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Distribution of oxide inclusions in H13 castings under super-gravity field with multi-stage rotation speeds

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Journal of Iron and Steel Research(International) 2024年第1期31卷 121-133页

作者： Shao-ying Li Xiao-jun Xi Xing-ming zhao han-jie Guo Jing Guo School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Beijing Beiye Functional Materials Corporation Beijing100192China Shandong Tianwu Forming Technology Co. Ltd.Liaocheng252024ShandongChina

The 42 kg industrial H13 castings were prepared by different super-gravity fields with multi-rotation speeds,and the distribution of oxide inclusions in the castings was studied.In addition,the inward movement Reynolds number and inward movement time of oxide inclusions as well as the solidification time of molten steel at different positions in the castings were calculated to clarify the removal mechanism of oxide inclusions in super-gravity field.The results show that the large size(i.e.,greater than 10μm)oxide inclusions are mainly concentrated in the inner and outer parts of the super-gravity castings with constant rotation speed(500 r min^(-1))and five-stage rotation speeds(500,600,750,850,and 950 r min^(-1)),respectively,while there are no large oxide inclusions in the super-gravity castings with three-stage rotation speeds(500,600,and 750 r min^(-1)).Although an increase in the particle size of inclusion and the rotation speed in super-gravity field is conducive to the increase in the inward movement Reynolds number of oxide inclusions and reduction in the inward movement time of oxide inclusions,it will reduce the local solidification time of molten steel.In the range of the rotation speed studied,the super-gravity field with three-stage rotation speeds has the best effect on the removal of inclusions in H13 molten steel.

关键词： Distribution Oxide inclusion H13 casting Super-gravity field Rotation speed

High-entropy oxide-supported platinum nanoparticles for efficient hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1537-1546页

作者： Ming-Yu Fan Jia-jun Wang jun zhao Hong Zhang Tian-Yi Ma Xiao-Peng han Wen-Bin Hu School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Key Laboratory of Advanced Ceramics and Machining Technology Tianjin University School of National University of Singapore and Tianjin University International Campus of Tianjin University School of Science RMIT University

High-entropy oxides（HEOs） are a new class of single-phase structures with unique electronic and catalytic properties;therefore,it is worthwhile to explore their applications in electrocatalysis.In this study,a Pt/（FeCoNiCrAl）3O4nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction（HER）.Pt/（FeCoNiCrAl）3O4exhibited high HER activity with a low overpotential of 22 mV at10 mA·cm-2,outperforming other binary,ternary,and quaternary supports.The HER activity of Pt/（FeCoNiCrAl）3O4was higher than that of a commercial Pt/C with a significantly lower Pt loading.The catalyst exhibited good activity and long-term stability（60 h） in an electrolytic water-splitting device.This good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the HEO.In addition,the HEO substrate was more favorable for dispersing Pt particles,optimizing the electrochemical specific surface area,and significantly reducing the charge resistance of the HER.This study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.

关键词： High-entropy oxides Hydrogen evolution reaction Nanohybrid Water electrolysis

Clinical usefulness of the baby vision test in young children and its correlation with the Snellen chart

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 348-352页

作者： Ya-Lan Wang Jia-jun Wang Xi-Cong Lou han Zou Yun-E zhao The Eye Hospital of Wenzhou Medical University Hangzhou 310000Zhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Wenzhou 325027Zhejiang ProvinceChina

AIM:To investigate the efficacy of a new visual acuity(VA)screening method,the baby vision test for young children.METHODS:A total 105 eyes of 65 children aged 2-8y were included in the study.Acuity testing was conducted using a standardized recognition acuity chart(Snellen visual chart:at 3 m)and the baby vision model assessment.The baby vision device includes a screen,a near infrared camera and a computer.Children were seated at a measured distance of 33-40 cm from a display for testing.VA was estimated according to the highest resolution the children could follow.Decimal VA data were converted to logarithm of the minimum angle of resolution(logMAR)for statistical analysis.The VA results for each child were recorded and analyzed for consistency.RESULTS:The mean VA measured using the Snellen visual chart was 0.62±0.32,and that assessed using the baby vision test was 0.66±0.27.The 95%limit of agreement was-0.609 to 0.695,with 95.2%(100/105)plots within the 95%limits of agreement.VA values of the baby vision test were significantly correlated with those of the Snellen chart(R=0.274,P=0.005).CONCLUSION:The baby vision test can be used as a relatively reliable method for estimating VA in young children.This new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children.

关键词： baby vision test acuity assessment fix-and-follow system Snellen chart

Random Raman Fiber Laser as a Liquid Refractive Index Sensor

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Photonic Sensors 2024年第1期14卷 13-22页

作者： Bing han Yuxi MA han WU Yong zhao College of Information Science and Engineering Northeastern UniversityShenyang 110819China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao 066004China College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China

In this paper,a new concept of forward-pumped random Raman fiber laser(RRFL)-based liquid refractive index sensing is proposed for the first time.For liquid refractive index sensing,the flat fiber end immersed in the liquid can act as the point reflector for generating random fiber lasing and also as the sensing head.Due to the high sensitivity of the output power of the RRFL to the reflectivity provided by the point reflector in the ultralow reflectivity regime,the proposed RRFL is capable of achieving liquid refractive index sensing by measuring the random lasing output power.We theoretically investigate the effects of the operating pump power and fiber length on the refractive index sensitivity for the proposed RRFL.As a proof-of-concept demonstration,we experimentally realize high-sensitivity half-open short-cavity RRFL-based liquid refractive index sensing with the maximum sensitivity and the sensing resolution of-39.88W/RIU and 2.5075×10^(-5) RIU,respectively.We also experimentally verify that the refractive index sensitivity can be enhanced with the shorter fiber length of the RRFL.This work extends the application of the random fiber laser as a new platform for highly-sensitive refractive index sensing in chemical,biomedical,and environmental monitoring applications,etc.

关键词： Fiber optic sensors refractive index measurements fiber lasers Rayleigh scattering stimulated Raman scattering

Safflower Yellow Inhibits Progression of Hepatocellular Carcinoma by Modulating Immunological Tolerance via FAK Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 339-347页

作者： JI Hua-feng YANG Zi-qiang han jun-jun LI He-fang JIN zhao-qing CHEN Wei-qing CHEN Fei-hua GONG Mou-chun Department of General Surgery First People's Hospital of Hangzhou Lin'an DistrictHangzhou(311300)China

Objective To explore the anti-tumor effect of safflower yellow(SY)against hepatocellular carcinoma(HCC)and the underlying potential mechanism.Methods An in vitro model was established by mixing Luc-Hepa1-6 cells and CD3^(+)CD8^(+)T cells,followed by adding programmed cell death protein 1(PD-1)antibody(Anti-mPD-1)with or without SY.The apoptosis was detected by flow cytometry and the level of inflammatory cytokines was determined by enzyme-linked immunosorbent assay.The protein levels of programmed cell death 1 ligand 1(PD-L1),chemokine ligand(CCL5),C-X-C motif chemokine ligand 10(CXCL10)were measured by Western blot.An in situ animal model was established in mice followed by treatment with anti-mPD-1 with or without SY.Bioluminescence imaging was monitored with an AniView 100 imaging system.To establish the FAK-overexpressed Luc-Hepa1-6 cells,cells were transfected with adenovirus containing pcDNA3.1-FAK for 48 h.Results The fluorescence intensity,apoptotic rate,release of inflammatory cytokines,and CCL5/CXCL10 secretion were dramatically facilitated by anti-mPD-1(Phanced by SY(Phanced by SY(Phanced effects of SY on inhibiting tumor cell growth,facilitating apoptosis and inflammatory cytokine releasing,suppressing the PD-1/PD-L1 axis,and inducing the CCL5/CXCL10 secretion in Anti-mPD-1 treated mixture of Luc-Hepa1-6 cells and CD3+CD8+T cells were abolished by FAK overexpression(P<0.01).Conclusion SY inhibited the progression of HCC by mediating immunological tolerance through inhibiting FAK.

关键词： hepatocellular carcinoma safflower yellow Chinese medicine tumor microenvironment programmed cell death protein 1 focal adhesion kinase

Advanced Sensors Towards Ubiquitous Power Internet of Things

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 871-890页

作者： Jinliang He Zhifei han jun Hu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China IEEE CSEE

The ubiquitous power Internet of Things(UPIoT)uses modern information technology and advanced communication technologies to realize interconnection and human-computer interaction in all aspects of the power system.UPIoT has the characteristics of comprehensive state perception and efficient information processing,and has broad application prospects for transformation of the energy industry.The fundamental facility of the UPIoT is the sensor-based information network.By using advanced sensors,Wireless Sensor Networks(WSNs),and advanced data processing technologies,Internet of Things can be realized in the power system.In this paper,a framework of WSNs based on advanced sensors towards UPIoT is proposed.In addition,the most advanced sensors for UPIoT purposes are reviewed,along with an explanation of how the sensor data obtained in UPIoT is utilized in various scenarios.

关键词： Advanced sensors ubiquitous power Internet of Things wireless sensor networks

A novel small-signal equivalent circuit model for GaN HEMTs incorporating a dual-field-plate

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Journal of Semiconductors 2024年第5期45卷 61-68页

作者： Jinye Wang jun Liu Zhenxin zhao School of Integrated Circuit Science and Engineering Hangzhou Dianzi UniversityHangzhou 310018China

An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(HEMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a source-FP.The equivalent circuit of the overall model is composed of parasitic elements,intrinsic transistors,gate-FP,and source-FP networks.The equivalent circuit of the gate-FP is identical to that of the intrinsic transistor.In order to simplify the complexity of the model,a series combination of a resistor and a capacitor is employed to represent the source-FP.The analytical extraction procedure of the model parameters is presented based on the proposed equivalent circuit.The verification is carried out on a 4×250μm GaN HEMT device with a gate-FP and a source-FP in a 0.45μm technology.Compared with the classic model,the proposed novel small-signal model shows closer agreement with measured S-parameters in the range of 1.0 to 18.0 GHz.

关键词： small-signal model dual field-plate(FP) GaN high-electron-mobility transistors(HEMT) parameter extraction

A Simple Proof of ACC for Minimal Log Discrepancies for Surfaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 425-434页

作者： Jing jun han Yu Jie LUO Shanghai Center for Mathematical Sciences Fudan UniversityJiangwan CampusShanghai 200438P.R.China Department of Mathematics Johns Hopkins UniversityBaltimoreMD 21218USA

Following Shokurov's idea,we give a simple proof of the ACC conjecture for minimal log discrepancies for surfaces.

关键词： Ascending chain condition minimal log discrepancies minimal model program surface

Ten-year observation of corneal densitometry and associated factors following small incision lenticule extraction

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 485-490页

作者： Xiao-Song han Fei Xia Zhuo-Yi Chen Pei-jun Yao Dong-Mei Yang Jing zhao Xing-Tao Zhou Eye Institute and Department of Ophthalmology Eye&ENT HospitalFudan UniversityShanghai 200031China NHC Key Laboratory of Myopia(Fudan University) Key Laboratory of MyopiaChinese Academy of Medical SciencesShanghai 200031China Shanghai Research Center of Ophthalmology and Optometry Shanghai 200031China Shanghai Engineering Research Center of Laser and Autostereoscopic 3D for Vision Care(20DZ2255000) Shanghai 200031China

●AIM:To investigate the long-term changes of corneal densitometry(CD)and its contributing elements after small incision lenticule extraction(SMILE).●METHODS:Totally 31 eyes of 31 patients with mean spherical equivalent of-6.46±1.50 D and mean age 28.23±7.38y were enrolled.Full-scale examinations were conducted on all patients preoperatively and during followup.Visual acuity,manifest refraction,axial length,corneal thickness,corneal higher-order aberrations,and CD were evaluated.●RESULTS:All surgeries were completed successfully without complications or adverse events.Ten-year safety index was 1.17±0.20 and efficacy 1.04±0.28.CD value of 0–6 mm zones in central layer was statistically significantly lower 10y postoperatively,compared with preoperative values(0–2 mmΔ=-1.62,2–6 mmΔ=-1.24,Phanism is to be further discussed.

关键词： myopia small incision lenticule extraction corneal densitometry