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Microbial Community Characteristics in a Degraded Wetland of the Yellow River Delta

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Pedosphere 2010年第4期20卷 466-478页

作者： WANG zhen-Yu XIN Yuan-zheng GAO dong-Mei LI Feng-Min J. MORGAN xing Bao-Shan College of Environmental Science and Engineering Ocean University of China Qingdao 266100 （China） Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 （USA）

Five different sites with a soluble salt gradient of 3.0-17.7 g kg^-1 dry soil from the coast to the inland were selected, and the microbial population size, activity and diversity in the rhizospheres of five common plant species and the adjacent bulk soils （non-rhizosphere） were compared in a degraded wetland of the Yellow River Delta, Shandong Province, China to study the effects of soil environment （salinity, seasonality, depth, and rhizosphere） on microbial communities and the wetland＇s ecological function, thus providing basic data for the bioremediation of degraded wetlands. There was a significant negative linear relationship between the salinity and the total number of microorganisms, overall microbial activity, or culturable microbial diversity. Salinity adversely affected the microbial community, and higher salinity levels resulted in smaller and less active microbial communities. Seasonal changes were observed in microbial activity but did not occur in the size and diversity. The microbial size, activity and diversity decreased with increasing soil depth. The size, activity and diversity of culturable microorganisms increased in the rhizospheres. All rhizospheres had positive effects on the microbial communities, and common seepweed had the highest rhizosphere effect. Three halophilic bacteria （Pseudomonas mendocina, Burkholderia glumae, and Acinetobacter johnsonii） were separated through BIOLOG identification, and common seepweed could be recommended for bioremediation of degraded wetlands in the Yellow River Delta.

关键词： microbial activity microbial diversity rhizosphere salinity soil microorganisms

Multiple factors influencing high-purity indium electrolytic refining

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Chinese Journal of Chemical Engineering 2024年第7期71卷 148-160页

作者： Hong-Qiang Fan Fei Li Hong-xing zheng Wu-ji Pan Mei-zhen Wu Yashar Behnamian Ju-Bo Peng dong-Hai Lin State Key Laboratory of Advanced Special Steel&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center for Integrated Circuits and Advanced Display Materials Shanghai UniversityShanghai 200444China Research&Development Center Yunnan Tin Group(Holding)Limited CompanyKunming 650032China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4AlbertaCanada School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were *** variations in impurity levels concerning gelatin concentration were *** the gelatin and In3+concentration were moderately positively correlated with the Pb *** Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl *** Bi element content was positively linked to the electrode *** the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually ***,a critical current density of 45 A·m^(-2) was identified in this behavior.

关键词： High-purity indium Electrolysis Multiple factors Electrochemistry Purification

Strain and process engineering toward continuous industrial fermentation

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1336-1353页

作者： Yufei dong Ye Zhang Dehua Liu zhen Chen Key Laboratory of Industrial Biocatalysis(Ministry of Education) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Tsinghua Innovation Center in dongguan Dongguan 523808China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China

Most current biotechnology industries are based on batch or fed-batch fermentation processes,which often show low productivity and high production costs compared to chemical *** increase the economic competitiveness of biological processes,continuous fermentation technologies are being developed that offer significant advantages in comparison with batch/fed-batch fermentation processes,including:(1)removal of potential substrates and product inhibition,(2)prolonging the microbial exponential growth phase and enhancing productivity,and(3)avoiding repeated fermentation preparation and lowering operation and installation ***,several key challenges should be addressed for the industrial application of continuous fermentation processes,including(1)contamination of the fermentation system,(2)degeneration of strains,and(3)relatively low product *** this study,we reviewed and discussed metabolic engineering and synthetic biology strategies to address these issues.

关键词： continuous fermentation productivity contamination strain degeneration metabolic engineering

Biodegradation of Crude Oil in Contaminated Soils by Free and Immobilized Microorganisms

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Pedosphere 2012年第5期22卷 717-725页

作者： WANG zhen-Yu XU Ying WANG Hao-Yun ZHAO Jian GAO dong-Mei LI Feng-Min B. xing College of Environmental Science and Engineering Ocean University of China Qingdao 266100 (China) College of Animal Science and Veterinary Medicine Qingdao Agricultural University Qingdao 266109 (China) Chemical and Mineral Metal Material Testing Center Tianjin Entry-Exit Inspection and Quarantine Bureau Tianjin 300456 (China) Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 (USA)

The efficiencies of free and immobilized bacterial cultures of petroleum hydrocarbon degraders were evaluated and compared in this study. Hydrocarbon-degrading microbial communities with high tolerance to and high degrading ability of crude oil were obtained from the soil contaminated with crude oil in the Yellow River Delta. Then, the microbial cells were immobilized in sodium alginate （SA） beads and sodium Mginate-diatomite （SAD） beads. The biodegradation of crude oil in soil by immobilized cells was compared with that by free cells at three inoculation concentrations, 1× 104 colony forming units （cfu） kg-^（-1）（low concentration, L）, 5 × 104 cfu kg^（-1）（medium concentration, M）, and 1× 105 cfu kg^（-1）（high concentration, H）. At 20 d after inoculation, the maximum degradation rate in the immobilized systems reached 29.8% （SAD-M）, significantly higher （P 〈 0.05） than that of the free cells （21.1%）, and the SAD beads showed greater degradation than the SA beads. Moreover, both microbial populations and total microbial activity reached significantly higher level （P 〈 0.05） in the immobilized systems than free cell systems at a same initial inoculation amount. The scanning electronic microscope （SEM） images also confirmed the advantages of the immobilized microstructure of SAD beads. The enhanced degradation and bacterial growth in the SAD beads indicated the high potential of SAD beads as an effective option for bioremediation of crude oil-contaminated soils in the Yellow River Delta.

关键词： bacterial growth degradation rate hydrocarbon degraders immobilized cells sodium alginate-diatomite beads

Evaluation of Auto-Ignition Characteristics of Diesel Surrogate Fuels with the Same Derived Cetane Numbers at Changed Thermodynamic Environments

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Journal of Thermal Science 2024年第4期33卷 1590-1606页

作者： ZHANG Cong GUAN Yuanhang HUANG zhen HAN dong Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China College of Smart Energy Shanghai Jiao Tong UniversityShanghai200240China Shanghai Non-carbon Energy Conversion and Utilization Institute Shanghai200240China

The ignition tendency of diesel fuels is highly sensitive to ambient conditions and fuel *** this study,the ignition characteristics of different diesel surrogate fuels with the same derived cetane numbers(DCN)were measured and compared in varied thermodynamic and oxidizing *** combustion pressures,heat release rates,ignition delays,and combustion delays of the test fuels were *** experimental results showed that the diesel surrogate fuels with the same DCNs exhibit similar ignition propensity at standard DCN test ***,for the test conditions of high cetane fuels,high ambient temperatures,and suficient oxygen concentrations,surrogate fuels with the same DCN have similar ignition behaviors,and using the DCN to evaluate fuel ignition tendency is ***,for the test conditions of low cetane fuels,low ambient temperatures,and reduced oxygen concentrations,different ignition behaviors are observed for the surrogate fuels with the same DCN,so at these conditions using DCN as the evaluation index for fuel ignition tendency may lead to higher uncertainty.

关键词： diesel fuels surrogate fuels derived cetane numbers constant volume combustion chamber

Anisotropic lattice Boltzmann-phase-field modeling of crystal growth with melt convection induced by solid-liquid density change

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Journal of Materials Science & Technology 2020年第22期54卷 26-32页

作者： Hui xing Xianglei dong dongke Sun Yongsheng Han MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Shaanxi Key Laboratory for Condensed Matter Structure and PropertiesNorthwestern Polytechnical University710129Xi'anChina College of Materials Science and Engineering Zhengzhou University450001ZhengzhouChina Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing211189China State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgyShanghai UniversityShanghaiChina The EMMS Group State Key Laboratory of Multiphase Complex Systems.Institute of Process EngineeringChinese Academy of Science100190BeijingChina

Density change is ubiquitous in phase transformation, and it can induce melt convection which strongly influences the crystal growth. Here, an anisotropic lattice Boltzmann-phase-field method was extended to predict the dendritic growth under the shrinkage or expansion melt convection by density change induced. A novel LB equation with an anisotropic coefficient was constructed to model the advancement of ordering parameter, coupling with the passive scalar LB equation for convective and diffusive heat transfer during phase transition. We studied dendritic growth and shape selection with melt convection induced by density change in crystal growth. Results show that the melt convection induced by density change affects strongly the dendritic growth. The shrinkage flow results in a higher tip velocity while the expansion flow leads to a slower one. Predicted Péclet number with respect to the relative density change was compared with an analytical solution. Moreover, the modified selection parameter has been verified by numerical simulations.

关键词： Dendritic growth Density change Melt convection Phase-field method

Synthesis of novel chiral N,P-containing multidentate ligands and their applications in asymmetric transfer hydrogenation

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Chinese Chemical Letters 2011年第11期22卷 1269-1272页

作者： Shen Luan Yu Yan Yun Li zhen Rong dong Juan Ni Zhang Qi Li Jing xing Gao State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Laboratory for Green ChemicalProductions of Alcohols-Ethers-Esters and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Novel chiral PN_4-type multidentate aminophosphine ligands have been successfully synthesized by Schiff-base condensation of bis（o-formylphenyl）phenylphosphane and various chiral *** structures were fully characterized by IR,EI-MS and *** catalytic systems,prepared in situ from the multidentate ligands and iridium（I） complexes,showed high activity in asymmetric transfer hydrogenation of propiophenone in 2-propanol solution,leading to corresponding optical alcohol with up to 75%ee.

关键词： Chiral multidentate aminophosphine ligand Iridium complex Propiophenone Asymmetric transfer hydrogenation

An experimental study on spray auto-ignition of RP-3 jet fuel and its surrogates

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Frontiers in Energy 2021年第2期15卷 396-404页

作者： Yaozong DUAN Wang LIU zhen HUANG dong HAN Key Laboratory for Power Machinery and Engineering(Ministry of Education) Shanghai Jiao Tong UniversityShanghai 200240China

Jet fuel is widely used in air transportation,and sometimes for special vehicles in ground *** the latter case,fuel spray auto-ignition behavior is an important index for engine operation *** fuel is usually used for fundamental combustion study due to the complex composition of practical *** for jet fuels,two-component or three-component surrogate is usually selected to emulate practical *** spray auto-ignition characteristics of RP-3 jet fuel and its three surrogates,the 70%mol n-decane/30%mol 1,2,4-trimethylbenzene blend(Surrogate 1),the 51%mol n-decane/49%mol 1,2,4-trimethylbenzene blend(Surrogate 2),and the 49.8%mol n-dodecane/21.6%mol iso-cetane/28.6%mol toluene blend(Surrogate 3)were studied in a heated constant volume combustion *** 1 and Surrogate 2 possess the same components,but their blending percentages are different,as the two surrogates were designed to capture the H/C ratio(Surrogate 1)and DCN(Surrogate 2)of RP-3 jet fuel,*** 3 could emulate more physiochemical properties of RP-3 jet fuel,including molecular weight,H/C ratio and *** results indicate that Surrogate 1 overestimates the auto-ignition propensity of RP-3 jet fuel,whereas Surrogates 2 and 3 show quite similar auto-ignition propensity with RP-3 jet ***,to capture the spray auto-ignition behaviors,DCN is the most important parameter to match when designing the surrogate ***,as the ambient temperature changes,the surrogates matching DCN may still show some differences from the RP-3 jet fuel,e.g.,the first-stage heat release influenced by low-temperature chemistry.

关键词： RP-3 jet fuel surrogate spray auto-ignition constant volume combustion chamber

Determination of neomycin in water samples by high performance anion chromatography with pulsed amperometric detection

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Chinese Chemical Letters 2007年第2期18卷 201-204页

作者： Bin Guan dong xing Yuan Environmental Science Research Center Xiamen University Xiamen 361005 China

A simple, fast and reliable method, using high performance anion chromatography with pulsed amperometric detection, had been developed for the analysis of neomycin in water samples. The elution and separation were carried out with an isocratic mobile phase, containing 10 mmol/L NaOH. The influence of the concentration and pH of the mobile phase on the separation and detection was investigated. A quadruple-potential waveform used for the detection was optimized. The detection limit of neomycin was down to 0.027 μg/mL. The linearity of neomycin calibration curve ranged from 0.050 to 0.505 μg/mL with correlation coefficient of 0.9997. R.S.D. (n = 11) was 4.0%.

关键词： Neomycin High performance anion chromatography Pulsed amperometric detection