珠江三角洲两条主要河流沉积物中的典型内分泌干扰物污染状况

为了调查珠江三角洲河流沉积物中典型内分泌干扰物的污染状况,采用超声提取-衍生化-GC/MS法研究了双酚A(BPA)、雌酮(E1)、雌二醇(E2)、己烯雌酚(DES)、17α-乙炔雌二醇(EE2)、雌三醇(E3)等典型内分泌干扰物在珠江广州河段和东江东莞河段表层沉积物中的质量分数水平、分布特征,并对其来源进行了分析。结果显示,BPA在所有样品中均有检出,E1和E2的检出率分别为72%和61%,其质量分数(以干质量计)分别在14.3～429.5 ng.g-1之间(中值为79.5 ng.g-1)、<1.3～10.9ng.g-1之间(中值为3.4 ng.g-1)和<0.9～2.6 ng.g-1之间(中值为1.6 ng.g-1);其余几种雌激素均未被检出。东江东莞河段沉积物中BPA的污染水平整体高于珠江广州河段,而天然雌激素的污染状况则是珠江广州河段更为严重。3种化合物的质量分数总体呈现出沿河口方向降低的分布特征,这可能与沿岸工业废水和生活污水不规则排放以及水动力条件有关。BPA、E1、E2的质量分数均与沉积物总有机碳(TOC)质量分数呈正相关,表明有机质是控制沉积物中内分泌干扰物分布的一个重要因素。     

珠江三角洲两条主要河流沉积物中的典型内分泌干扰物污染状况

为了调查珠江三角洲河流沉积物中典型内分泌干扰物的污染状况,采用超声提取-衍生化-GC/MS法研究了双酚A（BPA）、雌酮（E1）、雌二醇（E2）、己烯雌酚（DES）、17α-乙炔雌二醇（EE2）、雌三醇（E3）等典型内分泌干扰物在珠江广州河段和东江东莞河段表层沉积物中的质量分数水平、分布特征,并对其来源进行了分析。结果显示,BPA在所有样品中均有检出,E1和E2的检出率分别为72%和61%,其质量分数（以干质量计）分别在14.3～429.5 ng.g-1之间（中值为79.5 ng.g-1）、〈1.3～10.9ng.g-1之间（中值为3.4 ng.g-1）和〈0.9～2.6 ng.g-1之间（中值为1.6 ng.g-1）;其余几种雌激素均未被检出。东江东莞河段沉积物中BPA的污染水平整体高于珠江广州河段,而天然雌激素的污染状况则是珠江广州河段更为严重。3种化合物的质量分数总体呈现出沿河口方向降低的分布特征,这可能与沿岸工业废水和生活污水不规则排放以及水动力条件有关。BPA、E1、E2的质量分数均与沉积物总有机碳（TOC）质量分数呈正相关,表明有机质是控制沉积物中内分泌干扰物分布的一个重要因素。     

酚类内分泌干扰物在长江鱼体血浆中的生物富集

内分泌干扰物(Endocrine disrupting chemicals, EDCs)广泛存在于水环境,可在生物体内富集,具有潜在生态和健康风险.本研究选取双酚A(BPA)、辛基酚(4-t-OP)、雌酮(E1)、17β-雌二醇(E2)和炔雌醇(EE2)共5种酚类EDCs,分别测定其在长江中下游地表水和鱼体血浆中的含量及生物富集因子(Bioaccumulation factor, BAF),并结合血浆BAF预测模型对其生物富集能力进行评价.结果表明,BPA、4-t-OP和E1污染最为普遍,在地表水和鱼体血浆中检出率均超过50%,而其它两种EDCs(E2和EE2)在水体和鱼体血浆中的检出率和浓度均较低.综合检出频率和含量来看:BPA 4-t-OP E1 E2、EE2,5种酚类EDCs在水体中的最大浓度分别为99.7、22.3、2.47 ng·L~(-1)、ND(未检出)和ND,在鱼体血浆中的最大浓度分别为172、91.5、21.1、5.34、5.90 ng·mL~(-1).检出的3种酚类EDCs(BPA、4-t-OP和E1)的log BAF范围分别为2.29—4.20、3.18—4.18和3.29—3.75,表明鱼体血浆对酚类EDCs具有较高的生物富集潜能.对比模型预测的log BAF,实测的log BAF值明显较高,差异的产生与模型建立的前提假设、水温和溶解氧等因素密切相关.本研究有助于认识长江中下游鱼体中酚类EDCs的生物富集特征,并为其生态风险评价和管控提供依据.     

黄浦江上游水源地中31种内分泌干扰物的分布特征以及生态风险评价

本文研究了雄激素、雌激素、孕激素、糖皮质激素和工业化合物等5类31种环境内分泌干扰物(endocrine disrupting chemicals, EDCs)在黄浦江上游水源地中的空间分布特征,并采用风险熵值法(risk quotient, RQ)对水体中EDCs的生态风险进行了评价.黄浦江上游水源地9个采样点糖皮质激素和孕激素均未检出,工业化合物双酚类检出率100%.大多物质最高检出浓度10 ng·L~(-1),而双酚A (BPA)检出浓度最高(26.00—64.32 ng·L~(-1)).黄浦江以工业化合物和雌激素类物质污染为主,BPA为各采样点的主要污染物.莲西大桥EDCs总浓度最高(103.66 ng·L~(-1)),水库入口总浓度最低(40.16 ng·L~(-1)).太浦河上游工业化合物类浓度较下游高,雌激素类最高浓度检出点为汾湖大桥(11.70 ng·L~(-1)).与国内外地表水中EDCs检出浓度比较,黄浦江上游水源地中EDCs处于中低等污染水平.对己烯雌酚(DES)、雌三醇(E3)、BPA、双酚S (BPS)等4种EDCs进行生态风险评价,RQ范围为0.006-2.5,BPS表现出较高的环境风险(RQ=2.5).     

污水处理厂中典型内分泌干扰物的去除效果研究

内分泌干扰物(Endocrine Disruption Chemicals,EDCs)在水中极低浓度下即会引起水生生物生殖发育、神经和免疫系统的异常,对人群的健康危害不容忽视。EDCs在污水厂中具有低浓度、难去除的特点,为进一步阐明污水处理厂不同处理工艺对此类EDCs的去除效果,采用化学分析法(气质联用法)和生物学方法(H295R和MVLN细胞实验法)分析东莞市2个城市污水处理厂中8种典型EDCs的分布特征和去除效果。结果显示,两污水厂进水中壬基酚(Nonlyphenol,NP)、辛基酚(Octylphenol,OP)、双酚A(Bisphenol A,BPA)浓度较高,NP质量浓度分别高达10 782 ng·L~(-1)和2 664 ng·L~(-1),而雌激素类物质雌酮(Estrone,E1)、雌二醇(17β-Estradiol,E2)与雌三醇(Estriol,E3)、17α-乙炔基雌二醇(17α-Ethinglestradiol,EE2)、己烯雌酚(Diethylstilbestrol,DES)浓度较低,经处理后,去除效率均超过90%。两污水厂进水及出水处理后H295R细胞内雌二醇(E2)水平显著升高,睾酮(Testosterone,T)水平呈下降趋势,类固醇合成基因HMGR、CYP11B2和CYP19表达量显著增加。MVLN细胞试验结果显示,两污水厂出水中雌激素当量(Estradiol Equivalency quotient,EEQ)分别达19.25ng·L~(-1)和14.21 ng·L~(-1)。本研究表明,即使化学分析结果显示EDCs去除率高达90%,且出水中雌激素化合物低于检出限,但是出水中类固醇激素干扰活性及雌激素活性依然存在。类固醇激素水平与水中酚类物质浓度没有显著相关性,A、B两个污水厂出厂水中除酚类化合物外,其他产生雌激素效应的化合物或类固醇合成干扰物也不容忽视。     

对活性污泥中6种内分泌干扰物的定量测定

针对活性污泥中6种内分泌干扰物（Endocrine Disrupting Compounds,EDCs）：双酚A（BPA）,雌酮（E1）,17β-雌二醇（E2）,雌三醇（E3）,17α-乙炔雌二醇（EE2）和己烯雌酚（DES）,建立了快速溶剂萃取（Accelerated Solvent Extractor,ASE）,固相萃取（SPE）净化,GC-MS检测的测试方法.对比分析了不同衍生化试剂、衍生化条件对分析结果的影响,同时优化了净化步骤.通过所建立的方法对6种EDCs在污泥中的浓度进行分析,检测回收率为77.2%—118.3%,相对标准偏差小于9%.应用该方法测定了重庆某2个污水处理厂剩余污泥中的EDCs浓度.     

珠江三角洲河流饮用水源中的环境内分泌干扰物及其风险

在极低的环境暴露水平(ng·L~(-1)—μg·L~(-1)),环境内分泌干扰物(EEDs)就能对水生物的生殖、发育功能产生不利影响,甚至可能威胁到饮用水源的安全。为深入了解珠江水源水中EEDs的污染现状,采用全自动固相萃取-气相色谱/质谱联用(FASPE-GC/MS)法对珠江三角洲河流饮用水源地中EEDs的含量分布和季节变异进行了调查,并评价了其潜在的生态风险。结果发现,EEDs广泛存在于珠三角水源水中,总EEDs(ΣEEDs)的质量浓度在26.8—2 460 ng·L~(-1)之间,平均值和中值分别为775、325 ng·L~(-1);其中辛基酚(OP)、壬基酚(NP)、双酚A(BPA)和雌酮(E1)的质量浓度范围(平均值/中值)分别为LOQ (定量限)—121 ng·L~(-1)(42.9/15.2 ng·L~(-1))、15.2—2 270 ng·L~(-1)(821/338 ng·L~(-1))、1.19—177 ng·L~(-1)(56.21/52.0ng·L~(-1))、nd (未检出)—2.5 ng·L~(-1)(0.9 ng·L~(-1)/LOQ)。各水源地EEDs总体污染水平:东江东莞段流溪河下游西江北江,丰水期ΣEEDs的质量浓度显著高于枯水期(P0.05)。与国内外相关研究结果相比,珠三角河流水源水中EEDs的污染处于中高水平。丰水/枯水期水源水中OP、NP、BPA、E1的风险商(RQ)平均值分别为0.47/0.13、2.25/0.6、0.05/0.08、0.18/0.07,可见OP、BPA、E1在两季均呈中低风险水平,NP则呈中高风险水平。丰水期和枯水期饮用水源地EEDs的危害指数(HI)范围(平均值)分别为0.28—6.05(2.95)、0.045—3.23(0.88),表明丰水期的风险水平总体高于枯水期(P0.05)。两季高风险点(HI1)占总点位的41.7%,均出现在流溪河下游和东江东莞段,表明以上水源地处于高生态风险水平,已对当地水生生物及饮用水安全形成严重威胁;西江和北江的饮用水源地则处于中低风险水平。     

土壤和沉积物中有机质对双酚A和17α-乙炔基雌二醇的吸附行为

研究了土壤和沉积物原始样品bulk及其有机质组分(非水解性有机质NHC、碳黑BC和腐殖酸HA)对17α-乙炔基雌二醇(EE2)和双酚A(BPA)的吸附行为.所有的吸附等温线都很好地拟合了Freundlich模型,除HA和bulk外,所有的吸附等温线都为显著的非线性(n值为0.46—0.76).对于EE2和BPA的吸附非线性因子n值都存在这样的关系:HA>NHC>BC.EE2以有机碳归一化的Freundlich吸附能力(lgKOC)有BC>NHC>bulk>HA的关系,说明有机质成熟度越高,对EE2或者BPA的吸附能力越高.在土壤和沉积物有机质SOM(NHC、BC和HA)对吸附BPA和EE2的贡献上,NHC、BC和HA对沉积物和土壤对BPA总吸附贡献上要明显弱于它们对EE2的贡献.除了内分泌干扰物(EDCs)的疏水性影响EE2和BPA的吸附能力的差异外,分子大小和带电子苯环数也影响它们的吸附能力差异.     

北京典型灌区表层土壤与农产品酚类含量及人体健康风险评估

土壤是酚类存在的重要介质之一,土壤中残留的酚类能向作物迁移,直接关系农产品生产安全。北京市东南郊典型灌区是北京地区主要农业生产基地之一,为明确该典型灌区农产品和表层土壤酚类(壬基酚NP、辛基酚OP和双酚A-BPA)含量水平和人体健康风险,2015年利用气相色谱-质谱仪检测了该灌区20个表层土壤样品和28个作物样品中12种酚类含量,包括OP、NP1、NP2、NP3、NP4、NP5、NP6、NP7、NP8、NP9、NP10和BPA。结果显示,灌区表层土壤NP、BPA和OP质量分数分别为32.54～295.08、7.19～48.79和0.47～1.43μg·kg~(-1),采集的土壤中NP含量均未超过丹麦安全与毒理研究所提出的土壤壬基酚的限值标准(25 mg·kg~(-1))。冬小麦(Triticum aestivum L.)籽粒NP质量分数为202.19～446.16μg·kg~(-1),OP和BPA质量分数分别为3.40～25.33μg·kg~(-1)和1.36～33.27μg·kg~(-1)。夏玉米(Zea mays L.)籽粒BPA、NP和OP质量分数分别为165.59～543.67、140.39～406.47和0.77～10.83μg·kg~(-1)。果蔬OP、BPA和NP质量分数分别为11.39～204.53、93.42～893.86和220.33～392.07μg·kg~(-1),农产品BPA和NP含量均低于欧盟和丹麦安全与毒理研究所提出的相应含量限值。成人和儿童酚类非致癌指数分别为4.77×10~(-2)和1.02×10~(-1),均低于USEPA规定相应标准参考值(1.0)。总体上,北京东南郊典型灌区土壤和农产品酚类含量处于安全级别,人体健康风险也处于较低的水平。     

Occurrence of estrogenic endocrine disrupting chemicals concern in sewage plant effluent

The purpose of this study was to give a worldwide overview of the concentrations of typical estrogenic endocrine disrupting chemicals （EDCs） in the effluent of sewage plants and then compare the concentra- tion distribution of the estrogenic EDCs in ten countries based on the survey data of the estrogenic EDCs research. The concentrations of three main categories （totally eight kinds） of estrogenic EDCs including steroidal estrogens （estrone （El）, estradiol （E2）, estriol （E3） and 17a- ethynylestradiol （EE2））, phenolic compounds （nonylphe- nol （NP） and bisphenol A （BPA）） and phthalate esters （dibutyl phthalate （DBP） and dibutyl phthalate （2- ethylhexyl） phthalate （DEHP）） in the effluents of sewage plants reported in major international journals over the past decade were collected. The statistics showed that the concentration distributions of eight kinds of EDCs were in the range of ng·L^-1 to μg·L^-1. The concentrations of steroidal estrogens mainly ranged within 50.00 ng. L-1, and the median concentrations of El, E2, E3 and EE2 were 11.00, 3.68, 4.90 and 1.00 ng·L^-1, respectively. Phenolic compounds and phthalate esters were found at pg. L-1 level （some individual values were at the high level of 40.00 μg·L^-1）. The median concentrations of BPA, NP, DBP and DEHP were 0.06, 0.55, 0.07 and 0.88 μg·L^-1, respectively. The concentrations of phenolic compounds and phthalate esters in the effluents were higher than that of steroids estrogens. The analysis of the concentration in various ten countries showed that steroids estrogens, phenolic compounds and phthalate esters in sewage plant effluents were detected with high concentration in Canada, Spain and China, respectively.     

On the behaviour of the residence time at the bottom of the mixed layer

To understand why the findings of Deleersnijder et al. [(2006), Environ Fluid Mech 6: 25–42]—the residence time in the mixed layer in not necessarily zero at the pycnocline—are consistent with those of Delhez and Deleersnijder [(2006), Ocean Dyn 56:139–150]—the residence time in a control domain vanishes at the open boundaries of this control domain—, it is necessary to consider a control domain that includes part of the pycnocline, in which the eddy diffusivity is assumed to be zero. Then, depending on the behaviour of the eddy diffusivity near the bottom of the mixed layer, the residence time may be seen to exhibit a discontinuity at the interface between the mixed layer and the pycnocline. If such a discontinuity exists, the residence time is non-zero in the former and zero in the latter. This is illustrated by analytical solutions obtained under the assumption that the eddy diffusivity is constant in the mixed layer.     

刍议医院资产管理的现状及其对策

医院的固定资产和流动资产是医院赖以生存和发展的基础,是一项非经营性国有资产．目前公立医院固定资产、流动资产管理现状不容乐观,针对这种状况,首先分析问题形成的原因,然后提出管理的措施或建议,从而使资产管理工作规范化、制度化、科学化,使有限的卫生资源发挥出最大的社会效益和经济效益．参3．     

豪猪消化系统的解剖研究

为了了解豪猪的消化生理,为豪猪的人工饲养技术研究提供基础依据,以达到高效饲养豪猪的目的,笔者对豪猪的消化器官进行了系统解剖研究.结果表明:豪猪的胃为单室胃.盲肠很发达,这与其能够消化植物纤维有关.豪猪肝脏很发达,其重量为402 g,是其体重的4.59%,肝脏分叶多而明显.     

Adjusting the economy to the new energy realities of the second half of the age of oil

Our research indicates that, due to the depletion of conventional, and hence cheap, crude oil supplies (i.e. peak oil), increasing the supply of oil in the future would require exploiting lower quality resources (i.e. expensive), and thus will most likely occur only at high prices. This situation creates a system of feedbacks where economic growth, which requires more oil, would require high oil prices that will undermine that economic growth. We conclude that the economic growth of the past 40 years is unlikely to continue unless there is some remarkable change in how we manage our economy.     

Observations on the function of the glands of the foot of the pediveliger of Ostrea edulis during settlement

The use during settlement of secretions of the 9 different types of gland in the foot of the pediveliger of Ostrea edulis L. was examined experimentally. During settlement, there is a progressive decrease in the crawling speed of the larva and a strengthening of its bond with the substratum. Both changes are related to (a) a change from ciliary to muscular pedal locomotion; (b) the increasing acidity and viscosity of the mucoid secretions used; (c) the secretion of a byssus thread by the glands of the byssus duet; (d) changes in the form and composition of this byssus. At the termination of settlement, the entire contents of 2 types of gland are discharged. Their secretions give rise to the cement which permanently fixes the larva to the substratum. The 9 types of gland are utilised sequentially in a manner closely related to the 6 phases recognised in settlement behaviour.     

Mining of the forest and the time path of the price of timber

The paper analyzes the effect of transportation (site specific) costs and the effect of mining (depletion) of the forest on the time path of the price and of the net price of timber in two forestry models. The models differ in that one has zero costs and the other has positive costs. The analyses yield the standard mining theory results for certain cases. They also yield extentions of these results for cases with growth of the harvested trees and/or regeneration on the harvested land. The paper concludes, as one would expect, that the theory of the mine is useful in analyzing the time path of the price of timber.     

The impact of the Jonglei Canal on the economy of the local people

The idea of saving the water lost in the ‘Sudd’ swamp through evaporation was conceived by Egypt and Sudan for their own interests, but not for those of the Nilotic peoples living in the flood plain. Concern for the local development was only taken into consideration after the 1974 Juba riots, when three people were killed and 200 arrested. The canal has caused displacement of people from their settlements and is blocking the seasonal movement of livestock and wildlife. Conflict may arise over the use of land for grazing or irrigation. The Nilotics are concerned about the possible negative environmental impact, and the loss of their cultural identity. They maintain that Egypt should pay them monetary compensation for the disruption that the canal has caused to their livelihood.

This paper assesses the impact that the Jonglei canal project will have on the economy of the Nilotics; traces the historical development of the project; outlines the social, political and economic organization of the Nilotics; and assesses the impact the project will have on the local population. The paper concludes by casting doubt on the benefits the canal will bring to the Nilotics.     

三峡库区消落带土壤中铅污染调查

报道了三峡库区长江干流及小江支流消落带土壤中重金属铅含量背景值的调查结果。结果表明,目前土壤未被重金属铅污染。     

浅谈校园网ARP欺骗攻击与防御

ARP欺骗木马病毒是校园网络中经常出现的病毒攻击形式．基于ARP协议的概念和工作原理,并通过分析ARP欺骗的工作原理,提出了几种可行的解决ARP欺骗攻击的实用方法,以达到防范并解决ARP欺骗的目的．参5．