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Evaluation of the International Vehicle Emission (IVE) model with on-road remote sensing measurements

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Journal of Environmental Sciences 2007年第7期19卷 818-826页

作者： GUO hui ZHANG Qing-yu SHI Yao wang da-hui Institute of Environmental Engineering Zhejiang University Hang zhou 310027 China. Institute of Environmental Science Zhejiang University Hangzhou 310027 China

Intemational Vehicle Emissions （IVE） model funded by U.S. Environmental Protection Agency （USEPA） is designed to estimate emissions from motor vehicles in developing countries. In this study, the IVE model was evaluated by utilizing a dataset available from the remote sensing measurements on a large number of vehicles at five different sites in Hangzhou, China, in 2004 and 2005. Average fuel-based emission factors derived from the remote sensing measurements were compared with corresponding emission factors derived from IVE calculations for urban, hot stabilized condition. The results show a good agreement between the two methods for gasoline passenger cars＇ HC emission for all 1VE subsectors and technology classes. In the case of CO emissions, the modeled results were reasonably good, although systematically underestimate the emissions by almost 12%-50% for different technology classes. However, the model totally overestimated NOx emissions. The IVE NOx emission factors were 1.5-3.5 times of the remote sensing measured ones. The IVE model was also evaluated for light duty gasoline truck, heavy duty gasoline vehicles and motor cycles. A notable result was observed that the decrease in emissions from technology class State II to State I were overestimated by the IVE model compared to remote sensing measurements for all the three pollutants. Finally, in order to improve emission estimation, the adjusted base emission factors from local studies are strongly recommended to be used in the IVE model.

关键词： remote sensing IVE model fuel-based emission factor evaluation

Effects of N source and nitrification pretreatment on growth of Arthrospira platensis in human urine

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1846-1852页

作者： FENG dao-lun WU Zu-cheng wang da-hui Department of Environmental Science and Engineering Zhejiang University Hangzhou 310027 China

Culture ofArthrospiraplatensis （Spirulinaplatens） in human urine was investigated to get valuable biomass. NO3-N was the proper N source, in comparison with other N source, including urea, NH4-N and NO2-N. As a result, aerobic nitrification of human urine was performed, with above 93.6% nitrification percentage finally achieved with total-N （TN） load of 46.52 mg/（L.d）, in which Arthrospira platensis was successfully grown. The main compositions of the obtained biomass are close to those in Zarrouk medium. Thus, it is possible to culture Arthrospiraplatensis in nitrified human urine for food production within bioregenerative life support systems （BLSSs）.

关键词： Arthrospira platensis Human urine N source Nitrification Bioregenerative life support system (BLSS)

Science Letters:Nitrogen doping of activated carbon loading Fe_2O_3 and activity in carbon-nitric oxide reaction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 707-711页

作者： WAN Xian-kai ZOU Xue-quan SHI hui-xiang wang da-hui Institute of Environmental Engineering Zhejiang University Hangzhou 310027 China

Nitrogen doping of activated carbon loading Fe2O3 was performed by annealing in ammonia, and the activity of the modified carbon for NO reduction was studied in the presence of oxygen. Results show that Fe2O3 enhances the amount of surface oxygen complexes and facilitates nitrogen incorporation in the carbon, especially in the form of pyridinic nitrogen. The modified carbon shows excellent activity for NO reduction in the low temperature regime （〈500℃） because of the cooperative effect of Fe2O3 and the surface nitrogen species.

关键词： Activated carbon Nitric oxide Doping Iron oxides Catalytic reduction

Catalytic dechlorination of chlorobenzene in water by Pd/Fe bimetallic system

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Journal of Environmental Sciences 2003年第5期15卷 647-651页

作者： ZHOU Hong yi XU Xin hua wang da hui Department of Environmental Engineering Zhejiang UniversityHangzhou 310027China. College of Biological&Environmental Engineering Zhejiang University of TechnologyHangzhou 310032China

Catalytic reductive dechlorination of monochlorobenzene(MCB) was carried out in the palladium/iron system. With low Pd loading(0 005%), 45% dechlorination efficiency was achieved within 5 h. Pd as catalyst accelerated the reductive dechlorination reaction. Dechlorination mechanism and kinetics were discussed. The reaction took place on the bimetal surface in a pseudo first order reaction, with the rate constant being 0 0071 min -1 ( K SA =8 0×10 -3 L/(m 2·h). The reduction product for MCB was benzene.

关键词： reductive dechlorination catalytic palladium/iron chlorobenzene

2-chlorophenol oxidation kinetic by photo-ssisted Fenton process

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Journal of Environmental Sciences 2003年第4期15卷 475-481页

作者： XU Xin hua ZHAO Wei rong HUANG Yan qiao wang da hui Department of Environmental Engineering Zhejiang UniversityHangzhou 310027China.

Experimental data are presented to test and validate a kinetic model for the oxidation of 2 chlorophenol wastewater by photo assisted Fenton process. The data showed that this process had produced good effects under acidic conductions. Up to 90% 2 chlorophenol was removed after 90 minute reaction time with H 2O 2 of 25% COD Cr, in , while in UV/H 2O 2 system only 16 8% 2 chlorophenol was removed after one hour treatment. The optimal pH in this reaction occurred between pH 3 0 and pH 4.0. The reaction kinetics for photo assisted Fenton process experimented in this research was investigated. Kinetic models were proposed for the treatment of 2 chlorophenol wastewater. The reaction was found to follow the 2nd order. The equations of reaction kinetics are as follows:-d[RH]d t = K RH [RH][H 2O 2] 0exp (-K H 2O 2 t );-d[COD Cr ]d t = K COD Cr [COD Cr ][H 2O 2] 0exp(-K′ t ). The prediction of the models was found to be in a good agreement with experimental results, thus confirming the proposed reaction mechanism.

关键词： 2-chlorophenol wastewater photo assisted Fenton reagent reaction kinetic

Enhanced catalytic degradation process of o-nitrochlorobenzene by palladium-catalyzed Fe^0 particles

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Journal of Environmental Sciences 2005年第5期17卷 849-852页

作者： XU Xin-hua ZHOU Hong-yi ZHOU Mi wang da-hui Department of Environmental Engineering Zhejiang University Hangzhou 310027 China College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

Over Pd/Fe bimetallic catalyst, o-nitrochlorobenzene（o-NCB）, at a concentration of 20 mg/L in aqueous solutions, is rapidly converted to o-chloroaniline（o-CAN） first, and then quickly dechlorinated to aniline（AN） and Cl^- , without other intermediate reaction products. The aminated and dechlorinated reactions are believed to take place on the surface site of the Pd/Fe. The o-NCB removal efficiency and the next dechlorination rate increase with an increase of bulk loading of palladium and catalysts addition due to the increase of both the surface loading of palladium and the total surface area. These results indicate that reduction, amination and dechlorination of o- NCB by palladium-catalyzed Fe^0 particles, can be designed for remediation of contaminated groundwater.

关键词： palladium-catalyzed Fe^0 amination dechlornation o-NCB

Characterization of on-road CO, HC and NO emissions for petrol vehicle fleet in China city

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第7期7卷 532-541页

作者： GUO hui ZHANG Qing-yu SHI Yao wang da-hui DING Shu-ying YAN Sha-sha Institute of Environmental Engineering Zhejiang University Hangzhou 310027 China Institute of Environmental Pollution Control Technology Zhejiang University Hangzhou 310028 China

Vehicle emissions are a major source of air pollution in urban areas. The impact on urban air quality could be reduced if the trends of vehicle emissions are well understood. In the present study, the real-world emissions of vehicles were measured using a remote sensing system at five sites in Hangzhou, China from February 2004 to August 2005. More than 48000 valid gasoline powered vehicle emissions of carbon monoxide （CO）, hydrocarbons （HC） and nitrogen oxide （NO） were measured. The results show that petrol vehicle fleet in Hangzhou has considerably high CO emissions, with the average emission concentration of 2.71 %±0.02%, while HC and NO emissions are relatively lower, with the average emission concentration of （153.72±1.16）×10-6 and （233.53±1.80）×10-6, respectively. Quintile analysis of both average emission concentration and total amount emissions by model year suggests that in-use emission differences between well maintained and badly maintained vehicles are larger than the age-dependent deterioration of emissions. In addition, relatively new high polluting vehicles are the greatest contributors to fleet emissions with, for example, 46.55% of carbon monoxide fleet emissions being produced by the top quintile high emitting vehicles from model years 2000-2004. Therefore, fleet emissions could be significantly reduced if new highly polluting vehicles were subject to effective emissions testing followed by appropriate remedial action.

关键词： Remote sensing Vehicle emission Characterization

Enhanced degradation of carbon tetrachloride by surfactant-modified zero-valent iron

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第9期7卷 702-707页

作者： MENG Ya-feng GUAN Bao-hong WU Zhong-biao wang da-hui Institute of Environmental Engineering Zhejiang University. Hangzhou 310027 China

Sorption of carbon tetrachloride （CT） by zero-valent iron （ZVI） is the rate-limiting step in the degradation of CT, so the sorption capacity of ZVl is of great importance. This experiment was aimed at enhancing the sorption of CT by ZVI and the degradation rate of CT by modification of surfactants. This study showed that ZVI modified by cationic surfactants has favorable synergistic effect on the degradation of CT. The CT degradation rate of ZVI modified by cetyl pyridinium bromide （CPB） was higher than that of the unmodified ZVI by 130%, and the CT degradation rate of ZVI modified by cetyl trimethyl ammonium bromide （CTAB） was higher than that of the unmodified ZVI by 81%. This study also showed that the best degradation effect is obtained at the near critical micelle concentrations （CMC） and that high loaded cationic surfactant does not have good synergistic effect on the degradation due to its hydrophilicity and the block in surface reduction sites. Furthermore degradation of CT by ZVI modified by nonionic surfactant has not positive effect on the degradation as the ionic surfactant and the ZVI modified by anionic surfactant has hardly any obvious effects on the degradation.

关键词： Enhanced degradation Sorption Surfactants Synergistic effect Zero-valent iron (ZVI)

Hg^0 absorption in potassium persulfate solution

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第5期7卷 404-410页

作者： YE Qun-feng wang Cheng-yun wang da-hui SUN Guan XU Xin-hua Department of Environmental Engineering Zhejiang University Hangzhou 310027 China

The aqueous phase oxidation of gaseous elemental mercury (Hg0) by potassium persulfate (KPS) catalyzed by Ag+ was investigated using a glass bubble column reactor. Concentration of gaseous mercury and potassium persulfate were measured by cold vapor atom absorption (CVAA) and ion chromatograph (IC), respectively. The effects of pH value, concentration of potassium persulfate and silver nitrate (SN), temperature, Hg0 concentration in the reactor inlet and tertiary butanol (TBA), free radical scavenger, on the removal efficiency of Hg0 were studied. The results showed that the removal efficiency of Hg0 increased with increasing concentration of potassium persulfate and silver nitrate, while temperature and TBA were negatively effective. Furthermore, the removal efficiency of Hg0 was much better in neutral solution than in both acidic and alkaline solution. But the influence of pH was almost eliminated by adding AgNO3. High Hg0 concentration has positive effect. The possible reaction mechanism of gaseous mercury was also discussed.

关键词： Potassium persulfate Gaseous elemental mercury Absorption Reaction mechanism