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981.
陈蓓 《苏州科技学院学报(工程技术版)》2002,15(4):54-57
进入工业社会以来,人与自然的关系逐渐变为敌对排斥的关系,越来越多的人希望能恢复与自然的和谐。从多种学科的角度出发,阐明了生态城市的历史渊源、含义以及建立生态城市的重要性和可采取的方针策略。 相似文献
982.
983.
Comparison of lantadenes content and toxicity of different taxa of the lantana plant 总被引:1,自引:0,他引:1
Three taxa of the lantana plant (Lantana camara var.Aculeata) I (white-pink), II (yellow-pink), and III (yellow-red)-differed in the content of lantadenes and compounds X, Y, and Z. Lantadene A, lantadene B, and lantadene C were the major lantadenes of taxon III. It contained small amounts of lantadene D. Taxa I and II contained very small amounts of lantadene A and lantadene B. Compounds X, Y, and Z were the major constituents of taxa I and II, and they constituted 59% and 92% of the total constituents in these taxa, respectively. Ingestion of lantana leaf powder of taxon III by male guinea pigs caused severe hepatotoxicity. Taxon I elicited mild hepatotoxicity in one out of six animals while taxon II was nontoxic. The biological and ecological significance of the presence of high amounts of compounds X, Y, and Z in taxa I and n is not known. 相似文献
984.
Ecological footprints and sustainable urban form 总被引:5,自引:0,他引:5
Erling Holden 《Journal of Housing and the Built Environment》2004,19(1):91-109
This paper presents the results of a four-yearresearch project (1997–2001) entitled `Housingas a basis for sustainable consumption'. Theoverall aim was to obtain more empirical andtheoretical knowledge about the connectionbetween physical urban planning and householdconsumption. This knowledge provides a platformfor discussing principles and practices forsustainable urban development.This project was based on two main assumptions.First, it was suggested that the significantand increasing environmental damage due toprivate household consumption presents a majorchallenge in achieving sustainable development.Second, a large part of this consumption appears to be influenced by our physical livingsituation, i.e., the way we design and locateour houses. This also applies to energy use forheating and technical appliances, transport,and even to the considerable amount ofequipment that is needed for householdoperation, redecoration and maintenance. Withrespect to transport, the study team includedboth everyday travel and leisure-time journeysin this research. While everyday trips such astravelling to work, shopping and taking thechildren to school are strongly influenced bythe living situation of the household, thismight also be true for leisure-time travel.Based on two large surveys in the Norwegiantowns of Greater Oslo and Førde, the studyteam collected data on housing-relatedconsumption from 537 households. Ecological Footprinting was then used asan analytical tool to analyse the environmentalconsequences of this consumption. Theseecological footprint analyses suggest thatsustainable urban development points towardsdecentralized concentration, i.e.,relatively small cities with a high density andshort distances between the houses andpublic/private services. 相似文献
985.
柘林水利工程的防洪效益——从1998年洪水调度谈柘林水库在防洪中的作用 总被引:1,自引:0,他引:1
1998年柘林水库发生了建库以来的最大洪水,库水位2次超历史纪录,在江西省防总、江西省电力工业局防办的科学调度与决策下,取得了抗洪抢险的全面胜利,保住了京九铁路、郭东堤、永北围堤、昌九高速公路,柘林水库的防洪效益得到了充分的发挥,取得了巨大的经济效益和社会效益. 相似文献
986.
湟水干流西宁~民和段河道生态基流量研究 总被引:1,自引:0,他引:1
李万寿 《水资源与水工程学报》2007,18(3):75-79
湟水是青海省地表水利用率最高的河流,湟水干流西宁~民和段也是青海省水污染最严重的河段之一。本文以乐都水文站和民和水文站断面为控制节点,利用实测水文资料,通过历史水文资料法,初步确定西宁~民和段河段生态基流量为4.55 m3/s。这将为湟水中下游水资源可持续利用的管理目标提供了现实途径,具有现实意义。 相似文献
987.
龙羊峡水库投运以来,遭遇到了罕见的连续枯水年,电网在获得“水火互浊”便得的同时,更经受了水电站“靠天吃饭”所造成的困难,通过分析天然径流及水库特性,对近年来的水库调度作了初步总结和分析,论述了水库调度方法必须要适应水库性能,对龙羊峡,刘家峡两水库进行联合调度必须以水库调度图为基本依据,电网及其他部位的用水要服从水库设计规定,以保持水库的正常运行状态。 相似文献
988.
989.
Naar-King Sylvie; Podolski Cheryl-Lynn; Ellis Deborah A.; Frey Maureen A.; Templin Thomas 《Canadian Metallurgical Quarterly》2006,74(4):785
In this study, the authors tested a social ecological model of illness management in high-risk, urban adolescents with Type 1 diabetes. It was hypothesized that management behaviors would be associated with individual adolescent characteristics as well as family, peer, and provider relationships. Questionnaires were collected from 96 adolescents in poor metabolic control and their primary caregivers. Variables in each system were correlated with illness management. Multiple regression demonstrated that higher externalizing symptoms, poorer family relationships, lower satisfaction with providers, and greater age contributed to the variance in illness management. Internalizing symptoms and peer relationships were no longer significant in the model. Results support a social ecological model of illness management in high-risk youths. Interventions grounded in social ecological theory are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
990.
数据仓库技术及其在防洪调度智能决策支持系统中的应用 总被引:3,自引:0,他引:3
针对防洪调度智能决策支特系统(FCDIDSS)的数据特性,探讨了一种决策支持新技术─—数据仓库技术在防洪调度智能决策支持系统中的应用,提出了应用数据仓库技术的FCDIDSS的数据组织、应用接口设计和实现方法. 相似文献