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Minerogenetic Model for Two Types of Fluorite Deposits in Southeastern China

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 75-88页

作者： Li Changjiang Jiang Xuliang Zhejiang institute of Geology and mineral Resources, Hangzhou Liu Linqun Zhejiang institute of Geology and mineral Resources Hangzhou

On the basis of the studies of field geology, strontium, hydrogen and oxygen isotopes and REEgeochemistry, coupled with the dating of mineralization, the authors suggest a minerogenetic model of circula-tion and drawing of Late Cretaceous geothermal waters for the fluorite deposits in southeastern China. Thismodel includes two types of mechanism: 1) the leaching-out and drawing through deep circulation of thegeothermal water, and 2) the leaching-out and drawing through shallow circulation of the water. The fluoritemineralization of Mesozoic volcanic rock terrain is related mainly to the former mechanism, with the mineraliz-ing material coming chiefly from the Precambrian metamorphic rocks of the basement underlying the hostrocks; while that of Yanshanian granite terrain is associated with the latter mechanism, with the mineralizingmaterial derived primarily from the host granites and sedimentary rocks.

关键词： Minerogenetic Model for Two Types of Fluorite Deposits in Southeastern China

Modified calcination conditions of rare alkali metal Rb-containing muscovite(KAl_2[AlSi_3O_(10)](OH)_2)

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Rare Metals 2013年第6期32卷 632-635页

作者： Zhi-Qiang Shan Xin-Qian Shu Ji-Fu Feng Wei-Ning Zhou School of Chemical and Environmental engineering China University of Mining & Technology Comprehensive Utilization Research institute of Resource Guilin Research Institute Geology for Mineral Resources

Muscovite mineral was roasted in different *** leaching rate was a standard to examine the impact of various factors on calcination effect,including the agent types,roasting time,mass ratio,and roasting *** results indicate that the best agent is the combination of sodium chloride and calcium chloride,and its mass ratio of muscovite/NaCl/CaCl2is1.00:0.25:*** at 850℃ for 30 min,the rubidium leaching rate is up to 90.12%.The reaction of muscovite ore with the chlorinating agent CaCl2was studied by TG/DSC,and the surface morphology before and after leaching was characterized by *** chloride products can be obtained using t-BAMBP extraction,hydrochloric acid re-extraction,and purification.

关键词： Modified calcination Muscovite ore Chlorinating agent

Zircon U-Pb Age, Geochemistry and Geological Implication of the 255 Ma Alkali-Rich Dykes from Ulungur Area, North Xinjiang

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Journal of Earth Science 2013年第4期24卷 519-528页

作者：陈言飞王玉往王京彬丁汝福袁月蕾石煜 School of Gemmology China University of Geosciences Beijing institute ofGeology for mineral Resources Beijing institute of Geology for mineral Resources School of Earth Sciences and mineral Resources China University of Geosciences

Alkali-rich dykes of the Late Permian in Ulungur （乌伦古） area are representative prod- ucts of granitic magmatism in the evolution of the Paleozoic orogenic belt in the East Junggar （准噶尔）, North Xinjiang （新疆）. We selected two representative samples for geochemical analysis （major and trace elements）, and twenty-two zircon grains for zircon dating. Isoplot （ver3.0） was used to calculate isotopic age and make concordia diagrams. This study shows that the trachy porphyry dykes, featuring low concentration of A1203, CaO, MgO and high alkali contents, are metaluminous alkaline rock and belong to A-type granitoids. The dykes have low concentration of the REE and incompatible elements, and the REE patterns show clear negative Eu anomalies （6Eu=0.74-0.58）, enriched LREE （LREE/HREE〉4, （La/Yb）N=5.97-4.63） and undifferentiated HREEs. Similar normalized REE and in- compatible element patterns are also showed in the dykes from Yemaquan （野马泉） and granites from Ulungur, suggesting that they are possibly originated from the same source and formed in the same tectonic environment, but the trachy porphyry dykes are more evolved. The age of the trachy porphyry dykes is 255.3 - 2.4 Ma, which is probably the crystallization time of the trachy porphyry. The dykes formed in late-orogenic phase of post-collision process or within-plate environment, which suggested that the trachy porphyry dykes possibly crystallized in the transition period during which the tectonic setting changed from post-collision to with- in-plate environment. So we consider that the age when the post-collision ended and the crustal cratonization begun in the East Junggar is 255 Ma, Late Permian.

关键词： Ulungur alkali-rich dyke zircon U-Pb age petrology and geochemistry tectonic setting post-collision.

An analysis of contributing mining factors in coal workers’pneumoconiosis prevalence in the United States coal mines,1986-2018

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International Journal of Coal Science & Technology 2021年第6期8卷 1227-1237页

作者： Younes Shekarian Elham Rahimi Naser Shekarian Mohammad Rezaee Pedram Roghanchi Department of mineral engineering New Mexico Institute of Mining and TechnologySocorroNMUSA Department of Information Systems Business SchoolUniversity of Colorado DenverDenverCOUSA John and Willie Leone Family Department of Energy and mineral engineering Earth and Mineral Sciences(EMS)Energy InstituteThe Pennsylvania State UniversityUniversity ParkPAUSA

In the United States,an unexpected and severe increase in coal miners’lung diseases in the late 1990s prompted researchers to investigate the causes of the disease *** study aims to scrutinize the effects of various mining parameters,including coal rank,mine size,mine operation type,coal seam height,and geographical location on the prevalence of coal worker’s pneumoconiosis(CWP)in surface and underground coal mines.A comprehensive dataset was created using the *** Safety and Health Administration(MSHA)Employment and Accident/Injury *** information was merged based on the mine ID by utilizing SQL data management software.A total number of 123,589 mine-year observations were included in the statistical *** Estimating Equation(GEE)model was used to conduct a statistical analysis on a total of 29,707,and 32,643 mine-year observations for underground and surface coal mines,*** results of the econometrics approach revealed that coal workers in underground coal mines are at a greater risk of CWP comparing to those of surface coal ***,underground coal mines in the Appalachia and Interior regions are at a higher risk of CWP prevalence than the Western *** coal mines in the Appalachian coal region are more likely to CWP development than miners in the Western *** analysis also indicated that coal workers working in smaller mines are more vulnerable to CWP than those in large mine ***,coal workers in thin-seam underground mine operations are more likely to develop CWP.

关键词： Respirable coal mine dust Respiratory diseases Coal worker’s pneumoconiosis(CWP) Occupational exposure

Microwave-assisted reduction roasting–magnetic separation studies of two mineralogically different low-grade iron ores

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International Journal of minerals,Metallurgy and Materials 2020年第11期27卷 1449-1461页

作者： Subhnit K.Roy Deepak Nayak Nilima Dash Nikhil Dhawan Swagat S.Rath mineral Processing Department CSIR-Institute of Minerals and Materials TechnologyBhubaneswar 751013India Department of Metallurgical and Materials engineering Indian Institute of TechnologyRoorkee 247667India

The microwave-assisted reduction behaviours of two low-grade iron ores having a similar Fe content of 49wt%but distinctly different mineralogical and liberation characteristics were *** performances in terms of the iron grade and recovery as obtained from statistically designed microwave(MW)roasting followed by low-intensity magnetic separation(LIMS)experiments were *** respective optimum conditions,the titano-magnetite ore(O1)could yield an iron concentrate of 62.57%Fe grade and 60.01%Fe recovery,while the goethitic ore(O2)could be upgraded to a concentrate of 64.4%Fe grade and 33.3%Fe *** with the goethitic ore,the titanomagnetite ore responded better to MW *** characterization studies of the feed and roasted products obtained at different power and time conditions using X-ray diffraction,optical microscopy,vibrating-sample magnetometry,and electron-probe microanalysis explain the sequential reduction in the iron oxide ***,taking advantage of the MW absorbing character of the titano-magnetite ore,a blend of the same with the goethite-rich ore at a weight ratio of 60:40(O2:O1)was subjected to MW roasting that resulted in a concentrate of 61.57%Fe grade with a Fe recovery of 64.47%.

关键词： microwave reduction roasting titano-magnetite ore goethitic ore magnetic separation

Characteristics and evolution of ore-forming fluids of the Chongjiang copper deposit in the Gangdise porphyry copper belt, Tibet

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Journal of University of Science and Technology Beijing 2007年第2期14卷 97-102页

作者： Yuling Xie Jiuhua Xu Guangming Li Zhiming Yang Longsheng Yi Civil and Environmental engineering School University of Science and Technology Beijing Beijing 100083 China Chengdu institute of Geology and mineral Resource Ministry of Land and Resource Chengdu 610082 China institute of mineral Resources China Academy of Geological Science Beijing 100037 China

Petrography, microthermometry, and scanning electron microscope/energy dispersive spectrometer （SEM/EDS） studies were performed on the fluid inclusions in the ore-beating quartz veins and quartz phenocrysts in the porphyry of the Chongjiang porphyry copper deposit. The analyses of the fluid inclusions indicate that the ore-forming fluids were exsolved from magma. They are near-saturated, supercritical, rich in volatile constituents, and have the capture temperature of 362-389℃ and salinities of 17.7wt%- 18.9wt% NaC1 eq. With the decreasing of temperature and pressure, the supercritical fluids were separated into a low salinity vapor phase and a high salinity liquid phase. During quartz-sericitization, the high salinity fluid boiled and separated into a low salinity vapor phase and a high salinity liquid phase. The high salinity inclusions that formed in the boiling process had daughter mineral melting temperatures higher than the homogenization temperatures of the vapor and liquid phases. The late fluids that are responsible for argillization are of lower temperature and salinity.

关键词： Gangdise porphyry copper belt Chongjiang copper deposit fluid inclusions ore-forming fluids

Effect of sodium alginate on reverse flotation of hematite and its mechanism

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International Journal of minerals,Metallurgy and Materials 2018年第10期25卷 1113-1122页

作者： Ya-feng Fu Wan-zhong Yin Bin Yang Chuang Li Zhang-lei Zhu Dong Li School of Resources & Civil engineering Northeastern University The State Key Laboratory of mineral Processing Beijing General Research Institute of Mining & Metallurgy

Given the gradual increase in the chlorite content of hematite ores, pulp properties seriously deteriorate during flotation. The traditional anion reverse flotation of hematite cannot effectively eliminate the effects of chlorite, leading to a significant decrease in the total Fe(TFe) grade of the concentrate. In this work, the effect of sodium alginate on the reverse flotation of hematite was systematically investigated. Flotation tests of artificially mixed ores were conducted, and the results showed that sodium alginate can significantly improve the removal rates of quartz and chlorite. The adsorption measurements, infrared spectroscopy, and contact angle tests demonstrated that sodium alginate adsorbs on the quartz surface by chelating with calcium ions, thereby weakening the steric hindrance of oleate ions and increasing the adsorption capacity of sodium oleate to ultimately improve the removal rate of quartz. Furthermore, owing to its lower density and fine particle size, chlorite is easily entrained into the foam layer. Sodium alginate dramatically increases the liquid-to-gas ratio of the foam layer by increasing pulp viscosity, thereby increasing the entrainment rate of chlorite and finally improving its removal rate. The core content of this thesis bears significance in improving the Fe grade in the reverse flotation of chlorite-containing hematite.

关键词： hematite reverse flotation sodium alginate pulp viscosity entrainment rate

A new hybrid decision support tool for evaluating the sustainability of mining projects

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International Journal of Mining Science and Technology 2018年第2期28卷 259-265页

作者： Kamenopoulos S. Agioutantis Z. Komnitsas K. School of mineral Resources engineering Technical University of Crete Department of Mining engineering University of Kentucky

The integration of sustainable development challenges and opportunities into the decision making process during the design and/or implementation of multi-disciplinary mining projects is generally not supported by decision support systems(DSS). A new hybrid decision support tool, which features an integrated assessment of sustainable development issues as they apply to mining projects, is hereby proposed. The proposed DSS framework, named ‘‘Acropolis DSS", can be used to assist involved stakeholders in critical decisions, especially when addressing issues such as stakeholder participation, transparency,and trade-offs. The proposed DSS is based on a multi-criteria decision analysis combined with the multi-attribute utility theory.

关键词： Sustainable development Multi-criteria decision analysis Indicators Stakeholders Rare earth elements

Hierarchically porous carbon derived from natural Porphyra for excellent electromagnetic wave absorption

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Journal of Materials Science & Technology 2022年第34期129卷 206-214页

作者： Juhua Luo Ziyang Dai Mengna Feng Xiaowen Chen Caihong Sun Ying Xu School of Materials Science and engineering Yancheng Institute of TechnologyYancheng 224051China National and Local Joint engineering Research Center for mineral Salt Deep Utilization Huaiyin Institute of TechnologyHuaiyin 223003China

A highly efficient absorber with features including lightweight, broad bandwidth, and tunable electromagnetic property still remains challenging for practical applications. Herein, the Porphyra-derived porous carbon(PPC) was fabricated via facile procedures of low-temperature pre-carbonization combined with KOH chemical activation. The composition, microstructure, and electromagnetic wave absorption properties of the samples were elucidated based on X-ray diffraction(XRD), Raman, X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), transmission electron microscopy(TEM),Brunauer-Emmer-Teller(BET), and vector network analyzer(VNA). The porosity of PPC can be readily regulated by adjusting activation temperature. The PPC obtained at 750 ℃ was composed of a threedimensional hierarchically porous carbon network. The C and N elements of natural Porphyra were introduced into the carbon skeleton during the carbonization process. The large specific surface, dopants, and three-dimensional hierarchically porous carbon network can effectively improve the impedance matching and dielectric dissipation, leading to an excellent electromagnetic wave absorption performance. Especially, the optimal reflection loss(RL) value reached –57.75 d B at 9.68 GHz with a broad bandwidth(RL< –10 d B) value of 7.60 GHz at 3.5 mm. Overall, the results indicate that the PPC can provide a new way to achieve lightweight, effective, and sustainable absorbers.

关键词： Porphyra-derived carbon Hierarchically porosity Electromagnetic wave absorption Broad bandwidth Lightweight