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Journal of Environmental Sciences 2022年第5期34卷 103-113页

作者： Junwen Chen Huacong Liu Yaohui Bai jing qi Weixiao qi Huijuan Liu Jianfeng Peng Jiuhui Qu Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Lake mixing influences aquatic chemical properties and microbial community composition,and thus,we hypothesized that it would alter microbial community assembly and *** clarify this issue,we explored the community assembly processes and cooccurrence networks in four seasons at two depths(epilimnion and hypolimnion)in a mesotrophic and stratified lake(Chenghai Lake),which formed stratification in the summer and turnover in the *** the stratification period,the epilimnion and hypolimnion went through contrary assembly processes but converged to similar assembly patterns in the mixing *** a highly homogeneous selection environment,species with low niche breadth were filtered,resulting in decreased species *** mixing in the winter homogenized the environment,resulting in a simpler microbial cooccurrence ***,we observed a high abundance of the cyanobacterial genus Planktothrix in the winter,proba-bly due to nutrient redistribution and Planktothrix adaptivity to the winter environment in which mixing played important *** study provides deeper fundamental insights into how environmental factors influence microbial community structure through community assembly processes.

关键词： Stratified lake Water mixing Microbial community assembly Microbial interaction Planktothrix

Boundary Lipschitz Regularity of Solutions for Semilinear Elliptic Equations in Divergence Form

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Acta Mathematica Sinica,English Series 2023年第2期39卷 193-208页

作者： jing qi LIANG Li He WANG Chun qin ZHOU School of Mathematical Sciences CMA-ShanghaiShanghai Jiao Tong UniversityShanghai200240China Department of Mathematics University of IowaIowa CityIAUSA

In this paper,we consider the pointwise boundary Lipschitz regularity of solutions for the semilinear elliptic equations in divergence form mainly under some weaker assumptions on nonhomogeneous term and the *** the domain satisfies C1,Dinicondition at a boundary point,and the nonhomogeneous term satisfies Dini continuity condition and Lipschitz Newtonian potential condition,then the solution is Lipschitz continuous at this ***,we generalize this result to Reifenberg C1,Dinidomains.

关键词： Boundary Lipschitz regularity semilinear elliptic equation Dini condition Reifenberg domain

Degradation of Organic Pollutants in Water by Catalytic Ozonation

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Chemical Research in Chinese Universities 2007年第3期23卷 273-275页

作者： LI Xin YAO Jun-hai qi jing-yao Department of Applied Chemistry School of Civil Engineer Harbin Institute of Technology Harbin 150090 P. R. China

Different series of transition metal catalysts supported on Al2O3 were prepared by the impregnation method. The catalytic activity was measured in a batch reactor with ozone as the oxidizing reagent. The experimental results indicate that Cu/Al2O3 has a very effective catalytic activity during the ozonation of organic pollutants in water. The optimum conditions for preparing Cu/Al2O3 were systematically investigated with the orthogonal testing method. Furthermore, the results also show that the surface properties of catalyst are not compulsory for effective oxidation.

关键词： Catalytic ozonation Catalyst Orthogonal experiment Water treatment

Chemical Degradation of Amine-cured DGEBA Epoxy Resin in Supercritical 1-Propanol for Recycling Carbon Fiber from Composites

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Chinese Journal of Polymer Science 2014年第11期32卷 1550-1563页

作者： Hua Yan 吕春祥 De-qi jing Xiang-lin Hou National Engineering Laboratory for Carbon Fiber Technology Institute of Coal ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of Sciences

Chemical degradation of diglycidyl ether of bisphenol A（DGEBA） epoxy resin cured with an aliphatic amine in supercritical 1-propanol was investigated under different reaction temperature and time. The combination of GC-MS and LC-MS proved that the epoxy resin was decomposed to five main products including phenol, 4-isopropylphenol, 4-isopropenylphenol, bisphenol A, and 4,4’-（cyclopropane-1,1-diyl）diphenol. The 13C-NMR results verified the chemical structures of the degradation products. The change of the products′ yield with time was evaluated by an effective means of HPLC. In addition, the GPC analysis confirmed the formation of soluble low molecular weight clusters during the degradation reaction. A possible free-radical reaction mechanism was proposed for chemical depolymerization of the epoxy resin in supercritical 1-propanol. After the homolytic cleavage of the aromatic ether linkages, the resulting bisphenol A biradical either produced 4,4’-（cyclopropane-1,1-diyl）diphenol after intramolecular rearrangement or generated bisphenol A after capturing hydrogen from 1-propanol.

关键词： Epoxy Thermosets Degradation Recycling.

Selection of water source for water transfer based on algal growth potential to prevent algal blooms

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Journal of Environmental Sciences 2021年第5期33卷 246-254页

作者： Yongjun Song jing qi Le Deng Yaohui Bai Huijuan Liu Jiuhui Qu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China University of Chinese Academy of Sciences Beijing 100049China

Water transfer is becoming a popular method for solving the problems of water quality deterioration and water level drawdown in lakes. However, the principle of choosing water sources for water transfer projects has mainly been based on the effects on water quality, which neglects the influence in the variation of phytoplankton community and the risk of algal blooms. In this study, algal growth potential(AGP) test was applied to predict changes in the phytoplankton community caused by water transfer projects. The feasibility of proposed water transfer sources(Baqing River and Jinsha River) was assessed through the changes in both water quality and phytoplankton community in Chenghai Lake, Southwest China. The results showed that the concentration of total nitrogen(TN) and total phosphorus(TP) in Chenghai Lake could be decreased to 0.52 mg/L and 0.02 mg/L respectively with the simulated water transfer source of Jinsha River. The algal cell density could be reduced by 60%, and the phytoplankton community would become relatively stable with the Jinsha River water transfer project, and the dominant species of Anabaena cylindrica evolved into Anabaenopsis arnoldii due to the species competition. However, the risk of algal blooms would be increased after the Baqing River water transfer project even with the improved water quality. Algae gained faster proliferation with the same dominant species in water transfer source. Therefore, water transfer projects should be assessed from not only the variation of water quality but also the risk of algal blooms.

关键词： Water transfer Water quality Phytoplankton community Algal blooms Algal growth potential Chenghai Lake

Pre-oxidation enhanced cyanobacteria removal in drinking water treatment: A review

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Journal of Environmental Sciences 2021年第12期33卷 160-168页

作者： jing qi Baiwen Ma Shiyu Miao Ruiping Liu Chengzhi Hu Jiuhui Qu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Cyanobacterial bloom has many adverse effects on source water quality and drinking water production. The traditional water treatment process can hardly achieve satisfactory removal of algae cells. This review examines the impact of pre-oxidation on the removal of cyanobacteria by solid-liquid separation processes. It was reported that the introduction of chemical oxidants such as chlorine, potassium permanganate, and ozone in algae-laden water pretreatment could improve algae removal by the subsequent solid-liquid separation processes. However, over dosed oxidants can result in more serious water quality risks due to significant algae cell lysis and undesirable intracellular organic matter release. It was suggested that moderate pre-oxidation may enhance the removal of cyanobacteria without damaging algae cells. In this article, effects of moderate pretreatment on the solid-liquid separation processes(sedimentation, dissolved air flotation, and membrane filtration) are reviewed.

关键词： Cyanobacterial bloom Pre-oxidation Sedimentation Dissolved air flotation Membrane filtration

SIGNAL CONSTELLATIONS DESIGN FOR DIFFERENTIAL UNITARY SPACE-TIME IN MIMO-OFDM SYSTEM OVER FREQUENCY-SELECTIVE FADING CHANNELS

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Journal of Electronics(China) 2008年第3期25卷 300-304页

作者： Chen jing Zhu qi College of Communication ＆ Information Engineering Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

In this paper, the design of signal constellations parameters is studied for Differential Unitary Space-Time Modulation (DUSTM) based on the design criterion of maximizing the diversity product. Further, noninteger searching method for the signal constellation parameters design is proposed in order to get better codes. Experimental results show that under the different Doppler spread and data transmission rate, the proposed design performs better than the previous design using integer parameters in Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system over frequency-selective fading channels.

关键词： Differential Unitary Space-Time Modulation (DUSTM) Diversity product Signal constellations Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Mutiplexing (OFDM)

Studying the localized CP violation and the branching fraction of the B^0→K^-π^+π^+π^-decay

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Chinese Physics C 2020年第10期44卷 51-58页

作者： jing-Juan qi Zhen-Yang Wang jing Xu Xin-Heng Guo Junior College Zhejiang Wanli UniversityZhejiang 315101China Physics Department Ningbo UniversityZhejiang 315211China Department of Physics Yantai UniversityYantai 264005China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China

In this work,we study the localized CP violation and the branching fraction of the four-body decay^ˉB 0→K^−π^+π^−π^+by employing a quasi-two-body QCD factorization *** the interference of^ˉB 0→ˉK^∗0(700)ρ0(770)→K^−π^+π^−π^+and^ˉB 0→ˉK∗(892)f0(500)→K^−π^+π^−π^+channels,we predict ACP(^ˉB 0→K^−π^+π^−π^+)∈[0.15,0.28]and B(^ˉB 0→K^−π^+π^−π^+)∈[1.73,5.10]×10^−7,respectively,which shows that the interference mechanism of these two channels can induce the localized CP violation to this four-body ***,within the two quark model framework for the scalar mesons f0(500)andˉK^∗0(700),we calculate the direct CP violations and branching fractions of the^ˉB 0→ˉK^∗0(700)ρ0(770)and^ˉB 0→ˉK∗(892)f0(500)decays,*** corresponding results are ACP(^ˉB 0→ˉK^∗0(700)ρ0(770))∈[0.20,0.36],ACP(^ˉB 0→ˉK∗(892)f0(500))∈[0.08,0.12],B(^ˉB 0→ˉK^∗0(700)ρ0(770)∈[6.76,18.93]×10^−8 and B(^ˉB 0→ˉK∗(892)f0(500))∈[2.66,4.80]×10^−6,indicating that the CP violations of these two-body decays are both positive and the branching fractions quite *** studies provide a new way to investigate the aforementioned four-body decay and can be helpful in clarifying the configuration of the structure of the light scalar meson.

关键词： decays of bottom mesons CP violation perturbative calculations

A NEW WELL TEST MODEL FOR STRESS-SENSITIVE AND RADIALLY HETEROGENEOUS DUAL-POROSITY RESERVOIRS WITH NON-UNIFORM THICKNESSES

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Journal of Hydrodynamics 2011年第6期23卷 759-766页

作者： ZHANG Lie-hui, GUO jing-jing, LIU qi-guo State Key Laboratory of Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China State Key Laboratory of Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China

This article presents a new well test model for stress-sensitive composite dual-porosity reservoirs based on the concept of permeability modulus, where the rock and fluid properties as well as the formation thickness vary in the radial direction. An analytical solution in the Laplace space for the pressure-transient behavior for a line-source, constant-rate well of this type of reservoir is obtained with the Laplace transformation and the perturbation technique. The pressure and its derivative in the reservoir and the effects of relevant parameters on the pressure-transient response are obtained. The model as well as the corresponding type curves may be used in predicting the production performance or analyzing the production data for this type of reservoir.

关键词： non-uniform thickness stress-sensitive composite dual-porosity well test model type curve

Design and modulation principles of molybdenum carbide-based materials for green hydrogen evolution

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Journal of Energy Chemistry 2020年第9期29卷 398-423,I0012页

作者： jing-qi Chi Min Yang Yong-Ming Chai Zhi Yang Lei Wang Bin Dong State Key Laboratory of Heavy Oil Processing College of ScienceChina University of Petroleum(East China)Qingdao 266580ShandongChina Key Laboratory of Thin Film and Microfabrication(Ministry of Education) Department of Micro/Nano ElectronicsSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shandong Key Laboratory of Biochemical Analysis College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongChina

The green production of hydrogen from electrocatalytic water splitting is an important base and promising direction for the future of the large-scale application of hydrogen *** key of green hydrogen evolution depends on the development of low-cost and highly active *** carbides(MoxC),as a typical of earth-abundant transition-metal material,have accumulated great attention due to their low cost,earth abundance,electrical conductivity,similar d-band state to Pt,and regulated morphology/electronic *** this paper,recent researches focusing on MoxC for efficient HER in a wide pH range are summarized from respects of modulation of unique morphology,electronic structure,and electrode interface step by ***,modulation of morphology influence the apparent activity of catalyst,modulation of electronic structure of active sites by heteroatom doping and designing heterointerface boost intrinsic HER kinetics,and modulation of electrode interface via hybridization of MoxC structures with carbon materials can ensure the fast electron transfer and boost the *** the above methods discussed,perspective and challenges of designing MoxC as the substitute of Pt-based electrocatalyst for practical hydrogen generation in a wide pH range are pointed out.

关键词： Molybdenum carbides Classification Electrocatalyst Modulation strategy Hydrogen evolution