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Rare Metals 2024年第5期43卷 2275-2281页

作者： Guo-Chao Li Xu Cheng Hua-Ming Wang National Engineering Laboratory of Additive Manufacturing for Large Metallic components and Engineering Research Center of Ministry of Education on laser Direct Manufacturing for Large Metallic components School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar *** this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si was *** results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' *** at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine *** increasing the aging temperature,the number of α_(s) decreases but with coarsened *** aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°*** changing size of α_(s) obviously influences the property of the *** fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties.

关键词： α+βtitanium alloy laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property

Additive manufacturing of NiTi lightweight porous structures bio-mimicking coral skeleton with enhanced mechanical properties and shape memory functions

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Science China(Technological Sciences) 2024年第8期67卷 2461-2474页

作者： LIU Xin GU DongDong YUAN LuHao ZHANG Han SUN JianFeng CHEN WenXin WANG Jie SHI KeYu Jiangsu Provincial Research Center for laser Additive Manufacturing of High-Performance components College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

Concerning the high demand for lightweight and multifunctional properties of engineering structures, the coral skeleton-inspired sheet-based(CSS) structure, which was a novel bio-mimicking coral skeleton wall-septa architecture with a unique ability to resist wave shocks was fabricated using NiTi alloy by laser powder bed fusion(LPBF) technology. The effects of laser energy density(LED) on surface morphologies, microstructures, phase transformation behavior, and mechanical properties of LPBFfabricated CSS structures were systematically investigated. The results indicated that the size deviation was predominantly governed by powder adhesion and step effect. NiTi CSS structures with LED of 71 J·mm~(-3)possessed superior compressive modulus(~400 MPa), ultimate strength(~13 MPa), and energy absorption efficiency(~69%). The compression fracture mechanism of the LPBF-fabricated NiTi CSS structures was revealed to be predominantly brittle fracture accompanied by ductile fracture. Furthermore, the Ni_4Ti_3 nanoprecipitates induced the precipitation strengthening effect, enabling better shape memory response at LED of 71 J·mm~(-3), with a recoverable strain of 3.63% and recovery ratio of 90.8%, after heating under a pre-strain of 4%. This study highlights the importance of a bionic design strategy for enhancing the mechanical properties of NiTi components and offers the possibility to tailor its functional properties.

关键词： bioinspired structures laser powder bed fusion NiTi shape memory alloy mechanical performance

A high aspect ratio surface micromachined accelerometer based on a SiC-CNT composite material

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Microsystems & Nanoengineering 2024年第2期10卷 219-230页

作者： Jiarui Mo Shreyas Shankar Roberto Pezone Guoqi Zhang Sten Vollebregt Laboratory of Electronic components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands

Silicon carbide(SiC)is recognized as an excellent material for microelectromechanical systems(MEMS),especially those operating in challenging environments,such as high temperature,high radiation,and corrosive ***,SiC bulk micromachining is still a challenge,which hinders the development of complex SiC *** address this problem,we present the use of a carbon nanotube(CNT)array coated with amorphous SiC(a-SiC)as an alternative composite material to enable high aspect ratio(HAR)surface *** using a prepatterned catalyst layer,a HAR CNT array can be grown as a structural template and then densified by uniformly filling the CNT bundle with LPCVD *** electrical properties of the resulting SiC-CNT composite were characterized,and the results indicated that the electrical resistivity was dominated by the *** demonstrate the use of this composite in MEMS applications,a capacitive accelerometer was designed,fabricated,and *** fabrication results showed that the composite is fully compatible with the manufacturing of surface micromachining *** Young’s modulus of the composite was extracted from the measured spring constant,and the results show a great improvement in the mechanical properties of the CNTs after coating with *** accelerometer was electrically characterized,and its functionality was confirmed using a mechanical shaker.

关键词： composite surface electrical

Influence of Nd^(3+) concentration on mid-infrared emission in PbF_(2) crystal co-doped with Ho^(3+) and Nd^(3+) ions

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Journal of Rare Earths 2024年第3期42卷 479-487,I0002页

作者： Yan Chen Juncheng Tan Peixiong Zhang Weibi Zheng Lin Li Lianhan Zhang Zhen Li Yin Hang Zhenqiang Chen department of Optoelectronic Engineering Jinan UniversityGuangzhou510632China Guangdong Provincial Engineering Research Centerof Crystal and laser Technology.Guangzhou 510632China Research Center of laser Crystal Key Laboratory of High Power Laser MaterialsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai201800China

A promising series of Ho_(y)Nd_(x)Pb_((1-x-y))F_2(x = 0, 0.01, 0.02, 0.03, 0.04;y = 0.02) crystals was grown by the Bridgman method. The influence of the Nd^(3+)ions concentration on mid-infrared(~2.0, ~2.9 and ~3.9 μm)fluorescence emissions of Ho^(3+)ions in the PbF_(2) crystal excited by 808 nm laser diode was investigated in this work. The energy transfer mechanism between Nd^(3+)ions and Ho~(3+)ions under different concentrations of the Nd^(3+)ions was systematically analyzed. The results show that the Nd^(3+)ions have good sensitization and deactivation effect on the Ho^(3+)ions to stimulate the mid-infrared fluorescence emissions. The experimental analysis proves that the sensitization efficiency of the Nd^(3+)ions is relatively stable at around 93.45% with varying Nd^(3+)-doping concentrations. Concentration dependence studies indicate that the concentration of the Nd^(3+)ions has significant influence on mid-infrared *** the doping concentration of the Nd^(3+)ions is up to 2.0 at%, the intensity of ~2.0, ~2.9 and ~3.9 μm emissions all reach the maximum. The output characteristics of a 3.9 μm laser are simulated, and it is found that with the increase of the Nd^(3+)-doping concentration, the peak power, pulse width, and peak energy all meet the trend of first increasing and then decreasing, and Ho_(0.02)Nd_(0.02)Pb_(0.96)F_(2) crystal displays the best performance. All the results show that the Nd^(3+)/Ho^(3+)co-doped PbF_(2) crystals might act as a useful optical medium for mid-infrared laser applications.

关键词： Crystal growth Mid-infrared PbF_(2) Rare earth ions

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.Huang K.Jiang C.N.Wu H.Peng P.C.hen R.Li H.B.Zhuo C.T.Zhou Shenzhen Key Laboratory of Ultraintense laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Dynamic 3D holographic projection of vectorial images with a multimode fiber

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Photonics Research 2024年第6期12卷 1344-1350页

作者： JINGHAN ZHUANG PANPAN YU YIFAN LIU YIJING WU ZIQIANG WANG YINMEI LI LEI GONG department of Optics and Optical Engineering University of Science and Technology of ChinaHefei 230026China Advanced laser Technology Laboratory of Anhui Province Hefei 230026China

An optical multimode fiber(MMF)is capable of delivering structured light modes or complex images with high ***,we present a holographic approach to enable the MMF as a 3D holographic projector with the capability of complete polarization *** harnessing the strong coupling of the spatial and polarization degrees of freedom of light propagating through MMFs,our approach realizes active control of the output intensity and polarization in 3D space by shaping only the wavefront of the incident *** this manner,we demonstrate MMF-based holographic projection of vectorial images on multiple planes via a phase-only ***,dynamic projection of polarization-multiplexed grayscale images is presented with an averaged Pearson correlation coefficient of up to *** work is expected to benefit fiber-based holographic displays,data transmission,optical imaging,and manipulation.

关键词： holographic projection enable

The modeling non-sequential double ionization of helium atom under highintensity femtosecond laser pulses with shielding charge approximation

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Communications in Theoretical Physics 2024年第2期76卷 151-156页

作者： Marjan Zakavi Mohammad Sabaeian department of Physics Faculty of ScienceShahid Chamran University of AhvazIran Center for Research on laser and Plasma Shahid Chamran University of AhvazIran

In this study,we successfully extracted the‘knee structure’for non-sequential double ionization(NSDI)in the helium *** achieve this,for the first time,we solved the time-dependent Schrödinger equation in three dimensions for the helium atom,utilizing the shielding charge *** findings corroborate prior observations by Wang et al[Wang and Eberly,***.105,083001(2010)],demonstrating that NSDI occurs within a narrower time window in circular polarization compared to linear *** a result,the yield of linear polarization was higher than that of circular polarization,aligning with the previously reported ***,in the case of circular polarization,the time window further narrows with increasing intensity,attributed to a decrease in the time-of-flight.

关键词： NSDI knee structure TDSE shielding charge helium 3D-TDSE

Structural,optical and dielectric investigations on RECr_(0.85)Mn_(0.15)O_(3)(RE=Ho,Gd and Pr) nanoparticles

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Journal of Rare Earths 2024年第2期42卷 399-408,I0006页

作者： Komal Kanwar Sonali Pradhan S.Satapathy Yugandhar Bitla Neeraj Panwar department of Physics Central University of Rajasthan BandarsindrAjmer305817RajasthanIndia laser Material Section HBNIRaja Ramanna Centre for Advanced TechnologyIndore452013India

We hereby report the room-temperature structural and optical characterization of RECr_(0.85)Mn_(0.15)O_(3)(RECMO,RE=Ho,Gd and Pr) compounds synthesized by the auto-combustion sol-gel *** low temperature dielectric properties are also *** RECMO compounds crystallize in an orthorhombic Pbnm symmetry with an average grain size range of 51-80 *** analysis reveals an increase in the structural distortion compared to that of the undoped bulk *** measurements exhibit a significant reduction in bandgap values for RECMO nanoparticles when compared with their undoped bulk ***,from the absorbance measurements various optical parameters such as skin depth,extinction coefficient,refractive index and optical conductivity were also *** dielectric analysis confirms the lower values of the dielectric permittivity and dielectric loss than those of their corresponding bulk *** conductivity versus frequency and temperature data are fitted according to the Jonscher's power law and Arrhenius law,*** small polaron hopping is responsible for the electric conduction in these *** tunability of the optical and dielectric properties as a result of substitution and particle size reduction makes these materials useful for various potential applications in photocatalysis,optoelectronics and low permittivity dielectrics.

关键词： Rare-earth orthochromites Nanoparticles Optical properties Dispersion parameters Dielectric properties Small polaron hopping

Simultaneously detecting transversal and longitudinal displacement with the dielectric metasurface

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Chinese Optics Letters 2024年第2期22卷 109-113页

作者：张植宇匡程辉臧昊峰鲁拥华王沛 department of Optics and Optical Engineering University of Science and Technology of ChinaHefei 230026China Advanced laser Technology Laboratory of Anhui Province Hefei 230026China

The compact,sensitive,and multidimensional displacement measurement device plays a crucial role in semiconductor manufacture and high-resolution optical *** metasurface offers a promising solution to develop high-precision displacement *** this work,we proposed and experimentally demonstrated a two-dimensional displacement(XZ)measurement device by a dielectric *** transversal and longitudinal displacements of the metasurface can be obtained by the analysis of the interference optical intensity that is generated by the deflected light beams while the metasurface is under linearly polarized *** experimentally demonstrated that displacements down to 5.4 nm along the x-axis and 0.12μm along the z-axis can be resolved with a 900μm×900μm *** work opens up new possibilities to develop a compact high-precision multidimensional displacement sensor.

关键词： metasurface transversal and longitudinal displacement measurement

Instantaneous preparation of gold-carbon dot nanocomposites for on-site SERS identification of pathogens in diverse interfaces

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Photonics Research 2024年第6期12卷 1303-1312页

作者： YANXIAN GUO YE LIU CHAOCAI LUO YUE ZHANG YANG LI FEI ZHOU ZHOUYI GUO ZHENGFEI ZHUANG ZHIMING LIU School of Electronic Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China department of Physics University of Science and Technology of ChinaHefei 230026China MOE Key Laboratory of laser Life Science&Guangdong Provincial Key Laboratory of laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou 510631China

Rapid detection of pathogens present on contaminated surfaces is crucial for food safety and public health due to the high morbidity and mortality of bacterial ***,a sensitive and efficient method for on-site identification of foodborne pathogens on anisotropic surfaces was developed by using an in situ instantaneously prepared surface-enhanced Raman scattering(SERS)*** achieve this,molybdenum-doped gallic acidderived carbon dots(MCDs)are utilized as the reductant for synthesizing Au@MCDs nanohybrids within just 3 s at ambient *** synergistic effect of the electromagnetic enhancement and charge transfer of Au@MCDs enables excellent SERS performance 10 times stronger than bare Au *** bioassay platform requires less than 5 min to complete the quantitative detection of foodborne pathogens on various microbial-contaminated interfaces with a sensitivity of 10 CFU/m *** innovative strategy breaks the long-standing limitations of SERS substrates in practical use,such as the time-consuming process,interference of residual surfactants,poor surface stability,and few application scenarios,providing a promising tool for widespread applications in biomedical research and clinical diagnostics.

关键词： temperature molybdenum consuming