Regional fractures and denudation of gold ore deposits in Gangdise block,Tibet: Evidence of Ag/Au values     

Li  Shengrong  Deng  Jun  Hou  Zengqian  Xiao  Run  Yuan  Wanming  Feng  Xiaoliang  Zhao  Zhidan  Shen  Junfeng  Zhou  Su 《中国科学:地球科学(英文版)》2001,44(1):121-127

Mapping with Ag/Au ratios of mineralized rocks and ores as a parameter reveals that the deep fractures in the Gangdise block control the distribution of the high value regions which may represent the shallow zones of strongly mineralized areas. The variance gradient regions with large Ag/Au ratio may represent the boundaries between strongly mineralized areas and weakly mineralized areas. In the middle part of the Gangdise block, gold and silver mineralization centers mainly distribute along the NW extending Coqen-Xigaze region, NE extending Yangbajain region and E-W extending Lhasa-Gongbogyamda region. The gold and silver mineralized rocks and ores may have been slightly denuded in the west of the middle Gangdise block, and the denudation in the east, however, may be stronger. The primary gold and silver prospect in the west may be better than in the east.

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Microbial modulation in the biomass and toxin production of a red-tide causing alga   总被引：6，自引：0，他引：6  

Zheng TL  Su JQ  Maskaoui K  Yu ZM  Hu Z  Xu JS  Hong HS 《Marine pollution bulletin》2005,51(8-12):1018-1025

The effect of S₁₀, a strain of marine bacteria isolated from sediment in the Western Xiamen Sea, on the growth and paralytic shellfish poison (PSP) production in the alga Alexandrium tamarense (A. tamarense) was studied under controlled experimental conditions. The results of these experiments have shown that the growth of A. tamarense is obviously inhibited by S₁₀ at high concentrations, however no evident effect on its growth was observed at low concentrations. Its PSP production was also inhibited by S₁₀ at different concentrations, especially at low concentrations. The toxicity of this strain of A. tamarense is about (0.95–12.14) × 10⁻⁶ MU/cell, a peak toxicity value of 12.14 × 10⁻⁶ MU/cell appeared on the 14th day, after which levels decreased gradually. The alga grew well in conditions of pH 6–8 and salinities of 20–34‰. The toxicity of the alga varied markedly at different pH and salinity levels. Toxicity decreased as pH increased, while it increased with salinity and reached a peak value at a salinity of 30‰, after which it declined gradually. S₁₀ at a concentration of 1.02 × 10⁹ cells/ml inhibited growth and the PSP production of A. tamarense at different pH and salinity levels. S₁₀ had the strongest inhibitory function on the growth of A. tamarense under conditions of pH 7 and a salinity of 34‰. The best inhibitory effect on PSP production by A. tamarense was at pH 7, this inhibitory effect on PSP production did not relate to salinity. Interactions between marine bacteria and A. tamarense were also investigated using the flow cytometer technique (FCM) as well as direct microscope counting. S₁₀ was identified as being a member of the genus Bacillus, the difference in 16S rDNA between S₁₀ and Bacillus halmapalus was only 2%. The mechanism involved in the inhibition of growth and PSP production of A. tamarense by this strain of marine bacteria, and the prospect of using it and other marine bacteria in the bio-control of red-tides was discussed.  相似文献   

A Correlation between Proton Events and Hα Flares and its Possible Interpretation     

Kim Jik Su  Yuan-Yong Deng  Kim Kum Sok  Kim Jin Song National Astronomical Observatories  Chinese Academy of Sciences  Beijing Pyongyang Astronomical Observatory  Academy of Sciences  DPR of Korea 《中国天文和天体物理学报》2001,(6)

1 INTRoDUCTIONIt is well known that solar proton flares are maiuly correlated with strong, bright H. flares,in particular, with two ribbon flares. Ellison et al. (l961) were the first to draw attelltion tothe faCt that all cosndc-ray flares had the typical two-ribbon shape. Then, Svestka and Simon(1976) drew uP the "Catalog of Solar Particle Evellts, 195ty1969", and using this Catalog,Dodson and Hedeman could safely identify the flare sources for 50 proton events. Out of the 50idellti…  相似文献   

关注"数字地球"     

欧阳飚  苏小兰 《国际地震动态》2000,(11):18-19

受人事部委托,中国地震局人事教育司于2000年7月10～14日在北京举办了"百千万人才工程"数字地球"高级研讨班.高研班聘请了陈运泰院士、陈述彭院士、马宗晋院士等8位国内著名"数字地球"专家做讲座;28位学员分别来自全国各地18个单位,他们主要是省部级"百千万人才工程"人选,以及对"数字地球"有一定研究基础的优秀青年科技骨干.  相似文献   

桂林市气象网络语音监控系统   总被引：3，自引：1，他引：3  

纪英唐伍斌  张雅昕苏娟 《广西气象》2005,26(2):44-46

介绍了《桂林市气象网络语音监控系统》五大模块的主要功能和某些模块在编程中遇到的技术难题以及解决的办法。  相似文献   

新疆及周边地区Lg尾波的Qem值分布   总被引：2，自引：0，他引：2       下载免费PDF全文

徐彦  毛燕  胡家富  苏有锦  丛连理 《地震学报》2005,27(2):155-162

首先运用叠加谱比法， 对新疆地区22个数字化台网台站、乌鲁木齐台站以及周边的7个台站1999～2003年上半年所记录的1 156个宽带垂直记录，进行了处理， 得到了与各射线相对应的Q0值（1 Hz处的Q值）和频率相关因子eta;. 在此基础上， 应用反投影技术， 得到了新疆地区1deg;times;1deg;网格的Q0值和eta;值的分布图象. 结果表明: 在塔里木地台及西伯利亚地台边缘，Q0值较高，为300～450； 而在南部的西昆仑褶皱系、松潘甘孜褶皱系，Q0呈现出低值，在150～250的范围内变化；在北部的准葛尔褶皱系和天山褶皱系，Q0现出较低的值，在250～300的范围内变化，eta;值的变化范围为0.5～0.9.    相似文献   

内标和快速共沉淀-火焰原子吸收光谱法测定食盐中的镉   总被引：3，自引：0，他引：3  

苏耀东  秦立俊李静 陈龙武 《岩矿测试》2005,24(3):201-204

探讨了用火焰原子吸收法测定以（2-吡啶偶氮）-2-萘酚-Ni（Ⅱ）为共沉淀体系，以Mn（Ⅱ）为内标，在pH=9．0的条件下快速共沉淀分离富集食盐中的痕量Cd。当试液为100mL时，方法的检出限为5．7μg/L，加标回收率为96％～101％，相对标准偏差（RSD，n=6）〈5％，基本消除了基体干扰。  相似文献   

地勘单位企业改制存在的问题及对策     

苏铁军 《中国煤田地质》2005,17(2):62-65

地勘单位企业进行股份制改造，建立现代产权制度，是地勘单位企业的发展方向，但由于诸多原因造成改制中国有资产大量流失与分配不公在分析了地勘单似企业改制中存在的主要问题及具体表现的丛础上，提出了相应的对策，对规范和加强地勘单位改制工作具有现实意义。  相似文献   

气象专业服务自动决策播音系统   总被引：1，自引：0，他引：1  

徐良谋  蔡士来  闵莉  潘新民  李平  仓粟 《气象》2000,26(7):36-39

气象专业服务自动决策播音系统具有对各类专业服务产品编辑制作功能;可根据不同天气型搜索服务决策建议库进行自动决策;动用声控技术实用现了计算机对天气警报对讲发射机的直接控制和自动播音;该系统具有任务自动叫醒功能。该播音系统采用ＶＣ＋＋５．０编程,界面美面,操作简便。  相似文献   

燕山渤海地震带两端地震活动的特征     

苏鸾声 《地震研究》2000,23(3):314-317

研究了燕山渤海地震带两端京西北及晋冀蒙交界地区和渤海海峡及邻区的地震活动特征,得出它们具有：同期活跃、间歇发震、强弱交替、西北早和东南晚的特点。分析认为,渤海海峡及邻区在２０００年前后存在发生５～６级中强地震的可能性。  相似文献