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1.
KH Kim DX Ho CG Park CJ Ma SK Pandey SC Lee HJ Jeong SH Lee 《Environmental engineering science》2012,29(9):875-889
To investigate the environmental behavior of volatile organic compounds (VOCs) in urban areas, their concentrations were measured at four urban monitoring sites (namely, N, S, E, and W) in Seoul, Korea (February to December 2009). A total of 27 compounds were quantified that consist of four chemical groups: aromatic (AR), halogenated aromatic, halogenated paraffin, and halogenated olefin. Results were evaluated by focusing on these four functional groups just mentioned and their summation term as total VOC (TVOC) along with several individual species (mainly AR species, that is, benzene, toluene, ethylbenzene, and xylene). The highest concentration of chemical groups was found from AR (71.1±42.1?ppbC), while that for individual species confirmed the dominance of toluene (7.48±3.88?ppb). The analysis of spatial distribution indicated that high TVOC levels were recorded at sites N and W, while it was not so significant such as S and E in terms of TVOC budget. Seasonal variation of these VOCs was characterized by the peak values in December to reflect the combined effects of pronounced source activities and meteorological conditions. Analysis of spatial variations in VOC levels between the four urban sites indicated that their distributions are tightly affected by local source processes in each area. 相似文献
2.
本文利用电磁波观测台的实测资料,对宁蒗Ms5.1级、会泽Ms4.4级地震前电磁波异常信号特征、干扰排除、异常判别进行研究,分析了震前电磁波信号图象和异常时空特征,得出电磁波主信号异常出现在主震前20天左右的结论。 相似文献
3.
On 11 August 1985, a large inadvertent release occurred from a chemical manufacturing plant in Institute, West Virginia. The emission was related to overheating of a storage tank that contained chemicals for the production of aldicarb, a cholinesterase inhibiting pesticide. As a result of this emission, 136 persons were treated in five local emergency rooms, 29 of whom were hospitalized for one or more days, mostly for observation. No fatalities resulted. Interviews with treated persons and non-treated community residents confirmed that the health effects were transient and compatible with exposure to irritating vapors rather than with exposure to methyl isocyanate (a chemical used in the process) or to aldicarb. Only 5% of the treated persons and 5% of the community residents surveyed were adequately warned of the emission by the plant siren. Because persons in the nearby community are potentially vulnerable to chemical injury, we recommend the development of an improved warning system, a formal evacuation procedure, and other measures to limit exposure of persons in this area in the event of a future release. 相似文献
4.
低温胁迫对番茄光合特性及抗氧化酶活性的影响 总被引:6,自引:0,他引:6
根据番茄对低温的反应,于2010年10月-2011年3月间,设计了人工控制试验系统以研究低温胁迫(5℃,7℃,9℃,11℃)对设施番茄光合色素含量、最大光合速率、叶绿素荧光参数、抗氧化酶活性的影响,为设施番茄低温致灾气象指标的确定提供依据。结果表明:不同低温胁迫下叶绿素a,Chla/Chlb和最大光合速率均存在不同程度的降低,而叶绿素b和类胡萝卜素含量则有所升高。低温5℃处理3 d和7℃处理4 d后番茄最大光合速率均为负值,经过25℃恢复5 d后仍无显著升高;低温9℃、11℃胁迫下番茄最大光合速率随处理天数的增加而降低,且经过5 d的恢复处理后最大光合速率可以基本恢复至正常水平。叶绿素荧光参数分析表明,低温胁迫降低了PSII的原始光能转换效率和潜在活性,番茄的Fv/Fm,qP,ETR均显著降低,且随胁迫温度和胁迫时间的不同,Fv/Fm,qP,ETR的变化程度有所不同。不同低温胁迫使得番茄SOD,POD,CAT,MDA酶的活性均有不同程度升高,且温度越低,处理时间越长,升高幅度越大。因此,低温5℃处理3 d或者低温7℃处理4 d是番茄发生严重冷害的临界指标,该研究结果可为作物低温灾害防御及气象灾害预警提供参考。 相似文献
5.
朱金义 《防灾减灾工程学报》2013,(5):44-48
为了达到降低发电厂NOx排放物、改善生态环境的目的,针对采用DDR旋流燃烧器产生NOx较高的问题,马莲台发电厂在脱硝改造工程中大胆采用新型低氮燃烧器与SCR烟气脱硝相结合的技术,取得了良好效果。结果表明:燃烧器改造后锅炉运行各项指标正常,锅炉效率略有提高,NOx排放浓度明显减少,由原来的679.85 mg/Nm3降为290 mg/Nm3,取得了巨大的社会效益和经济效益。 相似文献
6.
为了达到宁夏地区要求现役330 MW级别火电机组NOx排放值100 mg/Nm3以下和改善环境的目的,青铜峡铝业发电有限责任公司对1号锅炉的燃烧器进行技术改造。结果表明:改造后锅炉在330 MW负荷下NOx排放平均值为240 mg/Nm3,比改造前降低45%;锅炉效率达到93.39%(高于设计值0.01%)、飞灰含碳量2.98%(低于设计值0.02%)、过热器减温水量和再热器减温水量均小于设计值;有效解决了锅炉改造前的结焦和超温现象。 相似文献
7.
This paper examines the dependability of the Event Assessment Tool over time. The latter is part of a CD-ROM--Emergency Risk Communication CDCynergy--distributed primarily to public information officers in the United States by the Centers for Disease Control and Prevention. The Event Assessment Tool is designed to aid emergency professionals in identifying the magnitude of a crisis event and to suggest appropriate actions to confront such a situation. Applied twice during the 2001 anthrax bioterrorism crisis in Boca Raton, Florida, the tool functioned in a binary manner by first indicating a moderate crisis level (on 4 October) and then four days later (on 8 October) a highly intense crisis, suggesting that it is time sensitive. This anthrax event provides an opportunity for crisis and disaster managers to understand the dynamic nature of crises. Rapid changes during these types of events suggest that any metric used to predict intensity must account for this variability. Additional limitations and implications of the tool are discussed. 相似文献
8.
为探索进一步提高循环流化床(circulating fluidized bed,CFB)锅炉脱硫效率,在一台燃用混矸煤(洗中煤 60%和煤矸石 40%)的 300 MW 循环流化床锅炉的尾部烟道上,设计了简易煤灰增湿活化脱硫工艺装置,研究其机理及影响因素。试验结果表明:煤灰增湿脱硫反应很迅速,增湿 Ca/S 摩尔比、水钙摩尔比和出口温距是影响其增湿脱硫效率的主要因素。煤灰增湿活化脱硫工艺提高了脱硫剂的利用率,降低了 SO2 排放浓度和脱硫运行成本;控制了粉煤灰中游离氧化钙的含量,提高了粉煤灰的综合利用率。 相似文献
9.
华北中北部地面运动衰减研究 总被引:5,自引:0,他引:5
使用河北省数字地震遥测台网25个台的259条波形记录资料,采用三段几何衰减模型,通过反演得到华北中北部地区剪切波的衰减模型和介质的品质固子Q(f)值,Q(f)=420.8f~(0.384)。研究发现,华北中北部地区的Q值与广东地区很接近,而与其它地区差异较大。 相似文献
10.
基于河南省109个气象站1971-2010年夏季(6-8月)逐日最高气温和平均气温资料,采用气候统计学分析方法,分析了近40年河南省夏季≥35℃、≥38℃和≥40℃高温日数的时空特征及可能的变化趋势.结果表明:1971-2010年河南省夏季3个等级高温日数在空间上呈现出豫西北高海拔和豫东南低海拔地区较多,其它地区较少的分布特征,高值中心位于豫西地区的偃师附近,在时间上无显著的线性变化趋势,但是在年代间呈现出“多-少-多”的变化特征,最近10年夏季高温日数最多;从各台站趋势变化的空间分布看,豫西北海拔较高地区台站呈增加趋势的较多,豫东和豫西南台站呈减少趋势的较多.夏季平均气温和≥35 ℃(r =0.58,n=4360)、≥38℃(r=0.39,n=4360)以及≥40℃(r=0.27,n=4360)高温日数均呈显著正相关.在全球气候变暖背景下,未来河南省高温日数将可能进一步增加,特别是≥35℃的高温日数. 相似文献
11.
The severe floods of 1987 in Bangladesh had devastating effects on many development activities. Here, the use and condition of improved sanitation facilities (double pit water sealed latrines) during the 1987 peak flood period are presented. Two surveys on the use and condition of the latrines were carried out in May (pre-flood) and September (post-flood) 1987 in a rural area 60 km north of Dhaka, with a population of about 4500. General usage of the latrines by the population aged five years or more decreased from 88% to 78% ( p < 0.001) after the flood. Only 40% of the 343 latrines which were in use and had no damaged component at the time of the pre-flood survey still had no damaged components after the floods. Fencing was the component which suffered the most damage. It was the only component which was installed and maintained by the users, project staff being responsible for all other components. The estimated post-flood repair cost was approximately US $4.0 per latrine. Development of an affordable and durable fencing is recommended. 相似文献
12.
《Environmental Hazards》2013,12(2):121-138
In Bangladesh, drought is seasonal and can destroy crops, causing hardship to poor agricultural labourers and others who cannot find alternative sources of income. Droughts most commonly affect the northwestern region, which generally has less rainfall than the rest of the country. In this context, this study attempts to measure the existing level of drought resilience with indicators related to Socio-economic, Institutional and Physical (SIP) conditions in two of the most drought-prone districts, namely Rajshahi and Chapai-Nawabganj. The results of 14 sub-districts (upazilas) show a variation of 2.41 (lowest resilience) and 3.61 (highest resilience) in a scale of 1–5. Some of the critical areas that need improvement include education and awareness, conflict resolution on water usage, policy enhancement, coordination among different stakeholders and proper land-use pattern. SIP methodology can be used as a rapid planning tool at the district level, and as a micro-level planning and improvement tool at the sub-district level. The tool has potential application for a participatory and process-based approach of engaging local stakeholders in minimizing drought risks in future. 相似文献
13.
江苏省典型年梅雨洪涝灾害对比分析 总被引:1,自引:0,他引:1
梅雨期降水形成的洪涝和枯梅年产生的干旱是江苏省主要的气象灾害.为了能客观地划分各年梅雨的旱涝等级,从而为防灾减灾决策提供依据,利用江苏省近50年来的梅雨资料,考虑梅期持时长短、梅期平均日雨量及暴雨日数等3个因子,给出了梅雨强度计算模型及梅期旱涝指标,较好地反映了江苏省每年各地的梅期旱涝状况.结合实际灾情,确定了典型梅雨洪涝年的标准.针对1954,1991和2003年3个比较典型的梅雨洪涝年,进行了详细的比较分析,结果表明:(1)长江及淮河流域上游的客水、入梅之前的降水量和梅期降水会直接影响该省梅雨期的洪涝灾情;(2)1991年的洪涝是历年来最为严重的,1954年的洪涝稍重于2003年;(3)3个典型梅雨洪涝年中全省最涝的地区都位于沿淮地区或江淮之间地区的北部,淮北地区这3年中都出现了较重的涝灾,淮北南部的灾情重于北部. 相似文献
14.
Post-disaster reconstruction (PDR) poses specific and complex challenges that government agencies have to deal with. Existing crisis management and communication models as well as literature on social media adoption by public organisations tend to focus on the critical stage, neglecting the issues that arise when the social, physical and cultural environments affected by a disaster have to be rebuilt. Conversely, this paper presents some preliminary findings on the Government to Citizen (G2C) communications and social media usage in PDR settings. The PDR process that followed the earthquakes in Emilia-Romagna (Northern Italy) in 2012 was used as a case study. Data derived from field notes and multiple-choice questionnaires revealed that government agencies provided information mainly about housing and infrastructure and financing and that they addressed this information to all citizens, although information was sometimes targeted specifically to business people, homeowners and members of community-based groups. Government officers gave preference to face-to-face contacts, Web portals and printed material. Social media were used predominantly as additional means of communication of PDR-related information, thus underrating their potential for community engagement and G2C bidirectional communication. In the discussions, findings are integrated into and validated against literature and communication theories. 相似文献
15.
声发射技术在桥梁结构健康监测中的应用研究进展 总被引:1,自引:0,他引:1
声发射技术作为一种被动的、动态的监测手段,在工程和材料领域得到了广泛的应用,正日益受到桥梁结构健康监测研究者的关注。本文回顾了近年来国内外基于声发射技术的桥梁结构健康监测研究状况。首先,简要介绍了声发射的基本原理和声发射信号处理方法;其次,详细分析了声发射技术在桥梁结构健康监测中的研究成果,包括钢筋混凝土桥、钢结构桥、桥梁结构关键构件和无线声发射传感器及其网络等;最后,分析了声发射技术在桥梁结构健康监测领域应用中存在的一些问题,并对声发射技术的应用前景进行了探讨。 相似文献
16.
汤逊湖水体叶绿素浓度遥感估测研究 总被引:5,自引:0,他引:5
内陆水体叶绿素浓度遥感监测的各种经验模型在模型的方法和参数上都有一定的时空限制。为了实现武汉汤逊湖叶绿素浓度的遥感监测,利用同步实测的光谱数据和水质数据进行了该湖泊叶绿素浓度的遥感定量反演研究。首先分析了汤逊湖水体的反射率光谱曲线;其次通过相关分析的方法,发现了汤逊湖水体反射率在单波段法、一阶微分法和比值法建模中的最优波段或组合,并进行了一元线性建模;最后对3种模型的反演精度进行了比较分析。结果表明,对于汤逊湖叶绿素浓度遥感反演,一阶微分法和比值法优于单波段法,一阶微分法的最优波段在446.9 nm附近,比值法的最优波段组合为R861.1/R865.7,二者回归R2都在0.86以上。本项研究可为汤逊湖叶绿素浓度的遥感估测提供了参考。 相似文献
17.
Siri Thoresen Arnfinn Tønnessen Camilla Vibe Lindgaard Anne Lie Andreassen Lars Weisæth 《Disasters》2009,33(3):353-368
Adequate responses to disasters and emergency situations rely, among other factors, on coping abilities in disaster workers and emergency personnel. In this study, different aspects of disaster-related stressors and training/experience were investigated in Norwegian personnel (n = 581) mobilised for the 2004 tsunami disaster. The level of stress reactions, measured nine to ten months after the tsunami, was relatively low in this sample, indicating that the personnel coped well with the challenges of the disaster. The level of intrusive memories was higher in disaster-area personnel (n = 335) than in home-base personnel (n = 246). Stress reactions were significantly associated with witnessing experiences (disaster-area group) and with having to reject victims in need of help (both groups). Specific preparation for the mission was associated with a lower level of stress reactions in disaster-area personnel. Such factors may be considered in training and preparation programmes for disaster workers. 相似文献
18.
基于遥感参数特征空间的福建省干旱监测 总被引:1,自引:0,他引:1
归一化植被指数(NDVI)和地表温度(LST)是描述地表特征的两个重要参数,通过新型的MODIS卫星数据反演得到NDVI和LST,采用基于NDVI-IST特征空间的条件植被温度指数(VTCI)模型,对2001-2002年福建省发生的严重秋冬春连续干旱灾害进行了监测验证,并利用气象观测数据对VTCI模型临测结果进行了分析.研究结果表明:VTCI模型能够真实地反映地表水分供应状况,能较好地反映区域旱情分布和旱情发展过程,VTCI值越小表示干旱灾害越严重.当旬的VTCI平均值与前一旬的降水量有着较高的相关性,利用VTCI模型能够近实时进行干旱监测,具有较高的业务化应用前景. 相似文献
19.
Managing volunteers: FEMA's Urban Search and Rescue programme and interactions with unaffiliated responders in disaster response 总被引:1,自引:0,他引:1
In the aftermath of disasters it is not uncommon for a large number of individuals, ranging from professional technical responders to untrained, albeit well meaning, volunteers, to converge on site of a disaster in order to offer to help victims or other responders. Because volunteers can be both a help and a hindrance in disaster response, they pose a paradox to professional responders at the scene. Through focus group interviews and in-depth structured interviews, this paper presents an extended example of how Urban Search and Rescue (US&R) task forces, a type of professional technical-responder organisation, interact with and utilise volunteers. Findings show that US&R task forces evaluate the volunteers in terms of their presumed legitimacy, utility, and potential liability or danger posed during the disaster response. Other responses to volunteers such as a feeling of powerlessness or the use of volunteers in non-technical ways are also explored. This paper demonstrates some key aspects of the relationship between volunteers and formal response organisations in disasters. 相似文献
20.
Dellinger B D'Alessio A D'Anna A Ciajolo A Gullett B Henry H Keener M Lighty J Lomnicki S Lucas D Oberdörster G Pitea D Suk W Sarofim A Smith KR Stoeger T Tolbert P Wyzga R Zimmermann R 《Environmental engineering science》2008,25(8):1107-1114
The 10th International Congress on Combustion Byproducts and their Health Effects was held in Ischia, Italy, from June 17-20, 2007. It is sponsored by the US NIEHS, NSF, Coalition for Responsible Waste Incineration (CRWI), and Electric Power Research Institute (EPRI). The congress focused on: the origin, characterization, and health impacts of combustion-generated fine and ultrafine particles; emissions of mercury and dioxins, and the development/application of novel analytical/diagnostic tools. The consensus of the discussion was that particle-associated organics, metals, and persistent free radicals (PFRs) produced by combustion sources are the likely source of the observed health impacts of airborne PM rather than simple physical irritation of the particles. Ultrafine particle-induced oxidative stress is a likely progenitor of the observed health impacts, but important biological and chemical details and possible catalytic cycles remain unresolved. Other key conclusions were: (1) In urban settings, 70% of airborne fine particles are a result of combustion emissions and 50% are due to primary emissions from combustion sources, (2) In addition to soot, combustion produces one, possibly two, classes of nanoparticles with mean diameters of?~10?nm and?~1?nm. (3) The most common metrics used to describe particle toxicity, viz. surface area, sulfate concentration, total carbon, and organic carbon, cannot fully explain observed health impacts, (4) Metals contained in combustion-generated ultrafine and fine particles mediate formation of toxic air pollutants such as PCDD/F and PFRs. (5) The combination of metal-containing nanoparticles, organic carbon compounds, and PFRs can lead to a cycle generating oxidative stress in exposed organisms. 相似文献