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991.
Abstract

This review focuses on physico-chemical aspects of cyclopentene-fused polycyclic aromatic hydrocarbons (CPAH) that we are currently studying. Steric effects, deformation of polycyclic skeletons from planarity, radical ions, and excited states are properties being investigated. Molecular modeling as a tool for predicting the geometries of CPAH is discussed.  相似文献   
992.
In two studies, the authors sought to identify the mathematical function underlying the temporal course of forgiveness. A logarithmic model outperformed linear, exponential, power, hyperbolic, and exponential-power models. The logarithmic function implies a psychological process yielding diminishing returns, corresponds to the Weber-Fechner law, and is functionally similar to the power law underlying the psychophysical function (Stevens, 1971) and the forgetting function (Wixted & Ebbesen, 1997). By 3 months after their transgressions, the typical participant's forgiveness had increased by two log-odds units. Individual differences in rates of change were correlated with robust predictors of forgiveness. Consistent with evolutionary theorizing (McCullough, 2008), Study 2 revealed that forgiveness was uniquely associated with participants' perceptions that their relationships with their offenders retained value. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
We demonstrated an efficient surface pretreatment with excimer laser at 193 nm, which could be successfully used as a surface preparation tool to improve the adhesion and mechanical properties of bonded polymer joints. The effect of the ultraviolet (UV) light can be used both as a method for increasing the specific surface area improving the mechanical adhesion and as a method for activating the polymer surface improving the physical adhesion. Mechanical tests and studies on the failure of bonded polycarbonate (PC) and polyetheretherketone (PEEK) samples showed a significant increase in the quality of bonded connections by using pretreatment with UV laser. As a result of the studies, the bond strength of the PC samples was increased by about 32% using a PB437 UV curing adhesive. By using Loctite 9466 applied to PEEK samples, a strength increase of about 36% was achieved.  相似文献   
994.
995.
A wide variety of binary systems has been produced in Ti and Zr with compositions controlled to depths up to 1000 Å by means of ion implantation. Thermal oxidation of these specimens has led to models for the oxidation process which are consistent with previous ideas but involve more explicitly the crystallographic properties of the two oxides. Novel atomic migration effects, away from the implanted layer, have been observed in Ti and explained in terms of linear short-circuit diffusion.  相似文献   
996.
The relationship between user participation and information system (IS) success has drawn attention from researchers for some time. It is assumed that strong participation of future users in the design of IS would lead to successful outcomes in terms of more IS usage, greater user acceptance, and increased user satisfaction. However, in spite of this, much of the empirical research so far has been unable to demonstrate its benefits. This paper examines the participation–success relationship in a broader context, where the effects of user participation and two other factors, user attitudes and user involvement, on system success occur simultaneously. Other contingency variables considered here are: system impact, system complexity, and development methodology. The theoretical framework and the associated hypotheses are empirically tested by a survey of 32 organizations. Empirical results corroborate the positive link between user participation and user satisfaction and provide evidence on the interplay between user attitudes and user involvement.  相似文献   
997.
Objective: To study posttraumatic growth and psychological and physical well-being among 25 cancer survivors (12 men, 13 women) 9 years after receiving a hematopoietic stem cell transplant from an unrelated donor. Measures: Participants completed measures of well-being (e.g., depression, physical function) and posttraumatic growth at the 9-year follow-up. Prior to treatment, optimism, social support, and well-being had been assessed. Results: Findings reveal high levels of physical and psychological well-being. Survivors reported posttraumatic growth in several domains, including increased personal strengths and enhanced interpersonal relationships. Higher levels of growth were significantly related to gender and age: Women reported more total posttraumatic growth, and older survivors reported more enhanced spirituality, one domain of growth. Posttraumatic growth and well-being after treatment were predicted by 2 psychosocial variables assessed prior to treatment: dispositional optimism and social support. Implications: Although long-term survivors report ongoing physical limitations, they also experience well-being in both physical and psychological domains. Posttraumatic growth is an area of well-being deserving of additional research and clinical attention. In particular, there may be reason to assist survivors to articulate growth as part of ongoing care. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
This paper develops a relatively simple model that is intended to rapidly evaluate design configuration and operating conditions for tubular anode-supported solid-oxide fuel-cell (SOFC) stacks. Heat is removed from the SOFC tubes by a combination of convection and radiation. Heat is convected to air that circulates outside the SOFC tubes and radiated to a surrounding cylindrical wall. The tubes are assumed to be arranged in hexagonal arrays in which the distance between tubes centers form equilateral triangles. The paper presents new configuration-factor formulas that are needed to represent arrays of staggered cylinders. The configuration factors are derived for long cylinders using the crossed-string method. These configuration factors have general utility beyond the application to fuel-cell systems. The model is applied to a particular cell and stack system and used to evaluate the effects of a range of design and operating conditions.  相似文献   
999.
Objective: To investigate the influence of population heterogeneity among geriatric patients on the factor structure and differential item functioning on the Functional Independence Measure (FIM) and thereby evaluate the appropriateness of using 2 factor composite scores (FIM motor and FIM cognition) among geriatric patients. Design: A specific application of structural equation modeling (i.e., multiple indicators, multiple causes [MIMIC] model) was conducted on FIM admission scores from 718 geriatric rehabilitation patients. Setting: A large urban rehabilitation hospital. Participants: 718 inpatients referred for medical rehabilitation (M?=?77.5 yrs; 62% African American; 68% female). Measurements: All participants' functional abilities were rated on the FIM by trained physical and occupational therapists on admission to the rehabilitation hospital. In addition, all patients completed the Geriatric Depression Scale. Results: Three motor functioning items and 3 cognitive functioning items differed systematically across groups within this geriatric sample (i.e., young-old vs old-old, male vs female, depressed vs nondepressed) even after controlling for group differences on levels of overall motor and cognitive functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Following a natural disaster, access to safe drinking water by the affected population is a high priority. Low cost water purification systems, which can be used for both short-term (immediate) and long-term (sustainable) response to serve the needs of the affected communities, are ideal for these scenarios. The University of Hawaii has developed three low cost water purification technologies for use during humanitarian assistance and disaster relief (HA/DR) missions. A UH team participated in joint USA and partner nation training exercises, such as Crimson Viper 2010 and 2011, organized by the Marine Corps Forces Pacific Experimentation Center (MEC) in Sattahip, Thailand, to demonstrate the effectiveness of these technologies to purify water from local sources. Three technologies were selected for Crimson Viper 2010: (1) a backpack filter unit, (2) a bicycle pump powered reverse osmosis (RO) unit, and (3) a model slow sand filtration unit. For Crimson Viper 2011, improved versions of the backpack and RO units were deployed. This article discusses and evaluates the results obtained during the demonstration of the three technologies at these exercises.  相似文献   
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