An Automated 15N, 13C Analyzer for the University of Texas Marine Science Institute, Port Aransas, Texas

建议为德克萨斯大学海洋科学研究所购买15N，13C自动分析仪，以取代已有25年历史的同位素比质谱仪和相关的高真空样品制备线。尽管使用目前的系统分析了数以万计的样品，但该系统目前无法操作，需要进行重大检修。然而，由于该系统的年龄、相对原始的技术以及几个用户的需求，对该仪器的任何维修都不太可能在长期内具有成本效益，也不太可能满足研究所科研人员的期望。相反，购买一台新的分析仪代表着技术能力的实质性进步，这将为研究所的科学家开辟更多的研究途径，并为目前资助的研究项目提供同位素数据。拟议的和目前得到资助的研究途径包括微生物学、生态学、生理学和化学研究。这项研究将利用C和N等生物活性元素的稳定同位素组成来描绘代谢途径，了解自然环境中的食物网，并确定这些元素在生态系统中的来源、转化和命运。拟议的分析仪是一种紧凑的仪器，只需最少的样品准备即可确定气体、固体和液体在其自然状态下的碳和氮同位素比率。该系统避免了在高真空线上进行昂贵和耗时的样品制备，并随后将纯化的样品气体转移到质谱仪，因为样品处理和同位素分析集成在一个单元中。与研究所科学家目前可用的系统相比，拟议系统的另一个优势是，可以在一个仪器上分析示踪剂研究中使用的自然丰度为13C和15N的样品以及经过同位素修正的样品。

Purchase of an automated 15N, 13C analyzer for the University of Texas Marine Science Institute to replace a 25 year old isotope ratio mass spectrometer and associated high vacuum sample preparation lines is proposed. Although tens of thousands of samples have been analyzed using the present system, it is currently inoperable and requires a major overhaul. However, because of the system's age, its relatively primitive technology, and demand by several users, any repairs to the instrument are unlikely to be cost effective over the long term or meet the expectations of the scientific research staff at the Institute. Instead, the purchase of a new analyzer represents a substantial advance in technological capabilities which will open additional avenues of research for the scientists at the Institute as well as providing isotopic data for currently funded research programs. The proposed and currently funded research avenues include microbiological, ecological, physiological and chemical studies. This research will use the stable isotope compositions of bioactive elements, such as C and N, to delineate metabolic pathways, understand food webs in natural environments, and determine the sources, transformations and fates of these elements in ecosystems. The proposed analyzer is a compact instrument which determines the carbon and nitrogen isotopic ratios of gases, solids and liquids in their natural state with minimal sample preparation. Expensive and time consuming sample preparation on high vacuum lines with subsequent transfer of purified sample gases to a mass spectrometer is avoided in the proposed system since sample processing and isotopic analysis are integrated into one unit. An additional advantage of the proposed system over those presently available to Institute scientists is that samples with natural abundance of the 13C and 15N isotopes as well as isotopically amended samples used in tracer studies can be analyzed on one instrument.