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991.
A mathematical model of wood pyrolysis is presented that is in satisfactory agreement with experimental reaction product distributions over a range of conditions of practical importance for gasification and combustion. Both chemical and physical processes are described, using fundamental principles. Inclusion of water release, tar cracking and char deposition chemical reactions results in predictions of ultimate product distributions (gas, tar and char yields) that are in good agreement with experiment and can aid in optimization of processes to maximize or minimize tar production. Predictions of the rate at which products are instantaneously released from a single wood pellet are also in agreement with experiment. This capability is important for combustion modelling and gasifier simulation. The study provides both extensive data and a fundamental modelling approach that will enhance understanding of the effects of physical properties and processes on the chemistry of devolatilizing biomass. The work emphasizes the need for information both on char deposition rates during carbonization of a range of fuel types and on char thermal properties over a wide range of temperatures and porosities.  相似文献   
992.
Presents a model for psychological diagnosis and treatment of mental health disorders that is based on coping skills rather than on symptoms or pathologies. Coping skills, defined broadly as components of adaptability, are classified into 3 general areas: interpersonal relationships, thinking and feeling, and approaches to self and life. These 3 areas are further divided into 11 coping-skills categories. This model is intended to be applicable to all ages. It requires systematic assessment of an individual's current life situation in relation to that person's coping skills and coping-skills deficiencies. After such an assessment, interventions are directed toward assisting the individual to enhance appropriate coping skills. It is anticipated that this coping skills model may be used both independently and in conjunction with other diagnostic systems. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
The structure of three cross-linked polymers containing naphthalenic rings in their backbone structure was investigated by dynamic swelling and thermal analytic techniques. It was determined that the pyridine and n-proplyamine transport in microparticles (40 μm) of these polymers was non-Fickian, often approaching case II transport and sometimes even supercase II transport. The thermal analysis showed relatively stable structures up to about 350°C.  相似文献   
994.
995.
Rheumatoid arthritis (RA) patients have been identified as a medical population at risk for psychological disorder, largely because of the pain and functional disability that are the hallmarks of the disease. This study examined the degree to which self-reported functional disability and coping efforts contribute to psychological adjustment among adult RA patients over a 6-month period. Adaptive outcomes included maintaining a sense of worth, mastery, and positive affect despite the illness. Hierarchical multiple regression analyses indicated that increases in disability were related to decreased acceptance of illness and increased negative affect. Coping efforts were related to increases in positive affect. The findings provide modest support for the role individual coping efforts play in shaping illness-related outcomes. Although disability is not easily reversed, knowledge about coping strategies that moderate its psychological impact may provide a useful basis for designing psychological interventions to promote adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
Emotion regulation (ER) was assessed during a negative mood induction in 79 preschoolers who varied in degree of behavior problems. Facial expressivity during the induction was used to identify 3 ER groups: inexpressive, modulated expressive, and highly expressive. Group differences in ER were significantly related to heart rate and skin conductance. Inexpressive preschoolers had the highest heart rate, lowest vagal tone, and smallest autonomic nervous system (ANS) change during the induction. Highly expressive preschoolers had the slowest heart rate, highest vagal tone, and largest ANS change. The inexpressive and highly expressive groups had more externalizing symptoms than the modulated group at preschool age and at follow-up at the end of 1st grade. Inexpressive preschoolers appeared to have more depressed and anxious symptoms at follow-up. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
998.
Psychologists working with young gay men and lesbians may experience public and agency resistance based primarily on the confusion of moral and rational thinking and on homophobia. To work effectively with young lesbians and gay men, psychologists need to be relatively free of homophobia and knowledgeable about gay male and lesbian life-styles. Provision of developmental process information to the client is very useful. Internal and external homophobia, a lack of healthful role models, coming out to oneself and others, and AIDS (acquired immune deficiency syndrome) are among the most critical problems faced by young gay men and lesbians. Although a discussion of intervention techniques is beyond the scope of this article, bibliotherapy is briefly described as one effective intervention in that it provides necessary information to the client and it serves as a springboard for therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
Proposes a motivational analysis to help account for individual (e.g., sex) differences in different academic areas (e.g., mathematical vs verbal areas). It is proposed that certain academic areas (e.g., mathematics) are more likely than others (e.g., verbal) to pose difficulties at the start of new units and that the necessity of surmounting difficulties favors certain achievement orientations. To test the hypothesis that children's academic orientations interact with the acquisition demands of academic material to determine performance, 57 male and 37 female 5th graders, who were classified as helpless or mastery oriented on the basis of their attributions, were assigned to 1 of 2 learning conditions. One condition involved programmed confusion during learning, while the other was a no-confusion condition. When the learning task contained somewhat confusing material in the initial sections (even though it was irrelevant to what was to be learned), Ss with a mastery oriented attributional style significantly outperformed those with a helpless style. However, when the identical task was presented without the confusing material, both groups learned with equal facility. Results support the notion that achievement differences can result from the fit between children's achievement orientations and the demands of particular skill areas. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
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