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321.
为了解郑州市不同行业企业挥发性有机物(VOCs)污染特征及潜在危害,通过Summa罐和气袋采集样品,之后采用GC-MS/FID对样品进行测定分析.结果表明:郑州市包装印刷企业排放VOCs组分主要为含氧VOCs(OVOCs),包括乙酸乙酯和异丙醇,占比93.1%以上;汽车制造、家具制造和涂料生产企业VOCs组分主要为芳香烃,占比为33.5%~90.0%,以间/对-二甲苯、邻-二甲苯和乙苯为主;食品加工企业VOCs中卤代烃占比较高,为52.3%;橡胶企业VOCs主要为卤代烃和烷烃,占比分别为25.5%和28.8%;石墨碳素企业VOCs主要为芳香烃和OVOCs,占比分别为28.5%和24.1%.对比以往研究发现,郑州市与其他城市溶剂使用企业VOCs排放特征较为类似,但由于生产工艺及原辅料使用不同,相同行业企业中不同环节VOCs组分存在差异.风险评估结果显示,各企业排放的VOCs组分对臭氧生成潜势(OFP)和危害指数(HI)贡献具有一定正关联性,尤其苯、甲苯、乙苯及二甲苯等C_6~C_8芳香烃对OFP和HI贡献较大.汽车制造企业3号和家具企业5号HI值分别为1.18和2.74,均高于EPA规定限值,主要与该企业生产过程中使用溶剂型原辅料有关,且排放的主要以芳香烃为主,尤其苯、甲苯、乙苯、二甲苯和三甲基苯等C_6~C_9苯系物对HI和OFP的贡献较高,今后需重点管控溶剂型企业VOCs的排放. 相似文献
322.
John D. Bullough Andrew Bierman 《International journal of occupational safety and ergonomics》2019,25(2):311-320
Purpose. New light sources including light-emitting diodes (LEDs) have elicited questions about retinal damage, including the blue-light hazard. Some organizations have recommended avoiding using LEDs with correlated color temperatures exceeding 3000?K, since they tend to produce greater short-wavelength energy. This article provides quantitative comparisons among light sources and use cases as they affect the blue-light hazard. Methods. The spectral radiant power characteristics of incandescent, fluorescent, LED and daylight sources were evaluated in terms of blue-light hazard using standard procedures for phakic, aphakic and pseudophakic eyes. Results. Under most use cases, LEDs do not exhibit greater risk for the blue-light hazard than other sources (e.g., incandescent). Because they generally produce little to no ultraviolet energy, LEDs often present less risk to aphakic eyes. Conclusions. LEDs present no special concerns for the blue-light hazard over some other common sources in typical use cases because photophobic responses limit exposure to bright sources. Where photophobic responses might not occur (e.g., eye surgery patients or premature infants) or where individuals suppress these responses (e.g., stage actors), caution is necessary. Evidence remains inconsistent regarding the risk of human retinal damage from long-term exposures to light insufficient to reach acute blue-light hazard thresholds. 相似文献
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324.
为提升企业的安全风险管控水平,以R化工厂的甲醇成品罐区为例,运用系统的危险源辨识方法对其设备、工艺过程、切罐、倒罐操作程序、生产作业活动等进行系统全面的危险源辨识,形成安全风险信息数据库。基于安全风险信息数据库,开发各种风险管控工具。利用信息化技术,构建安全风险管控信息系统,对企业实行动态化的安全管理。 相似文献
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327.
天然气管道时常受到破坏,并诱发巨大的射流火焰,可能引燃周围建构物体。系统地分析了管道压力对天然气射流火热辐射灾害的影响,以建立天然气射流火热辐射灾害的系统定量分析方法。基于压力管道小孔泄漏模型和权重-多点源热辐射计算模型,建立了目标物体最大入射热辐射通量、管道压力和目标物与泄漏小孔水平距离的定量关系式。进而选定10 k W/m~2和31.5 k W/m~2作为城镇建筑物遭受引燃和机械破坏的热辐射通量阈值,得到了不同管道压力下天然气射流火热辐射灾害范围。计算结果表明,GB 50028—2006《城镇燃气设计规范》依据管道压力所规定的燃气管道与建筑物的安全间距不能完全满足天然气管道破坏时射流火焰的安全要求,与某武汉天然气管道射流火事故后果一致。 相似文献
328.
SANTTU KAREKSELA ATTE MOILANEN SEPPO TUOMINEN JANNE S. KOTIAHO 《Conservation biology》2013,27(6):1294-1303
Globally expanding human land use sets constantly increasing pressure for maintenance of biological diversity and functioning ecosystems. To fight the decline of biological diversity, conservation science has broken ground with methods such as the operational model of systematic conservation planning (SCP), which focuses on design and on‐the‐ground implementation of conservation areas. The most commonly used method in SCP is reserve selection that focuses on the spatial design of reserve networks and their expansion. We expanded these methods by introducing another form of spatial allocation of conservation effort relevant for land‐use zoning at the landscape scale that avoids negative ecological effects of human land use outside protected areas. We call our method inverse spatial conservation prioritization. It can be used to identify areas suitable for economic development while simultaneously limiting total ecological and environmental effects of that development at the landscape level by identifying areas with highest economic but lowest ecological value. Our method is not based on a priori targets, and as such it is applicable to cases where the effects of land use on, for example, individual species or ecosystem types are relatively small and would not lead to violation of regional or national conservation targets. We applied our method to land‐use allocation to peat mining. Our method identified a combination of profitable production areas that provides the needed area for peat production while retaining most of the landscape‐level ecological value of the ecosystem. The results of this inverse spatial conservation prioritization are being used in land‐use zoning in the province of Central Finland. 相似文献
329.
People spend most of their time indoors, where air pollution levels rival and often exceed those outdoors for a number of important pollutants. Yet, little is known about people’s knowledge of indoor environmental hazards. The purpose of the current study was to construct a measure of indoor environmental knowledge. A set of 78 true/false items were developed with input from a panel of experts. The set of items was truncated with traditional item analyses, resulting in a reliable set of 21 items (α = .79). Concurrent validity was established by a significant correlation between the indoor environmental knowledge (IEK) scale and an established measure of science literacy (r = 0.44, p < .001). Schema theory guided the assumption that the two measures should be related. Convergent validity was established by the significant regression of science literacy, formal education in science and math, and status as an engineering student on IEK scale score, accounting for 25% of the variance in the IEK scale score. Future research avenues are proposed and limitations are discussed. 相似文献
330.
Aging coastal defences around the UK are challenging managers to redesign schemes to be resilient to extreme events and climate change, be cost-effective, and have minimal or beneficial environmental impact. To enable effective design, reduced uncertainty in the assessment of flood risk due to natural variability within the coastal forcing is required to focus on conditions that pose highest threat. The typical UK standard of protection for coastal defences is to withstand a 0.5% annual probability event, historically also known as a 1 in 200 year return period event. However, joint wave-water level probability curves provide a range of conditions that meet this criterion. We examine the Dungeness and Romney Marsh coastal zone, a region of high value in terms of habitat and energy assets, to quantify the uncertainty in flood depth and extent generated by a 0.5% probability event, and to explore which combinations of wave and water levels generate the greatest threat. 相似文献