沈阳市区大气颗粒物元素组分及其分布

本研究采用美国安德逊五段冲击式采样器进行大气颗粒物采样，用中子活化法进行分析，获得４３种元素质量浓度，并求得各种元素的质量中值直径和几何标准差。     

地磁Z分量整点值空间相关法在江苏地区地震预报中的初步应用

应用江苏地磁台站Ｚ分量整点值资料,研究了江苏地区Ｚ分量整点值的相关性及在江苏地区地震预报中的作用,给出了该法在江苏地区的异常判据指标,并应用该指标提取了１９９０～１９９７年的三个异常,其中两个异常有地震对应。     

Very low versus undetectable maternal serum alpha-fetoprotein values and fetal death

Very low maternal serum alpha-fetoprotein (MSAFP) levels (<10 ng/mL) are known to be associated with non-viable pregnancies, including conditions such as fetal death, molar pregnancies, and non-pregnancies. There has not been agreement, however, as to whether very low MSAFP levels indicate already existing fetal deaths or are actually predictive. We analysed 230 pregnancies with MSAFP levels <10 ng/mL from among 15 807 women (1.5 per cent) screened consecutively during a three-year period and identified 26 non-viable pregnancies, 22 of which were diagnosed sonographically as part of the screening process (17 missed abortions, 3 blighted ova, 2 non-pregnancies). Furthermore, 20 of these 22 pregnancies were associated with essentially undetectable MSAFP levels (<5 ng/mL). Our data indicate that pregnancies with MSAFP values <5 ng/mL are the group most strongly associated with fetal non-viability and that very low MSAFP values are not strongly predictive for fetal death.     

城市生活污水厌氧生物处理发展现状

回顾了国内外污水厌氧生物处理工艺的发展情况,着重分析了中国城市污水的特点以及厌氧生物处理工艺在城市生活污水处理中的应用情况。     

Analysis of heavy metal distribution in superficial estuarine sediments (estuary of Bilbao, Basque Country) by open-focused microwave-assisted extraction and ICP-OES

Open-focused microwave-assisted extraction and ICP-OES determination of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn from surface sediments of the estuary of Bilbao (Basque Country, North of Spain) was carried out. All the samples were collected at three different tributaries of the estuary (Asua, Galindo and Nerbioi-Ibaizabal) every two months during 1999. The digestion procedure was proposed from the conclusions of a fractionated factorial design, and the precision and accuracy of the method was verified using a certified reference sediment (RTC008-050). The results of the analysis were statistically treated by means of principal component analysis and correlation analysis. The principal component analysis of sediment data (32 samples × 9 metals) indicated different patterns of contamination regarding the tributary and sampling station. The two main patterns observed were a steady increment of the metal concentration along all the campaigns in the samples collected in the Galindo River and a seasonal variation in the Nerbioi-Ibaizabal River, with higher metallic content during summertime and lower content during wintertime.     

What is the lesson from the unprecedented event over antarctica in 2002

Varotsos (2002a,b), suggested that both the smaller-sized ozone hole over Antarctica and its splitting in two holes in September 2002 occurred due to an unprecedented major sudden stratospheric warming caused by very strong planetary waves propagated in the southern hemisphere. Subsequently, a NASA press release of December 6, 2002, also reported the prevalence of very strong planetary waves in Antarctica. The aim of this Letter is to further discuss the morphology of the Antarctic ozone hole, to detect the causes that allowed the Antarctic stratosphere to exhibit this exceptional warming and to examine what it denotes about its mechanisms. Concerning the morphology, among the principal findings is that the ozone hole split occurred not only in the stratosphere but extended in the lower altitudes (upper troposphere). As to the causes of the major sudden stratospheric warming of 2002, a comparison with the previous warmings in Antarctica since 1964 is made. The smaller-sized Antarctic ozone hole of 2002 is approximately equal to that of 1988 when a strong sudden stratospheric warming occurred. If only the destruction of ozone by chlorofluorocarbons resulted in the delayed sudden stratospheric warmings in Antarctica, then the early sudden stratospheric warmings of 1988 and 2002 would not have occurred, since chlorofluorocarbon loading of the stratosphere has remained relatively stable in recent years. Furthermore, it appears that the El Nino characteristics in 1988 and 2002 are not similar.     

一种新型复合球填料在低浓度污水再生回用中的应用研究

新型复合球填料为沸石与悬浮球填料的有机组合体,密度约为0.92～0.97g/cm3,比表面积为711～1185m2/m3,表面粗糙,物化性能稳定.在曝气量为20∶1,停留时间为6 h时,装有新型复合球填料的反应柱挂膜容易,成膜时间短,膜不易脱落,且生物相丰富.膜成熟时对生活污水中的氨氮和COD都有很好的去除效果,出水氨氮浓度≤2 mg/L,去除率≥93%;出水COD浓度≤22 mg/L,去除率≥80%.新型复合球反应柱在稳定状态处理低浓度的二级出水时,出水氨氮浓度≤2 mg/L,去除率≥89%,出水COD浓度为10～36 mg/L,去除率为48%～81%.出水水质符合GB50335-2002标准.     

Examination of dioxin fluxes recorded in dated aquatic-sediment cores in the Kanto region of Japan using multivariate data analysis

Past dioxin (coplanar polychlorinated biphenyl (Co-PCB), 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin (PCDD) and 2,3,7,8-substituted polychlorinated dibenzofuran (PCDF)) fluxes recorded in dated aquatic-sediment cores were analyzed using principal component analysis (PCA). The data set consisted of samples from four cores collected from the Kanto region of Japan. Time trends and spatial differences in the dioxin flux were examined, and the potential relationship to emission sources was investigated. Twenty-five compounds and 58 core slices, corresponding to the later half of the 20th century, were subjected to the analysis. The PCA of both log-transformed and maximum-value-standardized data successfully divided the dioxin compounds into a small number of groups, and three similar clusters of Co-PCBs, PCDDs and penta- to hepta-CDFs were identified. PCB formulations used in the past are judged to have been responsible for the major part of the Co-PCB flux recorded in the sediment cores. However, the relationship to emission sources needs further investigation. It is suggested that most 2,3,7,8-substituted PCDDs and PCDFs are different from Co-PCBs in their emission sources or movements in the environment. The subcore clusters obtained from the PCA of log-transformed data show that the cores from different sampling areas exhibited distinct dioxin fluxes and compositions. Common time trends among the cores were more effectively summarized by the PCA of maximum-value-standardized data focusing on relative time trends. PC scores show that recently the flux of each dioxin compound in the four cores has been generally declining after having reached a peak.     

低温等离子体治理H2S污染的实验研究

低温等离子体技术是一种高效、快速的污染消除技术，国内外都在对其进行广泛而深入的研究。采用脉冲电晕放电等离子体对空气中的硫化氢进行降解研究，探索了、脉冲峰压、脉冲频率、气体流量以及气体初始浓度对净化效果的影响，气体浓度由气相色谱仪测定。结果表明，脉冲电晕放电可以有效消除硫化氢污染，净化率随脉冲峰压和脉冲频率的增加而提高，随气体初始浓度和流量的增加而下降，且在初始浓度360mg／m^2、流量1200mL／min、脉冲峰压30kV、脉冲频率80Hz的条件下，处理后的气体中已检测不到H2S，根据色谱检测限（0．29mg／m^3）计算出的净化率≥99．92％。采用离子色谱对产物进行了定性分析，发现H2S经放电处理后主要产物为SO2和SO3。     

低浓度甲醛促进K562细胞增殖的分子机制探究

低浓度甲醛(Formaldehyde,FA)可以促进细胞增殖.本实验选用K562细胞为实验对象,用不同浓度的甲醛溶液处理细胞,探究其中可能存在的分子机制.测定细胞活力及胞内氧化损伤程度后,发现当甲醛浓度为75μmol·L~(-1)时,细胞增殖率上升(p0.05或p0.01),Warburg效应中的丙酮酸激酶M2型同工酶(PKM2)、葡萄糖转运蛋白1(GLUT1)、乳酸脱氢酶A(LDHA)、葡萄糖和乳酸含量上升(p0.05);此外,细胞周期调控因子Cyclin D-cdk4与转录因子E2F1含量也上升(p0.05).同时,细胞内氧化损伤加强,其中活性氧簇(reactive oxygen species,ROS)含量上升(p0.01),还原型谷胱甘肽(glutathione,GSH)下降(p0.05).然而,在加入抗氧化剂VE后,氧化损伤程度减弱,细胞增殖率降低,PKM2、GLUT1、LDHA、葡萄糖、乳酸,Cyclin D-cdk4、E2F1含量均下降.结果表明低浓度甲醛可能通过氧化应激诱导Warburg效应和影响细胞周期调控因子两条途径促进细胞的增殖.