The geochemistry of iodine and 129I dating in marine sediments and ferromanganese crusts

地表环境中碘分布主要受海洋系统，特别是海洋沉积圈控制。了解海洋沉积物碘的地球化学，对人类和生态环境健康、氧化还原环境变化等研究具有重要意义。碘的最长寿命放射性同位素129I具有天然和人工两种来源。天然129I可用来进行时间尺度达80Ma测年对象的定年。目前天然129I主要用来进行地热流体和油田卤水等年龄的测定，尚未见到海洋铁锰结壳129I年代学和碘研究的报道。 本文研究了不同海域（太平洋、东海、胶州湾和福建潮间带）沉积物和铁锰结壳（太平洋）碘含量及其分布，探讨了碘与有机物、矿物组成、粒径和210Pb 的关系，讨论了磷酸盐化对结壳碘分布的影响。加速器质谱法测定了铁锰结壳129I/127I比值...The global iodine distribution is dominated by the marine system specially the ocean sediments. Understanding of geochemistry of iodine in the marine sediments is of great significance for the health of environment and human and variation of redox environment. 129I which is the longest half-life radioisotopes of iodine has two sources of cosmogenic and anthropogenic. Cosmogenic 129I can be used fo...学位：理学博士院系专业：海洋与环境学院_海洋化学学号：2242008015010

Vertical mixing rate evaluation based on radium isotope distributions of Yellow Sea and East China Sea

在黄海和东海采样测定了水体中的镭同位素分布,用平流扩散模型描述镭同位素分布,最小二乘方法计算了垂直涡动扩散系数和上升流或下降流流速.结果给出北黄海中部、南黄海中部、浙江沿岸和台湾北部海域存在上升流,流速分别为0.46x10--(-3)CM·S--(-1)、0.17x10--(-3)~1.39x10--(-3)CM·S--(-1)、2.02x10--(-3)~3.04x10--(-3)CM·S--(-1)和1.06x10--(-3)~2.51x10--(-3)CM·S--(-1).北黄海中部和东海东北部存在下降流.流速分别为-2.30x10--(-3)CM·S--(-1)和-0.61x10--(-3)~-2.10x10--(-3)CM·S--(-1) .计算同时给出的垂直涡动扩散系数为5.84~48.2 CM--2·S--(-1),平均值为22.3 CM--2·S--(-1).北黄海和浙江沿岸上升流流速与文献的结果一致;北黄海中部存在下降流与文献的结论一致.本研究结果与文献结果一致是对所建立的方法的肯定,也是对文献研究结果的支持.Radium isotopes in the seawater of the Yellow Sea and the East China Sea (YSECS) were measured and their vertical distributions were described using an advection-diffusion model.Vertical eddy diffusion coefficients and advection velocities in the YSECS were calculated by fitting the distributions of radium isotopes in the seawater using least-square method.Results showed that upwellings occur in the middle of Northern and Southern Yellow Sea,coastal zone of Zhejiang,and Northeast of Taiwan.The current rates of upwellings are 0.46×10--(-3)cm·s--(-1), 0.17×10--(-3)～1.39×10--(-3)cm·s--(-1),2.02×10--(-3)～3.04×10--(-3)cm·s--(-1) and 1.06×10--(-3)～2.51× 10--(-3)cm·s--(-1) for above four sea areas respectively.Downwellings are indicated in the middle of Northern Yellow Sea and Northeastern East China Sea and the current rates are -2.30×10--(-3)cm·s--(-1) and -0.61×10--(-3)～-2.10×10--(-3)cm·s--(-1) respectively.The vertical eddy diffusion coefficients were obtained as 5.84～48.2 cm--2·s--(-1) with an average of 22.3 cm--2·s--(-1) from the same calculation.Upwelling velocity of Northern Yellow Sea and coastal zone of Zhejiang given by this study is in agreement with the results of literatures,and downwelling in Northern Yellow Sea is also supported by the literature.The agreement of the results obtained in this study with that of literatures not only confirms previous inference about upwelling distribution in the Yellow Sea and East China Sea,but also affirms the validity of our method.973计划项目(2005CB422305;2006CB400602)资

White LED Phosphor Performance Tested by Spectro320e Spectrometer

我国lEd产业发展非常迅速,稀土钇铝石榴石(yAg)系列荧光粉广泛应用于白光lEd。德国InSTruMEnT SySTEMS公司的SPECTrO320E光谱仪适合光谱的精确测量,文章结合SPECTrO320E和远方公司的PE-5荧光粉激发装置,实现蓝光激发下黄色yAg荧光粉的色品坐标、相对亮度、量子效率等参数精确的测试,研究了仪器在不同的测试条件如暗电流、光电倍增管、密度滤光片等设置的不同,对测试结果的影响,并给出利用本装置测试荧光粉时应该注意的事项。LED industry in china develops rapidly.Yttrium aluminitum garnet(YAG) phosphors are widely applied in white LEDs.The Instrument Systems company's Spectro320e spectrometer is suitable for accurate measurement of the spectrum.It is combined in this paper with the Everfine company's PE-5 phosphor excitation device to achieve the accurate testing of yellow YAG phosphors excited by blue light,such as chromaticity coordinates,relative brightness and quantum efficiency.We also studied the influence of different testing conditions on the results,such as dark current,PMT and density filter.The cautions are provided herewhen using the Spectro320e spectrometer

ST段抬高型急性心肌梗死院前溶栓治疗中国专家共识

急性心肌梗死仍然严重威胁我国人民健康,在我国广大城乡地区,形势更为严峻[1,2]。及时救治急性心肌梗死患者,降低死亡率和保护心脏功能刻不容缓。鉴于我国的实际情况,院前溶栓治疗在大城市以外的城乡地区具有重要意义。为此,中国医师协会胸痛专业委员会及中国医学救援协会心血管急救分会专门组织有关专家制订了本共识,旨在帮助院前医疗急救人员对急性心肌梗死患者选择最佳

Application process of --(129)I in marine radiochronology

应用129I的海洋学研究可分为3个方面:(1)人工129I的年代学,利用人工放射性在沉积物岩心中的记录,包括以核试验全球最大沉降年1963年为参考时间和利用切尔诺贝利核电站事故发生的1986年作为参考时间的年代测定.(2)利用宇生129I的年代学,测年体系主要有地热流体、天然气水合物和石油地质体系.(3)利用核燃料后处理厂排放的129I进行的海洋环流与混合研究.核试验和核事故释放的129I测定的是现代沉积物年代,测年时间尺度为50A.人们提出人类利用原子能之前地球表层初始129I丰度为1.5x10-12,并以该值作为利用宇生129I估算年代的初始丰度值.半衰期和丰度探测下限水平允许宇生129I可测年的时间尺度为80MA.本文综述了以上几方面的研究进展.海洋多金属结核和结壳的生长速率为毫米每兆年量级,一块1~10CM大小的多金属结核和结壳所能涵盖的时间尺度约为10~100MA,刚好是129I测年的时间尺度,所以本文提出了多金属结核和结壳可能是合适的129I测年介质的观点.Application of 129I in oceanography include:(1) dating by 129I released from nuclear test and accident recorded in sediment core,in which peaks related with maximum atmospheric deposition of anthropogenic radioactivity released during nuclear test was in 1963 and Chernobyl Nuclear Power plant accident happened in 1986;(2) dating using cosmogenic 129I,the dating system are at present geothermal fluid,gas hydrate and oil information;(3) marine circulation and mixing traced by 129I discharged from nuclear fuel reprocessing plants.The modern sediment was dated by anthropogenic 129I in the time scale of 50a.Without anthropogenic radioactivity,the initial 129I abundance of surface reservoir of earth is confirmed as 1.5×10-12 that can be used as starting value for calculation of cosmogenic 129I dating.The half-life and detection limit of abundance allows cosmogenic 129I dating within range of 80Ma.This paper summarize above developments of 129I dating.The growth rate of Polymetallic nodule and crust is about mm/Ma,and time scales of a piece of 1～10cm the size of the polymetallic nodules and crusts can cover about 10～100Ma,so we thought that the polymetallic nodule and crust may be the best mediums for 129I dating.国家自然科学基金资助项目(40036010

The distributions of radionuclides in a sediment core and sedimentary rate in the intertidal zone of Xinghuawan Bay

利用2007年8月31日采集于福建兴化湾西岸的潮间带沉积物岩心样品,用γ谱方法测量了其放射性核素含量,对岩心中核素的分布及其成因进行了讨论,估算了研究区沉积物的沉积速率,探讨了沉积物的物源,结果表明:(1)238u2、28TH2、28rA2、26rA2、10Pb1、37CS和40k的含量分别为35.0--60.6、52.6--69.3、49.0--66.5、22.7--36.2、26.3--84.8、0.5--1.3和775--831 bQ/kg;(2)用238u2、26rA1、37CS和40k作为示踪剂进行物源分析发现,兴化湾潮间带沉积物主要源于邻近的福州和莆田地区的土壤,所占比率分别为54%和46%;(3)用210PbEX和137CS方法估算得兴化湾西岸潮间带沉积物的平均沉积速率分别为0.38 CM/A和0.36 CM/A。岩心中210PbEX分布表明,自20世纪末,研究区潮间带沉积速率加快。One sediment core was collected from intertidal zone located west coast of Xinghuawan Bay,Fujian,China.The radionuclide contents in the cores were measured by γ spectrometry and the vertical distributions of the nuclides were discussed.The sources of sediment were evaluated using 238U,226Ra,137Cs and 40K as tracers.The sedimentary rate was estimated by 210Pbex and 137Cs methods.The detectable nuclides in this core are 238U,228Th,228Ra,226Ra,210Pb,137Cs and 40K.The contents of these nuclides are 35.0--60.6,52.6--69.3,49.0--66.5,22.7--36.2,26.3--84.8,0.5--1.3 and 775--831 Bq/kg,and with the averages of 45.4,61.2,61.2,31.4,45.6,0.9 and 804 Bq/kg respectively.The 238U activities in the 0--40 cm zone were comparable within the measuring error and high 238U contents were found in the depth of 50～60 cm and below which 238U activities fluctuate with no trend.With the similar trend,from surface to 22 cm depth the activities of 228Th and 228Ra are lower and increase slowly with increasing depth,and they are consistent within the error.Throughout the entire core length the 228Ra and 228Th is decay equilibrium.226Ra activities increase with increasing depth from surface to 22 cm depth,and the contents comparable from 22 cm to 72 cm,occurring fluctuation deeper than 72 cm.The 210Pb activities decrease exponentially both from surface to 12 cm and in the zone of 16～40 cm,but below the depth of 40 cm 210Pb is decay equilibrium with 26Ra.The distribution has a maximum activity at the depth of 16 cm,above which the 137Cs contents are consistent within measuring error but below which decrease with depth.40K is uniform distribution through entire length of the core.The sedimentation sources of Xinghuawan Bay are mainly from the surface soil of Fuzhou and Putian Prefectures surrounding it.Using 238U,226Ra,137Cs and 40K as tracer,by the content data of these four nuclides in the sediments measured in this study and in the land soil reported by literature,we calculated the contributions of the soils of Fuzhou and Putian Prefecture are 54% and 46% respectively.That means that natural radionuclides can be used as tracers to analyse material source of sediment.Sedimentation rate based on 210Pbex and 137Cs was estimated,that was 0.38 cm/a and 0.36 cm/a.From the 210Pbex distribution,we can deduce the sedimentation rate had changed at about 2000.The sedimentation rate was 0.27cm/a before 2000 and 1.07cm/a after that time,which was considered as abundant terrigenous material supplied by human activities after 2000.国家自然科学基金资助项目(40306018

Iodine Study of Marine Sediments from Four Sea Areas

分大洋、边缘海、海湾和潮间带四种海区,测定了采集自东太平洋、东海、山东胶州湾的海洋沉积物岩心和采集自福建兴化湾、九龙江河口、东山湾3个海湾潮间带沉积物岩芯的碘含量,研究了岩芯中碘的分布特征,探讨了碘与有机物的相关关系。结果给出:东太平洋岩芯碘含量为68.2~105.6 Mg/kg,东海岩芯碘含量为35.2~77.8 Mg/kg,胶州湾海洋和周边陆地沉积物碘含量分别为51.6~94.3和36.5~50.3 Mg/kg,福建兴化湾、九龙江河口和东山湾3个海湾潮间带沉积物岩芯的碘含量分别为2.5~43.7、17.3~39.6和11.3~29.1 Mg/kg。不同海区沉积物的碘含量水平从高到低依次为:东太平洋>胶州湾>东海>胶州湾周边陆地沉积物>福建3个海湾潮间带沉积物。东太平洋沉积物岩芯,以及兴化湾和东山湾潮间带岩芯碘与有机碳含量呈正相关关系,其余海区沉积物中的碘与有机碳的含量相关性不明显。For four kinds of sea areas,the iodine in sediment cores were measured,the cores are marine sediment cores collected from East Pacific,East China Sea and Jiaozhou Bay,and intertidal sediment cores from Xinhua Bay,Jiulongjiang Estuary and Dongshan Bay of Fujian Province,China.The iodine distribution features in sediment cores were studied and the correlations between iodine and organic carbon in the sediments were evaluated.The results gave that the iodine contents vary from 68.2-105.6 mg/kg in the core from East Pacific and they are between 35.2-77.8 mg/kg in the core from East Chins Sea.The iodine contents are in the range of 51.6-94.3mg/kg and 36.5-50.3 mg/kg for the marine sediments of Jiaozhou Bay and sediment from the land surrounding Jiaozhou Bay respectively.They are 2.5-43.7 mg/kg,17.3-39.6 mg/kg,and 11.3-29.1 mg/kg for the intertidal sediment cores from Xinhua Bay,Jiulongjiang Estuary and Dongshan Bay respectively.Sequentially,from high to low level of iodine content is East Pacific > Jiaozhou Bay > East China Sea > marine sediment of Jiaozhou Bay >land sediment surrounding Jiaozhou Bay > intertidal sediments from three bays of Fujian Province.The correlations between iodine and organic carbon content in the sediment from East Pacific,Xinhua Bay and Dongshan Bay are well close,in contrast with that,they are not found for the sediments from other sea areas.国家自然科学基金项目“应用I-129的海洋铁锰结壳年代学”(编号:41073044)资

The determination of iodine in the sediment cores from the intertidal zone of the Xinhua Bay,the Jiulong Estuary and the Dongshan Bay

用碱熔法处理样品,水沥取,用分光光度法测量了采集自福建省兴化湾、九龙江河口和东山湾3个海湾潮间带沉积物岩心的碘分布。兴化湾、九龙江河口和东山湾3岩心中的碘含量分别为2.5~43.7,17.3~39.6和11.3~29.1Mg/kg。3个沉积物岩心中的碘含量稍高于福建省的土壤的碘含量,与我国海域的沉积物碘含量在同一水平,但明显低于文献报道的开阔海域沉积物的碘含量。兴化湾和东山湾沉积物中的碘与有机碳含量有较好的相关性;在九龙江河口采集的岩心中的碘与有机物碳含量的相关性较差。推测海洋源的沉积物碘与有机碳含量相关性较好,而陆源沉积物的碘与有机碳含量相关性较差。Three sediment cores are collected from the intertidal zone of the Xinhua Bay,the Jiulong Estuary and the Dongshan Bay of Fujian Province,southeastern China.The iodine contents in the sediment samples sliced by the three cores are measured by a spectrophotometric method after alkali fusion and leached with water.The results show that the iodine contents are between 2.5and 43.7mg/kg in the core from the Xinhua Bay,and 17.3and 39.6mg/kg in that from the Jiulong Estuary and 11.3and 29.1mg/kg in that from the Dongshan Bay respectively.The iodine contents in sediment samples of this study are higher than that of China's soils and at same level with those of China's Seas sediment.The iodine contents are well correlated with the organic carbon content in the sediments from the Xinhua Bay and the Dongshan Bay,respectively,where matter may mainly from the ocean.The correlation between iodine and organic carbon content is not well close in the sediments from the Jiulong Estuary,where the material is mainly terrigenous.It is shown that the correlation between iodine and organic carbon contents in the sediments from the ocean is well,but not close in that terrigenous fraction.国家自然科学基金资助项目“应用129I的海洋铁锰结壳年代学”(41073044

Measuring thermal resistance for high voltage LED device and module by applying external voltage source

热阻是衡量lEd器件/模块散热性能的重要参数。针对大电压lEd器件/模块,实验采用T3STEr/TErAlEd热光参数测试仪,利用外部电压源供电方法,实现了对超过仪器量程的大电压lEd器件的热阻测试。该方法拓展了热阻测试仪的常规测量范围,使正向电压大于15V的lEd器件/模块的热阻测试成为可能。Thermal resistance is a key parameter for evaluating thermal performance of LED device/module.Reliable measurement of thermal resistance becomes extremely important.Aiming at that the high voltage LED device/module has been applied popularly in lighting,an improved thermal resistance measurement method for LED device/module with forward voltage larger than 15Vis achieved by applying external voltage source to the T3Ster/Teraled.The result shows that the external voltage source method can effectively expand the testing range of thermal resistance tester.福建省重大科技项目(2011H6025); 国家自然科学基金项目(11104230