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951.
Wioletta Rogula-Koz?owsk Barbara Kozielsk Grzegorz Majewski Patrycja Rogula-Kopie Walter Much Karolina Kociszewska 《环境科学学报(英文版)》2018,30(2):235-244
The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons(PAH) bound to submicrometer particles(particulate matter, PM_1) suspended in the air of university teaching rooms and in the atmospheric air outside. Two teaching rooms were selected in two Polish cities, Gliwice, southern Poland,and Warsaw, central Poland, differing with regard to the ambient concentrations and major sources of PM and PAH. The variabilities of indoor and outdoor 24-hr concentrations of PM_1-bound PAH, the ratio(I/O) of the indoor to outdoor 24-hr concentrations of PM_1-bound PAH, probable sources of PAH and the level of the hazard from the mixture of the 16 PAH(ΣPAH) to humans at both sites were analyzed. In both Warsaw and Gliwice, the mean concentrations of PM_1-bound ΣPAH were slightly higher in the atmospheric air than in the rooms. The indoor and outdoor concentrations of individual PAH in Gliwice were correlated,in Warsaw – they were not. Most probably, the lack of the correlations in Warsaw was due to the existence of an unidentified indoor source of gaseous PAH enriching PM_1 in phenanthrene, fluorene, and pyrene. Although the ambient concentrations of PM_1-bound PAH were low compared to the ones observed earlier at both sites, they were much higher than in other urbanized European areas. However, because of low mass share of heavy PAH in ΣPAH, the various indicators of the health hazard from the 16 PAH mixture were low compared to other regions. 相似文献
952.
通过实验模拟巷道生产作业环境,分析了矿井生产环境下光照衰减的机理,研究了普通LED灯、金卤灯、荧光灯、头戴LED矿灯4种灯具在不同环境参数下的透射性,得出其在不同矿井因素(粉尘浓度、风速、相对湿度)下光的透过性影响规律,结果表明:在矿井中风速和相对湿度的增加均能降低光的透过率,相对湿度变化对光的透过率影响较大,且风速和相对湿度的增加对粉尘浓度有一定的积聚作用。研究结果为井下照明灯具的合理选用提供了依据。 相似文献
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为了在水资源与水环境双重制约下制订人水和谐发展的政策提供决策支持,以我国中原经济区这一重点开发区域为例,基于层次分析法构建了以水系统自然条件、水系统服务功能及人类活动影响三要素(共计20项指标)为基础的流域水系统健康评价体系,并以2011年作为评价年,将中原经济区的水资源二级区作为基本流域单元对水系统健康状况进行评价. 结果表明:中原经济区9个水资源二级区中,除了淮河上游水资源二级区(3.20分,完全健康状态为5.00分)为基本健康状态、汉江水资源二级区(2.77分)和三门峡至花园口水资源二级区(2.18分)为亚健康状态以外,其余水资源二级区(0.55~1.77分)均为不健康及极不健康状态. 分析显示,人类活动影响是影响中原经济区内各流域水系统健康状况的主要原因,人口众多、工农业开发活动强度大使得其对水资源需求巨大. 部分水资源二级区对地下水资源依赖程度较高,造成不同程度的地下水超采现象. 伴随着高强度水资源利用的是水污染物的高强度排放,部分河流水污染状况严重,甚至在局部地区造成了地下水污染. 这种不健康的状态在中原经济区内由南向北随着水系统自然条件和水系统服务功能的降低呈加重趋势. 相似文献
957.
以核桃壳为原料,利用溶剂热法制备了磁性炭微球(MCMs),结合表面印迹技术制备了基于MCMs的磁性炭微球表面分子印迹材料(MMIPs).通过FT-IR、TGA、VSM和TEM等表征手段对其理化性能进行了表征,结果表明MMIPs为球形,印迹聚合层厚度50~80 nm,具有热稳定性和磁稳定性.采用吸附实验研究了MMIPs对AMP的识别与选择性吸附性能.Langmuir等温模型能较好地描述MMIPs对AMP的吸附平衡数据,25℃时MMIPs的单分子层最大吸附容量为40.96 mg·g-1.准二级动力学模型能较好的描述MMIPs对AMP吸附动力学行为.选择性分析结果表明,MMIPs对AMP具有较好地选择识别性,并且MMIPs可以循环使用5次.结合高效液相色谱分析技术,MMIPs已成功应用于牛奶样品中痕量AMP的分离、富集和回收,AMP的回收率为92.78%. 相似文献
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959.
The interaction of man and nature is considered in terms of classical ecology, which is becoming a synthetic systemic science based on a set of other sciences. The divisions of modern human ecology that deal with different organizational levels of ecological systems have been developed to different degrees. Attention is given to the necessity of discrediting the mechanistic concept of opposition between man and nature and taking into account the specific ecological functions of man related to group adaptation (culture), as well as the global role of all living organisms in the maintenance of environmental conditions on Earth. 相似文献
960.
O.C. Lind B. Salbu L. Skipperud K. Janssens J. Jaroszewicz W. De Nolf 《Journal of environmental radioactivity》2009
A combination of synchrotron radiation based X-ray microscopic techniques (μ-XRF, μ-XANES, μ-XRD) applied on single depleted uranium (DU) particles and semi-bulk leaching experiments has been employed to link the potential bioavailability of DU particles to site-specific particle characteristics. The oxidation states and crystallographic forms of U in DU particles have been determined for individual particles isolated from selected samples collected at different sites in Kosovo and Kuwait that were contaminated by DU ammunition during the 1999 Balkan conflict and the 1991 Gulf war. Furthermore, small soil or sand samples heavily contaminated with DU particles were subjected to simulated gastrointestinal fluid (0.16 M HCl) extractions. Characteristics of DU particles in Kosovo soils collected in 2000 and in Kuwait soils collected in 2002 varied significantly depending on the release scenario and to some extent on weathering conditions. Oxidized U (+6) was determined in large, fragile and bright yellow DU particles released during fire at a DU ammunition storage facility and crystalline phases such as schoepite (UO3·2.25H2O), dehydrated schoepite (UO3·0.75H2O) and metaschoepite (UO3·2.0H2O) were identified. As expected, these DU particles were rapidly dissolved in 0.16 M HCl (84 ± 3% extracted after 2 h) indicating a high degree of potential mobility and bioavailability. In contrast, the 2 h extraction of samples contaminated with DU particles originating either from corrosion of unspent DU penetrators or from impacted DU ammunition appeared to be much slower (20–30%) as uranium was less oxidized (+4 to +6). Crystalline phases such as UO2, UC and metallic U or U–Ti alloy were determined in impacted DU particles from Kosovo and Kuwait, while the UO2,34 phase, only determined in particles from Kosovo, could reflect a more corrosive environment. Although the results are based on a limited number of DU particles, they indicate that the structure and extractability of DU particles released from similar sources (metallic U penetrators) will depend on the release scenarios (fire, impact) and to some extent environmental conditions. However, most of the DU particles (73–96%) in all investigated samples were dissolved in 0.16 M HCl after one week indicating that a majority of the DU material is bioaccessible. 相似文献