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971.
Sapountzaki K 《Disasters》2005,29(2):195-212
This paper attempts to contribute to international discourse on the responsibility of macro structures (economic and political) and private agencies for the production and distribution of vulnerability. It does so by focusing on an individual economic entity, small manufacturing firms (SMFs), in a specific location, western Athens, Greece. By evaluating the losses that SMFs sustained in the earthquake of 7 September 1999, the paper points to variations in vulnerability levels among such firms and highlights the 'sources' of vulnerability they confront. Furthermore, the SMF recovery cycle is systematically monitored in parallel with relevant public policies and state reactions to private recovery methods. The analysis illustrates processes that externalise recovery costs, alter the relationship between physical and socio-economic vulnerability and shift the vulnerability load from macro structures to individual agencies or vice versa. It is based on two methodological approaches: the division of vulnerability into three constituent components (exposure, resistance and resilience); and the conceptual split between producers and carriers of vulnerability.  相似文献   
972.
In this study, fluorine concentrations in drinking water and in urine of residents from a fluorine exposure area in China were tested. DMFT (average number of decayed, missing and filled teeth) of local residents in four age groups were also determined. The results of the study indicate that in fluorine exposure areas, there is a strictly positive correlation between fluorine content in urine and the fluorine content in drinking water. Effect of dental caries by high fluorine content drinking water is different for the different age groups. High fluorine content drinking water is more dangerous for 15-and 18-year-old groups than 5- and 12-year-old groups.  相似文献   
973.
The short term human exposure studies conducted on populations exposed to high concentrations of inorganic arsenic in soil have been inconsistent in demonstrating a relationship between environmental concentrations and exposure measures. In Australia there are many areas with very high arsenic concentrations in residential soil most typically associated with gold mining activities in rural areas. This study aimed to investigate the relationship between environmental arsenic and urinary inorganic arsenic concentrations in a population living in a gold mining area (soil arsenic concentrations between 9 and 9900 mg kg(-1)), and a control population with low arsenic levels in soil (between 1 and 80 mg kg(-1)). Risk factors for increased urinary arsenic concentrations were also explored. There was a weak but significant relationship between soil arsenic concentrations and inorganic urinary arsenic concentration with a Spearman correlation coefficient of 0.39. When participants with greater than 100 mg kg(-1) arsenic in residential soil were selected, the coefficient increased to 0.64. The geometric mean urinary inorganic arsenic concentration for the exposed group was 1.64 microg L(-1) (相似文献   
974.
The gamma radiation in samples of a variety of natural tiling rocks (granites) imported in Cyprus for use in the building industry was measured, employing high-resolution gamma-ray spectroscopy. The rock samples were pulverised, sealed in 1-l plastic Marinelli beakers, and measured in the laboratory with an accumulating time between 10 and 14 h each. From the measured gamma-ray spectra, activity concentrations were determined for (232)Th (range from 1 to 906 Bq kg(-1)), (238)U (from 1 to 588 Bq kg(-1)) and (40)K (from 50 to 1606 Bq kg(-1)). The total absorbed dose rates in air calculated from the concentrations of the three radionuclides ranged from 7 to 1209 nGy h(-1) for full utilization of the materials, from 4 to 605 nGy h(-1) for half utilization and from 2 to 302 nGy h(-1) for one quarter utilization. The total effective dose rates per person indoors were determined to be between 0.02 and 2.97 mSv y(-1) for half utilization of the materials. Applying dose criteria recently recommended by the EU for superficial materials, 25 of the samples meet the exemption dose limit of 0.3 mSv y(-1), two of them meet the upper dose limit of 1 mSv y(-1) and only one clearly exceeds this limit.  相似文献   
975.
PROBLEM: This study involved a quasi-induced exposure analysis of 4 years of crashes involving older drivers in the state of Kentucky. METHOD: Single- and multivehicle crashes were disaggregated according to the number of passengers: (a) no passenger, (b) one passenger, and (c) two or more passengers. RESULTS: Overall, the presence of two or more passengers was found to negatively impact the probability that drivers 75 years of age or older were at fault in crashes. Several potential factors were studied for interactive effects with passengers: vehicle occupant gender mix, time of the day, road curvature, grade, and number of lanes. The negative impact of passengers increased for some geometric road conditions. However, older drivers were found to be safer at night when carrying two or more passengers. The presence or absence of passengers was not found to affect the 65- to 74-year-old driver group. Groups of male vehicle occupants with a 75+ male driver were found to have high single-vehicle crash rates. IMPACT: These results are among the first to directly consider the effect of passengers on the crash-causing propensity of older drivers and the findings suggest more work is warranted to consider causes for the crash rate differences.  相似文献   
976.
Nitrogen and phosphorus cycling in a eutrophic Louisiana freshwater lake system (Lac des Allemands) was studied. Nutrients from runoff entering the lake, as well as sediment-interstitial and lake water nitrogen and phosphorus fractions, were measured seasonally. Sedimentation rates in the lake were determined using137Cs dating.Phosphorus levels in the lake were found to be largely dependent on concentrations in the incoming bayou water from upland drainage. Lake water concentrations appear to respond to fluctuations in incoming waters. Laboratory equilibrium studies showed bottom sediments in the lake are a major sink for the incoming dissolved orthophosphate phosphorus. Total nitrogen concentrations in the lake water generally exceeded incoming runoff concentrations, suggesting fixation by the large blue-green algae population in the lake as being the major source of nitrogen to the system.Sedimentation ranged from 0.44 cm/year to 0.81 cm/year, depending on the proximity to the inlet bayous. Even though the lake is eutrophic the sediment served as a buffer by removing large amounts of carbon, nitrogen, and phosphorus through sedimentation processes. Carbon, nitrogen, and phosphorus were accumulating in the sediment at rates of 60, 7.1, and 1.1 g/m2/year, respectively.The water quality of the lake is likely to continue to decline unless measures are taken to reduce municipal, industrial, and agricultural inputs of phosphorus into the lake.  相似文献   
977.
通过四种不同的方法制备了生物防护复合面料,通过基本性能测试选取了最优方案。将以聚四氟乙稀复合膜为中间层的复合面料进行了综合性能测试,将其制成连体式防护服,并对防护服的整体性能进行了测试。结果表明:该复合面料具有优良的生物防护性和透湿性,防护服结构合理。  相似文献   
978.
Sixteen polycyclic aromatic hydrocarbons (PAHs) were determined in 24 duplicate-diet samples from people in Taiyuan during summer and winter in 2009. Dietary intake of PAHs for 2862 participants was subsequently estimated by a survey in Taiyuan. Results from these 24 samples were compared with a raw food study in Taiyuan in 2008. Three main sources of dietary PAHs are vegetables, wheat flour and fruits, the sum of which contributes 75.95% of PAHs in dietary food. Compared to the estimated value in raw food, much more B[a]Peq (benzo[a]pyrene equivalents) were detected in food samples collected in the duplicate-diet study in Taiyuan (60.75 ng/day). The cooking process may introduce more B[a]Peq into food, and the relative contribution of 16 PAHs in the diet would be changed during the cooking procedure.  相似文献   
979.
齐丽  任玥  刘爱民  黄业茹  赵震  王江  李泓 《环境科学》2017,38(4):1317-1326
2014年4月至2015年1月对北京市某生活垃圾焚烧发电厂周边6 km范围内7个采样点采集环境空气,应用高分辨气相色谱-高分辨质谱(HRGC-HRMS)联用技术对二英(PCDD/Fs)浓度水平进行监测并对其组成特征及时空特征进行了分析.结果表明该生活垃圾焚烧发电厂周边环境空气中PCDD/Fs质量浓度的变化范围为8.9~140 pg·m-3,毒性当量(TEQ)变化范围为0.11~1.8 pg·m-3,其中秋季霾天4个采样点和冬季全部采样点超出日本环境空气质量标准限值(TEQ:0.6 pg·m-3).1,2,3,4,6,7,8-HpCDF和OCDD是四季空气中PCDD/Fs质量浓度的主要贡献单体,年平均贡献率分别为20.5%和14.0%,而2,3,4,7,8-PeCDF是总TEQ贡献最大的单体,年平均贡献率为43.3%.空间分布特征表现为各采样点浓度水平与距污染源距离远近没有显著相关性;季节变化特征表现为冬季值显著高于其他季节,分析可能与冬季燃煤采暖及大气扩散条件差导致的大气颗粒物污染较重有关,与各季采样时段内大气PM10和PM2.5的平均浓度水平呈正相关相一致.样品中二英同族体及异构体分布指纹谱图与该焚烧设施排放烟气存在差别,主成分分析(PCA)源解析结论与指纹谱图特征分析结论一致.二英呼吸暴露剂量估算结果表明该区域人群呼吸暴露风险总体处于较为安全的水平[0.060~0.224 pg·(kg·d)-1],但仍需关注大气颗粒物重污染天气发生时的呼吸暴露风险.  相似文献   
980.
目的研究电镀黑铬的耐候性,对汽车行业的黑铬应用风险进行评估。方法通过对比分析的方法,以传统电镀亮铬性能为参照,从耐腐蚀、耐氙灯老化、自然暴晒三个方面介绍汽车用装饰性电镀黑铬的耐候性,并对黑铬耐候性不良的原因进行分析、讨论。结果电镀黑铬的耐自然暴晒性能、耐腐蚀性能均较传统亮铬差,镀层自钝化效果差镀层氧化是影响镀层耐候性的主要因素。结论电镀黑铬不适合应用于汽车外饰零部件。  相似文献   
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