A fully automated isotopic profile deconvoluted chromatogram (IPDC) algorithm (Fakouri Baygi et al. in Anal Chem 91:15509–15517, 2019) and user interactive HaloSeeker 1.0 (Léon et al. in Anal Chem 91:3500–3507, 2019) were compared to test... more
A fully automated isotopic profile deconvoluted chromatogram (IPDC) algorithm (Fakouri Baygi et al. in Anal Chem 91:15509–15517, 2019) and user interactive HaloSeeker 1.0 (Léon et al. in Anal Chem 91:3500–3507, 2019) were compared to test the efficacy of these two computationally enhanced non-targeted screening (CENTS) tools in isolating unknown Br/Cl compounds using high-resolution mass spectrometry (HRMS) data. HaloSeeker depends on a user to monitor the performance of the peak picking algorithm and assign molecular formulas for each isotopic signature in an ergonomic interface. Alternatively, the IPDC algorithm automatically assigns and ranks candidate molecular formulas within a set of search criteria. Both CENTS tools were evaluated using fish and sediment data acquired at 22,000 (mHRMS) and > 100,000 (uHRMS) mass resolutions, respectively. The IPDC algorithm detected 85% of compounds detected by HaloSeeker as the first candidate compound in the sediment sample, with fewer false positives. In the sediment data, the IPDC algorithm detected several compounds such as clofoctol and chlorinated paraffins that were not reported using HaloSeeker 1.0. Upon further inspection, these compounds were isolated by the HaloSeeker program, but not reported by the user. HaloSeeker detected all significant and insignificant chemical ionization products (relative to IPDC), but additional false positives were isolated in the mHRMS polychlorinated biphenyl reference standard and trout sample. HaloSeeker detected 62% of the legacy contaminant features isolated by the IPDC algorithm in the fish data (mHRMS). The comparison of these two CENTS tools demonstrates that matrix complexity and mass resolution of the HRMS platform are the key factors when choosing automated and user interactive CENTS tools.
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Research Interests: Geography, Environmental Science, Environmental Monitoring, Climate, Medicine, and 14 moreMultidisciplinary, Environmental science and technology, Great Lakes Region, Polychlorinated Biphenyls, Oxygen Fugacity, Polychlorinated Biphenyl, Air Temperature, Spatial Variation, Environmental Pollutants, Shore, Reference Values, Environmental, Lake Ontario, and Volatilization
Atmospheric size distributions for total mass, sulfate and nitrate were measured in Chicago, Illinois during the Spring, Summer, and Fall of 1994 and 1995. Nineteen samples were collected over two or three day time periods using a Wide... more
Atmospheric size distributions for total mass, sulfate and nitrate were measured in Chicago, Illinois during the Spring, Summer, and Fall of 1994 and 1995. Nineteen samples were collected over two or three day time periods using a Wide Range Aerosol Classifier ( ...
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Research Interests: Environmental Engineering, Environmental Science, Atmospheric Science, Atmospheric Aerosols, Atmospheric sciences, and 15 moreCopper, Aerosol, United States, Smelting, Zinc, Nickel, Trace Elements, Particulate Matter, STRESS CONCENTRATION FACTOR, Rural Area, Trace element, Positive Matrix Factorization, PMF, New York State, and Atmospheric Environment
Computational Fluid Dynamics (CFD) Simulation of Liquid-Liquid Mixing in Mixer Settler Mixer-settlers are widely used inmetallurgical, mineral and chemical process. One of the greatest challenges in the area of hydrometallurgy process... more
Computational Fluid Dynamics (CFD) Simulation of Liquid-Liquid Mixing in Mixer Settler Mixer-settlers are widely used inmetallurgical, mineral and chemical process. One of the greatest challenges in the area of hydrometallurgy process simulation is agitation made by impeller inside mixer-settler which yet presents one of the most common operations. Computational fluid dynamics (CFD) model has been developed to predict the effect of different physical parameters including temperature and density on the mixing characteristics of the system. It is noted that non-isotropic nature of flow in a mixer-settler, the complex geometry of rotating impellers and the large disparity in geometric scales present are some of the factors which contribute to the simulation difficulty. The experimental data for different velocity outlet was also used in order to validate the model.
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This paper will discuss that groundwater contamination from vehicular oil spills due to stormwater runoff is a major concern in highly impervious areas. This presentation examines the potential of enhanced porosity concrete (EPC) in... more
This paper will discuss that groundwater contamination from vehicular oil spills due to stormwater runoff is a major concern in highly impervious areas. This presentation examines the potential of enhanced porosity concrete (EPC) in retaining spilled oil in its pore structure. In this study EPC mixtures with porosities varying between 13-35% were examined. Known quantities of oil were introduced in different EPC specimens and rain events of different magnitudes were simulated. Oil recovered in the water that drained through the sample was quantified using a partition gravimetric method. The influence of material properties of EPC such as porosity and pore sizes, and varying environmental conditions such as rainfall intensities and rates of oil and water addition on the quantities of oil retained by the system was quantified. Using a simple geometric model for the pore system in EPC, the material parameters relevant for transport and retention are quantified. The experimental results are used to build and validate the model.
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Page 1. Fate of the detergent builder, sodium polyglyoxylate, in wastewater treatment Jae K. Park, David Jenkins, TM Holsen, TW Warnock, William E. Gledhill ABSTRACT: Laboratory-scale experiments were conducted to investigate ...
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Colloidal material in landfill leachate were separated and fractionated in size fractions. Analyses were performed to obtain the mass, elemental composition, and pollutants associated with the colloids in each fractions. The stabilization... more
Colloidal material in landfill leachate were separated and fractionated in size fractions. Analyses were performed to obtain the mass, elemental composition, and pollutants associated with the colloids in each fractions. The stabilization mechanism of the colloids is studied to evaluate their mobility potential.
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This study investigated mercury input, output, cycling, and interactions between deposition and emission at the Huntington Wildlife Forest of Newcomb, New York during 2005 and 2006. Total Hg wet deposition and deciduous throughfall were... more
This study investigated mercury input, output, cycling, and interactions between deposition and emission at the Huntington Wildlife Forest of Newcomb, New York during 2005 and 2006. Total Hg wet deposition and deciduous throughfall were collected using modified MIC-B precipitation collectors. The volume-weighted mean (VWM) total Hg concentration in throughfall (6.6 ng L-1) was higher than in precipitation (4.9 ng L-1),
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Recent investigations have found that organic chemicals may contaminate drinking water by permeating buried plastic pipes and gasket materials. Pipe-bottle direct-exposure experiments and microbalance experiments were conducted in order... more
Recent investigations have found that organic chemicals may contaminate drinking water by permeating buried plastic pipes and gasket materials. Pipe-bottle direct-exposure experiments and microbalance experiments were conducted in order to determine the susceptibility of polybutylene (PB) piping material and gasket materials to permeation by a wide range of organic chemicals. Many lipophilic compounds tested were found to permeate to a
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This study investigated mercury inputs, outputs, cycling, and the interactions between deposition, emissions and atmospheric conditions in the Huntington Forest of the Adirondacks, New York. Continuous speciated mercury concentrations of... more
This study investigated mercury inputs, outputs, cycling, and the interactions between deposition, emissions and atmospheric conditions in the Huntington Forest of the Adirondacks, New York. Continuous speciated mercury concentrations of gaseous elemental Hg (GEM), reactive gaseous Hg (RGM), and particulate Bound Hg (PBM) were made from June 2006 to May 2007. The average concentrations of GEM, RGM, and PBM were
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Electrochemical characteristics, energy consumption and material compatibility aspects of a novel process for regeneration of spent hard chromium plating baths using a Nafion-117 separator and a fuel cell cathode are discussed.... more
Electrochemical characteristics, energy consumption and material compatibility aspects of a novel process for regeneration of spent hard chromium plating baths using a Nafion-117 separator and a fuel cell cathode are discussed. Electrochemical impedance spectroscopy (EIS) and stationary polarization curves were used to characterize the performance of a fuel cell cathode in the regeneration cell. The configuration of the MEA, current
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The ‘porous pot’ has been used in the plating industry and can be classified as an electrolytic separation technique [1‐3]. Compared with other separation techniques, there are several advantages in using a porous ceramic diaphragm to... more
The ‘porous pot’ has been used in the plating industry and can be classified as an electrolytic separation technique [1‐3]. Compared with other separation techniques, there are several advantages in using a porous ceramic diaphragm to separate metal impurities from plating solutions. Theoretically, metallic impurities from the plating solutions accumulate inside the ceramic pot and can either be precipitated as
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... to develop predictive models of the energy content of municipal solid waste (MSW ... to correlate the energy content with variables derived from physical composition and ultimate analysis. ... Attempts at developing regression models... more
... to develop predictive models of the energy content of municipal solid waste (MSW ... to correlate the energy content with variables derived from physical composition and ultimate analysis. ... Attempts at developing regression models from proximate analysis data were not successful. ...
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Results from experiments using an impregnation-reduction (I-R) Pt / Nafion membrane electrode assembly (MEA) in an air fuel cell cathode to remove contaminants (Cu(II), Ni(II), and Fe(III)) from spent chromium electroplating baths are... more
Results from experiments using an impregnation-reduction (I-R) Pt / Nafion membrane electrode assembly (MEA) in an air fuel cell cathode to remove contaminants (Cu(II), Ni(II), and Fe(III)) from spent chromium electroplating baths are presented in this study. A platinum-carbon (Pt-C) / Nafion MEA and a Pb planar cathode were also used for comparison. The average removal rates of Cu(II) and Ni(II) were almost the same (0.39 and 0.40 mM hr(-1) (or 0.117 and 0.12 mmol hr(-1)), respectively) but higher than that of Fe(III) (0.16 mM hr(-1), or 0.048 mmol hr(-1)) in accordance with the Nernst-Planck flux equation. The removal rates for the same cation were independent of the cathode used. The average removal rate of each impurity was approximately proportional to the product of its initial concentration and separator area/anolyte volume ratio using Pb cathodes. Under constant current conditions the system using the Pt-C / Nafion cathode needed the highest cell voltage, about 3 V more than needed for the system with the Pt / Nafion cathode. The cell voltage required using the Pt / Nafion cathode was similar to that using the conventional planar Pb cathode. Analyses of cathode deposits by SEM/EDS and XPS techniques indicated they were minimal on the Pb and Pt / Nafion cathode and more apparent on the Pt-C / Nafion cathode. The primary deposits on the Pb cathode were chromium oxides (e.g., Cr2O3) with minor amount of lead chromate (lead dichromate or lead trichromate) and other chromium solids (Cr black). As expected, the dominant deposit on the lead anode surface was PbO2.
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... Usama M. Shahin ... The average measured dry deposition flux for HNO 3 was 3.78 ± 1.24 mg m - 2 day - 1 ; for particulate nitrate, it was 1.46 ± 0.3 mg m - 2 day - 1 ; and for ammonia gas, it was 2.64 ±1.15 mg m - 2 day - 1 . Nitrate... more
... Usama M. Shahin ... The average measured dry deposition flux for HNO 3 was 3.78 ± 1.24 mg m - 2 day - 1 ; for particulate nitrate, it was 1.46 ± 0.3 mg m - 2 day - 1 ; and for ammonia gas, it was 2.64 ±1.15 mg m - 2 day - 1 . Nitrate fluxes to the WSS and Nylasorb filter on the KSS ...
Research Interests: Environmental Engineering, Environmental Science, Water Pollution, Multidisciplinary, Environmental science and technology, and 15 moreNitrogen deposition, Nitrogen, Environmental Impact, Acid Deposition, NITRIC ACID, Molecular weight, Statistical Test, Experimental Measurement, Citric Acid, Nitrogen Dioxide, Experimental Data, Empirical Model, Sulfur Dioxide, Mass Transfer Coefficient, and Dry Deposition
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Lake trout and walleye composites were collected between 2004 and 2009 as part of the Great Lakes Fish Monitoring and Surveillance Program (GLFMSP) and analyzed for polybrominated diphenyl ethers (PBDEs). Yearly mean total PBDE... more
Lake trout and walleye composites were collected between 2004 and 2009 as part of the Great Lakes Fish Monitoring and Surveillance Program (GLFMSP) and analyzed for polybrominated diphenyl ethers (PBDEs). Yearly mean total PBDE concentrations (sum of congeners BDE-47, BDE-99, BDE-100, BDE-153, BDE-154) ranged from 44-192, 28-113, 50-107, 37-111, and 11-22 ng/g wet wt. for Lakes Michigan, Huron, Ontario, and Superior lake trout, and Lake Erie walleye, respectively. A 1980-2009 temporal record of PBDE concentrations in the Great Lakes' top predator fish (lake trout and walleye) was assembled by integrating previous GLFMSP data (1980-2003) with current results (2004-2009). Temporal profiles show obvious breakpoints between periods of PBDE accumulation and decline in trout for Lakes Huron, Michigan and Ontario with a significant (p < 0.0001 and r = 0.55, 0.72, and 0.51, respectively) decrease in concentration after 2000-2001. A similar transition was observed in Lake Superior for the nearshore site accompanied by a less significant decreasing trend (p = 0.016, r = 0.33), suggesting concentrations are declining very slowly or have leveled off. In contrast, Lake Erie walleye concentrations began leveling off in the late 1990s and no statistically significant trend (increasing or decreasing) has been observed in recent years. A decrease in the BDE-47/BDE-153 ratio was also recently observed, suggesting a transition to more highly brominated PBDEs is occurring in Great Lakes trout. This study provides region-wide evidence that PBDE concentrations are generally declining in Great Lakes trout, although there are clear exceptions to this trend. Results from this study reflect the positive impact of the 2004 PentaBDE ban on macro-scale aquatic freshwater ecosystems.
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We have studied the acute toxicity of fluoride ion to , , and juvenile . LC50 values varied with species and (due to precipitation) initial water hardness. Exposure to elevated fluoride levels in water resulted in increased blood fluoride... more
We have studied the acute toxicity of fluoride ion to , , and juvenile . LC50 values varied with species and (due to precipitation) initial water hardness. Exposure to elevated fluoride levels in water resulted in increased blood fluoride levels in . ... American Public Health ...
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A measurement program in this study has been undertaken to measure the concentrations of particles and Hg0 in rural areas of New York State during the summer of 2000 and 2001. Sampling was performed at sites in southwestern (Stockton, NY)... more
A measurement program in this study has been undertaken to measure the concentrations of particles and Hg0 in rural areas of New York State during the summer of 2000 and 2001. Sampling was performed at sites in southwestern (Stockton, NY) and northern New York (Potsdam, NY) where these materials may be transported into the New York from the central United States and from Canada. The data from these measurements were used in paired receptor models to assess the origins of the measured concentrations. Factor analysis in the form of positive matrix factorization (PMF) was used to obtain information about possible sources of the aerosol. Six and seven sources were resolved from Stockton and Potsdam sites, respectively. Six of the sources are common to the two sites in these two summers. They are secondary sulfate, secondary nitrate, soil, wood smoke, zinc smelter and copper smelter. A nickel smelter source is also resolved at Potsdam. Potential source contribution function (PSCF) analysis which combines the aerosol data with the air parcel backward trajectories was applied to identify possible source areas and pathways from these sources at the two sites. The combination of the two receptor modeling methods, PMF and PSCF, provides an effective way in identifying atmospheric aerosol sources and their likely locations. Emissions from different anthropogenic activities as well as secondary aerosol production are the main source measured in Potsdam and Stockton.
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... AND MEASURED WITH A SMOOTH SURFACE FOR TOTAL PARTICLE MASS, LEAD AND CALCIUM IN CHICAGO JuI-MIN LIN, GUOR-CHENG FANG, THOMAS M ... 0.098 8.802 22/10/91-23/10/91 1777 100.0 267.2 -- -- * Plates were exposed when there was no rain or... more
... AND MEASURED WITH A SMOOTH SURFACE FOR TOTAL PARTICLE MASS, LEAD AND CALCIUM IN CHICAGO JuI-MIN LIN, GUOR-CHENG FANG, THOMAS M ... 0.098 8.802 22/10/91-23/10/91 1777 100.0 267.2 -- -- * Plates were exposed when there was no rain or threat ...
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Over the past fifteen years, a number of intensive field campaigns and measurement networks have provided valuable information on the estimated rates of mercury wet deposition to sensitive ecosystems throughout the world. In contrast, the... more
Over the past fifteen years, a number of intensive field campaigns and measurement networks have provided valuable information on the estimated rates of mercury wet deposition to sensitive ecosystems throughout the world. In contrast, the ability to place bounds on the rates of mercury dry deposition has been hampered by the relative lack of direct measurements of this process. Recently,