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Chinese Journal of Polymer Science 2013年第10期31卷 1352-1358页

作者： Dan-dan Yuan xu-fu cai Department of Polymer Science and Materials State Key Laboratory of Polymer Materials Engineering Sichuan University

A novel flame retardant （DAPSiO）, containing silicon and nitrogen, was synthesized by using dichlorodiphenylsilane, γchloropropyl methyl dimethoxysilane and 1,2-ethanediamine. DAPSiO was used together with potassium-4-（phenylsulfonyl）benzenesulfonate （KSS） to prepare a flame-retardant system for polycarbonate （PC）. The structure of DAPSiO was characterized by Fourier transform infrared spectroscopy （FTIR）, and 1H-NMR tests. Flammability and thermal behaviors of PC/KSS/DAPSiO systems were estimated by limited oxygen index （LOI）, vertical burning test （UL-94） and thermogravimetric analysis （TGA） tests. The results showed that the flame retardancy and thermal stability of PC/KSS system were improved with the addition of DAPSiO. When 1 wt% DAPSiO and 0.5 wt% KSS were incorporated, the LOI value of PC was found to be 44, and class V-0 of UL-94 test was passed. The scanning electron microscopy （SEM） and FTIR indicated that PC/KSS/DAPSiO system held a more cohesive and denser char structure when compared with pure PC and PC/KSS system.

关键词： Flame retardant Thermal properties Silicon Polycarbonate.

A unified gas-kinetic scheme for multiscale and multicomponent flow transport

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Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 355-372页

作者： Tianbai XIAO Kun xu Qingdong cai Department of Mechanics and Engineering Science College of EngineeringPeking University Department of Mathematics Hong Kong University of Science and Technology Department of Mechanical and Aerospace Engineering Hong Kong University of Science and Technology Shenzhen Research Institute Hong Kong University of Science and Technology

Compressible flows exhibit a diverse set of behaviors, where individual particle transports and their collective dynamics play different roles at different scales. At the same time, the atmosphere is composed of different components that require additional degrees of freedom for representation in computational fluid dynamics. It is challenging to construct an accurate and efficient numerical algorithm to faithfully represent multiscale flow physics across different regimes. In this paper, a unified gas-kinetic scheme(UGKS) is developed to study non-equilibrium multicomponent gaseous flows. Based on the Boltzmann kinetic equation, an analytical space-time evolving solution is used to construct the discretized equations of gas dynamics directly according to cell size and scales of time steps, i.e., the so-called direct modeling method. With the variation in the ratio of the numerical time step to the local particle collision time(or the cell size to the local particle mean free path), the UGKS automatically recovers all scale-dependent flows over the given domain and provides a continuous spectrum of the gas dynamics. The performance of the proposed unified scheme is fully validated through numerical *** UGKS can be a valuable tool to study multiscale and multicomponent flow physics.

关键词： unified gas-kinetic scheme(UGKS) multiscale modeling multicomponent flow

Exergy analysis and performance enhancement of isopropanol-acetone-hydrogen chemical heat pump

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Frontiers in Energy 2017年第4期11卷 510-515页

作者： Min xu Jun cai Xiulan HUAI Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China

Exergy loss analysis was conducted to identify the irreversibility in each component of the isopropanol- acetone-hydrogen chemical heat pump （IAH-CHP）. The results indicate that the highest irreversibility on a system basis occurs in the distillation column. Moreover, the effect of operating parameters on thermodynamic performances of the IAH-CHP was studied and the optimal conditions were obtained. Finally, the potential methods to reduce the irreversibility of the IAH-CHP system were investigated. It is found that reactive distillation is apromising alternative. The enthalpy and exergy efficiency of the IAH-CHP with reactive distillation increases by 24.1% and 23.2%, respectively.

关键词： waste heat reuse chemical heat pump exergyanalysis isopropanol

Effect of^3B Group in Rings on Special Dispersion of B2O3-SiO2-ZrO2-Ta2O5-Na2O System Glass

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Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1032-1038页

作者： xu Xiaodian WANG Yanhang zu Chengkui ZHOU Peng China Building Materials Academy Beijing 100024China

Borosilicate glasses,with x B2O3-（60-x）SiO2-8ZrO2-8Ta2O5-24Na2O（7≤x≤59 mol%）composition,were fabricated by melt-quenching ***,UV-Vis,Raman and IR spectroscopic studies were utilized to investigate the structure of fabricated *** NMR spectrum was deconvoluted into five Gaussian bands,assigned to ^4B（0B,4Si）,^4B（1B,3Si）,^4B（2B,2Si）,^3B（rings）and ^3B（loose）,to get their quantitative *** relative dispersion deviation？P（g,F） was attributed to the relative quantity of ^3B（rings）but not all ^3B groups,and B2O3 existed mainly as[BO3]in rings firstly,and then as[BO3]in loose *** UV-Vis spectra revealed that the quantity of non-bridging oxygen increased firstly and then decreased with increasing concentration of *** as complementary techniques,Raman and IR measurements revealed that four-coordinated boron and silica mainly existed as ^4B-O-B,and Si-O-Si in Q^2,respectively,as chain structure but not framework structure,and[B？4]units prefered connections with borate rather than with silicate entities of the glass network in these studied *** addition,the conclusion also certified that ^3B in＂loose＂condition located in lower wavenumbers between 1 200-1 600 cm^-1 in Raman spectra.

关键词： borosilicate glass structure NMR Raman relative dispersion deviation

Tribological properties of high velocity arc sprayed Fe-Al based composite coatings at elevated temperature

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 379-382页

作者： ZHANG Wei ZHANG Shu xu Wei-pu zu Zi-xin xu Bin-shi National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

Fe-Al based intermetallic composite coatings were in-situ synthesized using Fe-Al/Cr3C2 or Fe-Al/WC cored wires and high velocity are spraying (HVAS) technology. The tribological properties of the Fe-Al based intermetallic composite coatings were investigated using a ball-on-disc tribotester from room temperature to 650 ℃. The results show that the coatings have relatively high bond strength and micro-hardness. The tribological properties of Fe-Al/Cr3C2 and Fe-Al/WC composite coatings were further analyzed and compared. Low and stable wear rates of the Fe-Al based intermetallic composite coatings were indicated from room temperature to 650 ℃. The excellent wear resistance of the composite coatings in high temperature was discussed.

关键词： high velocity arc spray (HVAS) composite coating tribology

An adaptive loop gain selection for CLEAN deconvolution algorithm

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Research in Astronomy and Astrophysics 2019年第6期19卷 37-42页

作者： Li Zhang Long xu Ming Zhang Zhong-zu Wu College of Big Data and Information Engineering Guizhou University Guiyang 550025 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China Key Laboratory of Radio Astronomy Chinese Academy of Sciences Urumqi 830011 China College of Physics Guizhou University Guiyang 550025 China

Radio interferometry significantly improves the resolution of observed images, and the final result also relies heavily on data recovery. The Cotton-Schwab CLEAN(CS-Clean) deconvolution approach is a widely used reconstruction algorithm in the field of radio synthesis imaging. However, parameter tuning for this algorithm has always been a difficult task. Here, its performance is improved by considering some internal characteristics of the data. From a mathematical point of view, a peak signal-to-noise-based(PSNRbased) method was introduced to optimize the step length of the steepest descent method in the recovery process. We also found that the loop gain curve in the new algorithm is a good indicator of parameter *** show that the new algorithm can effectively solve the problem of oscillation for a large fixed loop gain and provides a more robust recovery.

关键词： methods data analysis-techniques image processing-techniques interferometric

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang Wei Kang Zhou Xin Huang Xing Zhou Jie xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （<0.7 V） and excellent cyclic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

Switchable 2,3-dithienylmaleimide bonded to different fluorophores: synthesis and photochromic properties

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1590-1594页

作者： Lei xu zu-jin ZHAO Ya-jun XING Ping LU Department of Chemistry Zhejiang University Hangzhou 310027 China

A series of photochromic diarylethene derivatives containing different fluorophores was synthesized by the Sonogashira coupling reaction and characterized by 1H nuclear magnetic resonance (NMR), 13C NMR and mass spectroscopy. Photochromic conversion of Cz-MS was observed and its structural change was confirmed by proton NMR. Switchable absorption and emission phenomena were observed for these molecules. These phenomena were attributed to the reversible photochromic fluorescence resonance energy transfer (pcFRET) process. The design of this novel photochromic system of Py-4MS enables information to be processed in a non-destructive manner. This overcomes the problem of the destructive nature of tracking photochromism using ultraviolet (UV)-vis spectroscopy.

关键词： Photochromic reaction Diarylethene derivatives Photochromic fluorescence resonance energy transfer (pcFRET)

NUMERICAL MODELING OF WASTEWATER TRANSPORT AND DEGRADATION IN SOIL AQUIFER

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Journal of Hydrodynamics 2006年第5期18卷 597-605页

作者： YIN Hai-long xu zu-xin LI Huai-zheng LI Song College of Environmental Science and Engineering Yongji University Shanghai 200092 China Shanghai Academy of Environment Sciences Shanghai 200233 China College of Environmental Science and Engineering Tongii University Shanghai 200092 China

Modeling of wastewater transport and degradation in soil aquifer is a problem of concern with regard to the optimization of design and operation of the wastewater soil treatment system. To solve this problem, three-dimensional groundwater flow and wastewater transport and degradation model was developed using MODFLOW and MT3DMS modeling. The developed model was calibrated using the Soil Infiltration Treatment System （SITS） in the Chongming island of China after considering the river-groundwater interaction and the regional geological and hydrological conditions. Using the calibrated model, the following problems with regard to the design and operation of SITS were discussed：（1） Allowable hydraulic load. The hydraulic load increases with the drop in the water level of the adjoining river, the increase in the actual soil area under operation, and the increase in the distance among the individual operation units of SITS. （2） Optimized layout of the groundwater monitoring wells. The concentration contour of the simulated contaminants is very useful to depict the typical areas that are most severely polluted and very sensitive to the peripheral environment,, thus lesser number of monitoring wells can be set up based on the model, and the goal of the accurate assessment of the influence of soil-infiltrated wastewater on groundwater can be achieved.

关键词： groundwater model wastewater soil aquifer hydraulic load

Study on liquid-filled structure target with shaped charge vertical penetration

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Defence Technology（防务技术） 2019年第6期15卷 861-867页

作者： Min Guo xu-dong zu Xiao-jun Shen Zheng-xiang Huang School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing 210094China Unit 63961 Peoples Liberation Army6th Beiyuan RoadChaoyang Beijing100012China

Based on the characteristic expanded hole of a shaped charge jet(SCJ) for target penetration and the reflow characteristics of liquids,the liquid-filled structure of a target disturbs the stability of the SCJ acquired in two independent *** interference jet speed interval,the escape jet speed interval,and the surplus depth are calculated on the basis of the virtual origin *** experimental results,including the velocity of the escaped jet tip and the surplus depth of penetration,are consistent with the theoretical *** show that the theory can describe the interaction process of the target with a shaped charge jet.

关键词： Shaped charge Liquid-filled structure target Disturbed jet Escape jet