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Research status and prospects of the fractal analysis of metal material surfaces and interfaces

International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 20-38页

作者： Qinjin Dai Xuefeng liu Xin ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation Center for materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

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Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie Z.li Nagendran Ramalingam Shaomin li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

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Optical Properties of Plasmon Resonances with Ag/SiO2/Ag Multi-Layer Composite Nanoparticles

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Chinese Physics Letters 2010年第6期27卷 107-109页

作者： ma Ye-wan ZHANG li-Hua WU Zhao-wang ZHANG Jie School of Physics and Electric Engineering Anqing Teachers College Anqing 246011

Optical properties of plasmon resonance with Ag/SiO2/Ag multi-layer nanoparticles are studied by numerical simulation based on Green＇s function theory. The results show that compared with single-layer Ag nanoparticles, the multi-layer nanoparticles exhibit several distinctive optical properties, e.g. with increasing the numbers of the multi-layer nanoparticles, the scattering efficiency red shiRs, and the intensity of scattering enhances accordingly. It is interesting to find out that slicing an Ag-layer into multi-layers leads to stronger scattering intensity and more ＂hot spots＂ or regions of stronger field enhancement. This property of plasmon resonance of surface Raman scattering has greatly broadened the application scope of Raman spectroscopy. The study of metal surface plasmon resonance characteristics is critical to the further understanding of surface enhanced Raman scattering as well as its applications.

关键词：复合纳米粒子等离子体共振光学性能表面增强拉曼散射银纳米粒子格林函数理论散射强度共振拉曼散射

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Evolutionary selection for regression test cases based on diversity

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Frontiers of Computer Science 2021年第2期15卷 201-203页

作者： Baoying ma li wan Nianmin YAO Shuping FAN Yan ZHANG School of Health management Mudanjiang Medical UniversityMudanjiang157011China Department of intelligence and Computing Tianjin UniversityTianjin300350China School of Computer Science and Technology Dalian University of TechnologyDalian116024China School of Computer and Information Technology Mudanjiang Normal UniversityMudanjiang157011China

1 Introduction Regression testing refers to retest code after modification to ensure that changes will not introduce new faults or cause faults in other lines of code[1].Regression test selection(RTS)is one of the predominant *** identifies test cases that are relevant to test recent changes in an application and seeks to reduce the number of test suite while preserving the capability to reveal faults[2].

关键词： preserving predominant changes

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Functional Amphiphilic Poly(2-oxazoline)Block Copolymers as Drug Carriers:the Relationship between Structure and Drug Loading Capacity

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Chinese Journal of Polymer Science 2021年第7期39卷 865-873页

作者： Si Dong Sheng ma Zhi-lin liu li-li ma Yu Zhang Zhao-Hui Tang Ming-Xiao Deng wan-Tong Song College of Chemistry Northeast Normal UniversityChangchun 130024China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Poly(2-oxazoline)(POx)is a kind of polymeric amides that can be viewed as conformational isomers of polypeptides with excellent cyto-and hemo-compatibility,and is promising to be used as drug ***,the drug loading capacity(DLC)of POx for many drugs is still low except several hydrophobic ones including paclitaxel(PTX).Herein,we prepared a series of amphiphilic POx block copolymers with various functional groups,and investigated the relationship between functional structures and the *** POxs with benzyl,carboxyl,and amino groups in the side-chain were synthesized based on a poly(2-methyl-2-oxazoline)-block-poly(2-buty1-2-oxazoline-co-2-buteny1-2-oxazoline)(PMeOx-P(nBuOx-co-ButenOx),PMBEOx)precursor,followed by click reaction between vinyl and the 2-phenylethanethiol,thioglycolic acid and *** thin-film hydration method,eight commonly used drugs with various characteristics were encapsulated within these functional POx *** found that amine-containing drugs were more easily encapsulated by POx with carboxyl groups,while amine functionalities in POx enhanced the loading capacity of drugs with carboxyl *** addition,n-n interactions resulted in enhanced DLC of most drugs,except several hydrophobic drugs with aromatic to total carbon ratios less than *** general,we could successfully encapsulate all the selected drugs with a DLC%over 10%using properly selected functional *** above results confirm that the DLC of polymeric carriers can be adjusted by modifying the functional groups,and the prepared series of functional POxs provide an option for various drug loadings.

关键词： Poly(2-oxaozoline) Polymeric micelles Drug loading π-πInteraction Electrostatic interaction

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西南天山榴辉岩相脉体记录的俯冲带多期流体作用

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岩石学报 2025年第1期41卷 183-197页

作者：吕佳阳李继磊王钟瑞马智佩中国科学院地质与地球物理研究所岩石圈演化与环境演变重点实验室北京100029 中国科学院大学地球与行星科学学院北京101408

俯冲带是全球最大的物质循环系统,控制着壳幔相互作用、岛弧岩浆作用、成矿物质聚集和全球元素循环等诸多重要的地质过程。俯冲带流体作为板片向上覆地幔楔进行物质传输的重要媒介,在上述地质过程中扮演着关键角色。基于岛弧火山岩地球... 详细信息

俯冲带是全球最大的物质循环系统,控制着壳幔相互作用、岛弧岩浆作用、成矿物质聚集和全球元素循环等诸多重要的地质过程。俯冲带流体作为板片向上覆地幔楔进行物质传输的重要媒介,在上述地质过程中扮演着关键角色。基于岛弧火山岩地球化学特征、高温高压实验、相平衡模拟,以及高压-超高压变质岩的研究,我们对俯冲带流体基本特征及其地球化学行为已经有了较为深刻的认识,然而,目前对俯冲带流体作用的复杂性,如多期流体作用,还缺少深入的理解。本文对西南天山高压-超高压变质带榴辉岩中一条含石英-绿帘石-铁白云石-硫化物的高压脉开展了详细的岩石学、地球化学研究。脉体中有绿辉石、铁白云石、金红石等特征高压矿物的产出,暗示其代表的流体作用发生于高压条件下。脉体与主岩榴辉岩界线截然,之间无蚀变带/过渡带/交代晕产出,说明主岩榴辉岩与迁移流体之间没有发生显著的水-岩交换反应。脉体矿物(如绿帘石、铁白云石、黄铁矿等)的多期生长特征及其成分差异研究揭示出至少三期流体作用。前两期流体作用均发生于高压条件下,特征如下:(1)两期流体分别以两期矿物组合(Ep^(1)-Dol^(1)-Py^(1)组合以及Ep^(2)-Dol^(2)-Py^(2)组合)为代表,在第二期流体作用下,第一期流体沉淀的矿物(如Dol^(1)等)发生了明显的溶解-再沉淀作用;(2)两期流体性质均以富Ca、Si,含C_(2)、S为特征,第一期流体较第二期流体富Fe贫Mg,富Ni贫Co,富轻稀土元素(LREE);(3)两期黄铁矿的δ^(34)S值分别为-8‰和-5‰,暗示这两期流体均主要来源于俯冲沉积物,且第二期流体可能有更多俯冲洋壳或蛇纹岩脱水流体的参与;(4)两期流体作用下,碳酸盐矿物和硫化物显示出耦合共生的特点,暗示C、S在流体作用下可能具有协同演化(如溶解-迁移-沉淀)的关系。第三期流体作用以绿帘石+铁白云石反应生成方解石+绿泥石、绿帘石边部(与黄铁矿相邻处)发生成分改造为特征,流体作用发生在高压岩石折返的退变质阶段,记录了退变质流体的信息。本研究通过榴辉岩高压脉体中多期矿物生长的特征,揭示了俯冲带内多期流体作用,对深入理解俯冲带流体性质、流体来源、以及俯冲带关键挥发分元素的耦合演化信息,具有重要的科学意义。

关键词：西南天山榴辉岩高压脉体俯冲带流体多期流体作用

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Degradation of benzothiophene in diesel oil by LaZnAl layered double hydroxide: photocatalytic performance and mechanism

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Petroleum Science 2019年第1期16卷 173-179页

作者： li-Guo Gao Huan-Xiang li Xiao-li Song wan-Lu li Xiang-Rong ma School of Chemistry and Chemical Engineering Yulin University Department of Chemistry Tsinghua University

A new type of photocatalytic La^(3+)–Zn^(2+)–Al^(3+)–MoO_4^(2-) layered double hydroxide(LDH) material(molar ratio, La/Zn/Al = 1:7:2) was prepared by a complexing agent-assisted homogeneous precipitation technique. The structure of the prepared LDH material was systematically studied. Under UV irradiation, the desulfurization efficiency of the LDH material was 87% in 2 h. For La^(3+)–Zn^(2+)–Al^(3+)–MoO_4^(2-) LDH material, the introduction of MoO_4^(2-) increased the interlayer space for promoting the adsorption of benzothiophene(BT), and MoO_4^(2-) might provide active sites for the oxidation of BT, resulting in the high desulfurization efficiency.

关键词： LDH Homogeneous precipitation Photocatalytic activities Catalytic oxidation mechanism

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A Review on Vibration Control of Multiple Cylinders Subjected to FlowInduced Vibrations

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China Ocean Engineering 2024年第2期38卷 183-197页

作者： XU wan-hai ma Ye-xuan State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300350China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The fatigue damage caused by flow-induced vibration(FIV)is one of the major concerns for multiple cylindrical structures in many engineering *** FIV suppression is of great importance for the security of many cylindrical *** active and passive control methods have been employed for the vibration suppression of an isolated cylinder undergoing vortex-induced vibrations(VIV).The FIV suppression methods are mainly extended to the multiple cylinders from the vibration control of the isolated *** to the mutual interference between the multiple cylinders,the FIV mechanism is more complex than the VIV mechanism,which makes a great challenge for the FIV *** efforts have been devoted to vibration suppression of multiple cylinder systems undergoing FIV over the past two *** control methods,such as helical strakes,splitter plates,control rods and flexible sheets,are not always effective,depending on many influence factors,such as the spacing ratio,the arrangement geometrical shape,the flow velocity and the parameters of the vibration control *** FIV response,hydrodynamic features and wake patterns of the multiple cylinders equipped with vibration control devices are reviewed and *** FIV suppression efficiency of the vibration control methods are analyzed and compared considering different influence *** research on the FIV suppression of multiple cylinders is suggested to provide insight for the development of FIV control methods and promote engineering applications of FIV control methods.

关键词： flow-induced vibration vibration control multiple cylinders tandem side-by-side staggered

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Detection of intermediates in the TiO_2-assisted photodegradation of Rhodamine B under visible light irradiation

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Journal of Environmental Sciences 2007年第7期19卷 892-896页

作者： li Jing-yi ma wan-hong LEI Peng-xiang ZHAO Jin-cai College of Chemistry and Chemical Engineering Inner Mongolia University Hohhot Inner Mongolia 010021 China. Centre for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The photocatalytic degradation of dye Rhodamine B （RhB） in the presence of TiO2 nanostdpe or P25 under visible light irradiation was investigated. The degradation intermediates were identified using Infrared spectra （IR spectra）, ^1H nuclear magnetic resonance （^1HNMR） spectra, and gas chromatography-mass spectroscopy （GC-MS）. The IR and the ^1HNMR results showed that the large conjugated chromophore structure of RhB was efficiently destroyed under visible light irradiation in both the photocatalytic systems （TiO2 nanostfipe or P25 and Rhodamine B systems）. GC-MS results showed that the main identified intermediates were ethanediotic acid, 1,2-benzenedicarboxylic acid, 4-hydroxy benzoic acid and benzoic acid, which were almost the same in the TiO2 nanostdpes and P25 systems. This work provides a good insight into the reaction pathway（s） for the TiO2-assisted photocatalytic degradation of dye pollutants under visible light irradiation.

关键词： TiO2 visible light irradiation Rhodamine B (RhB)

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Experimental and Numerical Study on the Gas Explosion in Urban Regulator Station

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Journal of Beijing Institute of Technology 2020年第2期29卷 195-208页

作者： Zhenyi liu Yuanyuan ma Yuan Ren Mingzhi li Pengliang li Song wan State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China QHSE Department Sino-Pipeline International Company Ltd.Beijing 102206China

Regulator station is an important part in the urban gas transmission and distribution *** gas explosion occurs,the real explosion process and consequences of methane gas explosion in the regulator station were not revealed *** this study,a full-scale experiment was carried out to simulate the regulator station explosion process,and some numerical simulations with a commercial CFD software called FLACS were conducted to analyze the effect of ignition and vent conditions on the blast overpressure and flame *** experimental results demonstrated that the peak overpressure increased as the distance from the vent increased within a certain *** the maximum overpressure appeared 3 m away from the door,which was about 36.6 *** was found that the pressure-time rising curves obtained from the simulation are basically the same as the ones from the experiment,however,the time of reaching the peak pressure was much *** numerical simulation results show that the peak overpressures show an increase trend as the ignition height decreased and the vent relief pressure *** indicates that the damage and peak overpressure of gas explosion could be well predicted by FLACS in different styles of regulator *** addition,the results help us to understand the internal mechanism and development process of gas explosion *** also offers technical support for the safety protection of the urban regulator station.

关键词： regulator station gas explosion full-scale experiment numerical simulation overpressure distribution

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