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171.
Environmental exposure and health risk upon engineered nanomaterials are increasingly concerned. The family of mesoporous carbon nanomaterials(MCNs) is a rising star in nanotechnology for multidisciplinary research with versatile applications in electronics,energy and gas storage, and biomedicine. Meanwhile, there is mounting concern on their environmental health risks due to the growing production and usage of MCNs. The lung is the primary site for particle invasion under environmental exposure to nanomaterials. Here, we studied the comprehensive toxicological profile of MCNs in the lung under the scenario of moderate environmental exposure. It was found that at a low concentration of 10 μg/mL MCNs induced biophysical inhibition of natural pulmonary surfactant. Moreover, MCNs at similar concentrations reduced viability of J774 A.1 macrophages and lung epithelial A549 cells.Incubating with nature pulmonary surfactant effectively reduced the cytotoxicity of MCNs.Regarding the pro-inflammatory responses, MCNs activated macrophages in vitro, and stimulated lung inflammation in mice after inhalation exposure, associated with lung fibrosis.Moreover, we found that the size of MCNs played a significant role in regulating cytotoxicity and pro-inflammatory potential of this nanomaterial. In general, larger MCNs induced more pronounced cytotoxic and pro-inflammatory effects than their smaller counterparts. Our results provided valuable information on the toxicological profile and environmental health risks of MCNs, and suggested that fine-tuning the size of MCNs could be a practical precautionary design strategy to increase safety and biocompatibility of this nanomaterial.  相似文献   
172.
阐述了GHS产生的背景及其在减少化学品事故,提高化学品安全管理水平,消除贸易壁垒,降低监管、企业成本等方面发挥的重要作用。介绍了GHS国内应用情况,对国内推行GHS提出了几点建议。  相似文献   
173.
以四川省蓬安县为例,基于GIS空间分析技术,结合蓬安当地实际,选取水源涵养、土壤保持能力和生物多样性进行生态敏感性评价,获得蓬安县区域敏感性现状图,并以此为基础构建生态安全格局,该格局注重区域的内在机理与周围的相对联系,保证各生态环境功能区成为具有各自特点、功能和生命活力而又彼此联系的有机体,为其生态文明建设过程中重点领域和重点工程设计规划提供基础支撑,阐明了生态敏感性评价在生态文明建设中的运用,为县级生态文明建设规划做出了贡献.  相似文献   
174.
文章从评价主体、评价对象、介入时间、评价内容、公众参与、技术方法、政策制度等方面构建了包括"评价人员素质、早期介入、指标体系、评价标准、公众参与方式、工作程序完整性、法律法规、替代方案"等19项评价指标,提出了AHP-模糊综合评价法对规划环境影响评价有效性进行综合评价的方法,并以南阳石化专业园区规划环境影响评价为实证案例进行了定量分析.  相似文献   
175.
以兰州市公共交通(分为公交车和出租车两种)为研究对象,运用生态足迹法,测算2010年-2014年兰州市客运交通生态足迹,并计算兰州市公共交通的生态效率和生态足迹强度.结果表明:公共交通生态足迹年均占比为7.41%;公共交通生态足迹和客运量呈同步增长态势,公共交通生态足迹年均增长1.71%;在影响公共交通生态足迹的因素中,公交车和出租车的化石能源足迹年均占比分别为76.06%和62.32%;就生态效率而言,公交车生态效率是出租车生态效率的6.24倍.  相似文献   
176.
生态环境保护目标指标是环境保护和生态建设规划中的核心内容,制定科学合理的规划指标体系,能够确保规划各项重点任务顺利实施.通过回顾分析"十一五"、"十二五"环境保护和生态建设规划指标体系,结合广西环境现状和发展趋势,在与国家和广西同期规划、计划、方案等衔接基础上,研究提出广西"十三五"环境保护和生态建设规划指标体系,设置了环境质量改善、总量控制、污染治理、风险防范、生态保护和生态公共服务等6个方面共29个指标,以期更好地指导"十三五"环境保护和生态建设工作.  相似文献   
177.
The purpose of this study was to validate the use of adenosine triphosphate (ATP) for evaluating hygiene intervention effectiveness in reducing viral dissemination in an office environment. The bacterial virus MS-2 was used to evaluate two scenarios, one where the hand of an individual was contaminated and another where a fomite was contaminated. MS-2 was selected as a model because its shape and size are similar to many human pathogenic viruses. Two separate experiments were conducted, one in which the entrance door push plate was inoculated and the other in which the hand of one selected employee was inoculated. In both scenarios, 54 selected surfaces in the office were tested to assess the dissemination of the virus within the office. Associated surface contamination was also measured employing an ATP meter. More than half of the tested hands and surfaces in the office were contaminated with MS-2 within 4 h. Next, an intervention was conducted, and each scenario was repeated. Half of the participating employees were provided hand sanitizer, facial tissues, and disinfecting wipes, and were instructed in their use. A significant (p < 0.05) reduction was observed in the number of surfaces contaminated with virus. This reduction in viral spread was evident from the results of both viral culture and the surface ATP measurements, although there was no direct correlation between ATP measurements with respect to viral concentration. Although ATP does not measure viruses, these results demonstrate that ATP measurements could be useful for evaluating the effectiveness of hygiene interventions aimed at preventing viral spread in the workplace.  相似文献   
178.
目前气象观测业务和空气污染分析中存在对霾日统计的分歧,甚至出现空气污染日无霾的现象,对霾观测标准的科学划分,显得非常重要和紧迫。利用2013—2015年廊坊市气象观测站能见度、相对湿度、霾人工观测资料和廊坊市环保局AQI、PM25浓度等气象环保资料,对目前观测业务和空气污染分析中常用的三种霾观测、统计方法进行了对比分析。分析发现:目前廊坊气象观测站所依据的记录霾天气现象的标准,与实际大气污染相趋甚远,不能反映实际的空气污染状况,建议国家及省级相关部门及早根据实际情况,更新霾观测标准,更好地为当前大气污染的防治工作提供客观依据。  相似文献   
179.
王梦勤  郭长仕 《环境工程》2013,(Z1):390-392
国内大量石灰石-石膏湿法烟气脱硫装置需进行增容改造,介绍了增容改造的主要方案及各方案的应用案例,分析了方案选择的影响因素,总结了增容改造的主要特点,提出了改造项目的建议,为火电机组的脱硫增容改造提供借鉴。  相似文献   
180.
Polyvinyl alcohol is a refractory compound widely used in industry. Here we report supercritical water oxidation of polyvinyl alcohol solution and desizing wastewater with and without sodium hydroxide addition. However, it is difficult to implement complete degradation of organics even though polyvinyl alcohol can readily crack under supercritical water treatment. Sodium hydroxide had a significant catalytic effect during the supercritical water oxidation of polyvinyl alcohol. It appears that the OH ion participated in the C-C bond cleavage of polyvinyl alcohol molecules, the CO2-capture reaction and the neutralization of intermediate organic acids, promoting the overall reactions moving in the forward direction. Acetaldehyde was a typical intermediate product during reaction. For supercritical water oxidation of desizing wastewater, a high destruction rate (98.25%) based on total organic carbon was achieved. In addition, cases where initial wastewater was alkaline were favorable for supercritical water oxidation treatment, but salt precipitation and blockage issues arising during the process need to be taken into account seriously.  相似文献   
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