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Association between body mass index and lumbar spine volumetric bone mineral density in diabetic and non-diabetic patients
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作者 Fang Lv Xiao-Ling Cai +4 位作者 Xiu-Ying Zhang Xiang-Hai Zhou Xue-Yao Han Yu-Feng Li Li-Nong Ji 《World Journal of Diabetes》 2025年第2期103-113,共11页
BACKGROUND The association between body mass index(BMI)and bone mineral density(BMD)has shown inconsistent results,varying by sex and skeletal site.Despite normal or elevated bone mass,individuals with type 2 diabetes... BACKGROUND The association between body mass index(BMI)and bone mineral density(BMD)has shown inconsistent results,varying by sex and skeletal site.Despite normal or elevated bone mass,individuals with type 2 diabetes have an increased risk of hip and vertebral fractures.AIM To assess lumbar spine trabecular volumetric BMD(vBMD)across different BMI categories in individuals with and without diabetes.METHODS This cross-sectional study included 966 men over 50 years old and 1001 postmenopausal women from the Pinggu Metabolic Disease Study.The vBMD of lumbar vertebrae 2 through 4 was measured using quantitative computed tomography.Total adipose tissue,subcutaneous adipose tissue(SAT),visceral adipose tissue(VAT),and lumbar skeletal muscle area were also quantified.RESULTS In men with obesity(P=0.038)and overweight(P=0.032),vBMD was significantly higher in the diabetes group compared to non-diabetic men.After adjusting for age and sex,no significant saturation effect between BMI and BMD was found in participants with diabetes or in women without diabetes.However,a BMI threshold of 22.33 kg/m²indicated a saturation point for vBMD in nondiabetic men.Independent predictors of vBMD in men included age(r=-0.387,P<0.001),BMI(r=0.130,P=0.004),and VAT(r=-0.145,P=0.001).For women,significant predictors were age(r=-0.594,P<0.001),BMI(r=0.157,P=0.004),VAT(r=-0.112,P=0.001),and SAT(r=-0.068,P=0.035).CONCLUSION The relationship between BMI and trabecular vBMD differs in individuals with and without diabetes.Overweight and obese men with diabetes exhibit higher vBMD. 展开更多
关键词 Obesity and overweight body mass index DIABETES Lumbar spine volumetric bone mineral density Quantitative computed tomography
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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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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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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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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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Imaging the Architecture of Mineral Systems and the Pathways of Ore-forming Fluids across Mongolia with Magnetotellurics
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作者 Matthew J.COMEAU Rafael RIGAUD +4 位作者 Erdenechimeg BATMAGNAI Shoovdor TSERENDUG Sodnomsambuu DEMBEREL Michael BECKEN Alexey KUVSHINOV 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期11-13,共3页
In the framework of a mineral system approach,a combination of components is required to develop a mineral system.This includes the whole-lithosphere architecture,which controls the transport of ore-forming fluids,and... In the framework of a mineral system approach,a combination of components is required to develop a mineral system.This includes the whole-lithosphere architecture,which controls the transport of ore-forming fluids,and favorable tectonic and geodynamic processes,occurring at various spatial and temporal scales,that influence the genesis and evolution of ore-forming fluids(Huston et al.,2016;Groves et al.,2018;Davies et al.,2020).Knowledge of the deep structural framework can advance the understanding of the development of a mineral system and the emplacement of mineral deposits.Deep geophysical exploration carried out with this aim is increasingly important for targeting new ore deposits in unexplored and underexplored regions(Dentith et al.,2018;Dentith,2019). 展开更多
关键词 MAGNETOTELLURICS electrical resistivity mineral exploration mineral emplacement ore fluids fluid transport
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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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Dephosphorization of high-phosphorus iron ore by direct reduction of hydrogen-rich gases and melting separation
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作者 ZHAO Lian-da WU De-yin +6 位作者 YOU Xiao-min DENG Xing-jian ZUO Hai-bin SHE Xue-feng XUE Qing-guo WANG Guang WANG Jing-song 《Journal of Central South University》 CSCD 2024年第11期4120-4136,共17页
This study developed a direct reduction route to smelt refractory high-phosphorus iron ores by using hydrogen rich gas.The effects of temperature,gas composition,and gangue on the reduction behavior of iron ore pellet... This study developed a direct reduction route to smelt refractory high-phosphorus iron ores by using hydrogen rich gas.The effects of temperature,gas composition,and gangue on the reduction behavior of iron ore pellets were investigated.Additionally,the migration behavior of phosphorus throughout the reduction-smelting process was examined.The apparent activation energy of the reduction process increased from 64.2 to 194.2 kJ/mol.Increasing the basicity from 0.5 to 0.9 increased the metallization rate from 85.9%to 89.2%.During the reduction process,phosphorus remained in the gangue phase.Carbon deposition and phosphorus removal behaviors of the pellets were investigated and correlated with the gas composition,temperature,pressure,metallization rate,and basicity.Increasing the FeO and CaO contents led to an increase in the liquidus temperature.A high metallization rate of the pellets reduced the phosphorus removal rate but increased the carbon content of the final iron product.Increasing basicity restricted the migration of phosphorus and improved the rate of phosphorus removal.The optimum dephosphorization parameters were separation temperature of 1823 K,basicity of 2.0,and metallization rate of 82.3%.This study presents a high-efficiency and low carbon method for smelting high-phosphorus iron ores. 展开更多
关键词 high-phosphorus iron ore hydrogen-rich gas reduction phosphorus transport mineral evolution melting separation
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中低温岩浆热液型金矿床找矿预测地质模型
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作者 薛建玲 庞振山 +5 位作者 程志中 陈辉 张晓飞 贾儒雅 俞炳 牟妮妮 《岩石学报》 SCIE EI CAS 北大核心 2025年第1期4-30,共27页
我国金矿资源对外依存度长期居高不下,立足国内,寻找并探明一批大型金矿床是一项迫在眉睫的重大任务。中低温岩浆热液型金矿床是我国金的最主要来源,如何寻找其隐伏矿和深部矿成为当前矿产勘查研究的热点。本文以勘查区找矿预测理论为指... 我国金矿资源对外依存度长期居高不下,立足国内,寻找并探明一批大型金矿床是一项迫在眉睫的重大任务。中低温岩浆热液型金矿床是我国金的最主要来源,如何寻找其隐伏矿和深部矿成为当前矿产勘查研究的热点。本文以勘查区找矿预测理论为指导,以中低温岩浆热液型金矿床为研究对象,总结了中低温岩浆热液型金矿床地质特征,构建了以成矿地质体、成矿构造和成矿结构面特征和成矿作用特征标志为核心内容的找矿预测地质模型,为该类型金矿床找矿预测提供了新的思路,指导隐伏矿和深部矿金资源勘查取得突破。中低温岩浆热液型金矿床分为中温岩浆热液型金矿床和低温岩浆热液型金矿床两个亚类,广泛发育于陆块区和造山带中,赋矿围岩多种多样,成矿时代广泛,主要集中在中生代。本文厘定了中低温岩浆热液型金矿床成矿地质体为中酸性侵入体,与矿床(体)呈现出空间上相依(1~5km)、时间上相近(10Myr)、成因上相关的内在成生联系和时空配置关系。成矿构造属褶皱、断裂、岩浆侵入复合构造系统;成矿结构面主要有断裂、硅钙面、岩溶构造及岩体侵入接触带、爆破角砾岩体及水压裂隙等;矿化样式受成矿结构面控制,大致可分为四个类型:层状、脉状、块状及其组合而成的复合型。中温岩浆热液型金矿床成矿作用早阶段温度可达450℃左右,形成强度不等的钾长石化、钠长石化或铁白云石化;主成矿阶段成矿温度250℃左右,蚀变主要为硅化、绢云母化、伊利石化,Au和Ag共伴生,同时伴生少量Pb、Zn、Cu等,主要金属矿物为黄铁矿,次为黄铜矿、磁黄铁矿、方铅矿和闪锌矿;而低温岩浆热液型金矿床成矿作用主阶段温度低于250℃,Au和As、Sb共伴生,Ag含量低,常见毒砂和辉锑矿等矿物,成矿作用早阶段蚀变则主要为硅化,有的为次生石英岩化。金的沉淀富集机制包括流体的沸腾、混合和交代等机制。成矿作用中心位于岩体外接触带2~3km和接触带之内,由浅部到深部形成“上脉下层”的二元结构模式,脉状矿体具有侧伏延深规律,在此基础上构建了找矿预测地质模型。在该模型指导下,我们重新厘定了我国重要成矿区带金矿床类型,在深部发现新的矿体样式,拓宽了深部找矿空间,提升了我国重要成矿区带成矿规律的认识水平,带动了我国重要成矿区带金矿找矿新突破。 展开更多
关键词 中温岩浆热液型金矿床 低温岩浆热液型金矿床 成矿地质体 成矿构造与成矿结构面 成矿作用特征标志 找矿预测模型
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洪海沟矿床北西矿带头屯河组下段砂体非均质性特征与铀成矿关系
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作者 罗星刚 郭锐 《铀矿地质》 2025年第1期62-73,共12页
近年来由于在伊犁盆地南缘西端洪海沟矿床找矿勘查工作中取得了显著成效,特别是对新层位头屯河组的投入不断增加,落实了特大型规模铀矿床,因此深入研究矿床北西矿带成矿特征对于指导矿床外围勘查工作尤为重要。本次研究分别从砂体外部... 近年来由于在伊犁盆地南缘西端洪海沟矿床找矿勘查工作中取得了显著成效,特别是对新层位头屯河组的投入不断增加,落实了特大型规模铀矿床,因此深入研究矿床北西矿带成矿特征对于指导矿床外围勘查工作尤为重要。本次研究分别从砂体外部形态和内部结构两方面入手,对洪海沟矿床北西矿带头屯河组下段砂体厚度、砂地比、非渗透性岩石层数及累计厚度进行了数据统计,对矿床北西矿带头屯河组下段砂体非均质性进行了定量化表征,判断其与铀成矿关系,发现区内含矿砂体受河道沉积相带变化因素较为密切,砂体厚度在20~30 m,砂地比在40%~60%时,非渗透性岩石隔夹层层数为0~2层、累计厚度为0~3 m时,铀成矿几率最高,铀矿化多出现在砂岩粒度为粗粒的部位。本次研究成果对类似铀矿体的寻找以及矿体边界的确定有一定的指导作用。 展开更多
关键词 砂体非均质性 头屯河组 铀成矿 洪海沟矿床
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老年骨质疏松风险预测新标杆—TyG-BMI的诊断潜力
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作者 郭丰硕 李美艺 +3 位作者 张子腾 王德泽 柳万国 顾锐 《中国实验诊断学》 2025年第1期51-55,共5页
目的探索胰岛素抵抗的替代标志物TyG-BMI指数对老年人骨质疏松的诊断价值。方法回顾性分析2023年1月至10月吉林大学中日联谊医院收治的100例骨质疏松症患者及100例非骨质疏松症患者的临床资料。统计2组患者的基线资料及TyG-BMI指数水平... 目的探索胰岛素抵抗的替代标志物TyG-BMI指数对老年人骨质疏松的诊断价值。方法回顾性分析2023年1月至10月吉林大学中日联谊医院收治的100例骨质疏松症患者及100例非骨质疏松症患者的临床资料。统计2组患者的基线资料及TyG-BMI指数水平、腰椎骨密度,分析TyG-BMI与BMD之间的关联。结果非骨质疏松症组空腹血糖、血清尿酸、肌酐、TyG-BMI均高于骨质疏松症组(P<0.05),而骨质疏松症组甘油三酯高于非骨质疏松症组(P<0.05)。多因素Logistic回归分析表明,TyG-BMI指数与BMD呈显著正相关,且这种关联在调整混杂因素后依然显著(P<0.05)。结论TyG-BMI指数可作为预测老年人骨质疏松风险的有效指标,具有早期筛查的临床应用潜力。TyG-BMI的简便性和经济性使其适合推广应用于老年人群的基础医疗保健中,有助于提高骨质疏松的早期诊断率。 展开更多
关键词 骨质疏松症 骨密度 胰岛素抵抗 甘油三脂葡萄糖-身体质量指数 老年人 诊断
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Nickel extraction from nickel laterites: Processes, resources, environment and cost
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作者 Zhen-fang Zhang Wei-bo Zhang +1 位作者 Zhen-guo Zhang Xiu-fa Chen 《China Geology》 2025年第1期187-213,共27页
With the development of the new energy industry and the depletion of nickel sulfide ore resources,laterite nickel ore has become the main source of primary nickel,and nickel for power batteries has become a new growth... With the development of the new energy industry and the depletion of nickel sulfide ore resources,laterite nickel ore has become the main source of primary nickel,and nickel for power batteries has become a new growth point in consumption.This paper systematically summarizes the processes,parameters,products,recovery rates,environmental indicators,costs,advantages,disadvantages and the latest research progress of mainstream nickel extraction processes from laterite nickel ore.It also provides a comparative analysis of the environmental impact and economic efficiency of different nickel extraction processes.It is found that the current nickel extraction processes from laterite nickel ore globally for commercial production mainly include the RKEF process for producing ferronickel and the HPAL process for producing intermediate products.The former accounts for about 80%of laterite nickel ore production.Compared to each other,the investment cost per ton of nickel metal production capacity for the RKEF is about 43000$,with an operational cost of about 16000$per ton of nickel metal and a total nickel recovery rate of 77%–90%.Its products are mainly used in stainless steels.For the HPAL process,the investment cost per ton of nickel metal production capacity is about 56000$,with an operational cost of about 15000$per ton of nickel metal and a total nickel recovery rate of 83%–90%.Its products are mainly used in power batteries.The significant differences between the two lies in energy consumption and carbon emissions,with the RKEF being 2.18 and 2.37 times that of the HPAL,respectively.Although the use of clean energy can greatly reduce the operational cost and environmental impact of RKEF,if RKEF is converted to producing high Ni matte,its economic and environmental performance still cannot match that of the HPAL and oxygen-enriched side-blown processes.Therefore,it can be inferred that with the increasing demand for nickel in power batteries,HPAL and oxygen-enriched side blowing processes will play a greater role in laterite nickel extraction. 展开更多
关键词 Laterite nickel ore LIMONITE SAPROLITE Nickel extraction PYROMETALLURGY Power batteries Hydrometallurgy COST Environmental impact Life cycle assessment Comprehensive utilization Mineral exploration engineering
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全身振动训练改善绝经后女性骨密度效果的Meta分析
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作者 乔正基 柴牛兵 +2 位作者 郑璐瑶 高云娜 汪洋 《中国组织工程研究》 北大核心 2025年第24期5195-5202,共8页
目的:利用Meta分析评价全身振动训练对绝经后女性骨密度的影响。方法:以全身振动训练、绝经后女性、骨质疏松和骨密度等为主题词,检索中国知网、万方数据库、PubMed、Web of Science等数据库中关于全身振动训练提高绝经后女性骨密度的研... 目的:利用Meta分析评价全身振动训练对绝经后女性骨密度的影响。方法:以全身振动训练、绝经后女性、骨质疏松和骨密度等为主题词,检索中国知网、万方数据库、PubMed、Web of Science等数据库中关于全身振动训练提高绝经后女性骨密度的研究,检索时限为各数据库建库至2024-04-03,纳入指标包括:腰椎(L_1-L_4、L_2-L_4)、股骨颈、大转子、Ward三角和全身的骨密度,使用Revman 5.3和R 4.3.3进行数据分析。结果:(1)纳入文献共计28篇,均为随机对照研究;(2)振动强度:振动频率≥20 Hz且振幅≥2 mm能显著提升股骨颈、大转子、Ward区域、L_1-L_4和L_2-L_4腰椎骨密度(P<0.01,I~2<50%);(3)训练周期与频率:每周进行两三次训练,训练次数达到48-96次,各部位骨密度均显著提高(P<0.05,I~2<50%);(4)动作模式:动态训练能显著提高股骨颈(P=0.03,I~2=0%)、大转子(P<0.001,I~2=0%)和Ward区域(P<0.001,I~2=0%)骨密度,静蹲能显著提高L_1-L_4腰椎骨密度(P<0.001,I~2=0%),静态多种蹲姿能有效提升L_2-L_4腰椎(P<0.01,I~2=0%)和股骨颈(P=0.04,I~2=34%)骨密度。结论:全身振动训练在改善绝经后女性骨密度方面具有一定潜力,建议采用的振动频率和幅度不低于20 Hz和2 mm,训练次数不低于48次,提升腰椎骨密度宜采用静态训练,提升髋部骨密度宜采用动态训练。 展开更多
关键词 绝经后妇女 骨密度 全身振动训练 振动频率:振动幅度 训练周期 运动模式 META分析
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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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Methods of predicting vertebral body fractures of the lumbar spine 被引量:6
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作者 Gurudattsingh B Sisodia 《World Journal of Orthopedics》 2013年第4期241-247,共7页
Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone minera... Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone mineral density(BMD), which may be applied in order to predict VB failure load and fracture risk. The most representative models are those that take account of normal spinal kinetics and assess the contribution of the cortical shell to vertebral strength. Overall, predictive models for VB fracture risk should encompass a range of important parameters including BMD, geometric measures and patient-specific factors. As interventions like vertebroplasty increase in popularity for VB fracture treatment and prevention, such models are likely to play a significant role in the clinical decision-making process. More biomechanical research is required, however, to reduce the risks of post-operative adjacent VB fractures. 展开更多
关键词 LUMBAR SPINE VERTEBRAL body Fracture Prediction Model Bone MINERAL density OSTEOPOROSIS
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Mineral processing plant location using the analytic hierarchy process——a case study:the Sangan iron ore mine(phase 1) 被引量:18
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作者 SAFARI Mohsen ATAEI Mohammad +1 位作者 KHALOKAKAIE Reza KARAMOZIAN Mohammad 《Mining Science and Technology》 EI CAS 2010年第5期691-695,共5页
Locating the mineral processing plant near a mine is the most important parameter that affects the whole process.Many factors,and their preferences,should be considered in this stage.The factors include economical,geo... Locating the mineral processing plant near a mine is the most important parameter that affects the whole process.Many factors,and their preferences,should be considered in this stage.The factors include economical,geological,technical,environmental and tectonic parameters.A multi-criteria decision making method is necessary to rank the alternatives.In this paper we describe how plant location is selected by using the Analytic Hierarchy Process(AHP).This method,with eight criteria,was used to select a location for the mineral processing plant at the Sangan iron ore mine(phase 1).Three alternatives for the processing plant were evaluated.The main criteria were distance from the mine,access to heavy machinery transport,the amount of excavation required for grading,bed mixture capacity,belt conveyor length,distance from the tailing dam,distance from the waste dumps and surface water diversion requirements.Finally,the alternatives were ranked and the best location was proposed. 展开更多
关键词 mineral processing multi-criteria decision making Sangan iron ore mine AHP
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Effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores 被引量:7
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作者 Gai-rong WANG Yuan-yuan LIU +3 位作者 Lin-lin TONG Zhe-nan JIN Guo-bao CHEN Hong-ying YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第10期2192-2201,共10页
The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The resul... The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The results indicated that at ambient temperature, the easily leached copper oxide minerals were completely dissolved, while the bonded copper minerals were insoluble. At lukewarm temperature of 40℃, it was mainly the dissolution of copper in isomorphism state. With increasing temperature to 60℃, the copper leaching rate in the adsorbed state was significantly accelerated. In addition, when the temperature increased to 80℃, the isomorphic copper was completely leached, leaving 11.2% adsorbed copper un-leached. However, the copper in feldspar-quartz-copper-iron colloid state was not dissolved throughout the leaching process. Overall, the leaching rates of copper in different copper minerals decreased in the order: malachite, pseudo-malachite > chrysocolla > copper-bearing chlorite > copper-bearing muscovite > copper-bearing biotite > copper-bearing limonite > feldspar-quartz-copper-iron colloid. 展开更多
关键词 complex copper oxide ores occurrence state TEMPERATURE leaching behavior copper minerals
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