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Chemical Research in Chinese Universities 2014年第5期30卷 806-810页

作者： long wen xu Huawei HE Tianmin Key Laboratory of Physics and Technology for Advanced Batteries Ministry of Education College of Physics Jilin University Changchun 130012 P. R. China

Perovskite oxide Ba0.5Sr0.5Fe0.9Nb0.1O3-δ（BSFN） as a cobalt-free cathode for intermediate-temperature solid oxide fuel cells（IT-SOFCs） on the Ce0.5Sm0.2O1.9（SDC） and La0.9Sr0.1Ga0.8Mg0.23O3-δ（LSGM） electrolytes was prepared and investigated. The single phase BSFN oxide with a cubic perovskite structure and relatively high elec- trical conductivities was obtained after sintering at 1250℃ for 10 h in air. The BSFN cathode exhibited excellent chemical stability on the SDC and LSGM electrolytes at temperatures below 950 ℃. The area specific resistance of the BSFN cathode on the SDC and LSGM electrolytes were 0.024 and 0.021 Ω·cm2 at 800℃, respectively. The maximum power densities of the single cell with BSFN cathode in 300 μm-thick SDC and LSGM electrolytes achieved 414 and 516 mW/cm2 at 800℃, respectively. These results show that the BSFN material is a promising co- bait-free cathode candidate to be used in IT-SOFCs. A combination of the BSFN cathode and LSGM electrolyte is preferred owing to its excellent electrochemical performance.

关键词： Solid oxide fuel cell Cathode Phase formation Chemical stability Electrochemical performance

Bore-center annular shaped charges with different liner materials penetrating into steel targets

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Defence Technology（防务技术） 2019年第5期15卷 796-801页

作者： wen-long xu Cheng Wang Jian-ming Yuan Tao Deng State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Temasek Laboratories Nanyang Technological University50 Nanyang Drive637553Singapore

The bore-center annular shaped charge(BCASC)is a new type of shaped charge which can generate a larger-diameter hole in steel targets than classical shaped *** this paper,the influence of three liner materials,***,nickel and copper,on BCASC formation and penetrating into steel targets was investigated by experiment and numerical *** simulation results were well consistent with the experimental *** study showed that,at 0.50D standoff distance,the axial velocity of the molybdenum projectile was lower than that of the nickel and copper *** nickel and copper projectiles had almost the same head *** absolute values of the radial velocity of the molybdenum projectile head was lower than that of the nickel and copper ***,at 0.75D standoff distance,the absolute values of the radial velocity of the molybdenum projectile head became much greater than that of the nickel and copper projectile *** projectile formed by BCASC with the molybdenum liner had the highest penetration depth of 61.5 mm,which was 10.0%and 21.3%higher than that generated by the copper and nickel projectiles.

关键词： Annular shaped charge Liner material Formation Numerical simulation

Investigation on energy output structure of explosives near-ground explosion

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Defence Technology（防务技术） 2020年第2期16卷 290-298页

作者： wen-long xu Cheng Wang Jian-ming Yuan Wei-liang Goh Tao Li State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Temasek Laboratories Nanyang Technological University50 Nanyang Drive637553Singapore

In order to give the energy output structure of typical explosives near-ground explosion in real ground conditions,the free-field shockwave,ground reflection shockwave and Mach wave overpressure time history of composition B explosive,RDX explosive and aluminized explosive were measured by air pressure sensors and ground pressure *** shape of the free-field shock wave,ground reflection shock wave,and Mach wave and explosion flame were captured by high-speed *** experimental results show that,at the same horizontal distance from the initiation point,the peak overpressure of explosive shock wave of composition B explosive,both in the air and on the ground,is less than that of RDX and aluminized *** a distance of 3.0 m from the initiation point,the peak overpressure of aluminized explosives is slightly less than that of RDX *** to the exothermic effect of aluminum powder,the pressure drop of aluminized explosives is slower than that of RDX *** 5.0 m from the initiation point,the peak overpressure of aluminized explosives is larger than that of RDX *** the same position from the initiation point,among the three kinds of explosives,the impulse of aluminized explosives is the maximum and the impulse of composition B explosives is the *** the increase of the horizontal distance from the initiation point,the height of Mach triple-points(Mach steam)of the three explosives increases *** the same horizontal distance from the initiation point,there is poorly difference in the height of Mach triple-points between aluminized explosive and RDX explosive,and the height of Mach triple-points of composition B explosive is much smaller than that of other two *** maximum diameter and duration of the fireball formed by aluminized explosives are the largest,followed by composition B explosive,and the maximum diameter and duration of the fireball formed by RDX explosive are the smallest.

关键词： Near-ground blast Reflected wave Marcher steam Aluminized explosives

Chitin-derived fibrous carbon microspheres as support of polyamine for remarkable CO_(2) capture

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Green Chemical Engineering 2022年第3期3卷 267-279页

作者： wen-long xu Hui-Jie Chen Yi-Chao Wang Shuai Liu Xin-Yi Wan Hai-long Peng Kuan Huang School of Resources Environmental and Chemical Engineering Nanchang UniversityNanchang330031China National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou350002China

Supported polyamines are promising candidates for the chemical adsorption of CO_(2),the performance of which is highly dependent on the porous structure of *** this work,we synthesized a kind of fibrous carbon microspheres(FCMs)from environmentally friendly and low-cost *** synthesized FCMs have microspheric morphology and fibrous sub-architecture,and the carbon fibers interweave to form pores with large *** flexibility of the pores formed by the interweaving of carbon fibers also enable the supporting of high quantity of *** these features,pentaethylenehexamine(PEHA)was physically dispersed in the pores of FCMs to prepare PEHA/FCMs adsorbents,which were systematically characterized and investigated for CO_(2) capture *** is found that PEHA/FCMs adsorbents show excellent ability for CO_(2) adsorption,with the highest CO_(2) capacity of 3.90 mmol g^(-1) at 75℃ when using 10 vol%of CO_(2) for *** reversibility of PEHA/FCMs adsorbents for CO_(2) adsorption is also fairly good,and PEHA/FCMs adsorbents have strong ability for the selective adsorption of low-content CO_(2) from N_(2).

关键词： CO_(2)capture Supported polyamine Fibrous carbon Carbon microsphere Chemical adsorption

Sulfonated poly(aryl ether ketone sulfone)modified by polyoxometalates LaW_(10) clusters for proton exchange membranes with high proton conduction performance

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Tungsten 2024年第2期6卷 454-464页

作者： Meng-long Liu xu Han wen-wen He Feng-Yu Jiang Fang Ji Wang-Wang Shen Tao Zhou Jing-Mei xu Ya-Qian Lan School of Chemistry and Life Science Changchun University of TechnologyChangchun 130012China Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China School of Chemistry South China Normal UniversityGuangzhou 510006China

Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membranes(PEMs).In this study,a series of hybrid membranes were obtained by molecular-level hybridization of Weakley-type POM Na_(7)H_(2)LaW_(10)O_(36)(LaW_(10))clusters into sulfonated poly(aryl ether ketone sulfone)(SPAEKS).All hybrid membranes exhibited greater proton conductivity than the pristine membrane in the 30–80℃temperature *** the doping amount of LaW 10 reached 7 wt.%,the proton conductivity of M-LaW 10^(-7)achieved 64 mS·cm^(−1)at 80℃.Lanthanide ions'high coordination number property and variable coordination environment can aid to attract more water molecules from the *** 10 and these bound water can construct denser hydrogen bonds with–SO_(3)H of *** intensive hydrogen bonds will facilitate the constitution of more continuous proton transport channels,and improve the proton conductivity of the hybrid *** work off ers a fresh approach to using POMs containing rare-earth components in PEMs.

关键词： Polyoxometalates Rare-earth elements Sulfonated poly(arylene ether ketone sulfone) Proton exchange membranes

A Risk Score System for Myopia Symptom Warning

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Current Medical Science 2019年第3期39卷 455-462页

作者： Dan-dan DU wen-long xu Li-hua YANG He-xin WANG Chang-mei GU Jia TANG Fang LI Ting xu Shi-qing WU Mei-xia LU Department of Epidemiology and Statistics and the Ministry of Education (MOE) Key Lab of Environment and Health School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Wuhan Center for Adolescent Poor Vision Prevention & Control Wuhan 430015 China Wuhan Commission of Experts for the Prevention &. Control of Adolescent Poor Vision Wuhan 430015 China China Innovation and Research and Development Center Carl Zeiss (Shanghai) Co. Ltd. ZEISS Group Shanghai 200131 China Wuhan Academy of Educational Science Wuhan 430030China Wuhan Centers for Disease Prevention & Control Wuhan 430015 China

Myopia is the leading cause of visual impairments worldwide. Some studies revealed that visual experience in early life affected the final myopia, indicating that environmental factors play an impellent role in the development of myopia. However, risk factors of myopia are still not identified among adolescents in China. A total of 4104 cases of myopia symptom and 3306 emmetropia controls were selected from students in primary and middle schools in Wuhan in 2008. We identified the risk factors associated with myopia symptom by multivariate logistic regression in this cross-sectional study and constructed a risk score system for myopia symptom. The value of the area under the receiver operating characteristic curve (ROC) was 0.735. Furthermore, we followed up 93 students aged 7-9 years for one year and calculated the total points using the score system. We found no significant difference between the final myopia symptom and the results predicted by the total points by pair chi-square test (P>0.05). The score system had a modest ability to estimate the risk factors of myopia symptom. Using this score system, we could identify the students who are at risk of myopia symptom in the future according to their behaviors and environmental factors, and take measures to slow the progress of myopia symptom.

关键词： myopia symptom adolescents risk score system

Rapid and chemoselective imidation of sulfides in aqueous buffer enabled by a novel guanidine-derived N-O reagent

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Science China Chemistry 2024年第6期67卷 1929-1934页

作者： Hanzheng Li long xu Jiajia Dong Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China Institute of Translational Medicine National Facility for Translational Medicine(Shanghai)Shanghai Jiao Tong UniversityShanghai200240China School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai200240China Shanghai Artificial Intelligence Laboratory Shanghai200232China

Herein we report the facile synthesis of a series of novel N-O reagents and identify N′-di-Boc-N′′-[(mesitylsulfonyl)oxy]-guanidine as an efficient imidating *** reagent is synthetically scalable and bench-stable,yet it shows unprecedented reactivity and chemoselectivity towards S(II)in buffer/hexafluoroisopropanol(HFIP)system,to generate a new class of Nguanyl *** transformation of N-guanyl sulfilimines to N-guanyl sulfoximines provides us a chance to investigate these rarely reached compounds,which are shown to be versatile precursors to a variety of N-heterocyclic and *** work provides an addition to the tool box of both sulfur imidation and guanidine synthesis,especially for the need of rapid and selective modifications of sulfur(II)center under biocompatible conditions.

关键词： sulfur imidation N-O reagent

Unconditionally stable Crank-Nicolson algorithm with enhanced absorption for rotationally symmetric multi-scale problems in anisotropic magnetized plasma

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Journal of Systems Engineering and Electronics 2024年第1期35卷 65-73页

作者： wen Yi WANG Junxiang xu Hongbing School of Automatic Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Beijing Institute of Aerospace Systems Engineering Beijing 100076China

Large calculation error can be formed by directly employing the conventional Yee’s grid to curve *** order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is proposed for rotationally symmetric multi-scale problems in anisotropic magnetized *** the CNDG algorithm,an alternative scheme for the simulation of anisotropic plasma is proposed in body-of-revolution *** perfectly matched layer(CPML)formulation is proposed to efficiently solve the open region *** example is carried out for the illustration of effectiveness including the efficiency,resources,and *** the results,it can be concluded that the proposed scheme shows considerable performance during the simulation.

关键词： anisotropic magnetized plasma body-of-revolution(BOR) Crank-Nicolson Douglas-Gunn(CNDG) finite-difference time-domain(FDTD) perfectly matched layer(PML) rotationally symmetric multi-scale problems

Cation-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode with high rate performance

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Chinese Journal of Chemical Engineering 2024年第6期70卷 139-148页

作者： long Zhang Dongsheng Yang Lilei Miao Chunmeng Zhang Jiexiang Li Jiawei wen Chunxia Wang Tiantian Cao Guoyong Huang Shengming xu College of New Energy and Materials China University of PetroleumBeijing 102249China State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China Beijing Spacecrafts Beijing 100094China SINOPEC Sales Co. Ltd.Beijing 100728China SINOPEC Research Institute of Petroleum Processing Co. LtdBeijing 100083China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Beijing Key Laboratary of Fine Ceramics Tsinghua UniversityBeijing 100084China

The nickel-rich layered cathode material LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)has high energy density,lower cost and is a promising cathode material currently under ***,its electrochemical and structural stability is poor during *** the many modification methods,cation doping has been consistently proven to be an effective strategy for enhancing electrochemical ***,the NCM811 cathode material was modified by solid-phase reactions with Mg and Al *** addition,the corresponding mechanism of NCM811 cathode material-doped modification is explored by density functional theory(DFT)calculations,and we have extended this approach to other ternary cathode materials with different ratios and obtained universal *** with DFT calculations,the results show that Mg2+occupies the Li+site and reduces the degree of Li^(+)/Ni^(2+) mixture;Al^(3+) acts as a structural support during charging and discharging to prevent structural *** electrochemical properties were tested by an electrochemical workstation and the LAND system,and the results showed that the capacity retention rate increased to varying degrees from 63.66%to 69.87%and 89.05%for NCM811-Mg and NCM811-Al at room temperature after 300 cycles,*** study provides a theoretical basis and design strategy for commercializing cationic-doped modification of nickel-rich cathode materials.

关键词： Li-ion batteries Cathode materials Doped Electrochemical properties DFT calculation

CdS/LaFeO_(3) heterojunctions with improved optical properties for visible-light catalytic applications

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Journal of Rare Earths 2024年第5期42卷 879-888,I0003页

作者： Jiaqi Wei wen Zhu xuelian xu Xiao xu Junjiang Zhu Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile University ChemistryWuhan430200China

Construction of heterojunctions is a normal and effective strategy to improve the photocatalytic performances of semiconductors,through which both the lifetime and the redox ability of electrons/holes can be improved,as co mpared to the respective *** this basis,we constructed Z-scheme CdS/LaFeO_(3) heterojunctions(CdS/LFO),by in-situ growing different amounts of CdS on the surface of LaFeO_(3),for photocatalytic degradation of tetracycline hydrochloride(TC)in aqueous solution at room *** crystal structure,surface morphology and optoelectronic properties of the COS/LFO heterojunctions were systemically characterized to correlate the reaction *** tests indicate that the CdS/LFO heterojunctions exhibit promising activity for TC degradation under visible light irradiation(λ≥420 nm),with 85%TC conversion obtained at reaction time of 45 min,which is 3.4 and 1.9 times higher than that of CdS and LaFeO_(3).The CdS/LFO heterojunctions are also stable in the reaction and can be reused for four cycles with no appreciable activity *** applicability of CdS/LFO to photocatalytic degradation of organic dyes,as well as the reaction mechanism,was also explored.

关键词： LaFeO_(3) CdS Photocatalytic degradation Tetracycline hydrochloride Reaction mechanism Rare earths