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Optimizing multi-parameter distributed fiber sensors:a hybrid Rayleigh-Brillouin-Raman System approach

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Light(Science & Applications) 2024年第3期13卷 393-395页

作者： Kwang yong Song Dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid Rayleigh,Brillouin,and Raman distributed fiber sensing system has been developed for simultaneous measurement of multiple parameters.This system integrates 3-bit pulse coding for the Raman signal and the Brillouin amplification of the Rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber Rayleigh signal

Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： yong Qi Shufen Zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic crystals.SMPC can produce one or more temporary shapes through nanoscale deformation,memorizing current states.SMPC can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural color.As porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and mechanics.Herein,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and discussed.The primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface nanostructure.It aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of SMPCs.Finally,perspectives on future research directions and applications are also presented.It is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Overview of radar detection methods for low altitude targets in marine environments

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： YANG yong YANG Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath scattering.The performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target

Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

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Science China Chemistry 2024年第2期67卷 536-541页

作者： yong Wang Qiaoqiao Zhang yong-yong Cao Qi Liu Brendan F.Abrahams Jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward processes.In applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are uncommon.Herein,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,CP1a.It is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few minutes.The transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction conditions.Density functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product CP1b.This work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and stimuli.The insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

乡村振兴背景下农村集体经济的类型界定与治理效应

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北京工业大学学报（社会科学版） 2024年第1期24卷 62-71页

作者：夏冬夏柱智武汉大学社会学院湖北武汉430072

治理有效是中国乡村振兴战略实施的核心,以中部地区农村集体经济发展为研究对象,分析集体经济的发展特征、路径与治理效应,建立“集体经济-有效治理”的分析框架。在实施乡村振兴战略的各项举措支持下,中国中部农村集体经济经历了快速发... 详细信息

治理有效是中国乡村振兴战略实施的核心,以中部地区农村集体经济发展为研究对象,分析集体经济的发展特征、路径与治理效应,建立“集体经济-有效治理”的分析框架。在实施乡村振兴战略的各项举措支持下,中国中部农村集体经济经历了快速发展,形成了具有小规模却相对稳定的兜底型集体经济,这也是一种新型集体经济。兜底型集体经济适应中西部乡村发展的现实,具有促进村庄有效治理的积极效应,具体表现为促进了村级组织稳定运转、维持小微公共品有序供给、为留守农民提供基本公共服务等。提出中国应立足于中西部集体经济发展现实,避免集体经济发展实践中盲目“经营村庄”的实践误区,分类推进集体经济发展,加强村社集体统筹能力建设,以实现村庄有效治理。

关键词：乡村振兴兜底型集体经济新型集体经济村级治理中西部乡村发展

农村宅基地有偿使用制度改革的效应和问题:东部D镇例证

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中国社会科学院大学学报 2024年第2期44卷 122-134+159-160页

作者：夏柱智武汉大学社会学院

宅基地改革是乡村振兴背景下乡村建设的重要内容,关系到保障农户基本居住条件的社会公正,深化改革需要审慎稳妥。宅基地有偿使用制度有多样化的路径,分散在宅基地初始取得、利用及转让退出环节。产权经济学从强化宅基地财产属性出发着... 详细信息

宅基地改革是乡村振兴背景下乡村建设的重要内容,关系到保障农户基本居住条件的社会公正,深化改革需要审慎稳妥。宅基地有偿使用制度有多样化的路径,分散在宅基地初始取得、利用及转让退出环节。产权经济学从强化宅基地财产属性出发着力构建宅基地市场体系,宅基地初始取得的市场化是宅基地初始取得的有偿使用的独特类型,仅在少数地区得到持续探索。本文基于对我国东部地区一个发达工业镇的村庄调研,发现在宅基地财产属性凸显的背景下,宅基地的市场化在一定程度上有利于集体经济发展、促进乡村建设,实现宅基地作为集体土地资源的价值,但在运行过程中容易形成社会排斥问题,违背社会公正原则,损害普通农民的民生保障。宅基地“三权分置”改革探索分置宅基地的“资格权”和“使用权”,但是在地方实践中,“资格权”并不能解决宅基地的财产性和保障性的矛盾,需要深入辨析。建议在坚持宅基地福利性配置原则的前提下,审视宅基地改革和农民利益及乡村建设的制度关联。

关键词：宅基地改革宅基地有偿使用社会公正三权分置乡村振兴

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

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Current Medical Science 2024年第3期44卷 463-474页

作者： Rui HE yong CHEN Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： Xing Chen yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in water.The findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying exponentially.Increasing the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the JPC.The optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in water.Material density plays a crucial role in the velocity decay pattern of the JPC during penetration.JPC with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are similar.Consequently,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge warhead.Finally,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Irradiation effects in polycarbonate induced by 2.1 GeV Kr ions

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Nuclear Science and Techniques 2003年第4期14卷 242-245页

作者： TIANHui-Xian JINYun-Fan zhuzhi-yong SUNYou-Mei WANGZhi-Guang InstituteofAppliedPhysicsandComputationalMathematics Beijing100088 InstituteofModernPhysics theChineseAcademyofSciencesLanzhou730000

Polycarbonate foil stacks were irradiated with 2.1 GeV Kr ions under vacuum at room temperature.The modifications in chemical structure induced by the irradiation were studied by means of Fourier transform infra-red (FTIR) and ultraviolet visible (UV/VIS) spectroscopies. FTIR measurements reveal that material degradationsthrough bond breaking are the main effects. Alkyne end groups are produced by the irradiation. UV/VIS measure-ments indicate a shifting of the absorption edge from ultraviolet towards visible, and a strong increase of absorbancein the ultraviolet and visible regions. The changes in absorbance induced by the irradiation at wavelengths of 380 nm,450 nm and 500 nm scale well with Sne (Se is electronic energy loss) where the value of n increases from 1.69 to 2.02with increasing of the wavelength. The results are briefly discussed.

关键词：辐射防护聚碳酸酯氪 Fourier变换降解机制锗