Retrieving leaf area index for coniferous forest in Xingguo County, China with Landsat ETM+ images

Spatial distributions of the leaf area index (LAI) needed for carbon cycle modeling in Xingguo County, China were estimated based on correlations between the field-measurements and vegetation indices (VIs). After making geometric and atmospheric corrections to two Landsat ETM+ images, one in January 2000 and the other in May 2003, three VIs (SR, NDVI, and RSR) were derived, and their separate correlations with ground LAI measurements were established. The correlation with RSR was the highest among the three VIs. The retrieved LAI values for January 2000 were lower than those for May 2003 because of a small seasonal variation in the coniferous forests (predominantly masson pine) and the decrease in the understorey vegetation during winter.     

Embryonic and fetal globins are expressed in adult erythroid progenitor cells and in erythroid cell cultures

The understanding of human hemoglobin ontogeny during development is of biological and clinical importance. Molecular and immunocytological techniques were used to study the expression of embryonic zeta (ζ), epsilon (ε), and fetal gamma (γ) globin genes in newborn cord blood, peripheral blood from men, pregnant and non-pregnant women, and in vitro mononuclear cell cultures. We have shown that embryonic and fetal globin mRNA and peptides are expressed in cultured erythroid cells and in circulating blood cells from newborns, adult non-pregnant women and from men. The findings suggest that during erythroid cell differentiation in newborns and adults, there is a transient recapitulation of sequential globin chain expression as found during embryonic and fetal development. Furthermore, these findings underscore the need for caution in using embryonic and fetal globin chains as markers to identify erythroid cells of fetal origin in maternal circulation for prenatal diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.     

企业突发环境事件应急预案编制的实践和思考

近年来,突发环境事件层出不穷,为减轻突发环境事件带来的损害,我国已建立突发环境事件应急预案制度,但企业突发环境事件应急预案编制工作尚不完善。目前企业突发环境事件应急预案编制实践过程中仍存在着不少问题,这些问题的存在,限制了应急预案在应急管理中能发挥的作用。因此应急预案编制过程中的问题,亟需完善,实践中可从多个角度出发完善应急预案的编制工作。     

我国旅游安全评价研究现状与展望

旅游安全评价研究已经成为旅游安全研究的重要领域。为了解和掌握我国旅游安全评价研究的进展,从相关理论基础、评价对象、评价指标体系、权重系数以及评价方法等方面对其进行了梳理和分析。旅游安全评价总体发展迅速并逐年向好,初步形成了以事故致因为导向的理论框架,评价对象主要集中在旅游地系统和旅游生态方面,评价指标体系研究初见成效,主观权重研究较多、客观权重研究少,评价方法研究简单应用多、改进创新少。最后,根据文献分析结果和我国旅游安全评价发展趋势,结合旅游科学和安全科学知识对旅游安全评价未来的研究方向进行了展望。     

湖南环境应急指挥系统结构与功能浅析探讨

近年来,湖南省环境信息化建设快速发展,但在通信网络的抗毁性以及突发事件的应对能力等方面考虑还不够完善。环境应急指挥系统能够协助环境厅应对各类突发的紧急事件,实现事前监测;在应急事件发生的时候快速、准确、科学地决策、协调、调度和指挥,向公众提供环境方面的紧急救助信息和服务;事后进行事件评估,重建等工作。本文研究的是湖南省环境应急指挥系统功能的实现,完成了一套环境应急指挥系统的开发工作。根据目前我省环境保护应急指挥实际情况,设计了环境应急指挥系统的总体平台;对环境应急指挥调度系统和综合应用系统进行了设计和分析,重点是对应用软件系统和硬件支撑平台进行了研究设计。     

油品脱酸工艺研究进展

综述了国内外油品脱酸技术发展历程和研究现状,分析了各种技术工艺的优点和不足,随着环保、节能减排思想的深入,新的绿色脱酸分离技术将是以后发展的主要趋势。     

火电厂烟气脱硝技术探析

介绍了烟气脱硝技术中的选择性催化还原技术SCR、选择性非催化还原技术SNCR以及混合型SNCR-SCR三种工艺。在比较三种工艺的基础上得出前两者工艺的优势和不足以及当前火电厂使用SNCR-SCR混合型烟气脱硝技术较多的原因所在。