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Cr^(3+) activated Na_(3)RESi_(3)O_9(RE=Y,Lu,Sc) silicate broadband near-infrared phosphors for luminescence towards NIR-Ⅱ region via a multi-site occupancy strategy

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Journal of Rare Earths 2024年第8期42卷 1447-1457,I0002页

作者： Jiantong wang changshuai Gong Sihan Yang Qi Zhu Xuejiao wang Ji-Guang Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou121007China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Electronic and Optical Materials National Institute for Materials ScienceTsukubaIbaraki 305-0044Japan

Phosphor-converted near-infrared light-emitting diodes(NIR pc-LEDs) are finding applications in various fields including food quality analysis,biomedical imaging,night vision,and *** crucial factor in the development of NIR pc-LEDs devices lies in the advancement of high-performance broadband NIR phosphors,In this work,novel Cr^(3+)-activated silicate phosphors NaRESi_(3)O_(9)(RE=Y,Lu,Sc) are *** silicate has a special 3D network structure in which RE has four different sites,forming four octahedrons and providing suitable occupation sites for Cr^(3+).The phosphors demonstrate a wide emission spectrum ranging from 750 to 1450 nm when excited by light at 468 *** full width at half maximum(FWHM),which benefits from the presence of Cr^(3+)ions occupying multiple sites,is measured to be 203 ***,the strongest emission peak is observed at a longer wavelength of 984 nm compared to most other systems activated by Cr^(3+).The Na_(3)ScSi_(3)O_(9) lattice provides a weak crystal field(Dq/B=1.97) and weak phonon-photon coupling for Cr^(3+),and the integrated emission intensity of Na_(3)ScSi_(3)O_(9):0,03Cr^(3+)is 4.66 times stronger than that of Na_(3)YSi_(3)O_(9):0.03Cr^(3+).

关键词： Rare earths Broadband near-infrared Silicate Photoluminescence Cr^(3+)

Microstructural evolution and its influence on the impact toughness of GH984G alloy during long-term thermal exposure

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Journal of Materials Science & Technology 2021年第1期60卷 61-69页

作者： Yunsheng Wu Xuezhi Qin changshuai wang Lanzhang Zhou Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

The microstructure evolution and its effect on the impact toughness of a new Ni-Fe based alloy GH984 G,used in 700℃ ultra-super critical coal-fired power plant,were investigated during thermal exposure at 650℃-750℃ for up to 10,000 *** results show that the impact toughness at room tempe rature drops rapidly at the early stage during thermal exposure at 700℃ and then has no significant change even if after exposure for 10,000 *** significant decline of the impact toughness is attributed to the coarsening of M_(23)C_(6) carbides at grain boundaries,which weakens the grain boundary strength and leads to the aging-induced grain boundary *** M_(23)C_(6) carbides have almost no change with further thermal exposure and the impact toughness also remains ***,the impact toughness rises with the increase of thermal exposure *** size of γ' after thermal exposure at 750℃ for10,000 h is much bigger than that at 650℃ and 700℃ for 10,000 *** fore,the intragranular strength decreases significantly due to the transformation of the interaction between γ' and dislocation from stro ngly coupled dislocation shearing to Orowan *** plastic deformation occurs within grains after thermal exposure at 750℃ for 10,000 h,which increases the impact toughness.

关键词： Ni-Fe based alloy GH984G Long-term thermal exposure Microstructure evolution Impact toughness

Effect of Melt Superheating Treatment on Directional Solidification Interface Morphology of Multi-component Alloy

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Journal of Materials Science & Technology 2011年第7期27卷 668-672页

作者： changshuai wang Jun Zhang Lin Liu Hengzhi Fu State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi an 710072 China

The influence of melt superheating treatment on the solid/liquid （S/L） interface morphology of directionally solidified Ni-based superalloy DZ125 is investigated to elucidate the relationship between melt characteristic and S/L interface stability. The results indicate that the interface morphology is not only related to the withdrawal velocity （R） but also to the melt superheating temperature （Ts） when the thermal gradient of solidification interface remains constant for different Ts with appropriate superheating treatment regulation. The interface morphology changes from cell to plane at R of 1.1 μm/s when Ts increases from 1500°C to 1650°C, and maintains plane with further elevated Ts of 1750°C. However, the interface morphology changes from coarse dendrite to cell and then to cellular dendrite at R of 2.25 μm/s when Ts increases from 1500°C to 1650°C and then to 1750°C. It is proved that the solidification onset temperature and the solidification interval undergo the nonlinear variation when Ts increases from 1500°C to 1680°C, and the turning point is 1650°C at which the solidification onset temperature and the solidification interval are all minimum. This indicates that the melt superheating treatment enhances the solidification interface stability and has important effect on the solidification characteristics.

关键词： Melt superheating treatment Directional solidification interface morphology Solidification characteristics Multi-component alloy

Thermal Stability of a New Ni-Fe-Cr Base Alloy with Different Ti/Al Ratios

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Journal of Materials Science & Technology 2015年第2期31卷 135-142页

作者： changshuai wang Tingting wang Meilin Tan Yongan Guo Jianting Guo Lanzhang Zhou Institute of Metal Research Chinese Academy of Sciences

Influence of Ti/Al ratios on the thermal stability of a new low cost Ni-Fe-Cr base wrought alloy,designed for application at 700℃ in advanced ultra-supercritical coal-fired power plants(700℃A-USC),was investigated both experimentally and thermodynamically. After standard heat treatment,the alloys with different Ti/Al ratios had the same microstructural characteristics. However,compared with the alloys with high Ti/Al ratio,the low Ti/Al ratio can increase the γ’-solvus temperature,decrease γ’ coarsening rate and reduce the temperature range of η phase precipitation. For the alloys with low Ti/Al ratio,the yield strength has no obvious decrease during long-term thermal exposure at 700 and 750℃,but after thermal exposure at 750℃ for 5000 h,the yield strength of the alloys with high Ti/Al ratio obviously decreases due to the η phase precipitation. The influence of h phase on mechanical properties is related with its size. When the h phase is small,it has no obvious influence on mechanical properties,but h phase becomes the crack initiation site with the further growth of η phase. It can be concluded that the decrease in Ti/Al ratio can improve the thermal stability to meet the requirement of 700℃ A-USC coal-fired power plants.

关键词： 700℃ A-USC Ni-Fe-Cr base alloy Thermal stability η

Correlation Between Phase Stability and Tensile Properties of the Ni-Based Superalloy MAR-M247

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Acta Metallurgica Sinica(English Letters) 2021年第6期34卷 872-884页

作者： Linxu Li Xiufang Gong changshuai wang Yunsheng Wu Hongyao Yu Haijun Su Lanzhang Zhou State Key Laboratory of Long-Life High Temperature Materials Dong Fang Turbine Co.LtdDeyang 618000China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Beijing Key Laboratory of Advanced High Temperature Materials Beijing 100081China Beijing CISRI-GAONA Materials and Technology CO. LTDBeijing 100081China

Phase stability and its effect on tensile properties of MAR-M247 alloy have been investigated during thermal exposure at 800–900°C for up to 10,000 *** investigations reveal that the larger secondaryγ′phase has no obvious growth,but the smaller tertiaryγ′phase obviously coarsens and the coalescence occurs during thermal exposure at 850°C and below.γ′coarsening behavior is consistent with the description of Ostwald ripening theory beforeγ′***-rich blocky MC carbide shows excellent thermal stability,but Ta-rich script-type MC carbide gradually degenerates via reaction,MC+γ→M_(23)C_(6)+γ′and finally formsγ film around MC and M_(23)C_(6) *** increasing thermal exposure time,the tensile strength *** ductility first increases and then decreases during exposure at 800°C,but it decreases continuously at 900°*** addition,the ductility keeps almost constant when the exposure time is longer than 5000 h.

关键词： Ni-based superalloy Phase stability Tensile properties Fractural behavior

A Revised Satellite Cloud-Derived Wind Inversion Algorithm Based on Computer Cluster

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Computers, Materials & Continua 2020年第7期64卷 373-388页

作者： Lili He Zhiwei Cai Dantong Ouyang changshuai wang Yu Jiang Chong wang Hongtao Bai College of Computer Science and Technology Jilin UniversityChangchun130012China Symbol Computation and Knowledge Engineer of Ministry of Education Jilin UniversityChangchun130012China Department of Engineering Mechanics State Marine Technical University of St.PetersburgSt.Petersburg190008Russia

In view of the satellite cloud-derived wind inversion has the characteristics of large scale,intensive computing and time-consuming serial inversion algorithm is very difficult to break through the bottleneck of *** proposed a parallel acceleration scheme of cloud-derived wind inversion algorithm based on MPI cluster parallel technique in this *** divide-and-conquer idea,assigning winds vector inversion tasks to each computing unit,is identified according to a certain *** computing unit executes the assigned tasks in parallel,namely divide-and-rule the inversion task,so as to reduce the efficiency bottleneck of long inversion time caused by serial time *** the scheme of parallel acceleration based on MPI cluster,an algorithm based on performance prediction is proposed to effectively implement load balance of MPI *** the comparative analysis of experiment data using the parallel scheme of this parallel technology framework,it shows that this parallel technology has a certain acceleration effect on the cloud-derived wind inversion *** speedup of the MPI-based parallel algorithm reaches 14.96,which achieved the expected *** the same time,this paper also proposes an efficiency optimization algorithm for cloud-derived wind *** the case that the inversion of wind vector accuracy loss is minimal,the optimized algorithm execution time can be up to 13 times faster.

关键词： Cloud-derived wind wind vector inversion parallel computing MPI speedup ratio

多分支废弃油井层温衰减规律及注入参数对注采性能的影响

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天然气工业 2024年第2期44卷 178-187页

作者：石昌帅王成之祝效华西南石油大学机电工程学院西南石油大学地热能研究中心

利用废弃油井开发地热资源是降低地热开发成本、促进商业推广的有效措施,其中层温衰减规律对地热系统取热效果具有重要影响。为此,以废弃油井储层为研究对象,结合泰森多边形理论对储层裂缝进行了划分,建立了三维油水两相热流耦合数值模... 详细信息

利用废弃油井开发地热资源是降低地热开发成本、促进商业推广的有效措施,其中层温衰减规律对地热系统取热效果具有重要影响。为此,以废弃油井储层为研究对象,结合泰森多边形理论对储层裂缝进行了划分,建立了三维油水两相热流耦合数值模型,分析了不同储层条件与布井结构下的层温衰减规律,探究了注入参数等因素对地热注采性能的影响。研究结果表明:(1)低渗透储层抽采30年生产温度最大差值可达22.08 K,高渗透储层(1.0×10^(-13) m^(2))温度过度衰减,长年限采热效率低;(2)储层含油率与生产温度和发电功率呈正相关关系,生产30年后差值最大可达11.57 K与0.12 MW;(3)分支井沿垂直方向会形成低温波谷,层温衰减高于储层其余部分,数量增加对注采影响小;(4)注入速率与发电功率、生产温度分别呈正、负相关关系,但注入速率超过89 kg/s时不利于长年限开采。结论认为:(1)储层取热性能对初始渗透率最为敏感,注入速率与储层含油率次之,优先开发低渗透储层有利于长年限采热;(2)应利用油田地热降低稠油黏度,形成地热辅助采油模式,以实现经济效应最大化;(3)选取6支分支井与89 kg/s的注入速率可得到可观取热效果和较好的经济效益。

关键词：地热系统废弃油井泰森多边形离散裂缝网络初始含油率层温衰减取热性能多分支井

熔体超温处理对GH742返回料凝固组织和力学性能的影响

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稀有金属材料与工程 2022年第11期51卷 4270-4278页

作者：王常帅吴云胜张丰之田强周兰章中国科学院金属研究所师昌绪先进材料创新中心辽宁沈阳110016 钢铁研究总院高温材料研究所北京100081

采用熔体超温处理方法考察了熔体超温处理温度对GH742返回料凝固组织和力学性能的影响规律。结果表明:当熔体超温处理温度低于1550℃时,随熔体超温处理温度的升高,晶粒和枝晶组织显著细化,枝晶偏析和合金中N、O、S元素含量降低,然而,温... 详细信息

采用熔体超温处理方法考察了熔体超温处理温度对GH742返回料凝固组织和力学性能的影响规律。结果表明:当熔体超温处理温度低于1550℃时,随熔体超温处理温度的升高,晶粒和枝晶组织显著细化,枝晶偏析和合金中N、O、S元素含量降低,然而,温度进一步升高至1600℃,晶粒和枝晶组织粗化、枝晶偏析增大、合金中N、O含量升高。熔体超温处理显著影响枝晶干γ′相特征,却对MC型碳化物影响较小。MC型碳化物形貌为棒状或块状,且随熔体超温处理温度升高无明显变化,但尺寸和面积分数均略微减小。枝晶干γ′相形态则随熔体超温处理升高由近球形向近立方状转变,尺寸呈现先增后减趋势。合适的熔体超温处理可显著提高返回料的室温抗拉伸强度,但对塑性无明显影响,其原因被归因于凝固组织的变化。

关键词：熔体超温处理凝固组织枝晶偏析力学性能 GH742

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基于生存分析的自动驾驶接管时间分析

中国安全科学学报 2023年第8期33卷 142-148页

作者：王长帅徐铖铖邵永成佟昊彭畅东南大学交通学院江苏南京210096

为探究有条件自动驾驶接管过程中非驾驶相关任务、接管请求时间、接管事件类型及交通流量对接管时间的影响,利用正交试验原理设计并搭建接管场景,招募驾驶人进行自动驾驶接管试验,采集试验过程中的车辆运行状态及驾驶人行为数据,分析不... 详细信息

为探究有条件自动驾驶接管过程中非驾驶相关任务、接管请求时间、接管事件类型及交通流量对接管时间的影响,利用正交试验原理设计并搭建接管场景,招募驾驶人进行自动驾驶接管试验,采集试验过程中的车辆运行状态及驾驶人行为数据,分析不同因素对驾驶人接管时间的影响,并构建随机效应生存分析模型,预测接管时间。结果表明:与无次任务相比,执行非驾驶相关任务会显著增加接管时间;接管请求时间为4 s时的接管时间要显著小于5和6 s时的接管时间;与施工区事件相比,事故车辆与换道并减速事件下驾驶人的接管时间较长;交通流量越大,接管时间越短。相比于固定效应生存分析模型,随机效应生存分析模型能揭示数据中未观测到的异质性,具有良好的拟合优度及预测效果。

关键词：自动驾驶接管时间驾驶模拟生存分析随机效应