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热水浴还原法制备Gd_(2)O_(2)S:Pr闪烁陶瓷及性能优化

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硅酸盐学报 2024年第3期52卷 812-819页

作者：杜永笑罗朝华孙靖涵庄翊君刘永福孙鹏蒋俊宁波大学材料科学与化学工程学院浙江宁波315211 中国科学院宁波材料技术与工程研究所浙江宁波315201

硫氧化钆(Gd_(2)O_(2)S,GOS)闪烁陶瓷是一种具有高光输出、低余辉与高X射线阻止能力的闪烁材料,被广泛用于核医学影像和安全检查等领域。然而,GOS粉体合成过程复杂,组分精确配比与第二相难以控制,导致高品质GOS闪烁陶瓷制备依然存在较... 详细信息

硫氧化钆(Gd_(2)O_(2)S,GOS)闪烁陶瓷是一种具有高光输出、低余辉与高X射线阻止能力的闪烁材料,被广泛用于核医学影像和安全检查等领域。然而,GOS粉体合成过程复杂,组分精确配比与第二相难以控制,导致高品质GOS闪烁陶瓷制备依然存在较大挑战。针对这些问题和挑战:此项研究采用热水浴还原法制备了不同摩尔配比的(Gd_(1–x)Pr_(x))_(2)O_(2)S闪烁陶瓷材料,探究了不同形貌、粒度的氧化钆(Gd2O3)原料对Gd_(2)O_(2)S粉体的显微结构和光学性能影响。结果表明:亚微米级Gd_(2)O_(3)相较于纳米Gd_(2)O_(3)所合成的Gd_(2)O_(2)S:Pr粉体及闪烁陶瓷都具有更高的荧光强度,通过弱还原气氛下预烧结与热等静压后处理之后的Gd_(2)O_(2)S闪烁陶瓷具有较高的下相对密度和光学性能。在Pr^(3+)掺杂量(摩尔分数)x=0.2%时,闪烁陶瓷荧光强度达到最大值,并且在513 nm波长处透过率达到31%。本研究成功开发了一种简单而成本低廉的陶瓷制备工艺,该工艺无副产物污染,有望基于此工艺,大规模生产高性能Gd_(2)O_(2)S闪烁陶瓷。

关键词：闪烁陶瓷硫氧化钆氧化钆显微结构光学性能

蒙古—鄂霍次克洋俯冲的火成岩记录:来自大兴安岭花岗岩类的证据

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地质论评 2024年第S1期70卷 12-14页

作者：刘继旭刘翠邓晋福罗照华贺国奇刘庆中国地质大学(北京)地球科学与资源学院北京100083

大兴安岭地区出露大规模的中生代花岗岩类岩石,它们的形成与蒙古—鄂霍次克洋或古太平洋的关系仍具有争论(杨华本等,2020;王亚东等,2023)。本研究通过野外调查采样,对大兴安岭北部黑河—白石砬子一带附近出露的18个花岗岩类岩石样品进... 详细信息

大兴安岭地区出露大规模的中生代花岗岩类岩石,它们的形成与蒙古—鄂霍次克洋或古太平洋的关系仍具有争论(杨华本等,2020;王亚东等,2023)。本研究通过野外调查采样,对大兴安岭北部黑河—白石砬子一带附近出露的18个花岗岩类岩石样品进行了岩石学、地质年代学和地球化学研究。

关键词：大兴安岭地区早侏罗世岩石组合岩浆来源蒙古—鄂霍次克洋

Magma Origin and Evolution of Tengchong Cenozoic Volcanic Rocks from West Yunnan,China:Evidence from Whole Rock Geochemistry and Nd-Sr-Pb Isotopes

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 867-878页

作者： LI Dapeng luo zhaohua LIU Jiaqi CHEN Yuelong JIN Ye State Key Laboratory of Geological Processes and Mineral Resources School of Earth Science and ResourcesChina University of Geosciences Institute of Geology and Geophysics Chinese Academy of Sciences School of Ocean Sciences China University of Geosciences

Tengchong Cenozoic volcanics that have record key information on the tectonic evolution and mantle features of the southeast margin of the Tibetan Plateau are of great importance because of its unique eruption history spanning the entire Quaternary period. Magma origin and evolution of Tengchong Cenozoic volcanic rocks were studied on the basis of Nd-Sr-Pb isotope and major and trace element data from different eruptions in the Ma＇anshan area. Different samples within one eruption show relative identical lithologies, chemical and isotopic compositions. However, the geochemical features for the five eruptions are distinct from each other. These volcanic rocks show low Mg# values （〈45）, moderate to high fractionation of LREEs and HREEs, and enrichment of Pb and Ba and depletion of Nb. Tengchong Cenozoic volcanic rocks were derived from an enriched mantle based on Nd-Sr-Pb isotopic studies. And lines of evidence show that crustal contamination should be involved before the eruption of different periods of Tengchong Cenozoic volcanic rocks. Older subducted components may be responsible for adakite recycling at various stages of evolution, which results in the origin of the enriched mantle source magma accounting for the isotopic features of Tengchong Cenozoic volcanic rocks. Segregated primitive magma pulsating injected into magma chamber, fractional crystallized and contaminated with crust component. Finally, magmas with distinct chemical and isotopic compositions for each eruption formed. The extension of the northeast segment of the Yingjiang tectonic belt triggered the pulsating eruption of the Cenozoic volcanics in the Tengchong area.

关键词： Cenozoic volcanism Nd-Sr-Pb isotopes geochemistry Tengchong

Collision Tectonics between the Tarim Block(Basin)and the Northwestern Tibet Plateau:New Observations from a Multidisciplinary Geoscientific Investigation in the Western Kunlun Mountains

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Acta Geologica Sinica(English Edition) 2001年第2期75卷 126-132页

作者： XIAO Xuchang LIU Xun GAO Rui Houn KAO luo zhaohua Institute of Geology Chinese Academy of Geological Sciences Institute of Earth Sciences Academia SinicaTaipeiChina China University of Geosciences

New results from deep seismic reflection profiling, wide-angle reflection-refraction profiling and broadband seismic experiments reveal that a series of south-dipping reflectors occur on the southern margin of the Tarim block (basin). However, it is these south-dipping structures that are intercepted by another series of north-dipping reflectors at depths from 30 to about 150 km beneath the foreland of the W Kunlun Mountains. No evidence from the above geophysical data as well as geochemical and surface geological data indicate the southward subduction of the Tarim block beneath the W Kunlun Mountains (NW Tibet plateau), forming the so-called “two-sided subduction” model for the Tibet plateau as proposed by previous studies. So the authors infer that the tectonic interaction between the Tarim block and the W Kunlun block was chiefly affected by a “horizontal compression in opposite directions”, which brought about “face-to-face contact” between these two lithospheric blocks and led to the thickening, shortening and densifying of the lithosphere. Hence a “delamination” was formed due to the gravitational instability created by the thickening and densifying; then alkaline basic volcanic rocks (mainly shoshonite series) was erupted along the northern margin of the Tibet plateau owing to the delamination. This inference for the formation of the alkaline basic volcanics has been confirmed by recent geochemical and petrological studies in Tibet, indicating that different contacts control different magmatic activities: the alkali basalts are always developed in the “horizontal shortening boundary (contact)” on the northern margin of the Tibet plateau, while the muscovite granite and two-mica granite (leucogranite) in the “subductional contact” on the southern margin of the Tibet plateau.

关键词： collision tectonics deep structure NW Tibet plateau

Trace-element of Tuoyun cli-nopyroxene:Implication for the deep processes of litho-spheric mantle beneath the southwest Tianshan,West China

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Chinese Science Bulletin 2001年第14期46卷 1206-1211页

作者： ZHENG Jianping LU Fengxiang S.Y.O’Reilly luo zhaohua Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Department of Earth and Planetary Sciences Macquarie UniversitySydneyNSW2109Australia Faculty of Earth Sciences China University of GeosciencesBeijing 100083China

Based on the LAM-ICPMS analytic results on the trace elements of clinopyroxenes in peridotitic xenoliths occurring in early-Cretaceous basalts from western Xinjiang, the properties and the deep processes, including partial melting and mantle metasomatism, of the subcontinental lithospheric mantle beneath the Tuoyun Basin are analyzed. In the northern edge of the Tarim Basin (southwest Tian-shan), the Mesozoic subcontinental lithosphere which has experienced the effect of partial melting (<10%) and intricate mantle metasomatism is characterized by Phanerozoic ’ocean-type’ mantle. The superposed influence of SiO2-un-saturated silicate melt and carbonate melt probably results in the metasomatic medium which resembles the hydrous silicated carbonate melt in some aspects. By comparing Tuoyun mantle with Cenozoic main mantle beneath eastern China, the properties are similar, while the former shows finer grain and higher diopside content of the peridotites and more conspicuous modal metasomatism.

关键词： west China mantle clinopyroxene LAM-ICPMS mantle heterogeneity deep process.

Crystal Growth and Crystallization Time Scales of the Panzhihua Layered Intrusion:Constraint from Crystal Size Distribution

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1428-1439页

作者： LI Xuejun luo zhaohua LI Xiaowei WANG Yu YANG Zongfeng LI Jie LIU Xiao State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

The Panzhihua layered intrusions is generated closely related to the Emeishan *** paper analyzes the spatial distribution of plagioclase and *** quantitative texture analysis of 2209 plagioclase shows that the characteristic length of plagioclase is 0.54 to 0.96 mm,the intercept variation range is large,from-0.67 to 0.96,and the slope is-1.85 to-1.04,the Aspect Ratio shows from 1.84 to 2.59 and fractal dimension D is 1.908–*** quantitative texture analysis of 2342 pyroxene shows that the characteristic length of pyroxene is 0.38–0.64 mm,the intercept shows from 0.46 to 2.26,The slope ranges from-2.6 to-1.47,the Aspect Ratio value varies from 1.53 to 1.71,the fractal dimension D is 0.93 to *** the CSDs results of the Panzhihua intrusions indicate that plagioclase and pyroxene form in an open magma system and undergo four replenishment of magma *** plagioclase crystals do not grow as the lathlike shape,and the fractal growth leads to complex crystal *** plagioclase undergoes deformation compaction during the crystal process,and then is *** pyroxene crystals grow along an approximately triaxial ratio and undergo texture adjustment and small crystal dissolution *** all crystals in magma system grows up to 2 mm,the pyroxene undergoes cumulation in the Panzhihua layered *** plagioclase crystallization time scale is 171.23–304.41 years,representing that the crystallization is the more uniform in central part of the *** nucleation density continuously increases during the crystallization process of the magma *** time scale to reach the final maximum crystal nucleation density is 15.28–58.98 years.

关键词： crystal size distribution crystallization time scales layered intrusions Emeishan large igneous province Panzhihua

LA-ICP-MS Zircon U-Pb Geochronology of the Fine-grained Granite and Molybdenite Re-Os Dating in the Wurinitu Molybdenum Deposit,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1057-1066页

作者： Cui LIU Jinfu DENG Weiqiong KONG Liquan XU Guochun ZHAO zhaohua luo Ning LI State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences (Beijing) Beijing 100083 China Graduate University of Chinese Academy of Sciences Beijing 100049 China The Fourth Institute of Geological and Mineral Exploration of Gansu Province Jiuquan Gansu 735000 China Geological Survey Institute of Inner Mongolia Hohhot Inner Mongolia 010020 China

The Wurinitu molybdenum deposit,located in Honggor,Sonid Left Banner of Inner Mongolia,China,is recently discovered and is considered to be associated with a concealed fine-grained granite impregnated with *** wall rocks are composed of Variscan porphyritic-like biotite granite and the Lower Ordovician Wubin'aobao ***-ICP-MS zircon U-Pb dating of the fine-grained granite reveals two stages of zircons,one were formed at 181.7±7.4 Ma and the other at 133.6±3.3 *** latter age is believed to be the formation age of the fine-grained granite,while the former may reflect the age of inherited zircons,based on the morphological study of the zircon and regional geological *** Re-Os model age of molybdenite is 142.2±2.5 Ma,which is older than the diagenetic age of the fine-grained *** the authors believe that the metallogenic age of the Wurinitu molybdenum deposit should be nearly 133.6±3.3 Ma or slightly later,i.e.,Early *** with regional geological background research,it is speculated that the molybdenum deposits were formed at the late Yanshanian orogenic cycle in the Hingganling-Mongolian orogenic belt,belonging to the relaxation epoch posterior to the compression and was associated with the closure of the Mongolia-Okhotsk Sea.

关键词： fine-grained granite LA-ICP-MS zircon U-Pb geochronology molybdenite Re-Os dating Wurinitu molybdenum deposit Inner Mongolia

Sodium-rich volcanic rocks and their relationships with iron deposits in the Aqishan-Yamansu belt of Eastern Tianshan,NW China

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Geoscience Frontiers 2020年第2期11卷 697-713页

作者： Zhiyuan Sun WangJingbin Yuwang Wang Lingli Long zhaohua luo Xiaohua Deng Qitao Hu Menglong Wang Beijing Institute of Geology for Mineral Resources Beijing 100012China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Shanshan Baodi Mining Limited Liability Company Shanshan 838204XinjiangChina

The volcanic rocks hosting the iron deposits in the Aqishan–Yamansu metallogenic belt are *** geochronology,petrography,and geochemistry of minerals and sodium-rich rocks as well as the relationship between these rocks and the iron deposits are ***,the ore-hosting volcanic rocks are sodiumrich(the averages of Na2O and Na2O/K2O are 4.31 wt.%and 8.56,respectively)and belong to the calc-alkaline *** are enriched in LREEs and LILEs(Ba,U,K,and Sr),but depleted in HFSEs(Nb,Ta,and Ti).SHRIMP zircon U–Pb dating of the crystal tuff in the Aqishan Formation and the dacite in the Tugutu Bulak Formation yields ages of 337.52.3 Ma(n?15,MSWD?0.85)and 313.03.3 Ma(n?13,MSWD?0.74),respectively,indicating that the sodium-rich volcanic rocks formed from the early–late *** microprobe data from plagioclases demonstrate that albites and/or oligoclases were formed in the basic–intermediate–acid volcanic *** stages of albitization are identified,and the latter is likely attributed to the dissolution of iron in the Aqishan–Yamansu *** sodium-rich volcanic rocks probably formed by the interaction between volcanic lava and seawater after volcanoes erupted on the seafloor;meanwhile,the albites formed by element substitution in a low-metamorphic *** spatiotemporal coupling relationship between sodium-rich volcanic rocks and iron deposits in the Aqishan–Yamansu belt is *** dissolved from the dark minerals of basic–intermediate volcanic rocks through sodium metasomatism is one of the material sources for the iron deposits.

关键词： Sodium-rich volcanic rock Geochronology Rock geochemistry Yamansu metallogenic belt Eastern tianshan orogenic belt

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流体地球科学与地球系统科学

地学前缘 2018年第6期25卷 277-282页

作者：罗照华中国地质大学地质过程与矿产资源国家重点实验室

近年来,地球系统科学逐渐成为地球科学的新趋势,但固体地球科学尚难于融入其中。其根本原因在于地球系统科学属于系统科学或复杂科学的组成部分,而固体地球科学其本质上属于理想科学的范畴,以研究线性地球过程为主,或者以理想科学的手... 详细信息

近年来,地球系统科学逐渐成为地球科学的新趋势,但固体地球科学尚难于融入其中。其根本原因在于地球系统科学属于系统科学或复杂科学的组成部分,而固体地球科学其本质上属于理想科学的范畴,以研究线性地球过程为主,或者以理想科学的手法研究非线性地球过程。流体地球科学不仅研究地球的流体系统,也研究流体系统与固体系统的强和弱相互作用,是固体地球科学融入地球系统科学的唯一途径。

关键词：流体地球科学固体地球科学地球系统科学复杂科学非线性地球过程