微塑料在哺乳动物的暴露途径、毒性效应和毒性机制浅述

微塑料广泛存在于大气、土壤和水体环境中,其对人体的危害正受到广泛关注.本文阐述了当前对微塑料在哺乳动物的暴露途径、毒性作用和毒性机制的认识.空气-呼吸系统、食物/饮水-消化系统以及洗漱/护肤产品-皮肤等都是目前最常见的微塑料人体暴露途径,其中消化系统暴露是最主要的方式.目前的研究显示肠道、肝脏和肾脏是主要的微塑料富集部...     

高速公路边坡生态防护系统探讨

分析了高速公路边坡特点及其侵蚀机理,阐述了过去我国边坡防护方式的不足之处,提出了边坡防护类型选择原则及生物防护方式的优势所在,同时还指出当前边坡防护中存在的问题.     

利用浑浊度推算含沙量方法的限制性与适用性研究

通过对利用浑浊度与含沙量的相关关系来推算含沙量的方法的研究,发现此方法有两个限制因子,一是泥沙粒径,二是水中盐等其他杂质。研究结果表明,浊度法对于低含沙量、粒径小的水样测量精度高。     

钻井水溶开采地面沉降的机理分析与控制对策措施研究

本文通过对某矿钻井水溶开采的溶腔稳定性、覆岩稳定性和地表移动变形分析计算,探讨了该矿产生溶腔失稳和地面沉降的机理,并提出了控制溶腔失稳和地面沉降的对策措施,对钻井水溶开采矿山有一定的借鉴价值。     

船舶设备事故中的人为因素分析与控制研究

根据设备维修系统设备维修的人为失误环节和船员失误分析模式以及轮机管理人员具有明感知设备的运行状态、隐感知设备的故障趋势等特点,实施有效管控措施。结合航运市场特性,基于设备可靠度,提出风险性和经济性的维修方式策略,可大幅提高航运公司的安全航运水平和经济效益。利用维修系统的信息流,建立了船舶设备维修管理信息系统,整合设备运行状态、船员的综合素质状态及组织管理信息,以便于阻断导致事故发生的事件链,提高航运公司的船舶运输安全。     

Environmental ozone exposure and oxidative DNA damage in adult residents of Florence, Italy

In 71 adults residing in Florence, Italy, enrolled in a prospective study, we investigated the correlation between individual levels of oxidative DNA damage detected by the Comet assay in circulating lymphocytes, and a specific ozone exposure score calculated in 10 different time-windows (0-5 to 0-90 days) before blood drawing, based on daily measurements provided by the local environmental monitoring system.Overall, statistically significant positive correlations between average ozone concentrations and DNA damage emerged in almost all time-windows considered; correlations were more evident among males, non-smokers, and traffic-exposed workers. Multivariate regression analyses taking into account selected individual characteristics, showed an independent effect on DNA damage of average ozone concentrations in the last 60-90 days before blood drawing. Local residents showed a divergent pattern with correlations restricted to shorter time-windows.Our results suggest that ozone concentrations at ground levels modulate oxidative DNA damage in circulating lymphocytes of residents of polluted areas.     

Earthquake recovery of historic buildings: exploring cost and time needs

Disaster recovery of historic buildings has rarely been investigated even though the available literature indicates that they face special challenges. This study examines buildings' recovery time and cost to determine whether their functions (that is, their use) and their status (historic or non-historic) affect these outcomes. The study uses data from the city of San Francisco after the 1989 Loma Prieta earthquake to examine the recovery of historic buildings owned by public agencies and non-governmental organisations. The results show that recovery cost is affected by damage level, construction type and historic status, whereas recovery time is affected by the same variables and also by building function. The study points to the importance of pre-incident recovery planning, especially for building functions that have shown delayed recovery. Also, the study calls attention to the importance of further investigations into the challenges facing historic building recovery.     

The Role of Wetlands for Mitigating Economic Damage from Hurricanes

Coastal communities along the United States coast often experience significant economic damage resulting from the impacts of tropical storms and hurricanes. Research suggests that certain factors that affect economic damages are increasing the vulnerability of coastal communities. Population growth, which increases vulnerability by placing valuable lives and assets in the path of storms, is expected to increase. Climate change has the potential to cause more frequent and intense storms, and coastal wetland loss is contributing to the vulnerability of coastal populations. Wetlands conservation and restoration is often advocated for as a means of reducing the impacts of coastal storms. The relationship between wetlands and storm surge energy is understood relatively well in physical terms, but very little economic analysis has been conducted to estimate the degree to which wetlands reduce economic impacts. Using factor analysis, the relationships among coastal populations, wetlands, storm intensity, and economic damage are explored. The factor analysis suggests that wetland presence is associated with a reduction in economic damages from coastal storms. Factor score analysis suggests that the proportion of damage explained by wetland presence is smaller for more intense storms. These results are consistent with those found in the physical science literature and have potentially large consequences for how wetlands are used in risk reduction.     

年度地震重点监视防御区地震保险净费率的计算

根据我国年度地震重点监视区13年的预报结果和实际发生地震的结果,研究了这些地区地震保险净费率的计算方法。作为例子,给出了Ⅱ类地区基本烈度为Ⅵ度地区多层混凝土楼板砖结构Ⅶ度设防的建筑物的地震保险净损失率的计算结果。结果表明,我国年度地震重点监视区的地震保险净费率明显高于同类研究中不考虑其特殊地震危险性的结果。这一结果表明,中国的年度地震重点监视区是地震保险研究中应当给予特别关注的地区。     

纯弯荷载下厚型钢结构防火涂层破损的试验研究和数值分析

厚型钢结构防火涂层因其耐火性好、性能稳定而成为最常用的防火保护形式之一,但厚型防火涂层易在地震和冲击等作用下发生破损和脱落,这将影响钢结构的抗火性能。为了认识厚型钢结构防火涂层的破损模式,本文对涂有厚型防火涂料的钢板件进行了纯弯荷载试验,运用有限元分析软件AN SY S对试验全过程进行了模拟分析,并与试验结果相对比。结果表明:受弯构件压区涂层的破损模式主要为涂层-钢板界面破损,拉区涂层的破损模式与涂层厚度有关,当涂层厚度较薄时,主要为涂层内部拉裂,涂层厚度较厚时,主要为涂层-钢板界面破损;涂层厚度越厚,界面破损出现得越早;若在涂层上贴置应变片,会使涂层的界面裂缝和横向裂缝提早出现。