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

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

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Locating the Source Regions of the Single and Double-Frequency Microseisms to Investigate the Source Effects on HVSR in Site Effect Analysis

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Journal of Earth Science 2022年第5期33卷 1219-1232页

作者： zhen Guo mei Xue Adnan Aydin Yu Huang State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China College of Civil Engineering Tongji UniversityShanghai200092China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai200092China Shanghai Sheshan National Geophysical Observatory Shanghai201602China Department of Geology and Geological Engineering University of MississippiOxfordMS38677USA

Evaluating the seismic site effect by the ambient noise based horizontal-to-vertical spectral ratio(HVSR)method is strongly affected by the spatial and temporal variations of the ambient noise ***,it is necessary to locate the source regions of ambient noise and investigate the relationships between the source energy and HVSR values at the predominant frequency(HVSRf_(0))of the *** generation mechanisms of the single-and double-frequency microseisms(SFMs,0.05-0.085 Hz and DFMs,0.1-0.5 Hz)in ambient noise are better understood than the noise in other frequency bands and they are dominantly composed of fundamental Rayleigh(Rg)*** this advantage,the recordings of SFMs and DFMs at 30 stations in the east coast region of the United States are used to demonstrate a study on locating their source regions with reasonable certainty and constructing the functional relationship between the HVSRf_(0) and the source energy of SFMs and *** recordings are processed in four sub-frequency bands(Fs)of SF and DF bands and a polarization analysis is carried out to select the ellipsoids approximating the particle motions of Rg *** the probability density functions of the back azimuths of the ellipsoids’semi-major axes are computed for each F and station,and are projected on the ocean to determine their possible source *** regions are further constrained by(1)the correlation coefficients between the SFMs and the WAVEWATCHⅢ(WWⅢ)hindcasts of ocean wave spectra in the SF band,or between the DFMs and the modeled DF energy on ocean surface in the selected time windows in the DF band,(2)the energy contribution defined by(i)the average WWⅢocean wave energy and the ocean bottom topographical gradient in the SF band,or(ii)the average modeled DF energy on ocean surface and a frequency and water depth dependent coefficient measuring the conversion efficiency of DF energy from water to solid earth in the DF band,and(3)the percentile retained energy of

关键词： seismic site effect HVSR single-frequency microseisms double-frequency microseisms polarization analysis geophysics

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DESIGN OF 6-AXIS FORCE/TORQUE SENSOR BASED ON STEWART PLATFORM RELATED TO ISOTROPY

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Chinese Journal of Mechanical Engineering 1998年第3期11卷 54-59页

作者： Wang, Hongrui gao, Feng Huang, zhen Yanshan Univ China

A model of the solution space for all the sensor mechanisms based on the Stewart platform is established, which is a novel and useful tool for investigation of the optimal sensor design. A kind of performance evaluation atlases are plotted within the model of the solution space, which clearly show relationships between the condition number of Jacobjan matrix and parameters of all the sensor mechanisms. By using the performance atlases, an optimal design for the sensor mechanism can be achieved. Because the elastic joints are proposed for replacing the spherical joints, the Stewart platform based sensor can be designed as small as possible.

关键词： Steward platform Sensor Isotropy

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Current and future editing reagent delivery systems for plant genome editing

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Science China(Life Sciences) 2017年第5期60卷 490-505页

作者： Yidong Ran zhen Liang Caixia gao Genovo Biotechnology Co. Ltd. Tianjin 301700 China State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Many genome editing tools have been developed and new ones are anticipated; some have been extensively applied in plant genetics, biotechnology and breeding, especially the CRISPR/Cas9 system. These technologies have opened up a new era for crop improvement due to their precise editing of user-specified sequences related to agronomic traits. In this review, we will focus on an update of recent developments in the methodologies of editing reagent delivery, and consider the pros and cons of current delivery systems. Finally, we will reflect on possible future directions.

关键词： genome editing DNA RNA RNP and virus delivery Agrobacterium-mediated transformation biolistic method protoplast transfeetion ttransgene-free genome edited plant

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Highly oxidized graphene with enhanced fluorescence and its direct fluorescence visualization

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Science China Chemistry 2014年第4期57卷 605-614页

作者： WENG ZhuLin XU zhen gao Chao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University School of Mathematical and Physical Sciences Hubei University for Nationalities

We prepared hyper-oxidized graphene(HOG) as a form of graphene derivative by additional oxidation of graphene oxide(GO) sheets. HOG, which formed more functional groups and isolated conjugated clusters on the sheets, accordingly showed high solubility in water and alcohols, high transmittance and film transparence, longer fluorescence decay constant time, and enhanced fluorescence in states of solution and solid. By contrast, GO has much weaker fluorescence in solution and its fluorescence is totally quenched in solid. The influences of concentration, metallic ions, and pH on HOG fluorescence in aqueous solution were also investigated in detail. Due to HOG's strong fluorescence, direct visualization was realized on substrates and in solution. In addition, direct 3D fluorescence visualizations of HOG phase in polymer composites were achieved. These results show the great potential of HOG in a broad range of applications, from biological labeling, probes, and drug carriers to highperformance composites and nanomanipulation.

关键词： highly oxidized graphene enhanced fluorescence fluorescent visualization

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Zircon U-Pb Geochronology and Geochemistry of the Early Cretaceous Volcanic Rocks from the Manitu Formation in the Hongol Area, Northeastern Inner Mongolia

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1286-1304页

作者： ZHANG Xiangxin SU zhen gao Yongfeng College of Resource Science Hebei GEO University Shijiazhuang 050031 Hebei China

We undertook zircon U-Pb dating and geochemical analyses of volcanic rocks from the Manitu Formation in the Hongol area, northeastern Inner Mongolia, to determine their age, petrogenesis and sources, which are important for understanding the Late Mesozoic tectonic evolution of the Great Xing＇an Range. The volcanic rocks of the Manitu Formation from the Hongol area consist primarily of trachyandesite, based on their chemical compositions. The zircons from two of these trachyandesites are euhedral-subhedral in shape, display clear oscillatory growth zoning and have high Th/U ratios （0.31- 1.15）, indicating a magmatic origin. The results of LA-ICP-MS zircon U-Pb dating indicate that the volcanic rocks from the Manitu Formation in the Hongol area formed during the early Early Cretaceous with ages of 138.9-140.5 Ma. The volcanic rocks are high in alkali （Na2O ＋ K2O = 6.22-8.26 wt%）, potassium （K2O = 2.49-4.58 wt%） and aluminium （Al2O3 = 14.27-15.88 wt%）, whereas they are low in iron （total Fe2O3 = 3.76-6.53 wt%） and titanium （TiO2 = 1.02-1.61 wt%）. These volcanic rocks are obviously enriched in large ion lithophile elements, such as Rb, Ba, Th and U, and light rare earth elements, and are depleted in high field strength elements, such as Nb, Ta and Ti with pronounced negative anomalies. Their Sr-Nd-Pb isotopic compositions show positive εNd（t）（＋0.16%o t0＋1.64%o） and low TDM（t）（694--767 Ma）. The geochemical characteristics of these volcanic rocks suggest that they belong to a shoshonitic series and were likely generated from the partial melting of an enriched lithospheric mantle that was metasomatised by fluids released from a subducted slab during the closure of the Mongol- Okhotsk Ocean. Elemental and isotopic features reveal that fractional crystallization with the removal of ferromagnesian minerals, plagioclase, ilmenite, magnetite and apatite played an important role during the evolution of the magma. These shoshonitic rocks were produced by the partial melting of

关键词： shoshonitic rocks Manitu Formation geochronology geochemistry northeastern Inner Mongolia

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Graphene fiber based supercapacitors:Strategies and perspective toward high performances

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Journal of Energy Chemistry 2018年第1期27卷 6-11页

作者： Qiuyan Yang zhen Xu Chao gao MOE Key Laboratory of Macromolecular Synthesis and Functionalization.Department of Polymer Science and Engineering Key Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang Province.Zhejiang UniversityHangzhou 310027Zhejiang.China

Modern wearable electronics are thirsty for flexible, lightweight energy storage and supply devices. Flexible fiber-shaped supercapacitors, possess good flexibility, high power density, fast charging capability and long cycle life, becoming a promising option for wearable devices. The past decade has witnessed the emergence of graphene fiber based supercapacitors（GFSCs） as one of the most active vicinity in fiber-supercapactiors, for their excellent properties including high surface area, chemical stability, excellent electrical conductivity, lightweight and mechanical properties. In this perspective, we introduced the basic energy storage mechanisms of GFSCs, followed by the analysis in improving their overall performances, recent advances, and a conclusive discussion on the challenges and opportunities.

关键词： Graphene Fiber Two-dimensional materials Supercapacitors Energy storage

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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

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Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1143-1160页

作者： Jing ZHAO Chun mei GAN zhen Hai LIU School of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China Guangxi Colleges and Universities Key Laboratory of Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach ***,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational ***,some topological properties of the solution set are established such as boundedness,closedness and ***,we explore the upper semicontinuity of the solution ***,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

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Structure–activity relationship and mechanisms of reagents used in scheelite flotation

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Rare Metals 2015年第12期34卷 882-887页

作者： Wan-Zhong Yin Ji-zhen Wang Zhong-mei Sun School of Resource and Civil Engineering Northeastern University Design & Research Institute of Zijin

Effects of carboxylic acid collector, benzohydroxamic acid (BHA), sodium hexametaphosphate (SHAP), sodium silicate, and oxalic acid on scheelite flotation were studied through flotation tests, quantum chemical calculation, and flotation solution computational chemistry. In terms of the calculation results, the relationship between chemical reactions occurring on the scheelite surface and molecular structures of the reagents were analyzed. The results show that BHA and carboxylic acid collectors interact with scheelite in different forms and the recovery of scheelite using sodium oleate as collector declines successively from SHAP, sodium silicate, to oxalic acid. Moreover, it is found that the performance of depressant in scheelite flotation is directly related to the group electronegativity, indicating that the latter is a dominant factor that determines the former. These findings will be helpful to the academic research communities of scheelite flotation.

关键词： Scheelite Flotation Flotation reagents Structure–activity relationship

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