非点源污染影响分析及防治措施

与点源污染相比,非点源污染具有分散性和隐蔽性、随机性和不确定性、广泛性和不易监测性等特点,已成为水环境保护工作面临的主要障碍,在全球得到共同关注。针对非点源污染影响展开分析。详细论述了非点源污染的类型、来源及危害,提出了控制非点源污染的防治措施。     

循环冷却水系统静电离子棒抑垢除垢实验研究

介绍了离子棒静电水处理器的抑垢、除垢机理,在电厂循环冷却水系统模拟试验台上通过空白试验、加载试验、挂片试验对该装置的抑垢、阻垢性能进行了测试和研究,试验结果表明,该设备具有较好的抑垢、阻垢作用,能有效提高循环冷却水的浓缩倍率。     

API standard 521 guidance on mixing of hot/cold liquids and prevention of superheat limit explosions

American Petroleum Institute (API) standards and recommended practices have identified inadvertent mixing of hot and cold liquids as a potential cause for equipment overpressure since 1955. The limited guidance has been informative but provides minimal if any details on conditions that could cause an overpressure and its potential severity. Therefore, the user must interpret how and when to prevent and/or mitigate the scenario. This guidance has changed little over the years. In June 2020, API published the 7th Edition of API Standard 521 which now provides specific guidance as to conditions whereby pressure relief devices can be considered for protection and conditions where prevention remains as the only recourse. This paper discusses the basis for the revised guidance in API Standard 521 and includes supplemental guidance.     

Soccer,concussions, and safety: Perceptions of parents of youth soccer participants

Introduction: The rate of concussions in youth soccer is among the highest of all youth sports. Parents play an important role in caring for their children and making decisions regarding whether they should participate in a sport, such as soccer, where concussions are well known. This study examined parental perceptions regarding: (a) coaches’ role in concussion management, (b) heading restriction policies, and (c) overall concussion risk and participation issues. Method: Online surveys were completed by 419 parents of youth soccer players who participated in the largest U.S. youth soccer programs nationwide. Results: Findings indicated 44.5% of the respondents had considered keeping their children from playing organized soccer and 47.2% were concerned about a potential decline in youth soccer participation due to concussions. Nearly 69% of responding parents agreed that heading should be banned for participants 10 years old or younger, while 56.5% thought heading should not be limited for participants 13 or older. Only 35% of parents were very confident about their child’s coach’s ability to properly identify concussions and remove those suspected of a concussion from play. Parents’ socioeconomic status (SES), soccer coaching and playing experience, and previous history of concussion(s) were key predictors of greater perceived risk about concussions. Conclusions: Findings from this study shed light on parents’ perceptions about concussions and related safety issues in youth soccer. Understanding what parents believe about concussions is vital to preserve youth soccer participation and can be used to strengthen education and policies that promote a safer environment for youth sport participants. Practical Applications: Youth soccer coaches can benefit from stronger, comprehensive educational efforts at the league/club level. Additionally, parents of youth athletes who are in the lower SES communities should be targeted to receive concussion safety information and/or interventions that would improve their knowledge, attitude, and practices regarding concussion safety.     

基于“纵深防御”原则的危化企业事故预防系统建立

危险化学品生产是当前的高危行业和安全管理的重点领域。面对事故频发的严峻形势,如何开展好危险化学品生产企业的安全管理,建立事故预防系统防止事故的发生非常关键。“纵深防御”原则作为核电厂实现核安全的一项基本原则,为核电厂长期稳定安全的发展奠定了坚实的基础,对危化企业提升事故预防能力,建立事故预防系统有较强的借鉴意义。借鉴“纵深防御”原则,文章分析危化企业应用“纵深防御”原则预防和减少事故发生的必要性,结合生产特点建立了事故纵深防御系统,对企业提高安全管理水平,预防事故的发生有重要的意义。     

基于量子化学分析表面活性剂对不同煤种润湿机理的影响*

为研究不同类型表面活性剂对煤润湿性的调控机理,首先将所选煤样的润湿性与煤样成分进行关联分析,然后采用透过高度法实验及量子化学计算相结合的方法研究表面活性剂对煤样润湿性的影响效果及机理。结果表明:煤的润湿性与煤中固有水分、灰分呈正相关关系,与煤中固定碳呈负相关关系;所选取的4种表面活性剂的加入会降低褐煤的亲水性,而对长焰煤、焦煤和无烟煤亲水性有提升作用,并且十二烷基硫酸钠对于这3种煤样亲水性的提升作用最为明显;表面活性剂分子、水分子及煤分子的表面静电势分布共同决定了表面活性剂对煤浸润性的影响。     

Graduated driver licensing: review of evaluation results since 2002

Unintentional injury from motor-vehicle crashes is the number one cause of death among teenagers in the United States. Increasingly, jurisdictions have adopted three-stage graduated driver licensing (GDL) systems for young novice drivers. Since a previous review of U.S. GDL evaluation results, many more U.S. states and Canadian provinces have implemented GDL and/or had enough time pass that additional evaluation results are now available. Twenty-one studies of GDL within 14 individual jurisdictions, and six studies of GDL in the U.S. nationwide, were collected, reviewed, and summarized. Positive results (usually crash reductions) of varying degrees were reported from nearly all the studies. Given differences in approaches, study goals, methods, and analyses, the results are surprisingly consistent. Overall, GDL programs have reduced the youngest drivers' crash risk by roughly 20 to 40%. Research on teen driving and comprehensive GDL enhancements could further reduce teen drivers' motor-vehicle crashes, injuries, and fatalities. IMPACT ON INDUSTRY: Policy-makers, as well as the motor vehicle, insurance, and other industries have been involved in teen driving safety and could enhance and coordinate their roles.     

基于人误系统复合状态(MSHES)的人误防范理论研究

评析国内外以第一代人因可靠性分析(静态)、第二代人因可靠性分析(动态)为主体形成的人误防范理论和方法;针对目前不能量化人的生理、认知、心理等相关非结构性和非确定性参数和数据的"瓶颈",建立基于人-机-环系统业务流程的人误系统复合状态(Multiplex State ofHumanErrors System,MSHES)结构模型;探求运用粗糙集数据挖掘,对资深专业人员的经验规则信息、人因事故或事件分析的信息,挖掘人因层次结构中的根因与人误层次结构中的差错之间的关联关系,构建基于规则的人误防范专家系统结构模型;探究人的风险性评估和人误防范理论。     

从“人”与“机”关系看机械企业事故的预防

首先,分析"以机器为本"和"以人为本"的两种设计思想,指出设计过程的各个阶段都要高度重视"以人为本"并对该理念加以应用;其次,通过大量的文献资料查阅和对多家机械企业的实地事故情况调查,总结出多家机械企业几年来发生的24项事故,23项不良设计和11项良好设计,从工业设计专业以及人机工程学角度对其进行了过程总结、基本原因分析,提出"以机器为本"的设计思想是许多工业产品设计不良的根本原因,而工业产品设计不良或者工作环境设计不佳则导致多种事故的发生,因此,"以人为本"的设计思想必须深入到产品设计的全过程中,以创造出无危险的安全技术保障;最后,笔者再次强调,企业的安全生产和事故控制,必须坚持"以人为本"的基本策略和理论,同时呼吁社会各界要对"以人为本"的设计思想充分理解并加以应用,共创安全的和谐社会。     

信息整合在城市综合防灾减灾中的应用

城市防灾减灾信息化建设中,"信息孤岛"问题造成信息资源的浪费,严重影响了灾害管理的效率和效果。笔者提出信息整合的思路——以信息共享和满足个性化需求为整合目标,按照标准化、相关性、价值性、动态性的整合原则,打破区域、部门间的界限,从横向、纵向、防灾减灾全过程进行信息整合,形成一套较完善的信息整合体系。为进一步明确整合主体(人)及整合对象(防灾减灾信息)之间相互联系和作用的方式,还介绍信息整合的3种模式:对象关联模式、逻辑模式、综合模式。在实践中,可以根据资源、技术、需求等方面的具体情况,单独地或综合地利用该3种模式进行信息内容的整合。通过信息整合能提升防灾减灾信息利用的整体效能,有效地发挥信息资源在防灾减灾中的作用。