Concentrations and gas-particle partitioning of PCDD/Fs in the urban air of Dalian, China

PCDD/Fs in the urban air of Dalian,China were monitored with high-volume active sampler from November 2009 to October 2010.The concentration of Cl 4-8 DD/Fs ranged from 3065 to 49538 fg m-3,with an average of 10249 fg m-3.The international toxic equivalents(I-TEQ) value of that was 61.8 1182 fg m-3,with an average of 235 fg m-3,which was comparable to those in the other urban locations around the world.It was found that the Cl 4 8 DD/Fs appeared to be present mainly in the particle phase during winter,spring and autumn,while during summer which were dominantly in gas phase.The ratio of Cl 4-8 DD/Fs present in particle phase increased with the increasing level of chlorination.The concentrations of PCDFs and PCDDs decreased with the increase of chlorinated level,while the concentrations of 2,3,7,8-PCDDs congeners increased with the increase of chlorination level.The homolog profiles of the concentrations of PCDFs presented were higher than those of the PCDDs,which indicated the PCDD/Fs pollution source of the air in Dalian was characteristic for thermal source pollution.The correlation analysis of meteorological parameters with the concentrations of Cl 4-8 CDD/Fs was conducted using SPSS packages,and it was found that the ambient temperature and atmospheric pressure were important factors influence the concentration of PCDD/Fs in the air.The respiratory risk and intake dioxins of the residents around the sampling sites were studied in the paper.It was found that Junge-Pankow model was much more accurate in predicting the gas-particle partitioning behavior of PCDD/Fs homologues during winter,while the Harner-Bidleman model shows better agreement with the measured data during winter and summer.     

淀山湖表层水、沉积物和鱼体中有机氯农药的时空变化及人体暴露风险

有机氯农药(organochlorine pesticides, OCPs)是一类持久性有机污染物, 研究它们在城市近郊湖泊的污染状况, 有助于更好地了解其对湖泊水环境的影响. 研究了上海近郊淀山湖表层水、沉积物和鱼体中的OCPs污染状况及人体暴露的健康风险. 结果表明, 六六六(hexachlorocyclohexanes, HCHs)和滴滴涕(dichlorodiphenyltrichloroethanes, DDTs)分别是表层水和沉积物中的主要OCPs 污染物, OCPs 在淀山湖野生鱼体中也有检出. 淀山湖中HCHs 和DDTs 的来源主要是历史残留. 沉积物中的OCPs 浓度相对比较稳定, 但表层水中的浓度随采样时间有一定变化, 即丰水期浓度高于枯水期. 淀山湖进水区域的污染程度普遍高于出水区域. 考察了饮食摄入(食鱼和饮水)、呼吸和皮肤渗透(游泳) 3 种途径对人体暴露量的影响, 发现饮食摄入是DDTs和HCHs的主要暴露源. 淀山湖水环境已受到OCPs的影响, 但污染水平不高且不会产生健康风险.     

2006～2010年大连市区空气质量变化原因分析

2006～2010年,大连市区空气中可吸入颗粒物和二氧化硫浓度总体呈下降趋势,可吸入颗粒物浓度从0.094mg/m3,下降到0.058mg/m3,二氧化硫浓度从0.048mg/m3,下降到0.037mg/m3.原因首先是由于大连的污染减排取得了明显的成效,截止2010年底,8家电厂的脱硫工程全面完工;其次是由于全国范围的污染减排,使大环境变好,冬季受北部城市外来污染的影响下降,夏季来自山东半岛的污染也下降,即外来污染对大连的影响下降.大连市空气中二氧化氮浓度升高,其原因一是由于汽车尾气排放量的不断上升,二是由于电厂以及工业企业的污染减排缺少脱氮工艺;此外,大连市采暖期二氧化硫的污染主要是受冬季采暖燃煤的影响.     

大连地区航路与鸟类迁徙路线交叉冲突的探讨

为减少鸟击事件,通过对大连机场2011年鸟击事件的飞行阶段和飞行高度、季节规律、时间规律以及造成鸟击事件物种的分析,结合大连地区鸟类迁徙的规律,对大连地区航路与鸟类迁徙路线的交叉冲突点进行了探讨,并对大连地区迁徙鸟类容易造成鸟击的原因进行了分析,根据鸟类迁徙规律和飞行程序提出了应对措施的建议.     

137Cs tracing of lacustrine sediments in the Dalian Lake, Qinghai Province, China

Based upon the analysis of Cs and grain-size parameters, the total amounts of ¹³⁷Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of ¹³⁷Cs in the lacustrine sediments exhibits three ¹³⁷Cs activity maxima and one minimum. The major maximum corresponds to the global ¹³⁷Cs fallout in 1963; the two secondary maxima correspond to the leakage of the Chernobyl reactor in 1986 and complete desiccation of the lake in 1994, respectively. The minimum corresponds to aeolian deposition caused by extensive reclamation in the late 1980s and early 1990s. The 137Cs data set was used to evaluate average sedimentation rate of the Dalian Lake since 1963. The deposition was stable in 1963-1986 and 1994-1998, and it was rapid during 1986-1994. This preliminary study reveals that l37Cs has the same potential to trace environmental changes introduce by human interference in arid/semiarid regions as in humid regions.     

宝鸡市休闲保健游园环境NAI的定量评价和比较

目的 以宝鸡市为例,将城市休闲保健游园环境中空气负离子（NAI）作为研究对象,对其浓度进行定量评价和分析比较,遴选最佳城市休闲保健游园环境,为当地居民提供近距离的休闲保健游园场所.方法 用KEC-900正负离子测试仪测定中华石鼓园（Shigu Park）、宝鸡市植物园（BotanicGarden）、周礼文化主题公园（Chou Li Cultural Theme Park）、渭河生态公园（Weihe Ecol.Park）、杨家山农业观光园（Agricultural Sightseeing Garden）、渭河公园（Weihe Park）的NAI浓度,与室内（Rooms） NAI浓度进行比较,遴选出宝鸡市区有益于人体保健的休闲游园最佳环境.结果 观测结果显示,中华石鼓园NAI浓度最高,平均为1 515个/cm3（n=385）;其次是宝鸡植物园,平均浓度为1 071个/cm3（n=136）;周礼文化主题公园和渭河生态公园NAI平均浓度分别为884个/cm3（n=149）和825个/cm3（n=156）;杨家山农业观光园NAI平均浓度为544个/cm3（n=157）,渭河公园的NAI浓度平均为495个/cm3（n=168）,分别是室内NAI浓度（366个/cm3,n=130）的1.35～4.14倍,而且上述6处游园环境和室内环境NAI浓度,在P=0.005水平存在显著性差异.结论 城市公园环境是市民最好的休闲保健活动场所,中华石鼓园和宝鸡植物园,相对其他游园环境NAI浓度更高（＞1 010个/cm3）,相当有利于健康,不失为宝鸡市区休闲保健的最佳游园环境.     

天山北部拟南芥分布群落的物种多样性特征及生态适宜性分析

本文采用物种重要值、丰富度指数、多样性指数和均匀度指数对新疆北部的石河子、伊犁果子沟、额敏、阿勒泰等7个地区的拟南芥（Arabidopsis thaliana）生存群落的群落结构和物种组成进行了研究,比较了不同样地间的物种多样性和相似性指数,并采用生态位适宜度模型,分析了天山北部拟南芥生存群落的生态位适宜度及其限制因子。结果表明：研究区科、属、种结构较简单。天山中部4个样地均为草本群落,优势种相似,与其它3地不同。伊犁果子沟地区物种多样性最高,额敏地区其次,阿勒泰样地较低;总体上天山中部4个样地的物种多样性均不高,而其群落间物种相似性较高。天山中部4个样地与伊犁果子沟、额敏、阿勒泰3样地间的物种相似性均较差,但后3个样地间的物种相似性稍大。拟南芥生存群落的生态位适宜度较高,均在0.885以上,仅沙湾与独山子、伊犁果子沟之间达到了显著性差异（P〈0.05）,显示了拟南芥生存群落在天山北部较好的适应性。分析发现土壤养分（速效磷、速效钾）及土壤电导率是影响天山北部拟南芥种群分布、数量及重要性差异的主要小环境限制因子,但最终要受到水分因子的制约,降水、地理位置等大环境因素以及群落内物种相互关系具有重要作用,同时,拟南芥的分布与其生存群落的优势种,尤其与如新疆绢蒿的多年生草本依赖关系较为密切。     

东平湖硅藻群落结构特征及其与水环境的关系

东平湖位于淮海经济区北部,是国家南水北调东线工程的关键调蓄湖,其水环境状况对于调水水质安全具有重要意义.硅藻是指示湖泊水环境的敏感指标,在湖泊水质监测中有着广泛应用.为了解东平湖的水环境状况,2011年分季节对东平湖硅藻样品和水样进行了采集分析.研究表明:东平湖硅藻有16属43种,主要以部分附生和浮游种为主;优势属种有Achnanthes minutissima,Aulacoseira ambigua,Aulacoseira granulata,Fragilaria capucina v.vaucheriea,Synedra tenera,Synedra ulna v.acus等.冗余分析(RDA)结果共解释物种数据累计方差的28.1%;Monte Carlo检验表明,东平湖水体中COD,pH值、总P和深度是影响底栖动物群落分布最关键的环境因子(F=2.04~2.85,p0.05).总体来看,目前东平湖整体水质处于中营养及中营养向富营养方向转化之中,今后要特别注意湖区人类活动增强后对湖泊的污染,以确保南水北调输水水质的安全.     

Characteristics of strontium isotopes and their implications in the Qixing Cave of Guizhou,China

The strontium isotopic compositions (87Sr/86Sr) of samples including soils, bedrock, soil waters, drip waters and their corresponding speleothems in the Qixing Cave (QXC), Guizhou Province, China, were systemically measured and analyzed. The results indicate that there are significant Sr isotopic differences among samples. The mean 87Sr/86Sr ratios in drip water for the samples 1#, 4# and 9# were 0.709568, 0.709139 and 0.708761, respectively, which possibly result from different flow paths, residence times, and other hydrogeological processes in the unsaturated zone overlying QXC. Meanwhile, levels of 40.8%, 57.6% and 72.4% of Sr in drip waters for 1#, 4# and 9#, respectively, were derived from bedrock dissolution, which was calculated by the mixture model of the two end-members (soil and bedrock). There is, however, no positive correlation between the relative proportion from bedrock dissolution (δ13C value is 1.8‰) and drip water δ13CDIC values. The mean drip water δ13CDIC value in 1# is the heaviest (–4.5‰) with the lowest contribution rate of bedrock dissolution, whereas the value in 9# is the lightest (–9.3‰) with the highest contribution rate of bedrock dissolution. The proportion from host rock dissolution in 4# is higher than that in 1# and lower than that in 9#, while its mean drip water δ13CDIC value (–8.6‰) is higher than that of 9# and lower than that for 1#. This suggests that the prior calcite precipitation (PCP) processes in the unsaturated zone overlying the cave are responsible for the δ13CDIC value differences between different drip waters, and not bedrock dissolution. Furthermore, this study also demonstrates that the 87Sr/86Sr ratios of speleothems in the 1# and 4# mainly reflect the variation in the relative proportions from the soil system (soil water) and bedrock dissolution overlying the cave. It is, therefore, feasible to use the strontium isotopic signals of speleothems as an indicator for soil chemical weathering intensity, and consequently as a monsoon proxy in the study area.     

Concentrations, profiles and gas-particle partitioning of PCDD/Fs, PCBs and PBDEs in the ambient air of an E-waste dismantling area, southeast China

Polychlorinated diebenzo-p-dioxins （PCDDs）, polychlorinated diebenzofurans （PCDFs）, polychlorinated biphenyls （PCBs） and polybrominated diphenyl ethers （PBDEs） were monitored in the ambient air of Taizhou, an E-waste dismantling area of southeast China to evaluate their concentrations, profiles and gas-particle partitioning. The ∑PCDD/Fs concentrations ranged from 2.91 to 50.6 pg/ma, with an average of 14.3 pg/ma. The I-TEQs for PCDD/Fs were in the range of 0.20-3.45 pg/ma, with an average of 1.10 pg/ma, The ∑PCBs concentrations and TEQs ranged from 4.23 to 11.35 ng/ma, 0.050 to 0.859 pg（TEQ）/ma, respectively. The concentrations of ∑PBDEs ranged from 92 to 3086 pg/ma, with an average of 894 pg/ma, The pollution levels of PCDD/Fs, PCBs and PBDEs were higher than other urban sites, which may be associated with the E-waste dismantling activities. The PCDD/Fs were found exclusively in the particle phase whereas PCBs distributed dominantly in the gas phase. The gas-partilce partitioning was also assessed by correlating the gas-particle partition coefficient （Kp） with the subcooled liquid vapor pressure （pL^0）. The measured particulate sorptions of PCDD/Fs, PCBs and PBDEs were compared with the predictions from Junge-Pankow model and Koa absorption model. The Junge-Pankow model well estimated the particulate fractions of PCBs. However, it underestimated the sorptions of PCDD/Fs and overestimated the fractions of PBDEs. The predicted particulate fractions of PCDD/Fs and PCBs from Koa model fitted well with the measured data.     

西方造币技术知识的翻译、传播及其影响

笔者以《铸钱工艺》为研究重点,结合对《申报》等刊物相关内容的解读,探讨了西方机器造币技术知识的翻译、传播及其影响的情况.     

Formation and causes of NO<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> pollution on the east side of the Taihang Mountains in China

Tropospheric column amounts of NO 2 from OMI/Aura products were applied to investigate the seasonal variation of NO x on the east side of the Taihang Mountains (ESTM) in China. The NO 2 concentration varied seasonally, with winter maxima and summer minima. To explore the causes of the heavy NO 2 pollution in this region, wind field simulations were conducted by using the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5). MM5 simulations showed that wind directions in the ESTM region were dominated by northeasterly and northwesterly winds throughout the year and to a lesser degree by southwesterlies. Elevated NO 2 concentrations (higher than 50×10 15 molec/cm 2 ) occurred in three meteorological situations: convergent wind fields (5 days), northeasterly winds (2 days), and calm days (1 day) in January. Although the local anthropogenic NO x emission strength was not so high as that in other developed areas, the calms and frequent occurrence of convergent wind fields, as well as unfavorable terrains for diffusion, resulted in the accumulation of atmospheric pollutants and hence heavy NO x pollution. Furthermore, long-distance NO x transportation from the Beijing-Tianjin-Tangshan region to the ESTM area could be seen when the wind was from a northeasterly direction, especially under high wind speeds.