Assessing the inhalation cancer risk of particulate matter bound polycyclic aromatic hydrocarbons (PAHs) for the elderly in a retirement community of a mega city in North China

Assessment of the health risks resulting from exposure to ambient polycyclic aromatic hydrocarbons (PAHs) is limited by the lack of environmental exposure data among different subpopulations. To assess the exposure cancer risk of particulate carcinogenic polycyclic aromatic hydrocarbon pollution for the elderly, this study conducted a personal exposure measurement campaign for particulate PAHs in a community of Tianjin, a city in northern China. Personal exposure samples were collected from the elderly in non-heating (August–September, 2009) and heating periods (November–December, 2009), and 12 PAHs individuals were analyzed for risk estimation. Questionnaire and time-activity log were also recorded for each person. The probabilistic risk assessment model was integrated with Toxic Equivalent Factors (TEFs). Considering that the estimation of the applied dose for a given air pollutant is dependent on the inhalation rate, the inhalation rate from both EPA exposure factor book was applied to calculate the carcinogenic risk in this study. Monte Carlo simulation was used as a probabilistic risk assessment model, and risk simulation results indicated that the inhalation-ILCR values for both male and female subjects followed a lognormal distribution with a mean of 4.81?×?10^?6 and 4.57?×?10^?6, respectively. Furthermore, the 95 % probability lung cancer risks were greater than the USEPA acceptable level of 10^?6 for both men and women through the inhalation route, revealing that exposure to PAHs posed an unacceptable potential cancer risk for the elderly in this study. As a result, some measures should be taken to reduce PAHs pollution and the exposure level to decrease the cancer risk for the general population, especially for the elderly.     

试论黄淮海地区的自然资源及国家级作物商品基地的建设

根据中国主要农业区——黄淮海地区的自然和社会经济条件,分析了该区小麦、玉米、大豆、棉花等在气候-土壤生态适应性的基础上,采用逐级生产力估算方法,计算出四大作物的商品量,论证了该地区建设为全国性四大作物商品基地的可能性。     

利用红山单台研究邢台震区尾波(Qc)衰减特征

利用红山数字地震台记录到的,自2001年3月到2006年7月近震波形资料,采用从i的尾波单次散射模型计算了该台站周围50 km内的尾波Qc值;该范围代表了邢台震区的地下介质的特征,经多地震拟合后得出尾波与频率的衰减关系.并给出震区的尾波Qc值随时间的变化结果,发现在邢台2002年4月22日的M5.0级地震前后尾波Qc值由低升高然后再降低.     

New approach to studies of heavy metal redistribution in soil

The bioavailability and mobility of heavy metals in soils is dependent upon redistribution processes between solution and solid phases and among solid-phase components. This paper reviews the definitions and applications of two newly developed parameters, the redistribution index and the reduced partitioning parameter, in quantifying redistribution processes of heavy metals in contaminated soils. The redistribution index depicts the removal/attainment of metal-contaminated soils from/to the fractional distribution pattern characteristic of non-amended soils, while the reduced partitioning parameter quantifies the relative binding intensity of heavy metals in soils. Over time, metal salt-spiked and sludge-amended soils approached the fractional distribution pattern of non-amended soils. The rates of redistribution of metals and their binding intensity in soils were affected by the metal species, loading levels and soil properties. Metals in contaminated soils at low loading levels approach the fractional distribution pattern of non-amended soil more rapidly than those at high loading levels. The sequence order of approach by metals to the fractional distribution pattern of non-amended soil was: Cd>Cu>Ni=Zn>Cr. In both non-amended and contaminated soils, Cr had the highest binding intensity, Cd the lowest, and Cu, Ni and Zn, intermediate values. In addition to our own data, primarily on metal salt-spiked soils, these two indices are also used to evaluate redistribution processes of heavy metals in sewage sludge-amended soils from other published reports.     

新装修居室空气中甲醛浓度分析

目的 探讨装修后居室室内空气中甲醛浓度随时间的变化规律。方法 于2004年3-8月选择装修材料不同的2套新装修住宅，采用盐酸副玫瑰苯胺比色法，跟踪分析呼和浩特市2套居民新装修房屋室内空气甲醛含量。结果 铺复合木地板的A房空气中甲醛浓度比铺耐磨砖地板的B房空气中甲醛浓度约高17％；从装修完毕起，至少要经过6个月，室内空气中甲醛浓度才基本降至符合国家标准的水平；在连续监测过程中也发现，若室温升高，室内空气中甲醛浓度也会略有上升。结论 复合木地板释放的甲醛不容忽视；装修后6个月，室内空气中甲醛浓度才能降到容许范围。     

电子束烟气脱硫技术工业化示范

成都电厂电子束烟气脱硫示范工程处理该厂２００ＭＷ机组锅炉的３０万Ｎｍ＾２／ｈ烟气。其脱硫率及脱硝率均超过８０％及１０％设计值，处理过程为干法，无废水废渣，副产品硫铵可用作化肥，过程对烟气ＳＯ２浓度及烟气量的变化有较好的适应性和负荷跟踪性。     

黑石礁湾潮交换的数值研究

采用欧拉－拉格朗日方法对黑石礁湾水交换能力进行了数值研究。根据理论分析，潮流速度场的剪变和潮流迟角的空间分布的不均匀性导致水质点在周期性潮流场中产生净漂移，从而引起相邻水体之间发生交换。数值计算结果表明，黑石礁湾的水体具有较强的交换能力，有利于湾内水体的更新。     

抛物形件用软凸模拉深成形

分析了抛物形件用软凸模拉深过程,用聚氨酯橡胶凸模能简化抛物形件的制造工艺,有效地防止拉裂、起皱和回弹,给出了软凸模拉深系数和合适的软模硬度。     

LFSA-GC技术测定水体臭气

介绍了一种水体臭气的定量测定方法—单向一次性吹脱测臭 (LFSA -GC)技术 ,并用该方法对武汉东湖水体的一种致臭物质geosmin进行了定量测定。