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1.
市政排污空间作为城市公共基础设施的重要组成部分,易积聚可燃气体形成爆炸性环境。结合排污空间的特殊环境条件,采用Fluidyn-MP多物理场数值模拟软件,建立了20 L球形爆炸罐分析模型,通过改变初始温度和初始压力,对排污空间甲烷-空气混合物爆燃特性及其变化规律进行模拟研究。结果表明:初始温度升高导致甲烷-空气混合物最大爆炸压力降低,缩短了到达最大爆炸压力的时间;初始压力增加导致最大爆炸压力急剧升高,并延长了到达最大爆炸压力的时间;最大爆炸压力对初始压力的敏感程度远大于初始温度的影响。此外,随着初始温度和初始压力的升高,爆炸火焰平均传播速度增加,而火焰传播速度对初始温度较敏感。  相似文献   
2.
Achieving coexistence between large carnivores and humans in human-dominated landscapes (HDLs) is a key challenge for societies globally. This challenge cannot be adequately met with the current sectoral approaches to HDL governance and an academic community largely dominated by disciplinary sectors. Academia (universities and other research institutions and organizations) should take a more active role in embracing societal challenges around conservation of large carnivores in HDLs by facilitating cross-sectoral cooperation to mainstream coexistence of humans and large carnivores. Drawing on lessons from populated regions of Europe, Asia, and South America with substantial densities of large carnivores, we suggest academia should better embrace the principles and methods of sustainability sciences and create institutional spaces for the implementation of transdisciplinary curricula and projects; reflect on research approaches (i.e., disciplinary, interdisciplinary, or transdisciplinary) they apply and how their outcomes could aid leveraging institutional transformations for mainstreaming; and engage with various institutions and stakeholder groups to create novel institutional structures that can respond to multiple challenges of HDL management and human–large carnivore coexistence. Success in mainstreaming this coexistence in HDL will rest on the ability to think and act cooperatively. Such a conservation achievement, if realized, stands to have far-reaching benefits for people and biodiversity.  相似文献   
3.
Waste accumulation is a grave concern and becoming a transboundary challenge for environment. During Covid-19 pandemic, diverse type of waste were collected due to different practices employed in order to fight back the transmission rate of the virus. Covid-19 was proved to be capricious catastrophe of this 20th century and even not completely eradicated from the world. The havoc created by this imperceptible quick witted, pleomorphic deadly virus can't be ignored. Though a number of vaccines have been developed by the scientists but there is a fear of getting this virus again in our life. Medical studies prove that immunity drinks will help to reduce its reoccurrences. Coconut water is widely used among all drinks available globally. Its massive consumption created an incalculable pile of green coconut shells around the different corners of the world. This practice generating enormous problem of space acquisition for the environment. Both the environment and public health will benefit from an evaluation of quantity of coconut waste that is being thrown and its potential to generate value added products. With this context, present article has been planned to study different aspects like, coconut waste generation, its biological properties and environmental hazards associated with its accumulation. Additionally, this review illustrates, green technologies for production of different value added products from coconut waste.  相似文献   
4.
三峡库区水土流失特点及其环境危害防治措施探讨   总被引:15,自引:0,他引:15  
水土流失是三峡库区主要环境问题之一,也是库区产生大量泥沙的根本因素,更是造成库区人民生活贫困的根源。本文就三峡库区水土流失的特点及其环境危害作了分析,提出了相应的防治措施,为水土流失防治工程提供科学依据。  相似文献   
5.
湖北省2008年初低温雨雪冰冻过程气候特征分析   总被引:3,自引:0,他引:3  
2008年初,湖北省出现了严重的低温雨雪冰冻灾害,直接经济损失高达110亿元以上,有必要对灾害期间的气候特征进行系统、科学的分析和总结。对湖北省76个气象站2008年1月12日~2月3日气温、降水(雪)、日照以及低温持续日数等要素进行时空间差异分析及历史与同期比较,并选取10个代表站历史上所有低温雨雪天气过程,对其过程持续低温日数、最长连续雨雪日数、过程极端低温进行比较分析。结果表明:(1)此次过程的平均气温异常偏低,该省大部为-1~-2℃,比常年同期偏低4~6℃,为各站历史同期最低,其中主要是最高气温异常偏低所致,但极端低温并不低;(2)降雪过程频繁,雨雪量异常偏多;(3)低温冰冻持续时间长,该省大部在16~22 d,位于历史第一;(4)日照异常偏少。持续而稳定的大气环流异常形势是湖北省大范围低温雨雪天气的直接原因。  相似文献   
6.
生态文明建设对环境法理论变革的影响   总被引:1,自引:0,他引:1  
随着人类社会由工业文明向生态文明的转变,环境法理论也随之发生着变革。近年来。众多学者对环境法理论的变革问题进行了热烈的讨论。生态文明的法律观。承认自然界及其生物具有内在价值。主张人与自然的和谐发展。为生态文明建设提供了坚实的法学理论支持。  相似文献   
7.
阐述了开展工业区群环境影响评价的意义,比较了单个工业园区和工业区群环评的异同,以广州番禺区工业区群环评项目为例,简述了该环评的主要内容和特点,并提出了建议。  相似文献   
8.
Cultural heritage is being addressed by a number of charters and conventions and it is clear that its consideration within decision-making processes is progressively becoming a real challenge, both for developers and public authorities. Against this background, this paper reviews the environmental assessment framework developed by the European Community, as this should increasingly influence decision making about cultural heritage in an urban setting. The legislative framework for access to environmental information is also reviewed because of its relevance to the decision-making process.The Directives on Environmental Impact Assessment and Strategic Environmental Assessment both require a consideration of cultural heritage in decision making. This requirement can go some way to addressing the paradox in the European Community's position whereby the community wishes to conserve and enhance its own cultural identity whilst, at the same time, cultural heritage is usually defined at a local level. The present paper suggests that, given their flexibility, the two European Community directives on environmental assessment constitute a promising opportunity to address this seeming paradox, but that there is a significant gap between legal obligations and the methodological tools to meet them.  相似文献   
9.
In recent years flows of foreign direct investment (FDI) to developing countries have rapidly been increasing. It is now an important contributor to the national economy and urban growth in scores of developing countries. Rapid urbanization in these countries is leading to many problems in the cities. Existing urban infrastructure and municipal services have been unable to cope with the increased demand arising from growing population and rapid economic growth. Consequently, the environment in these cities has deteriorated alarmingly. This paper assesses the role of FDI in urban environmental management (UEM) by analyzing the linkages between them for Hanoi City in Vietnam. The paper's analysis and findings are presented under three main themes: one, FDI, employment and income; two, FDI and environmental degradation; and three, potential of utilizing FDI for the provision of urban environmental infrastructure and services (UEI&S) in order to improve the urban environment. Both primary and secondary source data have been used. Policy implications of the research findings are drawn from the perspective of sustainable development.  相似文献   
10.
Observations of air temperature changes in a steppe marmot burrow were performed from late July to mid-October. Until early September, temperature in the burrow remained relatively constant, but then it began to decrease rapidly. This occurred after air temperature above the ground became equal to the temperature in the burrow. Supposedly, it is in this particular period that marmots begin to plug the entrance to the burrow with earth, thus reducing heat exchange between the increasingly cold aboveground air and the air in the burrow.  相似文献   
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