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Conversion of carbonaceous materials into solid acids for tylosin mitigation:effect of preprocessing methods on the reactivity of sulfonation reaction

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Biochar 2023年第1期5卷 558-573页

作者： Chunmei Wang Qianqian xie Xiaomin Dou lanxi Zhang Xiao Yang College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083People’s Republic of China Key Laboratory of land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China

Carbon-based solid acids have been successfully employed as acidic catalysts for pollutant mitigation in *** fully tap the potentials of commercially viable carbons for the preparation of solid acids and enhance their catalytic performances is a challenging *** this work,three commercialized carbons including biochar,activated carbon and graphite were preprocessed(ball-milling,Hummer exfoliation,HNO3 soaking,and microwave heating in HNO_(3),etc.),sulfonated,and evaluated as solid-acid catalysts for tylosin ***-originated solid acid performed the best through a balling-milling preprocess,while biochar-originated solid acids behaved well under all preprocessing treatments,in which 40 mg L^(−1) of tylosin was mitigated within 8 min by 1 g L^(−1) of biochar-originated solid *** biochar solid acid through the ball-milling preprocess presented high total acidity and large amounts of-SO_(3)H groups,due to dramatically increased surface area and the rise of activation groups(hydroxyl,alkyl and alkoxy groups,etc.)facilitating electrophilic *** addition,decreased particle size and aromaticity and increased structural defects also *** calculation of average local ionization energy(ALIE)of condensed aromatic model molecules with substituted activation groups confirmed the promoting effects on sulfonation from strong to weak were 8.40-9.06 *** findings have deepened the knowledge in tuning carbon surface chemistry for better sulfonation,thus strengthening catalytic degradation of *** value of this study is in pulling a clear thread for maneuvering solid-acid catalysts using carbons,which holds a novel promise for rationally functionalizing biochar-based catalysts for the remediation of macrolide antibiotics in polluted water.

关键词： Biochar engineering Sulfonation Heterogeneous catalysis Tylosin hydrolysis Antibiotic remediation

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A Novel Two-Layer Model for Overall Quality Assessment of Multichannel Audio

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China Communications 2017年第9期14卷 42-51页

作者： Jiyue Liu Jing Wang Min Liu Xiang xie Jingming Kuang School of Information and Technology Beijing Institute of Technology

With the development of multichannel audio systems, corresponding audio quality assessment techniques, especially the objective prediction models, have received increasing attention. Existing methods, such as PEAQ(Perceptual Evaluation of Audio Quality) recommended by ITU, usually lead to poor results when assessing multichannel audio, which have little correlation with subjective scores. In this paper, a novel two-layer model based on Multiple Linear Regression(MLR) and Neural Network(NN) is proposed. Through the first layer, two indicators of multichannel audio, Audio Quality Score(AQS) and Spatial Perception Score(SPS) are derived, and through the second layer the overall score is output. The final results show that this model can not only improve the correlation with the subjective test score by 30.7% and decrease the Root Mean Square Error(RMSE) by 44.6%, but also add two new indicators: AQS and SPS, which can help reflect the multichannel audio quality more clearly.

关键词： multichannel audio two-layermodel audio quality assessment multiple lin-ear regression neural network

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Effect of symmetrical frequency chirp on pair production

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Chinese Physics B 2021年第6期30卷 96-105页

作者： Kun Wang Xuehua Hu Sayipjamal Dulat Bai-Song xie School of Physics and Technology Xinjiang UniversityUrumqi 830046China Key Laboratory of Beam Technology of the Ministry of Education and College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Beijing Radiation Center Beijing 100875China

By using Dirac–Heisenberg–Wigner formalism we study electron–positron pair production for linear, elliptic, nearly circular, and circular polarizations of electric fields with symmetrical frequency chirp, and we obtain momentum spectra and pair yield. The difference of results among polarized fields is obvious for the small chirp. When the chirp parameter increases, the momentum spectra tend to exhibit the multiphoton pair generation that is characterized by the multi-concentric ring structure. The increase of the number density is also remarkable compared to the case of asymmetrical frequency chirp. Note that the dynamically assisted Schwinger mechanism plays an important role for the enhanced pair production in the symmetrical frequency chirp.

关键词： pair production Dirac–Heisenberg–Wigner formalism symmetrical frequency chirp

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Achievable Uplink Rate Analysis for Distributed Massive MIMO Systems with Interference from Adjacent Cells

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China Communications 2017年第5期14卷 112-123页

作者： Xiangdong Jia Mangang xie Meng Zhou Hongbo Zhu Longxiang Yang College of Computer Science and Engineering Northwest Normal University Wireless Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications

This work focuses on the multicell multi-user distributed massive MIMO(DM-MIMO)systems,of which each user is equipped with single antenna and the base stations(BSs)consists of distributed antenna units. We first investigate the arbitrary BS antenna topology scenario. The derivation indicates that in this case the achievable uplink rate of an arbitrary user in central cell depends on both the number of BS's antennas and the users' access distance to each distributed antenna unit(DAU). As a result,the performance analysis based on the derivations is difficult. To overcome this issue and achieve clearer insight,we then consider a circularly distributed BS antenna array and obtain the asymptotic uplink rate of an arbitrary user by considering the asymptotic case where the number of antennas of BSs tends to infinity. It is achieved that the asymptotic uplink rate only depends on the distance from users' position to the center of reference cell. The presented numerical results show clearly that the distributed massive MIMO systems outperform the centralized ones. Moreover,it is also achieved that the interference from the adjacent cells imposes great impact on system performance. Besides this,in numerical analysis the averageasymptotic uplink rate of a user is presented,which is free of the users' position and only depends on the radius of circular antenna arrays. It is achieved the maximum average uplink rate would be achieved when the radius of circularly distributed antenna array goes to its optimization location.

关键词： wireless communications massive MIMO distributed antenna array ergodic rate adjacent cell interference

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The preface: Toward higher-Tc superconductivity under lower pressure——from binary to ternary superhydrides

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National Science Review 2024年第7期11卷 7-8页

作者： Fu-Chun Zhang Ho-kwang Mao Xin-Cheng xie Kavli Institute for Theoretical Sciences University of Chinese Academy of Sciences Shanghai Advanced Research in Physical Sciences Center for High Pressure Science and Technology Advanced Research International Center for Quantum Materials School of Physics Peking University

Superconductivity——the phenomenon of complete vanishing of electrical resistance and expulsion of magnetic field——is the paramount electromagnetic property for technological advancement that is only shackled by th...

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A Soil Moisture Data Assimilation System for Pakistan Using PODEn4DVar and CLM4.5

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Journal of Meteorological Research 2019年第6期33卷 1182-1193页

作者： Tariq MAHMOOD Zhenghui xie Binghao JIA Ammara HABIB Rashid MAHMOOD State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Pakistan Meteorological Department Islamabad 44000Pakistan Key Laboratory of Water Cycle and Related land Surface Processes Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Soil moisture is an important state variable for land–atmosphere *** is a vital land surface variable for research on hydrology,agriculture,climate,and drought *** current study,a soil moisture data assimilation framework has been developed by using the Community land Model version 4.5(CLM4.5)and the proper orthogonal decomposition(POD)-based ensemble four-dimensional variational assimilation(PODEn4 DVar)*** experiments were conducted at four agricultural sites in Pakistan by assimilating in-situ soil moisture *** results showed that it was a reliable *** quantify further the feasibility of the data assimilation(DA)system,soil moisture observations from the top four soil-depths(0–5,5–10,10–20,and 20–30 cm)were *** evaluation results indicated that the DA system improved soil moisture *** addition,updating the soil moisture in the upper soil layers of CLM4.5 could improve soil moisture estimation in deeper soil layers[layer 7(L7,62.0 cm)and layer 8(L8,103.8 cm)].To further evaluate the DA system,observing system simulation experiments(OSSEs)were designed for Pakistan by assimilating daily *** idealized experiments produced statistical results that had higher correlation coefficients,reduced root mean square errors,and lower biases for assimilation,which showed that the DA system is able to produce and improve soil moisture estimation in Pakistan.

关键词： PODEn4DVar Community land Model version 4.5 data assimilation soil moisture Pakistan

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The effect of applied potential on stress corrosion cracking of X80 pipeline steel in acidic soil containing sulfate-reducing bacteria

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Science China(Technological Sciences) 2023年第10期66卷 2837-2849页

作者： HE JianYu xie Fei ZHAO Yang GUO DaCheng WANG Dan LI JunChi College of Petroleum Engineering Liaoning Petrochemical UniversityFushun 113001China Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun 113001China Liaohe Oilfield Oil and Gas Gathering and Transmission Company Panjin 124000China Northeast Natural Gas Sales Center Sinopec Natural Gas BranchShenyang 110100China

Electrochemical experiments,slow strain rate tensile testing(SSRT),and scanning electron microscopy were used to investigate the effect of various applied potentials on the stress corrosion cracking(SCC)of X80 pipeline steel in acidic soil containing sulfate-reducing bacteria(SRB).The results demonstrated that when the anodic potential was applied,X80 steel exhibited sensitivity to SCC,which was attributed to anodic *** SCC sensitivity initially decreased,but then increased with a negative shift in the applied ***-1200 mV,SCC was the most sensitive,which corresponded to the substantial cathodic polarisation and toxic impact of SRB,which increased the risk of hydrogen ***-850 mV,the SCC sensitivity was the lowest because cathodic polarisation suppressed anodic *** experimental results can contribute to the prevention and management of SCC in operational pipelines.

关键词： applied potential acid soil SCC sulfate-reducing bacteria

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Synthesis,Crystal Structure and Quantum Chemical Investigation of Bis-Schiff Base Compounds Derived from2-phenyl-1,2,3-triazole-4-carboxaldehyde with Diamine

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Chinese Journal of Structural Chemistry 2008年第5期27卷 616-621页

作者： xie Ling LIU Gang WANG Yan WANG Ji-De CHEN Jun-Feng Department of Chemistry Key Laboratory of Oil ＆ Gas Fine Chemicals Ministry of Education Xinjiartg University Urumqi 830046 China

Two new schiff base N,N＇-bis（（2-phenyl-2H-1,2,3-triazol-4-yl）methylene）-1,3-propanediamine （1） and N,N＇-bis（（2-phenyl-2H-1,2,3-triazol-4-yl）methylene） -1,4-butanediamine （2） were synthesized by condensation of 2-phenyl-1,2,3-triazole-4-carboxaldehyde with diamine, and characterized by elemental analysis, IR, IH NMR and MS spectra. Their crystal structures were determined by X-ray single crystal diffraction. Both crystals belong to the monoclinic system, space group P21/c. For compound 1（C21H20N8, Mr=384.45）： a = 16.314（3）, b =5.7168（11）, c = 21.316（4） A, β = 105.3（2）°, Z = 4, V = 1917.6（7） A^3, De =1.332 g/cm^3, F（000） = 808,μ = 0.086 mm 1, R = 0.0533 and wR = 0.1460; for compound 2 （C22H22N8, Mr=398.48）： a = 8.6156（17）, b = 5.2964（11）, c = 22.665（5）A, β = 100.54（3）°, Z = 2, V = 1016.8（4） A^3, De= 1.302 g/cm^3, F （000） = 420, μ = 0.083 mm^-1, R = 0.0373 and wR = 0.1155. Based on the crystal data, quantum chemistry calculation was performed on the two title compounds by means of Gaussian 98 program. The molecular orbital energies and atomic net charges population were obtained. Furthermore, we antilyzed their active atoms. The investigation can serve as a theoretical guide to study the synthesis and activity of the title compounds.

关键词： schiff base crystal structure quantum chemical calculation

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Digital Element Earth

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 1-16页

作者： xie Xuejing WANG Xueqiu CHENG Hangxin CHENG Zhizhong YAO Wensheng Institute of Geophysical and Geochemical Exploration CAGS 84 Jinguang Road Langfang Hebei Province 065000 China

The resources and environmental problems are the two most fundamental issues facing all nations in the world. Everything in and on the Earth - minerals, animals and plants -is made from one, or generally some combination of, chemical elements, which are scientifically listed in the periodic table. Thus it is important to understand the present abundance and spatial distribution of all the elements across the Earth＇s surface. Such kinds of data can only be obtained at present and for the foreseeable future by on-earth geochemical mapping at all scales. The 30-year efforts made by Chinese geochemists in carrying out multi-element, multi-media, multi-scale geochemical mapping projects to delineate 39-76 element distribution at home and abroad culminated in a successful case of high- quality geochemical data acquirement. The new idea for a four-level plan for global geochemical mapping was advanced to obtain global data in the foreseeable future and the collection of updated geochemical information. Such information needs to be easily accessible not only by the science community, but also by industry, agriculture, governments, and even individuals, by all who would make an effort to promote sustainable riving on our planet. The concept of a Digital Element Earth （DEE） fulfills the aims.

关键词： Digital Element Earth chemical elements geochemical mapping sustainable development

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The correlation between expansion speed and magnetic field in solar flare ribbons

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1754-1759页

作者： xie WenBin WANG HaiMin JING Ju BAO XingMing ZHANG HongQi Key Laboratory of Solar Activity National Astronomical Observatories of ChinaBeijing 100012China Physics Department New Jersey Institute of TechnologyNewarkNJ07102USA Jilin Normal University Jilin 136000China

In this paper, we study the correlation between the expansion speed of two-ribbon flares and the magnetic field measured in the ribbon location, and compare such correlation for two events with different magnetic configurations. These two events are: an M1.0 flare in the quiet sun on September 12, 2000 and an X2.3 flare in Active Region NOAA 9415 on April 10, 2001. The magnetic configuration of the M1.0 flare is simple, while that of X2.3 event is complex. We have derived a power-law correlation between the ribbon expansion speed (V r) and the longitudinal magnetic field (Bz) with an empirical relationship V r = A×Bz-δ, where A is a constant and δ is the index of the power-law correlation. We have found that δ for the M1.0 flare in the simple magnetic configuration is larger than that for the X2.3 flare in the complex magnetic configuration.

关键词： solar activity solar flares solar magnetic field

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