POWRE: Microgram to Nanogram: A Study to Reduce the Sample Size of Graphitic Carbon Targets for AMS Radiocarbon Dating

POWRE：微克到纳克：减少 AMS 放射性碳测年石墨碳靶样本量的研究

• 批准号: 9753128
• 负责人: Donna Kirner
• 金额: $ 5万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9753128&HistoricalAwards=false
• 关键词: POWRE; Microgram; Nanogram; Study; Reduce

Currently, accelerator mass spectrometry (AMS) technology provides the radiocarbon researcher with the ability to routinely measure samples of 500 micrograms to one milligram of graphitic carbon. Radiocarbon age determinations using AMS technology reduces the carbon requirement by several orders of magnitude from decay counting methods. This reduction in the required carbon sample size has allowed researchers access to samples previously not practical to measure. This study will focus on two methods to reduce the required amount of carbon for AMS radiocarbon dating in the ultra small sample range. This project has two pivotal objectives. The first objective is to optimize the processing of microgram to nanogram-sized samples of catalytically-reduced graphitic carbon for AMS radiocarbon age determinations. The second goal is to determine the most accurate way to correct 14C/13C ratios for contaminant contribution to the measured ratios of these ultra small samples. The ability to utilize AMS technology that reduces the required amount of a graphitic carbon sample to the levels of ultra small samples on a routine basis would provide the archaeological researcher with the opportunity to seek new areas of scientific inquiry. These include but are not limited to organic residues on potsherds, rock art, pollen, phytoliths, sherd temper, plant amino acids, amino acids from bone, seeds, charcoal smudges, and organic residues on tools. All of these materials are candidates for radiocarbon age determinations but the limiting factor is the extremely small amounts of organic material. Critical data from these sources could provide clues to help answer a variety of questions about human origins and prehistoric cultures. Paleontology, environmental and paleoclimatic studies and oceanography would also benefit from this research. Material that may be used for ultra small samples include amino acids in fossil bone and teeth that fall within the range of radiocarbon, chemical compounds in atmospheric aerosols, marine dissolved organic carbon and foraminifera. Each of these research areas could utilize ultra small sample technology to gather critical data and develop new areas of inquiry. The funding provided by the POWRE program opens up new avenues of research that will allow career enhancement and substantively further professional standing with the research community. Since the investigator is in a non-tenured research associate position, POWRE support may assist in her academic advancement as well. This project could provide the scientific community with a useful new tool and offers the researcher a chance to contribute in an area not ordinarily available through regular research grants.

目前，加速器质谱（AMS）技术为放射性碳研究人员提供了常规测量500微克至1毫克石墨碳样品的能力。 使用AMS技术进行放射性碳年龄测定，比衰变计数法减少了几个数量级的碳需求。 所需碳样本量的减少使研究人员能够获得以前无法测量的样本。 本研究将着重于两种方法，以减少所需的碳量AMS放射性碳测年在超小样本范围。 该项目有两个关键目标。 第一个目标是优化AMS放射性碳年龄测定中催化还原石墨碳的微克至纳克级样品的处理。 第二个目标是确定最准确的方法来校正14 C/13 C比值，以确定污染物对这些超小样品的测量比值的贡献。 利用AMS技术将石墨碳样品的所需量减少到常规的超小样品水平的能力将为考古研究人员提供寻求新的科学研究领域的机会。 这些包括但不限于陶瓷碎片、岩石艺术品、花粉、植硅石、碎片回火、植物氨基酸、来自骨骼的氨基酸、种子、木炭污迹上的有机残留物和工具上的有机残留物。 所有这些物质都是放射性碳年龄测定的候选者，但限制因素是有机物质的极少量。 来自这些来源的关键数据可以提供线索，帮助回答有关人类起源和史前文化的各种问题。 古生物学、环境和古气候研究以及海洋学也将受益于这项研究。 可用于超小样本的材料包括骨化石和牙齿中属于放射性碳范围的氨基酸、大气气溶胶中的化合物、海洋溶解有机碳和有孔虫。 这些研究领域中的每一个都可以利用超小样本技术来收集关键数据并开发新的研究领域。 由POWRE计划提供的资金开辟了新的研究途径，这将使职业生涯的提升和实质性地进一步专业地位与研究界。 由于研究者是在一个非终身研究助理的位置，POWRE的支持可能有助于她的学术进步以及。 该项目可以为科学界提供一个有用的新工具，并为研究人员提供一个机会，在一个通常无法通过定期研究赠款获得的领域作出贡献。