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131.
湖南参与了多个区域旅游合作战略,其中泛珠三角和中部6省合作战略是影响湖南旅游经济发展的两大重要外部力量,两大区域合作给湖南旅游业带来了新的发展机遇。在分析它们给湖南旅游发展带来发展机遇的基础上,提出了建立专门的行政组织来强化区域协调管理、利用区域内旅游资源特性实现旅游资源的联动、借助区域旅游市场的互动实现客源市场丰富的地区对湖南旅游市场的支撑、增加区域旅游合作的地域便捷性等对策。  相似文献   
132.
Abstract

Delayed neurotoxic ataxia, similar to that caused by neurotoxic organophosphorous compounds, has been shown to occur in hens after oral administration of Cyanofenphos (O‐ethyl‐O‐Cyanophenyl phenyl phosphonothionate) following either single or repeated oral doses. Axonal and myelin degeneration affecting the long tracts in spinal cord, peripheral nerves and medulla was demonstrated. The distal fibers with large diameters were particularly affected. This finding is a new contribution which has not been previously recorded. It implies that a thorough study of the structure‐activity relationships of phosphonothionates regarding their delayed neurotoxic effect is warranted.  相似文献   
133.
基于区域化过程的边缘地区发展模式——以南阳市为例   总被引:1,自引:0,他引:1  
边缘地区的发展问题一直是区域研究中的重点和难点,研究其发展轨迹、机理对于促进经济相对滞后的边缘区域发展具有重要意义。以豫鄂两省交界地区的南阳地区为例,在实地调研基础上,对其处于“核心→边缘”中的区域化过程进行阐述,采用区位商和“三轴图”产业重心方〖JP2〗法对其边缘化过程进行分析,针对南阳地区实际发展状况,提出未来解决边缘化的主要发展模式:(1)“CI”区域形象设计,推行区域形象发展模式;(2)“特色农产品+农户+中介+(市场)明星企业”的农业产业化模式、“特色资源+生态工业园”的工业发展模式;(3)以旅游和物流为主的交通驱动型第三产业发展模式,通过特色模式带动地区经济快速高效发展,以期为南阳地区及同类区域发展提供有益建议。  相似文献   
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本文对北京等华北中部5站1956至1985年旱涝成因进行了分析讨论.结果表明,区域性旱涝主要是在海洋和局地土壤热状况异常作用下产生的.对华北中部而言,冬季黑潮海温与局地地温变化是引起汛期旱涝变异最重要的原因.前期下垫面热源异常对后期旱涝影响往往是通过累积的异常加热造成环流形势和系统的异常而实现的.海温与地温影响降水的机制不同,前者的影响是大尺度的,而后者的影响只是区域性的.当海温异常造成的大尺度环流变化与局地热状况都有利于降水时.洪涝更容易发生,反之易旱.  相似文献   
136.
Mussoorie, a hill resort in the Garhwal Himalaya reveals the changing trends and impacts of tourist activity on its environment. This study was carried out during 1993–1994 and it showed that while Mussoorie had a permanent residential population of 25400 during the winter months, in the peak tourist season of May and June the population exceeded 200000 per month. Because of this huge influx of tourists the demand for lodges/hotels and other related infra-structure and super-structure facilities and amenities in the area was enormous, and it imposed a great stress on the natural environment.The data collected showed that from 1958 to 1988 the number of tourists had increased gradually but that from 1989 tourism in the town escalated following the political disturbances in the Kashmir Valley. The main purpose of the tourism was recreation (80%). It was recorded that the greatest number (60%) of the tourists were middle aged, 53% of the tourists worked in professional services. The majority of the tourists preferred to use the indigenous hotels and about 96% of the tourists used a private vehicle rather than public transport.The installation of modern tourist related facilities and infra-structure has led to the aesthetic degradation of the landscape. Tourist facility development is often disorderly and scattered. To reduce the traffic to Mussoorie town it is suggested that some nearby places like Dhanolti and Park estate should be developed for tourism.  相似文献   
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138.
• 90% total COD, 95.3% inert COD and 97.2% UV254 were removed. • High R2 values (over 95%) for all responses were obtained with CCD. • Operational cost was calculated to be 0.238 €/g CODremoved for total COD removal. • Fenton oxidation was highly-efficient method for inert COD removal. • BOD5/COD ratio of leachate concentrate raised from 0.04 to 0.4. The primary aim of this study is inert COD removal from leachate nanofiltration concentrate because of its high concentration of resistant organic pollutants. Within this framework, this study focuses on the treatability of leachate nanofiltration concentrate through Fenton oxidation and optimization of process parameters to reach the maximum pollutant removal by using response surface methodology (RSM). Initial pH, Fe2+ concentration, H2O2/Fe2+ molar ratio and oxidation time are selected as the independent variables, whereas total COD, color, inert COD and UV254 removal are selected as the responses. According to the ANOVA results, the R2 values of all responses are found to be over 95%. Under the optimum conditions determined by the model (pH: 3.99, Fe2+: 150 mmol/L, H2O2/Fe2+: 3.27 and oxidation time: 84.8 min), the maximum COD removal efficiency is determined as 91.4% by the model. The color, inert COD and UV254 removal efficiencies are determined to be 99.9%, 97.2% and 99.5%, respectively, by the model, whereas the total COD, color, inert COD and UV254 removal efficiencies are found respectively to be 90%, 96.5%, 95.3% and 97.2%, experimentally under the optimum operating conditions. The Fenton process improves the biodegradability of the leachate NF concentrate, increasing the BOD5/COD ratio from the value of 0.04 to the value of 0.4. The operational cost of the process is calculated to be 0.238 €/g CODremoved. The results indicate that the Fenton oxidation process is an efficient and economical technology in improvement of the biological degradability of leachate nanofiltration concentrate and in removal of resistant organic pollutants.  相似文献   
139.
Latin America comprehends notable variations in terms of natural environment, availability of natural resources, living standards, and demographic patterns. Latin America is a mosaic of cultures, post- and pre-Columbian. The rich variety of life forms discovered and described by chroniclers and traveling naturalists in the Neotropics contributed to the proposal, in mid-XVIIIth century, of a new system of classification and a scientific code of nomenclature for all organisms. Biodiversity was, for many centuries, a source of resources to be exploited in natura. In scientific circles, its inventory became the domain of taxonomists. But modern technology showed how important the miriad of life forms really are as sources of chemical molecules to be engineered as drugs and reassembled as novel manufactured products. We are on the brink of a new agricultural and medical revolution, thanks to the techniques of genetic engineering, which will lead eventually to the elimination of hunger and malnutrition.In this essay, the Brazilian environmental and social heterogeneity will serve as an example to illustrate some key points, which have influenced sustainability policies. The Amazon deforestation and indigenous knowledge (IK), subjects often associated with areas of high biodiversity, are usually the focus of environmental debates. The importance of IK in integrating development, reducing poverty and sustainability are considered together with the intellectual property rights of native populations.In the World Summit on Sustainable Development (WSSD) Implementation Plan, a few paragraphs were dedicated to Latin America, because of the pre-existing Action Platform on the Road to Johannesburg 2002, approved in Rio de Janeiro in October 2001. This paper calls attention to the need to draw up specific environmental policies for a region which shows an extremely high cultural and biological diversity, associated with a high availability of forests and water, among other resources.  相似文献   
140.
中央生态环境保护督察是党中央、国务院推进生态文明建设和生态环境保护工作的重大制度创新。《中央生态环境保护督察工作规定》于近期正式出台,首次以党内法规形式明确了生态环境保护督察的制度框架、程序规范、权限责任等。从发展历程来看,我国生态环境保护督察大致经历了督企为主、督政督企并举、党政同责三个阶段。生态环境保护督察具有突出政治站位、压实责任,坚持问题导向、强化震慑,突出边督边改、取信于民等基本特征。为强化成果应用,全面准确把握当前我国生态环境保护工作的重点难点,本文设置7个一级指标和18个二级指标对首轮中央生态环境保护督察所指问题的分布特征进行统计分析,初步剖析问题产生原因,并从督察对象、督察内容和督察体制方面对第二轮中央生态环境保护督察进行了展望。  相似文献   
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