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Drift Mode Growth Rate and Associated Ion Thermal Transport in Reversed Magnetic Shear Tokamak Plasma

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chinese Physics Letters 2001年第5期18卷 650-652页

作者： WANG ai-Ke QIU Xiao-Ming Southwestern Institute of Physics P.O.Box 432Chengdu 610041

Drift mode linear growth rate and quasi-linear ion thermal transport in the reversed magnetic shear plasma are investigated by using the two-fluid theory,previously developed by Weiland and the chalmers group[***,29(1989)1810;ibid.30(1990)983].The theory is here extended to including both the radial electrical field shear(d E_(r)/dr)and the electron fluid velocity(V_(e))in the sheared coordinate ***,Ve describes the coupling between the safety factor q and the E_(r) × B velocity *** influences on the growth rate and associated ion thermal transport are obtained numerically,In addition,the ion heat pinch in the reversed shear plasma is ***,the present conclusions are in good agreement with the experimental results.

关键词： reversed Shear theory

Pinches-Induced Transport Reduction in Reversed Shear/Optimized Shear Tokamak Plasmas

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chinese Physics Letters 1999年第9期16卷 662-664页

作者： QIU Xiao-ming WANG ai-ke Southwestern Institute of Physics (P.O.Box 432)Chengdu 610041

The analytical formulas for anomalous particle and ion thermal diffusivities,Dte and xti,are derived on the basis of the two-fluid equations of our previous paper[***.15(1998)721].The two formulas involve five factors:(reversed/optimized)magnetic shear LB(r),E x B sheared velocity VE(r),where E is from the gradient of the ion pressure Pi,and the three ways of coupling between them,L-1B(dVE/dr),L-1B VE,and ***,where k is the LB-dependent *** is found that the five factors can produce turbulent particle-and heat-pinch,i.e.,Dtecore region of tokamaks,and hence the effective particle and ion thermal diffusivities,Deeff and xieff,reduce significantly in that *** numerical results for Deeff and xieff are in good agreement with experimental values.

关键词： Shear particle reversed

corrosion resistance of composite coating on magnesium alloy using combined microarc oxidation and inorganic sealing

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中国有色金属学会会刊：英文版 2012年第S3期22卷 760-763页

作者： YANG Wei WANG ai-ying JIANG Bai-ling Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences School of Material Science and Engineering Xi'an University of Technology

The combined microarc oxidation (MAO) and inorganic sealing process was used to deposit a composite coating to improve the corrosion resistance of AZ31 magnesium *** surface morphologies of the resulting duplex coatings were studied by ***,the corrosion resistance of the coated Mg alloy substrates was investigated using electrochemical workstation and dropping corrosion *** results show that the composite coating surface consists of Mg,Si,O and *** is difficult to deposit inorganic coating on a thick MAO coating *** the composite coating was solidified by cO2 under 175 °c,it exhibits a better corrosion resistance than the MAO monolayer,owing to the thick and compact inorganic coating.

关键词： AZ31 magnesium alloy microarc oxidation composite coating microstructure corrosion resistance

Responses of leaf water potential and gas exchange to the precipitation manipulation in two shrubs on the chinese Loess Plateau

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Journal of Arid Land 2020年第2期12卷 267-282页

作者： LI Yangyang cHEN Jiacun ai Shaoshui SHI Hui State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China Institute of Soil and Water conservation Chinese Academy of SciencesYangling 712100China School of Environmental and Municipal Engineering Xi'an University of Arc

Regulation of leaf gas exchange plays an important role in the survival of trees and shrubs under future climate change. However, the responses of leaf water potential and gas exchange of shrubs in semi-arid areas to the precipitation alteration are not clear. Here, we conducted a manipulated experiment with three levels of precipitation, i.e., a control with ambient precipitation, 50% above ambient precipitation(irrigation treatment), and 50% below ambient precipitation(drought treatment), with two common shrubs, Salix psammophila c. Wang & c. Y. Yang(isohydric plant, maintaining a constant leaf water potential by stomatal regulation) and caragana korshinskii Kom.(anisohydric plant, having more variable leaf water potential), on the chinese Loess Plateau in 2014 and 2015. We measured the seasonal variations of predawn and midday leaf water potential(Ψpd and Ψmd), two parameters of gas exchange, i.e., light-saturated assimilation(An) and stomatal conductance(gs), and other foliar and canopy traits. The isohydric S. psammophila had a similar An and a higher gs than the anisohydric c. korshinskii under drought treatment in 2015, inconsistent with the view that photosynthetic capacity of anisohydric plants is higher than isohydric plants under severe drought. The two shrubs differently responded to precipitation manipulation. Ψpd, An and gs were higher under irrigation treatment than control for S. psammophila, and these three variables and Ψmd were significantly higher under irrigation treatment and lower under drought treatment than control for c. korshinskii. Leaf water potential and gas exchange responded to manipulated precipitation more strongly for c. korshinskii than for S. psammophila. However, precipitation manipulation did not alter the sensitivity of leaf gas exchange to vapor-pressure deficit and soil moisture in these two shrubs. Acclimation to long-term changes in soil moisture in these two shrubs was primarily attributed to the changes in leaf or canopy

关键词： drought irrigation leaf water potential gas exchange acclimation

Hierarchically porous polymers with ultra-high affinity for bisphenol A enables high efficient water purification

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Science china chemistry 2021年第8期64卷 1389-1400页

作者： Zelun Li Juan Wang Qian chen Kelong ai Lehui Lu State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China Department of Pharmacology Xiangya School of Pharmaceutical SciencesCentral South UniversityChangsha410078China

The widespread use of bisphenol A(BPA)poses a serious threat to the environment and human ***,efficient removal of BPA in water is incredibly challenging,owing to the inert chemical nature and electrical neutrality of *** order to solve this problem,for the first time,we propose that a strategy of designing conjugated porous polymers with the pore size matching the size of BPA can greatly enhance the binding force of *** this basis,we developed a novel conjugated poly 1,3,5-tri[4-(diphenylamino)phenyl]benzene(MPDPB)with intrinsic pore matching the size of BPA and multi-stage porous structure by editing polymerization with *** binding energy of MPDPB to BPA is the highest at present(37.84 kcal/mol),which is 2.3 times that of the most powerful adsorbent previously reported and five times that of the conventional *** advantages make MPDPB have super-high adsorption performance towards BPA and high absorbing stability under extreme ***,MPDPB could be easily loaded on a non-woven fabric to generate point-of-use devices,which could eliminate more than 99.8%of BPA,making it the best BPA candidate adsorbent *** believe that the proposed material design derived from the specific structure of the contaminant molecule can be extended to exploring further innovative adsorbents.

关键词： bisphenol A porous polymer water purification adsorbent micropollutant

Theoretical Study on Two c_(16)H_(12)O_4 Isomers of Derivatives of Pagodane

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chinese Journal of Structural chemistry 2006年第2期25卷 180-186页

作者： LIU Feng-Ling DU ai-Ming WANG Su-Jing Department of chemistry Shandong Normal University Jinan 250014 China

Two c16H12O4 isomers of derivatives of pagodane were firstly reported and studied by using DFT method. Geometries, energies, and vibrational frequencies have been calculated for the two c16H12O4 isomers with pagodane-like structures at the B3LYP/6-31G^＊＊ level of theory. Symmetries of isomer 1 and 2 are D2h and D2d, respectively. Heats of formation for the two c16H12O4 isomers have been estimated in this paper. According to the heats of formation, the two c16H12O4 isomers are more stable than pagodane. Heats of formation as well as the vibrational analysis indicate that the two c16H12O4 isomers enjoy sufficient stability to allow for the experimental preparation.

关键词： two c16H12O4 isomers of derivatives of pagodane B3LYP/6-31G^**,vibrational frequency heat of formation

c–F bond activation under transition-metal-free conditions

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Science china chemistry 2021年第10期64卷 1630-1659页

作者： Han-Jun ai Xingxing Ma Qiuling Song Xiao-Feng Wu Leibniz-Institut fur Katalyse e.V.an der Universitat Rostock Rostock 18059Germany Dalian National Laboratory for clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Key Laboratory of Molecule Synthesis and Function Discovery Fujian Province UniversityCollege of ChemistryFuzhou UniversityFuzhou 350108China Institute of Next Generation Matter Transformation College of Material Sciences&EngineeringHuaqiao UniversityXiamen 361021China

The unique properties of fluorine-containing organic compounds make fluorine substitution attractive for the development of pharmaceuticals and various specialty materials,which have inspired the evolution of diverse c–F bond activation *** many advances have been made in functionalizations of activated c–F bonds utilizing transition metal complexes,there are fewer approaches available for nonactivated c–F bonds due to the difficulty in oxidative addition of transition metals to the inert c–F *** this regard,using Lewis acid to abstract the fluoride and light/radical initiator to generate the radical intermediate have emerged as powerful tools for activating those inert c–F ***,these transition-metal-free processes are greener,economical,and for the pharmaceutical industry,without heavy metal *** review provides an overview of recent c–F bond activations and functionalizations under transition-metal-free *** key mechanisms involved are demonstrated and discussed in ***,a brief discussion on the existing limitations of this field and our perspective are presented.

关键词： transition-metal-free fluorinated compounds c–F activation coupling

Feasible strategy for the nitrogen fixation and humification quality improvement by spent mushroom substrate as conditioning agent

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 235-240页

作者： Shuang ai Yuanbei Zhang Guoxiang Zheng college of Engineering Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Swine Facilities Engineering Ministry of Agriculture and Rural AffairsHarbin 50030China Heilongjiang Key Laboratory of Technology and Equipment for the Utilization of Agricultural Renewable Resources Harbin 150030China

There is an overlooked problem which increasing microbial abundance while reducing nitrogen loss during *** study investigated the viability of spent mushroom substrate(SMS)as conditioners in the aerobic composting of kitchen waste(KW)with cattle manure(cM).The variation of temperature,pH,c/N,organic matter,cellulose,hemicelluloses,germination index(GI),and microflora structure were explored to evaluate the potential in accelerating maturity and nitrogen fixation by SMS *** results showed that the addition of SMS accelerated the heating rate,prolonged the high temperature time,and decreased organic matter,hemicellulose,and cellulose by 17.49%,23.61%,and 18.62%,*** GI reached 105.86%with SMS addition,while 74.17%was found in control treatment after *** changed the microbial community composition and increased the species ***,clostridium XI and Azomonas were dominant bacteria,which increased the retention of nitrogen,promoted organic matter degradation and reduce compost *** study can provide a feasible strategy for nitrogen fixation in the field of organic waste recycling.

关键词： spent mushroom substrate conditioning agent nitrogen fixation humification quality aerobic composting

Viscosity, heat conductivity, and Prandtl number effects in the Rayleigh-Taylor Instability

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Frontiers of physics 2016年第6期11卷 183-196页

作者： Feng chen ai-Guo Xu Guang-cai Zhang School of Aeronautics Shah Dong Jiaotong University Jinan 250357 China National Key Laboratory of computational Physics Institute of Applied Physics and Computational Mathematics P.O. Box 8009-26 Beijing 100088 China center for Applied Physics and Technology MOE Key center for High Energy Density Physics Simulations College of Engineering Peking University Beijing 100871 China

The two-dimensional Rayleigh-Taylor instability problem is simulated with a multiple-relaxation-time discrete Boltzmann model with a gravity term. Viscosity, heat conductivity, and Prandtl number effects are probed from macroscopic and nonequilibrium viewpoints. In the macro sense, both viscosity and heat conduction show a significant inhibitory effect in the reacceleration stage, which is mainly achieved by inhibiting the development of the Kelvin-Helmholtz instability. Before this, the Prandtl number effect is not sensitive. Viscosity, heat conductivity, and Prandtl number effects on nonequilibrium manifestations and the degree of correlation between the nonuniformity and the nonequilibrium strength in the complex flow are systematically investigated.

关键词： discrete Boltzmann model/method multiple-relaxation-time Rayleigh-Taylor instability nonequilibrium