Acquisition and Development of Two ICP Instruments: Continuous Ice Core Elemental Analyses and Other Environmental Applications

在大气、水文、地球、生态系统和人类学的研究中，沙漠研究所（DRI）的教师、科学家和学生经常需要量化微量元素和同位素。DRI的四极电感耦合等离子体质谱计（ICP-MS）被广泛用于此类测量，但该仪器的检测限不足以满足许多项目。因此，主要研究人员已经申请资助两个新的ICP仪器：Finnigan MAT Element2高分辨率，双聚焦ICP- ms和瓦里安Vista-Pro轴向观察电感耦合等离子体光学发射光谱仪（ICP- oes）。还要求追加经费用于仪器研制，以便将这两种ICP仪器纳入DRI最近开发的冰芯连续微量元素和同位素分析方法。美国国家科学基金会（nsf）资助的美国冰芯工作组（us Ice Core Working Group）明确指出，持续提高高分辨率能力是美国冰芯研究继续发展的优先要求。考虑到收集和储存冰芯的高成本，以及它们在大范围的时空尺度上提供关于过去大气化学、大气和海洋环流以及人为污染的非常详细的信息的潜力，很明显，为冰芯分析提供最好的分析程序和仪器是必要的。DRI教员最近开发了一种新颖、高效的方法，使用ICP-MS对冰芯上的微量元素和化学物质进行连续、高分辨率和精确的共登记测量。在格陵兰岛Summit约135米(M)的岩心上对15种化学物质和元素的测量，以及使用南极洲simple Dome岩心开发的试验数据，证明了这种新方法的潜力，以及DRI四轴ICP-MS的局限性。在冰芯中，一些重要元素和同位素的浓度低于四极ICP-MS的检出限。这个问题也阻碍了其他环境科学应用，在这些应用中，元素和同位素数据是回答关键问题的基础。虽然该提案的主要目标是显著提高美国冰芯研究的水平和范围，但最先进的ICP-MS和ICP-OES的可用性将提高和扩大DRI和内华达州大学和社区学院系统（UCCSN）在其他领域(例如，污染气溶胶对降水的影响，地下水指纹，确定地表水中胶体物质的来源，微量元素分析（考古学）。特别是，作为内华达州唯一能够专门进行高分辨率元素和同位素分析的ICP-MS， Element2 ICP-MS的收购将吸引新的教职员工加入DRI和UCCSN系统（目标是增加多样性），并改善和扩大全州研究生和本科生培训的机会。

OPP-0216552McConnellFaculty, scientists, and students of the Desert Research Institute (DRI) routinely need to quantify trace elements and isotopes in their research in atmospheric, hydrologic, earth, ecosystem, and anthropological sciences. DRI's quadrapole inductively coupled plasma mass spectrometer (ICP-MS) is widely used for such measurements, but the detection limits of this instrument are inadequate for many projects. Therefore, the Principal Investigators have requested funding for two new ICP instruments: a Finnigan MAT Element2 high-resolution, double focusing ICP-MS and a Varian Vista-Pro axially viewed inductively coupled plasma optical emission spectrometer (ICP-OES) under the Major Research Instrumentation (MRI) Program. Additional funds are requested for instrument development to incorporate the two ICP instruments into DRI's recently developed method for continuous trace element and isotope analyses in ice cores. Continual improvement of high-resolution capabilities specifically was identified by the NSF-sponsored U.S. Ice Core Working Group as a priority requirement for the continuation of U.S. ice core research. Given the high cost of collecting and storing ice cores and their potential to provide highly detailed information on past atmospheric chemistry, atmospheric and oceanic circulation, and anthropogenic pollution across a wide range of temporal and spatial scales, it is clear that the best possible analytical procedures and instrumentation for ice core analyses are warranted. DRI faculty has recently developed a novel, efficient method using ICP-MS to make continuous, high-resolution and exactly co-registered measurements of trace elements and chemical species on ice cores. Measurements of 15 chemical species and elements on a ~135 meter (M) core from Summit, Greenland, and pilot data developed using cores from Siple Dome, Antarctica, demonstrate the potential of this new approach as well as the limitations of DRI's quadrapole ICP-MS. In ice cores, the concentrations of some important elements and isotopes are below the detection limits of the quadrapole ICP-MS. This problem also hinders other environmental science applications where elemental and isotope data are fundamental to answering critical questions. While a major objective of this proposal is to significantly advance the level and scope of U.S. ice core research, the availability of a state-of-the-art ICP-MS and ICP-OES will improve and expand research capabilities for DRI and University and Community College System of Nevada (UCCSN) faculty working in other fields (e.g., impact of pollution aerosols on precipitation, groundwater fingerprinting, determination of sources of colloidal material in surface waters, trace element analysis in archeology). In particular, as the only ICP-MS in Nevada capable of dedicated, high-resolution elemental and isotopic analyses, the acquisition of the Element2 ICP-MS will attract new faculty to DRI and the UCCSN system (with a goal of increasing diversity) as well as improve and expand opportunities for graduate and undergraduate student training throughout the state.