江苏省沛县农业面源污染现状及对策

通过对江苏省沛县农业面源污染的现状进行全面的分析,指出现阶段县域经济转型发展过程中农村环境污染的主要来源及产生原因,并提出了相应的治理对策,对其他地区促进农业产业发展,改善农村环境质量,建设社会主义新农村都有一定借鉴作用。     

Impact of NOx Emissions Released from a Gas Turbine-Based Power Plant on the Ambient Air Quality

The number of gas turbine- (GT-) based power plants is rapidly increasing to meet the world’s power demands. Until a few years ago, fossil fuel, and specifically fuel oil, was considered the major energy source for gas turbine operation. Due to the high amount of pollution that fuel oil generates, natural gas has become a popular source of energy due to its lower emissions compared to fuel oil. As a result, many GTs have switched to natural gas as an alternative to fuel oil. However, pollutants expelled from GT-based power plants operating on natural gas impact surrounding air quality. The objective of this study was to examine the dispersion of nitrogen oxides (NO_x) emitted from a GT-based power plant located in the Sultanate of Oman. Supported by CALPUFF dispersion modeling software, six scenarios were investigated in this study. The first four scenarios considered a case where the GT-based power plant was operating on natural gas during winter and summer and for open and combined cycle modes. The remaining two scenarios considered, for both open and combined cycle modes, the case where the GT-based power plant was operating on fuel oil. Whether run by natural gas or fuel oil, CALPUFF simulation results for both seasons showed that NO_x concentrations were higher when GTs were used in the combined cycle mode. The concentrations were still lower than the allowable concentrations set by the United States Environmental Protection Agency (U.S. EPA) standards. In contrast, for the case where the power plant operated on fuel oil, the NO_x one-hour average simulated results exceeded the allowable limits only when the combined cycle mode was activated.     

微塑料污染的水生生态毒性与载体作用

近年来微塑料的水生生态环境污染与生态毒害问题引起了科学界的广泛关注。在总结国内外相关研究的基础上,本文对水生态环境中微塑料的来源、形成与分布展开分析;对微塑料污染的生态毒性研究进展给予评述;并深入探讨了微塑料在生态系统中扮演的多重载体角色。鉴于微塑料污染的严峻现实,我国应尽快开展有关微塑料环境污染和生态毒理方面的系统研究,并辅以政策引导和经济支持。     

非正式制度视角下的旅游小费研究

在总结国内外小费研究的基础上,运用社会学、心理学和经济学的相关知识,从非正式制度的角度研究旅游小费现象。认为小费作为一种非正式制度存在,有其历史性、合理性和有效性。现阶段我国旅游小费发展有一定困难,多数旅游者不认可小费,政策规定难以有效实行等。但是我国旅游小费的发展具有可行性,旅游小费能在一定程度上消除旅游业的不稳定因素,提高旅游从业者收入,提升旅游服务质量,促进旅游业的健康有序发展。同时认为培育旅游小费观念,提升旅游服务意识和水平,规范旅游市场环境等方面是促进旅游小费非正式制度在我国发展的必要途径。     

低碳经济下的秦皇岛休闲农业发展研究

秦皇岛市作为休闲度假旅游胜地,在实施＂旅游立市＂发展战略中把休闲农业作为一个新的经济增长点,在应对低碳时代的发展要求、发展休闲农业方面做出积极实践。通过分析低碳经济下发展休闲农业的必要性和秦皇岛休闲农业的发展现状,提出秦皇岛休闲农业发展的对策和路径选择。     

地方环境保护标准现状分析及“十二五”发展思路

我国地方环境保护标准工作起步晚、发展慢,仍与国家标准存在较大的差距。地方环境保护标准制(修)订的基本思路逐步由传统的保障总量削减目标实现、加严污染排放控制,向改善环境质量、保障环境安全以及实现区域联防联控并重转变。以北京、上海、广东等主要省市地方标准现状为例,分析了地方标准的工作难点,并探讨了"十二五"时期地方标准发展的思路。     

环保型钻井液的研究应用现状及发展趋势

介绍与分析了现阶段国内外环保型钻井液及其处理剂的特点和研究现状。推荐了钻井液体系环保指标及毒性的评价方法。指出制约中国环保型钻井液技术开发的因素,对环保型钻井液技术研究的重点和发展趋势进行了分析。指出环保型钻井液的发展趋势,强调无毒性硅酸盐钻井液是今后研究的重点。     

江西柘林水库集水区近50年气候干湿状况研究

柘林水库的面积和库容较大,但集水区面积相对较小,水资源亏缺是其主要制约因子,研究近50 a来水库集水区的气候干湿状况和变化趋势,对于水库的运行调度、效益发挥以及制定科学的投资计划具有很好的参考价值。基于江西柘林水库集水区内3个常规气象站1958～2007年的逐日降水、气温等要素观测资料,计算不同时间尺度的标准化降水指数（SPI指数）,以衡量集水区干湿情况;用FAO Penman Monteith 方法计算参考蒸散量;以年降水量与年参考蒸散量的差值近似代表最大径流深度。采用线性趋势拟合、滑动平均等分析方法,对水库集水区的旱涝、参考蒸散量、最大径流深度等的时间分布状况、季节变化、变化趋势等进行了分析。研究结果表明：（1）柘林水库集水区1998年以来年降水量呈明显下降趋势,而年参考蒸散量呈上升趋势,导致年最大径流深度下降明显,水库水资源不足;（2）近50 a柘林水库集水区的降水集中度呈增加趋势,强降水对总降水量的贡献增大,旱涝发生风险均增加;（3）近50 a柘林水库集水区旱涝互现、旱重于涝     

Numerical modelling for effect of water curtain in mitigating toxic gas release

Hydrogen fluoride and ammonia are widely used in chemical industries. Both substances are hazardous and frequently a source of leakage accidents. Since a hydrogen fluoride release accident occurred in Gumi, S. Korea (2012), the Korea Occupational Safety and Health Agency (KOSHA) has emphasized that special attention and management are needed with respect to toxic substances. For post-release mitigation, a water curtain is known as one of the most effective and economical systems. In this study, a computational fluid dynamics (CFD) program was used to identify the effect of using a water curtain as a mitigation system for toxic substances that leak out from industrial facilities. Simulations were conducted to analyze how effectively a water curtain could mitigate the dispersion of toxic substances. To verify the simulation's accuracy, the INERIS Ammonia dispersion experiment and Goldfish experiment were simulated and compared. Various water curtains were applied to the simulated field experiment to confirm the mitigation factors with toxic substances. The results show that the simulations and experiments are consistent and that the dispersion of toxic substances can be mitigated by water curtains in certain circumstances.     

影响华宁县环境空气现状指标分析及改善对策建议

本文根据2017-2019年华宁县环境空气自动站监测数据,分析影响华宁县在玉溪市环境空气质量排名中靠后的主要指标,分析三年来影响排名主要指标的PM10、PM2.5的现状以及产生的原因,提出改善华宁县环境空气现状的对策建议。