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New method for controlling minimum length scales of real and void phase materials in topology optimization

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Acta Mechanica Sinica 2020年第4期36卷 805-826页

作者： Xuanpei rong jianhua rong Shengning Zhao Fangyi Li Jijun Yi Luo Peng School of Automotive and Mechanical Engineering Changsha University of Science and TechnologyChangsha 410076Peopled Republic of China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082People’s Republic of China Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle of Hunan Province dhangsha University of Science and TechnologyChangsha 410114Peopled Republic of China

Minimum length scale control on real and void material phases in topology optimization is an important topic of research with direct implications on numerical stability and solution manufacturability.And it also is a challenge area of research due to serious conflicts of both the solid and the void phase element densities in phase mixing domains of the topologies obtained by existing methods.Moreover,there is few work dealing with controlling distinct minimum feature length scales of real and void phase materials used in topology designs.A new method for solving the minimum length scale controlling problem of real and void material phases,is proposed.Firstly,we introduce two sets of coordinating design variable filters for these two material phases,and two distinct smooth Heaviside projection functions to destroy the serious conflicts in the existing methods(e.g.Guest Comput Methods Appl Mech Eng 199(14):123-135,2009).Then,by introducing an adaptive weighted 2-norm aggregation constraint function,we construct a coordinating topology optimization model to ensure distinct minimum length scale controls of real and void phase materials for the minimum compliance problem.By adopting a varied volume constraint limit scheme,this coordinating topology optimization model is transferred into a series of coordinating topology optimization sub-models so that the structural topology configuration can stably and smoothly changes during an optimization process.The structural topology optimization sub-models are solved by the method of moving asymptotes(MMA).Then,the proposed method is extended to the compliant mechanism design problem.Numerical examples are given to demonstrate that the proposed method is effective and can obtain a good 0/1 distribution final topology.

关键词： Structural topology optimization Minimum length scale Manufacturability Coordinating density filter Heaviside projections Void phase

Advanced Anode Materials of Potassium Ion Batteries:from Zero Dimension to Three Dimensions

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Nano-Micro Letters 2021年第1期13卷 208-244页

作者： Jiefeng Zheng Yuanji Wu Yingjuan Sun jianhua rong Hongyan Li Li Niu Department of Materials Science and Engineering College of Chemistry and Materials ScienceJinan UniversityGuangzhou 510632People’s Republic of China Center for Advanced Analytical Science c/o School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006People’s Republic of China

Potassium ion batteries(PIBs)with the prominent advantages of sufficient reserves and economical cost are attractive candidates of new rechargeable batteries for large-grid electrochemical energy storage systems(EESs).However,there are still some obstacles like large size of K+to commercial PIBs applications.Therefore,rational structural design based on appropriate materials is essential to obtain practical PIBs anode with K+accommodated and fast diffused.Nanostructural design has been considered as one of the effective strategies to solve these issues owing to unique physicochemical properties.Accordingly,quite a few recent anode materials with different dimensions in PIBs have been reported,mainly involving in carbon materials,metal-based chalcogenides(MCs),metal-based oxides(MOs),and alloying materials.Among these anodes,nanostructural carbon materials with shorter ionic transfer path are beneficial for decreasing the resistances of transportation.Besides,MCs,MOs,and alloying materials with nanostructures can effectively alleviate their stress changes.Herein,these materials are classified into 0D,1D,2D,and 3D.Particularly,the relationship between different dimensional structures and the corresponding electrochemical performances has been outlined.Meanwhile,some strategies are proposed to deal with the current disadvantages.Hope that the readers are enlightened from this review to carry out further experiments better.

关键词： Potassium ion batteries Anode Structure design Nanomaterials Dimensions

Synthesis of 3D ordered porous polystyrene using silica template

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Chinese Science Bulletin 2001年第4期46卷 306-308页

作者： jianhua rong Zhenzhong Yang Kai Qi Xigao Jin Chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China

A rigid colloidal silica template was formed by self-assembly of the monodispersed silica spheres prepared according to Stober method. The silica template is highly ordered, which was verified by bright color effect due to Bragg diffraction and the results of SEM. The free radical polymerization of styrene was allowed within the interstices of the rigid template to result in the formation of the three-dimensional periodic silica/polystyrene nano-composites. The titled porous polystyrene was prepared by chemical decomposition of the template with concentrated aqueous hydrofluoric acid. Scanning electron microscopy characterization showed that the macroporous polystyrene has ordered arrays of the uniform pores replicated from the template. Moreover, it was found that the morphology of the as-synthesized macroporous polystyrene was greatly affected by the connectivity of the silica spheres treated under different conditions.

关键词： template synthesis colloidal silica three-dimensional order macroporous polystyrene.

Towards High-Energy and Anti-Self-Discharge Zn-Ion Hybrid Supercapacitors with New Understanding of the Electrochemistry

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Nano-Micro Letters 2021年第6期13卷 268-283页

作者： Yang Li Wang Yang Wu Yang Ziqi Wang jianhua rong Guoxiu Wang Chengjun Xu Feiyu Kang Liubing Dong College of Chemistry and Materials Science Jinan UniversityGuangzhou 511443People’s Republic of China Centre for Clean Energy Technology University of Technology SydneySydneyNSW 2007Australia Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055People’s Republic of China

Aqueous Zn-ion hybrid supercapacitors(ZHSs)are increasingly being studied as a novel electrochemical energy storage system with prominent electrochemical performance,high safety and low cost.Herein,high-energy and anti-self-discharge ZHSs are realized based on the fibrous carbon cathodes with hierarchically porous surface and O/N heteroatom functional groups.Hierarchically porous surface of the fabricated free-standing fibrous carbon cathodes not only provides abundant active sites for divalent ion storage,but also optimizes ion transport kinetics.Consequently,the cathodes show a high gravimetric capacity of 156 mAh g^(−1),superior rate capability(79 mAh g^(−1)with a very short charge/discharge time of 14 s)and exceptional cycling stability.Meanwhile,hierarchical pore structure and suitable surface functional groups of the cathodes endow ZHSs with a high energy density of 127 Wh kg−1,a high power density of 15.3 kW kg^(−1)and good anti-self-discharge performance.Mechanism investigation reveals that ZHS electrochemistry involves cation adsorption/desorption and Zn_(4)SO_(4)(OH)_(6)·5H_(2)O formation/dissolution at low voltage and anion adsorption/desorption at high voltage on carbon cathodes.The roles of these reactions in energy storage of ZHSs are elucidated.This work not only paves a way for high-performance cathode materials of ZHSs,but also provides a deeper understanding of ZHS electrochemistry.

关键词： Zn-ion hybrid supercapacitor Carbon material Fibrous cathode Hierarchical pore structure High-energy

基于硅光电倍增管和传统光电倍增管两种机型PET/CT临床成像条件下性能研究

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中华放射医学与防护杂志 2024年第5期44卷 428-435页

作者：苏雪松耿建华王奕斌王雪鹃郑容李静国家癌症中心、国家肿瘤临床医学研究中心、中国医学科学院北京协和医学院肿瘤医院核医学科北京100021

目的研究新一代硅光电倍增管(SiPM)正电子发射断层扫描与X射线计算机断层成像设备(PET/CT)与传统光电倍增管(PMT)PET/CT空间分辨力及图像质量,探讨不同的PET光电转换器(PMT与SiPM)和Q.Clear算法对PET空间分辨力、定量精度和图像质量的... 详细信息

目的研究新一代硅光电倍增管(SiPM)正电子发射断层扫描与X射线计算机断层成像设备(PET/CT)与传统光电倍增管(PMT)PET/CT空间分辨力及图像质量,探讨不同的PET光电转换器(PMT与SiPM)和Q.Clear算法对PET空间分辨力、定量精度和图像质量的影响。方法分别使用GE Discovery Elite型PET/CT(PMT PET/CT)和GE Discovery Meaningful Insights(MI)型PET/CT(SiPM PET/CT)对椭圆分辨力模体和NEMA NU2⁃2018图像质量模体成像。使用OSEM+PSF+TOF(VPFX⁃S)算法对所有模体原始数据进行图像重建,MI采集的模体数据额外使用Q.Clear算法重建,β取值范围150~550,间隔100。计算分辨力模体中5条线源在3个层面的径向、切向和轴向半高宽(FWHM)并求平均值。计算图像质量模体中小球的恢复系数(RC)、对比度百分比(CRC)、对比噪声比(CNR)、背景变异百分比(PBV)、背景变异系数(BCV)和不同图像层面肺插件残余误差(RE)。结果MI(VPFX⁃S)与Elite相比,在径向、切向和轴向FWHM分别降低4.25%~13.58%、7.00%~13.22%和6.02%~36.14%,小球RCmax无明显差异。MI(VPFX⁃S)提高小球CRC(10.17%~38.89%)与CNR(38.31%~94.95%),降低PBV(26.20%~33.82%)与BCV(31.29%~35.97%)。MI(Q.Clear)与MI(VPFX⁃S)相比,在径向、切向和轴向FWHM分别降低6.49%~45.02%、7.80%~35.60%和13.31%~36.80%,提高小球CNR(38.31%~94.95%),并降低PBV(26.20%~33.82%)与BCV(6.64%~10.31%),RC无明显差异。MI(Q.Clear)得到的CNR、RE和径向、切向、轴向FWHM均随β增大而增大,RC、CRC、PBV和BCV均随β增大而减小。结论在使用VPFX⁃S重建条件下,与PMT PET/CT相比,新一代SiPM PET/CT在空间分辨力、热灶对比度与探测能力和背景噪声方面均有所提高。相较于OSEM,Q.Clear算法改善了空间分辨力、定量精度与图像质量,但与β的选择有关。β值影响Q.Clear算法带来的收益,对小病灶的最大定量值影响最为明显,这点对提高临床诊断能力尤为重要。

关键词：正电子发射断层扫描传统光电倍增管硅光电倍增管空间分辨力图像质量

长江中下游麦区279个品种(系)小麦黄花叶病抗性研究

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核农学报 2024年第6期38卷 1005-1011页

作者：王汝琴范德佳何震天张容王建华韩燕陈士强江苏里下河地区农业科学研究所江苏扬州225007 扬州大学江苏省粮食作物现代产业技术协同创新中心江苏扬州225009

小麦黄花叶病是影响长江中下游麦区小麦(Triticum aestivum L.)产量的重要病害之一。为了筛选抗小麦黄花叶病种质资源,本研究对近30年来长江中下游麦区选育的279个小麦品种(系)进行田间小麦黄花叶病抗性鉴定,同时利用与抗小麦黄花叶病... 详细信息

小麦黄花叶病是影响长江中下游麦区小麦(Triticum aestivum L.)产量的重要病害之一。为了筛选抗小麦黄花叶病种质资源,本研究对近30年来长江中下游麦区选育的279个小麦品种(系)进行田间小麦黄花叶病抗性鉴定,同时利用与抗小麦黄花叶病主效数量性状基因座(QTL)QYm.nau-5A.1和QYm.nau-2D连锁的分子标记检测,以分析抗病QTL在品种(系)中的传递过程。结果显示,抗病材料为174个,占62.4%,其中仅含QYm.nau-5A.1和QYm.nau-2D的材料分别为30、98个,两个QTL均含的材料为9个,两个QTL均无的为37个,表明还存在其他抗病基因或QTL;感病材料为105个,占37.6%,其中仅含QYm.nau-5A.1和QYm.nau-2D的分别为6、25个,两个QTL均无的为74个。进一步分析小麦品种(系)系谱发现,长江中下游麦区小麦品种(系)的QYm.nau-5A.1主要来自于西风小麦,通过宁麦9号传递;QYm.nau-2D主要来自于苏麦6号、扬辐麦9311、郑麦9023,其中苏麦6号中的抗性QTL主要通过镇麦9号传递。本研究结果为长江中下游麦区小麦黄花叶病抗性分子育种及新抗病基因挖掘与利用提供了理论支撑。

关键词：小麦小麦黄花叶病抗性鉴定分子标记

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小麦黄花叶病抗性研究及育种应用进展

核农学报 2024年第5期38卷 861-869页

作者：范德佳王汝琴何震天张容王建华韩燕陈士强江苏里下河地区农业科学研究所江苏扬州225007

小麦黄花叶病是一种全球性的土传病毒病,严重时会导致小麦产量大幅下降。小麦黄花叶病毒(WYMV)是主要的病原体之一,属于马铃薯Y病毒科(Potyviridae)大麦黄花叶病毒属(Bymovirus),以禾谷多黏菌(Polymyxa graminis)为媒介感染小麦。目前... 详细信息

小麦黄花叶病是一种全球性的土传病毒病,严重时会导致小麦产量大幅下降。小麦黄花叶病毒(WYMV)是主要的病原体之一,属于马铃薯Y病毒科(Potyviridae)大麦黄花叶病毒属(Bymovirus),以禾谷多黏菌(Polymyxa graminis)为媒介感染小麦。目前已鉴定出14个抗WYMV的基因位点,图位克隆了1个抗病基因,证实了3个基因具有抗病性调控功能,已育成多个抗病小麦品种(系)。本文从小麦黄花叶病毒的病原体特性、病害分布、小麦抗性遗传和抗病育种等方面,综述了WYMV及小麦抗病性的研究进展,并对WYMV抗性基因挖掘和小麦抗病育种应用进行了展望。

关键词：小麦黄花叶病病毒特性抗病基因抗病育种

Synthesis and Characterization of Bionanoparticle-Silica Composites and Mesoporous Silica with Large Pores

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Nano Research 2009年第6期2卷 474-483页

作者： Zhongwei Niu Saswat Kabisatpathy Jinbo He LAndrew Lee jianhua rong Lin Yang Godfrey Sikha Branko N.Popov Todd S.Emrick Thomas P.Russell Qian Wang Department of Chemistry and Biochemistry and Nanocenter University of South CarolinaColumbiaSC 29208USA Department of Polymer Science and Engineering University of MassachusettsAmherstMA 01003USA Brookhaven National Laboratory UptonNY 11973USA Department of Chemical Engineering University of South CarolinaColumbiaSC 29208USA

A sol-gel process has been developed to incorporate bionanoparticles,such as turnip yellow mosaic virus,cowpea mosaic virus,tobacco mosaic virus,and ferritin into silica,while maintaining the integrity and morphology of the particles.The structures of the resulting materials were characterized by transmission electron microscopy,small angle X-ray scattering,and N2 adsorption desorption analysis.The results show that the shape and surface morphology of the bionanoparticles are largely preserved after being embedded into silica.After removal of the bionanoparticles by calcination,mesoporous silica with monodisperse pores,having the shape and surface morphology of the bionanoparticles replicated inside the silica,was produced,.This study is expected to lead to both functional composite materials and mesoporous silica with structurally well-defi ned large pores.

关键词： Mesoporous silica bionanoparticles virus ferritin sol gel

hs-CRP、NT-proBNP及NAR对急性冠状动脉综合征患者诊断价值分析

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转化医学杂志 2024年第2期13卷 208-211,217页

作者：贾蓉薛建华吴文上官晓雯常州市武进中医医院检验科江苏常州213161

目的探讨超敏C反应蛋白(hs-CRP)、氨基末端脑钠肽前体(NT-proBNP)及中性粒细胞与白蛋白比值(NAR)对急性冠状动脉综合征(ACS)患者的诊断价值。方法选取2020年6月—2022年9月收治的ACS 71例作为研究组,同期健康体检者56例作为对照组,并... 详细信息

目的探讨超敏C反应蛋白(hs-CRP)、氨基末端脑钠肽前体(NT-proBNP)及中性粒细胞与白蛋白比值(NAR)对急性冠状动脉综合征(ACS)患者的诊断价值。方法选取2020年6月—2022年9月收治的ACS 71例作为研究组,同期健康体检者56例作为对照组,并依照不同疾病类型和血管病变支数将研究组分为ST段抬高型心肌梗死(STEMI)组、非ST段抬高型心肌梗死(NSTEMI)组、不稳定型心绞痛(UAP)组及单支、双支、多支病变组各3个亚组。比较研究组与对照组、不同疾病类型和血管病变支数各3个亚组hs-CRP、NT-proBNP及NAR,探讨hs-CRP、NT-proBNP及NAR单独或联合对ACS的诊断价值。结果研究组hs-CRP、NT-proBNP及NAR均高于对照组;STEMI组、NSTEMI组和UAP组hs-CRP、NT-proBNP及NAR逐渐降低,单支、双支和多支病变组hs-CRP、NT-proBNP及NAR逐渐升高(P<0.05)。受试者工作特征曲线分析显示,hs-CRP、NT-proBNP和NAR单独或联合诊断ACS的曲线下面积分别为0.820、0.815、0.883及0.914,三者联合诊断ACS的曲线下面积高于单独诊断(P<0.05,P<0.01)。结论 hs-CRP、NT-proBNP及NAR三者联合对ACS的诊断价值较高。

关键词：急性冠状动脉综合征疾病类型血管病变支数超敏C反应蛋白氨基末端脑钠肽前体中性粒细胞与白蛋白比值诊断