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1.
通过对华东地区21个铀矿区内居民居住环境大气中氡与其子体α潜能浓度的调查,居民居室外氡浓度均值范围为6.73~132.Bq/m^3,氡子体α潜能浓度均值范围为11.0~78.8hJ/m^3。居室内的平均氡浓度范围为14.5~185.8Bq/m^3,氡子体α潜能浓度均值范围为13.8~104.2nJ/m^3;对居民饮用水源的取样分析表明,铀的均值范围为0.12~1.68μg/L,钍的均值范围为0.02~0.42μg/L,镭--226的均值范围为0.90~12.1mBq/L,与全国和当地的放射性天然本底水平比较接近,均属正常本底水平。  相似文献   

2.
对金山金矿田的金山金矿,花桥金矿区露天水源天然铀,氡,居民区和井下作业人员γ外照射有效剂量等进行调查的结果表明,金山,西蒋矿区露天水源天然铀,氡浓度均小于限值0.05mg/L和37.00Bq/L空气氡浓度为0.008~0.013Bq/L。居民和井下作业人员γ外照射年有效剂量均小于1ms和5ms,矿区放射性均在国家规定的环境评价指标限制之内,对矿山的人身和环境无影响。  相似文献   

3.
在居民所受到的天然辐射作用的总剂量中,氡及其子体的吸入占有主要部分。在进行综合生态测量时,在俄罗斯的不同地区进行了氡及其子体的测量;这些地区是:圣彼得堡地区、俄中部地区和阿尔泰地区。使用了以径迹蚀刻和活性炭探测器为基础的剂量计,对环境氡浓度进行了测量;这是两种适用的低成本方法。以0.5的平衡系数和推荐的0.061mSv/(Bq/m^3)有效测量当量系数计算了氡子体活度和有效剂量当量。在21个村镇对  相似文献   

4.
矿石中稀土总量快速分离法的改进   总被引:4,自引:0,他引:4  
范福南 《岩矿测试》2000,19(3):217-220
半微量量取样,碱熔,掩蔽剂提取,用20g/L Na2CO3-1g/L水杨酸钠混合洗涤济洗除在稀土沉淀中的铀和钍,分取制得的试液用偶氮胂III光度法测定稀土总量。可测范围的质量分数(W/10^-2)为0.01~12.00,准确度与PMBP-苯萃取法所得结果相符,精度度(RSD,n=12)为2.8%。  相似文献   

5.
桂、湘某些岩溶洞穴氡及其子体分布特征的初步研究   总被引:8,自引:3,他引:5  
李彬  林玉石  徐胜友 《中国岩溶》1995,14(4):345-351
通过对广西、湖南4个洞穴空气中的氧及其子体的初步研究发现,桂林地区的洞穴氧含量与世界上其它一些洞穴相比普遍较低,仅为0.046~0.168wL(或339~620Bq/m ̄3),而世界上洞穴最高浓度达41.97WL。这可能与桂林地区碳酸盐岩地层中的低背景值有关。同时发现,洞穴内空气流动程度是决定洞内氧及其子体聚集量的主要因素。在同一洞穴中,洞口附近的氧浓度要比深部低;而在放射性元素高背景区的万华岩中,由于它为一地下河型洞穴,且有三个进出口,洞内空气流动程度较高,故氧的浓度反而很低,仅为78~88Bq/m ̄3(0.011~0.012WL)。   相似文献   

6.
在H3PO4介质中,微量Pd(Ⅱ)能阻抑二安替比林对溴苯基甲烷(DApBM)与V(Ⅴ)的显色反应,阻抑程度与Pd(Ⅱ)量呈线性相关。据此建立了测定微量Pd(Ⅱ)的新方法。方法检测限为56.0μg/L,测定范围为0.0~480.0μg/LPd(Ⅱ)。阻抑反应的表观活化能为86.72kJ/mol,表观速率常数为5.57×10-4/s,反应终止后至少稳定24h。试样的加标回收率为91.7%~101%(n=4)。该法用于w(Pd)在10-3水平的冶金产品和催化剂中钯的测定,结果与原子吸收法测定结果相符,RSD(n=6)在2.8%~3.3%。  相似文献   

7.
加拿大卫生福利部希望对全加拿大本国人住宅中的氡的潜在危害进行评价。根据航空伽玛测量数据。地质和地球化学,选择了41个潜在氡高的居民区的16个潜在氡低的居民区进行取样,在潜在氡低的居民区中没有一个住宅氡的水平超过400Bq/m^3,而在潜在氡高的居民区中很多住宅超过加拿大的标准800Bq/m^3。根据这一研究结果,加拿大卫生和福利部开始了一项追踪计划,测量住宅中氡浓度可能超过加拿大标准800Bq/m  相似文献   

8.
研究了在Tween80存在下,2,4-二甲氧基苯基荧光酮与铜的配合物的荧光熄灭体系,在pH为8.0 ̄8.8的Na2CO3-H3BO3+KCl缓冲介质中,在λex=400nm,λem=510nm其体系产生的荧光熄灭程度最大。铜的线性范围为0 ̄20μg/L。方法的检测限为0.72μg/L。  相似文献   

9.
流动注射—催化光度法测定痕量锰   总被引:3,自引:0,他引:3  
吴丽  朱化雨 《岩矿测试》1996,15(2):120-123
在非离子表面活性剂吐温-80存在的H3PO4介质中,Mn^2+对V(V)氧化二安替比林苯乙烯甲烷(DAVPM)成红色化合物的反应具有较强的催化作用,基于此采用流动注射-催化光度法测定了痕量Mn^2+,该方法的检测波长为555nm,检出限为0.02μg/L Mn,线性范围为0.02 ̄6μg/L Mn,进样频率为60次/h,对5μg/L Mn进行10次测定的相对标准偏差为1.8%。经环境标准样品分析验  相似文献   

10.
流动注射-催化光度法测定痕量锰   总被引:5,自引:0,他引:5  
在非离子表面活性剂吐温-80存在的H3PO4介质中,Mn2+对V(V)氧化二安替比林苯乙烯甲烷(DAVPM)成红色化合物的反应具有较强的催化作用,基于此采用流动注射-催化光度法测定了痕量Mn2+,该方法的检测波长为555nm,检出限为0.02μg/LMn,线性范围为0.02~6μg/LMn,进样频率为60次/h对5μg/LMn进行10次测定的相对标准偏差为1.8%。经环境标准样品分析验证方法可行并已用于水样中痕量Mn2+的测定。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

18.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of  相似文献   

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