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AWG-based large dynamic range fiber Bragg grating interrogation system

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Optoelectronics Letters 2024年第3期20卷 129-134页

作者： li Shufeng YUAN Pei li Ke li Ting zhu lianqing Key Laboratory of the Ministry of Education for Optoelectronic Measurement technology and Instrument Beijing Information Science&Technology UniversityBeijing 100192China beijing Laboratory of Optical Fiber Sensing and System Beijing Information Science&Technology UniversityBeijing 100016China

Arrayed waveguide gratings(AWGs) are extensively employed in fiber Bragg grating(FBG) interrogation systems due to their compact size, lightweight nature, and excellent interrogation performance. The resolution and total measurement range of AWG-based FBG interrogation systems are constrained by the output properties of AWG. We proposed an AWG-based large dynamic range interrogation system. The temperature dependence of AWG is exploited to achieve continuous interrogation. The test results show that the interrogation system has a dynamic range of 28.67 nm, an interrogation accuracy better than 25 pm, and a wavelength resolution of 6 pm.

关键词： fiber waveguide AWG

Research progress on rolling superlubricity in solid lubricants

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Science china(Technological Sciences) 2024年第7期67卷 1980-1990页

作者： li PanPan li HongXuan zhu DongXiang zhu YongQi KANG FuYan WANG Wan ZHANG YaXin liU XiaoHong JI li ZHOU huiDi CHEN JianMin State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Chemical Engineering Northwest Minzu UniversityLanzhou 730030China

Superlubricity is an ideal lubrication state where friction nearly vanishes between contact interfaces. It has become one of the most important research topics and approaches owing to its significance in reducing energy consumption and preventing device failures. As an efficient and universal lubricating principle capable of achieving superlubricity, rolling lubrication has attracted widespread attention in recent years. In this review, the theoretical concept of rolling lubrication and the experimental research progress of spherical/scroll structures are summarized. The review focuses on the possibility of achieving rolling lubrication using spherical/scroll structures(such as spherical fullerenes, carbon nanotubes, and formed and constructed spherical/scroll structures). The challenges in achieving rolling lubrication are summarized, and the possibility of molecular rolling lubrication,as well as its potential applications in superlubrication, are discussed.

关键词： spherical/scroll structure rolling lubrication superlubricity fullerene

Influence of Plasma Spray Parameters on the Microstructure and Property of ZrO_2-7 wt%Y_2O_3 Coating

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稀有金属材料与工程 2012年第S1期41卷 291-295页

作者： li hui,Wang Benpeng,Wei Qi,Ji Xiaojian,li zhuoxin College of Materials Science and Engineering,beijing university and technology,beijing 100124,china beijing Univ Technol Coll Mat Sci & Engn Beijing 100124 Peoples R China

The plasma sprayed ZrO2-7 wt%Y2O3(7YSZ)coating has been widely applied in aircraft engine as a thermal barrier *** this study,the duplex TBC system(MCrAlY+7YSZ)were deposited onto 304 stainless steel substrate by *** principal spraying parameters during the deposition of 7YSZ coating were optimized by using orthogonal experimental design,including the stand-off distance,plasma power,preheating temperature and powder feeding *** influences on the coating's microstructure,adhesion and its mechanical properties were studied and the optimized parameters were finally *** results showed that the dependence of the spraying parameters on the properties of 7YSZ coating is highly correlated to the melting condition of the in-flight particles.

关键词： 7YSZ plasma spray melting condition

Multifunctional WSe_(2)/Co_(3)C composite for efficient electromagnetic absorption, EMI shielding, and energy conversion

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Nano Research 2024年第3期17卷 1655-1665页

作者： Yuhang zhu Tingting liu lin li Maosheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electron EngineeringHarbin Normal UniversityHarbin 150025China

Currently,as the electromagnetic(EM)environment becomes increasingly complex,single-function EM materials can hardly resist the increasing electromagnetic interference(EMI),and there is an urgent need to develop multifunctional EM *** this work,multifunctional WSe_(2)/Co_(3)C was prepared by simple hydrothermal *** dielectric performance and EM response were *** absorption,shielding performance,and energy conversion devices were *** tailoring the loading content,WSe_(2)/Co_(3)C can switch between EM absorption and EMI *** maximum shielding effectiveness(SE)of WSe_(2)/Co_(3)C reached 36 dB,and high reflection loss(RL)of-60.28 dB and wide effective absorption bandwidth(EAB)of 6.16 GHz can be obtained at low *** multiple EM attenuation mechanisms brought by the combination of two-dimensional(2D)WSe_(2) and magnetic Co_(3)C are considered to be the main reason for the enhanced EM attenuation *** WSe_(2)/Co_(3)C composite provides a viable candidate for developing multifunctional EM materials in 2–18 GHz.

关键词： WSe_(2) Co_(3)C electromagnetic property microwave absorption electromagnetic interference shielding energy conversion

Three‐dimensional(3D)‐printed MXene high‐voltage aqueous micro‐supercapacitors with ultrahigh areal energy density and low‐temperature tolerance

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Carbon Energy 2024年第8期6卷 36-48页

作者： Yuanyuan zhu Qingxiao Zhang Jiaxin Ma Pratteek Das liangzhu Zhang Hanqing liu Sen Wang hui li Zhong‐Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhouChina Shanghai Key Laboratory of Rare Earth Functional Materials and Education Ministry Key Laboratory of Resource Chemistry Shanghai Normal UniversityShanghaiChina university of Chinese Academy of Sciences BeijingChina Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalianChina

The rapid advancement in the miniaturization,integration,and intelligence of electronic devices has escalated the demand for customizable microsupercapacitors(MSCs)with high energy ***,efficient microfabrication of safe and high‐energy MXene MSCs for integrating microelectronics remains a significant challenge due to the low voltage window in aqueous electrolytes(typically≤0.6 V)and limited areal mass loading of MXene ***,we tackle these challenges by developing a highconcentration(18mol kg^(−1))“water‐in‐liBr”(WiB)gel electrolyte for MXene symmetric MSCs(M‐SMSCs),demonstrating a record high voltage window of 1.8 ***,additive‐free aqueous MXene ink with excellent rheological behavior is developed for three‐dimensional(3D)printing customizable all‐MXene microelectrodes on various *** the synergy of a highvoltage WiB gel electrolyte and 3D‐printed microelectrodes,quasi‐solid‐state MSMSCs operating stably at 1.8 V are constructed,and achieve an ultrahigh areal energy density of 1772μWhcm^(−2)and excellent low‐temperature tolerance,with a long‐term operation at−40℃.Finally,by extending the 3D printing protocol,M‐SMSCs are integrated with humidity sensors on a single planar substrate,demonstrating their reliability in miniaturized integrated microsystems.

关键词： 3D printing aqueous electrolyte high voltage micro‐supercapacitors MXene

Effectiveness of cardioneuroablation in different subtypes of vasovagal syncope

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Journal of Geriatric Cardiology 2024年第6期21卷 651-657页

作者： Bin TU Zi-Hao LAI Ai-Yue CHEN Zhi-Yuan WENG Si-Min CAI zhu-Xin ZHANG li-Kun ZHOU li-hui ZHENG Yan YAO Arrhythmia Center Fuwai HospitalNational Center for Cardiovascular DiseasesNational Key LaboratoryChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Cardiac Center Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina Cardiovascular Department The First Affiliated HospitalFujian Medical UniversityFujian Institute of HypertensionFujianChina Department of Cardiovascular The Second Affiliated Hospital of Zhejiang University School of MedicineZhejiangChina

BACKGROUND Cardioneuroablation(CNA)has shown encouraging results in patients with vasovagal syncope(VVS).However,data on different subtypes was *** This observational study retrospectively enrolled 141 patients[mean age:40±18 years,51 males(36.2%)]with the diagnosis of *** characteristics among different types of VVS and the outcomes after CNA were *** After a mean follow-up of 4.3±1.5 years,41 patients(29.1%)experienced syncope/pre-syncope events after ***/pre-syncope recurrence significantly differed in each subtype(P=0.04).The cardioinhibitory type of VVS had the lowest recurrence rate after the procedure(n=6,16.7%),followed by mixed(n=26,30.6%)and vasodepressive(n=9,45.0%).Additionally,a significant difference was observed in the analyses of the Kaplan-Meier survival curve(P=0.02).Syncope/pre-syncope burden was significantly reduced after CNA in the vasodepressive type(Pline deceleration capacity(DC)level than those without(7.4±1.0 ms vs.9.0±1.6 ms,P=0.01).Patients with DC<8.4 ms had an 8.1(HR=8.1,95%CI:2.2-30.0,P=0.02)times risk of syncope/pre-syncope recurrence after CNA compared to patients with DC≥8.4 ms,and this association still existed after adjusting for age and sex(HR=8.1,95%CI:2.2-30.1,P=0.02).CONCLUSIONS Different subtypes exhibit different event-free *** vasodepressive type exhibited the lowest event-free rate,but those patients with DC≥8.4 ms might benefit from CNA.

关键词： syncope subtypes diagnosis

Quantized Decoders that Maximize Mutual Information for Polar Codes

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china Communications 2024年第7期21卷 125-134页

作者： zhu Hongfei Cao Zhiwei Zhao Yuping li Dou School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China

In this paper,we innovatively associate the mutual information with the frame error rate(FER)performance and propose novel quantized decoders for polar *** on the optimal quantizer of binary-input discrete memoryless channels(BDMCs),the proposed decoders quantize the virtual subchannels of polar codes to maximize mutual information(MMI)between source bits and quantized *** nested structure of polar codes ensures that the MMI quantization can be implemented stage by *** results show that the proposed MMI decoders with 4 quantization bits outperform the existing nonuniform quantized decoders that minimize mean-squared error(MMSE)with 4 quantization bits,and yield even better performance than uniform MMI quantized decoders with 5 quantization ***,the proposed 5-bit quantized MMI decoders approach the floating-point decoders with negligible performance loss.

关键词： maximize mutual information polar codes quantization successive cancellation decoding

Upgraded durian genome reveals the role of chromosome reshuffling during ancestral karyotype evolution,lignin biosynthesis regulation,and stress tolerance

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Science china(life Sciences) 2024年第6期67卷 1266-1279页

作者： Wanwan li Xin Chen Jianing Yu Yuxian zhu College of life Sciences Shaanxi Normal UniversityXi’an 710119China The State Key Laboratory of Protein and Gene Research College of Life SciencesPeking UniversityBeijing 100871China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

Durian(Durio zibethinus)is a tropical fruit that has a unique flavor and *** occupies a significant phylogenetic position within the Malvaceae *** core-eudicot plants are reported to share seven ancestral karyotypes that have undergone reshuffling,resulting in an abundant genomic ***,the ancestral karyotypes of the Malvaceae family,as well as the evolution trajectory leading to the28 chromosomes in durian,remain poorly ***,we report the high-quality assembly of the durian genome with comprehensive comparative genomic *** analyzing the collinear blocks between cacao and durian,we inferred 11 Malvaceae ancestral *** blocks were present in a single-copy form in cacao and mainly in triplicates in durian,possibly resulting from a recent whole genome triplication(WGT)event that led to hexaploidization of the durian genome around 20(17–24)million years ago.A large proportion of the duplicated genes in durian,such as those involved in the lignin biosynthesis module for phenylpropane biosynthesis,are derived directly from whole genome duplication,which makes it an important force in reshaping its genomic *** studies have revealed that genes involved in feruloyl-Co A formations were highly preferentially expressed in fruit peels,indicating that the thorns produced on durian fruit may comprise guaiacyl and syringyl *** all the analyzed transcription factors(TFs),members of the heat shock factor family(HSF)were the most significantly upregulated under heat *** subfamilies of genes encoding heat shock proteins(HSPs)in the durian genome appear to have undergone *** potential interactions between HSF Dzi05.397 and HSPs were examined and experimentally *** study provides a high-quality durian genome and reveals the reshuffling mechanism of ancestral Malvaceae chromosomes to produce the durian *** also provide insights into the mechanism underlying lignin bi

关键词： Durio zibethinus whole genome duplication whole genome triplication Malvaceae ancestral karyotypes chromosome reshuffling lignin biosynthesis heat stress

Synergistically enhanced dielectric, insulating and thermally conductive performances of sandwich PMMA based dielectric films

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Progress in Natural Science:Materials International 2024年第3期34卷 591-597页

作者： Dongmei Zhang Yufan li Yuchao li Zhonggui Sun Hanxue zhu Lujia Yang Yanhu Zhan Yankai li Shi Wang Jun-Wei Zha School of Mathematical Sciences Liaocheng University School of Materials Science and Engineering Liaocheng University State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications School of Chemistry and Biological Engineering University of Science and Technology Beijing

A tri-layered(B-G-B) dielectric films were simply prepared by alternatively spin-coating boron nitride/polymethylmethacrylate(BN/PMMA, B) and graphene nanosheets(GNS/PMMA, G) compound solutions. The structure, morphology, thermal conductivity, and particularly the dielectric and relaxation behaviors were systematically studied. Results showed that a good exfoliation and dispersion of BN and GNS can be simply achieved through intensive mechanical compounding with PMMA in the internal mixer. The dielectric constant and breakdown strength of the obtained 1-3-1(B-G-B) sandwich composite film reached 4.3(@1 kHz) and 458.6kV/mm, being 119 % and 113 % higher than that of pure PMMA, respectively. Furthermore, the overall thermal conductivity of sandwich 1-3-1 composite increased by 112 % due to the addition of thermally conductive BN and GNS. The sandwich design strategy provided an effective way of achieving good permittivity, high insulation, and improved thermal conductivity simultaneously, showing potential applications in the miniaturization and integration of electronic devices.

关键词： Breakdown strength Composites Dielectric constant Sandwich structure Thermal conductivity