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101.
本文以日本为例总结了国外社区防灾减灾经验以及对我国的启示。主要包括:完善社区减灾法律制度,制定社区防灾计划,制定社区灾害风险图,建设社区防灾无线网络和普及防灾减灾知识,重视企业参与防灾减灾活动。  相似文献   
102.
Summary. The tobacco hornworm, Manduca sexta L. (Lepidoptera: Sphingidae) is a specialist on Solanaceae. This host specificity is induced as the larva feeds on solanaceous foliage, so that solanaceous-reared larvae will refuse to feed on other plants. Experiments were designed to determine the role of dietary constituents on the induction of host specificity and the effects of these on development of M. sexta. Choice assays using leaf discs of cowpea, Vigna sinensis (Fabaceae), were used to monitor the isolation of relevant chemical cues from foliage of potato. An aqueous extract of potato foliage strongly stimulated feeding. This extract was partitioned with n-butanol under alkaline conditions to obtain a highly active butanol extract. Reversed phase flash chromatography with a water-methanol gradient gave an active fraction that was used as a supplement for wheat germ-based artificial diet. Larvae reared on this s-diet became dependent on potato allelochemicals for initiation and continuation of feeding activity. These larvae also developed faster than larvae reared on the control p-diet, but no effect on adult mass was detected. Further flash chromatography of the active fraction under alkaline conditions provided a highly active sub-fraction, and semi-preparative HPLC using gradients of water and acetonitrile resulted in the isolation of a single compound. Bioassays indicated that this compound alone can account for host recognition by solanaceous-reared larvae. The results suggest that the mechanism of induced host specificity in M. sexta involves development of dependence on this compound. Received 21 December 1999; accepted 14 March 2000  相似文献   
103.
简要介绍了一起医用90Sr放射源被盗事故的调查处理过程,分析了事故原因,总结了事故教训和处理经验。  相似文献   
104.
随着官媒时代的终结,以微信公众号为代表的新媒体的盛行,强烈地冲击着传统纸媒。微信公众号能够增加期刊与读者群之间的“粘性”,从而扩大期刊的学术影响力和社会知名度。在中国地理资源期刊网微信公众号的运行实践基础上,系统总结期刊微信融平台经营的实践与经验,并以《地理研究》等数据为例,阐述微信推送对期刊产生的综合作用,以期为科研微信融平台的运行提供指导和借鉴意义。研究结果表明:(1)科研微信融平台上生产好微推需遵守十四条原则、十一条创意要求;(2)坚持不懈地在微信公众号上发送消息,可以增加编辑与读者之间的交流、拓展读者范围、增加文章的下载量和被引量,从而树立学术期刊的品牌形象,提升期刊的学术影响力;(3)集群化的科研微信融平台的运行,一定要注意共同维护平台形象、谁制作谁负责、合理安排发文量和发文时间、个刊微平台实现互补等。持续地创意和推出微推,需要长期坚持,把期刊编辑和学术研究、移动互联时代、全媒体手段等积极“融”起来,实现期刊由传统纸质出版向富媒体出版、期刊由文献生产者向学科与社会集成型知识服务提供平台的两大根本性转型,才是期刊的根本出路。  相似文献   
105.
This article proposed and tested a multilevel and interactional model of individual innovation in which weekly moods represent a core construct between context, personality, and innovative work behavior. Adopting the circumplex model of affect, innovative work behavior is proposed as resulting from weekly positive and high‐activated mood. Furthermore, drawing on the Big Five model of personality and cognitive appraisal theory, openness to experience and support for innovation are proposed as individual and contextual variables, respectively, which interplay in this process. Openness to experience interacts with support for innovation leading to high‐activated positive mood. Furthermore, openness interacts with these feelings leading to greater levels of innovative work behavior. Overall, the model entails a moderated mediation process where weekly high‐activated positive mood represents a crucial variable for transforming contextual and individual resources into innovative outcomes. These propositions were tested and supported using a diary methodology and multilevel structural equation modeling, on the basis of 893 observations of innovative work behavior and moods nested in 10 weekly waves of data. This information was collected from 92 individuals of diverse occupations employed in 73 distinct companies. Theoretical and practical implications are discussed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
106.
沾益县截止2010年底完成了23.02万人饮水安全建设任务。总结了农村饮水安全建设经验,提出今后应加强建立良性管理机制,建立社会化服务保障体系,保护饮用水源,推广参与式模式,抓好农村人居环境整治和素质教育五方面建设。  相似文献   
107.
介绍了2004年日本新瀉中越地震及其余震的概况、震源机制和地震发生的特点,描述了普通民宅、大型公共设施、生命线工程和农林畜牧业的震害情况及震后日本政府的紧急救援措施,初步总结了抗震救灾工作的经验和教训,为我国今后这方面的工作提供参考.  相似文献   
108.
The Hydrologic Engineering Center (HEC-1) model was used to construct synthetic hydrographs for isolated interior urban floods. Flood peak and lag time were very well preserved in simulated flows. Total volume was not adequately expressed. Lag time varied inversely with both urban development and storm intensity. Peak discharge varied with storm intensity, but this variability was well defined only at very high urbanization levels. An 175% increase in storm intensity produced a change of about 15% in peak discharge. Claims for flood damage correlated well with estimates of peak flow and lag time combined. Other measures of flood experience also correlated with the two features. Within the range of storms utilized, urban development factors consistently outranked storm intensity as a determining factor in flood damage.  相似文献   
109.
The Recreation Opportunity Spectrum (ROS) system is used by the USDA Forest Service and USDI Bureau of Land Management for inventorying, classifying, and managing wildlands for recreation. Different ROS classes from the Colorado and Arkansas Rivers in Colorado were compared, using visitor survey data collected in 1979 and 1981, to see if the different classes offered different recreational experience opportunities. No difference between classes was found. Six possible reasons for not finding a difference are discussed. The usefulness of ROS at the broader levels of planning and the needs at more detailed levels of planning are noted.  相似文献   
110.
目前我国的生活垃圾中的再生资源回收利用率较高,再利用的过程基本是市场驱动的,但具有负外部性和不可持续性。应通过扩大生产者责任来重构循环利用体系,减少对环境的不利影响。本文在分析总结上海一次性饭盒回收利用经验的基础上,探讨了在我国推行扩大生产者责任制度的对策。  相似文献   
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