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Ground subsidence mechanism of a filling mine with a steeply inclined ore body
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作者 LI Guang LIU Shuai-qi +2 位作者 MA Feng-shan GUO Jie HUI Xin 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2358-2369,共12页
Long-term field monitoring finds that serious surface subsidence can still occur even if the high strength cemented fill method is adopted.Combining the results of numerical simulations with global position system(GPS... Long-term field monitoring finds that serious surface subsidence can still occur even if the high strength cemented fill method is adopted.Combining the results of numerical simulations with global position system(GPS)monitoring,we took a typical filling mining mine with a steeply inclined ore body as an example,and explored its ground subsidence mechanism.The results show that the ground subsidence caused by the mining of steep ore body is characterized by two settlement centers and a significantly uneven spatial distribution,which is visibly different from ground subsidence characteristic of the coal mine.The subsidence on the hanging wall is much larger than that on the footwall,and the settlement center tends to move to the hanging wall with the increase of mining depth.The backfill improves the strength and surrounding rock bearing capacity,which leads to a lag of about 3 years of the subsidence.However,under the actions of continuous and repeated mining disturbances,the supporting effect of the backfill can only reduce the amplitude of the deformation,but it cannot prevent the occurrence of settlement. 展开更多
关键词 Ground subsidence Backfill mining Steeply inclined ore body GPS monitoring Rock mass movement model
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Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)
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作者 Rania Ben Aissa Wiem Ben Aissa +2 位作者 Said Tlig Lassaad Ben Aissa Abdessalem Ben Haj Amara 《Acta Geochimica》 EI CAS CSCD 2024年第2期366-384,共19页
The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization ... The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary. 展开更多
关键词 ore-formingfluids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey ore deposit North Tunisia
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Geochemical Characteristics,Genesis of Concealed Cu-rich Ore Body in the Jinchuan Deposit,Northwestern China,and Its Prospecting 被引量:9
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作者 GAO Yalin TANG Zhongli +2 位作者 ZHANG Mingjie TIAN Yulong XIAO Lizhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第6期1085-1100,共16页
The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and ... The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and the border of the deposit becomes more and more important. The ore body, ore and geochemistry characteristics of the concealed Cu-rich ore body are researched. Through spatial analysis and comparison with the neighboring II1 main ore body, the mineralization rule of the concealed Cu-rich ore body is summed up. It is also implied that Cu-rich magma may exist between Nirich magma and ore pulp during liquation differentiation in deep-stage chambers, which derives from deep-mantle Hi-MgO basalt magma. It is concluded that the type of ore body has features of both magmatic liquation and late reconstruction action. It has experienced three stages: deep liquation and pulsatory injection of the Cu- and PPGE-rich magma, concentration of tectonic activation, and the later magma hydrothermal superimposition. In addition, the Pb and S isotopes indicate the magma of I6 concealed Cu-rich ore body originates predominantly from mantle; however, it is interfused by minute crust material. Finally, it is inferred that the genesis of the Cu-Ni sulfide deposit is complex and diverse, and the prospect of seeking new deep ore bodies within similar deposits is promising, especially Cu-rich ore bodies. 展开更多
关键词 Cu-Ni sulfide deposit Cu-rich magma Cu-rich ore body PROSPECTING Jinchuan
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Application of Tectono Geochemical Study in Deep Concealed Ore Body Exploration--As the Huize Super-Large Lead-Zinc Deposit an exemple 被引量:1
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作者 ZHANG Quan GUO Yuxinyue +1 位作者 PU Chuanjie WANG Feng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期247-248,共2页
1 Geological Background of Minerlization or Geologic Setting The northeast of Yunnan1 Pb-Zn-Ag-Ge polymetallic ore district is an important part of the southwestern margin of the Yangtze block Sichuan-Yunnan-Guizhou
关键词 Application of Tectono Geochemical Study in Deep Concealed ore body Exploration NE As the Huize Super-Large Lead-Zinc Deposit an exemple MVT
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Lithium extraction from hard rock lithium ores(spodumene,lepidolite,zinnwaldite,petalite):Technology,resources,environment and cost 被引量:5
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作者 Tian-ming Gao Na Fan +1 位作者 Wu Chen Tao Dai 《China Geology》 CAS CSCD 2023年第1期137-153,共17页
Lithium production in China mainly depends on hard rock lithium ores,which has a defect in resources,environment,and economy compared with extracting lithium from brine.This paper focuses on the research progress of e... Lithium production in China mainly depends on hard rock lithium ores,which has a defect in resources,environment,and economy compared with extracting lithium from brine.This paper focuses on the research progress of extracting lithium from spodumene,lepidolite,petalite,and zinnwaldite by acid,alkali,salt roasting,and chlorination methods,and analyzes the resource intensity,environmental impact,and production cost of industrial lithium extraction from spodumene and lepidolite.It is found that the sulfuric acid method has a high lithium recovery rate,but with a complicated process and high energy consumption;alkali and chlorination methods can directly react with lithium ores,reducing energy consumption,but need to optimize reaction conditions and safety of equipment and operation;the salt roasting method has large material flux and high energy consumption,so require adjustment of sulfate ratio to increase the lithium yield and reduce production cost.Compared with extracting lithium from brine,extracting lithium from ores,calcination,roasting,purity,and other processes consume more resources and energy;and its environmental impact mainly comes from the pollutants discharged by fossil energy,9.3-60.4 times that of lithium extracted from brine.The processing cost of lithium extraction from lepidolite by sulfate roasting method is higher than that from spodumene by sulfuric acid due to the consumption of high-value sulfate.However,the production costs of both are mainly affected by the price of lithium ores,which is less competitive than that of extracting lithium from brine.Thus,the process of extracting lithium from ores should develop appropriate technology,shorten the process flow,save resources and energy,and increase the recovery rate of related elements to reduce environmental impact and improve the added value of by-products and the economy of the process. 展开更多
关键词 Lithium ore Lithium extraction Comprehensive utilization Acid method Alkali method Salt roasting method Chlorination method Mineral exploration engineering
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Forecast of blind ore body in Zhangcaigou area around Wulaga gold deposit
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作者 Guoxue Wu Guohua Chen Zhigang Lü 《Global Geology》 2006年第1期13-18,共6页
By the study of metallogenetic conditions and ore-controlling factors, the metallogenetic indicators in geology, geochemistry and geophysics about Wulaga gold deposit have been obtained. Using the indicators the blind... By the study of metallogenetic conditions and ore-controlling factors, the metallogenetic indicators in geology, geochemistry and geophysics about Wulaga gold deposit have been obtained. Using the indicators the blind ore bodies have been forecasted in Zhangcaigou area. By drilling check, a gold-bearing ore body with 3 m thickness in an average tenor of 20.4×10 -6 at the depth of 70 m has been found in the forecast area. It shows that the forecast method should be effective. 展开更多
关键词 Wulaga gold deposit blind ore body mineral forecast
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Geological Characteristics and Regional Prospecting Model of Wulanchongji Gold Orebody, Alxa Youqi, Inner Mongolia, China
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作者 Yonghui Su Yang Liu +1 位作者 Chao Li Shuai Zhao 《International Journal of Geosciences》 2021年第4期431-438,共8页
Five gold deposits (mineralization) were found in the study area by means of geologi</span><span style="font-family:Verdana;">cal mapping, soil geochemical survey and trough exploration engineeri... Five gold deposits (mineralization) were found in the study area by means of geologi</span><span style="font-family:Verdana;">cal mapping, soil geochemical survey and trough exploration engineering. The</span><span style="font-family:Verdana;"> ore-bearing lithology is mainly metam</span></span><span style="font-family:Verdana;">orphic feldspar sandstone of </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">Upper Carboniferous Benbatu Formation, and the gold (mineralization) body is controlled by both structural factors </span><span style="font-family:Verdana;">and stratigraphic factors of </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">Upper Carboniferous Benbatu Formation. The genetic</span><span style="font-family:""><span style="font-family:Verdana;"> type is preliminary concluded to be volcanic hyd</span><span style="color:black;font-family:Verdana;">rothermal type, and the metallogenic age is late Variscan. In this paper, by studying the geological characteristics and metallogenic geological conditions of the gold orebody in the area, a regional prospecting model has been established, which is of great significance to better guide the prospecting work of similar gold deposits in the area and the region. 展开更多
关键词 Gold ore Hydrothermal Solution Genesis of Mineral Deposit Prospecting Model Benbatu Formation
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Diversity and Adaptations of Immature Diptera in Semiaquatic Habitats at Shorelines of Hypersaline Lakes in the Crimea,with a Brief Review of Diptera in Mineralized Bodies of Water
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作者 Andrey PRZHIBORO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期98-100,共3页
The order Diptera(Insecta)is one of animal groups most successful in the colonization of mineralized shallow aquatic and semiaquatic environments.At the same time,the taxonomic composition of Diptera,their role in
关键词 salt lakes mineralized bodies of water aquatic habitats shoreline semiaquatic habitats Diptera larvae biodiversity community taxonomic richness adaptations heat shock proteins.
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Study on Epithermal Gold Mineralization System at Shwebontha Prospect,Monywa Copper-Gold Ore Field,Central Myanmar
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作者 Toe Naing Oo Agung Harijoko Lucas Donny Setijadji 《Advances in Geological and Geotechnical Engineering Research》 2023年第1期10-23,共14页
The Shwebontha prospect area is situated in the Central Volcanic Belt,central Myanmar,where the well-known Sagaing Fault serves as its eastern boundary.This study aims to document key the mineralogy,host rock geochemi... The Shwebontha prospect area is situated in the Central Volcanic Belt,central Myanmar,where the well-known Sagaing Fault serves as its eastern boundary.This study aims to document key the mineralogy,host rock geochemistry and ore mineralizing fluids.The mineralization,hosted by Upper Oligocene to Middle Miocene rhyolites,displays a strong lithological control.Mineralization is characterized by gold-bearing silicified massive ore and chalcedonic quartz veins in which sulfides are clustered and disseminated not only in quartz gangue but also in rhyolite host rocks.The significant ore minerals in the mineralized veins include pyrite,sphalerite,galena,chalcopyrite,and gold.Common hydrothermal alterations such as silicic,argillic and propylitic alteration types are recognized.According to the fluid inclusion data and interpretation,ore mineralizing fluids in the research area are characterized by formation temperatures of 260-280℃ and salinity of 0.35-2.41%wt.NaCl eq.respectively.Mixing of hydrothermal fluids was generally considered to be an effective mechanism for ore transport and deposition. 展开更多
关键词 Geochemistry ALTERATION Fluid inclusions ore mineralization Central Volcanic Belt Shwebontha
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贵东复式岩体中东部晚期花岗质小岩体的SHRIMP锆石U-Pb年龄及其地质意义
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作者 吴佳 巫建华 +2 位作者 刘晓东 王凯兴 刘帅 《高校地质学报》 CAS CSCD 北大核心 2024年第1期56-71,共16页
贵东复式岩体由多期次、多类型的岩体组成,且东部盛产铀矿床,因此精确厘定该复式岩体的时代及其时序,查明复式岩体东部与中西部岩浆活动的差异性及其与铀成矿的关系,不仅有利于深入研究区域岩浆活动,而且有利于深刻认识铀的成矿规律。... 贵东复式岩体由多期次、多类型的岩体组成,且东部盛产铀矿床,因此精确厘定该复式岩体的时代及其时序,查明复式岩体东部与中西部岩浆活动的差异性及其与铀成矿的关系,不仅有利于深入研究区域岩浆活动,而且有利于深刻认识铀的成矿规律。现有研究认为,以龟尾山断裂带为界,贵东复式岩体中西部岩基属燕山早期、东部岩基属印支早期,东部广泛发育的燕山期中基性脉岩与铀成矿关系密切。但对复式岩体中东部呈岩枝、岩株广泛出露的晚期花岗质小岩体的成岩地质时代及其分布规律尚存在争议,也有待进一步查明花岗质小岩体与铀矿床的时空关系。文章选择贵东复式岩体中东部晚期花岗质小岩体为研究对象,采用SHRIMP锆石U-Pb法厘定其成岩时代,并分析它们的时空分布及其与铀成矿的关系。测试结果显示,贵东复式岩体中东部晚期花岗质小岩体普遍存在高铀锆石,这可能是对同一岩体不同学者所获得的^(206)Pb/^(238)U加权平均年龄差别较大的主要原因。剔除高铀锆石的年龄数据,龟尾山断裂带以西的隘子、司前、陈洞岩体锆石^(206)Pb/^(238)U加权平均年龄分别为163.0±1.6 Ma、163.1±1.6 Ma、160.7±1.9 Ma,属燕山早期岩浆活动的产物;而以东的帽峰、分水坳、龟尾山岩体锆石^(206)Pb/^(238)U加权平均年龄分别为230.0±2.7 Ma、225.9±2.9 Ma和232.6±3.1 Ma,属印支期岩浆活动的产物。所以,龟尾山断裂以西和以东晚期花岗质小岩体的时代不同。且龟尾山断裂带以东的印支期花岗质小岩体空间上与铀矿化、尤其是与燕山早期的绢英岩化型等中高温热液铀矿化关系密切,是主要的储矿围岩;结合元素地球化学研究结果,该区产出的印支期花岗质小岩体也可为铀成矿提供铀源。 展开更多
关键词 贵东复式岩体 花岗质小岩体 SHRIMP锆石U-PB年龄 铀成矿
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氧化石墨烯辅助仿生矿化原位合成羟基磷灰石
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作者 张彪 石淇铭 +5 位作者 白梓恒 刘泓宇 马涛 王芬 朱建锋 施佩 《硅酸盐通报》 CAS 北大核心 2024年第1期363-369,共7页
羟基磷灰石(HAp)是一种与人体骨骼成分类似的无机材料,具有良好的生物相容性。本文以氧化石墨烯(GO)为模板,通过模拟体液(SBF)仿生矿化原位合成了HAp纳米粒子。通过SEM、XRD、EDS和拉曼光谱等测试分析研究了矿化时间、SBF/GO体积比对矿... 羟基磷灰石(HAp)是一种与人体骨骼成分类似的无机材料,具有良好的生物相容性。本文以氧化石墨烯(GO)为模板,通过模拟体液(SBF)仿生矿化原位合成了HAp纳米粒子。通过SEM、XRD、EDS和拉曼光谱等测试分析研究了矿化时间、SBF/GO体积比对矿化产物物相组成、形貌和结构的影响。结果表明,矿化处理后的GO表面形成了大量均匀分布的类骨HAp。随着矿化时间延长和SBF体积占比增大,矿化产物的尺寸及数量增大,GO层间距逐渐扩大。本研究验证了GO辅助合成HAp的可行性,拓展了仿生矿化法的应用领域。 展开更多
关键词 仿生矿化 氧化石墨烯 羟基磷灰石 模拟体液 原位合成 粒径变化
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肌少症病人超声参数与体质指数、骨密度及骨骼肌质量指数的关系
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作者 岳一婷 李红梅 +3 位作者 薛晓燕 郭锦丽 张蕊 陈梦坤 《护理研究》 北大核心 2024年第11期1914-1918,共5页
目的:探究肌少症病人超声参数与体质指数、骨密度及骨骼肌质量指数的关系。方法:选取山西医科大学第二医院2023年1月1日—2024年1月1日收治的60例肌少症病人为研究组,选取同期来院体检的50名性别、年龄匹配的健康志愿者为对照组。两组... 目的:探究肌少症病人超声参数与体质指数、骨密度及骨骼肌质量指数的关系。方法:选取山西医科大学第二医院2023年1月1日—2024年1月1日收治的60例肌少症病人为研究组,选取同期来院体检的50名性别、年龄匹配的健康志愿者为对照组。两组均接受超声检查,记录腓肠肌肌肉厚度、肌肉最大横截面积、肌肉硬度(收缩及舒张时杨氏模量值)及双能X线吸收法检查,记录骨密度、四肢肌肉量并计算骨骼肌质量指数及体质指数。对比两组上述指标差异,使用Logistic回归分析筛选肌少症影响因素,使用受试者工作特征(ROC)曲线分析超声参数对肌少症诊断效能,使用Pearson相关系数分析研究组超声参数与体质指数、骨密度及骨骼肌质量指数的相关性。结果:Logistic回归分析结果显示:腓肠肌肌肉厚度、肌肉最大横截面积、收缩及舒张时杨氏模量值、体质指数、骨密度及骨骼肌质量指数是肌少症的独立影响因素(P<0.05);腓肠肌肌肉厚度、肌肉最大横截面积、收缩、舒张时杨氏模量值诊断肌少症ROC曲线下面积分别为0.908,0.958,0.909,0.932;Pearson相关分析结果显示,肌少症病人腓肠肌肌肉厚度、肌肉最大横截面积、收缩及舒张时杨氏模量值与体质指数、骨密度及骨骼肌质量指数均呈正相关(P<0.05)。结论:超声参数有助于筛查诊断肌少症,超声参数、腓肠肌肌肉厚度、肌肉最大横截面积、肌肉硬度与体质指数、骨密度及骨骼肌质量指数存在明显关联。 展开更多
关键词 肌少症 超声 体质指数 骨密度 骨骼肌质量指数 肌肉硬度
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松辽盆地南部砂岩型铀矿储层结构与铀成矿作用
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作者 翁海蛟 张韶华 +3 位作者 刘鑫 臧亚辉 贺航航 卢天军 《地质通报》 CAS CSCD 北大核心 2024年第1期117-130,共14页
以松辽盆地南部DL地区砂岩型铀矿为目标,在沉积学背景研究的基础上,开展铀储层结构与铀成矿作用研究。通过钻孔数据统计及系统的取样分析并编制铀储层非均质性图件,精细地刻画了姚家组铀储层的几何形态和复杂结构,充分展示了铀储层的定... 以松辽盆地南部DL地区砂岩型铀矿为目标,在沉积学背景研究的基础上,开展铀储层结构与铀成矿作用研究。通过钻孔数据统计及系统的取样分析并编制铀储层非均质性图件,精细地刻画了姚家组铀储层的几何形态和复杂结构,充分展示了铀储层的定量非均质性。结果显示,区内灰色砂体多为原生灰色砂体,而下氧化带在沉积期后经历了较强的表生流体改造,为后生氧化带,矿体主要分布于河道砂体分岔处,以及从无隔挡层到隔挡层突然变厚的河道砂体边缘而非河道中央,其形态受氧化还原界面控制以板状为主。综合分析认为,表生流体成矿作用经历了晚白垩世姚家组含矿主岩预富集与表生流体叠加改造成矿2个阶段。通过对比DL地区储层结构对铀成矿的控制作用,在BL地区优选出3片找矿靶区,为下一步的勘查工作提供理论依据。 展开更多
关键词 砂岩型铀矿储层 砂体非均质性 表生流体成矿作用 姚家组 找矿预测 松辽盆地
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肥胖和骨质疏松之间的关联:一项两样本双向孟德尔随机化分析
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作者 詹群璋 张钰玲 +3 位作者 韩雨欣 吕嘉振 郑晓霞 曲崇正 《中国组织工程研究》 CAS 北大核心 2024年第27期4319-4324,共6页
背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据... 背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据来自人体特征遗传调查(GIANT)和英国生物样本库(UKBB)的汇总统计数据。骨质疏松症的数据来自从骨质疏松症遗传因素联盟(GeFOS)获得的2种骨密度表型:全身骨密度和跟骨骨密度。逆方差加权法为主要分析方法,基于Egger回归的孟德尔随机化法(Mendelian randomization method based on Egger regression,MR-Egger)和加权中位数法作为补充方法来计算肥胖遗传变异与骨质疏松症之间的因果关联。采用敏感性分析来验证结果的可靠性,利用Cochran’s Q检验分析结果的异质性,利用MR-Egger截距检验分析结果的水平多效性,留一法评估合并的逆方差加权法估计值是否具有潜在影响的单核苷酸多态性。结果与结论:①肥胖对骨质疏松症的影响:除身体质量指数与前臂骨密度外,身体质量指数、腰臀比、经身体质量指数调整的腰臀比与全身骨密度、跟骨骨密度、前臂骨密度、腰椎骨密度及股骨颈骨密度两两之间呈正向因果关系;进一步Meta分析显示,肥胖会增加骨密度的风险(OR=1.08,95%CI:1.05-1.11,P<0.01);②骨质疏松症对肥胖的影响:除了前臂骨密度、腰椎骨密度作为暴露因素对肥胖有因果关系外,其他数据集均显示全身骨密度、跟骨骨密度、股骨颈骨密度与肥胖之间不呈现因果效应;进一步Meta分析显示,骨密度并不会增加肥胖的风险(OR=0.99,95%CI:0.98-1.01,P<0.01)。③结果证实:肥胖与骨质疏松之间存在因果关系,即肥胖可能是骨质疏松症的危险性因素,但未发现骨质疏松症对于肥胖的因果关联。 展开更多
关键词 肥胖 骨质疏松症 孟德尔随机化 因果关系 骨密度 Meta分析 身体质量指数
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绝经后女性不同部位骨密度及FRAX预测值与BMI的相关性分析
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作者 吴婉 郦忆文 +3 位作者 梁冰 王旸 曹玉茹 王涛 《蚌埠医学院学报》 CAS 2024年第2期182-186,共5页
目的:探讨绝经后女性不同部位骨密度(BMD)及骨折风险评估工具(FRAX)计算出的骨折风险与体质量指数(BMI)的相关性。方法:选取2020年9月至2021年8月于蚌埠医科大学第一附属医院就诊并进行BMD检查的绝经后女性313例,收集研究对象的人口统... 目的:探讨绝经后女性不同部位骨密度(BMD)及骨折风险评估工具(FRAX)计算出的骨折风险与体质量指数(BMI)的相关性。方法:选取2020年9月至2021年8月于蚌埠医科大学第一附属医院就诊并进行BMD检查的绝经后女性313例,收集研究对象的人口统计学资料及BMD相关信息,并应用FRAX工具计算未来10年发生主要骨质疏松性骨折(脊椎、前臂、髋骨或肩部骨折)的概率(PMOF)和髋部骨折的概率(PHF),分析FRAX预测值与BMD和BMI的相关性,以及联合股骨颈T值的FRAX预测值和不联合股骨颈T值的FRAX预测值是否有差异。结果:腰椎、股骨颈、全髋的BMD随着BMI的增加而增加(P<0.01);FRAX预测值在联合股骨颈T值的情况下,随着BMI的增加,骨折风险逐渐下降(P<0.01);未联合股骨颈T值的FRAX预测值在BMI<28 kg/m^(2)时,随着BMI的增加,骨折风险逐渐下降(P<0.05),当BMI≥28 kg/m^(2)时,骨折风险开始出现上升趋势(P<0.05);在骨量减少人群中,难以筛选出骨折高危人群,FRAX严重低估了发生主要骨质疏松性骨折的风险。结论:体质量过低的人群BMD通常较低,使用FRAX评估其发生骨折的风险相对较高。 展开更多
关键词 骨质疏松性骨折 绝经 女性 体质量指数 骨折风险评估工具 骨密度
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女性年龄与骨密度、骨质疏松的关系及发生骨质疏松的影响因素分析
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作者 陈伟银 李瑞莉 黄汉超 《中国实用医药》 2024年第1期60-63,共4页
目的分析女性年龄与骨密度、骨质疏松的关系及发生骨质疏松的影响因素。方法215例女性健康体检者,按不同年龄段划分,≤44岁为青年组(59例)、45~59岁为中年组(94例)、≥60岁为老年组(62例)。比较三组受试者腰椎1~4及股骨颈骨密度、骨质... 目的分析女性年龄与骨密度、骨质疏松的关系及发生骨质疏松的影响因素。方法215例女性健康体检者,按不同年龄段划分,≤44岁为青年组(59例)、45~59岁为中年组(94例)、≥60岁为老年组(62例)。比较三组受试者腰椎1~4及股骨颈骨密度、骨质疏松发生情况,并比较发生与未发生骨质疏松受试者的基本临床资料{受教育程度、体质量指数(BMI)、酗酒、家族骨质疏松史、血清25-羟基维生素D[25(OH)D]水平、四肢骨骼肌指数(ASMI)、幽门螺杆菌(Hp)感染、匹兹堡睡眠质量指数(PSQI)},采用Logistic回归分析女性骨质疏松的影响因素。结果老年组腰椎1~4骨密度(0.95±0.10)g/cm^(2)及股骨颈骨密度(0.76±0.08)g/cm^(2)明显低于中年组的(1.04±0.13)、(0.93±0.10)g/cm^(2)、青年组的(1.09±0.16)、(1.02±0.12)g/cm^(2),且中年组低于青年组,差异有统计学意义(P<0.05)。215例受试者中,有31例发生骨质疏松,占比14.42%,其中老年组骨质疏松发生率30.65%(19/62)明显高于青年组的6.78%(4/59)、中年组的8.51%(8/94),差异有统计学意义(χ^(2)=18.678,P<0.05)。发生骨质疏松女性的BMI(21.88±1.39)kg/m^(2)、血清25(OH)D水平(13.59±1.45)mmol/L、ASMI(5.36±0.58)kg/m^(2)低于未发生骨质疏松的(23.86±1.17)kg/m^(2)、(16.24±1.71)mmol/L、(6.41±0.72)kg/m^(2),发生骨质疏松女性的Hp感染占比83.87%高于未发生骨质疏松的59.78%,差异有统计学意义(P<0.05);发生与未发生骨质疏松的女性受教育程度、酗酒、家族骨质疏松史、PSQI评分比较,差异无统计学意义(P>0.05)。经Logistic回归分析显示,Hp感染是女性发生骨质疏松的危险因素(OR>1,P<0.05),高BMI、血清25(OH)D水平、ASMI水平均是女性发生骨质疏松的保护因素(OR<1,P<0.05)。结论老年阶段女性骨密度较低,骨质疏松发生风险较高,且BMI、血清25(OH)D水平、ASMI、Hp感染是女性发生骨质疏松的影响因素,临床可据此提出具有针对性、科学合理的干预措施以减少女性骨质疏松的发生。 展开更多
关键词 骨密度 骨质疏松 体质量指数 25-羟基维生素D 幽门螺杆菌感染
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平行断面法客观计算矿体体积参数的新方法
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作者 李海光 郭有录 +2 位作者 史建儒 段睿 陈鹏 《矿产勘查》 2024年第3期449-454,共6页
在现行固体矿产资源量估算规程(DZ/T 0338.2-2020)第2部分几何法中,其对平行断面块段矿体体积参数的计算采用的是传统的模拟断面形状选择体积计算公式的方法;该方法存在的问题是选择计算体积公式的数理依据不足,从而会影响到其对估算资... 在现行固体矿产资源量估算规程(DZ/T 0338.2-2020)第2部分几何法中,其对平行断面块段矿体体积参数的计算采用的是传统的模拟断面形状选择体积计算公式的方法;该方法存在的问题是选择计算体积公式的数理依据不足,从而会影响到其对估算资源量成果的客观性。在文中的实例计算中,采用传统方法的计算结果其相对误差达到了7.22%。本研究探讨提出了对平行断面法客观计算矿体体积参数的新方法,可为其估算资源量提供客观的体积参数值成果。 展开更多
关键词 资源量估算 平行断面法 矿体体积 矿截 新方法
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鄂尔多斯盆地南部店头铀矿床油气-铀成矿机理探讨
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作者 刘坤鹏 武正乾 +6 位作者 毛宁 于宏伟 李亚锋 张良 王晓鹏 刘凯鹏 屈伸 《世界核地质科学》 CAS 2024年第2期250-260,共11页
以鄂尔多斯盆地南部店头铀矿床为研究对象,总结研究区地层、构造、油气渗出和铀矿床特征,从油气渗出、氧化渗入、铀矿体与断缝体及铀-油气相互作用四个方面探讨了油气渗出作用与铀成矿关系。认为店头地区发育系列NEE向、近EW向断缝体,... 以鄂尔多斯盆地南部店头铀矿床为研究对象,总结研究区地层、构造、油气渗出和铀矿床特征,从油气渗出、氧化渗入、铀矿体与断缝体及铀-油气相互作用四个方面探讨了油气渗出作用与铀成矿关系。认为店头地区发育系列NEE向、近EW向断缝体,是深部延长组油气向上运聚的主要通道,伴有油浸、脉状石膏和黄铁矿等;油气渗出作用表现为油浸砂岩、褪色蚀变砂岩和地沥青三种样式,其中铀成矿期形成的地沥青或凝胶化有机质对铀沉淀富集起关键作用,成矿期后形成褪色蚀变砂岩或油浸砂岩只是对铀矿起到保矿作用;放射性元素对地沥青和凝胶化有机质催化热解作用,有机质活性及还原吸附能力增强;矿石中沥青铀矿或铀石围绕凝胶化有机质或黄铁矿赋存,具有多期环带状产出的特点,伴生方铅矿、闪锌矿和黄铜矿等中低温热液硫化物;渗出流体长期作用下的水-岩反应致使直罗组砂岩总体硬度大,密度较大,孔隙度和渗透率较低。认为店头地区铀成矿受渗出还原作用与渗入氧化作用动态作用成矿,形成高品位铀矿化,NEE向和近EW向断缝体是区域铀成矿关键控矿要素。旨在进一步阐明店头矿床铀成矿机理,识别并构建区域铀矿找矿标志,为选区和铀矿勘查部署提供依据。 展开更多
关键词 店头铀矿床 成矿机理 断缝体 铀成矿 油气渗出 凝胶化有机质
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Reconstruction of Ore-controlling Structures Resulting from Magmatic Intrusion into the Tongling Ore Cluster Area during the Yanshanian Epoch 被引量:13
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作者 DENG Jun WANG Qingfei +5 位作者 YANG Liqiang GAO Bangfei HUANG Dinghua LIU Yah XU Hao JIANG Shaoqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第2期287-296,共10页
The Tongling ore cluster area experienced intensive compression and associated shearing during the Indosinian-Yanshanian Epoch, which formed a trunk ore-controlling fold and fault system in the caprock. The magmatic i... The Tongling ore cluster area experienced intensive compression and associated shearing during the Indosinian-Yanshanian Epoch, which formed a trunk ore-controlling fold and fault system in the caprock. The magmatic intrusion in the Yanshanian Epoch induced a multi-stage unmixing of poly-phase fluids, resulting in mineralization characterized by multi-layer, wide-range, and multiform styles. The magmatic intrusion in the Tongling area not only supplied the essential ore-forming materials, but also reconstructed the ore-controlling structures according to a trend surface simulation of the following five strata boundaries: Silurian-Devonian, Devonian-Carboniferous, Carboniferous- Permian, Middle Permian-Upper Permian and Permian -Triassic. The result of this simulation shows that there exists a significant difference between the strata in the upper part and those in the lower. The lower trend surfaces are antiform whereas the upper trend surfaces are synform. In addition, superposing of the trend surfaces of adjacent bed boundaries (such as, Silurian-Devonian boundary superposed upon Devonian-Carboniferous boundary) shows that the lower trend surface always pierces the one above. Moreover, the position and orientation of the pierced parts of the different superposed trend surfaces are similar and show E-W-trending zonal distribution in accordance with the distribution of the regional E-W-trending magmatic-metallogenic belt. Based on comprehensive analysis of the mechanical properties of the strata, structural deformation mechanisms, and field phenomena, it seems that the special characteristics of the stratal trend surface resulted from jacking due to magmatic intrusion into the caprock previously controlled by an E-W-trending basement fault. Therefore, it is deduced that the major ore-controlling structures, which formed during regional horizontal compression, were reconstructed by the vertical jacking function of ore-forming magmas during the Yanshanian Epoch. During the ore-forming process, the local vertical jacking of magmas, coupled with the regional horizontal compression, optimized an extensive environment in the fluid- conduit network and accelerated the unmixing of poly-phase fluids following magmatic emplacement. Jacking also strengthened the vertical and lateral fluid-guiding structures, supplying more suitable physical conditions for multi-layer emplacement and wide-ranging transport of poly-phase fluids. 展开更多
关键词 magma trend surface multi-layer mineralization UNMIXING Tongling ore cluster area YANSHANIAN
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Metallogenic Epoch and Ore-forming Environment of the Lamasu Skarn-porphyritic Cu-Zn deposit,western Tianshan,Xinjiang,NW China 被引量:22
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作者 ZHANG Zuoheng WANG Zhiliang +1 位作者 WANG Longsheng ZUO Guochao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期731-740,共10页
Granitic rocks, widely developed in the Lamasu copper ore region, western Tianshan were formed at 390.5±7.7 Ma according to the SHRIMP zircon U-Pb dating of the plagioclase granite porphyry. Based on the regional... Granitic rocks, widely developed in the Lamasu copper ore region, western Tianshan were formed at 390.5±7.7 Ma according to the SHRIMP zircon U-Pb dating of the plagioclase granite porphyry. Based on the regional tectonic evolution and published chronological data of both diagenesis and mineralization, the Biezhentao- Kokirqin region was rolled into the orogen associated with the closure of Yili Ocean during early Devonian. The N-S-trending thrust faults were formed during this period and accompanied by the intrusion of granitic rocks. On this stage, the paleo-Asian Ocean Plate entered into the early collision orogenic phase and the plagioclase granite porphyry intruded (390.5±7.7 Ma) and replaced with limestone of the Mesoproterozoic Kusongmuqieke Group, Jixianian System and formed the early phase of skarn-type copper mineralization in the Lamasu region. Furthermore, the subduction-melting of Bayingou Ocean Plate during Carboniferous generated a deep-seated magmatic chamber in the Lamasu copper ore region which located in the northwestern part of the Paleozoic Biezhentao-Kokirqin island arc. The magmatic chamber segregated Cu-bearing magmas, which transported upward to the shallow earth crust along the faults or fractures and formed the Cu-hosting porphyry. According to the research on the characteristics of the ore deposit and the ore-forming environment as mentioned above, the Lamasu Cu-Zn deposit was characterized by the superposing of mineralization at different geological settings and it was skarn-porphyritic type. 展开更多
关键词 Lamasu copper ore deposit diagenesis and mineralization ages western Tianshan
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