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51.
Operation of an elastomeric blade requires the use of a boundary lubricant to remove residual xerographic toner from the photoreceptor efficiently. A radioactive tracer technique was used to study the behaviour of a number of lubricants used in the xerographic process. Both filming and nonfilming type lubricants were investigated using this technique. The results indicated that the lubricant film deposited on the photoreceptor must be in the thickness range of from 1 to 3 molecular layers for acceptable xerographic development and cleaning. Film thickness was shown to be dependent on the class of lubricant, the concentration of lubricant in toner, and the inclusion of a silica compound in the toner. Films are dynamic in nature, continuously being formed and removed during the xerographic process. Parameters affecting the filming mechanism are discussed.  相似文献   
52.
Automated targeting for inter-plant water integration   总被引:1,自引:0,他引:1  
Apart from in-plant water recovery, inter-plant water integration (IPWI) offers another promising mean for the reduction of fresh water and wastewater flowrates for process plants. This paper extends the automated targeting technique that was developed for single water network into IPWI. This optimisation-based technique is based on the concept of pinch analysis, which enables the setting of various network targets prior to detailed design. The automated targeting technique is formulated as a linear programming model for which global optimum is guaranteed. The proposed technique is demonstrated using several industrial and literature examples.  相似文献   
53.
Presents an obituary for Brian Mullen. In a field that values empirical precedent and established paradigms, Brian Mullen's career was one of passion and originality. He was motivated by pure intellectual curiosity; the recognition he received for his pioneering work in archival methodology, meta-analysis, and group processes and relations was secondary. His contributions to the field of social psychology were unique and will be enduring. His 1985 book with Robert Rosenthal, BASIC Meta-Analysis: Procedures and Programs, is a classic. In 2006, he was identified as the 15th most cited scholar in social psychology textbooks. Brian died of cancer on May 4, 2006. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
Five different alkenylgold(I) phosphane complexes were prepared and then investigated in [1,1′‐bis(diphenylphosphino)ferrocene]palladium(II) dichloride‐catalyzed cross‐coupling reactions with different aryl halides, heterocyclic halides, an alkenyl halide, an alkynyl halide, allylic substrates, benzyl bromide and an acid chloride. With regard to the halides, the iodides were highly reactive, bromides or chlorides gave significantly reduced yields or failed, allylic acetates failed, too. The cross‐coupling partners contained a number of different functional groups, while free carboxylic acids did not deliver cross‐coupling products and o,o‐disubstituted arenes failed as well, a broad range of other functional groups like nitro groups, nitrile groups, ester groups, α,β‐unsaturated ester groups and lactones, aldehydes, alkoxy groups, pyridyl groups, thienyl groups, unprotected phenols and anilines, even aryl azides were tolerated. The structures of one alkenylgold(I) species and of four of the cross‐coupling products were proved by crystal structure analyses.  相似文献   
55.
Research on judgments of verbal learning has demonstrated that participants' judgments are unreliable and often overconfident. The authors studied judgments of perceptual-motor learning. Participants learned 3 keystroke patterns on the number pad of a computer, each requiring that a different sequence of keys be struck in a different total movement time. Practice trials on each pattern were either blocked or randomly interleaved with trials on the other patterns, and each participant was asked, periodically, to predict his or her performance on a 24-hr test. Consistent with earlier findings, blocked practice enhanced acquisition but harmed retention. Participants, though, predicted better performance given blocked practice. These results augment research on judgments of verbal learning and suggest that humans, at their peril, interpret current ease of access to a perceptual-motor skill as a valid index of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The conversion of n-octane on Pt/Al2O3 catalyst to hydrocracked products, isooctane, ethylbenzene, o-,p-,m-xylene and toluene was investigated in hydrogen in a Berty CSTR at three different partial pressures of n-octane, 101·325 KPa total pressure, temperatures between 400°C-460°C and W/F values up to 0·33gmincm-3. The hydrocracked products were the most predominant. Of the other products, isooctane was present in the highest yield. A sequence of elementary steps based on the suggested reaction network of Ako and Susu (1986) was found to predict the experimental conversion-W/F data with the conversion of adsorbed isooctane to adsorbed o-xylene as the rate determining step. The activation energies for the forward and backward reactions of this step were determined to be 21·2 and 14·3 Kcal/gmol, respectively.  相似文献   
58.
The 9-dot problem is widely regarded as a difficult insight problem. The authors present a detailed information-processing model to explain its difficulty, based on maximization and progress-monitoring heuristics with lookahead. In Experiments 1 and 2, the model predicted performance for the 9-dot and related problems. Experiment 3 supported an extension of the model that accounts for insightful moves. Experiments 4 and 5 provided a critical test of model predictions versus those of previous accounts. On the basis of these findings, the authors claim that insight problem solving can be modeled within a means–ends analysis framework. Maximization and progress-monitoring heuristics are the source of problem difficulty, but also create the conditions necessary for insightful moves to be sought. Furthermore, they promote the discovery and retention of promising states that meet the progress-monitoring criterion and attenuate the problem space. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
To support a more holistic approach to the contribution of packaging to efficiency and value creation in the product supply chain, a systematic evaluation method – packaging scorecard – has been developed and tested in two case studies. The packaging scorecard is based on research of functional criteria of packaging and the theories of ‘balanced scorecard’, a general management approach to evaluating organizational performance using different perspectives. The results of the case studies indicate that the method can be very useful to get a systematic overview of packaging performance throughout the product supply chain. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
60.
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