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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 292-310页

作者： Rendi KURNIAwan Moran XU Min Ki CHOO Shuo CHEN Yein KWAK' Jielin CHEN Saood ALI hanwei TENG pil wan han Gi Soo KIM Tae Jo KO Precision Machining Laboratory Department of Mechanical Engineering Yeungnam UniversityGyeongsansiGyeongbuk-doRepublic of Korea Korea Electrotechnology Research Institute(KERI) ChangwonsiGyeongsangnam-doRepublic of Korea KASWIN Co. LtdChangwon-siGyeongsangnamdoRepublic of Korea

This study presents the development of an ultrasonic transducer with a radius horn for an ultrasonic milling spindle(UMS)*** ultrasonic transducer was intended to have a working frequency of approximately 30 *** different materials were considered in the study:stainless steel(SS 316L)and titanium alloy(Ti-6Al-4V).Titanium alloy gave a higher resonance frequency(33 kHz)than stainless steel(30 kHz)under the same preload compression *** electromechanical impedance simulation was carried out to predict the impedance resonance frequency for both materials,and the effect of the overhanging toolbar was *** to the electromechanical impedance simulation,the overhanging toolbar length affected the resonance frequency,and the error was less than 3%.Harmonic analysis confirmed that the damping ratio helps determine the resonance ***,damping ratios of 0.015-0.020 and 0.005-0.020 were selected for stainless steel and titanium alloy,respectively,with an error of less than 1.5%.Experimental machining was also performed to assess the feasibility of ultrasonic-assisted milling;the result was a lesser cutting force and better surface topography of Al 6061.

关键词： Ultrasonic spindle Ultrasonic vibration assisted-milling(UVAM) 1-degree of freedom(DOF) Frequency Amplitude Milling

RFFsNet-SEI:a multidimensional balanced-RFFs deep neural network framework for specific emitter identification

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Journal of Systems Engineering and Electronics 2024年第3期35卷 558-574,F0002页

作者： FAN Rong SI Chengke han Yi wan Qun School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Institute of Electronic and Electrical Engineering Civil Aviation Flight University of ChinaGuanghan 618307China

Existing specific emitter identification(SEI)methods based on hand-crafted features have drawbacks of losing feature information and involving multiple processing stages,which reduce the identification accuracy of emitters and complicate the procedures of *** this paper,we propose a deep SEI approach via multidimensional feature extraction for radio frequency fingerprints(RFFs),namely,***,we extract multidimensional physical RFFs from the received signal by virtue of variational mode decomposition(VMD)and Hilbert transform(HT).The physical RFFs and I-Q data are formed into the balanced-RFFs,which are then used to train *** introducing model-aided RFFs into neural network,the hybrid-driven scheme including physical features and I-Q data is *** improves physical interpretability of ***,since RFFsNet-SEI identifies individual of emitters from received raw data in end-to-end,it accelerates SEI implementation and simplifies procedures of ***,as the temporal features and spectral features of the received signal are both extracted by RFFsNet-SEI,identification accuracy is ***,we compare RFFsNet-SEI with the counterparts in terms of identification accuracy,computational complexity,and prediction *** results illustrate that the proposed method outperforms the counterparts on the basis of simulation dataset and real dataset collected in the anechoic chamber.

关键词： specific emitter identification(SEI) deep learning(DL) radio frequency fingerprint(RFF) multidimensional feature extraction(MFE) variational mode decomposition(VMD)

Effects of Hydrogen Charging Time and Pressure on the Hydrogen Embrittlement Susceptibility of X52 Pipeline Steel Material

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 293-307页

作者： Hong-Jiang wan Xiao-Qi Wu Hong-Liang Ming Jian-Qiu wang En-Hou han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Northeastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangzhou510530China

The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile *** fracture morphologies of the specimens are observed by scanning electron *** HE susceptibility of the X52 pipeline steel material increases with an increase in both hydrogen charging time and hydrogen *** a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 ***,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.

关键词： Hydrogen embrittlement X52 pipeline steel material Tubular specimen Hydrogen charging time Hydrogen charging pressure

Recent advances in visible light-mediated chemical transformations of enaminones

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Chinese Chemical Letters 2024年第2期35卷 4-15页

作者： Yu han Liyun Zhou Chengyu wang Shangti Feng Rong Ma Jie-Ping wan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China School of Chemistry and Chemical Engineering Linyi UniversityLinyi 276000China Linyi Sanfeng Chemical Co. Ltd.Linyi 276000China

Enaminones,which possesses both the nucleophilic enamine as well as electrophilic enone structures,are well known versatile building blocks in organic ***,visible light-mediated reactions have emerged as useful synthetic strategy with enhanced *** the last decade,various photochemical transformations of enaminones have been developed to construct cyclic or acyclic *** this review,we describe the recent advances in visible light-mediated chemical transformations of *** discussion on the reaction mechanism of the related reactions is given to provide guide to the ***,a summary on the existing challenges and the future outlook towards the development of practical photocatalytic reactions of enaminones is also presented.

关键词： Enaminone Visible light C-H functionalization C=C bond cleavage Cyclization Multicomponent reactions

Compositional and Hollow Engineering of Silicon Carbide/Carbon Microspheres as High-Performance Microwave Absorbing Materials with Good Environmental Tolerance

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Nano-Micro Letters 2024年第9期16卷 128-146页

作者： Lixue Gai Yahui wang Pan wan Shuping Yu Yongzheng Chen Xijiang han Ping Xu Yunchen Du MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China Anhui Provincial Laboratory of Advanced Laser Technology College of Electronic EngineeringNational University of Defense TechnologyHefei 230037People’s Republic of China

Microwave absorbing materials(MAMs)characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical *** silicon carbide and carbon are considered as stable MAMs under some rigorous conditions,while their composites still fail to produce satisfactory microwave absorption performance regardless of the improvements as compared with the ***,we have successfully implemented compositional and structural engineering to fabricate hollow Si C/C microspheres with controllable *** simultaneous modulation on dielectric properties and impedance matching can be easily achieved as the change in the composition of these *** formation of hollow structure not only favors lightweight feature,but also generates considerable contribution to microwave attenuation *** the synergistic effect of composition and structure,the optimized SiC/C composite exhibits excellent performance,whose the strongest reflection loss intensity and broadest effective absorption reach-60.8 dB and 5.1 GHz,respectively,and its microwave absorption properties are actually superior to those of most SiC/C composites in previous *** addition,the stability tests of microwave absorption capacity after exposure to harsh conditions and Radar Cross Section simulation data demonstrate that hollow SiC/C microspheres from compositional and structural optimization have a bright prospect in practical applications.

关键词： SiC/C composites Compositional engineering Hollow engineering Microwave absorption Environmental tolerance

At-rest lateral earth pressure of compacted expansive soils:Experimental investigations and prediction approach

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1425-1435页

作者： Zhong han Pan Zhang Weilie Zou Kewei Fan Sai K.Vanapalli Lianglong wan School of Civil Engineering Wuhan UniversityWuhanChina Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering of the Ministry of Education Wuhan UniversityWuhanChina Department of Civil Engineering University of OttawaOttawaOntarioCanada Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjingChina Residence Engineering Management Station of Shenzhen Municipality ShenzhenChina

This paper presents experimental studies on a compacted expansive soil,from Nanyang,China for investigating the at-rest lateral earth pressureσL of expansive *** key studies include(i)relationships between theσL and the vertical stressσV during soaking and consolidation,(ii)the influences of initial dry densityρd0 and moisture content w 0 on the vertical and lateral swelling pressures at no swelling strain(i.e.σV0 andσL0),and(iii)evolution of theσL during five long-term wetting-drying *** results demonstrated that the post-soakingσL-σV relationships are piecewise linear and their slopes in the passive state(σL>σV)and active state(σL<σV)are similar to that of the consolidationσL-σV relationships in the normal-and over-consolidated states,*** soakingσL-σV relationships converge to the consolidationσL-σV relationships at a thresholdσV where the interparticle swelling is ***σL0 andσV0 increase monotonically withρd0;however,they show increasing-then-decreasing trends with the w *** extent of compaction-induced swelling anisotropy,which is evaluated byσL0/σV0,reduces with an increase in the compaction energy and molding water ***σL reduces over moisture cycles and the stress relaxation in theσL during soaking is *** approach was developed to predict the at-rest soakingσL-σV relationships,which requires conventional consolidation and shear strength properties and one measurement of theσL-σV relationships during *** proposed approach was validated using the results of three different expansive soils available in the literature.

关键词： Lateral earth pressure Expansive soil Soaking Vertical stress Swelling pressure

Cadaverine and putrescine exposure influence carbon and nitrogen cycling genes in water and sediment of the Yellow River

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Journal of Environmental Sciences 2024年第8期142卷 236-247页

作者： wanghong Su Qiaoling Yu Jiawei Yang Qian han Sijie wang Petr Hedenec Xiaochen wang Ruijun wan-Yan Huan Li School of Public Health Lanzhou UniversityLanzhou 730000China 2 Institute for Tropical Biodiversity and Sustainable DevelopmentUniversity Malaysia Terengganu21030Kuala NerusTerengganuMalaysia State Key Laboratory of Grassland Agro-ecosystems Center for Grassland MicrobiomeCollege of pastoral agriculture science and technology Lanzhou UniversityLanzhou 730000China

The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental ***,the response mechanisms and pathways of the functional genes associated with the carbon(C)and nitrogen(N)cycling to cadaveric substances such as cadaverine and putrescine remain *** study explored the variation of functional genes associated with C fixation,C degradation and N cycling and their influencing factors under cadaverine,putrescine and mixed *** results showed only putrescine significantly increased the alpha diversity of C fixation genes,while reducing the alpha diversity of N cycling genes in *** the C cycling,the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes(i.e.,acsB and acsE)and lig gene linked to lignin degradation in water,while only significantly increasing the hydroxypropionate-hydroxybutylate cycle(i.e.,accA)gene abundance in *** the N cycling,mixed treatment significantly decreased the abundance of the nitrification(i.e.,amoB),denitrification(i.e.,nirS3)genes in water and the assimilation pathway gene(i.e.,gdhA)in *** factors(i.e.,total carbon and total nitrogen)were all negatively associated with the genes of C and N ***,cadaverine and putrescine exposure may inhibit the pathway in C fixation and N cycling,while promoting C *** findings can offer some new insight for the management of amine pollution caused by animal cadavers.

关键词： Carbon cycling Nitrogen cycling Cadaverine Putrescine Pollution management

High-speed flexible near-infrared organic photodiode for optical communication

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National Science Review 2024年第3期11卷 227-238页

作者： Yu Zhu Hongbin Chen Ruiman han Hao Qin Zhaoyang Yao hang Liu Yanfeng Ma Xiangjian wan Guanghui Li Yongsheng Chen The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryTianjin Key Laboratory of Functional Polymer Materials College of Chemistry and Renewable Energy Conversion and Storage Center(RECAST) Nankai University State Key Laboratory of Elemento-Organic Chemistry Nankai University

Optical communication is a particularly compelling technology for tackling the speed and capacity bottlenecks in data communication in modern society. Currently, the silicon photodetector plays a dominant role in high-speed optical communication across the visible-near-infrared spectrum. However, its intrinsic rigid structure, high working bias and low responsivity essentially limit its application in next-generation flexible optoelectronic devices. Herein, we report a narrow-bandgap non-fullerene acceptor（NFA） with a remarkable π-extension in the direction of both central and end units（CH17） with respect to the Y6 series, which demonstrates a more effective and compact 3D molecular packing, leading to lower trap states and energetic disorders in the photoactive film. Consequently, the optimized solution-processed organic photodetector（OPD） with CH17 exhibits a remarkable response time of 91 ns（λ = 880 nm） due to the high charge mobility and low parasitic capacitance, exceeding the values of most commercial Si photodiodes and all NFA-based OPDs operating in self-powered mode. More significantly, the flexible OPD exhibits negligible performance attenuation（<1%） after bending for 500 cycles, and maintains 96% of its initial performance even after 550 h of indoor exposure. Furthermore, the high-speed OPD demonstrates a high data transmission rate of 80 MHz with a bit error rate of 3.5 × 10-4, meaning it has great potential in next-generation high-speed flexible optical communication systems.

关键词： flexible organic photodetector high-speed NIR organic photodetector optical communication light fidelity narrow-bandgap non-fullerene acceptors

A visual analysis approach for data imputation via multi-party tabular data correlation strategies

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 398-414页

作者： Haiyang ZHU Dongming han Jiacheng PAN Yating WEI Yingchaojie FENG Luoxuan WENG Ketian MAO Yuankai XING Jianshu LV Qiucheng wan Wei CHEN The State Key Lab of CAD&CG Zhejiang UniversityHangzhou 310058China Wuchan Zhongda Digital Technology Co. Ltd.Hangzhou 310020China Zhejiang Metals and Materials Co. Ltd.Hangzhou 310005China

Data imputation is an essential pre-processing task for data governance,aimed at filling in incomplete ***,conventional data imputation methods can only partly alleviate data incompleteness using isolated tabular data,and they fail to achieve the best balance between accuracy and *** this paper,we present a novel visual analysis approach for data *** develop a multi-party tabular data association strategy that uses intelligent algorithms to identify similar columns and establish column correlations across multiple ***,we perform the initial imputation of incomplete data using correlated data entries from other ***,we develop a visual analysis system to refine data imputation *** interactive system combines the multi-party data imputation approach with expert knowledge,allowing for a better understanding of the relational structure of the *** significantly enhances the accuracy and eficiency of data imputation,thereby enhancing the quality of data governance and the intrinsic value of data *** validation and user surveys demonstrate that this method supports users in verifying and judging the associated columns and similar rows using theirdomain knowledge.

关键词： Data governance Data incompleteness Data imputation Data visualization Interactive visual analysis

Engineered extracellular vesicles efficiently deliver CRISPR-Cas9 ribonucleoprotein(RNP)to inhibit herpes simplex virus1 infection in vitro and in vivo

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1362-1379页

作者： Yuanda wan Liren Li Ruilin Chen Jiajia han Qiyun Lei Zhipeng Chen Xiaodong Tang Wenyu Wu Shuwen Liu Xingang Yao NMPA Key Laboratory for Research and Evaluation of Drug Metabolism Guangdong Provincial Key Laboratory of New Drug ScreeningSchool of Pharmaceutical SciencesSouthern Medical UniversityGuangzhou 510515China Center of Clinical Pharmacy Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060China Key Laboratory of Infectious Diseases Research in South China(Southern Medical University) Ministry of EducationGuangzhou 510515China

Extracellular vesicles(EVs)have recently emerged as a promising delivery platform for CRISPR/Cas9 ribonucleoproteins(RNPs),owing to their ability to minimize off-target effects and immune ***,enhancements are required to boost the efficiency and safety of Cas9 RNP enrichment within *** response,we employed the Fc/Spa interaction system,in which the human Fc domain was fused to the intracellular domain of PTGFRN-Δ687 and anchored to the EV ***,the B domain of the Spa protein was fused to the C domain of cargos such as Cre or *** to the robust interaction between Fc and Spa,this method enriched nearly twice the amount of cargo within the *** loaded with spCas9 RNP targeting the HSV1 genome exhibited significant inhibition of viral replication in vitro and in ***,following neuron-targeting peptide RVG modification,the in vivo dosage in neural tissues substantially increased,contributing to the clearance of the HSV1 virus in neural tissues and exhibiting a lower off-target *** findings establish a robust platform for efficient EV-based SpCas9 delivery,offering potential therapeutic advantages for HSV1 infections and other neurological disorders.

关键词： Extracellular vesicles CRISPR/Cas9 Ribonucleoproteins PTGFRN Fc/Spa HSV1 Neuron-targeting Delivery