Photochemical Reactions of Particulate Mercury Species at the Water-Particle Interface in Aquatic Environments

水生环境中水颗粒界面处颗粒汞物质的光化学反应

• 批准号: 1905239
• 负责人: Yong Cai
• 金额: $ 42.42万
• 依托单位: Florida International University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1905239&HistoricalAwards=false
• 关键词: Photochemical; Reactions; Particulate; Mercury; Species

In this project, Drs. Yong Cai, Guangliang Liu, and Kevin O'Shea at the Florida International University are funded by the Environmental Chemical Sciences Program of the NSF Division of Chemistry to study the reactions of mercury (Hg) that is associated with particles in aquatic environments. These particulate Hg species (pHg) are very common in natural waters, and they are often thought of as unreactive and not very mobile. However, they do react under the influence of sunlight (photochemical reactions) and need to be considered for an accurate description of Hg cycling, especially the air-water exchange of Hg. This project aims to provide a basic understanding of these photochemical reactions and explore the role of pHg in the air-water Hg exchange. The project has a broad range of benefits to research, education, and outreach at a Hispanic Serving Institution. It provides training for PhD and undergraduate students. Underrepresented minority students gain research experience. The curriculum development of the unique Environmental Chemistry-focused PhD track program is being enhanced. The project also promotes public awareness on Hg contamination and health risks. Since the aquatic particles are semiconducting and photosensitizing in nature, the investigators focus on the photochemical reactions of pHg involving electron-hole pairs and reactive oxygen species. They define the reaction pathways of pHg phototransformations and quantify the kinetics of photochemical reduction of oxidized Hg species and the oxidation of elemental pHg. They also study the mechanisms related to the pHg photoreactions. Experiments using model iron, titanium, and manganese oxide particles of different band gap energies and field-collected particles are combined with quantum chemistry calculations. The bandgap energies analysis uses spectrometric measurements. Particle chemical composition and optical properties are determined using inductively coupled plasma mass spectrometry (ICP-MS) and scanning electron microscopy (SEM). The analysis of elemental and oxidized Hg in the dissolved and particulate phases is based on an isotope dilution, purge and trap, thermal desorption, and ICP-MS method. The research is expected to clarify the involvement of pHg species in Hg photochemical transformation and the role in air-water Hg exchange.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在这个项目中，佛罗里达国际大学的蔡勇、刘光亮和凯文·奥谢博士受到美国国家科学基金会化学部环境化学科学计划的资助，研究与水环境中的颗粒物有关的汞(Hg)的反应。这些颗粒汞物种(PHG)在自然水域中非常常见，它们通常被认为是不活跃的，流动性不大。然而，它们确实在阳光(光化学反应)的影响下发生反应，需要考虑才能准确地描述汞的循环，特别是汞的空气-水交换。本项目旨在提供对这些光化学反应的基本了解，并探索PHG在空气-水汞交换中的作用。该项目对西班牙裔服务机构的研究、教育和推广有广泛的好处。它为博士和本科生提供培训。未被充分代表的少数民族学生获得了研究经验。独特的以环境化学为重点的博士学位课程的课程开发正在得到加强。该项目还提高了公众对汞污染和健康风险的认识。由于水生粒子在自然界中具有半导性和光敏性，研究人员主要关注PHG的涉及电子-空穴对和活性氧物种的光化学反应。它们定义了PHG光转化的反应路径，定量了氧化的汞物种的光化学还原动力学和元素PHG的氧化动力学。他们还研究了与PHG光反应有关的机理。使用不同带隙能和场收集粒子的模型铁、钛和锰氧化物粒子的实验与量子化学计算相结合。带隙能量分析使用光谱测量。用电感耦合等离子体质谱(ICPMS)和扫描电子显微镜(SEM)测定了颗粒的化学组成和光学性质。采用同位素稀释、吹扫捕集、热解吸、电感耦合等离子体质谱等方法对溶解和颗粒相中的元素汞和氧化态汞进行分析。这项研究预计将澄清PHG物种在汞光化学转化中的参与以及在空气-水汞交换中的作用。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Speciation of thioarsenicals through application of coffee ring effect on gold nanofilm and surface-enhanced Raman spectroscopy

• DOI: 10.1016/j.aca.2020.01.042
• 发表时间: 2020-04-15
• 期刊: ANALYTICA CHIMICA ACTA
• 影响因子: 6.2
• 作者: Liamtsau, Valery;Fan, Changjun;Cai, Yong
• 通讯作者: Cai, Yong

Removal of As(III) from Water Using the Adsorptive and Photocatalytic Properties of Humic Acid-Coated Magnetite Nanoparticles

• DOI: 10.3390/nano10081604
• 发表时间: 2020-08-01
• 期刊: NANOMATERIALS
• 影响因子: 5.3
• 作者: Phuong Pham;Rashid, Mamun;O'Shea, Kevin
• 通讯作者: O'Shea, Kevin

Application of dimensional analysis in sorption modeling of the styryl pyridinium cationic dyes on reusable iron based humic acid coated magnetic nanoparticles

量纲分析在苯乙烯基吡啶鎓阳离子染料在可重复使用的铁基腐殖酸包覆磁性纳米粒子吸附建模中的应用

• DOI: 10.1016/j.chemosphere.2021.131699
• 发表时间: 2022
• 期刊: Chemosphere
• 影响因子: 8.8
• 作者: Esmaeilian, Anahita;O'Shea, Kevin E.
• 通讯作者: O'Shea, Kevin E.