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Oxidation induced crack healing of CR2(AL,SI)C MAX phase ceramic

Shen, L. (author), Li, S.B. (author), Van der Zwaag, S. (author), Sloof, W.G. (author)

The oxidation crack healing of Cr2AlC and Cr2(Al,Si)C was studied and compared with known healing of Ti2AlC. The oxidation induced crack healing of Ti2AlC is relatively fast and leads to full strength recovery, but the oxidation product contains besides ?-Al2O3 also undesired TiO2. However, when oxidizing Cr2AlC only ?-Al2O3 is formed, but full...

conference paper 2013

document

Oxidation induced crack healing of Cr2(Al,Si)C max phase ceramic

Shen, L. (author), Li, S.B. (author), Van der Zwaag, S. (author), Sloof, W.G. (author)

The oxidation crack healing of Cr2AlC and Cr2(Al,Si)C was studied and compared with known healing of Ti2AlC. The oxidation induced crack healing of Ti2AlC is relatively fast and leads to full strength recovery, but the oxidation product contains besides ?-Al2O3 also undesired TiO2. However, when oxidizing Cr2AlC only ?-Al2O3 is formed, but full...

conference paper 2013

document

Effects of wheelset flexibility on the simulation of vehicle-track interaction at crossings

Shen, C. (author), Wei, Z. (author), Burgelman, N.D.M. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

Though numerical models based on multi-body dynamics (MBD) are often used to simulate the vehicle-track interaction at crossing impact, their relative capabilities and accuracy were not discussed. This paper aims to investigate the influence of wheelset flexibility on the result of crossing impact simulation in the frequency range 0–500 Hz. Two...

conference paper 2016

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Comparison of vehicle-track interaction models to simulate vertical wheel/rail impact contact

Shen, C. (author), Sabbatini, L. (author), Wei, Z. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

This study compares various assumptions in different models to assess their capabilities to model vehicle-track interactions up to 2 kHz at a single rail-top defect. Field measurement data are used to evaluate discrepancies. The characteristics of contact force and axle-box acceleration (ABA) are first identified and qualitatively correlated...

conference paper 2018

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A Novel Method for Railway Crossing Monitoring Based on Ambient Vibration Caused by Train-Track Interaction

Shen, C. (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)

Railway crossings are critical components in the rail network. They usually degrade faster than the other components. It is therefore vital to monitor their conditions using appropriate methods. This paper proposes to use the ambient vibration caused by the train-track interaction from a distance to monitor the condition of railway crossings....

conference paper 2020

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A Buried Vertical Filter for Micro and Nanoparticle Filtration

Li, S.J. (author), Shen, C. (author), Sarro, P.M. (author)

This paper presents a silicon micromachined filter for micro- and nanoparticles. The filter is vertical and completely buried beneath the surface. The buried aspect allows additional features to be integrated above the filter, while the vertical aspect allows the creation of highly uniform pores and efficient use of die area. The filter is...

journal article 2011

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A Wireless Near-Infrared Spectroscopy Device for Flap Monitoring: Proof of Concept in a Porcine Musculocutaneous Flap Model

Wu, Changsheng (author), Rwei, A.Y. (author), Lee, Jong Yoon (author), Ouyang, Wei (author), Jacobson, Lauren (author), Shen, Haixu (author), Luan, Haiwen (author), Xu, Yameng (author), Li, S. (author)

Background Current near-infrared spectroscopy (NIRS)-based systems for continuous flap monitoring are highly sensitive for detecting malperfusion. However, the clinical utility and user experience are limited by the wired connection between the sensor and bedside console. This wire leads to instability of the flap-sensor interface and may...

journal article 2021

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From Deterministic to Generative: Multimodal Stochastic RNNs for Video Captioning

Song, Jingkuan (author), Guo, Yuyu (author), Gao, Lianli (author), Li, Xuelong (author), Hanjalic, A. (author), Shen, Heng Tao (author)

Video captioning, in essential, is a complex natural process, which is affected by various uncertainties stemming from video content, subjective judgment, and so on. In this paper, we build on the recent progress in using encoder-decoder framework for video captioning and address what we find to be a critical deficiency of the existing...

journal article 2018

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Evaluating railway track stiffness using axle box accelerations: A digital twin approach

Shen, C. (author), Zhang, P. (author), Dollevoet, R.P.B.J. (author), Zoeteman, A. (author), Li, Z. (author)

While various train-borne techniques have been developed for measuring railway track stiffness, differentiating stiffness at different track layers remains a challenge. This study proposes a digital twin framework for the vehicle–track interaction system, which enables track stiffness evaluations based on axle box accelerations (ABA). The...

journal article 2023

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Comparisons between beam and continuum models for modelling wheel-rail impact at a singular rail surface defect

Shen, C. (author), Deng, X. (author), Wei, Z. (author), Dollevoet, R.P.B.J. (author), Zoeteman, A. (author), Li, Z. (author)

A singular rail or wheel surface irregularity, such as a squat, insulation joint or wheel flat, can cause large wheelrail impact force. Both the magnitude and frequency content of the impact force need to be correctly modelledbecause they are closely related to the formation, deterioration and detection of such irregularities. In this paper,we...

journal article 2021

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Fast and robust identification of railway track stiffness from simple field measurement

Shen, C. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

We propose to combine a physics-based finite element (FE) track model and a data-driven Gaussian process regression (GPR) model to directly infer railpad and ballast stiffness from measured frequency response functions (FRF) by field hammer tests. Conventionally, only the rail resonance and full track resonance are used as the FRF features to...

journal article 2021

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Probing magnetic correlations with spin-echo modulated small angle neutron scattering (SEMSANS)

Li, Fankang (author), Steinke, Nina J. (author), Dalgliesh, Robert M. (author), Washington, Adam L. (author), Shen, Jiazhou (author), Pynn, Roger (author), Parnell, S.R. (author)

The first measurements of magnetic correlation functions are presented using time-of-flight Spin-echo modulated small angle neutron scattering (SEMSANS) on the Larmor instrument at the ISIS pulsed neutron source. The accessible length scale is beyond that of the conventional SANS. A simplified model is presented to calculate the expected...

journal article 2021

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Neutron-state entanglement with overlapping paths

Kuhn, S. J. (author), McKay, S. (author), Shen, J. (author), Geerits, N. (author), Dalgliesh, R. M. (author), Dees, E. (author), Irfan, A. (author), Li, F. (author), Parnell, S.R. (author)

The development of direct probes of entanglement is integral to the rapidly expanding field of complex quantum materials. Here we test the robustness of entangled neutrons as a quantum probe by measuring the Clauser-Horne-Shimony-Holt contextuality witness while varying the beam properties. Specifically, we show that the mode entanglement of...

journal article 2021

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Comprehensive validation of three-dimensional finite element modelling of wheel-rail high-frequency interaction via the V-Track test rig

Zhang, P. (author), He, C. (author), Shen, C. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

Wheel-rail high-frequency interaction is closely related to the formation of railway short-wave defects. Finite element (FE) method has been widely used to simulate wheel-rail dynamic systems, but its validity in modelling high-frequency interaction has not been fully demonstrated in three dimensions (3D). This work aims at comprehensively...

journal article 2024

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Peroxygenase-Catalysed Sulfoxidations in Non-Aqueous Media

Li, Huanhuan (author), Shen, Qianqian (author), Zhou, Xiaoying (author), Duan, Peigao (author), Hollmann, F. (author), Huang, Yawen (author), Zhang, Wuyuan (author)

Chiral sulfoxides are valuable building blocks in asymmetric synthesis. However, the biocatalytic synthesis of chiral sulfoxides is still challenged by low product titres. Herein, we report the use of peroxygenase as a catalyst for asymmetric sulfoxidation under non-aqueous conditions. Upon covalent immobilisation, the peroxygenase showed...

journal article 2023

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Low-temperature drying of waste activated sludge enhanced by agricultural biomass towards self-supporting incineration

Li, Ji (author), Hao, Xiaodi (author), Shen, Zhan (author), Wu, Yuanyuan (author), van Loosdrecht, Mark C.M. (author)

A high moisture content of waste activated sludge (WAS) associated with a low calorific value needs to be deeply dried towards self-supporting incineration. On the other hand, thermal energy with low temperature exchanged from treated effluent has great potential for drying sludge. Unfortunately, low-temperature drying of sludge seems to be...

journal article 2023

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Vertical dynamic measurements of a railway transition zone: a case study in Sweden

Unsiwilai, S. (author), Shen, C. (author), Zeng, Y. (author), Wang, L. (author), Nunez, Alfredo (author), Li, Z. (author)

This study presents a measuring framework for railway transition zones using a case study on the Swedish line between Boden and Murjek. The final goal is to better understand the vertical dynamics of transition zones using hammer tests, falling weight measurements, and axle box acceleration (ABA) measurements. Frequency response functions ...

journal article 2024

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Degradation behaviors and in-vivo biocompatibility of a rare earth- and aluminum-free magnesium-based stent

Bian, Dong (author), Zhou, Xiaochen (author), Liu, Jianing (author), Li, Wenting (author), Shen, Danni (author), Zheng, Yufeng (author), Gu, Wenda (author), Jiang, Jingjun (author), Li, Mei (author), Chu, Xiao (author), Ma, Limin (author), Wang, Xiaolan (author), Zhang, Yu (author), Leeflang, M.A. (author), Zhou, J. (author)

Biodegradable stents can provide scaffolding and anti-restenosis benefits in the short term and then gradually disappear over time to free the vessel, among which the Mg-based biodegradable metal stents have been prosperously developed. In the present study, a Mg-8.5Li (wt.%) alloy (RE- and Al-free) with high ductility (> 40%) was...

journal article 2021

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Fabrication of graphene oxide-modified self-healing microcapsules for Cardanol-based epoxy anti-corrosion coatings

Wu, Wentao (author), Chu, Liangyong (author), Garcia, Santiago J. (author), van der Zwaag, S. (author), Li, Ming (author), Shen, Liming (author), Bao, Ningzhong (author)

In this paper, graphene oxide (GO) modified microcapsules have been developed for use in self-healing Cardanol-based epoxy anti-corrosion coatings on steel substrates. The microcapsules had a polymethyl methacrylate (PMMA) shell, covered with aminated GO flakes and contained either of the two complementary healing agents mixed with nanosized...

journal article 2023

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Laser shape variation influence on melt pool dynamics and solidification microstructure in laser powder bed fusion

Li, Erlei (author), Shen, Haopeng (author), Wang, L. (author), Wang, Geoff (author), Zhou, Zongyan (author)

The shape variation of the laser beam is evidently observed in the laser powder bed fusion (LPBF) process because of changes in laser incidence angle and misalignment between the build plate and the laser focus plane. This issue is particularly relevant in large-scale LPBF systems where the laser beam needs to scan a large build area. However...

journal article 2023