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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1294-1301页

作者： You-zheng sun Jin-bao Li Daniel Wellburn Chang-sheng Liu Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) Northeastern University

To improve the wear resistance of Cr5 steel, wear-resistant layers with lamellar eutectic microstructure were fabricated by laser surface alloying（LSA）, which is dependent on the in situ reaction between Cr and B_4C. Our results indicated that the hypoeutectic structures of the LSA layers were divided into interdendritic eutectic structures and dendrites. The area fraction of the eutectic structures increased with increasing laser scanning speed, which improved the hardness and wear resistance of the LSA layers. The average hardness of the LSA layer prepared at a scanning speed of 8 mm/s was HV_（0.2） 883.9, which was 1.8 times greater than that of the traditional quenched layer（approximately HV 480）. After sliding for 659.4 m, the specimen prepared at a scanning speed of 8 mm/s exhibited a volume loss of 0.0323 mm^3, which was only 29.5% of the volume loss of the traditional quenched specimen.

关键词： eutectic wear resistance laser alloying hardness

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大型射电望远镜主反射面调整方法研究

天文学报 2024年第2期65卷 42-52页

作者：孙正雄王锦清虞林峰张志斌王广利中国科学院上海天文台上海200030 中国科学院射电天文重点实验室南京210023 上海市空间导航与定位技术重点实验室上海200030 中国科学院大学北京100049

随着毫米波天文学和空间通信的重要性日益提高,对天线性能提出了越来越高的要求,而天线性能往往受到其反射器表面精度的限制.微波全息技术是一种快速有效的检测反射面天线表面轮廓的测量技术.通过微波全息测量得到天线口径场,计算天马65... 详细信息

随着毫米波天文学和空间通信的重要性日益提高,对天线性能提出了越来越高的要求,而天线性能往往受到其反射器表面精度的限制.微波全息技术是一种快速有效的检测反射面天线表面轮廓的测量技术.通过微波全息测量得到天线口径场,计算天马65m射电望远镜反射面与理想抛物面的偏差.天马65m射电望远镜的主反射面板是放射状的,有14圈.面板的每个角都固定在面板下方促动器的螺栓上进行上下移动,且相邻面板交点处的拐角共用一个促动器.采用平面拟合的方法可以计算各块面板拐角处的调整值,但是同一个促动器会得到4个不同的调整量.通过平面拟合,同时以天线照明函数为权重的平差计算方法得到相邻面板拐角的一个平差值,即天马65m射电望远镜1104个促动器的最佳调整值.通过多次调整和新算法的应用,天马65m射电望远镜反射面的面形精度逐渐提高到了0.24mm.

关键词：望远镜:射电,面形误差,天线效率方法:微波全息,数据分析

Classification and Net Primary Productivity of the Southern China's Grasslands Ecosystem Based on Improved Comprehensive and Sequential Classification System(CSCS) Approach

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Journal of Integrative Agriculture 2014年第4期13卷 893-903页

作者： sun zheng-guo sun Cheng-ming ZHOU Wei JU Wei-min LI Jian-long College of Animal Sciences and Technology Nanjing Agricultural University School of Life Science Nanjing University International Institute for Earth System Science Nanjing University

This research classified vegetation types and evaluated net primary productivity （NPP） of southern China＇s grasslands based on the improved comprehensive and sequential classification system （CSCS）, and proposed 5 thermal grades and 6 humidity grades. Four classes of grasslands vegetation were recognized by improved CSCS, namely, tundra grassland class, typical grassland class, mixed grassland class and alpine grassland class. At the type level, 14 types of vegetations （9 grasslands and 5 forests） were classified. The NPP had a trend to decrease from east to west and south to north, and the annual mean NPP was estimated to be 656.3 g C m-2 yr-1. The NPP value of alpine grassland class was relatively high, generally more than 1200 g C m2 yr-1. The NPP value of mixed grassland class was in a range from 1 000 to 1200 g C m-2 yr-1. Tundra grassland class was located in southeastern Tibet with high elevation, and its NPP value was the lowest （〈600 g C m＇2yrl）. The typical grassland class distributed in most of the area, and its NPP value was generally from 600 to 1000 g C m-2 yr-1. The total NPP value in the study area was 68.46 Tg C. The NPP value of typical grassland class was the highest （48.44 Tg C）, and mixed grassland class was the second （16.54 Tg C）, followed by alpine grassland class （3.22 Tg C）, with tundra grassland class being the lowest （0.25 Tg C）. For all the grasslands types, the total NPP of forest meadow was the highest （34.81 Tg C）, followed by sparse forest brush （16.54 Tg C）, and montane meadow was the lowest （0.01 Tg C）.

关键词： improved CSCS hydro-thermal pattern southem China grasslands classes and types net primary productivity (NPP)

A myofiber-derived secreted factor for muscle regeneration

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Life Metabolism 2023年第4期2卷 5-6页

作者： Fang Xiao zheng sun Department of Cadress Medical Care and Geriatrics The Second HospitalCheeloo College of MedicineShandong UniversityJinanShandong 250033China Department of Medicine-Division of Endocrinology Diabetesand MetabolismBaylor College of MedicineHoustonTX 77030United States Department of Molecular and Cellular Biology Baylor College of MedicineHoustonTX 77030United States

A recent study shed light on transcriptional regulation of myofiber-derived Dkk3,a secreted protein involved in muscle differentiation,which has therapeutic implications in damage-induced muscle regeneration and obesity-associated muscle *** in muscle regeneration have been centered on resident muscle stem cells(MuSCs),also known as satellite *** muscle damage,quiescent MuSCs are activated to enter the cell cycle and start *** give rise to myogenic progenitor cells or myoblasts that differentiate into *** fuse with each other to form multinucleate myotubes that further mature to become myofibers[1].Each of the above stages is characterized by cascades of gene expression patterns orches-trated by distinct transcription factors receiving external signals from the microenvironment in alliance with physical interactions between the differentiating muscle cells and the other cell types in the muscle[2].

关键词： atrophy fiber obesity

PICU转科患儿照顾者准备度量表的编制及信效度检验

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护理学杂志 2024年第15期39卷 37-40,46页

作者：褚忠霞李霞韩娟张晴晴王秀秀孙铮青岛大学附属泰安市中心医院新生儿监护室山东泰安271000 山东第一医科大学护理学院

目的编制PICU转科患儿照顾者准备度量表,并检验其信效度。方法以Meleis过渡理论和Roy适应模式为理论依据,通过文献回顾、专家函询和预调查编制初始量表。采用便利抽样法,选取PICU转科患儿的397名照顾者作为调查对象,对量表进行项目分析... 详细信息

目的编制PICU转科患儿照顾者准备度量表,并检验其信效度。方法以Meleis过渡理论和Roy适应模式为理论依据,通过文献回顾、专家函询和预调查编制初始量表。采用便利抽样法,选取PICU转科患儿的397名照顾者作为调查对象,对量表进行项目分析和信效度检验。结果PICU转科患儿照顾者准备度量表包含5个维度共23个条目。探索性因子分析提取5个公因子,累积方差贡献率为69.294%;验证性因子分析结果显示,χ^(2)/df=1.998,GFI=0.891,CFI=0.964,IFI=0.916,TLI=0.901,RMSEA=0.060。量表总的Cronbach′sα系数为0.906,各维度的Cronbach′sα系数为0.835~0.963;分半信度为0.904。结论编制的PICU转科患儿照顾者准备度量表信效度良好,可用于评估PICU住院患儿恰当转科时机及照顾者准备程度。

关键词：危重患儿儿童重症监护病房转科照顾者准备度量表编制信度效度过渡期护理

Synthesis,structures and photoluminescence of uranyl polyoxometalate clusters based on trilacunary[TeW_(9)O_(33)]^(8-)

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钨科技(英文) 2023年第2期5卷 254-260页

作者： Hai-Ying Wang Xiu-Ying zheng La-Sheng Long Lan-sun zheng Xiang-Jian Kong State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China

Synthesis of uranyl polyoxometalate clusters attract more attention but remain great ***,two uranyl polyoxometalate inorganic clusters of{Na_(6)(NH_(4))_(19)[(TeW_(9)O_(33))_(4)[TeO_(2)(OH)](UO_(2))4(H_(2)O)_(2)]·50H_(2)O}n(1,Te-U_(4))and(NH_(4))18{Na@[(TeW_(9)O_(32)OH)(TeW_(9)O_(33))_(2)[TeO(OH)][W_(3)O_(12)(μ_(3)-OH)](UO_(2))_(6)(μ_(2)-OH)_(2)H_(2)O]}·75H_(2)O(2,Te-U6)were prepared using trilacunary[α-B-TeW_(9)O_(33)]8-as inorganic *** analysis showed that compound 1 is a one-dimensional chain structure formed by tetrameric aggregates of[(α-B-TeW_(9)O_(33))_(4)(TeO_(2)(OH))(UO_(2))_(4)(H_(2)O)2]25-as nodes and Na+ions as *** anionic tetrameric aggregates in 1 is made of two sandwich-type dimers of[(TeW_(9)O_(33))_(2)(UO_(2))_(2)H_(2)O]12-bridged by a[TeO_(2)(OH)]-*** 2 is a triangular trimeric architecture templated by Na+*** solid-state luminescence emission spectra of compounds 1 and 2 show the characteristic peaks of uranyl *** 1 with one-dimensional chain structure exhibited a higher photoluminescence quantum yields(PLQY)than that of 2,due to the more rigidity of 1 reducing the nonradiative transitions.

关键词： Uranyl Polyoxometalate Cluster Lacunary Luminescence

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紫外光固化丙烯酸酯树脂的研究与应用进展

胶体与聚合物 2024年第1期42卷 46-50页

作者：胡益群邓华孙争光湖北三峡实验室湖北宜昌443000 湖北大学材料科学与工程学院武汉430062

UV光固化凭借其快速固化、无污染、低能耗等优势在3D打印、涂料等领域被广泛应用。丙烯酸酯类低聚物是目前用量最大、应用最广的自由基光固化低聚物,综述了丙烯酸酯类低聚物的研究进展,主要包括环氧丙烯酸酯、聚氨酯丙烯酸酯、聚酯丙烯... 详细信息

UV光固化凭借其快速固化、无污染、低能耗等优势在3D打印、涂料等领域被广泛应用。丙烯酸酯类低聚物是目前用量最大、应用最广的自由基光固化低聚物,综述了丙烯酸酯类低聚物的研究进展,主要包括环氧丙烯酸酯、聚氨酯丙烯酸酯、聚酯丙烯酸酯、聚酯丙烯酸酯四类,以及光固化树脂在3D打印、油墨、涂料、胶粘剂领域的应用进展。针对自由基光固化的不足对光固化树脂未来的研究进行了展望。

关键词：光固化丙烯酸酯 3D打印涂料

Synthesis,Characterization and Protonation Study of Novel Poly(thioether imide)s based on Aromatic Heterocyclic Diimide

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Journal of Wuhan University of Technology(Materials Science) 2013年第2期28卷 269-273页

作者：赵晓燕 WANG Chenyi ZHAO Xiaohua sun zheng College of Petrochemical Engineering Changzhou University Changzhou Expansion New Stuff Technology Co. Ltd School of Materials Science and Engineering Changzhou University

Novel poly（thioether imide）s were synthesized by 2,5-dimercapto-l,3,4-thiadiazole, and aromatic heterocyclic chlorodiimids through nucleophilic!substitution reaction as alkali catalysts were presented. The poly（thioether imide）s exhibited good thermal property. The glass transition temperatures of polymers were around 373 ℃, and 10% weight loss temperatures were in the range of 450-500 ℃ in nitrogen/air atmosphere. Meanwhile, the chloroform dilute solutions of these polYmers could show strong UV-vis absorption peaks at about 289 nm. After being protonated by inorganic acids （HC1）, the new shoulder absorption peaks were observed at 350 nm. The PL absorption bands of polymer solutions were in the region of 350-550 nm, which showed the green-yellow fluorescence.

关键词： aromatic heterocyclic chlorodiimide thermal stability fluorescence protonation

“三全育人”背景下医学生职业核心能力现状及培养路径探析

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卫生职业教育 2024年第14期42卷 103-106页

作者：石来敏张晴晴孙铮山东第一医科大学临床与基础医学院山东济南250117

目的调查医学生职业核心能力现状,分析其影响因素,探寻其培养路径。方法以山东省某高等医学院校临床医学本科生为研究对象,采用方便抽样法收集资料,采用医学生职业核心能力问卷等进行调查并分析数据。结果职业核心能力得分率为75.0%,是... 详细信息

目的调查医学生职业核心能力现状,分析其影响因素,探寻其培养路径。方法以山东省某高等医学院校临床医学本科生为研究对象,采用方便抽样法收集资料,采用医学生职业核心能力问卷等进行调查并分析数据。结果职业核心能力得分率为75.0%,是否独生子女、学习目标为职业核心能力的主要影响因素(P<0.05)。结论医学生职业核心能力得分率处于中等水平,应针对医学生教育教学现状,优化培养方案,创新职业能力培养方法,构建校企协同育人机制,将“三全育人”理念落地落实,促进医学生全面发展。

关键词： “三全育人” 医学生职业核心能力

维普期刊数据库博看期刊

Optically Stimulated Luminescence(OSL) Chronology of the Dehenglong Landslide from Longyang Gorge to Liujia Gorge along Upper Yellow River, China

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 242-250页

作者： GUO Xiaohua LAI Zhongping LU Yudong LI Xiaolin sun zheng Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education School of Environmental Science and Engineering Chang'an University School of Earth Sciences China University of Geosciences Key Laboratory of Environmental Geology of Qinghai Province Qinghai Provincial 906 Qinghai Institute of Geological Investigation

Giant landslides are common along the upper Yellow River from Longyang Gorge to Liujia Gorge, and some of them even blocked and dammed the upper Yellow River. Chronology is inevitable in studying the mechanism of giant landslides. Controversy exists about the chronology of those giant landslides, and some have not yet dated. The Dehenglong landslide is the largest one among them. In this study, OSL samples were collected from lacustrine silty sediments and loess directly overlying the landslide sediments, as well as fault sediments related to the landslide. This landslide yielded an age of 89 ±8 ka, which is identical with the fault age of 73 ±5 ka at two sigma errors. The agreement of a topographic analysis and the absolute age of landslides imply that the formation of the Dehenglong landslide is strongly correlated with the tectonic activity.

关键词： landslide OSL Upper Yellow River in China Qinghai-Tibetan Plateau