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Enhanced ferroelectricity and magnetism of quenched(1−x)BiFeO3-xBaTiO3 ceramics

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Journal of Advanced Ceramics 2020年第4期9卷 511-516页

作者： han Bai jun Li Yang Hong Zhongxiang Zhou School of Physics Harbin Institute of TechnologyHarbin150001China

Bismuth ferrite(BiFeO3)-based materials are multiferroic materials widely *** study reports that strong ferroelectricity and enhanced magnetic performance are simultaneously obtained in the quenched(1−x)BiFeO3−xBaTiO3(BFBT100x,x=0.2 and 0.3)*** treatment can reduce the amount of defects and Fe2+ions and make the defect dipole in a random state,which is conducive to improving the ferroelectricity and *** with the conventional sintered samples,the quenched ceramics have higher remnant and saturation *** for magnetism,the coercive field(Hc)of the quenched ceramics is smaller and the quenching treatment can increase the maximum magnetization by up to 15%.

关键词： multiferroics bismuth ferrite(BiFeO3)-based ceramics quenching treatment

Forecasting US Stock Market Returns:A Japanese Candlestick Approach

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Journal of Systems Science & Complexity 2021年第2期34卷 657-672页

作者： MENG Xiaoge MA jun QIAO han XIE Haibin School of Economics and Management Institute of Disaster PreventionSanhe 065201China Business School University of International Business and EconomicsBeijing 100029China School of Economics and Management University of Chinese Academy SciencesBeijing 100190China School of Banking and Finance University of International Business and EconomicsBeijing 100029China

A Japanese candlestick chart consists of not only the closing price but also the high,low and opening price *** the Japanese candlestick,this paper investigates the forecasting power of the shadow in Japanese candlestick *** studies performed with the US stock market show that 1)there is a significant Halloween effect in the shadow;2)shadow is valuable for predicting the stock market returns in both statistical and economic sense;3)the predictability reported by the shadow can not be explained by either the CAPM model or the Fama-French three-factor *** paper confirms that predictability of the stock market can be improved if more price information is used.

关键词： Japanese candlestick out-of-sample predictability US stock market

Artifacts Reduction Using Multi-Scale Feature Attention Network in Compressed Medical Images

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Computers, Materials & Continua 2022年第2期70卷 3267-3279页

作者： Seonjae kim Dongsan jun Department of Convergence IT Engineering Kyungnam UniversityChangwon51767Korea

Medical image compression is one of the essential technologies to facilitate real-time medical data transmission in remote healthcare *** general,image compression can introduce undesired coding artifacts,such as blocking artifacts and ringing *** this paper,we proposed a Multi-Scale Feature Attention Network(MSFAN)with two essential parts,which are multi-scale feature extraction layers and feature attention layers to efficiently remove coding artifacts of compressed medical *** feature extraction layers have four Feature Extraction(FE)*** FE block consists of five convolution layers and one CA block for weighted skip *** order to optimize the proposed network architectures,a variety of verification tests were conducted using validation *** used Computer Vision Center-Clinic Database(CVC-ClinicDB)consisting of 612 colonoscopy medical images to evaluate the enhancement of image *** proposedMSFAN can achieve improved PSNR gains as high as 0.25 and 0.24 dB on average compared to DnCNNand DCSC,respectively.

关键词： Medical image processing convolutional neural network deep learning telemedicine artifact reduction image restoration

Finite symmetry transformation group of the Konopelchenko Dubrovsky equation from its Lax pair

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Chinese Physics B 2012年第2期21卷 46-50页

作者： Hu han-Wei Yu jun Department of Physics Shaoxing UniversityShaoxing 312000China Department of Physics Ningbo UniversityNingbo 315211China

Starting from a weak Lax pair, the general Lie point symmetry group of the Konopelchenko-Dubrovsky equation is obtained by using the general direct method. And the corresponding Lie algebra structure is proved to be a Kac-Mood-Virasoro type. Furthermore, a new multi-soliton solution for the Konopelchenko-Dubrovsky equation is also given from this symmetry group and a known solution.

关键词： Lax pairs symmetries symmetry group exact solution

Gradient nanostructure,enhanced surface integrity and fatigue resistance of Ti-6Al-7Nb alloy processed by surface mechanical attrition treatment

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Journal of Materials Science & Technology 2024年第21期188卷 252-269页

作者： Hongwei Yang Zichun Zhang jun Shu Yong han State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Department of Orthopaedics The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China

Current Ti-based orthopedic implants often suffer from fatigue damage,therefore shortening their service *** solve this issue,in this study,mechanically polished Ti-6Al-7Nb(P-Ti6Al7Nb)was subjected to surface mechanical attrition treatment(SMAT).Effects of various SMAT process parameters,including ball diameter and treatment duration,on the surface integrity of P-Ti6Al7Nb were investigated,specifically in terms of surface quality,surface nanocrystalline layer,and residual ***,the microstructure,in-depth residual stress and microhardness distributions,surface roughness,and fatigue behavior in simulated body fluids of optimally SMATed Ti-6Al-7Nb(S-Ti6Al7Nb)were examined and compared to those of *** showed that based on the experimental conditions established in the present research,the optimal parameters were determined to be a 3 mm ball diameter and a 15 min treatment duration,which resulted in excellent surface integrity;S-Ti6Al7Nb showed a 300μm-thick gradient nanostructured layer comprising the thickest nanocrystalline layer of about 20μm,a 1000μm-deep residual compressive stress field with the maximum surface residual compressive stress,and a microconcave topography but free of any defects or *** microstructural evolution mechanism was also elucidated,revealing that the combination of multidirectional primary and secondary twins’intersections and twin-dislocation interactions contributed to grain *** to P-Ti6Al7Nb,S-Ti6Al7Nb exhibited a 40%improvement in fatigue strength,owing to synergistic effects of the gradient nanostructured layer,surface work hardening,high amplitude of residual compressive stress,and improved surface *** factors effectively prevented the initiation of fatigue crack at the surface and shifted it to the sublayer,and inhibited the subsequent crack propagation.

关键词： Ti-6Al-7Nb alloy Surface mechanical attrition treatment(SMAT) Gradient nanostructure Surface integrity Fatigue resistance

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu jun-Li Lin Jin-han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

BSA-lysozyme coated NaCa_(2)HSi_(3)O_(9)nanorods on titanium for cytocompatibility and antibacterial activity

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Journal of Materials Science & Technology 2021年第29期88卷 240-249页

作者： Yang Xue jun Chen Lan Zhang Yong han State-key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong UniversityXi'an 710049China Department of Osteology Xi'an People’s Hospital(Xi'an No.4 Hospital)Xi'an 710100China Department of Osteology Tangdu HospitalFourth Military Medical UniversityXi'an 710038China

Extracellular supplement of Ca and Si accelerates osteogenisis and angiogenisis during bone ***-based ceramics are biodegradable and can release Ca and Si ions ***,locally high alkalinity induced by excessively rapid degradation limits their *** this paper,NaCa_(2)HSi_(3)O_(9)(NCS)nanorods were fabricated on Ti by micro-arc oxidation and hydrothermal treatment;protein layers consisted of different rations of bovine serum albumin(BSA)and lysozyme(LYS)were prepared on NCS nanorods by spinning coating and thermal *** microstructure,ion releasing and wettability of coatings were observed;osteoblast and endotheliocyte behaviors,as well as bacteria response in vitro,were *** protein layer did not change microstructure and phase composition of nanorods but acted as a barrier isolating nanorods from contacting medium,and it results in slowing down the degradation of *** reduced increase of pH value,released Ca and Si ions and incorporation of LYS in BSA protein layer gave NCS nanorods improved MC3 T3-E1 and HUVECs response,compared with ***,the protein layers except pure LYS endowed nanorods with a highly antibacterial effect against staphylococcus aureus and escherichia coli simultaneously,indicating the key role of BSA in resisting antibacterial *** nanorods with BSA and LYS composited protein layers should be a potential coating applied on Ti implants for increasing osseointegration.

关键词： NaCa_(2)HSi_(3)O_(9)nanorods Bovine serum albumin Lysozyme Antibacterial activity Cytocompatibility

Pembrolizumab-induced psoriatic arthritis treated with disease-modifying anti-rheumatic drugs in a patient with gastric cancer:A case report

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World Journal of Clinical Cases 2023年第1期11卷 218-224页

作者： Sehan kim Jong Hee Sun Hongsik kim Hee Kyung kim Yaewon Yang jun Su Lee In Ah Choi Hye Sook han Department of Internal Medicine Chungbuk National University HospitalCheongju 28644South Korea Department of Gastroenterology Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505South Korea Department of Internal Medicine Chungbuk National University HospitalChungbuk National University College of MedicineCheongju 28644South Korea

BACKGROUND Immune checkpoint inhibitor(ICI)-induced rheumatic immune-related adverse events(ir AEs)have been infrequently reported,and the treatment of severe or refractory arthritis as ir AEs has not been established *** SUMMARY The patient was a 67-year-old man with a history of well-controlled foot psoriasis who presented with *** had received pembrolizumab for metastatic gastric adenocarcinoma 2 mo *** examination revealed erythematous swelling in the distal interphalangeal joints,left shoulder,and both *** had plaque psoriasis with psoriatic nail dystrophy and dactylitis in the distal joints of the fingers and *** markers including C-reactive protein and erythrocyte sedimentation rate were elevated but rheumatoid factor and anticyclic citrullinated peptide antibody were *** patient was diagnosed with psoriatic arthritis(PsA)and started on methylprednisolone 1 mg/kg/day after pembrolizumab ***,despite 1 wk of methylprednisolone treatment,PsA worsened;hence,leflunomide and methotrexate were *** 4 wk of steroid treatment,PsA worsened and improved repeatedly with steroid ***,the therapy was intensified to include etanercept,a tumor necrosis factor inhibitor,which ultimately resulted in adequate PsA *** This is the first report of ICI-induced PsA in a gastric cancer *** rheumatic ir AEs with refractory severe arthritis may require disease-modifying anti-rheumatic drugs and long-term management.

关键词： Pembrolizumab Psoriatic arthritis Disease-modifying anti-rheumatic drugs Gastric cancer Case report

Nonlinear Degenerate Parabolic Equations with Time-dependent Singular Potentials for Baouendi–Grushin Vector Fields

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Acta Mathematica Sinica,English Series 2015年第1期31卷 123-139页

作者： jun Qiang han Qian Qiao GUO Department of Applied Mathematics Northwestern Polytechnical University

In this paper, we are concerned with the following three types of nonlinear degenerate parabolic equations with time-dependent singular potentials： uq/ t=▽α·（‖z‖^-pγ｜▽αu｜^p-2▽αu）＋V（z, t）u^p-1, uq/ t=▽α·（‖z‖^-2γ▽αu^m）＋V（z, t）u^m, uq/ t=u^μ▽α·（u^τ｜▽αu｜^p-2▽αu）＋V（z, t）u^p-1＋μ＋τin a cylinder Ω×（0, T） with initial condition u（z, 0）=u0（z） ≥ 0 and vanishing on the boundary Ω×（0, T）, where Ω is a Carnot-Carathéodory metric ball in Rd＋k and the time-dependent singular potential function is V（z, t） ∈ L^1loc （Ω×（0, T））. We investigate the nonexistence of positive solutions of these three problems and present our results on nonexistence.

关键词： Nonlinear degenerate parabolic equations Baouendi-Grushin vector fields positive solu-tions~ nonexistence Hardy inequality