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Effect of Na^(+)and Sr^(2+)Substitution on the Formation of the Oxygen Vacancies in Y_(3)Al_(2)Ga_(3)O_(12):Ce^(3+)Phosphor

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1221-1230页

作者： YANG Ting jiang hongyi DONG Ye GAO Shuai LIU Shuning School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The low-valence cations Na^(+)and Sr^(2+)were selected as the co-dopants to increase the vacancies concentration in the Y_(2.982)Ce_(0.018)Al_(2)Ga_(3)O_(12)*** successful incorporation of Na^(+)and Sr^(2+)was confirmed by the X-Ray Difiraction(XRD)*** the samples show 5d-4f green persistent luminescence of Ce^(3+)after 450 nm *** decay curves demonstrate that the persistent luminescence is efiectively enhanced with Na+and Sr2+*** thermoluminescence glow curves also show not only does the trap concentration increase,but also the distribution of trap depths is *** addition,the air-and H_(2)/Ar-annealing treatments were conducted on every as-made *** experimental results prove that the increased traps after the Na^(+)/Sr^(2+)doping are mainly attributed to the oxygen vacancies,and the traps have a continuous and broad distribution of trap *** hope this work could give new inspiration for designing a high-performance persistent phosphor.

关键词： persistent luminescence YAGG Na^(+) Sr^(2+) oxygen vacancy charge compensation solidstate reaction

Facile Preparation of Al2O3 Hollow Microspheres Via a Urea-mediated Precipitation Process

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 579-586页

作者： XU Dong jiang hongyi School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Optical Fiber and Cable Manufacture Technology Wuhan430070China Yangtze Optical Fibre and Cable Joint Stock Limited Company Wuhan430070China

Al2 O3 hollow microspheres without noticeable aggregation have been prepared via a facile templating route with urea-mediated precipitation. The precipitation process is different from the surfaceadsorption method which is confined to the adsorption capacity of the template surface. TEM and SEM images indicate that most of these Al2 O3 hollow microspheres with shell thickness of tens of nanometers and diameters in a narrow range of 100-200 nm consist of a shell of closely packed nanoparticles. The optimal amount of H2 O and EtOH are 40 and 120 m L, respectively. The specific surface area, average pore size and pore volume of the Al2 O3 hollow microspheres（calcinated at 600 ℃） are 328.52 m2/g, 17.496 nm and 1.985 cm3/g, respectively. As the calcination temperature increases from 600 to 1 100 ℃, the phase composition changes from γ-Al2 O3 to θ-Al2 O3 and a-Al2 O3, and the surface morphology appears to change from a relatively rough surface formed by nanoparticles to a smooth surface formed by lamellar, which lead to the closure of pore channels and the reduction of specific surface.

关键词： Al2O3 hollow microspheres precipitation nanoparticles specific surface area

Ultra-lightweight ceramic scaffolds with simultaneous improvement of pore interconnectivity and mechanical strength

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Journal of Materials Science & Technology 2023年第6期137卷 247-258页

作者： Ye Dong Annan Chen Ting Yang Shuai Gao Shuning Liu hongyi jiang Yusheng Shi Chenglong Hu School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Engineering Research Center of Ceramic Materials for Additive Manufacturing Ministry of EducationWuhan 430074China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The high porosity and interconnectivity of scaffolds are critical for nutrient transmission in bone tis-sue engineering but usually lead to poor mechanical ***,a novel method that combines acid etching(AE)with selective laser sintering(SLS)and reaction bonding(RB)of Al particles is pro-posed to realize highly improved porosity,interconnectivity,mechanical strength,and in vitro bioactivity in 3D Al_(2)O_(3) *** controlling the oxidation and etching behaviors of Al particles,a tunable hol-low spherical feature can be obtained,which brings about the distinction in compressive response and fracture *** prevention of microcrack propagation on the in situ formed hollow spheres results in unique near elastic buckling rather than traditional brittle fracture,allowing an unparalleled compressive strength of 3.72±0.17 MPa at a high porosity of 87.7%±0.4%and pore interconnectivity of 94.7%±0.4%.Furthermore,scaffolds with an optimized pore structure and superhydrophilic surface show excellent cell proliferation and adhesion *** findings offer a promising strategy for the coexistence of out-standing mechanical and biological properties,with great potential for tissue engineering applications.

关键词： Ceramic scaffolds Selective laser sintering Acid etching Hollow spherical feature Mechanical strength In vitro bioactivity

Microstructure evolution and mechanical properties of Al_(2)O_(3)foams via laser powder bed fusion from Al particles

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Advanced Powder Materials

Advanced Powder Materials 2023年第4期2卷 114-123页

作者： Ye Dong Annan Chen Ting Yang Shuai Gao Shuning Liu Bingjian Guo hongyi jiang Yusheng Shi Chunze Yan School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Engineering Research Center of Ceramic Materials for Additive Manufacturing Ministry of EducationWuhan 430074China Centre for Advanced Structural Materials Department of Mechanical EngineeringCity University of Hong KongHong KongChina

Laser powder bed fusion(LPBF)combined with reaction bonding(RB)of Al particles is an effective method for preparing high-performance 3D Al_(2)O_(3) ceramic ***,the indistinct microstructure evolution hinders the regulation of pore features and the improvement of synthetic ***,the microstructure evolution of the Al_(2)O_(3) ceramic foams during the LPBF/RB process is clariﬁed by various characterization methods,and the corresponding mechanical property modulation is realized by optimizing LPBF parameters,organic binder(E12 epoxy resin)content,heating rate,sintering time,and coral-like Al_(2)O_(3) *** expansion from Al_(2)O_(3) outward growth and Al granule precipitation counteracts the shrinkage from E12 decomposition and Al_(2)O_(3) sintering,resulting in an ultra-low shrinkage of 0.94%–3.01%.The pore structures of particle packing pores,hollow spheres,and microporous structures allow a tunable porosity of 52.6%–73.7%.The in-situ formation of multi-scale features including hollow spheres,ﬂaky grains,whiskers,nanoﬁbers,and bond bridges brings about a remarkably high bending strength of 6.5–38.3 ***ﬁndings reveal the relationship between microstructure evolution and property optimization of high-performance ceramic foams,with potential signiﬁcance for microstructure design and practical application.

关键词： Al_(2)O_(3)ceramic foams Laser powder bed fusion Reaction bonding Microstructure evolution Mechanical property modulation

Preparation and Absorption/Desorption Performance of Gypsum-based Humidity Controlling Materials

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 684-686页

作者：姜洪义 School of Materials Science and Engineering Wuhan University of Technology

Absorption/desorption properties of some humidity controlling materials which contain gypsum as basic cement materials and activated Sepiolite powder as humidity controlling media were tested. The kinetics curve of moisture adsorption/desorption were drawn and humidity controlling performance in nature environment was verified. The experimental results show that moisture absorption/desorption rates are increased, and the speed is also accelerated. These materials, which can adjust environmental humidity effectively, are new ones with good humidity controlling performance.

关键词： activated Sepiolite gypsum-composites humidity controlling performance

从巴基斯坦“新民族”现象解读跨界民族身份认同

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国际展望 2023年第2期15卷 102-115,161页

作者：姜宏毅上海外国语大学国际关系与公共事务学院上海201620

巴基斯坦“新民族”的形成与阿富汗难民问题息息相关。随着阿富汗政局逐渐平稳,陆续有难民回归,但是仍有大量人员不愿意离开巴基斯坦。其主要是因为阿富汗的条件无法完全保证和平生活,以及缺乏经济机会。阿富汗难民在巴基斯坦生活了二... 详细信息

巴基斯坦“新民族”的形成与阿富汗难民问题息息相关。随着阿富汗政局逐渐平稳,陆续有难民回归,但是仍有大量人员不愿意离开巴基斯坦。其主要是因为阿富汗的条件无法完全保证和平生活,以及缺乏经济机会。阿富汗难民在巴基斯坦生活了二十多年,新一代的阿富汗人在一个全新的环境中长大,特别是在巴基斯坦出生和长大的孩子,他们认为自己更多的是巴基斯坦社会的一部分。巴基斯坦“新民族”逐渐形成。“新民族”的诞生也引发了其他许多社会问题,尤其是难民们对阿巴两国的国家以及民族身份认同等问题。跨界民族的身份认同问题十分敏感,极易引发跨国安全问题,是对中南亚地区安全的极大隐患,其唯一可行的解决之道,只能是国际社会各方共同努力,减少难民数量,帮助阿富汗尽快实现战后重建工作,维护好良性的国内生存环境,以此来实现难民的遣返,进而在最大程度上实现中南亚地区的和平与稳定。

关键词：普什图人新民族身份认同跨界民族中南亚地区

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高温固相法制备硅酸盐长余辉发光材料

硅酸盐学报 2006年第9期34卷 1154-1157页

作者：姜洪义徐博武汉理工大学材料科学与工程学院硅酸盐材料工程教育部重点实验室武汉430070

使用碳还原法和气体还原法制备硅酸盐长余辉材料,探讨了不同铕、镝含量,不同硼含量,烧成方式和二氧化硅粒径对样品余辉性能的影响。结果表明:硅酸盐长余辉材料中硼含量的提高可有效降低烧成温度,但发光性能也随之下降。不同铕、镝含量... 详细信息

使用碳还原法和气体还原法制备硅酸盐长余辉材料,探讨了不同铕、镝含量,不同硼含量,烧成方式和二氧化硅粒径对样品余辉性能的影响。结果表明:硅酸盐长余辉材料中硼含量的提高可有效降低烧成温度,但发光性能也随之下降。不同铕、镝含量的样品对应不同的适宜硼含量。选择适当纯度和颗粒组成的SiO2有利于改善硅酸盐长余辉材料的结构和发光性能。气体还原法所得硅酸盐长余辉材料的发光性能优于碳粉还原法。组成为Sr1.97MgSi2O7:(Eu0.005,Dy0.025,B0.15)的样品有较好的发光性能,余辉时间超过10h。

关键词：硅酸盐长余辉固相反应发光材料

行政国家:基于马克思国家相对独立性理论的分析

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理论月刊 2011年第5期 34-36页

作者：江红义海南大学政治与公共管理学院海南海口570228

马克思的国家相对独立性理论认为,国家来源于社会并作为凌驾于社会之上的公共权力共同决定了国家必然具有相对于社会的独立性;国家所具有的独立性,是相对于包括经济上的统治阶级在内的社会一切阶级而言的;国家形式决定了国家相对独立性... 详细信息

马克思的国家相对独立性理论认为,国家来源于社会并作为凌驾于社会之上的公共权力共同决定了国家必然具有相对于社会的独立性;国家所具有的独立性,是相对于包括经济上的统治阶级在内的社会一切阶级而言的;国家形式决定了国家相对独立性的程度。一般而言,行政国家比议会至上的国家具有更高程度的独立性。就行政国家而言,不同的国家形式对于行政机关及其官僚所执掌的公共权力的"异化"倾向的制约程度也不相同,从而使这些不同形式的行政国家表现出不同程度的独立性。但是,任何国家都不具有绝对的独立性,因为国家终究要受到社会的制约。

关键词：行政国家马克思国家相对独立性官僚

调节定向和调节匹配对情感预测中影响偏差的影响

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心理学报 2017年第12期49卷 1537-1547页

作者：耿晓伟姜宏艺鲁东大学教育科学学院烟台264011

现实生活中,人们在决策前需要对决策可能带来的结果进行预测。人们往往会高估未来事件对其情绪的影响,这被称为影响偏差。本研究从自我调节理论的视角出发,考察了调节定向和调节匹配对情感预测中影响偏差的影响。实验1和实验2分别在积... 详细信息

现实生活中,人们在决策前需要对决策可能带来的结果进行预测。人们往往会高估未来事件对其情绪的影响,这被称为影响偏差。本研究从自我调节理论的视角出发,考察了调节定向和调节匹配对情感预测中影响偏差的影响。实验1和实验2分别在积极和消极情景中考察了调节定向对情感预测偏差的影响;实验3和实验4分别在消极和积极情景中考察了调节匹配对情感预测偏差的影响。结果发现:(1)在对积极情感的预测中,促进定向个体比防御定向个体出现更大的影响偏差;在对消极情感的预测中,防御定向个体比促进定向个体出现更大的影响偏差。(2)调节匹配比调节不匹配条件下,个体会出现更大的影响偏差。因此,情感预测中的影响偏差是个体实现目标的一种自我调节策略,会受到调节定向和调节匹配的影响。

关键词：调节定向调节匹配情感预测影响偏差