102 resultados para ICP-AES


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The mineralogical and geochemical characteristics of Fe-oxyhydroxide samples from one dredge station (long. 103 degrees 54.48'W, lat. 12 degrees 42.30'N, water depth 2655 m) on the East Pacific Rise near lat 13 degrees N were analyzed by XRD, ICP-AES, and ICP-MS. Most Fe-oxyhydroxides are amorphous, with a few sphalerite microlites. In comparison with Fe-oxyhydroxides from other fields, the variable ranges in the chemical composition of Fe-oxyhydroxide samples are very narrow; their Fe, Si, and Mn contents were 39.90%, 8.92%, and 1.59%, respectively; they have high Cu (0.88%-1.85%) and Co (65x10(-6)-704x10(-6)) contents, and contain Co+Cu+Zn+Ni > 1.01%. The trace-element (As, Co, Ni, Cu, Zn, Ba, Sr) and major-element (Fe, Ca, Al, Mg) contents of these samples are in the range of hydrothermal sulfide from the East Pacific Rise near 13 degrees N, reflecting that this type of Fe-oxyhydroxide constitutes a secondary oxidation product of hydrothermal sulfide. The Fe-oxyhydroxide samples from one dredge station on the East Pacific Rise near 13 degrees N are lower in Sigma REE (5.44x10(-6)-17.01x10(-6)), with a distinct negative Ce anomaly (0.12-0.28). The Fe-oxyhydroxide samples have similar chondrite-normalized rare-earth-element (REE) patterns to that of seawater, and they are very different from the REE composition characteristics of hydrothermal plume particles and hydrothermal fluids, showing that the REEs of Fe-oxyhydroxide are a major constituent of seawater and that the Fe-oxyhydroxides can become a sink of REE from seawater. The quick settling of hydrothermal plume particles resulted in the lower REE content and higher Mn content of these Fe-oxyhydroxides, which are captured in part of the V and P from seawater by adsorption. The Fe-oxyhydroxides from one dredge station on the East Pacific Rise near 13 degrees N were formed by secondary oxidation in a low temperature, oxygenated environment. In comparison with the elemental (Zn, Cd, Pb, Fe, Co, Cu) average content of hydrothermal sulfide samples from the East Pacific Rise near 13 degrees N, the Zn, Cd, and Pb contents of the Fe-oxyhydroxides are lower, and their Fe, Co, and Cu contents are higher.

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本文利用ICP-AES、EPMA、X-ray衍射等测试技术以及聚类分析和因子分析等多种数理统计方法,系统地对中太平洋海区富钴结壳的元素地球化学特征、矿物组成和微观组构进行了研究,并探讨了其成因机制,获得以下主要认识: 1中太平洋海区富钴结壳类型多样,均为水成成因,其矿物相主要由锰矿物相、铁矿物相和非金属矿物相组成;富钴结壳壳层发育多种原生和次生构造类型。 2磷酸盐化作用不仅强烈改变富钴结壳元素初始含量,而且造成富钴结壳某些元素间的相关性发生改变,这些敏感型元素对可用于指示富钴结壳是否发生磷酸盐化。在不同水深段内,未磷酸盐化型富钴结壳的主要元素随经向、纬向的变化趋势相似,表明其受水体化学障、表面生产力和物质来源等环境参数控制;而随水深的变化则具有区域一致性,表明水体化学具有区域成层性。 3未磷酸盐化富钴结壳稀土元素含量和轻重稀土分馏程度随水深发生规律变化,这种变化不仅与它们在海洋中的含量和行为有关,也与海洋背景颗粒的吸附有关;铈(Ce)在富钴结壳中基本上呈4价,且动力学因素控制了其富集过程,因此Ce异常不能用于指示富钴结壳形成环境的氧化程度。 4基于富钴结壳微层呈锯齿状且同一微层生长速率不同,提出了富钴结壳在各种基底表面生长以及后继发育过程受固液界面双电层控制的发育模式。在富钴结壳整个发育过程中,经历了从贫氧环境向富氧环境的转变,但微环境则呈富氧-低氧过程的交替。 关键词: 富钴结壳;中太平洋;元素地球化学;界面双电层

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利用全谱直读等离子体发射光谱法(ICP—AES)测定了3种秦艽组植物10种微量元素(Cu,Zn,Fe,Mn,Ni,Co,Sn,V,Al,Ti)的含量,并进行了比较分析。结果表明,所测定元素在3个不同物种内的含量排列顺序基本一致,显示了三者在元素富集方面的相似性。就同一种元素在3个物种内的富集水平而言,以麻花艽根部具有较高含量的元素Cu,Zn,Co,Al和Ti,管花秦艽根部则大量富集了其余5种微量元素,达乌里秦艽对元素的吸收积累能力居中,揭示了不同物种对同一元素富集能力的差异。该研究可为秦艽类植物资源的深入开发利用提供参考。

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采用ICP-AES法对生长在同一区域内的白刺与枸杞根茎中的8种微量元素的含量进行了分析测定。结果表明,两种植物根茎中8种元素含量丰富,并且差异明显,为以后的开发利用提供了基础数据。

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采用ICP-AES法对青海省内采集的麻花艽中的铜、锌、铁、锰的含量进行了测定。结果表明,麻花艽中四种元素含量丰富,各部位含量差异较大,其中基部茎部含量较高,入药部位根部次之,为以后的开发利用提供了基础数据。

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名贵藏成药七十味珍珠丸是传统藏药的典型代表,疗效显著.其中矿物类药的大量运用为现代医学科学不可理喻,给传统藏医药学的健康发展带来了困惑.以金诃七十味珍珠丸为研究材料,以Wistar大白鼠为试验对象,用等离子体发射光谱(ICP-AES)和氢化物原子吸收光谱(HAAS)等分析仪器,测定了对照组和给药组实验动物在连续18周试验期间心、肝、肾等组织器官中的矿物质元素含量水平,阐述金诃七十味珍珠丸中矿物质元素在动物主要组织器官中的长期蓄积性及其对生物机体的毒性效应.

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用ICP - AES法测定了名贵藏药七十味珍珠丸中微量和常量元素的含量, 并结合其药效进行讨论。

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Using knowledge of geology, geochemistry, coal petrology, mineralogy, by means of a variety of advanced measuring methods such as inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled atomic emission spectrometry (ICP-AES), X-ray powder diffraction (XRD), scanning electron microscopy with energy-dispersive spectrometer(SEM-EDS), sequential chemical extract and density fractions, the characteristics of trace elements and minerals in Jurassic Beipiao coal mine under inland limnetic sedimentary environment and in late Permian Jianxin and Qiaotou coal mines under paralic swamp sedimentary environment were studied. Compared with the average concentration in the world bituminous coals, the Beipiao coal was characterized by relatively high contents of Sc, Ti, Cr, Co, Ni, Zn, Se, Sr, Zr, Y, Ba, REE and Th, and lower contents of V, Rb, Cd, Sn, Pb, Bi and U; while the Jianxin coal was relatively enriched in Li, Sc, Ga, Sr, Y, Nb, Sb, Th and U, with low concentration of Be, Co, Ni, Cu, Ge, Zr, Mo, Cd, Cs, Ba, Pb and Bi; and the Qiaotou coal was enriched in Li, Sc, Sr, Nb, Ta, Zr, REE, Hf, Th and U, with low concentration of Be, V, Co, Ni, Cu, Ge, Mo, Cd, Cs, Ba, Tl, Pb and Bi. The concentrations of Ca, Mg and K in Beipiao coal are higher than those in Jianxin coal and Qiaotou coal, while Fe, S and Ti in Beipiao coal are lower than those in Jianxin coal and Qiaotou coal. The proximate analysis of coal samples was carried out, which indicated that Beipiao coal was medium- to high- ash (5.92-60.68%) with low sulphur coal, and Jianxin coal and Qiaotou coal was medium to high ash (8.85-46.33%) with high sulphur. The reflectivity was measured, which explained that Beipiao coal belonged to high volatile bituminous coal, Jianxin coal was low volatile bituminous coal and Qiaotou coal was low volatile anthracite. Quantitative maceral analyses were studied. The characteristics of rare earth elements (REE) were investigated, which showed that the total contents of REE were higher than that of the world's average content. With the increase of coal's metamorphic grade, the total contents of REE decreased from 98.5 X 10"6 of Beipiao coal to 94.2 X 10"6 of Jianxin coal, and to 75.9 X 10"6 of Qiaotou coal, and 5Eu reduced which indicated that the element Eu depleted. The characteristics of REE was controlled by the metamorphic grade of coal. And REE were mainly absorbed in clay minerals in Beipiao coal samples, while in Jianxin and Qiaotou coal mines, REE were primarily related to clay mineral and pyrite. The variation of trace elements in vertical direction of coal seams was studied, and the results showed that different trace elements differed greatly. The correlation between trace elements and ash were determined. Four major trace elements (aluminium-silicates, sulphide, carbonate and phosphate) accounted for the occurrence and distribution of most elements studied were determined. Coal samples were separated by density fraction, which showed that Cr, Cu, Mo and Pb were closely related to inorganic matters mainly distributed in P >2.6 and dropped remarkably in the density fractions P <2.3 . The occurrences of Co, Cr, Ni, As, Se, Mo, U were studied directly and quantitatively using sequential chemical extract with six steps, which showed that Co. Ni, Mo and U were mainly in the form of mineral, and As, Se chiefly in the form of organic state, while Cr mostly in the form of organic state and mineral. Major mineral phases presented in the Beipiao coal were Kaolinite, illite, quartz, calcite, and small amount of siderite, barite. While major mineral phases in Jianxin and Qiaotou coal were pyrite, kaolinite, and small amount of marcasite, rutile, sphalerite. This is the first time that the chromite in the coal was discovered in China, which indicates that Cr occurrence appeared in the form of chromite. The ratio of Sr/Ba, Sr/Ca and V/Ni in Beipiao coal mine under inland limnetic is smaller than that of in Jianxin and Qiaotou coal mines under paralic swamp. The ratio of K/Na and Th/U of Beipiao coal mine is higher than that of Jianxin and Qiaotou coal mine, which proved that Beipiao coal was not affected by sea water and Jianxin and Qiaotou coal were affected by sea water. Trace elements such as Cr, Ni, Mo in minerals were analyzed by SEM-EDS. The factors controlling the enrichment of trace elements can be divided into syngenetic stage factors and epigenetic stage factors.

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Distributions of elements especially hazard trace elements in coals and their wastes from a coal fired power plant have been studied in detail using knowledge of Geology, Mineralogy, Geochemistry and Environmental chemistry. The key work is on the small particle sizes of fly ashes which escaped from electric precipitator and discharged into atmosphere. By means of X-ray powder diffraction (XRD) and scanning electron microscopy with energy-dispersive spectrometer (SEM-EDS), the characteristics of minerals and morphologies were studied. Different types of fly ash were formed in different stages and processes. More than 50% of small fly ashes belonged to inhalable particles (PM10). The very fine fly ashes preferred to attach on surface of bigger fly ash or conglutinate with each other and this decreased the environmental impact of tiny fly ashes. The trace elements in coal, fly ashes, slags and small particle sizes of fly ashes had been analysed by means of Neutron Activation Analysis (INAA), inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectrometry (ICP-AES). As particle sizes decreasing, distributions of most elements increased, but in contrary to most studies, this increasing trend was not very obviously because of the tendency of attachment of tiny fly ashes. The occurrence of 30 elements including hazard trace elements of Cd, Cr, Ni, Co, Pb, Zn, As, Se, Cu, V was studied by means of sequential chemical extract. The annual discharge of hazard trace elements of slag, fly ash, small fly ash (PM10), tiny fly ash (PM2.5) and air was calculated by mass balance. S, V, Cu, Pb, Se, Mo, Cd from power plant had potential impacts on environment. Hazard trace elements from the power plant had little effect on soil and aerosol comparing to those from other industrial sources and the effects were mostly on downwind direction. Both the high performance electric precipitator and high chimney made the hazard trace elements from power plant being transported far away but little environmental impacts.

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根据以往研究 ,选取了 2个砷含量差异较大的样品 ,利用连续浸取实验 ,结合仪器中子活化分析 (INAA)、等离子原子吸收光谱 (ICP -AES)、等离子质谱 (ICP -MS)测定及X射线吸收精细结构 (XAFS)分析 ,经低温灰化 (LTA)、扫描电子显微镜 (SEM -EDX)对黔西南高砷煤中砷的赋存状态进行了研究 ,发现 5 0 %以上的砷不能被NH4 Ac、HCl、HF和HNO3 等无机试剂提取出来 ,结合以往的研究认为砷主要以高价有机砷的形式存在

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长久以来,对于陨石金属相的全岩研究主要使用中子活化分析方法(INAA),该方法具有灵敏度高、无损样品及制样简单等优点,但它无法测定所有铂族元素(PGEs)。随着分析技术的发展,电感耦合等离子质谱(ICP-MS)越来越广泛地应用于地质学领域,但在地外物质的应用中研究较少。 本论文在分析方法上,首先在国内开展了球粒陨石金属相和铁陨石的主、微量元素的ICP-AES和ICP-MS实验分析方法研究,对四块球粒陨石的金属相以及四块铁陨石进行了分析,初步讨论了星云凝聚和小行星热变质中亲铁元素的变化特征,进一步揭示了星云的凝聚过程、以及铁陨石的结晶过程。对新发现的乌拉斯台铁陨石所做的研究表明,该陨石和新疆陨石可能为成对陨石。并将研究延伸到地外撞击事件的研究中,通过对浙江煤山P/T界线层的样品进行分析,对当时的生物大灭绝事件给出了合理解释。 乌拉斯台铁陨石是在我国新疆新发现的一块铁陨石,其发现地点距离新疆铁陨石(Armanty)约130公里。我们应用ICP-MS分析了乌拉斯台铁陨石(IIIE),以及新疆铁陨石(IIIE)、南丹铁陨石(IIICD)和Mundrabilla铁陨石(IIICD)的全岩组成,结果显示和参考文献有很好的一致性,证明了该分析方法的可行性。我们对乌拉斯台铁陨石进行了系统的岩石学、矿物学、以及微量元素分析,该陨石的岩石结构属于粗粒八面体,铁纹石带宽为1.2  0.2 mm。合纹石以各种微观结构大量存在于该陨石中。陨磷镍铁矿以富镍(30.5-55.5%)的形式出现在合纹石中,或者与陨硫铁,陨硫铬铁矿等共生。并通过计算获知该陨石的冷却速率约为20℃/Myr。其岩石矿物学特征和全岩组成和新疆铁陨石相似,二者都落在IIIE化学群的范围,因此,我们将乌拉斯台铁陨石划分为IIIE化学群,并初步认为和新疆铁陨石是成对陨石。同时,对吉林球粒陨石(H5)、安龙球粒陨石(H5)、以及南极陨石GRV 9919(L3)和GRV 021603(H3)四块球粒陨石金属相进行的研究显示,球粒陨石金属相的亲铁元素配分模式主要与元素的挥发性相关,具有难熔元素基本上平坦分布,而中等和强挥发性元素随其挥性的增高而趋于贫化的特征。 铂族元素的研究不仅在讨论星云凝聚过程中亲铁元素的分异、金属-硅酸盐分异与核-幔的形成,以及金属熔体的结晶分异方面有着重要的意义,对于讨论地外物质的示踪也有着重要的作用。铂族元素在地壳中高度亏损,但在大部分地外物质中富集,因此通常将Ir的异常已否作为是否有地外物质加入的重要依据之一。距今2.51亿年前的二叠纪-三叠纪(P/T界线)时期,发生了地质历史上最大规模的生物灭绝事件,然而对于该事件的诱因却一直存有争议,主要存在两种观点:“地外撞击”和“火山喷发”。我们使用锍镍火试金和同位素稀释法,结合Te共沉淀, 应用ICP-MS分析技术,对我国煤山二叠纪-三叠纪界线层的样品进行了Ir、Ru、Rh、Pt和Pd的测定。火试金方法结果显示Ir的含量为0.053 ng/g,而同位素稀释法对P/T界线事件层样品的分析结果显示,Ir的含量在0.005-0.028 ng/g,两种分析方法的结果均显示没有Ir的正异常。将PGE使用碳质球粒陨石标准化后,整个配分模式呈现出高度分异,Ir/Pd的比值为0.02-0.03CI,明显不同于各类陨石。相反,该界线层样品的PGE配分模式和西伯利亚玄武岩(甚至也可能和峨眉山玄武岩)相似,证明了该界线层样品中的PGE可能来源于玄武岩。P/T界线层样品中PGE的含量从富含黄铁矿的壳层24f向26层呈上升趋势,且在26层为最大值,然后在28层回落,这种趋势可能暗示了玄武岩最大规模的喷发可能出现在26层。该结果有力地证明了P/T界线时期的生物灭绝事件与火山喷发的相关性,给一直存有争议的二叠纪-三叠纪生物灭绝事件提供了新的证据。

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A series of PtRu nanocomposites supported on H2O2-oxidized multi-walled carbon nanotubes (MWCNTs) were synthesized via two chemical reduction methods - one used aqueous formaldehyde (HCHO method) and the other used ethylene glycol (EG method) as the reducing agents. The effects of the solvents (water and ethylene glycol) and the surface composition of the MWCNTs on the deposition and the dispersion of the metal particles were investigated using N-2 adsorption. TEM. ICP-AES. FTIR and TPD. The wetting heats of the MWCNTs in corresponding solvents were also measured. The characterizations suggest that combination of the surface chemistry of the MWCNTs with the solvents decides the deposition and the dispersion of the metal nanoparticles. These nanocomposites were evaluated as proton exchange membrane fuel cell anode catalyts for oxidation of 50 ppm CO contaminated hydrogen and compared with a commercial PtRu/C catalyst. The data reveal superior performances for the nanocomposites prepared by the EG method to those by the HCHO method and even to that for tile Commercial analogue. Structure performance relationship of the nanocomposites was also studied. (C) 2005 Elsevier Ltd. All rights reserved.