{"id":12,"date":"2021-08-12T06:16:50","date_gmt":"2021-08-12T06:16:50","guid":{"rendered":"https:\/\/sites.chapman.edu\/envgeo\/?page_id=12"},"modified":"2021-08-12T06:16:50","modified_gmt":"2021-08-12T06:16:50","slug":"research","status":"publish","type":"page","link":"https:\/\/sites.chapman.edu\/envgeo\/research\/","title":{"rendered":"Research"},"content":{"rendered":"<p>The Environmental Geochemistry Lab conducts research in a number of areas.\u00a0 Please read on to learn about various ongoing projects in the lab; contact\u00a0<a title=\"mailto:cskim@chapman.edu?subject=Research in the Environmental Geochemistry Lab\" href=\"mailto:cskim@chapman.edu?subject=Research%20in%20the%20Environmental%20Geochemistry%20Lab\">Dr. Christopher Kim<\/a>\u00a0for more information.<\/p>\n<hr \/>\n<h3 style=\"text-align: center\">Heavy Metal Sequestration by Iron Oxyhydroxide Nanoparticles<\/h3>\n<p><a href=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/nanoparticles-copy.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-108 alignleft\" src=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/nanoparticles-copy.jpg\" alt=\"\" width=\"158\" height=\"180\" data-wp-editing=\"1\" \/><\/a><\/p>\n<p class=\"paragraph_style_2\">Iron oxyhydroxides are among the most common and reactive natural phases found in the environment with respect to metal uptake.\u00a0 Increasingly, particles at the nanometer (10<span class=\"style_1\">-9<\/span>\u00a0m) scale have been recognized as having chemical and physical properties that vary dramatically relative to larger particles.\u00a0 Thus, the study and manipulation of these nanoparticles for remediative purposes can improve our understanding of natural environmental processes and inform future technologies to enhance metal removal from contaminated aqueous systems.\u00a0 Projects in this area include:<\/p>\n<ul>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Concentration- and pH-based metal uptake onto nanoparticles as a function of size<br \/>\n<\/span><a href=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/Picture1.png\"><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-106 alignright\" src=\"https:\/\/sites.chapman.edu\/envgeo\/envgeo\/files\/2021\/09\/Picture1-300x217.png\" alt=\"\" width=\"270\" height=\"195\" srcset=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/Picture1-300x217.png 300w, https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/Picture1.png 418w\" sizes=\"auto, (max-width: 270px) 100vw, 270px\" \/><\/a><\/p>\n<\/li>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Heavy metal structural incorporation into nanoparticles with aging at elevated temperatures<br \/>\n<\/span><\/p>\n<\/li>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Aggregation of and metal uptake on nanoparticles as a function of pH and ionic strength<br \/>\n<\/span><\/p>\n<\/li>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Effects of drying and freezing on nanoparticle aggregation and metal uptake<\/span><\/p>\n<\/li>\n<\/ul>\n<hr \/>\n<h3 style=\"text-align: center\">Characterizing the Speciation, Distribution, and Correlation of Heavy Metals in Mine Wastes<\/h3>\n<p class=\"paragraph_style_2\">Decades of mining in California have left a legacy of metal-contaminated mine wastes across the world\u2019s mineralized regions.\u00a0 These wastes often contain elevated levels of many hazardous metals in addition to the primary ore metal.\u00a0 Understanding trends in metal concentrations, metal speciation (the dominant chemical form of the metal), and correlations between metals as afunction of particle size will provide insight into the mechanical and chemical processes that distribute metals in the environment and impact their availability to living organisms.<\/p>\n<p><a href=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_0485-copy.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-105 alignright\" src=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_0485-copy.jpg\" alt=\"\" width=\"239\" height=\"178\" \/><\/a><\/p>\n<p class=\"paragraph_style_2\">Collaborations with individuals at the\u00a0<a title=\"http:\/\/www.usgs.gov\" href=\"http:\/\/www.usgs.gov\">US Geological Survey\u00a0<\/a>and the\u00a0<a title=\"http:\/\/www.blm.gov\" href=\"http:\/\/www.blm.gov\">Bureau of Land Management<\/a>\u00a0allow access to sites for sampling, with size separation conducted at Chapman.\u00a0 Further analysis involves techniques available at X-ray synchrotron facilities, which can provide detailed structural and chemical information at relatively low concentrations.<\/p>\n<p>&nbsp;<\/p>\n<hr \/>\n<h3 class=\"paragraph_style_1\" style=\"text-align: center\"><span class=\"style\">Metal Availability in Mine Wastes Through Leach Studies<\/span><\/h3>\n<p class=\"paragraph_style_2\">While total metal concentration is an important factor in assessing the hazard level of a contaminated waste, it is the fraction that can be leached, or removed from the solid phase and mobilized in solution, that may largely dictate the bioavailability of the metal in natural systems.\u00a0\u00a0 Lab-based leaching tests can help assess such availability, with different size fractions of previously-separated mine waste exposed to different solutions to simulate surface water interactions and human ingestion\/inhalation.\u00a0 Currently leach tests are underway with the following leachates:<\/p>\n<p><a href=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_7692.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-109 alignright\" src=\"https:\/\/sites.chapman.edu\/envgeo\/envgeo\/files\/2021\/09\/IMG_7692-225x300.jpg\" alt=\"\" width=\"203\" height=\"270\" srcset=\"https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_7692-225x300.jpg 225w, https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_7692-768x1024.jpg 768w, https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_7692-1152x1536.jpg 1152w, https:\/\/sites.chapman.edu\/envgeo\/wp-content\/uploads\/sites\/18\/2021\/09\/IMG_7692.jpg 1440w\" sizes=\"auto, (max-width: 203px) 100vw, 203px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<ul>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Deionized water<br \/>\n<\/span><\/p>\n<\/li>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Simulated gastric fluid (SGF)<br \/>\n<\/span><\/p>\n<\/li>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Simulated lung fluid (SLF)<br \/>\n<\/span><\/p>\n<\/li>\n<li class=\"full-width\">\n<p class=\"paragraph_style_3\"><span class=\"style_2\">Phagolysosomal simulate fluid (PSF)<\/span><\/p>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>The Environmental Geochemistry Lab conducts research in a number of areas.\u00a0 Please read on to learn about various ongoing projects in the lab; contact\u00a0Dr. Christopher Kim\u00a0for more information. Heavy Metal Sequestration by Iron Oxyhydroxide Nanoparticles Iron oxyhydroxides are among the most common and reactive natural phases found in the environment with respect to metal uptake.\u00a0 [&hellip;]<\/p>\n","protected":false},"author":37,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-12","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/pages\/12","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/users\/37"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/comments?post=12"}],"version-history":[{"count":0,"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/pages\/12\/revisions"}],"wp:attachment":[{"href":"https:\/\/sites.chapman.edu\/envgeo\/wp-json\/wp\/v2\/media?parent=12"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}