The Radiocarbon Laboratory of the Fluminense Federal University was installed in 2009, and its NEC Single Stage Accelerator Mass Spectrometry system has been operational since 2012. As the first 14C-AMS facility in Latin America, the LAC-UFF became a reference center for radiocarbon (14C) dating in Brazil. Over the years we have implemented pretreatment protocols for several kinds of materials, such as cellulose, soil, bone, and biofuels. In the present paper we describe our current protocols for the preparation of these types of samples. Moreover, after 10 years of operation, with the aim of expanding the range of materials we are able to analyze, we report the results of several tests to improve accuracy, precision and background levels. For example, here we discuss how isotopic fractionation during the graphitization and measurement steps has been controlled. Concerning results interpretation, our research group has been using OxCal chronological models to analyze different contexts such as stromatolite growth, tree rings, soil deposition and marine reservoir effect (MRE) determination.

中文翻译：

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LAC-UFF 状态报告：当前协议和近期发展

Fluminense 联邦大学放射性碳实验室于 2009 年安装，其 NEC 单级加速器质谱系统自 2012 年开始运行。作为第一个14在拉丁美洲的 C-AMS 设施中，LAC-UFF 成为放射性碳的参考中心（14C) 在巴西约会。多年来，我们已经为纤维素、土壤、骨骼和生物燃料等多种材料实施了预处理方案。在本文中，我们描述了我们目前用于制备这些类型样品的协议。此外，经过 10 年的运营，为了扩大我们能够分析的材料范围，我们报告了几项测试的结果，以提高准确性、精密度和背景水平。例如，我们在这里讨论如何控制石墨化和测量步骤中的同位素分馏。关于结果解释，我们的研究小组一直在使用 OxCal 时间模型来分析不同的背景，例如叠层石生长、树木年轮、土壤沉积和海洋水库效应 (MRE) 测定。