Thomas C. Ho

Lamar University, Beaumont, Texas, United States

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Publications (27)55.53 Total impact

  • Ziyuan Wang, Qiang Xu, Thomas C. Ho
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    ABSTRACT: To conduct a well-planned plant shutdown, so as to reduce flare emissions for the sake of plant profitability and local environmental sustainability, one of the primary tasks is to perform comprehensive and precise accountings for flare emissions. Since the literature is still lacking systematic and quantitative studies, plant-wide dynamic simulations are employed to simulate an ethylene plant shutdown and characterize its flare emission sources through which dynamic emission profiles of various emission species changing with respect to time are obtained. Plant shutdown emission inventories are enriched with details for point emission sources, and possible technical supports are provided to both industry and environmental agencies on evaluating and developing cost-effective flare minimization strategies in the future.
    Chemical Engineering & Technology 05/2014; · 1.37 Impact Factor
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    ABSTRACT: We have demonstrated that magnetic carbon nanocomposite fabrics prepared by microwave assisted heating are advanced adsorbents in the removal of Cr(VI) with a much higher removal capacity of 3.74 mg g−1 compared to 0.32 mg g−1 for cotton fabrics and 0.46 mg g−1 for carbon fabrics. The enhanced Cr(VI) removal is attributed to the highly porous structure of the nanocomposites. The adsorption kinetics follow the pseudo-second-order model, which reveals a very large adsorption capacity and high adsorption rate. The removal process takes only 10 min, which is much faster than conventional adsorbents such as activated carbon and biomass that often requires hours of operation. The significantly reduced treatment time and the large adsorption capacity make these nanocomposite fabrics promising for the highly efficient removal of heavy metals from polluted water.
    J. Mater. Chem. A. 01/2014; 2(7).
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    ABSTRACT: Magnetocapacitance mechanism in supercapacitor is revealed as combination of giant magnetoresistance (GMR) electrode and Lorentz force induced electrolyte convection.
    Nano Energy. 01/2014;
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    ABSTRACT: Chemical facilities, where large amounts of chemicals and fuels are processed, manufactured, and housed, are at high risk to originate air emission events, including intensive flaring and toxic gas release caused by various uncertainties such as equipment failure, false operation, natural disaster, or terrorist attack. Based on an available air-quality-monitoring network, to detect the possible emission sources (chemical plants) for an observed emission event, so as to support diagnostic and prognostic decisions in a timely and effective manner, a systematic method for abnormal emission identifications should be employed. In this article, a systematic methodology for such applications has been developed. It includes two stages of modeling and optimization work: (1) the determination of background normal emission rates from multiple emission sources and (2) multiobjective optimization for emission-source identification and quantification. This method not only can determine emission source location, starting time, and time duration responsible for an observed emission event, but can also estimate in reverse the dynamic emission rate and total emission amount from an accidental emission source. It provides valuable information for investigations of accidents and root-cause analysis for emission events; meanwhile, it helps evaluate the regional air-quality impact caused by such emission events as well. Case studies including the detection of a real SO2 emission event are employed to demonstrate the efficacy of the developed methodology.
    Industrial & Engineering Chemistry Research. 06/2013; 52(26):9189–9202.
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    ABSTRACT: Contrary to the helical carbon structure from pure cotton fabrics under microwave heating and radical oxidized ignition of nanoparticles from conventional heating, magnetic carbon tubular nanocomposite fabrics decorated with uniformly dispersed Co-Co(3)O(4) nanoparticles were successfully synthesized via a microwave heating process using cotton fabric and inorganic salt as precursors, which have shown better anti-corrosive performance and demonstrated great potential as novel electrochemical pseudocapacitor electrode.
    Nanoscale 02/2013; · 6.73 Impact Factor
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    ABSTRACT: Magnetic carbon nanostructures from microwave assisted- and conventional-pyrolysis processes are compared. Unlike graphitized carbon shells from conventional heating, different carbon shell morphologies including nanotubes, nanoflakes and amorphous carbon were observed. Crystalline iron and cementite were observed in the magnetic core, different from a single cementite phase from the conventional process.
    Chemical Communications 11/2012; · 6.38 Impact Factor
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    ABSTRACT: A waste-free process to recycle Fe@Fe2O3/polypropylene (PP) polymer nanocomposites (PNCs) is introduced to synthesize magnetic carbon nanocomposites (MCNCs) and simultaneously produce useful chemical species which can be utilized as a feedstock in petrochemical industry. The magnetic nanoparticles (NPs) are found to have an effective catalytic activity on the pyrolysis of PP. The PNCs (with a NP loading of 20.0 wt%) undergo a complete degradation with 2 h pyrolysis at 500 °C in a H2/Ar atmosphere and the degradation components exhibit a distribution of species with different numbers of carbon, while only 40% of pure PP is decomposed after applying the same pyrolytic conditions. The coked solid waste from the conventional process has been utilized as a carbon source to form a protective carbon shell surrounding the magnetic NPs. The magnetic carbon nanocomposites (MCNCs) pyrolyzed from PNCs containing 20.0 wt% NPs demonstrate extremely fast Cr(VI) removal from wastewater with the almost complete removal of Cr(VI) within 10 min. The pH effect on the Cr(VI) removal efficiency is investigated with a preferable value of 1–3. The adsorbent exhibits much higher adsorption capacity in acidic solutions than that in alkali solutions. The large saturation magnetization (32.5 emu g−1) of these novel magnetic carbon nanocomposites allows fast recycling of both the adsorbents and the adsorbed Cr(VI) from the liquid suspension in a more energetically and economically sustainable way by simply applying a permanent magnet. The significantly reduced treatment time required to remove the Cr(VI) makes these MCNCs promising for the efficient removal of the heavy metals from wastewater. Kinetic investigation reveals the pseudo-second-order adsorption of Cr(VI) on these novel magnetic carbon nanocomposite adsorbents.
    RSC Advances 05/2012; 2(11):4844-4856. · 3.71 Impact Factor
  • Jie Fu, Chuanyu Zhao, Qiang Xu, Thomas C. Ho
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    ABSTRACT: Multistage material-handling (MSMH) processes are broadly possessed by industries for manufacturing massive amounts of workpieces (jobs), where hoists are usually employed by following certain movement schedules based on the job-processing recipes. In this paper, we consider a common situation that an existing MSMH production line has reached its maximum productivity; in order to debottleneck the production and increase its productivity, some units will be retrofitted to increase their job-processing capacity under a fixed budget. Under this situation, which units need to be retrofitted and how many additional capacities will be added to those retrofitted units have to be optimally determined. Correspondingly, since process design has changed, the hoist schedule also needs to be adjusted. Apparently, the best way to deal with such an MSMH debottleneck problem requires the consideration of both the process retrofit and hoist rescheduling at the same time. In this paper, an MILP (mixed integer linear programming) based model is developed to simultaneously identify the best retrofit design and hoist schedule to obtain the maximum productivity under a fixed retrofit budget. On the basis of this development, different retrofit and hoist-scheduling scenarios under different budgets can also be examined, so that the Pareto frontier balancing both retrofit investment and productivity can be identified, which will provide the comprehensive decision support for an MSMH debottleneck problem. The efficacy of the proposed methodology has been demonstrated by case studies.
    Industrial & Engineering Chemistry Research. 04/2012; 52(1):123–133.
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    ABSTRACT: The electrical switching and electrochromic phenomena of nanocomposites comprising poly(p-phenylenebenzobisthiazole) (PBZT) and tungsten oxide (WO3) nanoparticles have been investigated as a function of the nanoparticle loading. Both dissolving PBZT and doping PBZT backbone structure with acid are achieved by one simple step. Chlorosulfonic acid (CSA) is used as a solvent and spontaneously transformed to sulfuric acid upon exposure to moisture. The formed sulfuric acid serves as doping agent to improve the electrical conductivity of PBZT. The most significant enhancement of electrical switching is observed in the nanocomposites with low weight fraction (5%). The electrical conductivity of 5% WO3/PBZT nanocomposite thin film is increased by about 200 times and 2 times, respectively, as compared to those of the as-received PBZT and PBZT/CSA thin films within the scanning voltage range from -1.0 V to -0.5 V. As the nanoparticle loading increases to 20% and 30%, the nanocomposites follow ohmic conduction mechanism. Stable electrical conductivity switching has been observed before and after applying a bias on the pristine PBZT and WO3/PBZT nanocomposite thin films. Electrochromic phenomena of both pristine PBZT and WO3/PBZT nanocomposite thin films with high contrast ratio have been observed after applying a bias (3 V). The mechanisms of the nanoparticles in enhancing the electrical switching and electrochromic properties are proposed in this work. References: 1)J Zhu; S Wei; M Jr. Alexander; D Cocke; TC Ho; Z Guo; "Electrical Conductivity Manipulation and Switching Phenomena of Poly(p-phenylenebenzobisthiazole) Thin Film by Doping Process" Journal of Materials Chemistry. 2010, 20, 568. 2)J Zhu, S Wei, M Jr Alexander, T D Dang, TC Ho, Z Guo; "Enhanced Electrical Switching and Electrochromic Properties of Poly(p-phenylenebenzobisthiazole) Thin Films Embedded with Nano-WO3"Advanced Functional Materials,2010, 18, 3076-3084.
    Advanced Functional Materials 09/2010; 20(18):3076 - 3084. · 10.44 Impact Factor
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    ABSTRACT: Volatile organic compound (VOC) emissions from various sources such as chemical process industry, manufacturing industry, and automobiles have been an environmental and health concern. With the emerging emphasis on using green technologies to minimize greenhouse gas emissions, the use of microwave energy to achieve VOC emissions control with its electric power coming from nongreenhouse-related energy sources, such as wind, geothermal, solar, or even nuclear energy, becomes an attractive option. In this study, an experimental investigation involving the use of microwave energy to accomplish high temperature destruction of p-xylene in a packed bed reactor was performed using a SiC (silicon carbide) foam as the microwave absorbing media with air or nitrogen being the carrier gas. The experimental facilities consisted of a gas cylinder, a mass flow controller, a p-xylene vaporizer, a packed bed reactor packed with a SiC foam, a microwave applicator, and a gas chromatograph/mass spectrometer (GC/MS) for gas analysis. The SiC was found to be an excellent microwave absorber, which efficiently converts the microwave energy into heat energy. It was observed that the SiC temperature rises rapidly upon microwave irradiation and reaches a steady state temperature of higher than 800 °C within 2−3 min depending on the experimental conditions. A semiempirical energy balance model was formulated to describe the dynamic temperature profiles of the SiC in the reactor, and the model was found to simulate the observed profiles reasonably well. The destruction and removal efficiencies (DREs) for p-xylene were observed to reach 100% for all the experiments conducted with air being the carrier gas; however, the DREs never reached 100% with nitrogen being the carrier gas and the major destruction byproducts were observed to be benzene, toluene, styrene, biphenyl, and the unreacted p-xylene. The study has demonstrated that the microwave technology can be effectively developed to control the emissions of low concentrations of VOCs, especially in air.
    Industrial & Engineering Chemistry Research - IND ENG CHEM RES. 08/2010;
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    ABSTRACT: East Asia is the largest source region of global anthropogenic mercury emissions, and contributes to atmospheric mercury concentration and deposition in other regions. Similarly, mercury from the global pool also plays a role in the chemical transport of mercury in East Asia. Annual simulations of atmospheric mercury in East Asia were performed using the STEM-Hg modeling system to study the mass budgets of mercury in the region. The model results showed strong seasonal variation in mercury concentration and deposition, with signals from large point sources. The annual mean concentrations for gaseous elemental mercury, reactive gaseous mercury and particulate mercury in central China and eastern coastal areas were 1.8 ng m(-3), 100 pg m(-3) and 150 pg m(-3), respectively. Boundary conditions had a strong influence on the simulated mercury concentration and deposition, contributing to 80% of the concentration and 70% of the deposition predicted by the model. The rest was caused by the regional emissions before they were transported out of the model domain. Using different oxidation rates reported for the Hg(0)-O(3) reaction (i.e., by Hall, 1995 vs. by Pal and Ariya, 2004) led to a 9% difference in the predicted mean concentration and a 40% difference in the predicted mean deposition. The estimated annual dry and wet deposition for East Asia in 2001 was in the range of 590-735 Mg and 482-696 Mg, respectively. The mercury mass outflow caused by the emissions in the domain was estimated to be 681-714 Mg yr(-1). This constituted 70% of the total mercury emission in the domain. The greatest outflow occurred in spring and early summer.
    Science of The Total Environment 07/2010; 408(16):3277-91. · 3.26 Impact Factor
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    ABSTRACT: Iron oxide (α-phase) nanoparticles with coercivity larger than 300 Oe have been fabricated at a mild temperature by an environmentally benign method. The economic sodium chloride has been found to effectively serve as a solid spacer to disperse the iron precursor and to prevent the nanoparticles from agglomeration. Higher ratios of sodium chloride to iron nitrate result in smaller nanoparticles (19nm for 20:1 and 14nm for 50:1). The presence of polyvinyl alcohol (PVA) limits the particle growth (15nm for 20:1 and 13nm for 50:1) and favors nanoparticle dispersion in polymer matrices. Obvious physicochemical property changes have been observed with PVA attached to the nanoparticle surface. With PVA attached to the nanoparticle surface, the nanoparticles are found not only to increase the PVA cross-linking with an increase in melting temperature but also to enhance the thermal stability of the PVA. The nanoparticles are observed to be uniformly dispersed in the polymer matrix. Scanning electron microscopy (SEM) microstructure also shows an intermediate phase with a strong interaction between the nanoparticles and the polymer matrices, arising from the hydrogen bonding between the PVA and hydroxyl groups on the nanoparticle surface. The addition of nanoparticles favors the cross-linkage of the bulk PVA matrices, resulting in a higher melting temperature, and an enhanced thermal stability of the polymer matrix. KeywordsNanoparticles-Polymer nanocomposites-Thermal properties
    Journal of Nanoparticle Research 01/2010; 12(7):2415-2426. · 2.18 Impact Factor
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    ABSTRACT: Current–voltage (i-v) characteristics of dry poly(p-phenylenebenzobisthiazole) (PBZT) thin films are studied before and after various doping processes. Conductivity switching phenomenon is observed after doping with HCl and H2SO4 acidic solutions at different concentration levels. The conductivity is 10 folds higher in a relatively high sweeping voltage range (0.2–0.3 V) than that sweeping in a lower range of 0–0.1 V. The conductivity switching phenomenon becomes more obvious with an increase of acid concentration. HCl shows to be more favorable for a quick and efficient switching behavior than H2SO4. The reduction of PBZT with metal (Fe, Cu and Pd) doping process produces linear conductivity along the whole sweeping range of voltage. A 30% electrical conductivity enhancement is observed after applying an external dc voltage on the acid soaked PBZT film and different voltages enhance the conductivity to the same level. The conductivity returns gradually after removing the applied voltage. Four-point probe conductivity measurements, FT-IR, scanning electron microscopy, EDAXelemental analysis, X-ray diffraction and TGA thermal analysis were used for better understanding the doping processes and conductivity switching mechanisms. A molecular structure transformation during the doping process is proposed.
    Journal of Materials Chemistry 01/2010; 20(3). · 5.97 Impact Factor
  • Thomas C. Ho, Tsao-Jen Lin
    Journal of The Taiwan Institute of Chemical Engineers - J TAIWAN INST CHEM ENG. 01/2009; 40(6):593-594.
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    ABSTRACT: Wall-flow diesel particulate filters (DPFs) are considered the most effective devices for the control of diesel particulate emissions. A requirement for the reliable operation of the DPFs, however, is the periodic and/or continuous regeneration of the filters. While microwave heating has been considered a potential active regeneration method for the DPFs, past studies on the technology have identified several technical problems leading to filter failure. The problems are mainly associated with the use of inappropriate filter materials for the microwave system and the generation of local hotspots due to uneven microwave heating, resulting in the physical damage to the filters. The objective of this study was to develop and demonstrate the technology employing a microwave-absorbing filter material coupled with an effective waveguide design for the reliable regeneration of DPFs. In this study, a well-equipped diesel emission control laboratory was established to conduct the experiments. The experimental facilities included a 6-kWe diesel generator, an exhaust flow control system, a diesel particulate filter system, a microwave energy supply system, a soot sampling system, a differential-pressure measurement system, and a temperature measurement system. The DPF was a silicone carbide wall-flow monolith filter enclosed in a quartz filter holder. A commercial 1.4-kWe microwave oven was modified to accommodate the quartz holder and a waveguide was engineered to evenly supply the microwave energy to the enclosed filter to achieve filter regeneration. In the experiments, the diesel engine exhaust was lined up to flow through the filter with a fixed flow rate. The microwave regeneration was triggered after a specific amount of soot loading was reached based on the differential pressure drop reading. The results have indicated that the designed system has been able to achieve uniform temperature profiles both in the radial and the vertical DPF positions. The off-line regeneration of DPF by microwave energy has been observed to be highly efficient in terms of energy consumption and regeneration efficiency. The DPM filtration efficiency has remained comparably high after 150 cycles of filtration/regeneration with no apparent physical damage to the DPF being observed. The on-line microwave regeneration of the DPF, however, is not as efficient as the off-line regeneration due to the insufficient oxygen concentration in the engine exhaust stream.
    Industrial & Engineering Chemistry Research - IND ENG CHEM RES. 10/2008; 48(1).
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    ABSTRACT: In this study, the model response in terms of simulated mercury concentration and deposition to boundary condition (BC), initial condition (IC), model grid resolution (12 km versus 36 km), and two alternative Hg(II) reduction mechanisms, was investigated. The model response to the change of gaseous elemental mercury (GEM) concentration from 0 to 2 ng m−3 in IC/BC is found to be very linear (r2>0.99) based on the results of sensitivity simulations in July 2001. An increase of 1 ng m−3 of GEM in BC resulted in an increase of 0.81 ng m−3 in the monthly average of total mercury concentration, and 1270 ng m−2 in the monthly total deposition. IC has similar but weaker effects compared to those of BC. An increase of 1 ng m−3 of GEM in IC resulted in an increase of 0.14 ng m−3 in the monthly average of total mercury concentration, and 250 ng m−2 in the monthly total deposition. Varying reactive gaseous mercury (RGM) or particulate mercury (PHg) in BC/IC has much less significant impact. Simulation results at different grid resolutions show good agreement (slope=0.950–1.026, r=0.816–0.973) in mercury concentration, dry deposition, and total deposition. The agreement in wet deposition is somewhat weaker (slope=0.770–0.794, r=0.685–0.892) due to the difference in emission dilution and simulated precipitation that subsequently change reaction rates in the aqueous phase. Replacing the aqueous Hg(II)-HO2 reduction by either RGM reduction by CO (5×10−18 cm3 molecule−1 s−1) or photoreduction of RGM (1×10−5 s−1) gives significantly better model agreement with the wet deposition measured by Mercury Deposition Network (MDN). Possible ranges of the reduction rates are estimated based on model sensitivity results. The kinetic estimate requires further verification by laboratory studies.
    Atmospheric Environment 03/2008; · 3.11 Impact Factor
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    ABSTRACT: In this study, we present the response of model results to different scientific treatments in an effort to quantify the uncertainties caused by the incomplete understanding of mercury science and by model assumptions in atmospheric mercury models. Two sets of sensitivity simulations were performed to assess the uncertainties using modified versions of CMAQ-Hg in a 36-km Continental United States domain. From Set 1 Experiments, it is found that the simulated mercury dry deposition is most sensitive to the gaseous elemental mercury (GEM) oxidation product assignment, and to the implemented dry deposition scheme for GEM and reactive gaseous mercury (RGM). The simulated wet deposition is sensitive to the aqueous Hg(II) sorption scheme, and to the GEM oxidation product assignment. The inclusion of natural mercury emission causes a small increase in GEM concentration but has little impact on deposition. From Set 2 Experiments, it is found that both dry and wet depositions are sensitive to mercury chemistry. Change in model mercury chemistry has a greater impact on simulated wet deposition than on dry deposition. The kinetic uncertainty of GEM oxidation by O3 and mechanistic uncertainty of Hg(II) reduction by aqueous HO2 pose the greatest impact. Using the upper-limit kinetics of GEM–O3 reaction or eliminating aqueous Hg(II)–HO2 reaction results in unreasonably high deposition and depletion of gaseous mercury in the domain. Removing GEM–OH reaction is not sufficient to balance the excessive mercury removal caused by eliminating the HO2 mechanism. Field measurements of mercury dry deposition, better quantification of mercury air-surface exchange and further investigation of mercury redox chemistry are needed for reducing model uncertainties and for improving the performance of atmospheric mercury models.
    Atmospheric Environment. 10/2007;
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    ABSTRACT: Clouds can significantly affect photochemical activities in the boundary layer by altering radiation intensity, and therefore their correct specification in the air quality models is of outmost importance. In this study we introduce a technique for using the satellite observed clouds to correct photolysis rates in photochemical models. This technique was implemented in EPA's Community Multiscale Air Quality modeling system (CMAQ) and was tested over a 10 day period in August 2000 that coincided with the Texas Air Quality Study (TexAQS). The simulations were performed at 4 and 12 km grid size domains over Texas, extending east to Mississippi, for the period of 24 to 31 August 2000. The results clearly indicate that inaccurate cloud prediction in the model can significantly alter the predicted atmospheric chemical composition within the boundary layer and exaggerate or underpredict ozone concentration. Cloud impact is acute and more pronounced over the emission source regions and can lead to large errors in the model predictions of ozone and its by-products. At some locations the errors in ozone concentration reached as high as 60 ppb which was mostly corrected by the use of our technique. Clouds also increased the lifetime of ozone precursors leading to their transport out of the source regions and causing further ozone production down-wind. Longer lifetime for nitrogen oxides (NOx = NO + NO2) and its transport over regions high in biogenic hydrocarbon emissions (in the eastern part of the domain) led to increased ozone production that was missing in the control simulation. Over Houston-Galveston Bay area, the presence of clouds altered the chemical composition of the atmosphere and reduced the net surface removal of reactive nitrogen compounds. Use of satellite observed clouds significantly improved model predictions in areas impacted by clouds. Errors arising from an inconsistency in the cloud fields can impact the performance of photochemical models used for case studies as well as for air quality forecasting. Air quality forecast models often use the model results from the previous forecast (or some adjusted form of it) for the initialization of the new forecast. Therefore such errors can propagate into the future forecasts, and the use of observed clouds in the preparation of initial concentrations for air quality forecasting could be beneficial.
    Journal of Geophysical Research 01/2007; 112. · 3.17 Impact Factor
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    ABSTRACT: Emission inventory is one of the required inputs to air quality models. To assist in the urban and regional modeling efforts, United States Environmental Protection Agency (EPA) has compiled a National Emission Inventory (NEI) for criterion pollutants, and the precursors of ozone and particulate matter (PM). In December 2002, EPA released the 1999 NEI estimates (NEI99), which represent the most recent national emission data. However, the data sets are not in model-ready format for air quality simulations. This present work converts the NEI99 Final Version 2 data sets into Inventory Data Analyzer (IDA) format and processes the data using the Sparse Matrix Operator Kernel Emissions (SMOKE) modeling system to generate a gridded emission inventory in a domain covering the west Gulf Coast Region, USA. The spatial and diurnal emission characteristics of the gridded emission inventories are then assessed and compared with those of the National Emission Trend 1996 (NET96). The NEI99 database contains more complete emission records in both area and point sources. It is also found that NEI99 data exhibit greater emissions with respect to point and mobile sources but smaller emissions with respect to area sources when compared to the corresponding gridded NET96 data in the same study domain. The most distinct differences between the NEI99 and NET96 databases are CO emission of mobile sources, SO2 emissions of point sources, and VOC/PM/NH3/NOx emissions of area and non-road sources. The gridded NEI99 data show low VOC/NOx ratios (<2-5) in the urban areas of the study domain.
    Journal of Environmental Management 07/2005; 75(4):303-13. · 3.06 Impact Factor
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    ABSTRACT: Air pollutant emission is one of the predominant factors affecting urban air quality such as ground-level ozone formation. This paper assesses the impact of changing emission inventory scenarios, based on combinations of point, mobile, area/non-road and biogenic sources, on the tropospheric ozone concentration in two southeast Texas urban areas, i.e. Houston-Galveston and Beaumont-Port Arthur, during the rapid ozone formation event (ROFE) on August 25, 2000. The EPA's Community Multiscale Air Quality (CMAQ) modeling system with 1999 national emission inventory (NEI99) estimates and updated SAPRC99 chemical mechanism are used in the sensitivity analysis for twelve different emission scenarios. Based on model results, it is found that the point source emission of NOx and VOC contributes the greatest ozone peak in the ROFE. Removing Texas point sources of VOC and NOx emission from the inventory results in a reduction in peak O3 concentration by 128 and 70 ppbv in Houston urban area, respectively. Similar but less drastic impact from point source is also observed in the Beaumont-Port Arthur area. The effect on peak ozone concentration due to mobile, area and non-road sources emissions are less significant compared to that of point source emission. Reducing VOC emission appears to be more effective than reducing NOx emission in lowering peak O3 concentration in the studied region. Although biogenic emission can contribute up to 37 ppbv of peak ozone level over a large area, the affected area is away from the urban region of concern, and should not be the main cause for O3 non-attainment in the two urban areas. Removing CO emission from mobile sources does not lead to significant reduction (< 1 ppbv) in ozone concentrations. The modeled data also show that the transport of O3 precursors from adjacent states can cause a significant ozone plume near Beaumont due to its proximity to the state border based on the conditions during the August 25, 2000 O3 episode.
    Journal of Environmental Management 07/2005; 75(4):315-23. · 3.06 Impact Factor

Publication Stats

107 Citations
55.53 Total Impact Points

Institutions

  • 2005–2014
    • Lamar University
      • • Department of Chemical Engineering
      • • Department of Chemistry and Biochemistry
      • • Department of Civil Engineering
      Beaumont, Texas, United States
  • 2009
    • National Chung Cheng University
      Chia-i-hsien, Taiwan, Taiwan