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Microbial Degradation of Quinoline: Kinetics Study With Burkholderia picekttii

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Biomedical and Environmental Sciences 2004年第1期17卷 21-26页

作者： jian-longwang WEI-ZHONG XUANZHAO LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China SchoolofEnvironmentalScience PekingUniversityBeijing100871China

Objective To investigate the kinetics of quinoline biodegradation by Burkholderia pickttii, a Gram negative rod-shaped aerobe, isolated in our laboratory. Methods HPLC (Hewlett-Packard model 5050 with an UV detector) was used for the analysis of quinoline concentration. GC/MS method was used to identify the intermediate metabolites of quinoline degradation. Results The biodegradation of quinoline was inhibited by quinoline at a high concentration, and the degradation process could be described by the Haldane model. The kinetic parameters based on Haldane substrate inhibition were evaluated. The values were v = 0.44 h-1,Ks=166.7 mg/L, Ki= 650 mg/L, respectively. The quinoline concentration to avoid substrate inhibition was inferred theoretically and determined to be 329 mg/L. Conclusion The biodegradation of quinoline conforms to the Haldane inhibition model and the main intermediate metabolite of quinoline biodegradation is 2-hydroxy-quinoline.

关键词： Quinoline Microbial degradation Burkholderia pickttii Kinetics Substrate inhibition Intermediate metabolite

Biosorption of Cadmium by Fungal Biomass of Aspergillus niger

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Biomedical and Environmental Sciences 2005年第3期18卷 141-145页

作者： QIYANG jian-longwang ZHIXING LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China／／SchoolofWaterResourceandEnvironmentChinaUniversityofGeoscienceBeijing100083China LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China AnalysisCenterofTsinghuaUniversity Beijing100084China

Objective To investigate the removal of cadmium from aqueous solution by waste fungal biomass of Aspergillus niger, originated from citric acid fermentation industry. Methods Batch adsorption test was used to study the biosorption equilibrium and isotherm. The Cd2+ concentration was measured with atomic adsorption spectrophotometer (AAS) HITACHI 180-80. Results The biosorption achieved equilibrium within 30 min. The adsorption isotherm could be described by Freundlich adsorption model, and the constants KF and 1/n were determined to be 2.07 and 0.18, respectively, and the correlation efficiency was 0.97. The optimal pH for Cd adsorption was 6.0. The cadmium-laden biomass could be effectively regenerated using 0.1 N HCl. Conclusion The waste biomass of Aspergillus niger, a by-product of fermentation industry, is a potential biosorbent for the removal of cadmium from aqueous solution.

关键词： Cadmium Heavy metal pollution Aspergillus niger Biomass Biosorption

Microbial Degradation of Aniline by Bacterial Consortium

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Biomedical and Environmental Sciences 2003年第4期16卷 398-404页

作者： jian-longwang ZE-YUMAO WEI-ZHONG LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeifing100084China DepartmentofHydraulicEngineering TsinghuaUniversityBeijing100084China SchoolofEnvironmentalScience PekingUniversityBeijing100871China

Objective To investigate the characteristics of microbial degradation of aniline by a stable bacterial consortium. Methods The bacterial consortium was isolated from activated sludge treating chemical wastewater using aniline as the sole source of carbon and nitrogen by enrichment and isolation technique. The biomass was measured as optical density (OD) at 510 run using a spectrophotometer. Aniline concentrations were determined by spectrophotometer. The intermediates of aniline degradation were identified by GC/MS method. Results The bacterial consortium could grow at a range of aniline concentrations between 50 and 500 mg/L. The optimal pH and temperature for aniline degradation were determined to be 7.0 and 30, respectively. The presence of NH4NO3 as an additional nitrogen source (100-500 mg/L) had no adverse effect on bacterial growth and aniline degradation. The presence of heavy metal ions, such as Co2+, Zn2+, Ni2+, Mn2+ and Cu2+ had an inhibitory effect on aniline degradation. Conclusions The isolated bacterial consortium can degrade aniline up to 500 mg/L effectively and tolerate some heavy metal ions that commonly exist in chemical wastewater. It has a potential to be applied in the practical treatment of aniline-containing wastewater.

关键词： Aniline Priority pollutant Biodegradation Wastewater treatment

Slurry-phase Biological Treatment of Nitrophenol Using Bioaugmentation Technique

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Biomedical and Environmental Sciences 2005年第2期18卷 77-81页

作者： jian-longwang GANGZHAO LI-BOWU LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China／／CollegeofEnvironmentalScienceandEngineeringNankaiUniversityTianjin300071China LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China CollegeofEnvironmentalScienceandEngineering NankaiUniversityJianjin300071China

Objective To investigate the performance of soil-slurry bioreactor used for remediating contaminated soil with 4-nitrophenol (4-NP). Methods The slurry bioreactor was used to degrade different concentrations of 4-nitrophenol with or without inoculating the acclimated activated sludge. HPLC system (Hewlett-Packard model 5050 with a UV detector) was used for the quantification of 4-nitrophenol. Results The indigenous microorganisms exhibited a little activity for simulated soil with 50 mg 4-NP/kg soil. However, at the concentration of 10 mg 4-NPkg soil, a considerable degradation occurred within two weeks. It appeared that high concentrations of 4-nitrophenol apparently produced an inhibitory effect on microbial activity. For system receiving 50 mg 4-NP/kg soil, the maximum rate of 4-NP degradation measured in the reactor inoculated with 25 g sludge/kg soil was approximately 10 times higher than the uninoculated reactor, suggesting that the degradation rate of 4-nitrophenol could be enhanced greatly by means of inoculating acclimated sludge. Conclusion The addition of sludge capable of degrading 4-nitrophenol can result in enhance the degradation rate of 4-nitrophenol.

关键词： Biodegradation Bioremediation Slurry bioreactor 4-nitrophenol Soil

Bioremediation of Quinoline-contaminated Soil Using Bioaugmentation in Slurry-phase Reactor

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Biomedical and Environmental Sciences 2004年第2期17卷 187-195页

作者： jian-longwang ZE-YuMAO LI-PINGHAN ANDYIQIAN LaboratoryofEnvironmentalTechnology InetTsinghuaUniversityBeijing100084China DepartmentofHydraulicEngineering TsinghuaUniversityBeijing100084China StateKeyJointLaboratoryofEnvironmentSimulationandPollutionControl TsinghuaUniversityBeijing100084China

Objective To investigate the possibility of using bioaugmentation as a strategy for remediating quinoline-contaminated soil. Methods Microorganisms were introduced to the soil to assess the feasibility of enhancing the removal of quinoline from quinoline-contaminated soil. Slurry-phase reactor was used to investigate the bioremediation of quinoline-contaminated soil. HPLC (Hewlett-Packard model 5050 with an UV detector) was used for analysis of quinoline concentration. Results The biodegradation rate of quinoline was increased through the introduction of Burkholderia pickettii. Quinoline, at a concentration of 1 mg/g soil, could be removed completely within 6 and 8 hours with and without combined effect of indigenous microbes, respectively. Although the indigenous microbes alone had no quinoline-degrading ability, they cooperated with the introduced quinoline-degrader to remove quinoline more quickly than the introduced microbes alone. Bioaugmentaion process was accelerated by the increase of inoculum size and bio-stimulation. The ratio of water to soil in slurry had no significant impact on bioremediation results. Conclusion Bioaugmetation is an effective way for bioremediation of quinoline-contaminated soil.

关键词： Bioaugmentation Biodegradation Quinoline Persistent organic pollutants Slurry-phase bioreactor

Effect of Salinity Variations on the Performance of Activated Sludge System

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Biomedical and Environmental Sciences 2005年第1期18卷 5-8页

作者： jian-longwang XIN-MINZHAN YE-CHENGFENG YIQIAN LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China StateKeyJointLaboratoryofEnvironmentSimulationandPollutionControl TsinghuaUniversityBeijing100084China

To investigate the influence of salinity variations on the performance of activated sludge systems, treating domestic wastewater. Methods The completely mixed reactor was used and operated in a batch-wise mode. The activated sludge taken from the Gaobeidian Wastewater Treatment Plant was used as a seeding sludge. Total organic carbon (TOC), oxygen uptake rate (OUR) and suspended solids (SS) were used as parameters to characterize the performance of the treatment systems. TOC was measured using a TOC-analyzer (TOC-5000, Japan). The OUR value was measured with a dissolved oxygen meter (YSI model-58). SS was measured gravimetrically. Results The TOC removal efficiency and the OUR value of activated sludge were not deteriorated when the NaCl shock concentration was less than 0.5 g/L. However, when the NaCl shock concentrations were up to 10g/L and 20 g/L, the OUR of activated sludge was reduced by 35% and TOC removal efficiency was dropped by 30%, compared with the control experiment without NaCl shock loading. Conclusion The effect of NaCl shock loading on the activated sludge wastewater treatment system is dependant upon the NaCl concentrations and the degree of influence can be inferred through the change of substrate utilization rate at different shock NaCl loadings.

关键词： Activated sludge Saline wastewater NaCl Shock loading TOC OUR

Emergent Geometry of KP Hierarchy

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Acta Mathematica Sinica,English Series 2024年第1期40卷 3-25页

作者： jian ZHOU Department of Mathematical Sciences Tsinghua UniversityBeijng 100084P.R.China

We explain how to construct a quantum deformation of a spectral curve associated to a tau-function of the KP *** construction is applied to Witten-Kontsevich tau-function to give a natural explanation of some earlier ... 详细信息

关键词： KP hierarchy tau-functions spectral curves

Development in oxide metallurgy for improving the weldability of high -strength low-alloy steel-Combined deoxidizers and microalloying elements

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1263-1284页

作者： Tingting Li jian Yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles during *** chaotically oriented IAF and refined PAGs inhibit crack initiation and propagation in the steel,resulting in high impact *** work summarizes the com-bined effect of deoxidizers and alloying elements,with the aim to provide a new perspective for the research and practice related to im-proving the impact toughness of the heat affected zone(HAZ)during the high heat input *** complex deoxidation with other strong deoxidants,such as Mg,Ca,Zr,and rare earth metals(REMs),can improve the toughness of the heat-affected zone(HAZ)by re-fining PAGs or increasing IAF ***,it is difficult to identify the specific phase responsible for IAF nucleation because ef-fective inclusions formed by complex deoxidation are usually *** alloying elements,such as C,Si,Al,Nb,or Cr,con-tents can impair HAZ toughness.A high C content typically increases the number of coarse carbides and decreases the potency of IAF ***,Cr,or Al addition leads to the formation of undesirable *** reduces the high-temperature stability of the ***,V,and B can enhance HAZ ***-containing precipitates present good thermal *** or V(C,N)is ef-fective in promoting IAF nucleation due to its good coherent crystallographic relationship with *** formation of the B-depleted zone around the inclusion promotes IAF *** interactions between alloying elements are complex,and the effect of adding dif-ferent alloying elements remains to be *** the future,the interactions between various alloying elements and their effects on ox-ide metallurgy,as well as the calculation of the nucleation effects of effective inclusions using first principles calculations will become the focus of

关键词： oxide metallurgy technology heat affected zone high-strength low-alloy steel intragranular acicular ferrite microalloying element

Editorial of special issue on the 20th anniversary of Wuhan National Laboratory for Optoelectronics(WNLO)

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Chinese Optics Letters 2024年第2期22卷 1-2页

作者： jian Wang WNLO Huazhong University of Science and Technology

On the occasion of the 20th anniversary of the founding of Chinese Optics Letters,Wuhan National Laboratory for Optoelectronics(WNLO)has also gone through 20 *** is one of six national research centers approved by the Ministry of Science and Technology of China in *** predecessor was Wuhan National Laboratory for Optoelectronics(preparatory),one of five national laboratories approved for preparatory construction by the Ministry of Science and Technology of China in November *** was jointly built by the Ministry of Science and Technology of China,Ministry of Education of China,Hubei Provincial Government,and Wuhan Municipal Government.

关键词： jointly anniversary Wuhan