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Orbital period changes of the W UMa binary YY Eri

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Research in Astronomy and Astrophysics 2018年第9期18卷 13-20页

作者： Ting yu Ke Hu yun-xia yu Fu-yuan xiang Department of Physics Xiangtan University

Orbital period changes of the W UMa-type binary YY Eri are analyzed by using all photoelectric and ccd times of light minimum. The results show that its orbital period is undergo- ing a secular increase superposed on two cyclic oscillations. The continuous increase at the rate of dP/dt = 6.3806 × 10^-8 d yr^-1 may be accounted for by mass transfer from the less massive com- panion to the more massive one. Two periodic variations with periods of 38.6192 and 22.3573 yr may be attributed to the light-time effect of a faint third star and the cyclic magnetic activity of the system, respectively.

关键词： stars binaries close - stars binaries eclipsing - stars individual (YY Eri)

Self-Trapped Exciton Photoluminescence from Polycrystalline K2AgI3 Obtained by Solid-State Reaction Method

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Chinese Physics Letters 2011年第1期28卷 201-204页

作者： DAI Peng XU Zou-Ming WANG yu-xia Department of Materials Science and Engineering University of Science and Technology of China Hefei 230026 School of Physics and Material Science Anhui University Hefei 230039

Polycrystalline K2AgI3 is synthesized by solid-state reaction at 403K using AgI and KI as starting materials. X-ray diffraction, photoluminescence （PL） spectra, photoluminescenee excitation （PLE,） spectra, electron para- magnetic resonance （EPR） and absorption spectra are employed to investigate the structure and photo-physical properties of such material. A broad luminescence band centered at about 608nm at 180K with large Stokes shift is found. When the temperature rises to about 300K, an obvious PL blue-shift, PL intersity weakening, and an emission band broadening are observed. It is suggested that the emission at about 608 nm may originate from the recombination of self-trapped exeitons.

关键词： Condensed matter: electrical magnetic and optical Surfaces interfaces and thin films

A Water/Land Segmentation Algorithm Based on an Improved Chan-Vese Model with Edge Constraints of Complex Wavelet Domain

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Chinese Journal of Electronics 2015年第2期24卷 361-365页

作者： MAO Chenglin WAN Shouhong yuE Lihua xia yu School of Computer Science and Technology University of Science and Technology of China

A novel model for segmentation of water/land in Synthetic aperture radar(SAR) images is presented. The proposed model calculates the global matrix of oriented gradient of histograms on wavelet subbands based on the multi-scale property, shift invariance and directional selectivity of Complex wavelet transform(CWT), then acquires edge information by thresholding the matrix. It improves the traditional Chan-vese(CV) model by adding the constraint of extracted edge information. A new water/land segmentation algorithm is then proposed based on the new model. The performance of proposed method is compared with some other existing algorithms and the experimental results confirm its effectiveness.

关键词： Water/land segmentation Complex wavelet transform Multi-scale Orientation selectivity Edge information Chan-vese model

结构重塑与行为调适:数字技术赋能居民参与社区公共安全治理的实现逻辑

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湘潭大学学报(哲学社会科学版) 2025年第1期49卷 26-33页

作者：刘超夏湘玉湘潭大学公共管理学院湖南湘潭411105

居民参与是社区公共安全治理的重要基石,也是提升社区治理效能的关键支撑。数字时代背景下,如何充分发挥技术赋能作用,推动社区居民深度参与公共安全治理成为数字时代社区公共安全共同体建设的核心议题。研究基于技术嵌入理论,构建了数... 详细信息

居民参与是社区公共安全治理的重要基石,也是提升社区治理效能的关键支撑。数字时代背景下,如何充分发挥技术赋能作用,推动社区居民深度参与公共安全治理成为数字时代社区公共安全共同体建设的核心议题。研究基于技术嵌入理论,构建了数字赋能居民参与社区公共安全治理的结构与行为双维分析框架。并以Y区扁平化治理改革为实践案例,探讨了数字技术赋能居民参与社区公共安全治理的实现逻辑。研究发现,数字技术赋能社区公共安全治理居民参与存在两重逻辑:其一是“结构重塑”逻辑,即数字技术通过重塑政民互动的组织结构、权力结构和时空结构,拓展居民参与的渠道与空间;其二是“行为调适”逻辑,即数字技术通过转变居民理念、提升居民能力、优化居民行为模式,有效激发其参与的意愿和行动力。

关键词：数字赋能居民参与公共安全治理

Pathogenic roles of long noncoding RNAs in melanoma: Implications in diagnosis and therapies

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Genes & Diseases 2023年第1期10卷 113-125页

作者： yuai xiao yu xia yuchong Wang Chunyu Xue Department of Plastic Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China

Melanoma is one of the most dangerous types of cutaneous neoplasms,which are pigment-producing cells of neuroectodermal origin found all over the body.A great deal of research is focused on the mechanisms of melanoma to promote better diagnostic and treatment options for melanoma in its advanced *** progression of melanoma involves alteration in different levels of gene *** the successful implementation of next-generation sequencing technology,an increasing number of long noncoding RNAs(lncRNAs)sequences have been discovered,and a significant number of them have phenotypic effects in both in vitro and in vivo studies,implying that they play an important role in the occurrence and progression of human cancers,particularly melanoma.A number of evidence indicated that lncRNAs are important regulators in tumor cell proliferation,invasion,apoptosis,immune escape,energy metabolism,drug resistance,epigenetic *** better understand the role of lncRNAs in melanoma tumorigenesis,we categorize melanomaassociated lncRNAs according to their cellular functions and associations with gene expression and signaling pathways in this *** on the mechanisms of lncRNA,we discuss the possibility of lncRNA-target treatments,and the application of liquid biopsies to detect lncRNAs in melanomadiagnosisandprognosis.

关键词： Cellular functions Long noncoding RNAs Melanoma

智慧医疗在肝移植患者延续性管理中应用的范围综述

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中华护理杂志 2025年第4期60卷 507-512,F0003页

作者：孙旭周智聪夏雨安晓杨滕仝紫薇王红山东第一医科大学第一附属医院护理部济南市250014 山东第一医科大学附属省立医院护理部

目的对智慧医疗在肝移植患者延续性管理中的应用研究进行范围综述,旨在为未来开展智慧化肝移植管理提供参考。方法系统检索PubMed、Embase、CINAHL、Web of Science、Cochrane Library、Scopus、中国知网、万方数据库、维普数据库和中... 详细信息

目的对智慧医疗在肝移植患者延续性管理中的应用研究进行范围综述,旨在为未来开展智慧化肝移植管理提供参考。方法系统检索PubMed、Embase、CINAHL、Web of Science、Cochrane Library、Scopus、中国知网、万方数据库、维普数据库和中国生物医学文献数据库中的相关研究。检索时限为建库至2024年9月30日。对纳入的文献进行筛选和归纳总结。结果共纳入19篇文献。智慧医疗主要开展形式为应用程序、智慧医疗设备、远程康复平台。内容要素包括移植健康管理、康复方案规划、健康数据监测、远程医疗咨询、心理社会支持、随访监督。评价指标涉及生理指标、自我管理能力、健康相关生活质量、肝移植结局、患者满意度、可行性指标。结论智慧医疗在肝移植患者延续性管理应用中具有可行性和有效性,建议医护人员结合临床实际情况整合智慧医疗多元实践形式、深化内容要素和完善评价指标体系,以期提升肝移植患者延续性管理质量。

关键词：肝移植智慧医疗延续性管理护理范围综述

Chitosan derived carbon membranes as protective layers on zinc anodes for aqueous zinc batteries

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 621-629页

作者： Haichao Li Zengwu Wei yu xia Junshan Han Xing Li School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

Aqueous zinc batteries with low cost and inherent safety are considered to be the most promising energy storage ***,they suffer from poor cycling stability and low coulombic efficiencies caused by the adverse zinc dendrites on the anodes during the discharging/charging *** is a kind of natural amino polysaccharide,which is rich in nitrogen and *** sintered at high temperatures,carbon membranes have been achieved with excellent conductivity and graphitization degree,which could enhance the ability to induce zinc ion uniform deposition to some *** this work,a type of carbon membrane using chitosan as raw materials has been fabricated by sintering,and then assembled as the protect layers in aqueous zinc *** results show that the samples could retain smoother surfaces when adopting the sintering temperature of 800℃,and the assembled batteries are able to achieve about 700 h at a current density of 0.25m A·cm^(-2),which is far longer than those of the similar batteries without any carbon membranes.

关键词： carbon membrane dendrites chitosan sintering process zinc batteries

Selective oxidation mediated synthesis of unique SexTey nanotubes, their assembled thin films and photoconductivity

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Nano Research 2018年第2期11卷 665-675页

作者： yuan Yang Guo-Qiang Liu Min-Rui Gao yu xia Shu-Hong yu Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at the Microscale Collaborative Innovation Centre of Suzhou Nano Science and Technology CAS Centre for Excellence in Nanoscience Department of Chemistry Hefei Science Centre of CAS University of Science and Technology of China Hefei China

One-dimensional hollow nanostructures have potential applications in many fields and can be fabricated using various methods. Herein, a selective-oxidation route for the synthesis of unique SexTey nanotubes （STNTs） with a controlled morphology using TexSey@Se core-shell nanowires （TSSNWs） as a template is reported. Because of the lower redox potential of TeO2/Te compared to that of H2SeO3/Se, the Te in TSSNWs can be preferentially oxidized by an appropriate oxidant of HNO2 to form STNTs. The inner diameters and wall thicknesses of the STNTs can be tuned by modulating the core diameters and shell thicknesses of the TSSNWs, respectively. The STNTs can be assembled into a monolayer composed of well-arranged nanotubes using the Langmuir-Blodgett technique. A device based on films stacked with 10 STNT monolayers was fabricated to investigate the photocoductivity of the STNTs. The STNTs exhibited a good photoresponse over the whole ultraviolet-visible spectrum, revealing their votential for application in ovtoelectronic devices.

关键词： selective oxidation core-shell nanowires nanotubes assembled thin films photoconductivity

Exfoliation and dispersion of graphene in ethanol-water mixtures

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Frontiers of Materials Science 2012年第2期6卷 176-182页

作者： Wei-Wei LIU Bao-yu xia xiao-xia WANG Jian-Nong WANG Shanghai Key Laboratory for Laser Processing and Materials Modification School of Materials Science and EngineeringShanghai Jiao Tong University800 Dong Chuan RoadShanghai 200240China School of Materials Science and Engineering Tongji University1239 Siping RoadShanghai 200092China Key Laboratory of Safety Science of Pressurized System(Ministry of Education) ScHool of Mechanical and Power EngineeringEast China University of Science and Technology130 Meilong RoadShanghai 200237China

Graphene has attracted much attention as a new nano-carbon for its unique structure and properties. However, production and dispersion of unfunctionalized graphene are still big challenges. Herein, we demonstrate a simple method for preparation and dispersion of such graphene with low cost and non toxicum. This approach is achieved by exfoliating graphite in an ethanol/water mixture and forming stable dispersion of mono- and few-layer graphenes. The ratio of ethanol/water in the mixture is found to be crucial to both the exfoliation and dispersion processes. Exfoliation in pure water or pure ethanol produces no graphene. This method avoids the conventional use of harsh oxidants and surfactants; therefore, the graphitic structure is well maintained without destruction. Benefiting from the use of ethanol and water, it can be easy to prepare transparent and conductive graphene films by vacuum filtering or spray method, and does not need special post-treatment to remove the impurity, which could be beneficial for potential applications in electronic, optic and energy areas.

关键词： graphene liquid-phase exfoliation transparent conductive film solubilityparameter