Development and Deployment of Autonomous and Remotely Operated Chemical Sensor System: Integrated Laboratory and Field Studies of Seafloor Hydrothermal Vent Fluids

自主远程操作化学传感器系统的开发和部署：海底热液喷口流体的综合实验室和现场研究

• 批准号: 1434798
• 负责人: Kang Ding
• 金额: $ 48.59万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1434798&HistoricalAwards=false
• 关键词: Development; Deployment; Autonomous; Remotely; Operated

This project involves the continued development, integration, and application of chemical sensor systems that can be used autonomously to monitor key components in hydrothermal vent fluids at mid-ocean ridges. Hydrothermal vent fluids play a key role in the Earth sciences in helping to maintain ocean chemistry, while also providing chemicals essential for the origin and evolution of the spectacular communities of organisms associated with deep sea vents- now and in the ancient geological past. Here the investigators identify an integrated program of technical modifications and laboratory and vent related studies that will enhance the effectiveness of chemical sensor data for interpretation of deep-sea hydrothermal vent systems. The investigation will contribute to the enhancement of research infrastructure that will be available to ocean scientists and engineers involved in research and training in a wide range of disciplinary areas. Collaboration with colleagues in engineering at the University of Michigan and Zhejiang University in China has broadened participation in ocean science research and has allowed the investigators to apply recent advances in nanotechnology, micromachining, and process control software and hardware in developing concepts needed for the next generation of autonomous chemical sensor systems. Development of chemical sensors with autonomous operation capabilities is also important as progress is being made with fiber-optic cabled ocean observatories, which will provide power for instruments on the seafloor and ultimately at deep-sea vents, facilitating longer term measurements and unattended operation. Moreover, the research will benefit from the participation of undergraduate students in connection with the NSF Research Experiences for Undergraduates (REU) program - Fluids in the Earth. Graduate students at the University of Minnesota will also participate in the research. Indeed undergraduate and graduate students have worked with the investigators on sensor applications and participated in oceanographic research cruises, while playing a key role in the deployment on the seafloor of chemical sensors and vent fluid sampling systems that they helped to create.Redox and pH represent master variables in all geochemical and biological systems. Thus, this research focuses on enhancing the measurement of these parameters for longer times and over a greater range of temperatures. Accordingly, the objectives are as follows: (1) Extend the autonomous in-situ calibration module to include redox components (e.g., dissolved H2S); (2) Replace conventional ceramic sensor for pH measurement with a functionally similar device composed of nano-ceramic, potentially enhancing measurements at lower temperatures with less frequent need for calibration. Recent advances in nanotechnology and microelectronics now make this possible; (3) Couple electrochemical sensor systems with newly developed hydrothermal fluid samplers for sensor triggered autonomous acquisition of hydrothermal fluid. By coupling the sensor system with a fluid sampling system, the investigators will achieve an instrument that combines event detection with event response; (4) Perform network (internet, LAN) tests of refined automation protocols; (5) Integrate lab and field calibration and verification measurements with deployments at seafloor hydrothermal vents in the Eastern Pacific ocean. The researchers have considerable experience at this vent system, and the data obtained will contribute to both technical and scientific objectives; and, (6) Conduct high-temperature lab experiments using a newly designed flow reactor adapted with ceramic-based pH sensors. These studies permit testing of recent predictions of elevated pH values at near critical conditions based on earlier pH (in-situ) data measured at the seafloor.

该项目涉及继续开发、集成和应用化学传感器系统，这些系统可以自动用于监测大洋中脊的热液喷口流体中的关键成分。热液喷口流体在地球科学中发挥着关键作用，有助于维持海洋化学，同时也提供了与深海喷口有关的壮观生物群落的起源和演化所必需的化学物质--无论是现在还是在古代地质过去。在这里，调查人员确定了一个综合方案，其中包括技术改进以及实验室和喷口相关研究，这些方案将提高化学传感器数据在解释深海热液喷口系统方面的有效性。这项调查将有助于加强研究基础设施，供参与广泛学科领域研究和培训的海洋科学家和工程师使用。与密歇根大学和浙江大学在中国的工程学同事的合作扩大了对海洋科学研究的参与，并使研究人员能够应用纳米技术、微加工和过程控制软件和硬件的最新进展来开发下一代自主化学传感器系统所需的概念。具有自主操作能力的化学传感器的开发也很重要，因为光纤连接的海洋观测站正在取得进展，这将为海底和最终深海喷口的仪器提供电力，促进长期测量和无人值守的操作。此外，这项研究将受益于本科生参与NSF本科生研究体验(REU)计划-地球流体。明尼苏达大学的研究生也将参与这项研究。事实上，本科生和研究生在传感器应用方面与研究人员合作，并参与了海洋学研究巡航，同时在他们帮助创建的化学传感器和喷口流体采样系统的海底部署中发挥了关键作用。氧化还原和pH值代表着所有地球化学和生物系统的主变量。因此，本研究的重点是在更长的时间和更大的温度范围内加强这些参数的测量。因此，目标如下：(1)扩展自主现场校准模块，以包括氧化还原成分(如溶解的硫化氢)；(2)用由纳米陶瓷组成的功能类似的装置取代用于酸碱度测量的传统陶瓷传感器，潜在地增强较低温度下的测量，而不需要频繁地进行校准。纳米技术和微电子技术的最新进展使这一点成为可能；(3)将电化学传感器系统与新开发的热液流体采样器结合起来，用于传感器触发的热液流体自动采集。通过将传感器系统与流体采样系统相结合，调查人员将实现一种将事件检测与事件响应相结合的仪器；(4)对改进的自动化协议进行网络(互联网、局域网)测试；(5)将实验室和现场校准和核查测量与部署在东太平洋海底热液喷口的工作相结合。研究人员在这个通风系统方面有相当丰富的经验，所获得的数据将有助于实现技术和科学目标；以及，(6)使用新设计的流动反应器进行高温实验室实验，该反应器配备了基于陶瓷的pH传感器。通过这些研究，可以根据在海底测量的早期pH值(就地)数据，检验最近对近临界条件下pH值升高的预测。