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51.
In the search of high-performance materials for lithium ion batteries, Li2CoPO4F offers many advantages like high theoretical capacity and high operating potential. The synthesis of Li2CoPO4F has been reinvestigated considering a conventional solid state reaction and an unconventional way. Due to the long heat-treatments required by the conventional approach, a beginning of grains coalescence is observed. Limiting particles growth has been allowed by a shorter reaction done by SPS (Spark Plasma Sintering). By this method, the synthesis of Li2CoPO4F was greatly shortened (from 10 h to 9 min), which favours the getting of submicrometric particles. The comparison of the electrochemical properties of the Li2CoPO4F obtained by the different ways confirms the advantages of SPS synthesis in performance enhancement.  相似文献   
52.
Biogas produced from anaerobic fermentation of organic substances represents an alternative renewable energy source. Its utilization would contribute to substantial reduction of the solid waste volume in land-filling and incineration. Biogas so produced could be utilized on site or it could be injected into the natural gas distribution network. Microbiological and chemical compositions of different biogas types were determined in order to conduct qualitative and quantitative risk assessments of the potential health hazards associated with biogas use for cooking. Biogas types that could be allowed for injection in the natural gas pipelines were listed with recommendations, while outlining the European biogas injection policy. Results indicated that the injection of the processed biogas in the distribution network did not present any additional chemical or microbiological risk to consumers when compared to natural gas, provided that the biogas resulted from the fermentation of non-dangerous waste. However, since this study did not examine the microbiological and chemical composition of biogas originating from wastewater sludges and/or industrial wastes, the injection of this type of biogas into the gas distribution network should not be allowed unless a similar risk evaluation study is conducted for each case.  相似文献   
53.
This paper presents a formal semantics for the Taverna 2 scientific workflow system. Taverna 2 is a successor to Taverna, an open-source workflow system broadly adopted within the e-science community worldwide. The new version improves upon the existing model in two main ways: (i) by adding support for data pipelining, which in turns enables input streams of indefinite length to be processed efficiently; and (ii) by providing new extensibility points that make it possible to add new operators to the workflow model. Consistent with previous work by some of the authors, we use trace semantics to describe the effect of workflow computations, and we show how they can be used to describe the new features in the Taverna 2 model.  相似文献   
54.
This article presents results from a survey of ethical beliefs about practice dilemmas unique to clinical work with children and adolescents. Survey data suggest that identical practices are not always ethically equivalent, particularly when the developmental status of the client is varied. The survey also reveals widespread ambiguity about what constitutes ethical practice, as manifested both in individual uncertainty and in the absence of group consensus. Ethically guided clinical practice is presented as a far more complex undertaking than adherence to a single set of professional standards. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
The purpose of this study was to verify the validity of a French version of the Positive and Negative Perfectionism Scale developed by L. A. Terry-Short (1995). This instrument measures the type as well as the level of perfectionism in adolescents. The instrument was first administered to 734 7th, 9th, and 11th grade students. Four weeks later, 596 Ss were invited to answer the questionnaire once more. The factorial structure, temporal stability and internal consistency of each subscales of the translated version of the instrument correspond to those of the original version. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
56.
Because errors in recall are an important contributor to assessments of children's credibility as witnesses, the author explored children's errors when recounting details of trauma injuries that resulted in hospital Emergency Room treatment. 37 preschool aged children (aged 2–5 yrs) and 11 9-yr-olds (comparison Ss) were recruited in the emergency room and interviewed at home both within a few days of the injury and after 6 mo. Adult witnesses were also interviewed to corroborate children's accounts. Although 2-yr-old Ss made more errors than did older children, the information provided was accurate, even 6 mo after their injuries. The errors were not random; rather, information that was likely to be important in real-world cases was retained quite accurately, while some other categories of information (e.g., the 1st person to respond to their injury) were more error-prone. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
This study examined drinking to cope with distress and drinking behavior in a baseline sample of 412 unipolar depressed patients assessed 4 times over a 10-year period. Baseline drinking to cope operated prospectively as a risk factor for more alcohol consumption at 1-, 4, and 10-year follow-ups and for more drinking problems at 1- and 4-year follow-ups. Findings elucidate a key mechanism in this process by showing that drinking to cope strengthened the link between depressive symptoms and drinking behavior. Individuals who had a stronger propensity to drink to cope at baseline showed a stronger connection between depressive symptoms and both alcohol consumption and drinking problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Assessed the impact of school-based social competence training on skills, social adjustment, and self-reported substance use of 282 6th and 7th graders. Training emphasized broad-based competence promotion in conjunction with domain-specific application to substance abuse prevention. The 20-session program comprised 6 units: stress management, self-esteem, problem solving, substances and health information, assertiveness, and social networks. Findings indicated positive training effects on Ss' skills in handling interpersonal problems and coping with anxiety. Teacher ratings revealed improvements in Ss' constructive conflict resolution with peers, impulse control, and popularity. Self-report ratings indicated gains in problem-solving efficacy. Results suggest some preventive impact on self-reported substance use intentions and excessive alcohol use. In general, the program was found to be beneficial for both inner-city and suburban students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
Single-walled carbon nanotubes (CNTs) convert absorbed near infrared (NIR) light into heat. The use of CNTs in the NIR-mediated photothermal ablation of tumor cells is attractive because the penetration of NIR light through normal tissues is optimal and the side effects are minimal. Targeted thermal ablation with minimal collateral damage can be achieved by using CNTs attached to tumor-specific monoclonal antibodies (MAbs). However, the role that the cellular internalization of CNTs plays in the subsequent sensitivity of the target cells to NIR-mediated photothermal ablation remains undefined. To address this issue, we used CNTs covalently coupled to an anti-Her2 or a control MAb and tested their ability to bind, internalize, and photothermally ablate Her2(+) but not Her2(-) breast cancer cell lines. Using flow cytometry, immunofluorescence, and confocal Raman microscopy, we observed the gradual time-dependent receptor-mediated endocytosis of anti-Her2-CNTs whereas a control MAb-CNT conjugate did not bind to the cells. Most importantly, the Her2(+) cells that internalized the MAb-CNTs were more sensitive to NIR-mediated photothermal damage than cells that could bind to, but not internalize the MAb-CNTs. These results suggest that both the targeting and internalization of MAb-CNTs might result in the most effective thermal ablation of tumor cells following their exposure to NIR light.  相似文献   
60.
A viable communications interface for the nonvocal handicapped that is a by-product of recent face recognition research is described. The system uses either the Karhunen-Loeve transform (KLT) or the discrete cosine transform (DCT) to encode video camera images on a subject's face. The encoding differentiates among three expressions: tongue out which is classified as `yes'; mouth open, which is classified as `no'; and mouth closed, which is classified as `null'. A review of the theory of the KLT and DCT is included  相似文献   
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