On the elastic behaviour of zeolite mordenite: a synchrotron powder diffraction study

The high-pressure elastic behaviour of a synthetic zeolite mordenite, Na₆Al_6.02Si_42.02O₉₆·19H₂O [a=18.131(2), b=20.507(2), c=7.5221(5) Å, space group Cmc2₁], has been investigated by means of in situ synchrotron X-ray powder diffraction up to 5.68 GPa. No phase transition has been observed within the pressure range investigated. Axial and volume bulk moduli have been calculated using a truncated second-order Birch–Murnaghan equation-of-state (II-BM-EoS). The refined elastic parameters are: V ₀=2801(11) ų, K _T0= 41(2) GPa for the unit-cell volume; a ₀=18.138(32) Å, K _T0(a)=70(8) GPa for the a-axis; b ₀=20.517(35) Å, K _T0(b)=29(2) GPa for the b-axis and c ₀=7.531(5) Å, K _T0(c)=38(1) GPa for the c-axis [K _T0(a): K _T0(b): K _T0(c)=2.41:1.00:1.31]. Axial and volume Eulerian finite strain versus “normalized stress” plots (fe–Fe plot) show an almost linear trend and the weighted linear regression through the data points yields the following intercept values: Fe(0)=39(4) GPa for V; Fe _a (0)=65(18) GPa for a; Fe _b (0)=28(3) GPa for b; Fe _c (0)=38(2) GPa for c. The magnitudes of the principal Lagrangian unit-strain coefficients, between 0.47 GPa (the lowest HP-data point) and each measured P>0.47 GPa, were calculated. The unit-strain ellipsoid is oriented with ε₁ || b, ε₂ || c, ε₃ || a and |ε₁|> |ε₂|> |ε₃|. Between 0.47 and 5.68 GPa the relationship between the unit-strain coefficient is ε₁: ε₂: ε₃=2.16:1.81:1.00. The reasons of the elastic anisotropy are discussed.An erratum to this article can be found at     

电感耦合等离子体质谱直接测定冰芯样品中痕量铅

利用电感耦合等离子体质谱仪对冰芯样品中超痕量Pb进行了直接测定。确定了测定溶液中浓度为ng/L级Pb的最佳仪器参数，载气流速、进样速度等与灵敏度之间的关系,浓度和扫描参数对分析精度的影响。仪器对Pb的质量浓度在20～100ng/L的分析精度(RSD，n=3)＜10%,标准加入回收率在85%～115%，检测下限为0.62ng/L，并给出了采自可可西里马兰冰川M3冰芯中Pb的分析结果。     

山东招远金矿集中区矿床及围岩中硫和铅同位素的研究

山东招远金矿集中区金矿床的围岩为新太古代胶东岩群变质岩和中生代花岗岩。胶东岩群、花岗岩及金矿床的δ3 4 S值分别为 4 7‰、 7 4‰和 8 1‰ ,3个数值均为正值 ,之间差值较小 ,且依次有规律增加 ,表现出它们具有硫的同源性和演化上的连续性。铅同位素也呈现相同的变化规律 ,N(2 0 7Pb) /N(2 0 4Pb)值在胶东岩群、花岗岩及金矿床中分别为 15 381、15 5 6 2和 15 4 75 ,与区内来自地幔的玄武岩的N(2 0 7Pb) /N(2 0 4Pb)的平均值 18 2 6 9相比差异非常明显。铅同位素中的 μ值均小于 9 5 8的临界线 ,表明铅来自同一构造环境下形成的岩石。此外 ,胶东岩群、花岗岩和金矿床 3者之间的接触关系也表明它们系同一矿源岩在不同地质时期演化的结果     

达索普冰芯中Pb记录反映的大气污染及其同位素证据

利用电感耦合等离子体质谱仪（ＩＣＰ－ＭＳ）及相关的超净化技术,对希夏邦马峰达索普冰芯上部４０ｍ的样品中超痕量金属元素Ｐｂ的含量进行测试的结果显示,Ｐｂ的含量自冰芯下部至上部呈显著增长趋势。Ｐｂ同位素分析表明,＾２０６Ｐｂ＋＾２０７Ｐｂ自冰芯下部至上部增长,而＾２０８Ｐｂ则呈下降趋势。Ｐｂ同位素的这种富Ｕ铅、贫Ｔｈ铅的组成演化特征显示,这种增加主要来自人类活动而非自然源,这与研究区相邻的多数发展中国     

原子荧光光谱法测定芦荟中铅和镉

应用AFS-820型双道原子荧光测定芦荟中Pb和Cd,用HNO3-HClO4 消解样品,以KBH4 作还原剂分别测定Pb和Cd。Pb和Cd检出限分别为0. 58μg/L和0. 21μg/L,相对标准偏差(RSD,n=5)均小于10%,线性范围Pb为0~100μg/L,Cd为0~80μg/L,标准加入回收率Pb为88. 2% ~108. 6%,Cd为85. 3% ~112. 8%。方法经植物国家一级标准物质验证,结果与标准值相符。     

云南万龙山锌锡多金属矿床硫、铅同位素特征及矿质物质来源研究

万龙山矿床是云南都龙锡矿田南段的一个大型锌锡多金属矿床,本次通过矿床地质特征及其同位素方法研究得出：硫化物矿石的硫同位素测试结果显示,δ³⁴S值范围-1.1×10-3~5×10^-3,峰值集中在0~2×10^-3之间,具有明显的塔式效应,与岩浆熔体硫同位素组成范围较为吻合,与海底喷流沉积型矿床的硫同位素特征有较明显的区别;推测硫源主要为岩浆来源,与老君山期岩浆作用有关,但有明显的幔源硫的参与和一定程度地层硫的混染。铅同位素²⁰⁸Pb/²⁰⁴Pb变化范围为38.472~39.2,²⁰⁷Pb/²⁰⁴Pb变化范围为15.618~15.76,²⁰⁶Pb/²⁰⁴Pb变化范围为18.312~19.156;μ值分布范围为9.51~9.73,平均9.63,介于原地幔（μ=7.80）与地壳（μ=9.81）之间,反映出壳幔混合铅的特征,据此判断矿区岩（矿）石的铅源以上地壳为主要来源,并有部分来自上地幔或下地壳的铅。结合矿床地质特征及硫、铅同位素特征,认为成矿作用主要与燕山晚期的岩浆热液有关,矿床类型为矽卡岩型锌锡多金属矿床。     

电感耦合等离子体发射光谱法测定包头稀土矿中的稀土总量

包头矿中的稀土总量根据提取稀土的工艺流程,含量范围为0.0x%~0.x%。对于高含量稀土总量（20%~80%）的测定,国家标准采用草酸盐重量法,但该方法分离干扰元素的步骤多,流程长。应用电感耦合等离子体发射光谱法不需复杂的分离步骤即可测定稀土元素,但由于受到精密度的限制,测定高含量稀土总量的波动范围较大,不易得到准确结果。本文针对包头稀土矿组成复杂、酸溶难于分解的情况,建立了应用碱熔处理样品,电感耦合等离子体发射光谱（ICP-AES）测定稀土总量的方法。用氢氧化钠、过氧化钠溶解样品,水提取熔融物,各种元素以离子或氢氧化物形式进入溶液,过滤除去铝、硅、磷等杂质元素及大量的钠盐,减小了基体元素及共存元素的干扰;以钪为内标校正仪器波动及基体效应的影响,无需基体匹配即可测定稀土总量。对于稀土总量在30%~50%的样品,相对标准偏差小于0.7%,对于稀土总量在2%的样品,相对标准偏差小于1.2%;各稀土元素回收率为98.0%~103.3%。本方法比国家标准方法简便,与文献中应用ICP-AES测定高含量稀土总量的方法相比精密度有很大改善,可快速准确地测定包头稀土矿中2%~50%的稀土总量。     

Lead Isotopic Composition and Lead Source in the Bainiuchang Ag-polymetailic Deposit,Yunnan Province,China

The Bainiuchang deposit in Yunnan Province,China,is located geographically between the Gejiu ore field and the Dulong ore field.In addition to the>7000 t Ag reserves,the deposit also boasts of large-scale Pb,Zn and Sn reserves with a lot of dispersed elements(In,Cd,Ge,Ga,etc.).We have determined systematically the Pb isotope composition of the deposit.The Pb isotope ratios of the ores that are of sea-floor exhalative sedimentary origin in the northwest of the mining district,are ~(206)Pb/~(204)Pb=17.758-18.537,~(207)pb/~(204)pb=15.175-15.862 and ~(208)pb/~(204)pb=37.289-39.424,while those of ores that are of magmatic hydrothermal superimposition origin in the southeast of the mining district, are ~(206)Pb/~(204)Pb=17.264-18.359,~(207)Pb/~(204)Pb=14.843-15.683 and ~(208)Pb/~(204)Pb=36.481-38.838, respectively.In terms of the Pb isotope composition of feldspar in magmatic rocks or magmatic whole- rock samples from the mining district,we have determined the Pb isotope composition and acquired the Pb isotope ratios as:~(206)Pb/~(204)Pb=18.224-18.700,~(207)Tpb/~(204)Pb=15.595-15.797 and ~(208)Pb/~(204)Pb= 38.193-39.608.Then,in the light of the Pb isotope composition of metamorphic rock samples from the Proterozoic basement exposed in the Dulong ore field,we have determined the Pb isotope composition and obtained the isotope ratios as:~(206)Pb/~(204)Pb=18.434-19.119,~(207)Pb/~(204)Pb=15.644-15.693,and ~(208)Pb/~(204)Pb=38.514-38.832.And the Pb isotope ratios of Cambrian sedimentary rocks,which are exposed in the Bainiuchang mining district,are ~(206)Pb/~(204)Pb=18.307-19.206,~(207)Pb/~(204)Pb= 15.622-15.809,and ~(206)Pb/~(204)Pb=38.436-39.932.By comparing the two types of ores with respect to their Pb isotope compositions,it is indicated that lead in the Bainiuchang deposit was derived largely from the lower-crust granulite which is earlier than Neoproterozoic in age,but the Yanshanian magmatic hydrothermal fluids probably provided a part of ore-forming elements such as Sn for the ore blocks in the south of the mining district.     

厦门港表层沉积物对海水中铅的吸附动力学

模拟研究厦门港表层沉积物对海水中Ｐｂ的吸附动力学及水环境条件的影响,当海水温度由２０－３０℃、ＰＨ５－８和盐度３０－４变化时,吸附速率分别提高约５０％、、个数量和５倍。吸附速率与盐度之间呈负指数相关关系。吸附过程可用交换吸附动力学模式描述。测定吸附速率常数、表观活化能和平衡吸附量等参数研究表明,沉积物对Ｐｂ的吸附性质以华东作用为主。     

钻井废泥浆综合治理技术研究

油田钻井生产每天都要产生大量的废弃泥浆，钻井废泥浆长期累积造成地表植被的严重破坏，污染土壤和水源，危及人类的生存。在对钻井废泥浆的基本物理化学性质进行研究时发现将钻井废泥浆脱水固化处置后，加入粉煤灰等工业垃圾做骨料和添加剂，用于油田井场路建设的方法，可实现钻井废泥浆的“无毒、无害、低成本、可工业化再利用”，是一项工业污染源综合治理，保护环境的先进技术。