4.Osmium (Os) Keep the following in mind when working with osmium: Os should not be exposed to any oxidizing agents to avoid the formation of OsO4. The tetroxide is very volatile and toxic. A common mistake is to dilute Os containing solutions with solutions containing nitric acid. Tetroxide formation is slow but will cause false high readings due to the increased amount of the gaseous tetroxide reaching the plasma. Only work with Os in HCl containing solutions and use a separate waste container. Check with your safety coordinator or manager before using and attempting to dispose of Os. Use glass introduction systems if at all possible when measuring Os. The washout times from plastic introduction systems are slower.
6.Arsenic (As) Avoid using dry ashing for sample preparation. Loss during sample preparation as the volatile oxide (As2O3 bp 460 ¡ãC) or chloride (AsCl3 bp 130 ¡ãC) can be avoided by performing closed vessel digestions (EPA Methods 3051 and 2052), acid digestions under reflux conditions (EPA Method 3050B, perchloric acid digestion) or by caustic fusion using either sodium carbonate or sodium peroxide/sodium carbonate fluxes. Approach ICP-OES and ICP-MS determinations with caution. ICP-OES suffers from poor sensitivity and spectral interference issues and ICP-MS from the 40Ar35Cl mass interference (other interferences include 59Co16O, 36Ar38Ar1H, 38Ar37Cl, 36Ar39K, 150Nd2+, and 150Sm2+) on the monoisotopic 75As. The use of atomic absorption using either the hydride generation or the graphite furnace techniques is very popular, although the use of 'reaction cells' that appear to eliminate the 40Ar35Cl interference in ICP-MS is an option worth exploring. 6． 砷 避免使用干灰化来制备样品。制备样品时，通过密封容器消化（EPA方法3051和2052）， 回流条件下酸消化（EPA方法3050 B, 高氯酸消化），或者使用碳酸钠或过氧化纳/碳酸钠混合物碱性熔炼 可以避免样品以挥发性的氧化物 （As2O3, 三氧化二砷 的沸点为460度）或者氯化物 （三氯化砷, 沸点 130度）的形式损失掉。 使用ICP-OES 和ICP-MS检测时要格外小心。ICP-OES的缺点是灵敏度差和光谱干扰， 而ICP-MS的缺点则是40Ar35Cl 对单一同位素的75As的质量数干扰（其它的干扰包括59Co16O, 36Ar38Ar1H, 38Ar37Cl, 36Ar39K, 150Nd2+, 和 150Sm2+）。 使用氢化物产生或者石墨熔融技术下原子吸收的应用非常普遍， 尽管使用“反应单元“来消除40Ar35Cl在使用ICP-MS时的干扰来值得去进行探索。
7.Sulfur (S) The following tips may prove useful in the preparation and solution chemistry of samples for sulfur analysis using ICP-OES: Loss during sample preparation is a significant issue. Preparations using closed vessel systems are recommended. Parr bomb fusions, Schöniger Flask combustions, and closed vessel microwave digestions should be considered depending upon the sample matrix, sulfur compound type(s), sulfur levels and sample size requirements needed to make quantitative measurements. Preparations including sulfate, Ba and Pb should be avoided. The molecular form of the sulfur may have compatibility issues with other chemical species in the sample solution preparation. Sulfate (SO4=) sulfur is a common molecular form resulting from oxidative sample preparations. Even though the preparation promises to deliver sulfite (SO3=) sulfur this species quickly air oxidizes in aqueous solution to the sulfate form. Sulfate readily precipitates with solutions containing Pb or Ba. Water soluble samples known to contain sulfur as sulfate, sulfite or low molecular weight water soluble sulfonic acids (RSO3H) may need no sample preparation but samples known to contain sulfur in other forms such as sulfides (S=), elemental (S?), polysulfides ( Sn=), thiols (RSH), organic sulfides and disulfides (R-S-R and R-S-S-R), thiolesters (R-CO-SR) etc. should undergo oxidative sample preparation to avoid possible compatibility issues with other solution components. In addition, the addition of acid to sulfide containing samples will emit H2S.
7． 硫 通常来说，硫的测定总是通过燃烧技术来进行， 而此燃烧技术与应用红外， 微库仑， 或者滴定 （碘定量）等技术来检测二氧化硫燃烧气体紧密联系， 从1974年以来， 离子色谱（形态）和-射线荧光技术大受欢迎。最近，ICP-OES已经成为一个可行的硫的测定技术， 这要归因于the availability of affordable radial view instrumentation with measurement capability in the vacuum UV spectral region and the relative freedom of spectral interferences. （这句话不知道怎么翻译好， 专业知识还是不懂，困难）。我实验室中IDLs检测的常见的发射线见表1。 表1 常见的硫发射线 发射线 IDL (光线) 发射线 IDL (光线) 142.503 .04 ng/mL 166.668 .02 ng/mL 143.328 .04 ng/mL 180.734 .07 ng/mL 147.399 .05 ng/mL 182.040 .03 ng/mL 下面的这些小技巧在使用ICP-OES分析硫时，样品的制备和溶液化学也许会有帮助。 样品制备中的样品损失是个大问题。建议在密封的容器系统中制备。可以考虑Parr 弹熔融，Schöniger瓶燃烧， 和密封容器微波消解， 可以根据样品方阵， 硫化物类型， 硫的含量及定量分析样品大小要求来选择合适的系统。 样品制备含有硫酸盐， 应避免接触钡和铅。样品制备中， 硫分子形式可能具有和其他化学品的相容性问题。硫酸盐（SO4）硫是氧化性样品制备时常见的分子形式。尽管制备过程也会形成亚硫酸盐(SO3=)硫，水溶液中此种硫很快就被空气氧化成为硫酸盐形式。溶液中含有钡和铅，硫酸盐极易沉淀。 已知含有硫的水溶性的样品，如硫酸盐， 亚硫酸盐或者低分子量的水溶性磺酸 （RSO3H） 可能不需要样品制备，但已知含有硫的其它形式，如硫化物（S=）, 元素硫，多硫化物(Sn=)，硫醇（RSH）, 有机硫化物和二硫化物，硫醇酯（R-CO-SR）等应进行氧化性样品制备, 以避免和溶液中其它组分的相容性问题。此外， 向含有硫化物的样品中加入酸将释放出H2S.
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