微波消解-电感耦合等离子体质谱(ICP-MS)法测定板栗中的矿物元素及稀土元素

为了准确测定板栗中矿物元素和稀土元素的含量水平,采用冷冻干燥方式预处理样品,选用硝酸和过氧化氢体系微波消解样品,结合电感耦合等离子体质谱技术,建立了板栗中钠(Na)、钾(K)、镁(Mg)、锰(Mn)、铁(Fe)、钒(V)、钴(Co)等19种矿物元素及镧(La)、铈(Ce)、镨(Pr)、钕(Nd)、钐(Sm)、铕(Eu)、钆(Gd)、铽(Tb)、镝(Dy)、钬(Ho)、铒(Er)、铥(Tm)、镱(Yb)、镥(Lu)、钇(Y)等15种稀土元素的同时分析测定方法。方法检出限为0.0027~0.78μg/L,相对标准偏差为1.4%~6.3%。通过国家标准物质GBW10019苹果的准确度实验验证,测定结果均在标准证书值范围内。实验结果表明,方法适用于板栗中矿物元素及稀土元素的同时测定。     

电感耦合等离子体质谱(ICP-MS)法测定高钨基体样品中稀土元素的含量

准确测定钨矿和钨酸盐晶体等高钨基体样品中稀土元素的含量有助于开展矿床地球化学特征研究及钨酸盐激光晶体材料的制备和性质研究。在高钨基体样品电感耦合等离子体质谱法（ICP-MS）分析时,为了考察高钨及高含量阳离子等基体组成对分析结果的影响,实验针对Na2WO4、CaWO4、NaY(WO4)2、MnWO4和(Fe,Mn)WO4等高钨基体样品,采用硝酸和氢氟酸高压密闭消解,加入稀土元素并用2% HNO3溶液稀释定容配制成稀土元素浓度为1 ng·g-1的基体匹配标准溶液;同时,直接用2% HNO3溶液配制稀土元素浓度相同的非基体匹配标准溶液以对比系统考察两种基体溶液中稀土元素的相对灵敏度系数（RSC）差异。结果显示,基体匹配溶液与2% HNO3溶液中稀土元素的RSC相对偏差基本小于15%,表明基体效应的影响可以忽略不计。进而,为了准确测定常见高钨基体样品中稀土元素的含量,实验建立了基于ICP-MS的高钨基体样品中稀土元素准确定量分析方法,该方法线性关系好（R2 ? 0.9997）,检出限低（0.5 ~ 27.9 pg·g-1）,准确度理想（相对误差-6.25 ~ 10.74%）。采用该方法测定了钨酸钙单晶实际样品中稀土元素的含量并将其与基体匹配法的测定结果进行比对,结果显示两者相对偏差为0.80 ~ 12.75%,说明本文所建立的分析方法可靠,能用于定量测定高钨基体样品中稀土元素的含量。     

电感耦合等离子体质谱法测定硫化物单矿物中痕量稀土元素

硫化物单矿物基体复杂,在利用电感耦合等离子体质谱仪测定其中稀土元素时,基体效应干扰严重,为准确测定其中的稀土元素,必须对样品进行分离富集。采用硝酸-氢氟酸体系溶解样品,通过Fe(OH)_3共沉淀和阴离子交换树脂(AG1-X8)去除基体元素,利用电感耦合等离子体质谱法测定稀土元素。通过测定两种国家标准物质硫化物单矿物(GBW 07267,GBW07268,GBW07270)中稀土元素来验证该方法,方法检出限为0. 003(Tm)～0. 138(Ce) ng·g~(-1),加标回收率在91%～113%之间。     

基于矿物元素指纹图谱鉴定陈皮产地的方法研究

采用电感耦合等离子体质谱法测定了新会、广西、湖南3地42批陈皮样品中51种矿物元素的含量,运用方差分析和偏最小二乘法-判别分析（PLS-DA）研究了不同产地陈皮中矿物元素的差别,以筛选得到的9种元素为溯源指标,将不同数量级矿物元素含量进行分类和系数缩放后,构建了陈皮中矿物元素的指纹图谱,并基于各产地矿物元素含量的平均值构建了新会、广西、湖南产地陈皮中矿物元素的标准指纹图谱。通过采用SPSS20.0计算18批新会陈皮矿物元素指纹图谱与其标准指纹图谱的相似度,确定新会陈皮矿物元素指纹图谱的相似度阈值为0.941,基于此阈值建立了新会陈皮的鉴别模型。采用24批样品对所建立的鉴别模型进行准确性验证,正确率为91.6%。该方法操作简单直观,满足实验分析要求,可为陈皮的产地溯源提供参考。     

白云鄂博两种稀土矿物中铕的价态

白云鄂博稀土矿床中,现已发现的稀土矿物近40种。为了开发利用该稀土资源,对矿床中稀土元素的存在形式、分布规律的研究是非常重要的。目前通常用化学方法查明稀土矿物的成份、稀土元素的配分等。用现代物理学方法研究白云鄂博稀土矿物中稀土元素的价态还较少见。我们用穆斯堡尔效应测定了白云鄂博两种稀土矿物中铕的价态。 穆斯堡尔效应是一种核物理方法,用它可以解决有关元素的价态等问题。试验     

电感耦合等离子体质谱法同时检测红枣中铅、砷、镉、汞、铜、锌和16种稀土元素

为了研究哈密、若羌和和田红枣中铅、砷、镉、汞、铜、锌和16种稀土元素的含量情况,了解红枣重金属及稀土元素摄入的风险,建立同时检测红枣中铅、砷、汞、铜、锌和16种稀土元素的方法。红枣样品用微波消解法进行样品前处理,以电感耦合等离子体质谱法测定红枣中铅、砷、镉、汞、铜、锌和16种稀土元素的含量。各元素校准曲线的相关系数均大于0.999 0,检出限为0.01~0.05μg/L。加标回收率为92.1%~105.2%,测定结果的相对标准偏差为1.2%~3.6%(n=6)。用该方法测定苹果标准物质(GBW 10019),测定值与标准值一致。该方法适用于红枣类样品中多元素污染物快速检测及风险评估,红枣样品分析结果表明铅、砷、镉、汞、铜和稀土元素在3种红枣中的含量较低,风险监测数据表明红枣中存在重金属铅、镉摄入性风险。     

微波消解电感耦合等离子体质谱法测定桃中稀土元素及其分布

以市场销售的桃为实验材料,利用微波消解电感耦合等离子体质谱法(ICP-MS)同时测定桃中稀土元素的含量。样品经过硝酸-氢氟酸-双氧水微波消解,实现了桃中16种稀土元素的测定。各元素的检出限在0.004~0.020μg·g-1之间,方法精密度在0.78%~2.96%,回收率在95.0%~106.0%之间。比较了稀土元素在果皮和果肉中的分布。结果表明,稀土元素在果皮中的含量明显高于果肉。本法快速、准确,可用于桃等水果中稀土元素的测定。     

微敞开体系石墨消解-电感耦合等离子体质谱（ICP-MS）法测定土壤中16种稀土元素

稀土元素被广泛应用于工业领域和农业生产,稀土矿产长期大量开采和广泛使用导致土壤环境中较多稀土元素累积,对农田系统中各种生物造成毒害,并威胁人类健康,建立一种准确、快速测定土壤中稀土元素的方法,对于摸清土壤中稀土污染状况十分必要。基于本课题组前期建立的微敞开消化体系,通过优化内标元素选择、消解时间、复溶方式等,构建了微敞开体系石墨消解-电感耦合等离子体质谱(ICP-MS)法测定土壤中Sc、Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu 16种稀土元素的方法。实验结果表明,最佳的样品前处理条件为高温消解375 min、消解后加入5 mL 2% HNO3溶液开盖复溶。采用Rh-Re双内标校正能降低基体效应,显著改善稀土元素测定回收率。方法中各稀土元素标准曲线均线性关系良好（R≥0.999）,方法检出限为0.006 ~ 0.02 mg/kg,定量限为0.024 ~ 0.08 mg/kg。按实验方法检测的12个国家土壤标准物质测定值与参考值一致,两个实际土壤样品中各稀土元素测定值的相对标准偏差（RSD）在1.6% ~5.2%。方法步骤少、时间短,且正确度和精密度高,适用于批量土壤样品中稀土元素的检测。     

ICP发射光谱法测定独居石中十五个稀土元素

采用ICP发射光谱法对岩石、矿物进行分析,国内外已做了大量工作。本实验也采用该法对独居石中15种稀土元素进行了测定。     

新试剂N－烯丙基－N′－（氨基对苯磺酸钠）硫脲（ASATu）的合成、表征及其反应性能的研究

本文报道了新试剂Ｎ－烯丙基－Ｎ′－（氨基对苯磺醚钠）硫脲（ＡＳＡＴｕ）的合成并确定了结构。该试剂与４５种元素在不同介质中反应，仅有Ｃｕ￣（２＋）、Ａｇ￣＋、Ｂｉ￣（３＋）、Ｈｇ￣（２＋）和Ｆｅ￣（３＋）等离子产生特征性反应。实验证明，它可作为Ｃｕ￣（２＋）、Ａｇ￣＋等新的鉴定试剂；在酸性和近中性介质中测定了该试剂与稀土元素等四十多种金属元素反应的摩尔吸光系数。     

头发中无机元素分析方法及应用的研究进展

人体无机元素含量在头发中较其它体液或组织中高,易于检出。头发能够存储较长的时间信息,并且能提供其空间信息。通过分析其中的无机元素含量和同位素比例,可以说明元素在体内特定时间的变化以及反映人体的地理位置迁移。综述了头发中无机元素分析的前处理和仪器分析方法,重点介绍头发中无机元素分析在环境、医学及法医学研究中的应用,并对未来的技术发展和应用进行展望。     

低熟煤中常量、微量元素与煤生烃潜力参数的相关性研究

应用电离耦合等离子体原子反射光谱（ICP AES）和X射线荧光光谱（XRF），对新疆准噶尔六道湾侏罗纪低熟煤中36种微量元素的质量分数进行了测定，同时作岩石热解分析，有机碳测定，并对获取的各种数据进行回归分析，以考察它们之间的相关性。实验结果表明，除个别具有一定化学催化能力的元素外，多数常量元素及其所形成的矿物质，由于其对成煤有机物质的负增量作用，会明显降低煤的生烃潜力；微量元素对煤的生烃性能影响则较为复杂,既与其对煤的各种化学组成的有机亲和性之差异有关，亦与其在煤的大分子热裂解成烃中的某种化学催化作用有关。此外，由于某些微量元素所特有的古气候、古成煤沼泽类型的“指相”作用，亦能间接地指示煤的生烃潜力。其中Cu既是一个有着与煤的大分子物质较强亲和力的元素，又是一个可以显示古气候古成煤沼泽类型的“指相”元素，因而在指示煤的生烃潜力方面可能具有普适性。     

Impact of ageing on the distribution of platinum group elements and catalyst poisoning elements in automobile catalysts

The distribution of platinum group elements (PGEs) and catalyst poisoning elements (Pb, Zn, P and S) on the surface of gasoline and diesel automobile catalysts was investigated within this study. Laser ablation–inductively coupled plasma mass spectrometry (LA–ICPMS) provides both the sensitivity and the spatial resolution required for the surface analysis of sectioned automobile catalysts, and scanning along channels reveals the distribution of longitudinal changes in PGE and catalyst poisoning elements. Changes in catalyst surface features were studied for fresh catalysts and after ageing of the catalyst up to 80 000 km for both types of catalysts studied. The PGEs in the gasoline catalyst were found to decrease at the front of the catalyst after ageing, whereas the diesel catalyst presented a more constant loss along the catalyst. The fraction of poisoning elements (Pb, P and Zn for the gasoline catalyst and P and Zn for the diesel catalyst) retained by the catalyst is distributed non‐uniformly over the length of the catalyst. This could indicate different ageing mechanisms for gasoline and diesel catalysts. Copyright © 2003 John Wiley & Sons, Ltd.     

O-TOF-ICP-MS analysis of rare earth elements,noble elements,uranium and thorium in river-relating species

The determination of rare earth elements (REEs), Au, Pt, Ir, Pd, Th and U in various river species was performed by the orthogonal time-of-flight inductively coupled plasma mass spectrometry (o-TOF-ICP-MS). The method working conditions were optimised in order to minimise the presence and possible spectral interferences of oxides. Ratios MO⁺/M⁺ as well as interference of light REE and Ba oxides/hydroxides with high REEs were evaluated and confirmed to be insignificant. Using the internal standard Re, non-spectral matrix effects (originally decreasing of intensities up to 15%) were overcome and recoveries were found from 92 to 105% for all matrices analysed. For solutions, limits of detection (3σ) were 0.14–0.82 for REEs, Th, U and Y, 1.18 for La, 4.3–5.6 for Au, Pt, Ir and Pd 11 for Sc (all in ng L^?1). The Principal component analysis was used for classification of samples according to their places of origin successfully. The o-TOF-ICP-MS was proved to be a very sensitive and suitable technique for bio-monitoring purposes and was employed in the analysis of biota samples (fish, insect, profiles, benthal growths) originated from five different places in the river Elbe (Czech Republic).     

Energy-adjusted pseudopotentials for the rare earth elements

Nonrelativistic and quasirelativistic energy-adjusted pseudopotentials and optimized (7s6p5d)/[5s4p3d]-GTO valence basis sets for use in molecular calculations for fixed f-subconfigurations of the rare earth elements, La through Lu, have been generated. Atomic excitation and ionization energies from numerical HF, as well as SCF pseudopotential calculations using the derived basis sets, differ by less than 0.1 eV from numerical HF all-electron results. Corresponding values obtained from CI(SD), CEPA-1, as well as density functional calculations using the quasirelativistic pseudopotentials, are in reasonable agreement with experimental data.     

On books and chemical elements

The history of the classification of chemical elements is reviewed from the point of view of a bibliophile. The influence that relevant books had on the development of the periodic table and, conversely, how it was incorporated into textbooks, treatises and literary works, with an emphasis on the Spanish bibliography are analyzed in this paper. The reader will also find unexpected connections of the periodic table with the Bible or the architect Buckminster Fuller.     

Valence orbital ionization energies for second-row transition elements

Valence Orbital Ionization Energies (VOIEs) are computed from Average Configuration Energies for the elements Sr through to In. VOIEs for a specific configuration are given in the form VOIE (q) = C ₂ q ² + C ₁ q + C ₀ where q is the atomic excess charge.     

Polarized X ray fluorescence spectrometer (EDPXRF) for the determination of essential and non essential elements in tea

Polarized X ray fluorescence spectrometer (EDPXRF) is employed for the determination of essential and non essential elements in several kinds of tea marked in Italy. The quality of data was assured by calibrating the instrument with certified reference materials. The elements are found to be present in the different kinds of tea in various proportions depending on soil composition and the climate in which the plant grows.     

Speciation of oxidation states of elements by capillary electrophoresis

Progress made in the last five years in the application of capillary electrophoresis methods to chemical speciation of elements is reported on the basis of over 100 literature references. The main trends observed include development of new on‐ and off‐capillary derivatization methods, application of new detection methods, and especially coupling of CE separation systems to powerful atomic spectroscopy and mass spectrometry instruments with various ionization techniques, providing either a sensitive element‐specific detection method or a third dimension for high performance separation. Besides numerous CZE and MEKC capillary electrophoresis methods only very few examples of CE speciation with capillary electrochromatography can be found. Concerning the chemical forms of elements determined, the new procedures developed are mostly focused on redox speciation of various oxidation states of elements, metal‐bound high molecular compounds, and organometallic species.