大气污染治理的“兰州经验”——基于环境保护与国家治理现代化的考察

近年来,我国大气污染防治工作取得了一定成效,但大气环境整体形势仍然十分严峻,如何防治大气污染成为政府和人民高度重视的问题。兰州市在大气污染治理工作取得了瞩目的效果并在治理活动中形成了丰富的经验,大气污染治理的"兰州经验"为环境治理以及国家治理现代化树立了一个可资借鉴的样板。针对生态文明建设过程中的难题,兰州市在大气污染治理过程中较好地了协调经济发展和环境保护之间的关系,抓住了完善能源结构和产业结构调整这一核心环节。更为重要的是,"兰州经验"体现了国家治理现代化的公共性、共治性以及有效性的核心价值理念,突显了国家治理体系和治理能力现代化的重要价值。在切实有效的权力运行机制保障下,兰州市在环境治理工作中运用了法治思维和法治方法,以坚强的执行力确保工作实效,同时还实现了广泛的社会参与,使得治理模式更为科学与民主。     

Induction of host specificity in larvae of Manduca sexta: chemical dependence controlling host recognition and developmental rate

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     

农村联户沼气工程可行性研究及经验——以浙江省江山市淤头镇为例

以浙江省江山市淤头镇联户沼气工程为例,从经济、技术及社会可行性三方面进行具体分析,指出联户沼气相比户用沼气具有规模经济效益显著、资金支持渠道多、管理便利、农户满意度高、技术和市场创新空间大等突出优势,可为联户沼气工程推广提供经验借鉴。     

体验经济时代下体验旅游产品开发策略

随着人们生活水平的提高,体验经济时代的来临,人们正进入体验消费时代,游客期望的是通过自身参与而得到难忘的整体旅游体验。结合体验旅游产品的涵义及其开发中存在的问题,分析了体验旅游产品的开发原则,从个性化、文化性、绿色产品等方面探讨体验旅游产品的开发策略具有重要的意义。     

民族村寨游客的旅游体验质量研究——以西双版纳傣族园为例

目前国内对旅游体验和体验旅游的研究大多停留在理论研究层面。针对这一情况,以西双版纳傣族园游客为对象进行了实地问卷调查,采用社会统计学基本原理探索性地对游客的旅游体验质量进行了定量评价。结果表明,加强民族村寨的个性化体验旅游产品开发和民族文化旅游资源保护对少数民族地区旅游业的可持续发展具有重要的现实意义。     

国外农村生活污水分散治理管理经验的启示

总结了在农村生活污水处理上日本的成功经验和新西兰的探索实践,提出我国今后推广农村生活污水治理要确定治理范围,制定相应的技术标准,明确强制性责任,建立专业化服务体系和信息平台。     

When mobility makes sense: A qualitative and longitudinal study of the daily mobility of the elderly

A majority of North Americans hopes to grow old in the suburbs. This aspiration depends upon their ability to drive and their access to a car. Because it is essential for everyday travel, car-mobility in the suburbs is becoming a symbolic goal. The meanings of mobility for elderly will evolve over time, notably as a result of changes in autonomy. However, the mobility of older adults is mainly understood in terms of daily trips. Little research has considered the temporal dimension of aging as an evolving process. This study aimed at understanding with a qualitative and longitudinal perspective how older people stay (auto-)mobile in their house and their neighborhood against the need to adapt to reduced autonomy and mobility over time. A group of 22 suburbanites aged from 62 to 89 was interviewed in 1999 and in 2006. The results show that even if older people succeed in increasing their mobility, they are headed for inevitable immobility. Among the environmental adaptation strategies that were observed, the constructed behaviors, the dependencies demanding additional supports as well as the social life modulate different evolving experiences of the city: the shrinking city, the fragmented city, and the city by proxy. The built environment is at the heart of a complex process in which the adaptation of mobility contributes to the emergence of new residential experiences.     

氧化沟在汽车工业小区污水处理上的应用

根据汽车城工业污水水质特点,采用水解酸化氧化沟处理工艺,出水水质确保达到二级排放标准,设计上尽量按一级排放标准考虑。该文主要阐述氧化沟工艺的特点以及污水厂设计参数选择和一些体会。     

哈尔滨市政排水现状调查与发展对策分析

文章对哈尔滨市市政排水设施状况进了详细调查与研究,总结出“科学规划、合理布局,逐步完善排水基础设施;分步实施、重点突破,积极推进合流制排水系统改造;强化管理、科技创新,稳步提高现有排水设施的利用率”等管理经验。指出哈尔滨市排水建设与管理中存在的突出问题,并从建设资金来源、法制化管理、污泥处理设施规划建设以及建立路网改造与排水管网建设协调配合机制、加大排水管网建设力度等方面提出对策。     

北京市生态环保建设经验对南京的借鉴

北京以举办奥运为契机,全面改善了环境质量,兑现了“绿色奥运”的庄严承诺。后奥运期间,北京继续实施了一系列环境保护行动计划,大力推进生态文明建设,“绿色奥运”成果得到巩固提升。借鉴北京成功的做法和经验,特提出南京环境保护和生态建设的对策建议。