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1.
岫岩玉是我国的主要玉种之一,属于蛇纹石玉。在X射线衍射、红外光谱、可见光吸收谱,及电子显微镜等项研究确切查明主体矿物为叶蛇纹石的基础上,选两个优质玉样进行~(57)Fe穆斯堡尔谱学研究。岫岩玉的穆斯堡尔谱由两组四级双峰构成,第一组双峰(δ=1.12,△=2.73与2.72mm/s)系由镁氧八面体中的Fe~(2+)形成,另组双峰(δ=0.35与0.36,△=0.63与0.55mm/s)反映的是镁氧八面体中的Fe~(3+),Fe~(3+)/Fe~(2+)分别为0.90与0.78。铁是参与叶蛇纹石晶格的组分;Fe~(3+)与Fe~(2+)均处镁氧八面体中;Fe~(3+)/Fe~(2+)近于与小于1是制约它呈绿色的主要因素。  相似文献   

2.
本文收集了我国南方4个产地的黝锡矿样品,使用电子探针、X射线衍射、~(119)Sn、~(57)Fe穆斯堡尔谱等测试方法测试。X射线衍射结果,黝锡矿的晶胞参数为:a=5.4531(5)?,c=10.7470(7)?,四方晶系,空间群I42m。4个不同产地的黝锡矿的Sn、Fe穆斯堡尔谱测量表明:锡的I·S值为1.34—1.49mm/s,Q·S值为0.36—0.50mm/s,为四面体的Sn~(4+);铁的I·S值为0.588—0.596mm/s,Q·S值为2.900—2.911mm/s,为四面体的Fe~(2+)。Sn、Fe离子仅占据一种结晶学位置。这些黝锡矿富Zn,Zn以类质同象置换Fe。  相似文献   

3.
我院FH—1918微计算机穆斯堡尔谱仪已安装调试完毕,现可对内对外接收样品,测试收费合理。 穆斯堡尔谱方法国内外发展很快,应用的范围较广。我们主要测定岩矿石,矿物(最好为单矿物)中铁的氧化状态以及Fe~(2 )或Fe~(3 )与总铁的比值。欢迎各单位送样测试。 样品要求:将岩矿石、矿物研磨成小于100目的粉末,每个样品自然铁要求10毫克。  相似文献   

4.
莱河矿中阳离子的分布   总被引:1,自引:0,他引:1  
在100—688K之间测量了河北莱河矿的穆斯堡尔谱。高温穆斯堡尔谱表明,莱河矿只显示一个Fe~(2+)双峰。没有测出铁榄橄石的存在。如果将莱河矿冷却到室温以下,则在240K首先出现磁分裂的谱线。从莱河矿的Fe~(2+)和Fe~(3+)双峰的面积比和化学成分能估算Fe~(2+)和Fe~(3+)的占位以及空位在M_1和M_2上的分布:对M_1来说为0.65Fe~(2+)+0.35□;对M_2来说为0.90Fe~(3+)+0.1□。Fe~(2+)和Fe~(3+)的同质异能位移随温度的变化率分别为-9.8×10~(-4)mm/s·K和-5.7×10~(-4)mm/s·K,计算了四极分裂与温度的相关性  相似文献   

5.
本文对中国广西大厂锡石-硫化物多金属矿田中辉锑锡铅矿进行了产出地质条件,共生组合及其形成条件的研究,并通过化学成分、X光粉晶衍射、晶胞参数测定及其晶体结构模式,~(119)Sn和”Fe穆斯堡尔谱研究,初步确定大厂辉锑锡铅矿属富铅端员的“正常”辉锑锡铅矿,其中锡和铁均为Sn~(4-)和Fe~(2+)。晶体结构是由两套无公度的晶格组成,具8C型一维超结构。  相似文献   

6.
随着科学技术的发展,矿物学研究不断地深入。新的理论和技术的引用不断促进矿物学的发展。本世纪六十年代以来矿物波谱学的兴起标志着矿物学研究进入新的发展阶段。穆斯堡尔谱是一种新的矿物波谱方法,它正被引用于矿物学研究领域。用铁的穆斯堡尔效应可以确定矿物中铁的存在状态:价态,Fe~(2 )/Fe~(3 )比值,配位数,阳离子铁的  相似文献   

7.
穆斯堡尔效应(Mbssbauer effect)是一种无反冲的核γ射线的共振吸收现象.自六十年代初发现~(57)Fe的能量为14.4Kev的γ射线无反冲共振吸收后,在物理,化学等部门逐渐得到广泛的应用.由于铁在地壳中分布非常广泛,多数矿物都含有铁,所以六十年代中以后,Fe穆斯堡尔效应应用于矿物研究,十多年来发展很快,到现在,Fe穆斯堡尔效应已成为矿物研究的一种重要工具.新近矿物穆斯堡尔谱学研究有如下几个方面:1.用穆斯堡尔方法测定矿物中阳离子位置分布矿物中阳离子位置分布和有序—无序现象是矿物学研究的重要课题.穆斯堡尔方法,为研究矿物中Fe~(2+)—Mg~(2+)位置分布及有序—无序现象提供一种简便而有效的方法,并将  相似文献   

8.
舒兰粘土矿系高岭石型粘土矿,其中Fe_2O_3的含量达1.5~2.7%。经穆斯堡尔谱研究,有二对四极双峰,IS分别为0.450~0.462、0.425~0.439mm/s,QS分别为0.938~0.958、0.397~0.476mm/s。表明其中的铁基本都是高自旋的Fe~(3+),主要赋存于蒙脱石—囊脱石晶格的配位八面体中,M_1与M_2中均分布有铁,其原子比约为1:3。  相似文献   

9.
单斜星叶石矿物的穆斯堡尔光谱学研究   总被引:1,自引:0,他引:1  
本文对产于俄罗斯希宾地区的单斜星叶石进行了不同的温度条件下的穆斯堡尔光谱效应研究,通过在温度分别在298 K,180 K和80 K条件下的分析,发现单斜星叶石由2个Fe~(2 )和1个Fe~(3 )四极双峰组成,并进行了单斜星叶石中的畸变参数包括八面体键角(σ~2)和键长变量(Δ)的计算。但是,在两个畸变参数之间存在着明显的差异,将无法对它们的穆斯堡尔参数和四极双峰进行指派。本文对温度在同质异能位移和四极分裂中的作用进行了探讨,根据通过穆斯堡尔效应和f(Fe~(3 )(O))/f(Fe~(2 )(O))的平均值获得的三价铁对全铁的比值,改写了单斜星叶石的化学式。  相似文献   

10.
李哲  金明芝 《矿物学报》1990,10(2):186-191
本文使用穆斯堡尔效应对三个铬铁矿进行了研究,测量了铬铁矿L-1在150K和298K温度下的穆斯堡尔谱和铬铁矿L-2和L-3在298K温度下的谱。使用次近邻效应解释了铬铁矿中的多重Fe~(2+)双峰,并使用二项式分布计算了Cr~(3+)、Fe~(3+)和Al占据次近邻位置的几率。在穆斯堡尔面积和二项式分布计算的基础上做出了Fe~(2+)双峰的指派。铬铁矿L-1谱在150K下进一步分裂,表明用来解释铬铁矿谱的模型是正确的。  相似文献   

11.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

12.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

13.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

14.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

15.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.  相似文献   

16.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

17.
Bellechester, Minnesota, is a small community of approximately 155 residents located on the county line between Goodhue and Wabasha counties in southeast Minnesota's karst region. Bellechester is served by a 21-year-old wastewater treatment facility (WWTF) consisting of three waste-stabilization ponds. On 28 April 1992 six sinkholes were discovered to have drained cell 2 of the WWTF resulting in the loss of approximately 8.7×106 1 of partially treated effluent and about 600 m3 of soil into previously undetected subsurface voids of unknown dimensions. In the week following the collapse, approximately 200 water wells located within a 5-km radius of the WWTF were sampled in an after-the-fact, emergency sampling program. Twelve samples with elevated fecal coliform levels, 18 samples with nitrate-nitrogen greater than the 10 mg/1 standard, and no samples with elevated chlorides were found. However, the elevated levels could not be unambiguously attributed to the WWTF collapse. This is the third WWTF to fail by sinkhole collapse in southeast Minnesota since 1974. All three collapsed lagoons have been located in similar geomorphic and stratigraphic settings. However, at least two lagoons have collapsed in the adjacent area in northeast Iowa, and these lagoons are located at different stratigraphic positions. Twenty-two WWTFs constructed in southeast Minnesota's karst region in the last 25 years have been identified as subject to potential sinkhole collapse. An unknown but significant number of manure storage lagoons, flood control structures, etc., have also been constructed in the karst region and are at risk. Public agencies are beginning to develop plans to deal with the risk associated with existing and future waste lagoons in this environment. The critical hydrogeologic parameters that can be used to prioritize the risk of collapse at existing facilities include: (1) the lithology of the first bedrock beneath each lagoon, (2) the thickness of surficial materials between the lagoon and the bedrock surface, (3) the presence and construction of liners (seepage rate), and (4) the proximity to existing sinkholes.  相似文献   

18.
The Kuskokwim River at Bethel, Alaska, drains a major mercury-antimony metallogenic province in its upper reaches and tributaries. Bethel (population 4000) is situated on the Kuskokwim floodplain and also draws its water supply from wells located in river-deposited sediment. A boring through overbank and floodplain sediment has provided material to establish a baseline datum for sediment-hosted heavy metals. Mercury (total), arsenic, antimony, and selenium contents were determined; aluminum was also determined and used as normalizing factor. The contents of the heavy metals were relatively constant with depth and do not reflect any potential enrichment from upstream contaminant sources.  相似文献   

19.
滇东南锡、银、铅、锌多金属矿床主要分布在个旧、白牛厂、都龙3个矿区,而滇东南较大的3个花岗岩体又分别出露在3个矿区或附近.花岗岩体均形成于燕山晚期,岩石化学、矿物成分相似,富含锡、银、铅、锌、钨、铜等成矿元素.矿床主金属元素组合与岩体之间的距离由远而近出现由锡、钨、(铍、铌、钽)→锡、钨、(铁)、铜、铟→锡、铅、锌、银、铟、(锑)有规律的变化.花岗岩浆是成矿物质来源和成矿热源.岩浆侵入初期使上覆地层隆起产生背斜(凹陷部位成向斜);同时使地层产生一系列裂隙、压性断层或层间断裂;岩浆侵入晚期,这些断层再次活动,表现为张性,岩浆产生的含矿热液沿由其活动所造成的断裂迁移、充填、交代、沉淀而形成矿床.  相似文献   

20.
岩石密度和超高压岩石折返速率   总被引:1,自引:3,他引:1  
在常温常压条件下对中国大陆科学钻CCSD主孔100-3000米岩心样品进行了密度测量,建立了密度连续剖面,并界定了不同超高压岩石的密度值。通过对比高温高压物性实验资料,岩石密度随着退变程度增强而降低,榴辉岩密度变化序列为3.52g/cm3→3.49g/cm3→3.07g/cm3→2.93g/cm3。超高压长英质岩石密度变化序列为3.00g/cm→2.80g/cm3→2.65g/cm3。上述实验资料是讨论不同折返阶段岩石所受浮力的基础,为研究折返速率大小提供了基本参数。本文通过折返板块运动平衡时,上浮力与粘滞力平衡这一关系式,定量研究了大陆俯冲板块的折返速率,认为密度差产生上浮力从而引起折返,温度对板块折返速率的影响最为显著;密度差大小、折返角度、折返板块大小对折返速率也有直接的影响。定量模拟分析表明,在温度高于850℃时,板块的折返速率可以超过100mm/a;当温度降至700℃时,折返速率则低于1.5mm/a。作者认为在折返早期,温度较高,板块快速折返至60-70km榴辉岩相深度;随着传导散热,温度降低,板块以较慢的速率折返至中下地壳。折返速率的估算表明,浮力是板块折返第一阶段(从>100km深部折返至<40km的中下地壳)的主要驱动力。  相似文献   

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