粉末活性炭处理酚类突发性水污染的应用研究

以苯酚和多种氯酚(CPs)为代表的酚类是一类重要的有机污染物。针对饮用水突发性酚类污染物控制,考察了粉末活性炭(PAC)吸附工艺对苯酚及CPs的去除效果,并讨论了主要影响因素。结果表明,对CPs和苯酚的吸附反应可在10~60 min、300 min内完成,吸附速率从快到慢依次为TCP、MCP、DCP、PCP和苯酚。由于酚羟基(Ar—OH)电离作用受到影响,在3~11范围内去除率随pH值升高而降低。少量腐殖酸对吸附影响不大,但TOC质量浓度超过10 mg/L时腐殖酸可产生明显竞争吸附作用。热力学拟合表明,吸附反应符合Freundlich和Langmuir吸附等温式,苯酚/CPs在PAC上的吸附过程以物理吸附为主,且为放热反应,较低温度有利于吸附反应的进行。相比于准一级反应和孔内扩散反应,准二级动力学方程可较好地描述吸附过程。将PAC用于中山市某饮用水源的模拟突发性污染应急处理,投加10 mg/L的PAC即可有效去除原水中超过饮用水标准3~5倍的CPs类污染物,同时水处理成本仅有少量增加。     

危险化学品大气污染事故模拟

近年来国内突发性危险化学品大气污染事故频繁发生,为及时做出风险评估及救援决策,需要在事故初发阶段快速模拟确定其危害程度和范围。以东部沿海地区某一假想化工厂突发性泄漏事故为例,对其可能的危害范围进行模拟,采用WRF-CALMET模式模拟事故区域的高分辨率气象场,耦合随机模式模拟污染物的扩散过程。结果表明,WRF能精确地模拟1 km分辨率的近地面气象场的演变趋势。将该结果用于CALMET模式获得了高分辨率风场数据,再输入随机模式中进行扩散模拟,结果显示该模式能合理地模拟出污染物的危害范围及地面最高浓度。     

Understanding the context of alcohol impaired driving for fatal crash–involved drivers: A descriptive case analysis

Objective: The objective of this study was to understand the social context and circumstances surrounding alcohol-impaired driving prior to fatal crash involvement for drivers with an illegal blood alcohol concentration (BAC ≥ 0.05 g/100 ml or 0.00 g/100 ml for restricted license holders).

Methods: Coroners' case reports investigating fatal crashes in South Australia over a 3-year period (2008–2010) were examined. The personal and crash characteristics of drivers with an illegal BAC were compared with those who had a legal BAC. For each driver with an illegal BAC, information was recorded including characteristics of last trip, location and social context of alcohol consumption, quantity and type of alcohol consumed, BAC level, presence of drugs, perceived alcohol intoxication, and alcohol dependence. Official traffic offense records were also obtained.

Results: Of the 284 fatal crashes included in the study, 34% (n = 95) involved a driver or rider with an illegal BAC. Prior to the crash, alcohol was most frequently consumed by drivers in rural areas, within private homes, and was part of normal social activities. Drivers recorded a high level of alcohol impairment, with a mean BAC of 0.173 g/100 ml and a level of alcohol dependence that was above the Australian national average (7.4 vs. 3.9%). In addition, 23% of drivers were known to be experiencing psychological stress at the time of the crash. The results also confirm that drink driving recidivism continues to be a significant problem, with 44% of drivers recording at least one prior alcohol driving offense.

Conclusions: Alcohol-impaired driving continues to be a leading cause of fatal crashes. The popularity of drinking at home, particularly in rural areas, has implications for police enforcement strategies and suggests that drink driving interventions that focus on community values and looking after friends might be beneficial. Importantly, the study highlights the need for a broader holistic approach to reduce the high levels of alcohol consumption and alcohol dependence underlying drink driving behavior.     

Working conditions and sleepiness while driving among truck drivers

Objective: The objective of this study is to identify the role of working conditions as predictors of sleepiness while driving among truck drivers.

Methods: This was a cross-sectional study carried out among truck drivers who transported grains to Paranaguá Port, Paraná, Brazil. The truck drivers were interviewed and completed a self-administered questionnaire to collect data on sociodemographic and behavioral variables, working conditions, consumption of illicit psychoactive substances, and sleep patterns. Drivers were considered to be sleepy while driving if they reported a medium or high probability of napping while driving at night, during the daytime, or while stopped in traffic. The statistical analysis used logistic regression models progressively adjusted for age, behavioral variables, sleep duration, and other working conditions.

Results: In total, 670 male drivers, with a mean age of 41.9 (±11.1) years, were enrolled. The prevalence of sleepiness while driving was 31.5%. After model adjustments, the following working conditions were associated with sleepiness while driving: Distance from the last shipment of more than 1,000?km (odds ratio [OR]?=?1.54; 95% confidence interval [CI], 1.07–2.23) and a formal labor contract with a productivity-based salary (OR = 2.65; 95% CI, 1.86–3.78). Consumption of illicit psychoactive substances (OR = 1.99; 95% CI, 1.14–3.47) was also associated with sleepiness while driving.

Conclusions: Distance traveled and a formal labor contract with productivity-based earnings were the working conditions associated with sleepiness while driving, regardless of other working or behavioral characteristics, age, consumption of illicit psychoactive substances, and sleep duration.     

论生产安全事故救援费用的承担机制

为了实现重大生产安全事故救援费用的公平负担,保障救援机制的可持续性,通过规范分析和比较分析,探讨了在第三方队伍参与救援的情况下,重大生产安全事故救援费用的承担原则和实现机制。研究结果表明:第三方队伍参与事故救援所产生的当次费用原则上必须由事故责任单位承担,但在其拖欠费用或者暂时缺乏支付能力的情况下,应当由承担应急救援职责的事发地政府先行垫付;由此在事发地政府和事故责任单位之间产生的是公法之债,可以通过行政强制执行的方式加以追偿。     

基于GM(1,1) Markov的危化品道路运输事故与交通事故预测及关系研究

为准确预测我国危化品道路运输及交通2类事故数量趋势,探究其内在联系,在单一的灰色GM（1,1）模型基础上与马尔科夫过程组合形成灰色GM（1,1）—马尔科夫预测模型,以2013—2017年2类事故数量的原始序列探讨了该组合预测模型的实际应用,采取平均相对误差、均方差比值、小误差概率对模型进行精度检验。研究结果表明:在组合预测模型较优情况的研究中,2类事故数量历年来波动性相似,因危险化学品自身的性质、包装和装卸使得2类事故量变化频率存在偏差;2018—2019年的危化品道路运输事故分别为485起和480起,交通事故分别为225 294起和234 454起。     

埋地输氢管道泄漏爆炸事故后果模拟分析

为了输氢管道的安全建设与运营,基于计算流体力学FLACS软件,模拟了埋地输氢管道在半受限空间内的泄漏爆炸事故后果,探讨了泄漏孔径、泄漏时长、输氢压力和环境风速对爆炸事故后果的影响规律,并得出相应的危险区域。结果表明:泄漏孔径、输氢压力和最大爆炸超压均与危险区域呈正相关关系,泄漏时长对事故后果几乎无影响;随着输氢压力的增大,危险区域受建筑物和风速的影响更为明显,在建筑物附近形成了狭长的危险区域带;最大爆炸超压和危险区域随环境风速的增大均呈现出先增大后减小的趋势。     

城镇油气管道事故应急疏散决策优化

为实现油气管道事故中城镇大规模应急疏散的智慧决策,构建基于改进的自适应蚁群算法的应急疏散路径优化模型,开发基于油气管道典型事故后果分析的城镇大规模应急疏散决策优化系统平台(LSSED)。LSSED在地理信息系统平台上,针对油气管道泄漏引起的扩散、喷射火、池火、BLEVE、蒸气云爆炸等典型事故进行事故后果分析,对疏散通道当量长度和疏散时间成本函数进行定量评价,实现大规模应急疏散方案的智慧决策和避难方案的全局优化。案例分析表明,LSSED平台实现了基于地理信息系统的典型事故时变环境信息和应急疏散路径优化算法的数据传递及系统集成,实现了基于事故后果分析的城镇大规模人群疏散路径和避难方案优化,可为城镇安全规划和应急管理提供参考和借鉴。     

基于STAMP模型的丰城坍塌事故原因分析

为了系统地分析建筑施工事故原因、有效预防同类事故,运用STAMP模型从控制角度详细分析了一起特别重大坍塌事故,分别从物理过程及环境因素、基层操作原因以及管理层原因3方面分析了导致事故的控制缺陷,并且根据分析结果,提出事故控制措施及建议。结果表明:STAMP模型不仅可以分析各个层级的原因,还可以找出层级之间以及层级内不同组织之间的交互影响原因;建设方、施工方、监理方以及承包方对项目管理内容交叉与重叠,且沟通与协调缺失是导致错误决策和不恰当控制动作产生的主要因素;基层不安全控制动作直接导致事故发生,但取决于管理因素,管理层的原因是预防同类事故的重点。     

丁二烯储罐泄漏事故定量风险评价

为了有效预防丁二烯引发的事故,基于定量风险评价的指标,以某企业丁二烯储罐为工程实例,采用重大危险源区域定量风险评价软件CASST-QRA,模拟丁二烯储罐泄露事故后果影响范围,定量评价其对周边环境所造成的风险大小和可接受程度。结果表明:某企业的丁二烯储罐个人风险和社会风险均可接受,模拟结果可为制订应急救援预案及安全防范措施提供参考;同时,研究成果可以对企业的安全管理和有关行政部门的安全监督提供指导与依据,也为其他丁二烯储罐的管理和运行提供借鉴。