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Optical Temperature Sensor Using Infrared-to-Visible-Frequency Upconversion in Er ^(3+)/Yb ^(3+)−Codoped Bi3TiNbO9 Ceramics

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Chinese Physics Letters 2011年第8期28卷 311-313页

作者： chen heng-zhi YANG Bin SUN Yan ZHANG Ming-Fu WANG Zhu ZHANG Rui ZHANG zhi-Guo CAO Wen-Wu Center for Condensed Matter Science and Technology Department of PhysicsHarbin Institute of TechnologyHarbin 150001 Center for Composite Materials Harbin Institute of TechnologyHarbin 150001 Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

An optical temperature sensor based on infrared-to-visible upconversion emission in Er ^(3+)/Yb ^(3+)co−doped Bi3TiNbØ9(BTN)ceramics is *** fluorescence intensity ratio of the green upconversion photoluminescence(UC−PL)around 524 nm and 545 nm depends on *** operating temperature range and the maximum sensitivity of Er ^(3+)/Yb ^(3+)co−doped Bi_(3)TiNbO_(9) ceramics are 123–693 K and 0.0032 K^(−1),***:Er3+/Yb3+ceramic has good thermal,physical and chemical stability,great UC−PL intensity and low cost *** results imply that Er ^(3+)/Yb ^(3+)co−doped Bi3TiNbO9 ceramic is promising for applications in wide-temperature-range sensors.

关键词： ceramics ceramic temperature

Ultrafast pulse-dilation framing camera and its application for time-resolved X-ray diagnostic

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Nuclear Science and Techniques 2024年第7期35卷 101-114页

作者： Hou-zhi Cai Qiu-Yan Luo Kai-Xuan Lin Xuan Deng Jun-Kai Liu Kai-zhi Yang Dong Wang Jia-Jie chen Jia-heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan Liu Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province Shenzhen Key Laboratory of Photonics and BiophotonicsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China

An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were *** camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic *** spatial resolution characteristics of the camera were studied both theoretically and *** results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the ***,the camera was used to detect the X-rays produced by the laser-targeting *** diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps.

关键词： Inertial confinement fusion Plasma diagnostics Framing camera Combined lenses Pulse-dilation

Revolution in thermoelectric cooling using PbSe thermoelectrics by grid plainification

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Science China Materials 2024年第5期67卷 1672-1673页

作者： Xiao-Lei Shi Qingfeng Liu zhi-Gang chen School of Chemistry and Physics ARC Research Hub in Zero-emission Power Generation for Carbon Neutralityand Centre for Materials ScienceQueensland University of TechnologyBrisbaneQueensland4000Australia State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Thermoelectric materials and devices enable direct conversion between heat and electricity,holding potential applications in thermoelectric power generation,localized cooling,and electronic thermal management[1].Howev... 详细信息

关键词： enable thermoelectric constrained

Wettability regulation from superhydrophilic to superhydrophobic via nanosecond laser ablation

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Science China(Technological Sciences) 2024年第6期67卷 1829-1841页

作者： chen zhi WU zhicheng ZHANG GuoJun LI DongHui HAN FengLin State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha410083China Guangdong Provincial Key Laboratory of Manufacturing Equipment Digitization Guangdong HUST Industrial Technology Research InstituteDongguan523808China China Harzone Industry Corp. Ltd.Wuhan430299China

Metal surfaces play a crucial role in numerous applications,from self-cleaning and anti-icing to anti-fogging and oil-water *** regulation of their wettability is essential to enhance their performance in these *** paper proposes a multi-state regulation method for metal surface wettability,leveraging nanosecond laser *** creating non-uniform microstructures on a metal surface,the contact area between the solid and liquid phases can be increased,resulting in the attainment of superhydrophilic properties(contact angle(CA),ranging from 4.6°to 8.5°).Conversely,the construction of uniform microstructures leads to a decreased solid-liquid contact area,thereby rendering the metal surface hydrophilic(CA=12.2°–53°).Furthermore,through heat treatment on a surface with uniform microstructures,organic matter adsorption can be promoted while simultaneously reducing surface *** process results in the metal surface acquiring hydrophobic properties(CA=92.1°–133.5°),facilitated by the“air cushion effect.”Building on the hydrophobic surface,stearic acid modification can further reduce surface energy,ultimately bestowing the metal surface with superhydrophobic properties(CA=150.1°–152.7°,and sliding angle=3.8°).Performance testing has validated the durability and self-cleaning effectiveness of the fabricated superhydrophobic surface while also highlighting the excellent anti-fog performance of the superhydrophilic *** findings strongly indicate the immense potential of these surfaces in various engineering applications.

关键词： nanosecond laser ablation surface wettability superhydrophobic superhydrophilic

Lewis Base Catalyzed Selenofunctionalization of Alkynes with Acid-Controlled Divergent Chemoselectivity

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Chinese Journal of Chemistry 2024年第14期42卷 1623-1629页

作者： Ling-Ling chen Ren-Fei Cao Hua Ke zhi-Min chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai200240 China Engineering Technology Research Center for Environmental Protection Materials Pingxiang UniversityPingxiangJiangxi337055 China

Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first *** selenium-containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z *** the substrates were 1-ethynyl naphthol derivatives,linear selenium-containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive;in contrast,cyclic selenium-containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid.

关键词： Alkynes Electrophilic addition Chemoselectivity Lewis base catalysis Selenofunctionalization

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杭州湾大桥梁上运梁过程仿真分析

中国铁道科学 2005年第5期26卷 22-25页

作者：徐爱敏陈衡治张治成浙江大学建工学院

对杭州湾大桥非通航孔滩涂区的50 m箱梁上运梁过程进行空间仿真分析。按照实际工况荷载,考虑预应力空间效应,施加等效节点力,并合理考虑支座等细部建模,建立精密的三维实体有限元仿真模型。混凝土的材料特性按现行公路桥梁设计规范取值... 详细信息

对杭州湾大桥非通航孔滩涂区的50 m箱梁上运梁过程进行空间仿真分析。按照实际工况荷载,考虑预应力空间效应,施加等效节点力,并合理考虑支座等细部建模,建立精密的三维实体有限元仿真模型。混凝土的材料特性按现行公路桥梁设计规范取值,考虑最不利计算荷载,支座底部按刚性单元模拟,而与梁相接触层的弹性模量满足梁端回转变形时不出现拉应力,在结构离散时尽可能细分单元网格,由于梁端的应力相对复杂,采用比跨中更密的单元网格。计算承重箱梁整体变形和空间应力分布特性,结果为,由于载荷位置在支座附近,变形相对较小,最大挠度在反拱位移之内。支座截面的最大主拉应力发生在底板上表面侧,超过混凝土的开裂强度,因此,对该区域的混凝土应采取加劲处理,以防止混凝土拉裂;最大主压应力发生在架桥机肢腿处附近,小于混凝土的抗压强度。

关键词：杭州湾大桥梁上运梁有限元仿真空间应力分布局部应力

Magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

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Nano Research 2024年第7期17卷 6630-6637页

作者： Ke Liu zhi Qin Jie Shen zhi cheng Shiyue You Liang Ma Jing Zhou Wen chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis

Preparation of PVA/GO/h-BN Janus Film with High Thermal Conductivity and Excellent Flexibility via a Density Deposition Self-assembly Method

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Chinese Journal of Polymer Science 2024年第8期42卷 1217-1226页

作者： Fang-Hua Luo zhi-Tao Dong Guo-Hua chen chen Ma Huai-Yuan Wang College of Chemistry and Chemical Engineering Northeast Petroleum UniversityDaqing 163318China College of Materials Science and Engineering Huaqiao UniversityXiamen 361000China School of Chemical Engineering and Technology and State Key Laboratory for Chemical Engineering Tianjin UniversityTianjin 300350China

Janus films with asymmetric physical/chemical properties have attracted con siderable attention due to their promising applications in personal thermal management,electronic skin s,sensors,actuators,***,traditional methods for fabricating Janus films conventionally need the assistance of an interface or auxiliary equipment,which are usually complex and ***,flexible poly(vinyl alcohol)(PVA)/graphene oxide(GO)/h-BN(recorded as PVA/GO/h-BN)Janus films with thermally,optically,and electrically anisotropic properties are fabricated by a simple density deposition self-assem bly method,which just utilizes the density difference between GO and h-BN during water *** results show that the two sides of the acquired Janus films have obvious asymmetric *** the original state of the PVA/GO/h-BN Janus films,the thermal conductivity of the GO side(10.06 W·m^(-1)·K^(-1))is generally lower than that of the h-BN side(10.48W·m^(-1)·K^(-1)).But after GO is reduced,the thermal conductivity of the rGO side reaches 12.17 W·m^(-1)·K^(-1),surpassing that of the h-BN *** addition,the relative reflectance of the h-BN side of Janus film is also significantly higher than that of the rGO side,and the su rface resistance difference between the two sides is about 4 orders of *** prepared PVA/GO/h-BN Janus films show great application potential in human thermal management,light conversion switches,and electronic *** study provides a simple and versatile strategy for fabricating Janus films with multifunctional(such as thermal,optical,and electrical)anisotropies.

关键词： Janus films PVA/GO/h-BN Density deposition self-assembly method

Neutron irradiation influence on high-power thyristor device under fusion environment

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Nuclear Science and Techniques 2024年第4期35卷 65-81页

作者： Wei Tong Hua Li Meng Xu zhi-Quan Song Bo chen School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

Because of their economy and applicability,high-power thyristor devices are widely used in the power supply systems for large fusion *** high-dose neutrons produced by deuterium–tritium(D–T)fusion reactions are irradiated on a thyristor device for a long time,the electrical characteristics of the device change,which may eventually cause irreversible *** this study,with the thyristor switch of the commutation circuit in the quench protection system(QPS)of a fusion device as the study object,the relationship between the internal physical structure and external electrical parameters of the irradiated thyristor is ***,a series of targeted thyristor physical simulations and neutron irradiation experiments are conducted to verify the accuracy of the theoretical *** addition,the effect of irradiated thyristor electrical characteristic changes on the entire QPS is studied by accurate simulation,providing valuable guidelines for the maintenance and renovation of the QPS.

关键词： Fusion device Neutron irradiation effects Thyristor Quench protection