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北京市51所三级医院内镜超声微探头清洗消毒现状调查
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作者 郭新月 王依晗 +1 位作者 秦一鸣 贺琰 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第9期1157-1162,共6页
目的了解北京市三级医院内镜超声微探头清洗消毒现状。方法采用便利抽样法抽取北京市51所三级医院,对内镜中心护士长进行问卷调查,调查内容包括内镜超声微探头预处理、清洗、消毒、灭菌、生物学检测、消毒追溯、储存维修等情况。结果51... 目的了解北京市三级医院内镜超声微探头清洗消毒现状。方法采用便利抽样法抽取北京市51所三级医院,对内镜中心护士长进行问卷调查,调查内容包括内镜超声微探头预处理、清洗、消毒、灭菌、生物学检测、消毒追溯、储存维修等情况。结果51所三级医院中甲等医院33所,乙等医院18所。76.47%(39所)的医院对使用后的超声微探头进行床旁预清洗,内镜超声微探头床旁预处理方式主要包括酶液湿巾擦拭(38.47%,15/39)和乙醇湿巾擦拭(30.77%,12/39);96.08%(49所)的医院对超声微探头进行手工清洗,手工清洗方法以“酶洗-擦洗-擦干”为主(58.82%,30所)。96.08%(49所)的医院对使用后的微探头进行消毒,以化学消毒剂浸泡消毒为主要方法(65.31%,32所);43.14%(22所)的医院对微探头进行灭菌,灭菌方法主要为0.2%~0.35%过氧乙酸浸泡10~15 min(77.27%,17/22);41.18%(21所)的医院定期对微探头进行生物学监测;37.25%(19所)的医院对微探头的清洗消毒流程进行追溯;88.24%(45所)的医院定期对微探头进行检查、保养、维修。结论北京市51所三级医院对内镜超声微探头的预处理、清洗、消毒、灭菌及生物学监测情况存在较大差异,建议尽快制定相关专家共识或指南,从而规范内镜超声微探头的清洗消毒工作。 展开更多
关键词 内镜 超声微探头 清洗 消毒 调查
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湘南铜山岭铜铅锌矿床闪锌矿矿物化学特征及其成矿指示意义
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作者 黄旭栋 陆建军 +4 位作者 高剑峰 章荣清 SIZARET Stanislas 马东升 王汝成 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2024年第2期387-402,共16页
为探讨湘南铜山岭铜铅锌矿床的形成过程,本文对不同类型矿石中的闪锌矿开展了电子探针成分分析。结果表明,Fe主要通过直接置换Zn的方式进入闪锌矿,Cd可能通过与Fe耦合置换Zn的方式(Cd^(2+)+Fe^(2+)←→2Zn^(2+))进入闪锌矿,含铜矿石的... 为探讨湘南铜山岭铜铅锌矿床的形成过程,本文对不同类型矿石中的闪锌矿开展了电子探针成分分析。结果表明,Fe主要通过直接置换Zn的方式进入闪锌矿,Cd可能通过与Fe耦合置换Zn的方式(Cd^(2+)+Fe^(2+)←→2Zn^(2+))进入闪锌矿,含铜矿石的闪锌矿中可能含有亚显微级黄铜矿包裹体。闪锌矿的Fe、Cd含量和Fe/Zn、Zn/Cd值的变化指示近端内矽卡岩、近端外矽卡岩和远端矽卡岩矿体依次形成,铜硫化物-石英脉、铜铅锌硫化物-石英脉和铅锌硫化物-石英脉矿体依次形成,碳酸盐交代型矿体形成较晚。结合矿床地质和闪锌矿矿物学特征,本文认为铜山岭铜铅锌矿床可能存在两期流体出溶,早期出溶温度较高的含Cu、Pb、Zn流体,引起近端内矽卡岩、近端外矽卡岩、远端矽卡岩、铜硫化物-石英脉和铜铅锌硫化物-石英脉矿化;晚期出溶温度较低的含Pb、Zn流体,导致铅锌硫化物-石英脉型和碳酸盐交代型矿化。 展开更多
关键词 闪锌矿 电子探针 矿物化学 矽卡岩铜铅锌矿床 成矿过程 铜山岭
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Mapping the metabolic responses to oxaliplatin-based chemotherapy with in vivo spatiotemporal metabolomics
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作者 Mariola Olkowicz Khaled Ramadan +4 位作者 Hernando Rosales-Solano Miao Yu Aizhou Wang Marcelo Cypel Janusz Pawliszyn 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第2期196-210,共15页
Adjuvant chemotherapy improves the survival outlook for patients undergoing operations for lung metastases caused by colorectal cancer (CRC). However, a multidisciplinary approach that evaluates several factors relate... Adjuvant chemotherapy improves the survival outlook for patients undergoing operations for lung metastases caused by colorectal cancer (CRC). However, a multidisciplinary approach that evaluates several factors related to patient and tumor characteristics is necessary for managing chemotherapy treatment in metastatic CRC patients with lung disease, as such factors dictate the timing and drug regimen, which may affect treatment response and prognosis. In this study, we explore the potential of spatial metabolomics for evaluating metabolic phenotypes and therapy outcomes during the local delivery of the anticancer drug, oxaliplatin, to the lung. 12 male Yorkshire pigs underwent a 3 h left lung in vivo lung perfusion (IVLP) with various doses of oxaliplatin (7.5, 10, 20, 40, and 80 mg/L), which were administered to the perfusion circuit reservoir as a bolus. Biocompatible solid-phase microextraction (SPME) microprobes were combined with global metabolite profiling to obtain spatiotemporal information about the activity of the drug, determine toxic doses that exceed therapeutic efficacy, and conduct a mechanistic exploration of associated lung injury. Mild and subclinical lung injury was observed at 40 mg/L of oxaliplatin, and significant compromise of the hemodynamic lung function was found at 80 mg/L. This result was associated with massive alterations in metabolic patterns of lung tissue and perfusate, resulting in a total of 139 discriminant compounds. Uncontrolled inflammatory response, abnormalities in energy metabolism, and mitochondrial dysfunction next to accelerated kynurenine and aldosterone production were recognized as distinct features of dysregulated metabolipidome. Spatial pharmacometabolomics may be a promising tool for identifying pathological responses to chemotherapy. 展开更多
关键词 Pulmonary metastases Colorectal cancer Adjuvant chemotherapy In vivo lung chemo-perfusion Solid-phase microextraction(SPME)microprobes Spatial metabolomics
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白云鄂博矿床黄河矿的矿物学研究
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作者 陈彪 金海龙 +3 位作者 孙庆 李强 刘雁江 贾晓琪 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2024年第5期987-997,共11页
Ba-REE氟碳酸盐类矿物作为白云鄂博矿床中一类特有的稀土矿物,前人开展了大量基础晶体化学方面的研究,而对其共生组合、化学成分等方面研究则相对较少。对矿体中发现的一些粗粒黄河矿晶体,本文利用场发射扫描电镜、场发射电子探针等分... Ba-REE氟碳酸盐类矿物作为白云鄂博矿床中一类特有的稀土矿物,前人开展了大量基础晶体化学方面的研究,而对其共生组合、化学成分等方面研究则相对较少。对矿体中发现的一些粗粒黄河矿晶体,本文利用场发射扫描电镜、场发射电子探针等分析测试仪器对其开展相关研究。结果表明,黄河矿多呈脉状、团聚状富集于矿石之中,与重晶石、萤石、氟碳酸盐矿物等紧密共生,具有典型的热液矿物分布特征。电子探针分析显示,黄河矿的化学成分主要为BaO(35.28%)和轻稀土元素(39.37%),此外由于元素的类质同相替换,部分形成黄河矿-氟碳铈钡矿-氟碳钙铈矿等系列矿物体衍生构造。结合前人的黄河矿年代学证据及本次的矿物共生组合关系,认为白云鄂博矿床中的黄河矿主要结晶沉淀于古生代的富F、Ba和REE的热液流体中,而其REE元素则主要来源于早期形成的稀土矿物的再活化。 展开更多
关键词 白云鄂博矿 黄河矿 化学成分 扫描电镜 电子探针
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恐龙时代之U-Pb定年
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作者 许润泽 刘睿 《大学化学》 CAS 2024年第9期243-247,共5页
以一位考古学教授在四川自贡恐龙遗址考察引发的遐想为载体,介绍了U-Pb定年法的基本原理,以及样品采集、样品处理后的分析方法和检测结果处理,全面地科普了U-Pb定年法的相关知识。同时,本文介绍了自贡地区的恐龙文化及产业,向读者展现... 以一位考古学教授在四川自贡恐龙遗址考察引发的遐想为载体,介绍了U-Pb定年法的基本原理,以及样品采集、样品处理后的分析方法和检测结果处理,全面地科普了U-Pb定年法的相关知识。同时,本文介绍了自贡地区的恐龙文化及产业,向读者展现恐龙之都的魔力。 展开更多
关键词 U-PB法 同位素地质年代学 地球化学 电感耦合等离子体质谱 高分辨率离子探针
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新疆且末县青塔山岩体地球化学特征及其地质意义
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作者 李少文 周传芳 +2 位作者 杨华本 王久懿 梁中恺 《中国地质调查》 CAS 2024年第3期59-67,共9页
青塔山岩体位于东昆仑山西部,岩体的形成时代、环境、岩石类型尚存在争议,对于其成岩的物理化学条件和源区特征的研究程度较低。在系统开展岩石学和岩相学研究的基础上,对黑云母、斜长石和角闪石等主要造岩矿物进行了成分分析,厘定其成... 青塔山岩体位于东昆仑山西部,岩体的形成时代、环境、岩石类型尚存在争议,对于其成岩的物理化学条件和源区特征的研究程度较低。在系统开展岩石学和岩相学研究的基础上,对黑云母、斜长石和角闪石等主要造岩矿物进行了成分分析,厘定其成岩的物理化学条件,进一步约束岩石成因。研究表明:青塔山岩体的岩性为英云闪长岩,脉体岩性为石英闪长岩;岩体中斜长石为中长石和拉长石,黑云母为镁质黑云母,角闪石为镁角闪石,斜长石发育反环带,应为岩浆混合所致;黑云母的结晶温度为684~693℃,结晶压力为(1.86~2.01)×10^(8) Pa,平均值为1.92×10^(8) Pa,对应结晶深度为6.90~7.46 km,平均7.12 km,属于中深成相。岩体形成时氧逸度较低,为-17.34~-17.04。矿物化学特征显示,青塔山岩体中黑云母的物质来源为钙碱性造山岩套,其形成与壳幔混源岩浆有关。研究成果可为研究青塔山地区晚三叠世—早侏罗世岩浆演化历史提供依据。 展开更多
关键词 英云闪长岩 电子探针 斜长石环带 矿物温压计 昆仑山
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Eruption of the Continental Flood Basalts at -259 Ma in the Emeishan Large Igneous Province, SW China: Evidence from Laser Microprobe ^(40)Ar/^(39)Ar Dating 被引量:16
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作者 HOU Zengqian CHEN Wen LU Jiren 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期514-521,共8页
A suite of continental flood basalts sampled over a vast exposure and stratigraphic thickness in the Emeishan large igneous province (LIP), SW China was investigated for laser microprobe ^40Ar/^39Ar dating. There ar... A suite of continental flood basalts sampled over a vast exposure and stratigraphic thickness in the Emeishan large igneous province (LIP), SW China was investigated for laser microprobe ^40Ar/^39Ar dating. There are two ^40Ar/^39Ar age groups for these basalts, corresponding to 259-246 Ma and 177-137 Ma, respectively. A well-defined isochron gives an eruption age of huge quantities of mafic magmas at 258.9±3.4 Ma, which is identical to previous dating and paleontological data. Much younger ^40Ar/^39Ar ages for some basalts with Iow-greenschist metamorphic facies probably recorded a late thermo-tectonic event caused by collision between the Yangtze and Qiangtang continental blocks during the Mesozoic, which resulted in the reset of argon isotope system. The ^40Ar/^39Ar age data, we present here, combined with previous dating and paleontological data, suggest relatively short duration (about 3 Ma) of mafic volcanism, which have important implication on mantle plume genesis of the Emeishan continental flood basalts in the LIP. 展开更多
关键词 laser microprobe ^40Ar/^39Ar age continental flood basalts EMEISHAN large igneous province
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Structures of Syn-deformational Granites in the Longquanguan Shear Zone and Their Monazite Electronic Microprobe Dating 被引量:10
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作者 ZHANG Jinjiang ZHAO Lan LIU Shuwen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期864-874,共11页
The Longquanguan shear zone is an important structural belt in the North China Craton, separating the underlying Fuping complex from the overlying Wutai complex. This shear zone has experienced three episodes of defor... The Longquanguan shear zone is an important structural belt in the North China Craton, separating the underlying Fuping complex from the overlying Wutai complex. This shear zone has experienced three episodes of deformation: the first and main episode is a ductile top-to-ESE shear along the gently northwest-west dipping foliations, while the other two episodes are later collapse sliding. Prolonged granites parallel to the shear foliations make one of the main compositions of the Longquanguan shear zone. These granites experienced deformation to form mylonitic rocks when they emplaced during the first episode of deformation. Structural characters of the granites and their contacts to the country rocks indicate that these granites possibly resulted from in-situ partial remelting by shearing, i.e., they are syn-deformational granites. Monazites in these mylonitic granites are magmatic minerals and their crystallization ages may represent ages of the magmatic events, and also the ages for the main deformation of the Longquanguan shear zone. Monazite electronic microprobe dating were carried on two samples of granite, which gives multiple peak ages, among which 1,846 Ma and 1,877 Ma are the main peak ages for the two samples. These ages represent the main deformation of the Longquanguan shear zone, which is consistent with the main regional geological event at about 1,850 Ma caused by the collision between the Eastern and Western Blocks in North China. The good match between the monazite ages and the corresponding regional tectono-thermal events shows the feasibility and reliability of monazite electronic microprobe dating. 展开更多
关键词 Longquanguan shear zone syn-deformational granite monazite electronic microprobe dating
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STUDY ON OCCURENCE FORM OF PLATINUM IN XINJIE Cu-Pt DEPOSIT BY NAA AND SCANNING PROTON MICROPROBE 被引量:1
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作者 李晓林 朱节清 +5 位作者 谷英梅 邬显慷 童纯菡 汪云亮 帅德权 张成江 《Nuclear Science and Techniques》 SCIE CAS CSCD 1995年第4期212-216,共5页
A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to th... A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to the enriched Pt-Pd type.The element concentration maps of scanning micro-PIXE for the ores show that the occurence form of Pt is independent arsenide minerals. No PGE were detected in chalcopyrite of Xinjie Cu-Pt deposit. These information are economically beneficial to the mineral smelting process. 展开更多
关键词 Platinum group elements Neutron activation analysis Scanning proton microprobe China
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THE SCANNING NUCLEAR MICROPROBE AT SINR
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作者 朱节清 李民乾 +4 位作者 毛羽 陈汉民 谷英梅 杨长义 盛康龙 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第4期203-210,共8页
This paper describes the scanning nuclear microprobe facilities established at the Shanghai Institute of Nuclear Research. The Russion quadruplet constructed with four magnetic quadrupolets is used for microbeam forma... This paper describes the scanning nuclear microprobe facilities established at the Shanghai Institute of Nuclear Research. The Russion quadruplet constructed with four magnetic quadrupolets is used for microbeam formation. The long focus of the lens makes the working distance long enough to accommodate the scanning coils and the detectors for PIXE, RBS, RFS, NRA and SE experiments. A 5 μm focussed beam is scanned continously by a pair of coils. A multiparameter multidetector data system for the nuclear microprobe is based on the idea of Total quantitative scanning analysis (TQSA) suggested by Melbourne University. A digital graphic displayer is a good substitute for an ordinary storage oscilloscope for on- line scanned area monitoring. The new microprobe meets high demands of biologists and geologists on applications. 展开更多
关键词 Nuclear microprobe AMOEBA proleus DEEP-SEA MANGANESE NODULES
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Scanning proton microprobe microanalysis for the assessmentof homogeneity of IAEA urban dust reference materials
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作者 Zhang Yuan-xun Gu Ying-mei +1 位作者 Zhu Ji-fang Zhu Jie-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第3期9-13,共5页
In order to develop new reference materials for microanalytical nuclear techniques, scanning proton microprobe (SPM) technique was used to determine homogeneity level within 100×200 μm 2 micro area on the small ... In order to develop new reference materials for microanalytical nuclear techniques, scanning proton microprobe (SPM) technique was used to determine homogeneity level within 100×200 μm 2 micro area on the small pieces of IAEA urban dust reference materials. The experimental methods were described in detail. The results show that IAEA 396A/M Vienna urban dust is homogeneous enough for small sample analysis of standard reference material (SRM). 展开更多
关键词 standard reference material (SRM) scanning proton microprobe urban dust.
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STUDY ON THE MORPHOLOGY OF POLYVINYL CHLORIDE/POLYSTYRENE BLENDS BY ELECTRON MICROPROBE ANALYSIS
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作者 Zheng-ping Fang Gen-lin Wang +2 位作者 Guo-ping Cai Cheng-wei Xu Jie Qian Institute of Polymer Composites, Zhejiang University, Hangzhou 310027, China College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第5期437-441,共5页
The morphology of polyvinyl chloride/polystyrene (PVC/PS) blend samples with different mass ratios, prepared by means of solution casting and melt mixing, have been successfully examined by electron microprobe analysi... The morphology of polyvinyl chloride/polystyrene (PVC/PS) blend samples with different mass ratios, prepared by means of solution casting and melt mixing, have been successfully examined by electron microprobe analysis (EMP). This experiment was performed in a scanning electron microscope attached to an energy dispersive X-ray analyzer. Differential scanning calorimetry was also used to investigate the phase separation of the blends. The results show that PVC and PS are incompatible and the blends have sea-islands phase structures. Blends prepared via melt mixing have finer phase-dispersion than those prepared via solution casting. 展开更多
关键词 electron microprobe analysis polyvinyl chloride/polystyrene blends MORPHOLOGY
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Development of a soft X-ray microprobe for single cell radiobiology 被引量:1
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作者 CHEN Liang YAN Jingwen JIANG Shiping YU Yang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第2期82-86,共5页
An X-ray microprobe for radiobiological studies was developed which deliver precise doses of radiation to the selected individual cells.The facility used synchrotron radiation as soft X-ray source.A zone plate combini... An X-ray microprobe for radiobiological studies was developed which deliver precise doses of radiation to the selected individual cells.The facility used synchrotron radiation as soft X-ray source.A zone plate combining with a pinhole produced a fine probe from bending magnet for single cell irradiating with defined doses.The diameter of microprobe at the target position was about 2 μm by scanning a knife-edge with an AXUV photo diode.The fluxes of soft X-rays at 516.7 eV(2.4 nm) were about 5.4×104 photons/s.100mA measured with the photo diode.The absorbed dose rate for typical yeast cells was about 11.34 Gy/s with the storage current of 100 mA.A preliminary experiment for yeast cells irradiation has shown that the microprobe had a definite biological effect for radiobiological investigations.The soft X-ray microprobe at "water window" region has provided a useful tool for single cell irradiating damage and a capability of individually irradiating a certain numbers of cells each time. 展开更多
关键词 X射线微探针 放射生物学 单细胞 软X射线源 辐射生物学效应 光电二极管 照射剂量 同步辐射
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The Petrography, Mineralography and Microprobe Analysis on New Exploratory Excavation Phase in Sarcheshmeh Copper Mine Pit and Comparing Them with Existing Data from the Other Area in South West Sarcheshmeh
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作者 Mehdi Abdollahy Riseh Mansur Vosooghi Abedini +1 位作者 Mohammad Hashem Emami Seyed Jamal Sheikh Zakariaei 《Open Journal of Geology》 2017年第2期162-181,共20页
Kerman region where Sarcheshmeh zone is located includes the end part of Uremia-Dokhtar Zone. Extrusive igneous group in Sarcheshmeh is as follows: 1) andesite and 2) rhyodacite. The group of intrusive igneous rocks i... Kerman region where Sarcheshmeh zone is located includes the end part of Uremia-Dokhtar Zone. Extrusive igneous group in Sarcheshmeh is as follows: 1) andesite and 2) rhyodacite. The group of intrusive igneous rocks includes 1) porphyry granite, 2) porphyry granodiorite, and 3) porphyry diorite. Nochoon mine is located at 4 km of southwest of Sarcheshmeh copper mine and it comprises of a group of extrusive igneous rocks as follows: 1) andesite, and 2) dacite. Based on results of microprobe analysis, pyroxene mineral’s composition in these rocks of diopside and augite indicates amphiboles of composite zone of magnesium hosting type and existing plagioclases in regional rock for labradorite and bitonit composition. The most common compounds are chlorite with formula among antigorite and amosite. Comparison of magnetite mineralization in Sarcheshmeh and Nochoon indicates vein mineralization in Nochoon and disseminated granulation in Sarcheshmeh and particularly concerning to chalcopyrite, Nochoon includes more veins than Sarcheshmeh. 展开更多
关键词 PETROGRAPHY microprobe Chemical Analysis Sarcheshmeh Mine KERMAN
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Measurement of transient thickness between the body and graze layers of ancient porcelains using microprobe EDXRF technique 被引量:1
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作者 PENGZi-Cheng LEUNGPL +1 位作者 CHENGPK LIM 《Nuclear Science and Techniques》 SCIE CAS CSCD 2004年第6期348-351,共4页
The oxide contents of TiO2, MnO, SrO and Fe2O3 in the body and graze layers of the Jiao-Tan-Xia (JTX) and Lao-Hu-Dong (LHD) porcelains in Southern Song Dynasty (1127-1279 A.D.) have been determined using an In- ternat... The oxide contents of TiO2, MnO, SrO and Fe2O3 in the body and graze layers of the Jiao-Tan-Xia (JTX) and Lao-Hu-Dong (LHD) porcelains in Southern Song Dynasty (1127-1279 A.D.) have been determined using an In- ternational Eagle-II μ-probe EDXRF spectrometer. The results show that the contents in the body are much different from those in the graze one. Therefore, the transient thickness (TT) between the body and graze layers can be meas- ured through determination of a distance of the drift change in the chemical contents. The TT average for the JTX porcelains is 161μm, while that for the LHD porcelains is 258μm, which are consistent with a range of 0.15-0.3mm in the Ru-Yao porcelains. The different TT is related to the variances in firing temperature and raw material for manu- facturing the respective porcelains. 展开更多
关键词 南宋瓷器 EDXRF微探针 微观结构 化学成分 X-射线荧光
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Microprobe Mapping of Rare Earth Element Distribution in Round Top Yttrofluorite Deposit
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作者 Nicholas E. Pingitore Jr. Margaret Piranian +1 位作者 Lorraine M. Negron Daniel Gorski 《Advances in Materials Physics and Chemistry》 2018年第1期15-31,共17页
The electron microprobe maps the spatial distribution of elements in a rock at a sub-mineral-grain scale to provide a basis for understanding mineralization processes and to determine optimal strategies for extraction... The electron microprobe maps the spatial distribution of elements in a rock at a sub-mineral-grain scale to provide a basis for understanding mineralization processes and to determine optimal strategies for extraction of valuable target elements. Round Top Mountain (near the town of Sierra Blanca, Hudspeth County, west Texas, USA) is a peraluminous rhyolite laccolith that is homogeneously mineralized at over 500 ppm rare earths, more than 70% of which are yttrium and heavy rare earths (YHREEs). The massive deposit is exposed at the surface as a mountain some 2 km in diameter and 375 m in height. Round Top Mountain also contains Li, Be, U, Th, Nb, Ta, Ga, Rb, Cs, Sn, and F. The valuable YHREEs are hosted in yttrofluorite, which is soluble in dilute sulfuric acid. Texas Mineral Resources Corporation proposes to surface mine, crush, and heap leach the deposit. The distribution of YHREEs, and that of other trace elements, is remarkably homogeneous at outcrop drill hole scale. Here we document that YHREE mineralization appears pervasive through the rhyolite at a millimeter scale. Back scattered electron (BSE) and characteristic X-ray maps reveal the fine grain size and apparently random and dispersed spatial distribution of the yttrofluorite that hosts Round Top’s valuable YHREEs. The yttrofluorite grains do not appear to cluster at special mineralized locations, e.g., in pores or along cracks in the rhyolite. The same is apparently true of such other potentially valuable minerals as cassiterite and uranium species. These findings confirm that the distribution of YHREEs in Round Top Mountain rhyolite is homogeneous through different orders of magnitude of scale, i.e., from outcrop (as seen in the companion work in this volume) to sub-thin section. The material thus is ideal for a heap leach operation where homogeneous feedstock is crucial to consistent and economic operation. The findings also confirm and explain why mechanical separation would prove very difficult and expensive due to the astronomical number of yttrofluorite grains in even a golf-ball-size piece of Round Top rhyolite. 展开更多
关键词 HEAVY RARE Earth Elements Yttrofluorite Electron microprobe Micromapping ROUND TOP
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钍石电子探针定年:记录小秦岭矿集区伟晶岩热液蚀变历史 被引量:1
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作者 赵海香 郑浩 Volker von SECKENDORFF 《地质学报》 EI CAS CSCD 北大核心 2023年第8期2563-2574,共12页
电子探针化学定年法(Chemical Th-U-total Pb Isochron Method,CHIME)以其原位、极高的空间分辨率、样品制备简单方便、不破坏样品、测试速度快、成本低等优点,被成功用于独居石、褐帘石、锆石、磷钇矿、晶质铀矿等副矿物定年,但应用于... 电子探针化学定年法(Chemical Th-U-total Pb Isochron Method,CHIME)以其原位、极高的空间分辨率、样品制备简单方便、不破坏样品、测试速度快、成本低等优点,被成功用于独居石、褐帘石、锆石、磷钇矿、晶质铀矿等副矿物定年,但应用于钍石定年仍不成熟。本文尝试利用电子探针对小秦岭矿集区元古宙伟晶岩脉中的钍石进行定年。显微镜下观察发现,热液钍石颗粒细小(<30μm),多与独居石共生,包裹在褐帘石中。我们对未发生蚀变或者蜕晶化的小颗粒钍石进行了电子探针Th-U-Pb化学法定年,得到的加权平均年龄为120.9±2.1 Ma(95%置信区间)。这一年龄与枪马金矿的矿化年龄一致,代表继该地区大规模花岗岩侵位活动之后,华北克拉通减薄过程中的又一次热液蚀变过程。 展开更多
关键词 钍石定年 电子探针 小秦岭 华北克拉通
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Mantle metasomatism for metaperidotite from Shuanggou ophiolite of Yunnan Province by proton microprobe
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作者 陈友红 朱节清 +4 位作者 邬显慷 谷英梅 张旗 徐平 李秀云 《Nuclear Science and Techniques》 SCIE CAS CSCD 1996年第2期99-102,共4页
MantlemetasomatismformetaperidotitefromShuanggouophioliteofYunnanProvincebyprotonmicroprobeChenYou-Hong(陈友红)... MantlemetasomatismformetaperidotitefromShuanggouophioliteofYunnanProvincebyprotonmicroprobeChenYou-Hong(陈友红);ZhuJie-Qing(朱节清)... 展开更多
关键词 地质学 示踪元素组成 质子微探针
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东昆仑黑石山含硫化物暗色包体及宿主正长岩成因及地质意义:年代学、矿物学、地球化学和Sr-Nd-Hf同位素证据 被引量:1
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作者 李治华 李碧乐 +3 位作者 王斌 孙亚明 史雨凡 于润涛 《岩石学报》 SCIE EI CAS CSCD 北大核心 2023年第3期742-762,共21页
黑石山铜铅锌矿床位于东昆仑造山带中段的五龙沟地区,矿区内的石英二长岩-正长岩发育有暗色微粒包体,本研究在包体中发现了硫化物。锆石U-Pb定年显示,正长岩形成于239.4±1.0Ma,具有富Si和K,贫Mg、Cr、Ni,明显的Eu负异常,富集大离... 黑石山铜铅锌矿床位于东昆仑造山带中段的五龙沟地区,矿区内的石英二长岩-正长岩发育有暗色微粒包体,本研究在包体中发现了硫化物。锆石U-Pb定年显示,正长岩形成于239.4±1.0Ma,具有富Si和K,贫Mg、Cr、Ni,明显的Eu负异常,富集大离子亲石元素、亏损高场强元素,较为富集的Sr-Nd-Hf同位素特征。暗色微粒包体由斜长石和角闪石组成,可见角闪石堆晶,贫硅、富钙、铝、碱和铁,Mg#值为38.37,具有明显的Eu负异常,轻重稀土分馏弱。结合宿主正长岩和暗色包体的矿物成分相似性和岩相学特征,本文认为暗色微粒包体与正长岩来自同一个岩浆房,属于同源岩浆包体,是岩浆房早期分离结晶相,被中酸性岩脉携带上升至正长岩熔体中,一起侵位至浅部地壳。综合岩石地球化学、同位素和矿物成分,本文认为正长岩是下地壳含水镁铁质岩石在压力较低条件下部分熔融的产物。暗色微粒包体中发育硫化物,且包体岩浆的硫含量远高于正长岩岩浆,指示岩浆房的早期分离结晶相带走了硫,使残余熔体贫硫。 展开更多
关键词 含硫化物暗色微粒包体 正长岩 锆石U-Pb定年 地球化学 SR-ND-HF同位素 电子探针 磷灰石
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西藏铁格隆南超大型铜(金)矿床白云母矿物学特征及地质意义
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作者 贺文 林彬 +4 位作者 宋英昕 方向 王勤 杨欢欢 李发桥 《地质学报》 EI CAS CSCD 北大核心 2023年第6期1938-1955,共18页
铁格隆南矿床产出了西藏班公湖-怒江成矿带多龙矿集区最大的斑岩-高硫型铜(金银)成矿系统。由于高硫型矿化与蚀变对斑岩型矿化和蚀变的广泛叠加,导致其成矿系统结构和成矿作用机制变得十分复杂,一定程度阻碍了其精细成矿模型的构建。本... 铁格隆南矿床产出了西藏班公湖-怒江成矿带多龙矿集区最大的斑岩-高硫型铜(金银)成矿系统。由于高硫型矿化与蚀变对斑岩型矿化和蚀变的广泛叠加,导致其成矿系统结构和成矿作用机制变得十分复杂,一定程度阻碍了其精细成矿模型的构建。本文基于铁格隆南矿床现有的勘查和研究成果,从矿物学的角度,以白云母为典型蚀变矿物,通过详细的镜下鉴定、扫描电镜和电子探针分析,详细揭示不同空间位置、不同产状白云母的矿物学特征和成因,探究其对铁格隆南矿床成矿机制的指示意义。结果显示,铁格隆南矿床的热液白云母主要由白云母端元、伊利石端元、绿鳞石端元以及少量钠云母端元组成。矿体中白云母与铜矿物具有成因联系。在深部的早期水岩反应中,白云母主要与黄铜矿伴生,热液蚀变斑岩形成的白云母呈现高Si低Al的特征,而热液蚀变砂岩呈高Al低Si的特征。随着流体向浅部继续运移,白云母共生的金属矿化转换为斑铜矿和铜蓝,多形成高Al低Si的白云母。相对于在侵入岩中产出的白云母,在砂岩中形成的白云母的Fe_(T)、Fe^(3+)、Na^(+)含量更高。侵入岩中形成富Fe^(2+)白云母,指示热液还原性较强。此外,在黄铁绢英岩化带较中—浅部产出的白云母常与较多高岭石和铜蓝、斑铜矿伴生,指示了热液中的SO_(2)发生聚集、温度降低、酸性增强并导致水岩反应增强和矿质沉淀的过程。综上,白云母与不同矿物组合及其地球化学特征,对成矿流体环境及勘查评价有良好的指示意义。 展开更多
关键词 白云母 矿化过程 扫描电镜 电子探针 铁格隆南矿床
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