,2'-PCB and spanned a factor of 50-200, depending on concentration. Nonplanar 2,2'-PCB showed much more linear BC sorption (nF = 0.92) than the planar compounds (nF = 0.54-0.70). This shows that steric hindrance strongly attenuates BC-sorbate interactions for a nonplanar PCB. Thus, BC is more important for environmental sorption of planar compounds (>50% sorbed to BC in the nanogram per liter range) than for nonplanar ones (<10-20%). Using the measured BC nanopore surface area, a close agreement between modeled and measured BC sorption data could be found. 相似文献