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Chinese Journal of Chemical Engineering 2018年第7期26卷 1522-1527页

作者： zhijun yan Xiangcun Li Xiaobin Jiang Le Zhang yan Dai Gaohong He State Key Laboratory of Fine Chemicals Chemical Engineering Department Dalian University of Technology

In this work, SiO2 nanoplates with opened macroporous structure on carbon layer （C-mSiO2） have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell hollow spheres. Subsequently, triple-shell C-mSiO2-C hollow spheres were successfully prepared after coating the C- mSiO2 templates by the carbon layer from the carbonization of sucrose. When being applied as the anode material fur lithium-ion batteries, the C-mSiO2-C triple-shell hollow spheres deliver a high capacity of 501 mA. h.g- 1 after 100 cycles at 500 mA.g-1 （based on the total mass of silica and the two carbon shells）, which is higher than those of C-mSiO2 （391 mA.h.g 1） spheres with an outer porous SiO2 layer, C-SiO2-C （370 mA-h.g-1） hollow spheres with a middle solid Si02 layer, and C-SiO2 （319.8 mA·h-g-1） spheres with an outer solid SiO2 layer. In addition, the battery still delivers a high capacity of 403 mA· h· g- 1 at a current density of 1000 mA· g- 1 after 400 cycles. The good electrochemical performance can be attributed to the high surface area （246.7 m2·g- 1 ） and pore volume （0.441 cm3· g-1） of the anode materials, as well as the unique structure of the outer and inner carbon layer which not only enhances electrical conductivity, structural stability, but buffers volume change of the intermediate SiO2 layer during repeated charge-discharge processes. Furthermore, the SiO2 nanoplates with opened macroporous structure facilitate the electrolyte transport and electrochemical reaction.

关键词： Silica nanoplates Carbon shell Macroporous Lithium-ion battery

The Effect of Martian Ionospheric Dispersion on SAR Imaging

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Space(Science & Technology) 2022年第1期2022卷 409-421页

作者： Bo Wang Xijin Luo Qinghong Sheng zhijun yan Nanjing University of Aeronautics and Astronautics NanjingChina

When passing through the ionosphere,the high-frequency(HF)pulse signal of the Mars Exploration Radar is affected by the dispersion effect error,which results in signal attenuation and time delay and brings about a phase advance in such a way that the echo cannot be matched and *** this paper,a high-order phase model is built to overcome the above problems and enable echo matching and *** studies on the dispersion effect approximate the additional phase after the effect,assuming that the ionosphere is a thin-layer *** this paper,an effective model for the HF waveband is constructed to analyze the change of signal propagation paths in the *** additional phase is expanded in a Taylor series and retained these expansions as high-order terms to calculate the cumulative additional phase along the *** show the rangeoffset variables of signal frequency,bandwidth,and electron density,simulate the effects of the ionosphere under different conditions,and conclude that the model can effectively estimate Mars without considering the effects of magnetic fields and anomalous solar activity and the effect of the ionosphere on synthetic aperture radar(SAR)*** results obtained using ray tracing calculations are different from those obtained by simplifying assumptions,and we can simulate the Martian ionospheric effects by the former.

关键词： effect dispersion Dispersion

UV-Inscribed Optical Fiber Gratings in Mid-IR Range and Their Laser Applications

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Journal of Electronic Science and Technology 2015年第4期13卷 328-342页

作者： Zhongyuan Sun zhijun yan Kaiming Zhou Qizhen Sun Abdulyezir Ayomipo Badmos Lin Zhang Aston Institute of Photonic Technologies Aston University

We have UV-inscribed fiber Bragg gratings （FBGs）, long-period gratings （LPGs） and tilted fiber gratings （TFGs） into mid-IR 2μm range using three common optical fiber grating fabrication techniques （two-beam holographic, phase mask and point-by-point）. The fabricated FBGs have been evaluated for thermal and strain response. It has been revealed that the FBG devices with responses in mid-IR range are much more sensitive to temperature than that in near-IR range. To explore the unique cladding mode coupling function, we have investigated the thermal and refractive index sensitivities of LPGs and identified that the coupled cladding modes in mid-IR range are also much more sensitive to temperature and surrounding medium refractive index change. The 45° tilted fiber gratings （45°-TFGs） as polarizing devices in mid-IR have been investigated for their polarization extinction characteristics. As efficient reflection filters and in-cavity polarizers, the mid-IR FBGs and 45°-TFGs have been employed in fiber laser cavity to realize multi-wavelength 2μm Tm-doped CW and mode locked fiber lasers, respectively.

关键词： Fiber Bragg grating long periodgrating Mid-IR fiber lasers tilted fiber grating.

Time-slot multiplexing based bandwidth enhancement for fiber distributed acoustic sensing

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Science China(Information Sciences) 2022年第1期65卷 292-293页

作者： Hao LI Cunzheng FAN Tao LIU Yujia LIU zhijun yan Perry SHUM Qizhen SUN National Engineering Laboratory for Next Generation Internet Access System Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Sicence and Technology Department of Electrical and Electronic Engineering Southern University of Science and Technology

Dear editor,The phase-sensitive optical time-domain reflectometry(φ-OTDR) has been demonstrated as the most common technique in fiber distributed acoustic sensing(DAS). However,traditional φ-OTDR based DAS suffered from the inherent trade-off between the maximum frequency response and the distance which can be characterized by distance bandwidth product(DBP), since the time interval of the probe pulses should be larger than the pulse round-trip flight time.

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Wearable Alignment‑Free Microfber‑Based Sensor Chip for Precise Vital Signs Monitoring and Cardiovascular Assessment

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Advanced Fiber Materials 2022年第3期4卷 475-486页

作者： Liangye Li Yunfei Liu Changying Song Shunfeng Sheng Liuyang yang zhijun yan Dora Juan Juan Hu Qizhen Sun School of Optical and Electronic Information and National Engineering Laboratory for Next Generation Internet Access System(NGIA)and Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan 430074HubeiChina Institute for Infocomm Research Singapore 138632Singapore

Continuous pulse wave signals monitoring is the essential basis for clinical cardiovascular diagnosis and *** researches show the majority of current electronic pulse sensors usually face challenges in electrical safety concern,poor durability and demanding precision in position ***,a highly sensitive,inherently electrical safe,robust and alignment-free device is highly ***,we present a wearable alignment-free microfber-based sensor chip(AFMSC)for precise vital signs monitoring and cardiovascular health *** AFMSC comprises an optical micro/nano fber sensor(MNF)and a fexible soft liquid sac while the MNF sensor is used to perceive the physiological signals and the liquid sac is used to eliminate the *** real-time and accurate monitoring of the pulse signals was realized by tracking the optical power variation of transmitted light from ***,the cardiovascular vital signs extracted from radial artery pulse signals were used to evaluate cardiovascular health condition and the results were in accordance with human physiological ***,the pulse signals from diferent arterial area,the respiration signals from chest and the radial pulse signals before and after exercise were detected and *** non-invasive,continuous and accurate monitoring of cardiovascular health based on the reported wearable and alignment-free device is promising in both ftness monitoring and medical diagnostics for cardiovascular disease prevention and diagnosis.

关键词： Optical microfber sensor Wearable,alignment-free Physiological signal Cardiovascular health

Health monitoring by optical fiber sensing technology for rechargeable batteries

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eScience 2024年第1期4卷 79-95页

作者： Yi Zhang yanpeng Li Zezhou Guo Jianbo Li Xiaoyu Ge Qizhen Sun zhijun yan Zhen Li Yunhui Huang State Key Laboratory of Material Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanHubei430074China School of Optical and Electronic Information National Engineering Laboratory for Next Generation Internet Access SystemWuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhanHubei430074China Henan Key Laboratory of Laser and Opto-electric Information Technology School of Electrical and Information EngineeringZhengzhou UniversityZhengzhouHenan45001China

With the proposal of a“smart battery,”real-time sensing by rechargeable batteries has become progressively more important in both fundamental research and practical ***,many traditional sensing technologies suffer from low sensitivity,large size,and electromagnetic interference problems,rendering them unusable in the harsh and complicated electrochemical environments of *** optical sensor is an alternative approach to realize multiple-parameter,multiple-point measurements ***,it has garnered significant *** analyzing these measured parameters,the state of interest can be decoded to monitor a battery's *** review summarizes current progress in optical sensing techniques for batteries with respect to various sensing parameters,discussing the current limitations of optical fiber sensors as well as directions for their future development.

关键词： Optical fiber sensing Rechargeable battery Real-time sensing Health monitoring

Screen, Design and Enzymatic Activity Determination of Artificial Microperoxidases

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Chemical Research in Chinese Universities 2018年第6期34卷 934-938页

作者： XU Jia ZHAO Xiaoming YUAN Ye SONG yanhui WANG Jiaqi WANG Chonghan CHEN Yujia WANG Jianing yan zhijun GUAN Shuwen WANG Liping School of Life Sciences Jilin University Changchun 130012 P. R. China Scientific Research Center China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

Peroxidase activity greatly impacts the maintenance of flee radical homeostasis, and can prevent or treat diseases related to free radicals. Microperoxidase-11（MP-11 ） is created via hydrolysis of cytochrome c iron-porphyrin complexes. In these complexes, the heme iron is penta-coordinate with histidine and exhibits excellent antioxidant activity when decomposing hydrogen peroxide. In this study, we screened the Ph.D.-7 and Ph.D.-12 phage display＇ peptide libraries and obtained ten small peptide ligands of deuterohemin（the vinyl groups of oxidized heme）. Among these polypeptides, DhHP-7P1, 12P1, 12P2 and 12P6 have good enzymatic activity compared with MP-11, and exhibit activities up to 50% of MP-11. Based on the screened sequences, we designed a series of artificial microperoxidases and determined that a higher peroxidase activity could be achieved with an enzymatic active site containing a second site of histidine residue spaced between two arginine residues with an interval of two amino acids（Dh-XHRXXR）.

关键词： Microperoxidase- 11 Deuterohemin Artificial microperoxidase Enzymatic activity

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公众参与下的企业能源消费行为演化研究

系统工程理论与实践 2016年第10期36卷 2537-2548页

作者：曲卫华颜志军北京理工大学管理与经济学院北京100081 太原学院计算中心太原030032 北京理工大学能源与环境政策研究中心北京100081

企业能源消费导致的环境污染严重影响公众的公共健康水平,阻碍生态文明的可持续发展.运用演化博弈理论与方法,围绕公共健康损失赔偿大小,研究了公众与高污染企业能源消费行为策略选择的互动机制;运用数值实验建立了公共健康损失赔偿较... 详细信息

企业能源消费导致的环境污染严重影响公众的公共健康水平,阻碍生态文明的可持续发展.运用演化博弈理论与方法,围绕公共健康损失赔偿大小,研究了公众与高污染企业能源消费行为策略选择的互动机制;运用数值实验建立了公共健康损失赔偿较小、公共健康损失赔偿较大以及公共健康损失与企业额外收益均较大三种博弈场景,展示了决策参数的不同取值和初始状态改变对演化结果的影响.研究表明:在不同场景下,公众参与下的企业能源消费行为演化路径的速度与策略均有差异.公众与高污染企业的策略主要由公众健康损失赔偿、企业转型成本及额外收益共同决定;公共健康损失赔偿较大、污染企业实行能源转型策略比例达到95%以上与企业额外收益足够大时,公众与污染企业最终分别演化为不参与环境管理和实行能源转型策略.本文的研究结果可为公共健康水平的提升提供相应的参考.

关键词：演化博弈能源消费环境污染公共健康

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Cu／Ni多层膜强化机理的分子动力学模拟

金属学报 2008年第12期44卷 1461-1464页

作者：程东严志军严立大连海事大学轮机工程学院大连116026 大连海事大学金属工艺研究所大连116026

运用分子动力学方法模拟了Cu/Ni薄膜结构在纳米压入和微摩擦过程位错的运动规律,探讨了薄膜结构中位错与界面的相互作用规律.结果表明:Cu/Ni多层膜结构中的层间界面会阻碍位错继续向材料内部扩展,阻碍作用主要来自于两个方面:界面失配... 详细信息

运用分子动力学方法模拟了Cu/Ni薄膜结构在纳米压入和微摩擦过程位错的运动规律,探讨了薄膜结构中位错与界面的相互作用规律.结果表明:Cu/Ni多层膜结构中的层间界面会阻碍位错继续向材料内部扩展,阻碍作用主要来自于两个方面:界面失配位错网对位错运动的排斥阻力使其难以到达或穿过界面;由弹性模量差而产生的界面镜像力使位错被限制在Cu单层膜内运动.这种阻碍作用有利于提高Cu/Ni多层薄膜的力学性能.

关键词： Cu/Ni多层膜分子动力学模拟失配位错镜像力

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单晶Cu表面黏-滑效应的分子动力学模拟

金属学报 2006年第11期42卷 1149-1152页

作者：程东严志军严立大连海事大学轮机工程学院大连116026 大连海事大学金属工艺研究所大连116026

运用分子动力学方法模拟了Cu单晶在微摩擦过程中的黏-滑效应．模拟结果表明:在原子尺度,摩擦表面的原子排列较规则,摩擦力曲线为大小锯齿的周期变化．这种黏-滑效应可以解释为位错机制,即摩擦表面间位错的产生与消失的过程．大小锯齿的... 详细信息

运用分子动力学方法模拟了Cu单晶在微摩擦过程中的黏-滑效应．模拟结果表明:在原子尺度,摩擦表面的原子排列较规则,摩擦力曲线为大小锯齿的周期变化．这种黏-滑效应可以解释为位错机制,即摩擦表面间位错的产生与消失的过程．大小锯齿的峰值受载荷、滑动速度、接触面两侧的晶格常数及品格位向差等多个因素的影响．载荷越大,针尖滑动时移动的原子数量越多,接触面两侧的原子排列越不规则,则小锯齿的峰值越小,并随着载荷的增大而逐渐消失．摩擦力曲线中的小锯齿峰值与滑动速度呈线性关系．不同材料的接触面和不同滑动方向的黏-滑现象并不相同．摩擦力曲线的变化周期取决于滑动过程中基体沿滑动方向的晶格常数．

关键词： Cu单晶黏-滑效应分子动力学模拟微观干摩擦