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Influence of Chemical Oxygen Demand Concentrations on Anaerobic Ammonium Oxidation by Granular Sludge From EGSB Reactor

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Biomedical and Environmental Sciences 2006年第3期19卷 192-196页

作者： JING KANG jian-long wang Laboratory of Environmental Technology INET Tsinghua University Beijing lO0084 China

Objective To investigate the effect of chemical oxygen demand （COD） concentrations on the anaerobic ammonium oxidation （ANAMMOX）. Methods An Expanded Granular Sludge Bed （EGSB） reactor was used to cultivate the granular sludge and to perform the ANAMMOX reaction in the bench scale experiment. NH4^＋-N and NO2^--N were measured by using colorimetric method. NO3^＋-N was analyzed by using the UV spectrophotometric method. COD measurement was based on digestion with potassium dichromate in concentrated sulphuric acid. Results When the COD concentrations in the reactors were 0 mg/L, 200 mg/L, 350 mg/L, and 550 mg/L, respectively, the NH4^＋-N removal efficiency was 12.5%, 14.2%, 14.3%, and 23.7%; the removal amount of NO2-N was almost the same; the nitrate removal efficiency was 16.8%, 94.5%, 86.6%, and 84.2% and TN removal efficiency was 16.3%, 50.7%, 46.9%, and 50.4%, moreover, the COD removal efficiency was 85%, 65.7%, and 60%; the COD removal rate was 27.42, 61.88, and 97.8 mg COD/（h·L）. Conclusion COD concentrations have a significant influence on anaerobic ammonium oxidation by granular sludge.

关键词： Anaerobic ammonium oxidation Granular sludge Nitrogen removal COD

Characteristics of Zn^(2+) Biosorption by Saccharomyces cerevisiae

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Biomedical and Environmental Sciences 2007年第6期20卷 478-482页

作者： CAN CHEN jian-long wang Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China

Objective To investigate the characteristics of Zn^2＋ biosorption and the release of cations during the process of Zn^2＋ biosorption by intact cells of Saccharomyces cerevisiae. Methods The batch adsorption test was used to study the biosorption equilibrium and isotherm. Zn^2＋ concentration was measured with atomic adsorption spectrophotometer （AAS） AAS ***. Results When the initial concentration of Zn^2＋ ranged between 0.08 and 0.8 retool/L, the initial pH was natural （about 5.65）, the sorbent concentration was about 1 g/L and the capacity ofZn〉 biosorption was from 74.8 to 654.8 μmol/g. The pH value increased by 0.55-1.28 and the intracellular cations （K^＋, Mg^2＋, Na^＋, Ca〉） of the cells were re/eased during the process of Zn〉 biosorption. Conclusion Ion exchange was one of the mechanisms for Zn^2＋ biosorption. The biomass of Saccharomyces cerevisiae is a potential biosorbent for the removal of Zn^2＋ from aqueous solution. More work needs to be done before putting it into practical application.

关键词： Saccharomyces cerevisiae Biosorption Zinc ion Cation release

Reductive Dechlorination of p-Chlorophenol by Nanoscale Iron

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Biomedical and Environmental Sciences 2007年第5期20卷 410-413页

作者： RONG CHENG jian-long wang WEI-XIAN ZHANG Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015-3176 USA

Objective To investigate reductive dechlorination of 4-chlorophenol （4-CP） by nanoscale Fe^0 under different conditions. Methods Nanoscale Fe^0 was synthesized by using reductive method. 4-CP and its intermediate products were analyzed by HPLC. Chlorine ion was quantified with DX-100 ion chromatograph. Nano-iron particles were observed under a FEI Quanta 200 FEG environmental scanning electron microscope （ESEM）. Results The size of the particles was in the range of 10-100 nm. The nano-iron particles could reduce 4-CP effectively. The initial concentration of 4-CP increased with the decrease of the relative degradation rate, whereas the reduced amount of 4-CP increased. Temperature could influence both the dechlorination rate and the reaction pathway. Moreover, the stability and durability of nanoscale Fe^0 was evaluated through batch studies over extended periods of time. Conclusion The nanoscale Fe^0 can be used for sustainable treatment of contaminants in groundwater.

关键词： Nanoscale iron 4-CP Phenol Dechlorination Priority pollutant

Degradation of Acenaphthene by Ozone

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Biomedical and Environmental Sciences 2007年第4期20卷 291-294页

作者： DI WU YONG-JUN XU jian-long wang Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China Harbin Institute of Technology Harbin 150001 Heilongjiang China

To investigate the oxidation of acenaphthene （Ace）, a polycyclic aromatic hydrocarbon （PAH） with a saturated C-C bond by ozone and to characterize the intermediate products of ozonation. Methods Ozone was generated from filtered dry oxygen by an ozone generator and continually bubbled into a reactor containing lg/L Ace dissolved in an acetonitrile/water solvent mixture （90/10, v/v） at a rate of 0.5 mg/s. HPLC was used to analyze the Ace concentration. Total organic carbon （TOC） was used to measure the amount of water soluble organic compounds. GC-MS was used to identify the ozonized products. Oxygen uptake rate （OUR） of activated sludge was used to characterize the biodegradability of ozonized products. Results During the ozonation process, Ace was degraded, new organic compounds were produced and these intermediate products were difficult mineralize by ozone, with increasing TOC of soluble organics. The ozonized products were degraded by activated sludge more easily than Ace. Conclusion Ozonation decomposes the Ace and improves its biodegradability. The ozonation combined with biological treatment is probably an efficient and economical way to mineralize acenaphthene in wastewater.

关键词： Ozone Acenaphthene PAHs Biodegradation Persistent organic pollutant

A Novel Biosensor for the Rapid Determination of Biochemical Oxygen Demand

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Biomedical and Environmental Sciences 2007年第1期20卷 78-83页

作者： JIN-SONG CHEN LI-SHENG ZHANG jian-long wang Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China

Objective To investigate the function of a novel biosensor used for the rapid determination of biochemical oxygen demand （BOD） which is developed by our research group based on suspended immobilized microbial cell system in a completely mixed determining chamber as a substitute of the traditional membrane system. Methods Activated sludge was immobilized by PVA gel and used as a bio-sensing element. The novel biosensor was used to measure the short time BOD value and the conventional cultivation method was used for BOD5 measurement. Results A linear relationship was observed for the difference between the current and the concentration of glucose-glutamic acid （GGA） solution below 200 mg/L with a correlation coefficient of 0.995. The optimal response of the sensor was obtained at pH 7.0 and 30℃. The sensor response was within 15 min and was reproducible within ±5% of the mean in a series of eight samples containing 75 mg/L BOD using standard GGA solution. The novel sensor response was found to be fairly constant over a period of 30 days, with ±5% fluctuations. Conclusion A relatively good agreement is found between BOD estimated by the novel BOD biosensor and that determined by the conventional 5-day BOD method. This novel BOD biosensor has good sensitivity, stability and reproducibility.

关键词： BOD BOD biosensor Wastewater Water quality Water pollution

A Simple-Prepared and Multi-Reusable Adhesive Based on Epoxy Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1589-1594,I0015页

作者： Yu-Ting wang Huan Liang Yen Wei jian-long wang Xiang-Ming He Yang Yang Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China The Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing100084China

Adhesives play an important role in modern society's production and daily *** robust and sustainable adhesives remains a great *** we report a sustainable epoxy-vitrimer adhesive with high adhesive strength(about 10 MPa)and reusability(82%strength after 3 times).This adhesive can be fabricated from commercially available products through a straightforward hot-pressing method without the need of *** adhesive process is also simple,requiring only 30 min at 180℃.In addition,the vitrimer adhesive has the advantages of both erasability for reuse and excellent water *** work provides a facile strategy to fabricate high-strength adhesive that ensures reusability,recyclability,low cost of raw materials,and simple processing ***,it expands the range of potential applications for epoxy vitrimers.

关键词： Epoxy Vitrimer Adhesive Reusable Sustainable

Stationary response of colored noise excited vibro-impact system

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Chinese Physics B 2021年第6期30卷 169-175页

作者： jian-long wang Xiao-Lei Leng Xian-Bin Liu State Key Laboratory of Mechanics and Control of Mechanical Structure Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The generalized cell mapping(GCM) method is used to obtain the stationary response of a ***-impact system under a colored noise excitation. In order to show the advantage of the GCM method, the stochastic averaging method is also presented. Both of the two methods are tested through concrete examples and verified by the direct numerical simulation. It is shown that the GCM method can well predict the stationary response of this noise-perturbed system no matter whether the noise is wide-band or narrow-band, while the stochastic averaging method is valid only for the wide-band noise.

关键词： vibro-impact system stationary probability density function stochastic averaging method generalized cell mapping method

TBPA^(+·) mediated aromatization of 1,3,5-trisubstituted pyrazolines

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Chinese Chemical Letters 2008年第9期19卷 1013-1016页

作者： Gang Su Wen Tao Wu jian Tao wang long Min Wu State Key Laboratory of Applied Organic Chemistry Lanzhau University Lanzhau 730000 China

1,3,5-Trisubstituted pyrazolines were oxidized to the corresponding pyrazoles in high yield with tris（4-bromophenyl）aminium （TBPA＊＊） hexachloroantimonate in chloroform at room temperature.

关键词： Pyrazoline Aromatization Pyrazole Cation radical

Anaerobic Degradation of Tetrachloroethylene Using Different Co-substrates as Electron Donors

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Biomedical and Environmental Sciences 2006年第1期19卷 73-76页

作者： QI YANG HAI-TAO SHANG XUE-LIAN wang HUI-DI LI jian-long wang School of Water Resources and Environment China University of Geosciences Beijing 100083 China Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China

Objective To investigate the biodegradation of tetrachloroethylene （PCE） by acclimated anaerobic sludge using different co-substrates, i.e., glucose, acetate, and lactate as electron donors. Methods HP-6890 gas chromatograph （GC） in combination with auto-sampler was used to analyze the concentration of PCE and its intermediates, Results PCE could be degraded by reductive dechlorlnation and the degradation reaction conformed to the first-order kinetic equation. The rate constants are klaetate〉kglucose〉kacetate. The PCE degradation rate was the highest in the presence of lactate as an electron donor. Conclusion Lactate is the most suitable electron donor for PCE degradation and the electron donors supplied by co-metabolic substrates are not the limiting factors for PCE degradation,

关键词： Tetrachloroethylene (PCE) Co-metabolic substrate Biodegradation Electron donor