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21.
Abstract

Fullerene Science and Technology, both the field and the journal, have observed considerable progress during the last few years. The field has continued to mature as witnessed by the many new and interesting results published in thousands of journal articles (1-3) and in a multitude of books and conference proceedings. The recognition of fullerene sciences as a self-containing field of research has been culminating in the awarding of the 1996 Chemistry Nobel Prize to Professors Robert S. Curl, Harold W. Kroto, and Richard E. Smailey.  相似文献   
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FE micro-models have been developed in order to determine contact, stress and strain conditions produced by a steel asperity sliding on the surface of a normally oriented fibre-reinforced polymer composite. A displacement coupling technique was introduced to model a micro-environment as part of a macro-environment and to get more realistic simulation results about the failure conditions in the composite structure, in comparison to the so far widely applied anisotropic analytical or numerical macro-models. On the basis of the results, conclusions may be drawn for the possible wear mechanisms of the fibre-reinforced polymer composite. Stress results in the vicinity of the fibers in the contact area show high shear loading of the matrix leading to the formation of stretched-out matrix wear debris. In addition, high repeated compression-tension stresses at the fibre/matrix interface near the surface can lead to fibre debonding phenomena. Considering the fibre ends in the contact region, high compression stresses at their rear edges can produce fibre cracking features. To study the wear mechanisms experimentally, a single asperity scratch test was also performed showing shear failure events of the polymer matrix, fibre/matrix debonding and fibre cracking effects, as expected from the modelling studies.  相似文献   
24.
Prior research has shown that young refugees may be especially traumatised. The study includes 123 young Bosnian refugees, living at two Bosnian boarding-schools in Denmark who were given a revised version of the Harvard Trauma Questionnaire (HTQ). The subjects themselves have on average experienced seven traumatic events, and have either witnessed or had a family member experience an additional six events. Three-quarters have been shot at, have lost their homes and private possession and have been exposed to violence in the form of harassment or humiliation. Two-thirds have lost friends. Three-fifths have lived with uncertainty as to whether friends and family were alive or dead. More than half have seen dead and wounded people, have had their lives threatened and have thought that they would die. More than a third have lost close family members, have been wounded and have had their homes destroyed. Just under a third have been exposed to physical violence or have witnessed somebody being killed. A quarter have starved and been ill without being able to receive treatment. About a fifth have experienced captivity, torture and forced labour. 6% have been raped or exposed to other forms of sexual abuse. It is concluded that the young Bosnians examined are a multitraumatised group. Use of the HTQ increased the number of traumatic events quite considerably compared to the case notes.  相似文献   
25.
Editorial     
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We present the Vienna Schrödinger-Poisson Solver (VSP), a multi-purpose quantum mechanical solver for investigations on nano-scaled device structures. VSP includes a quantum mechanical solver for closed as well as open boundary problems on fairly arbitrary one-dimensional cross sections within the effective mass framework. For investigations on novel gate dielectrics VSP holds models for bulk and interface trap charges, and direct and trap assisted tunneling. Hetero-structured semiconductor devices, like resonant tunneling diodes (RTD), can be treated within the closed boundary model for quick estimation of resonant energy levels. The open boundary model allows evaluation of current voltage characteristics.  相似文献   
28.
This new combined optical–wireless indoor communication system provides an economic and flexible approach for local area networks mainly in large buildings or in a group of several buildings. The radiation from the radio base stations of mobile networks cannot penetrate into large buildings completely. That problem is more serious at higher frequencies. The present approach offers a good solution to this problem. In this approach the wireless communication serves small picocells which are interconnected by an optical backbone. The performance of the system is enhanced by assigning a specific radio frequency for each picocell which enables the transmission of the wireless channels without altering their modulation formats. This method allows for a simple, and low-cost indoor communication system.  相似文献   
29.
We present a comparison of models describing the pyrolytic deposition of SiO2 with a low pressure chemical vapor deposition process. In order to meet industrial simulation requirements, e.g. accuracy and fast delivery of results, we present an overview of established and new models, their use within TCAD applications, and their best results which have been obtained by calibrations according to SEM measurements.  相似文献   
30.
This study examined the influence of smoking cues and nicotine deprivation on responses to alcohol among hazardous drinkers. Fifty-six daily smoking, hazardous drinkers were exposed to either smoking cues or control cues after either 6 hr of nicotine deprivation or no deprivation. Urges to drink alcohol, alcohol-related cognitive processing, and alcohol consumption were assessed after cue exposure. Results indicated that nicotine deprivation increased urges to drink, the accessibility of alcohol outcome expectancies, and the volume of alcohol consumed. There was little influence of the smoking cue manipulation on these processes. Implications for understanding the mechanisms underlying alcohol–tobacco interactions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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