Results 51 to 60 of about 244,861 (311)

Laser Spatial Coherence Suppression With Refractive Optical Elements Toward the Improvement of Speckle Reduction by Light Pipes

IEEE Access, 2019
We study laser speckle reduction by light pipes, and we propose a new method to improve its efficiency. Proof-of-concept refractive optical elements (ROEs) with a staircase-like structure are introduced before a holographic diffuser to split a laser beam
Zhaomin Tong, Changyuan Sun, Yifei Ma, Mei Wang, Suotang Jia, Xuyuan Chen   +5 more
doaj   +1 more source

Thermomechanical Fatigue and Creep–Fatigue Interaction of Inconel 718 Additively Manufactured by Laser Beam Powder Bed Fusion

Advanced Engineering Materials, EarlyView.
Thermomechanical fatigue tests of laser beam powder bed fusion (PBF‐LB) Inconel 718 show that the additively manufactured material reaches almost the lifetimes of conventionally‐rolled material under no‐dwell conditions. Introducing dwell times at the maximum temperature markedly reduces the lifetimes due to pronounced grain boundary sliding associated
Stefan Guth, Tomáš Babinský, Jan Lars Riedel, Wen Hao Kan, Aijun Huang, Martin Heilmaier, Ivo Šulák   +6 more
wiley   +1 more source

Off-Beam Acoustic Micro-Resonator for QEPAS Sensor with a Custom Quartz Tuning Fork

Atmosphere
Quartz-enhanced photoacoustic spectroscopy (QEPAS) has shown great promise for monitoring greenhouse gases and pollutants with a high measurement accuracy and limit of detection.
Yong Wang, Gang Wang, Jiapeng Wang, Chaofan Feng, Qingyuan Tian, Yifan Chen, Ruyue Cui, Hongpeng Wu, Lei Dong   +8 more
doaj   +1 more source

Beat frequency quartz-enhanced photoacoustic spectroscopy for fast and calibration-free continuous trace-gas monitoring

Nature Communications, 2017
Quartz-enhanced photoacoustic spectroscopy is a sensitive gas detection method whereby radiation-induced sound waves from gas absorption are detected. Here, Wuet al. use the beat frequency between a modulated laser and a tuning fork resonance to increase
Hongpeng Wu, Lei Dong, Huadan Zheng, Yajun Yu, Weiguang Ma, Lei Zhang, Wangbao Yin, Liantuan Xiao, Suotang Jia, Frank K. Tittel   +9 more
doaj   +1 more source

Creating Ti–Fe α/β Alloys by Diffusion‐Driven Solid‐State Processing

Advanced Engineering Materials, EarlyView.
This study proposes making alloys containing fast diffusing elements that are difficult to produce by ingot metallurgy, by diffusion‐driven solid‐state HIP processing of elemental powders and low‐temperature homogenisation. Here, novel Fe‐Ti α–β alloys are formed having fine α–β lamellae, a small β prior grain size without significant intermetallics ...
Jiaqi Xu, Xun Zhang, Jack M. Donoghue, Albert D. Smith, Rahul Unnikrishnan, Rhys Thomas, Vahid Nekouie, Jie Luo, Dongchen Hu, Michael Preuss, Philip J. Withers   +10 more
wiley   +1 more source

High‐Temperature Nanoindentation of Metals: Assessing Thermal Drift, Frame Compliance, and Chemical Composition Effects on the Reported Mechanical Properties

Advanced Engineering Materials, EarlyView.
Do not let thermal drift and instrument artifacts deceive high‐temperature nanoindentation results. We compare classical Oliver–Pharr and automatic image recognition analyses across steels and a Ni alloy to quantify these effects. Accounting for artifacts reveals systematic softening with temperature, while Cr and Ni additions boost resistance ...
Velislava Yonkova, Steffen Brinckmann, Ruth Schwaiger   +2 more
wiley   +1 more source

Efficient quantum random number generation via simultaneously detecting photons in temporal and spatial dimensions

Scientific Reports
Quantum random number generators (QRNGs) produce true random numbers with significant applications in quantum communication and numerical computation, where high-rate random number generation is critical.
Bingkun Wang, Jianyong Hu, Xingjian Li, Jianqiang Liu, Shuxiao Wu, Haizhen Li, Liwen Zhang, Changgang Yang, Zhixing Qiao, Ruiyun Chen, Guofeng Zhang, Chengbing Qin, Liantuan Xiao, Suotang Jia   +13 more
doaj   +1 more source

Fiber-Amplifier-Enhanced QEPAS Sensor for Simultaneous Trace Gas Detection of NH3 and H2S

Sensors, 2015
A selective and sensitive quartz enhanced photoacoustic spectroscopy (QEPAS) sensor, employing an erbium-doped fiber amplifier (EDFA), and a distributed feedback (DFB) laser operating at 1582 nm was demonstrated for simultaneous detection of ammonia (NH3)
Hongpeng Wu, Lei Dong, Xiaoli Liu, Huadan Zheng, Xukun Yin, Weiguang Ma, Lei Zhang, Wangbao Yin, Suotang Jia   +8 more
doaj   +1 more source

Current Status and Challenges in Data Collection for Aerospace Coatings Deposited by Plasma Spraying

Advanced Engineering Materials, EarlyView.
An innovative approach has been integrated into the GRENAT project to optimize plasma spraying and coating performance. Raw materials are accelerated and melted in the plasma generated by torches, creating coatings. Monitoring sensors collect process data which are combined with ex situ characterization data.
Lila Randriamananjara, Vincent Rat, Quentin Dubreuil, Patrice Valorge, Simon Goutier, Alain Denoirjean, Olivier Messe, Céline Ruelle, Jean‐Philippe Poli   +8 more
wiley   +1 more source

Detecting complex-energy braiding topology in a dissipative atomic simulator with transformer-based geometric tomography

Nature Communications
Machine learning (ML) is shaping our exploration of topological matter, whose existence is inherently tied to the geometry of quantum states or energy spectra.
Yang Yue, Nan Li, Xin Zhang, Chenhao Wang, Zeming Fang, Zhonghua Ji, Liantuan Xiao, Suotang Jia, Yanting Zhao, Liang Bai, Ying Hu   +10 more
doaj   +1 more source