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Journal of Advanced Ceramics 2024年第6期13卷 789-799页

作者： Guangheng zhang Jinyu Shi Jie zhang jingyang Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Environmental barrier coatings(EBCs)with thermomechanical robustness against calcium–magnesium–aluminum–silicate(CMAS)deposits are in high *** aim of this work was to clarify the influence of Sc^(3+)on the crystallization behavior of Yb-based coatings against CMAS *** reaction products of solid solutions with compositions traversing the Sc_(2)O_(3)–Yb_(2)O_(3)system indicate that Sc^(3+)tends to form[BO_(6)]coordination polyhedra in the crystal structure to promote the formation of garnet and diopside,while Yb^(3+)occupies 7-,8-,and 9-coordinate sites to crystallize apatite and *** transformation of crystalline products from apatite/silicocarnotite to garnet/diopside greatly improves the efficiency of CMAS melt consumption and facilitates the prevention of its further penetration and *** on the commonality of cation occupancy in crystallography,an A(CaO+YbO_(1.5))–B(ScO_(1.5)+MgO+AlO_(1.5))–T(SiO_(2))pseudoternary phase diagram is established,which has great potential for describing phase equilibrium in coating-deposit systems and can provide guidance for the compositional design of corrosion-resistant coatings.

关键词： crystallization behavior cation partitioning scandium-ytterbium oxide(Sc_(x)Yb_(1−x))O_(1.5)solid solution calcium-magnesium-aluminum-silicate(CMAS)deposit pseudoternary phase diagram

Generating Baikal-GVD high energy cascade-like neutrino events with a GEANT4-based simulation toolkit

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Chinese Physics C 2024年第10期48卷 256-263页

作者： Zike Wang A.D.Avrorin zhen Cao Mingjun Chen Peiyuan Chu zh.-A.M.Dzhilkibaev Bo Gao Tianqi Huang Jiali Liu Ying Qi Xiaohao You D.N.Zaborov Key Laboratory of Particle Astrophysics Experimental Physics Division&Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China Institute for Nuclear Research of the Russian Academy of Sciences Moscow 117312Russia TIANFu Cosmic Ray Research Center Chengdu 610213China School of Science Tibet UniversityLhasa 850000China

using the GEANT4 and Cosmic Ray Monte Carlo(CRMC)software packages,we developed a new simulation toolkit for astrophysical neutrino *** configuring the Baikal-GVD detector and comparing the vertex position and direction of incident particles,as well as the channel-by-channel signals,to the events detected by Baikal-GVD,we successfully generated 13 high-energy cascade neutrino events with the *** analysis revealed a systematic offset between the reconstructed shower position and the true interaction position,with a distance close to the scale of the shower maximum of−0.54±1.29 *** achieved a good linear relationship between the photoelectron number of neutrino events obtained by simulation and the real data measured by *** simulation toolkit could serve as a reliable basis for studying the performance of astrophysical neutrino telescopes.

关键词： high-energy neutrino cascade event simulation Cherenkov

大气等离子喷涂Y_(3)Al_(5)O_(12)/Al_(2)O_(3)陶瓷涂层的CMAS腐蚀抗力

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无机材料学报 2024年第6期39卷 671-680,I0001,I0002页

作者：李捷罗志新崔阳张广珩孙鲁超王京阳中国科学院金属研究所沈阳110016 中国科学技术大学材料科学与工程学院沈阳110016

探索能够有效抵抗1300℃及以上温度钙镁铝硅酸盐(Calcium-Magnesium-Aluminum-Silicate,CMAS)腐蚀的新材料是近年来先进航空发动机用环境障涂层研究的重点任务。本工作围绕具有超强CMAS腐蚀抗力的YAG(Y_(3)Al_(5)O_(12))/Al_(2)O_(3)体系,采用大气等离子喷涂(Atmospheric Plasma Spraying,APS)技术制备了具有共晶成分的YAG/Al_(2)O_(3)涂层。通过在1100、1300和1500℃对制备态涂层进行热处理,获得了具有不同微观结构的YAG/Al_(2)O_(3)涂层。利用不同表征手段研究了YAG/Al_(2)O_(3)涂层抵抗1300℃CMAS腐蚀的性能及微观结构对涂层腐蚀抗性的影响。研究结果发现,经不同温度热处理的YAG/Al_(2)O_(3)涂层与CMAS的反应产物均为石榴石结构固溶体、CaAl_(2)Si_(2)O_(8)和Ca_(2)MgSi_(2)O_(7)。腐蚀机制研究发现,1100℃热处理YAG/Al_(2)O_(3)涂层与CMAS反应界面的近连续分布石榴石固溶体层可有效阻隔CMAS腐蚀元素的扩散;1500℃热处理YAG/Al_(2)O_(3)涂层晶粒尺寸的增加及晶界数量的减少可降低涂层材料在CMAS中的溶解速率,二者均可通过影响腐蚀过程中的离子传输速率而影响各生成物的竞争析出,进而提升涂层的CMAS腐蚀抗力。本工作为YAG/Al_(2)O_(3)涂层热处理工艺优化提供了借鉴,并为通过微观结构优化调控YAG/Al_(2)O_(3)涂层的CMAS腐蚀抗力提供了新思路。

关键词： YAG(Y_(3)Al_(5)O_(12))/Al_(2)O_(3) 大气等离子喷涂环境障涂层 CMAS腐蚀抗力晶界腐蚀热处理温度

吉林敦化地区万宝岩组碎屑锆石u-Pb-Hf同位素组成:对区域构造演化的制约

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吉林大学学报（地球科学版） 2024年第4期54卷 1264-1279页

作者：关子成裴福萍魏敬洋李鹏屹吉林大学地球科学学院长春130061

为制约古亚洲洋在吉林东部地区的最终闭合时间,本文选取吉林省敦化地区万宝岩组变质粉砂岩为研究对象,开展系统的碎屑锆石微量元素组成和u-Pb-Hf同位素研究,确定了万宝岩组的沉积时限和物源区特征,并通过碎屑锆石微量元素获得晚古生代... 详细信息

为制约古亚洲洋在吉林东部地区的最终闭合时间,本文选取吉林省敦化地区万宝岩组变质粉砂岩为研究对象,开展系统的碎屑锆石微量元素组成和u-Pb-Hf同位素研究,确定了万宝岩组的沉积时限和物源区特征,并通过碎屑锆石微量元素获得晚古生代地壳厚度的变化规律,探讨了华北板块北缘东段晚古生代的构造演化历史。万宝岩组由互层的大理岩、变质粉砂岩和变质细砂岩组成,碎屑锆石定年结果显示,万宝岩组最年轻峰值年龄约为316 Ma,此外还存在355、398、1 842和2 360 Ma的峰值年龄。其中,古生代碎屑锆石(409~312 Ma)以具有负的εHf(t)值(-15.32~-1.60)及新太古代—古元古代的TDM2年龄(2 293~1 480 Ma)为特征,侵入万宝岩组闪长岩体的时期为276 Ma。综合研究认为,敦化地区万宝岩组沉积时限为312~276 Ma,即早二叠世时期,其沉积时限和岩石组合特征可与延边地区的庙岭组相对比。万宝岩组中的古生代碎屑锆石来自华北板块太古宙—古元古代结晶基底物质的部分熔融。结合其中古元古代碎屑锆石(62.9%)的大量出现,暗示敦化地区或/和附近地区存在华北板块前寒武纪的结晶基底。通过地壳厚度计算表明,敦化地区和内蒙古地区晚古生代的地壳厚度变化趋势一致,说明二者晚古生代的演化历史趋于同步。约245 Ma地壳厚度达到最大(80 km),暗示了古亚洲洋的最终闭合。

关键词：华北板块北缘晚古生代碎屑锆石 u-Pb-Hf同位素地壳厚度万宝岩组古亚洲洋

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整体叶轮圆角立铣刀五轴u摆线剥铣轨迹规划

机械工程学报 2024年第7期60卷 212-223页

作者：李佳男魏兆成冯景洋王学勤大连理工大学高性能精密制造全国重点实验室大连116024

摆线剥铣工艺具有加工效率高、切削力小、刀具耐用度高的优点,然而由于缺乏五轴剥铣加工的轨迹规划方法,导致高效剥铣技术难以应用于整体叶轮加工。针对该问题提出一种整体叶轮圆角立铣刀五轴u摆线剥铣的轨迹规划方法。安排系列切削力实... 详细信息

摆线剥铣工艺具有加工效率高、切削力小、刀具耐用度高的优点,然而由于缺乏五轴剥铣加工的轨迹规划方法,导致高效剥铣技术难以应用于整体叶轮加工。针对该问题提出一种整体叶轮圆角立铣刀五轴u摆线剥铣的轨迹规划方法。安排系列切削力实验,验证圆角立铣刀u摆线剥铣相较于现有球头立铣刀u摆线剥铣的加工优势。在此基础上建立叶轮模型降维映射关系,将三维叶根曲线映射到二维平面上,作为边界规划降维刀触点,基于刀触点与流道两侧叶片的比例关系计算刀轴矢量和刀位点,实现圆角立铣刀五轴u摆线剥铣轨迹初步规划。计算叶根过渡面上点到刀具特征面的距离,建立圆角立铣刀与叶根过渡面的干涉判据模型。使用投影法将干涉的叶根过渡面点集向刀轴矢量投影,计算刀具的最大轴向干涉量,从而优化刀位点排除叶根过渡面干涉。最后应用叶轮加工仿真验证五轴u摆线轨迹方法的有效性,结果表明五轴u摆线轨迹能够顺利实现整体叶轮圆角立铣刀剥铣加工,加工过程中无过切干涉,残留材料均匀,可为叶轮后续加工提供良好的基础。

关键词：摆线加工剥铣刀具轨迹叶根干涉

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基于降维映射的五轴u摆线铣削刀轨生成研究

机械工程学报 2024年第5期60卷 362-377页

作者：冯景洋魏兆成王敏杰舒鑫张勇雍建华大连理工大学精密与特种加工教育部重点实验室大连116024 沈阳鼓风机集团股份有限公司沈阳110869

刀具轨迹生成作为数控加工的重要组成部分,是包含铣削方式、刀具工件结构以及加工余量等多因素在内的复杂体系。u摆线铣削是在摆线铣削基础上结合侧铣加工特性的走刀策略,能够以大轴向切深完成粗加工,平稳切入切出的走刀形式可以有效平... 详细信息

刀具轨迹生成作为数控加工的重要组成部分,是包含铣削方式、刀具工件结构以及加工余量等多因素在内的复杂体系。u摆线铣削是在摆线铣削基础上结合侧铣加工特性的走刀策略,能够以大轴向切深完成粗加工,平稳切入切出的走刀形式可以有效平滑切削力,分散局部载荷。以整体叶轮流道为目标,提出一种基于降维映射的u摆线铣削刀轨生成方法。建立u摆线铣削几何模型,定义摆线表征参数并给出摆线残留量计算方法。根据刀具运动规律将轨迹离散为系列微元,以刀具与前一刀轨迹的交点为划分依据将轨迹划分为多个区域,分别获得相应摆线位置角下刀-工包角计算方法。安排了系列实验,验证了u摆线铣削在切削力及刀具磨损方面的加工优势。结合u摆线铣削特征建立铣削边界预处理方法,考虑到三维空间刀具轨迹计算复杂,定义空间几何域及降维参数域,在此基础上给出平铺微弧的降维映射方法并分别在不同摆线区间计算降维轨迹。为获得无干涉u摆线铣削刀轴矢量,借助等参数方程建立双向比例域映射算法,通过求解系列偏转角度实现任意矢量逆映射。最后将轨迹矩阵编码为通用机床语言,通过仿真算例及铣削实验验证刀轨生成方法的可行性。

关键词： u摆线铣削降维映射刀-工包角五轴铣削刀具轨迹

高熵稀土单硅酸盐环境障涂层局域结构的原子对分布函数解析

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金属学报 2024年第8期60卷 1130-1140页

作者：王浩宇吕熙睿陈琦熊瑛罗志新张洁王京阳中国科学院金属研究所沈阳材料科学国家实验室沈阳110016 中国科学技术大学材料科学与工程学院合肥230000 中国航发沈阳黎明航空发动机有限责任公司沈阳110043

调控稀土单硅酸盐(RE_(2)SiO_(5))环境障涂层热膨胀系数,优化其与碳化硅纤维增强碳化硅(SiC_(f)/SiC)陶瓷基复合材料基体热膨胀系数匹配性,是其应用于高推比航空发动机的关键。本工作基于RE_(2)SiO_(5)/Yb_(2)Si_(2)O_(7)/Si三层结构涂... 详细信息

调控稀土单硅酸盐(RE_(2)SiO_(5))环境障涂层热膨胀系数,优化其与碳化硅纤维增强碳化硅(SiC_(f)/SiC)陶瓷基复合材料基体热膨胀系数匹配性,是其应用于高推比航空发动机的关键。本工作基于RE_(2)SiO_(5)/Yb_(2)Si_(2)O_(7)/Si三层结构涂层体系,对比研究了采用与基体热膨胀系数匹配优的(Y_(1/4)Ho_(1/4)Er_(1/4)Yb_(1/4))_(2)SiO_(5)面层与典型Yb_(2)SiO_(5)面层涂层体系的抗热冲击性能,发现Yb_(2)SiO_(5)面层热膨胀系数偏大造成的应力累积,是导致三层结构涂层失效的主要原因。依据中子衍射数据,分析中子对分布函数,对2种单硅酸盐局域结构特征进行解析。结果表明,高熵稀土单硅酸盐中多种稀土元素协同作用,降低了[ORE_(4)]四面体畸变程度,表现为热膨胀系数减小。提出通过合理选择稀土元素组合,扰动[ORE_(4)]局域结构畸变,有望实现稀土单硅酸盐热膨胀系数的定向调控。

关键词：中子衍射原子对分布函数稀土硅酸盐环境障涂层燃气热冲击

Accelerating the design of multicomponent rare earth silicates for SiC_(f)/SiC CMC by combinatorial material chip design and high throughput screening

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Journal of Materials Science & Technology 2023年第19期150卷 96-103页

作者： Xirui Lv Yiming Lei zhao zhang Jie zhang jingyang Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

High throughput experimentation is employed to establish a ternary system with the compositional range of 30.8 mol.%-75.7 mol.%SiO_(2),16.6 mol.%-61.7 mol.%Yb_(2)O_(3),and 6.3 mol.%-4.1 moll.%Ho_(2)O_(3) through co-sputtering deposition on one combinatorial material *** their application in advanced SiC_(f)/SiC CMC,the phase composition and mechanical properties of samples with various RE/Si ratios and Yb/Ho ratios are comprehensively *** stability and thermal expansion compatibility between SiC and RE silicates with different compositions are also *** materials for the application of environmental barrier coating and interphase for SiC_(f)/SiC CMC are screened respectively according to the above trends and *** work is a case study to establish a composition-property library for RE_(2)O_(3)-SiO_(2) *** is inspired more complicated multicomponent RE silicates could be prepared and characterized by high throughput experimentation,accelerating the design and screening of promising optimal candidates.

关键词： High throughput experimentation RE silicates Phase stability Mechanical properties

Genesis and uranium Sources of Leucogranite-hosted uranium Deposits in the Gaudeanmus Area, Central Damara Belt, Namibia: Study of Element and Nd Isotope Geochemistry

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2126-2137页

作者： FAN Honghai CHEN Jinyong WANG Shengyun zhAO jingyang Gu Dazhao MENG Yanning Beijing Research Institute of uranium Geology Key Laboratory of uranium Resource Exploration and Evaluation Technology CNNC Department of Earth Sciences and State Key Lab of Mineral Deposit Research Nanjing University

This paper presents a systematic study of major and trace elements and Sm-Nd isotopes in leucogranites closely related to uranium mineralization in the Gaudeanmus area, Namibia. The results illustrate that the uraniferous leucogranites possess high SiO2 （68.8wt%-76.0wt%, average 73.1wt%） and K （4.05wt%-7.78wt%, average 5.94wt%） contents, and are sub-alkaline and metaluminous to weakly peraluminous, as reflected by A/CNK values of 0.96-1.07 with an average of 1.01. The leucogranites are rich in light rare earth elements （LREE/HREE = 2.53-7.71; （La/Yb）s = 2.14-10.40）, have moderate Eu depletion and high Rb/Sr ratios （2.03-5.50 with an average of 4.36）; meanwhile, they are enriched in Rb, K, Th, u and Pb, and depleted in Ba, Nb, Ta, and Sr. The tNd（t） values of uraninites range from -14.8 to -16.5, and the two-stage Nd model ages are 2.43-2.56 Ga. Detailed elemental and Sm-Nd isotopic geochemical characteristics suggest that the leucogranites were formed in a post- orogenic extensional environment. The u-rich pre-Damara basement was the main source of uranium during the primary mineralization event, which is disseminated in leucogranites, whereas the uranium mineralization in veins possibly resulted from remobilization of the primary uranium minerals.

关键词： uranium source of uranium Nd isotopes leucogranites Gaudeanmus Damara Belt

Analytical and numerical modeling of optical second harmonic generation in anisotropic crystals using #SHAARP package

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npj Computational Materials 2022年第1期8卷 2343-2354页

作者： Rui Zu Bo Wang jingyang He Jian-Jun Wang Lincoln Weber Long-Qing Chen Venkatraman Gopalan Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA Materials Science Division Lawrence Livermore National LaboratoryLivermoreUSA Department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity ParkPA16802USA Department of Mathematics The Pennsylvania State UniversityUniversity ParkPA16802USA Department of Physics Pennsylvania State UniversityUniversity ParkPA16802USA

Electric-dipole optical second harmonic generation(SHG)is a second-order nonlinear process that is widely used as a sensitive probe to detect broken inversion symmetry and local polar *** modeling of the SHG polarimetry of a nonlinear optical material is essential to extract its point group symmetry and the absolute nonlinear *** literature on SHG analysis involves numerous approximations and a wide range of(in)*** have developed an open-source package called the Second Harmonic Analysis of Anisotropic Rotational Polarimetry(♯***)which derives analytical and numerical solutions of reflection SHG polarimetry from a single interface(.si)for bulk homogeneous crystals with arbitrary symmetry group,arbitrary crystal orientation,complex and anisotropic linear dielectric tensor with frequency dispersion,a general SHG tensor and arbitrary light polarization.♯*** enables accurate modeling of polarimetry measurements in reflection geometry from highly absorbing crystals or wedge-shaped transparent *** package is extendable to multiple interfaces.

关键词： arbitrary symmetry harmonic