Distributions of dissolved organochlorine pesticides and polychlorinated biphenyls in China coastal waters

分析调查了中国部分海域海水中溶解态有机氯农药(OCPS,25种)和多氯联苯(PCbS,6种)的残留分布特征。结果表明,所有采样点都不同程度地受到了OCPS和PCbS的污染,其中福建省福州平潭和莆田湄洲岛的OCPS污染较为严重,浓度分别达到1752.59和796.19 ng/l;而辽宁省的大连老虎滩OCPS污染较轻,浓度为53.63 ng/l。各采样点海域海水中HCHS污染程度一般高于ddTS,HCHS主要以早期残留为主;根据ddT/ddTS的比值推测,在福州平潭、莆田湄洲岛和珠海淇澳岛水体显示有新的ddT输入。在各海域水体中溶解态PCbS的浓度为33.55--474.92 ng/l,均超过了美国环保局规定的海水浓度限值。因此目前我国沿海海域水体中持久性有机污染物有机氯农药和多氯联苯污染仍不能忽视。The concentrations of organochlorine pesticides(OCPs,25) and polychlorinated biphenyls(PCBs,6) in seawater collected from China coast were investigated.The results showed that concentrations of OCPs ranged from 53.63 to 1752.59 ng/L in seawater,and the highest value was in Pingtan(Fuzhou) while the lowest value was in Laohutan(Dalian,Liaoling province).At all of sampling sites,the concentrations of DDTs and HCHs were lower than the limits of national seawater quality standards(class 1),and the concentration of HCHs was higher than that of DDTs.The ratios of DDT/DDTs showed new DDT into Pingtan(Fuzhou),Meizhoudao(Putian) and Qi'aodao(Zhuhai,Guangdong Province),whereas the isomers characteristics for HCHs showed the residues at all sampling sites.The concentrations of dissolved PCBs ranged from 33.55 to 474.92 ng/L in seawater,which were higher than the limit of EPA seawater quality standard.However,the occurrence of OCPs and PCBs in seawater along China coast should be concerned.国家自然科学基金(40476048;20777060);厦门大学新世纪优秀人才计划基

利用DZ原料研制高温窑具涂料

利用锆英石经等离子处理而得的DZ原料,研制出一种由ZrO_2、SiO_2和莫来石晶体组成的DZ涂料,用作窑具的保护层。由于这种涂料具有高温晶相稳定,导热系数较大,热膨胀系数较小,抗热震性强等优点,对提高窑具的使用寿命取得了显著的效果

Applying fish biomarkers and IBRv2 for monitoring and assessing biological effects of petroleum hydrocarbon pollution in Quanzhou Bay

以褐菖鲉(Sebastiscus marmoratus)细胞色素P4501A四种生物标志物,即鳃丝EROD活性、肝EROD活性、肝CYP1A mRNA和肝CYP1A蛋白为指标,在泉州湾海域选择6个站位(包括1个对照站位),开展了为期两周的野外监测实验,研究了上述生物标志物的变化特征以及它们同表层海水中石油类含量和沉积物物中16种优先监控的PAHs含量之间的相关性,并利用新一代综合生物标志物响应指数法(IBRv2)对监测站位石油类和PAHs污染效应进行了评价.结果显示,不同站位的上述四种生物标志物变化趋势基本一致;生物标志物的变化与相应站位表层水中石油类含量及沉积物中PAHs总含量相吻合;IBRv2分析结果表明,各监测站位IBRv2指数介于1.5~4.2之间,其中2号站环境污染压力最大,4号站最小.在复杂的海洋污染条件下,采用CYP1A多种生物标志物监测技术能够更加全面反映石油类等污染及其生物效应状况.In the present study,rock fish Sebastiscus marmoratus was chosen as a sentinel animal,and cytochrome P4501A( CYP1A) biomarkers,namely gill filament and hepatic EROD activities,CYP1 A mRNA and its protein expressions were used as biomarkers to monitor the biological effects of petroleum hydrocarbon pollution in Quanzhou Bay,Fujian Province. The field monitoring experiment was conducted for 2 weeks in 6 sites including a reference site. The expression patterns of the CYP1 A biomarkers and the correlation of the biomarkers with the contents of petroleum hydrocarbons in the surface water and polycyclic aromatic hydrocarbons( PAHs) in sediment were studied,respectively. Moreover,a novel method for ecological risk assessment named "Integrated Biological Responses version 2( IBRv2) "was used to assess the pollution stress on the S. marmoratus. Compared to the fish caged in the reference site,the gill filament and hepatic EROD activities,CYP1 A mRNA and its protein expressions were significantly elevated in fish from the sites with much polluted of petroleum hydrocarbons and PAHs,especially with high molecular weight PAHs. The IBRv2 index of 6 sites varied from 1. 5 to 4. 2,and the site 2 had the highest environmental stress while the site 4 had the lowest. The present results show that the integrated biomarker of CYP1 A of S. marmoratus is a good approach for monitoring and assessing the biological effects of petroleum hydrocarbon pollution in coastal marine environment.海洋公益性行业科研专项经费资助项目(201005016);; 国家自然科学基金资助项目(41206107);; 国家海洋局青年海洋科学基金重点资助项目(2013108);国家海洋局海洋溢油鉴别与损害评估技术重点实验室资助项目(201315

Effect of Temperature on the Self-Humidifying Open-Cathode Proton Exchange Membrane Fuel Cell

温度对自增湿阴极开放式质子交换膜燃料电池（PEMFC）的性能有着重要的影响. 依据自制的常压自增湿型PEMFC及温度控制设备搭建测试平台，测试了燃料电池在不同工作温度下的输出特性曲线—伏安曲线和功率输出曲线. 通过拟合得到了电极过程动力学参数，分析了工作温度影响电池性能的主要原因.Based on the experiments about the output characteristics of a home-made temperature-controlled PEMFC system with atmospheric pressure and no external humidifying condition in different loading voltages and operating temperatures, the optimum operating temperature at different loading voltages can be obtained by tracking the output characteristics of PEMFC operating over a range of temperatures. By analyzing the fitted data the kinetic parameters are evaluated and the effect of different operating temperatures on the PEMFC performance is discussed from a view of electrode kinetics.作者联系地址：1. 西南交通大学电气工程学院，四川 成都 610031；2. 西南交通大学机械工程学院，四川 成都 610031；3. 重庆理工大学机械工程学院，重庆 400054；4. 淡马锡理工学院清洁能源研究中心，新加坡 529757Author's Address: 1. School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031, China; 2. School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; 3. College of Mechanical Engineering, Chongqing University of Technology, Chongqing 400054, China; 4. Clean Energy Research Center, Temasek Polytechnic, 529757, Singapore通讯作者E-mail：[email protected]

搜寻第二个地球——系外地球(ET)巡天计划

系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2点晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜构成的空间天文台, 结合凌星法和微引力透镜法, 利用空间超大视场和超高精度的光学测光观测, 首次发现富有重要意义、被广泛关注的系外地球, 并确定其发生率, 对目前了解甚少的类地行星和流浪行星进行国际上第一次大规模的种群普查, 首次发现流浪地球, 并确定其发生率, 揭示类地行星和流浪行星起源, 为地外生命探寻提供候选者和新方向. ET卫星的观测结果、统计研究以及和对理论的检验将回答系外地球在宇宙中有多普遍, 类地行星是如何形成和演化的, 流浪行星又是如何起源的这些亟待解决的前沿科学问题. 对ET卫星发现的系外地球样本的后随观测, 将精确测量其质量、密度和大气成分, 有助于深入分析宜居性特征. 此外, 对ET新发现的大量各种系外行星样本的研究, 以及对理论的检验将推动这些种类的行星形成和演化规律的更深入认识, ET的大量高精度、高频次和长基线测光数据将推动星震学、银河系考古学、时域天文学、双星和双星黑洞等领域的研究

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel