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Kinetics and mechanisms of reactions for hydrated electron with chlorinated benzenes in aqueous solution

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Frontiers of Environmental Science & Engineering 2015年第4期9卷 583-590页

作者： Haixia YUAN Huxiang PAN jin shi Hongjing LI Wenbo DONG Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science & Engineering Fudan University Shanghai 200433 China Institutes of Naval Medicine Shanghai 200433 China

The reactions between chlorinated benzenes （CBzs） and hydrated electron （eaq^-） were investigated by the electron beam （EB） and laser flash photolysis （LFP） experiments. Under the EB irradiation, the effects of irradiation dose, initial concentration and the number of Cl atoms on the removal efficiencies were further examined. At 10 kGy, the removal efficiencies of mono-CB, 1,3-diCB, 1,2-diCB and 1,4-diCB were 41.2%, 87.2%, 84.0%, and 84.1%, respectively. While irradiation dose was 50 kGy, the removal efficiencies increased to 47.4%, 95.8%, 95.0%, and 95.2%, respectively. Irradiation of CBzs solutions has shown that the higher the initial concentration, the lower the percentage of CBzs removal. In addition to this, the dechlorination efficiencies of 1,2-dichlorobenzene （1,2-diCB）, 1,3-dichlorobenzene （1,3-diCB） and 1,4-dichlorobenzene （1,4-diCB） were much higher than that of chlorobenzene （mono-CB）. The kinetics of the reactions was achieved with nanosecond LFP. The rate constants of second-order reaction between eaq^- with mono-CB, 1,2-diCB, 1,3-diCB and 1,4-diCB were （5.3±0.4） × 10^8, （4.76±0.1） × 10^9, （1.01±0.1） × 1010 and （3.29±0.2） × 10^9 L·mol^-1·s^-1, respectively. Density functional theory （DFT） calculations were performed to determine the optical properties of unstable CBzs anion radicals, and the main absorption peaks lied in the range of 300–550 nm. The primary reaction pathway of CBzs with eaq^- was gradual dechlorination, and the major products were Cl^- and benzene （CBzs（-Cl^-））. Furthermore, biphenyl （or chlorobiphenyl） was observed during the LFP, which was probably formed by recombination of benzene radicals.

关键词： chlorinated benzenes hydrated electron electron beam laser flash photolysis

Synthesis and Photochemistry of Diphenylchlorin and Diphenylbacteriochlorin

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Chinese Chemical Letters 2001年第8期12卷 671-674页

作者： Tian Yu WANG jing Rong CHEN jin shi MA Center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080 Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100101

Diphenylchlorin (DPC) and diphenylbacteriochlorin (DPBC) were synthesized for the first time from reduction of 5,10-diphenylporphyrin (DPP). As photosensitizers they have sizable absorption in the red region of the visible spectrum. The high yield of DPC.-photosensitized generation Of O-1(2), and the EPR studies in homogenerous solution showed that the photodynamic action of DPP-based photosensitizers may proceed via type I and type II machanisms.

关键词： Diphenylchlorin diphenylbacteriochlorin synthesis photochemistry

Deep learning for joint channel estimation and feedback in massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 83-93页

作者： Jiajia Guo Tong Chen shi jin Geoffrey Ye Li Xin Wang Xiaolin Hou National Mobile Communications Research Laboratory Southeast UniversityNanjing210096China Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZUK DOCOMO Beijing Communications Laboratories Co. LtdBeijingChina

The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base ***,the accurate CsI is difficult to obtain due to the large amount of feedback overhead caused by massive *** this paper,we propose a deep learning based joint channel estimation and feedback framework,which comprehensively realizes the estimation,compression,and reconstruction of downlink channels in FDD massive MIMO *** networks are constructed to perform estimation and feedback explicitly and *** explicit network adopts a multi-Signal-to-Noise-Ratios(SNRs)technique to obtain a single trained channel estimation subnet that works well with different SNRs and employs a deep residual network to reconstruct the channels,while the implicit network directly compresses pilots and sends them back to reduce network *** module is also designed to generate data-bearing *** results show that the two proposed networks exhibit excellent performance of reconstruction and are robust to different environments and quantization errors.

关键词： Channel estimation CSI feedback Deep learning Massive MIMO FDD

BOUNDARY VALUE PROBLEM FOR NON-LINEAR SECOND ORDER ORDINARY DIFFERENTIAL EQUATION WITH DISCONTINUOUS TERMS IN BANACH SPACE

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Analysis in Theory and Applications 2009年第4期25卷 349-354页

作者： jin＇e shi Guozhong Cui Information and Engnieerin g University China

By using upper and lower solutions and fixed point theorem we give the existence theorem of non-linear second order ordinary differential equation with discontinuous terms in Banach Space.

关键词： method of upper and lower solutions decreasing operator fixed point mono-tone operator

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五边形石墨烯氧气吸附与解离特性研究

原子与分子物理学报 2025年第4期42卷 40-44页

作者：吴旌贺丁雅妮郭梦雨陈卫光史金磊河南财政金融学院创新创业学院郑州450046 郑州师范学院物理与电子工程学院郑州市低维纳米材料重点实验室郑州450044

基于密度泛函理论的第一性原理计算方法,研究了O_(2)在五边形石墨烯(PG)上的吸附与解离动力学行为.研究结果表明,PG并不能有效地激发O_(2),形成稳定的氧吸附结构需要克服约0.54 eV势垒,并且吸附的O_(2)分解需要克服约0.82 eV势垒.然而,O... 详细信息

基于密度泛函理论的第一性原理计算方法,研究了O_(2)在五边形石墨烯(PG)上的吸附与解离动力学行为.研究结果表明,PG并不能有效地激发O_(2),形成稳定的氧吸附结构需要克服约0.54 eV势垒,并且吸附的O_(2)分解需要克服约0.82 eV势垒.然而,O_(2)分解后的PG衬底结构却能使后续吸附的O_(2)分子自动分解,破坏C-C键,以致PG在空气中难以稳定存在.基于此,为了避免PG结构在空气中被氧化,我们进一步提出将过渡金属原子吸附PG,使得O_(2)更容易被过渡金属原子吸附与激发,从而避免了PG被氧化.

关键词：五边形石墨烯 O_(2)吸附与解离第一性原理计算

Impacts of Model Mismatch and Array Scale on Channel Estimation for XL-HRIS-Aided Systems

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ZTE Communications 2024年第1期22卷 24-33页

作者： LU Zhizheng HAN Yu jin shi National Mobile Communications Research Laboratory Southeast Uni-versityNanjing 210096China

Extremely large-scale hybrid reconfigurable intelligence surface(XL-HRIS),an improved version of the RIS,can receive the incident signal and enhance communication ***,as the RIS size increases,the phase variations of the received signal across the whole array are nonnegligible in the near-field region,and the channel model mismatch,which will decrease the estimation accuracy,must be *** this paper,the lower bound(LB)of the estimated parameter is studied and the impacts of the distance and signal-tonoise ratio(SNR)on LB are then ***,the impacts of the array scale on LB and spectral efficiency(SE)are also *** results verify that even in extremely large-scale array systems with infinite SNR,channel model mismatch can still limit estimation ***,this impact decreases with increasing distance.

关键词： XL-HRIS near-field LB model mismatch parameter estimation

NETWORK-CONNECTED UAV COMMUNICATIONS

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China Communications 2018年第5期15卷 I0003-I0005页

作者： Yong Zeng shi jin Qihui Wu Feifei Gao the National University of Singapore the faculty of the National Mobile Communications Research Laboratory Southeast University the College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics the Department of Automation Tsinghua University

Unmanned aerial vehicles(UAVs)have found fast growing applications in recent years,such as for cargo delivery,precision agriculture,aerial monitoring,video streaming,traffic control,rescue and search,and communication... 详细信息

关键词：连接网络通讯 UAV 精确农业交通控制天线搜索

Structure of Micro-nano WC-10Co4Cr Coating and Cavitation Erosion Resistance in NaCl Solution

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1239-1247页

作者： Xiang Ding Xu-Dong Cheng Cheng-Qing Yuan jin shi Zhang-Xiong Ding State Key Laboratory of Advanced Technology for Materials and Processing Wuhan University of Technology School of Energy and Power Engineering Wuhan University of Technology

Cavitation erosion （CE） is the predominant cause for the failure of overflow components in fluid machinery. Advanced coatings have provided an effective solution to cavitation erosion due to the rapid development of surface engineering techniques. However, the influence of coating structures on CE resistance has not been sys- tematically studied. To better understand their relationship, micro-nano and conventional WC-10Co4Cr cermet coat- ings are deposited by high velocity oxygen fuel spray- ing（HVOF）, and their microstructures are analyzed by OM, SEM and XRD. Meanwhile, characterizations of mechan- ical and electrochemical properties of the coatings are carried out, as well as the coatings＇ resistance to CE in 3.5 wt % NaC1 solution, and the cavitation mechanisms are explored. Results show that micro-nano WC-10Co4Cr coating possesses dense microstructure, excellent mechanical and electrochemical properties, with very low porosity of 0.26 4-0.07% and extraordinary fracture toughness of 5.58 4-0.51 MPa.m1/2. Moreover, the CE resistance of micro-nano coating is enhanced above 50% than conventional coating at the steady CE period in 3.5 wt % NaC1 solution. The superior CE resistance of micro- nano WC-10Co4Cr coating may originate from the unique micro-nano structure and properties, which can effectively obstruct the formation and propagation of CE crack. Thus,a new method is proposed to enhance the CE resistance of WC-10Co4Cr coating by manipulating the microstructure.

关键词： Cavitation erosion resistance Micro-nanostructure - WC- 10Co4Cr coating HVOF

[0001]-Oriented InN Nanoleaves and Nanowires: Synthesis,Growth Mechanism and Optical Properties

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 820-826页

作者： Min Liu Hui-Qiang Liu Sheng Chu Ru-Fang Peng shi-jin Chu State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials Southwest University of Science and Technology State Key Laboratory of Optoelectronic Materials and Technology Sun Yat-Sen University

Novel indium nitride （INN） leaf-like nanosheets and nanowires have been grown on Si substrate by chemical vapor deposition method. The characterization results indicate that the samples are single-crystalline, and the growth direction of the nanowires and nanoleaves is [0001]. The growth mechanism of the InN nanoleaves is following the pattern of vapor-liquid-solid process with a three-step growth process. In addition, the room temperature photoluminescence spectra of two nanostructures show band-to-band emissions around 0.706 eV, where the emission from single nanoleaf is stronger than nanowire, showing potential for applications in optoelectronic devices.

关键词： Novel indium nitride (INN) Chemical vapor deposition (CVD) Nanoleaf Crystal structure Photoluminescence (PL)