青藏高原古里雅冰芯中痕量元素镉记录的大气污染:1900-1991

对取自青藏高原古雅冰帽的冰芯上部２０ｍｎ的样品中有毒金属镉反映的大气污染进行了研究,利用电感耦合等等离子体质谱仪对镉的浓度进行了检测,镉的浓度在２．２８－３０１ｐｇ．ｍｌ＾－１,平均为５１ｐｇ．ｍｌ＾－１,镉的浓度高于极地雪冰相应的时间的浓度。     

RISK OF EXTREME EVENTS IN A MULTIOBJECTIVE FRAMEWORK1

ABSTRACT: This paper summarizes advances made in risk-based decisionmaking in water resources through use of the partitioned multiobjective risk method (PMRM). (Risk is a measure of the probability and severity of adverse effects.) In the PMRM, the risk of extreme events is differentiated from risk involving less extreme damage severity and is evaluated within a multiobjective framework. Study of the extreme-event risk function f₄(*) has addressed the following issues: methods for calculating f₄(*); the sensitivity of f₄(*) to various parameters, particularly to the partitioning point of the extreme-event range and the selection of probability density functions; insight provided by the statistics of extremes; and the impact of f₄(*) on risk management, for example, in the application of the PMRM to water resources problems. In particular, this paper shares with the reader recent research results on the PMRM, the relationship between the statistics of extremes and the conditional expected value, derived formulas for f₄(*), distribution-free estimates of f₄(*), documented case studies in dam safety, and future research directions.     

从世界银行对二滩水电站环境影响评估中得到的启示

本文介绍了二滩水电站环境影响评价，以及世界银行评估过程中专家提出的一系列环境问题，并结合我院１０多年来的环境影响评价工作简述几点启示，供参考。     

Size distribution, characteristics and sources of heavy metals in haze episod in Beijing

Size segragated samples were collected during high polluted winter haze days in 2006 in Beijing, China. Twenty nine elements and 9 water soluble ions were determined. Heavy metals of Zn, Pb, Mn, Cu, As, Cr, Ni, V and Cd were deeply studied considering their toxic effect on human being. Among these heavy metals, the levels of Mn, As and Cd exceeded the reference values of National Ambient Air Quality Standard （GB3095-2012） and guidelines of World Health Organization. By estimation, high percentage of atmospheric heavy metals in PM2.5 indicates it is an effective way to control atmospheric heavy metals by PM2.5 controlling. Pb, Cd, and Zn show mostly in accumulation mode, V, Mn and Cu exist mostly in both coarse and accumulation modes, and Ni and Cr exist in all of the three modes. Considering the health effect, the breakthrough rates of atmospheric heavy metals into pulmonary alveoli are： Pb （62.1%） 〉 As （58.1%） 〉 Cd （57.9%） 〉 Zn （57.7%） 〉 Cu （55.8%） 〉 Ni （53.5%） 〉 Cr （52.2%） 〉 Mn （49.2%） 〉 V （43.5%）. Positive matrix factorization method was applied for source apportionment of studied heavy metals combined with some marker elements and ions such as K, As, SO42- etc., and four factors （dust, vehicle, aged and transportation, unknown） are identified and the size distribution contribution of them to atmospheric heavy metals are discussed.     

Polybrominated diphenyl ethers in background surface soils from the Yangtze River Delta (YRD), China: occurrence,sources, and inventory

Purposes  

Very few data for polybrominated diphenyl ethers (PBDEs) were available in the Yangtze River Delta (YRD), one of the most developed and urbanized region in China. In this study, Chongming Island, located at the estuary of the Yangtze River, was selected as background area to investigate the occurrence, sources, and inventory of PBDEs.     

CO3O4/介孔分子筛催化剂对苯催化完全氧化的研究

分别以介孔分子筛MCM-41、MCM-48、SBA-15为载体,采用等体积浸渍法制备了氧化钴/介孔分子筛催化剂,利用N2吸附、X射线衍射、程序升温还原等技术对催化剂进行了表征,考察了Co3O4的负载量及载体的孔结构对催化剂完全催化氧化苯的性能的影响.结果表明,Co3O4的负载量为20%时,催化剂的催化活性最好;载体的孔径和催化剂的可还原性能是影响催化活性的主要因素,催化剂活性顺序为Co3O4/SBA-15>Co3O4/MCM-41>Co3O4/MCM-48.     

易燃、易爆(有毒)重大危险源(罐区)泄漏物扩散模型及数值模拟

在研究易燃、易爆、有毒的重大危险源和泄漏物扩散模型的基础上,建立了易燃、易爆、有毒物三维数值模拟程序,得到了复杂地形条件下关键点的有害物浓度历史和有害物的时空分布     

柴油车排气微粒捕集用复合金属丝网的制备与性能研究

论述了用于柴油车排气微粒捕集器的复合金属丝网的制备和测试过程 ,讨论了丝网层数和涂层负载对复合金属丝网过滤性能的影响 ,并分析了其捕集机理     

加氢装置高压串低压风险分析及对策

针对加氢装置高压串低压的特点,分析讨论了其存在的火灾、爆炸、人身伤害、中毒等风险,针对这些风险提出对应的安全防范措施。     

Groundwater arsenic removal by coagulation using ferric(Ⅲ)sulfate and polyferric sulfate: A comparative and mechanistic study

Elevated arsenic(As) in groundwater poses a great threat to human health. Coagulation using mono- and poly-Fe salts is becoming one of the most cost-effective processes for groundwater As removal. However, a limitation comes from insufficient understanding of the As removal mechanism from groundwater matrices in the coagulation process, which is critical for groundwater treatment and residual solid disposal. Here, we overcame this hurdle by utilizing microscopic techniques to explore molecular As surface complexes on the freshly formed Fe flocs and compared ferric(III) sulfate(FS) and polyferric sulfate(PFS)performance, and finally provided a practical solution in As-geogenic areas. FS and PFS exhibited a similar As removal efficiency in coagulation and coagulation/filtration in a two-bucket system using 5 mg/L Ca(ClO)_2. By using the two-bucket system combining coagulation and sand filtration, 500 L of As-safe water( 10 μg/L) was achieved during five treatment cycles by washing the sand layer after each cycle. Fe k-edge X-ray absorption near-edge structure(XANES) and As k-edge extended X-ray absorption fine structure(EXAFS) analysis of the solid residue indicated that As formed a bidentate binuclear complex on ferrihydrite, with no observation of scorodite or poorly-crystalline ferric arsenate. Such a stable surface complex is beneficial for As immobilization in the solid residue, as confirmed by the achievement of much lower leachate As(0.9 μg/L–0.487 mg/L)than the US EPA regulatory limit(5 mg/L). Finally, PFS is superior to FS because of its lower dose, much lower solid residue, and lower cost for As-safe drinking water.