Chongxuan Liu

Diffusion of ions and electron shuttles into grain-scale mineral coatings

Lead Institution

Lawrence Berkeley National Laboratory

Principal Investigator

James Davis

Project type

Exploratory Research

Important reactive phenomena that affect the transport and fate of many elements and contaminants in the subsurface occur at the mineral-water interface, including sorption and electron transfer…

Model Development on Using Clay Membranes for Arsenic Removal from Drinking Water

Lead Institution

University of Missouri - Columbia

Principal Investigator

Baolin Deng

Project type

Exploratory Research

Use of clay membranes for arsenic removal from drinking water has been explored at the University of Missouri-Columbia, supported by a CAREER grant from the National Science Foundation. Arsenic is a…

Influence of Reactive Transport on the Reduction of U(VI) in the Presence of Fe(III) and Nitrate (Liu NABIR-Fe/U, PNNL Scope #42331)

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Exploratory Research

To examine in sediment-containing experimental systems (packed columns) the reduction of U(VI) by metal-reducing bacteria in a simulated groundwater medium. Work authorization text added 08/11/05:…

Influence of calcium on aqueous U(VI) speciation and U(VI) sorption to the Hanford sediments

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Exploratory Research

Uranium (VI) is a ubiquitous contaminant at Hanford and other DOE sites, resulting from its central role in the nuclear fuel cycle. In-ground migration of uranium (VI) at Hanford, WA, and other DOE…

Interactions Between Fe(III) - Reducing Bacteria and Fe Oxides: Microbial and Geochemical Dissolution Controls (Zachara BES-oxide), PNNL Scope #28036)

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

Project type

Exploratory Research

Investigate electron transfer mechanisms involved in bacterial Fe(III) oxide reduction. Work authorization text added 08/11/05: Fe(III) oxides poise the oxidation/reduction potential of…

U(VI) speciation and its influence on microbial reduction in presence of humic substances

Lead Institution

Oak Ridge National Laboratory

Principal Investigator

Baohua Gu

Project type

Exploratory Research

This study is to investigate aqueous U(VI) speciation in presence of humic substances (HS) and its influence on microbial uranyl reduction. Our experimental results indicated that HS enhances the…

Mineralogic Residence and Desorption Rates of Sorbed 90Sr in Contaminated Subsurface Sediments: Implications to Future Behavior and In-Ground Stability
(Zachara EMSP-Sr, PNNL Scope #40896)

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

Project type

Exploratory Research

Define the mineralogic residence and intraparticle distribution of 137Cs in sediments contaminated with two different high-level waste (HLW) types, and to define the relationships of residence and…

Characterization of U(VI) Sorption-Desorption Processes and Model Upscaling (Zachara, EMSP-U, PNNL Scope #43914)

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

Project type

Exploratory Research

Develop experimental data, process-level models, and up-scaling approaches to improve capabilities to model U(VI) transport in heterogeneous vadose zone and groundwater plumes.

The Role of Microenvironments and Physicochemical Subsurface Components on Field Scale Biogeochemistry and Contaminant Mobility

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James McKinley

Project type

Exploratory Research

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL. The research proposed will resolve critical Hanford and basic subsurface science…

Cr(VI) removal from aqueous solution using a commercial activated carbon coated with quaternized poly(4-vinylpyridine)

Lead Institution

University of Missouri - Columbia

Principal Investigator

Baolin Deng

Project type

Exploratory Research

In this study, a polymeric adsorbent (GAC-QPVP) was prepared by quaternizing and coating poly(4-vinylpyridine) on a commercial activated carbon (F400, Calgon). Batch experiments showed that the…

Pore-scale Carbon Biogeochemical Processes in Soils and Their Impact to Climate Models

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Exploratory Research

Carbon (C) flux from terrestrial soils is an important component in Earth System Models (ESMs) to simulate global carbon cycling and its effect on climate changes. One major challenge to reliably…

NMR microscopy of diffusive transport in natural porous mineral grains

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Capability Research

We propose further 1H NMR studies of water-saturated natural porous mineral granules in order to investigate fluid transport in these materials. Previous significant distortions due to the…

Influence of Mass transfer on Bioavailablility and Kinetic Rate of U(VI) Biotransformation (Liu NABIR-U, PNNL Scope # 45386. Liu NABIR.)

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Exploratory Research

Enhance our understanding on the mechanisms that influence uranium bioavailability and kinetic rate of biotransformation in contaminated sediments.

NMR microscopy of diffusive transport in natural porous mineral grains

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Capability Research

We propose to employ comparative 1H and 19F NMR diffusion studies to investigate the transport processes and interactions of ionic salts with clay suspensions.

Influence of Microscopic Mass Transfer on the Reactivity and Stability of Uranium

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Exploratory Research

This proposed project will investigate microscopic U(VI) mass transfer under influence of biogeochemical reactions in representative Hanford U(VI)-contaminated sediments. Recent research by our group…

Microscale and spectroscopic investigations in geochemical and microbiological systems

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

Project type

Large-Scale EMSL Research

Apply experimental manipulation and field investigations to understanding the behavior of selected chemical and microbial components in natural systems. The research is targeted towards compounds…

Role of Microenvironments and Transition Zones in Subsurface Reactive Contaminant Transport

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James McKinley

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL. The research proposed will resolve critical Hanford and basic subsurface science…

Microscopic Mass Transfer on U(VI) and Tc(VIII) in Subsurface sediments

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Limited Scope

This project will investigate microscopic mass transfer process and its influence on and coupling with geochemical and biogeochemical reactions in subsurface sediments. The research will focus on…

Microbial CH4 and CO2 Fluxes and C Stabilization Mechanisms in Soils

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Vanessa Bailey

Project type

Large-Scale EMSL Research

Current versions of the Community Land Model (CLM) do not represent the soil biogeochemical mechanisms controlling the fluxes of CO2 and CH4, two known greenhouse gases (GHG).. This failure is…

Microscopic Mass Transfer of U and Tc in Subsurface Sediments

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Exploratory Research

This project will investigate microscopic mass transfer process and its influence on and coupling with geochemical and biogeochemical reactions in subsurface sediments. The research will focus on…

Role of Microenvironments and Transition Zones in Subsurface Reactive Contaminant Transport

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James McKinley

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL. The research proposed will resolve critical Hanford and basic subsurface science…

Role of Microenvironments and Transition Zones in Subsurface Reactive Contaminant Transport

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James McKinley

Project type

Exploratory Research

The PNNL Scientific Focus Area (SFA) will resolve critical Hanford and basic subsurface science issues through integrated, multi-disciplinary, science-theme focused research on the role of…

Hydro-Biogeochemical Process Dynamics in the Groundwater-Surface Water Interaction Zone

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL.PNNL Scientific Focus Area. The PNNL SFA will develop a predictive understanding…

Microscopic characterization of porosity, diffusivity, and tortuosity in single particles of Hanford sediments using Nuclear Magnetic Resonance (NMR) Technique

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Chongxuan Liu

Project type

Capability Research

Our recent characterization of uranium(VI) speciation and physical location in 30-year contaminated Hanford Site sediments demonstrated that uranium(VI) primarily resides as U(VI)-silicate…

Hydro-Biogeochemical Process Dynamics in the Groundwater-Surface Water Interaction Zone

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL.PNNL Scientific Focus Area. The PNNL SFA will develop a predictive understanding…

Impacts of Pore Scale Heterogeneity on Nanoparticle Motility and Transport: A Micromodel Study

Lead Institution

ExxonMobil Research and Engineering

Principal Investigator

Changyong Zhang

Project type

Exploratory Research

The increasing production, application and disposal of functionalized nanomaterials will inevitably lead to wide environmental impacts. Motility and transport of nanoparticles in the subsurface…

Pore- to Core-Scale Research to Inform Ecosystem-Scale Soil C Biogeochemistry

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Vanessa Bailey

Project type

Large-Scale EMSL Research

The spatial separation of soil organic carbon (SOC), microbes, and extracellular activity is an important mechanism of SOC protection in soils that exists at the soil pore (micron-mm) scale. The…

Role of Microenvironments and Transition Zones in Field scale microbial ecology and biogeochemistry

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James McKinley

Project type

Exploratory Research

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL. The research proposed will resolve critical Hanford and basic subsurface science…

Microbial CH4 and CO2 Fluxes and C Stabilization Mechanisms in Soils -- supplement to Proposal 47865

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Vanessa Bailey

Current versions of the Community Land Model (CLM) do not represent the soil biogeochemical mechanisms controlling the fluxes of CO2 and CH4, two known greenhouse gases (GHG).. This failure is…

Role of Microenvironments and Transition Zones in Field Scale Microbial Ecology and Biogeochemistry

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James McKinley

Project type

Limited Scope

This is a renewal proposal for a previous collaborative effort between the PNNL Scientific Focus Area (SFA) and EMSL. The research proposed will resolve critical Hanford and basic subsurface science…

Projects