Determining thermal properties of gypsum board at elevated temperatures

The National Institute of Standards and Technology (NIST) and the Center for Better Living have formed a collaboration to assess the performance and failure mechanisms of gypsum wall assemblies under real fires/furnace conditions. These measurements are being used to compile an experimental database necessary to validate models that could be used to predict their performance and ultimate failure under various design fires. A critical component of the database is thermal property data of gypsum board. The present paper describes the results of an effort to quantify thermal properties of gypsum board. The thermal conductivity specific heat mass loss and linear contraction for gypsum board types widely used in the U.S.A. and Japan were measured both at room temperature and at elevated temperatures. The gypsum board types tested include Type X and Type C from the U.S.A. and Type R and Type F from Japan. Results indicate that the difference in thermal properties of all gypsum board samples tested in the present study is not significant particularly at elevated temperatures. A large difference in linear contraction among gypsum board samples was observed at elevated temperatures, implying a significant difference in mechanical behavior at fire temperatures. The experimental data set provides valuable information that can be used to model the behavior of gypsum board at elevated temperatures. Copyright © 2009 John Wiley & Sons, Ltd.     

CDMA运营商提供无线数据业务的解决方案

由于移动设备价格几乎每天都在下降，并且无线数据网络也以同样速度变得更快捷、更便宜，移动数据业大张旗鼓扩张的条件已经形成，业界分析人士认为无线数据的应用正在形成高潮。总部位于波士顿的Yankee集团公司指出：到2002年，北美移动数据用户的数量将增长两倍，即从今天的338万用户上升至1064万用户。国际数据公司预测：使用移动电话接收数据的人数所占比例在同期将从万％攀升至700fo。为此，无线服务提供商正在增加新型增值移动数据业务以满足需求。码分多址（CDMA）服务提供商现已开始提供数据业务，其中一些提供商将扩展其服务范围，成为无线因特网服务提供商（ISP）或者是为移动用户提供公司虚拟专用网（VPN）。这样移动用户就可享受诸如万维网测览、电子邮件、传真和公司内联网访问等便捷。3Corn公司提供了针对CDMA网络的IWF系统，它不仅是向移动用户提供电路交换数据的一个解决方案，而且也是在无线CDMA网络和有线公共交换电话网络（PSTM）之间实现桥接的一个完整系统。IWF系统基于3Corn公司的获奖产品TotalControl多服务访问平台，允许CDMA运营商向无线用户提供基于电路交换的数据和传真服务。借助系统的快速网...     

Elucidation of the electrochromic mechanism of nanostructured iron oxides films

Nanostructured hematite thin films were electrochemically cycled in an aqueous solution of LiOH. Through optical, structural, morphological, and magnetic measurements, the coloration mechanism of electrochromic iron oxide thin films was elucidated. The conditions for double or single electrochromic behavior are given in this work. During the electrochemical cycling, it was found that topotactic transformations of hexagonal crystal structures are favored; i.e. α-Fe₂O₃ to Fe(OH)₂ and subsequently to δ-FeOOH. These topotactic redox reactions are responsible for color changes of iron oxide films.     

The quest for alternatives to microbial cellulase mix production: corn stover‐produced heterologous multi‐cellulases readily deconstruct lignocellulosic biomass into fermentable sugars

BACKGROUND: Production of cellulosic ethanol is still expensive compared with corn (maize) grain ethanol due to the high costs of bulk production of microbial cellulases. At least three cellulases including endo‐cellulase, exo‐cellulase and cellobiase are needed to convert cellulosic biomass into fermentable sugars. All these cellulases could be self‐produced within cells of transgenic bio‐energy crops. The production of heterologous Acidothermus cellulolyticus (E1) endo‐cellulase in endoplasmic reticulum and mitochondria of green tissues of transgenic corn plants was recently reported, and it was confirmed that the heterologous E1 converts cellulose into fermentable sugars. RESULTS: Biologically active A. cellulolyticus E1, Trichoderma reesei 1,4‐β‐cellobiohydrolases I (CBH I) exo‐cellulase and bovine rumen Butyrivibrio fibrisolvens cellobiase were expressed in corn plant endoplasmic reticulum (ER), apoplast (cell wall areas) and vacuole respectively. Results show that the ratio 1:4:1 (E1:CBH I:cellobiase) of crude heterologous cellulases is ideal for converting ammonia fiber explosion (AFEX) pretreated corn stover into fermentable sugars. CONCLUSIONS: Corn plants that express all three biologically active heterologous cellulases within their cellulosic biomass to facilitate conversion of pretreated corn stover into fermentable sugars is a step forward in the quest for alternatives to the present microbial cellulase mix production for cellulosic biofuels. Copyright © 2011 Society of Chemical Industry     

Age of onset of first alcohol intoxication and subsequent alcohol use among urban American Indian adolescents.

The objective was to assess the effect of early onset intoxication on subsequent alcohol involvement among urban American Indian youth. The data come from the American Indian Research (AIR) project, a panel study of urban Indian youth residing in King County, Washington. Data were collected annually from the adolescent and his/her primary caregiver from the 1988–89 school year to the 1996–97 school year, providing a total of nine waves of data. Early intoxication (by age 14) was related to delinquency, family history of alcohol abuse or dependence, poverty, broken family structure, less family cohesiveness, and more family conflict. The effects of these characteristics were, therefore, partialed out in testing effects of early intoxication on later alcohol involvement. Two-part latent growth models of alcohol use and alcohol problems were specified. Effects of early onset intoxication on these trajectories, as well as lifetime alcohol abuse or dependence by the transition to young adulthood, were examined. Findings indicate that adolescents who experienced their first intoxication early (by age 14), used alcohol more heavily from the ages of 16 to 18, experienced more problems related to the alcohol's use from the ages of 16 to 18, and were more likely to have a diagnosed alcohol disorder by the final wave of data collection. Congruent with similar studies in the general population, early intoxication appears to be associated with a deleterious course of alcohol involvement during adolescence and into the transition to young adulthood among urban American Indian youth. Implications for prevention are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The single practitioner and community engagement: Bridging the gap between practice and social action.

Urban communities, with their myriad systemic problems of poverty, social dysfunction, and diminishing public and private resources compounded by endemic health and economic disparities, provide the single psychologist practitioner with a rewarding opportunity to become involved in urban community activities and to make a positive impact. Finding common ground for discourse and action with community members can benefit both the community and the psychologist by helping them to identify, understand, and engage the community in developing solutions for community-based problems faced by residents on a daily basis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Manikin test for flame engulfment evaluation of protective clothing: Historical review and development of a new ISO standard

The overall performance of a firefighter turnout suit can only be evaluated using both bench‐scale tests and an assessment based on an instrumented manikin under defined, close to real‐life conditions in a laboratory. Using manikins in rating protective clothing has already a long history which will be reflected in this paper. Efforts all over the world to reproduce a flame engulfment situation in a laboratory are currently being combined in a new draft international standard (ISO/DIS 13506.3). A round robin test showed an acceptable reproducibility for this method based on a manikin test and a gas burner system. An overview of existing measurement systems and the results of this round robin are discussed and possible improvements for the standard flame engulfment test method are proposed. Copyright © 2006 John Wiley & Sons, Ltd.     

Moral credentials and the expression of prejudice.

Three experiments supported the hypothesis that people are more willing to express attitudes that could be viewed as prejudiced when their past behavior has established their credentials as nonprejudiced persons. In Study 1, participants given the opportunity to disagree with blatantly sexist statements were later more willing to favor a man for a stereotypically male job. In Study 2, participants who first had the opportunity to select a member of a stereotyped group (a woman or an African American) for a category-neutral job were more likely to reject a member of that group for a job stereotypically suited for majority members. In Study 3, participants who had established credentials as nonprejudiced persons revealed a greater willingness to express a politically incorrect opinion even when the audience was unaware of their credentials. The general conditions under which people feel licensed to act on illicit motives are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The norm of self-interest and its effects on social action.

Four studies investigated whether people feel inhibited from engaging in social action incongruent with their apparent self-interest. Participants in Study 1 predicted that they would be evaluated negatively were they to take action on behalf of a cause in which they had no stake or in which they had a stake but held stake-incongruent attitudes. Participants in Study 2 reported both surprise and anger when a target person took action on behalf of a cause in which he or she had no stake or in which he or she held stake-incongruent attitudes. In Study 3, individuals felt more comfortable engaging in social action and expected others to respond more favorably toward their actions if the issue was described as more relevant to their own sex than to the opposite sex. In Study 4, the authors found that providing nonvested individuals with psychological standing rendered them as likely as vested individuals to undertake social action. The authors discuss the implications of these results for the relationship between vested interest, social action, and attitude–behavior consistency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

TPV cell IV curve testing with varying black body emission temperatures, intensities, and cell temperatures

A TPV GaSb cell was tested as part of the first effort to establish a standard method of characterizing such cells. Cell current/voltage (IV) curves were measured at different cell temperatures using black body radiation at various emission temperatures and intensities. The results of the effects on performance are briefly analyzed and include temperature coefficients, voltage/intensity coefficient, and response to spectral shift.