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991.
Photocatalytic routes to dechlorinate polychlorinated biphenyls (PCBs) have considerable potential for development. This paper describes efficient dye-photocatalyzed processes which can be driven by long wavelength light sources including light-emitting diodes (LEDs), fluorescent lamps, and quite probably sunlight. The reduced form of methylene blue (MB), leuco-methylene blue (LMB), has previously been found to photoinduce dechlorination of chloroaromatics with an electron transfer from its triplet excited state. Sodium borohydride, used in this case is an efficient sacrificial reductant, which can maintain LMB as the major species in competition with air oxidation of LMB to MB. There is also evidence that it plays a further (chain reaction) role in promoting the LMB photodechlorination process as well. The generality of the photoelectron transfer from reduced members of the phenothiazine dye family is demonstrated with phenothiazine and leuco-methylene green when a wavelength (UV) is chosen to produce the highly reductive triplet. It is likely that dechlorination can be initiated by many triplet excited states with adequate reduction potential. 相似文献
992.
Using a series of four case studies, this article illustrates the integration of statistical process control and designed experiments. For such an integration to be effective, this article points out the need to use statistical process control (SPC) as a tool for active process study, rather than simply as a method for maintaining and controlling processes. The use of SPC in this fashion is also illustrated throughout the case studies. 相似文献
993.
Cooper Alvin; Scherer Coralie R.; Boies Sylvain C.; Gordon Barry L. 《Canadian Metallurgical Quarterly》1999,30(2):154
A growing number of clients are presenting in therapy with problems related to their on-line sexual habits. Adults who had used the Internet for sexual pursuits at least once (N?=?9,177) completed a 59-item on-line survey. Men and women generally behaved differently, and most (92%) indicated their on-line sexual behaviors were not problematic. Heavy users (8%) reported significant problems typically associated with compulsive disorders. Problems were highly correlated with time spent on-line for sex. Results are discussed in terms of their research and practice implications, including diagnosis and treatment. Recommendations are made for outreach prevention programs and future policies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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BACKGROUND: Aging changes in different body system are well described, but few studies have considered the relationship between them. OBJECTIVE: The purpose of this study was, therefore, to investigate the interrelationships between markers of aging in different parts of the body. METHODS: A cross-sectional study design was used. Structural and functional markers of aging were measured in a number of different body systems. RESULTS: Conditional independence analysis demonstrated that the aging markers selected clustered into two groups, either related to chronological age or adult height. Visual acuity, lens opacity, hearing threshold, cognitive decline, and the number of teeth were associated with age, while systolic blood pressure and skin thickness were related to height. Grip strength was associated with both. CONCLUSIONS: The differential associations of the aging markers with chronological age and adult height suggest that different systems do not age together. This may have relevance for understanding what underlies aging, and these preliminary findings now require replication in other aging cohorts. 相似文献
996.
Inhibition conflict theory predicts that alcohol will decrease condom use only among individuals who are highly conflicted about using a condom, whereas expectancy theory predicts such an effect only among individuals who hold strong beliefs about alcohol's effects on sexual risk taking. In Study 1, the first of these two theories was tested using a newly developed measure of conflict. Data from 308 college students who reported on the first time they had sexual intercourse with their most recent partner (FMRP) supported the utility of this measure and showed that quantity of alcohol consumed was negatively associated with condom use only among high-conflict individuals. In Study 2, 17–25-year-old respondents reported on their first sexual intercourse, FMRP, and last intercourse (ns = 465, 1136, and 984, respectively). In a simultaneous test of both inhibition conflict theory and expectancy theory, amount of alcohol consumed was found to be negatively associated with condom use at first intercourse among individuals high in both conflict and expectancy, at FMRP among high-expectancy individuals, and at last intercourse among high-conflict individuals. These results lend partial support to both theories of alcohol's effects and suggest that an integration of these two perspectives will ultimately be required if researchers are to model adequately alcohol's effects on human social behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Psychologists serving as consultants to campus prevention efforts focused on changing students' misuse of alcohol and drugs can greatly enhance the effectiveness of such programs. This article outlines the context of substance abuse problems within college and university settings as well as the traditional models of prevention and current challenges to their effectiveness. It then goes on to describe the fundamental principles of an initiator-catalyst consultation approach, along with a specific illustration of a prevention program based on this model and data highlighting the results. While this article focuses on the issue of alcohol and drug abuse problems with college students as the consultee target group and the campus as the environment, it is suggested that the initiator-catalyst approach would easily generalize to other settings with different populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Rory A Cooper 《IEEE engineering in medicine and biology magazine》2008,27(2):10-11