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Effect of dielectric material on the uniformity of nanosecond pulsed dielectric barrier discharge

Plasma Science and Technology 2024年第9期26卷 79-87页

作者： Wenhao ZHOU Dongxuan ZHANG Xiaohui duan Xi ZHU Feng LIU Zhi fang College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816People’s Republic of China

Dielectric barrier discharge(DBD)is considered as a promising technique to produce large volume uniform plasma at atmospheric pressure,and the dielectric barrier layer between the electrodes plays a key role in the DBD processes and enhancing discharge *** this work,the uniformity and discharge characteristics of the nanosecond(ns)pulsed DBD with dielectric barrier layers made of alumina,quartz glass,polycarbonate(PC),and polypropylene(PP)are investigated via discharge image observation,voltage-current waveform measurement and optical emission spectral *** analyzing discharge image by gray value standard deviation method,the discharge uniformity is quantitatively *** effects of the space electric field intensity,the electron density(Ne),and the space reactive species on the uniformity are studied with quantifying the gap voltage Ug and the discharge current Ig,analyzing the recorded optical emission spectra,and simulating the temporal distribution of Ne with a one-dimensional fluid *** is found that as the relative permittivity of the dielectric materials increases,the space electric field intensity is enhanced,which results in a higher Ne and electron temperature(Te).Therefore,an appropriate value of space electric field intensity can promote electron avalanches,resulting in uniform and stable plasma by the merging of electron ***,an excessive value of space electric field intensity leads to the aggregation of space charges and the distortion of the space electric field,which reduce the discharge *** surface roughness and the surface charge decay are measured to explain the influences of the surface properties and the second electron emission on the discharge *** results in this work give a comprehensive understanding of the effect of the dielectric materials on the DBD uniformity,and contribute to the selection of dielectric materials for DBD reactor and the realization of atmospheric pre

关键词： dielectric barrier discharge dielectric material uniformity discharge characteristics

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Robust tantalum tuned perovskite oxygen electrode for reversible protonic ceramic electrochemical cells

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Rare Metals 2024年第7期43卷 3055-3065页

作者： Yu-Shi Feng Yu Shen fang Wang Chuan Tian Qin-Yi Hu Qian duan Jing-Wei Li Di Bao School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China Zhongshan Institute of Changchun University of Science and Technology Zhongshan528437China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022China Key Laboratory of Preparation and Applications of Environmental Friendly Materials Ministry of EducationJilin Normal UniversityChangchun 130103China

Perovskite oxides with diverse composition and structure have exhibited grand advances in boosting the oxygen reduction and evolution reaction(ORR/OER),which are essential for the reversible protonic ceramic electrochemical cell(R-PCEC)toward the sustainable hydrogen production and ***,enhancement of their activity and stability remains ***,we develop the Ta-regulated BaCo_(0.7)Fe_(0.3)O_(3-δ)perovskite oxygen electrode(Ba(Co_(0.7)Fe_(0.3))_(1-x)Ta_xO_(3-δ))with abundant oxygen defects and achieve the simultaneous enhancement in the electrocatalytic activity and stability toward ORR and ***-fabricated R-PCEC with(Ba(Co_(0.7)Fe_(0.3))_(0.9)Ta_(0.1)O_(3-δ))(BCFT10)oxygen electrode performs high power density of 1.47 W·cm^(-2)at 650℃in fuel cell mode,and the current density is up to-2.11 A·cm^(-2)at 1.4 V at 650℃in electrolysis mode,as well as the good stability in both the fuel cell and electrolysis ***,the cell also demonstrates a stable cycling operation between fuel cell and electrolysis mode,suggesting a great potential of BCFT10 as oxygen electrode material for R-PCECs.

关键词： Reversible protonic ceramic electrochemical cells Perovskite oxide Oxygen electrode Ta element doping Oxygen defects

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氧化石墨烯褶皱行为与结构的分子模拟研究

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物理学报 2020年第19期69卷 66-73页

作者：陈超段芳莉重庆大学机械传动国家重点实验室重庆400030

应用反应力场分子动力学方法,模拟了单层氧化石墨烯在径向压缩作用下的褶皱过程,研究了含氧基团(羟基、环氧基)对氧化石墨烯褶皱行为以及褶皱球结构稳定性的影响.当石墨烯仅含羟基时,该类氧化石墨烯呈现出“推进式”的褶皱行为,而当石... 详细信息

应用反应力场分子动力学方法,模拟了单层氧化石墨烯在径向压缩作用下的褶皱过程,研究了含氧基团(羟基、环氧基)对氧化石墨烯褶皱行为以及褶皱球结构稳定性的影响.当石墨烯仅含羟基时,该类氧化石墨烯呈现出“推进式”的褶皱行为,而当石墨烯仅含环氧基时,该类氧化石墨烯则呈现出片层与片层“贴合式”的褶皱行为.褶皱行为的不同决定了氧化石墨烯最终褶皱球结构的差异.通过分析原子级势能增量分布与C—C成、断键位置之间的关系,发现氧化石墨烯上C—C成、断键主要发生在变形较为严重的区域,且相较于羟基,环氧基对与其连接的C—C键具有更强的削弱作用.为了研究氧化石墨烯褶皱球的结构稳定性,模拟了其在无约束条件下的释放过程.发现氧化石墨烯褶皱球的结构稳定性取决于其中C—C成、断键数量,即C—C成、断键的数量越多,结构越稳定,且在同一氧化率下,褶皱球的结构稳定性随环氧基比例的增大而提高.本研究表明,通过改变氧化石墨烯片层上含氧基团的相对比例,可实现对其褶皱球稳定性的控制.

关键词：氧化石墨烯褶皱行为稳定性分子动力学模拟

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单个纳米粒子对聚合物结晶行为的影响

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物理学报 2014年第13期63卷 282-289页

作者：段芳莉王源重庆大学机械传动国家重点实验室重庆400030

采用粗粒化模型,应用分子动力学方法研究了单个纳米粒子对聚合物结晶行为的影响.通过改变纳米粒子与聚合物单体之间作用方式(吸引作用或排斥作用)、纳米粒子与聚合物单体之间作用强度和聚合物分子链的长度,计算整个系统和局部区域的有... 详细信息

采用粗粒化模型,应用分子动力学方法研究了单个纳米粒子对聚合物结晶行为的影响.通过改变纳米粒子与聚合物单体之间作用方式(吸引作用或排斥作用)、纳米粒子与聚合物单体之间作用强度和聚合物分子链的长度,计算整个系统和局部区域的有序参数,研究了三个不同因素下纳米粒子对聚合物结晶行为的不同影响.研究表明,在聚合物基体中添加单个纳米粒子,纳米粒子对整个系统的结晶影响不明显,但是纳米粒子对其周围聚合物单体的结晶存在局部强化作用.当纳米粒子与聚合物单体之间为吸引作用且作用强度较大时,纳米粒子对聚合物结晶表现出明显的局部强化作用,聚合物分子链长度也有着一定的影响,在较大吸引作用强度下,长链样本比短链样本有着更为显著的局部强化作用.

关键词：纳米粒子聚合物系统半晶态结晶行为分子动力学模拟

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界面氢键对受限水结构和动态特性的影响

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物理学报 2015年第21期64卷 432-439页

作者：王明段芳莉重庆大学机械传动国家重点实验室重庆400030

应用反应力场分子动力学方法,模拟了水限制在全羟基化二氧化硅晶体表面间的弛豫过程,研究了基底表面与水形成的界面氢键,及其对受限水结构和动态特性行为的影响.当基底表面硅醇固定时,靠近基底表面水分子中的氧原子与基底表面的氢原子... 详细信息

应用反应力场分子动力学方法,模拟了水限制在全羟基化二氧化硅晶体表面间的弛豫过程,研究了基底表面与水形成的界面氢键,及其对受限水结构和动态特性行为的影响.当基底表面硅醇固定时,靠近基底表面水分子中的氧原子与基底表面的氢原子形成强氢键,这使得靠近表面水分子中的氧原子比对应的氢原子更靠近基底表面,从而水分子的偶极矩远离表面.当基底表面硅醇可动时,靠近基底表面水分子与基底表面原子形成两种强氢键,一种是水分子中的氧原子与表面的氢原子形成的强氢键,数量较少,另一种是水分子中的氢原子与表面的氧原子形成的强氢键,数量较多,这使得靠近表面水分子中的氢原子比对应的氧原子更靠近表面,从而水分子的偶极矩指向表面.在相同几何间距下,当基底表面硅醇可动时,表面的活动性使得几何限制作用减弱,导致了受限水分层现象没有固定表面限制下的明显.此外,固定表面比可动表面与水形成的界面氢键作用较强,数量较多,导致了可动表面限制下水的运动更为剧烈.

关键词：受限水界面氢键二氧化硅晶体分子动力学模拟

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组蛋白去乙酰化酶的结构及应用

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生物化学与生物物理进展 2015年第11期42卷 978-993页

作者：曹端方杨娜中国科学院生物物理研究所生物大分子国家重点实验室北京100101

组蛋白赖氨酸乙酰化是目前研究最为广泛和深入的组蛋白翻译后修饰之一,在染色质重塑和基因表达调控等方面发挥重要作用,这种修饰在体内受到组蛋白乙酰化酶和去乙酰化酶的高度动态调控.除了以组蛋白为底物外,组蛋白去乙酰化酶还可以催化... 详细信息

组蛋白赖氨酸乙酰化是目前研究最为广泛和深入的组蛋白翻译后修饰之一,在染色质重塑和基因表达调控等方面发挥重要作用,这种修饰在体内受到组蛋白乙酰化酶和去乙酰化酶的高度动态调控.除了以组蛋白为底物外,组蛋白去乙酰化酶还可以催化多种非组蛋白的去乙酰化,参与多种生命过程的调节.本文围绕四类人源组蛋白去乙酰化酶,综述了其分类依据、结构与功能特点、催化反应的分子机制,以及针对这些组蛋白去乙酰化酶的抑制剂和激动剂的开发和应用等方面的研究进展.

关键词：组蛋白乙酰化修饰组蛋白去乙酰化酶 Sirtuin 结构与功能催化机制抑制剂激动剂

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Onychin inhibits proliferation of vascular smooth muscle cells by regulating cell cycle

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Acta Pharmacologica Sinica 2005年第2期26卷 205-211页

作者： Ming YANG~2,Hong-lin HUANG~2,Bing-yang ZHU,Qin-hui TUO,duan-fang LIAO~3Institute of Pharmacy and Pharmacology,Nanhua University,Hengyang 421001,China InstituteofPharmacyandPharmacology NanhuaUniversityHengyang421001China

Aim:To investigate the effects of onychin on the proliferation of cultured ratartery vascular smooth muscle cells(VSMCs)in the presence of 10% new-borncalf serum(NCS).Methods:Rat VSMCs were incubated with onychin 1-50μmol/L or genistein 10μmol/L in the presence of 10% NCS for 24 *** prolif-eration of VSMCs was measured by cell counting and MTS/PMS *** cycle progression was evaluated by flow ***(Rb)phosphorylation,and expression of cyclin D1and cyclin E were measured byWestern blot *** tyrosine phosphorylation of ERK1/2 was examined byimmunoprecipitation techniques using anti-phospho-tyrosine ***:The proliferation of VSMCs was accelerated significantly in the presence of 10%*** reduced the metabolic rate of MTS and the cell number of VSMCsin the presence of 10% NCS in a dose-dependent *** cytometry analy-sis revealed that the G1-phase fraction ratio in the onychin group was higher thanthat in the 10% NCS group(85.2% vs 70.0%,P<0.01),while the S-phase fractionratio in the onychin group was lower than that in 10% NCS group(4.3% vs16.4%,P<0.01).Western blot analysis showed that onychin inhibited Rb phos-phorylation and reduced the expression of cyclin D1and cyclin *** effects ofonychin on proliferation,the cell cycle and the expression of cyclins in VSMCswere similar to those of genistein,an inhibitor of tyrosine *** studies showed that both onychin and genistein markedlyinhibited the tyrosine phosphorylation of ERK1/2 induced by 10% ***:Onychin inhibits the proliferation of VSMCs through G1phase cellcycle arrest by decreasing the tyrosine phosphorylation of ERK1/2,and the ex-pression of cyclin D1and cyclin E,and sequentially inhibiting Rb phosphorylation.

关键词： onych(?)n vascular smooth muscle cell cycle retinoblastoma cyclin D1 cyclin E tyrosine kinase mitogen-activated protein kmase

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Effect of heat-activated nickel-titanium arch wire for orthodontic treatment on local tissue inflammation and bone destruction

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Journal of Hainan Medical University 2018年第6期24卷 81-84页

作者： Yan-fang duan Min-Jie Fan Department of Stomatology Hancheng People's Hospital in Shaanxi ProvinceHanchengShaanxi Province715400 Department of Ophthalmology&Otorhinolaryngology Hancheng People's Hospital in Shaanxi ProvinceHanchengShaanxi Province715400

Objective:To study the effect of heat-activated nickel-titanium arch wire for orthodontic treatment on local tissue inflammation and bone ***:Patients who received orthodontic treatment with nickel-titanium arch wire in Hancheng People's Hospital between March 2012 and October 2017 were retrospectively studied, and according to the nickel-titanium arch wire materials in history data, the patients were divided into the experimental group who used heat-activated nickel-titanium arch wire and the control group who used common nickel-titanium arch wire. 1 week after treatment, the gingival crevicular fluid was collected to determine the contents of inflammatory cytokines as well as the mRNA expression of osteoblast markers and osteoclast ***: 1 week after treatment, IL-1α, IL-1β, sTREM1 and HMGB1 contents as well as RANKL, 5-LOX, LTB4, TRACP5b and ODF mRNA expression in gingival crevicular fluid of experimental group were significantly lower than those of control group whereas OPG, Wnt3a, Runx2, OC, ALP and OCIF mRNA expression were significantly higher than those of control ***: Heat-activated nickel-titanium arch wire for orthodontic treatment can be more effective than common nickel-titanium arch wire to reduce the local tissue inflammation and inhibit the bone destruction.

关键词： Orthodontic treatment Heat-activated nickel-titanium arch wire Inflammation Bone destruction Apoptosis

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A NEW FINITE VOLUME METHOD FOR SOLVING SHALLOW WATER EQUATIONS

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Journal of Hydrodynamics 1993年第2期5卷 13-18页

作者： Zhang Ting-fang duan Xiao ning Dalian University of Technology,Dalian 116024,P.R.China

This paper presents a new numerical model using the finite volume method with arbitrary polygonal elements,It is suitable for simulating the shallow water problem with com- plex topography and boundary *** calculated results show that this kind of method has the advantages of good stability,convenience of solving,easy programming,less,computing time and storage,high accuracy,ect.

关键词： shallow water equation numerical simulation finite volume method

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Effect of Humidity on Formaldehyde Oxidation over Ce_(0.8)Zr_(0.2)O_(y)Catalyst

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1108-1115页

作者： TANG Ruijiu YANG Zonglin LIU Xiang JIA Lijuan WANG fang duan Kaijiao LIU Tiancheng College of Chemistry and Environment Yunnan Minzu UniversityTechnology Innovation Team of Green Purification Technology for Industrial Waste GasEducation Department of YunnanKey Laboratory of Environmental Functional Materials of Yunnan Province Education DepartmentKunming 650504China

In the preparation of a series of Ce_(0.8)Zr_(0.2)O_(y)catalysts catalyzing the removal of formaldehyde,BET,H2-TPR,IR,SEM,XPS,and XRD were used to characterize the catalyst,and the influence of humidity on the catalyst activity was studied by adjusting the humidity during the *** experimental results showed that the formaldehyde removal rate increased with the increase of *** the humidity was higher than 50%,the formaldehyde removal rate decreased by 3%over that when the humidity was 50%.The characterization results showed that humidity facilitated the activation of oxygen and the formation of hydroxyl groups,which both promoted the formation and oxidative decomposition of intermediates and prevented the deposition of intermediates that clogged the pores,allowing more formaldehyde to be adsorbed and oxidized,which increased the activity of the *** provides new mechanistic evidence for the oxidation of formaldehyde and helps in the development of relatively low-cost materials for formaldehyde purification.

关键词： formaldehyde humidity Ce_(0.8)Zr_(0.2)O_(y) catalytic oxidation

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