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Nuclear Science and Techniques 2023年第10期34卷 91-102页

作者： Yuan-Qiao Li Bao-Ji zhu Yang Lv Heng zhu Min Lin ke-Sheng Chen Li-jun Xu China Institute of Atomic Energy Beijing 102413China National key Laboratory for Metrology and Calibration Techniques Beijing 102413China

To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN) algorithms: back-propagation(BP) and genetic algorithm-based back-propagation(GA-BP). These algorithms classify pulse signals from distinct α and β particles. Their discrimination efficacy is assessed by simulating standard pulse signals and those produced by contaminated sources, mixing α and β particles within the detector. This study initially showcases energy spectrum measurement outcomes, subsequently tests the ANNs on the measurement and validation datasets, and contrasts the pulse shape discrimination efficacy of both algorithms. Experimental findings reveal that the proportional counter's energy resolution is not ideal, thus rendering energy analysis insufficient for distinguishing between 2πα and 2πβ particles. The BP neural network realizes approximately 99% accuracy for 2πα particles and approximately 95% for 2πβ particles, thus surpassing the GA-BP's performance. Additionally, the results suggest enhancing β particle discrimination accuracy by increasing the digital acquisition card's threshold lower limit. This study offers an advanced solution for the 2πα and 2πβ surface emission rate measurement method, presenting superior adaptability and scalability over conventional techniques.

关键词： Pulse shape discrimination Artificial neural networks Alpha and beta sources Multi-wire proportional counter Surface emission rate

High thermoelectric properties realized in earth abundant Bi_(2)S_(3) bulk materials via Se and Cl co-doping in solution synthesis process

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Journal of Materials Science & Technology 2022年第5期100卷 51-58页

作者： jun Guo Yu-ke zhu Lin Chen Zi-Yuan Wang Zhen-Hua Ge Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Bi_(2)S_(3)-based alloys are considered promising thermoelectric materials due to their large Seebeck coefficient and low lattice thermal ***,low electrical conductivity usually leads to poor electrical transport properties,which seriously restricts their further application in thermoelectric refrigeration and/or power *** this work,Bi_(2)S_(3) with high electrical transport properties is synthesized hydrothermally via Se and Cl *** maximum electrical conductivity value of 483 S cm^(-1) was obtained for the Bi_(2)S_(2.4)Se_(0.4)Cl_(0.20) sample at room *** significant improvement of electrical conductivity gives rise to a high average power factor of 411μW m^(-1) K^(-2) during the measuring temperature range and a peak value of 456μW m^(-1) K^(-2) at 673 *** from the largely improved electrical transport properties,a superior ZT value of approximately 0.66 and *** 0.36 were obtained for Bi_(2)S_(2.4)Se_(0.4)Cl_(0.20),and the theoretically calculated conversion efficiency reached 5.7%.The results indicate that Bi_(2)S_(3) is a promising candidate for thermoelectric applications at medium temperatures.

关键词： Bismuth sulfide Electrical conductivity Doping Thermal conductivity

Synergistically enhanced thermoelectric properties of Bi_(2)S_(3) bulk materials via Cu interstitial doping and BiCl_(3) alloying

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Rare Metals 2022年第3期41卷 931-941页

作者： jun Guo Zi-Yuan Wang Yu-ke zhu Lin Chen Jing Feng Zhen-Hua Ge Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Bi_(2)S_(3)is composed of inexpensive and environ-mental friendliness elements,which has received extensive interests and been investigated as a promising mid-tempera-ture thermoelectric material for *** pure Bi_(2)S_(3)pos-sesses a high Seebeck coefficient and low thermal conductivity,its low electrical conductivity leads to a lowfigure of merit(ZT)*** this work,Bi_(2)S_(3)fabricated by solid-state melting combined with spark plasma sintering can significantly enhance the thermoelectric performance via introducing small amounts of Cu and BiCl_(3).Cu interstitial doping and Cl substitution on S site result in a large increase in electrical ***,the enhanced phonon scattering is derived from the point defects caused by element doping,the grain boundaries,and the small amount of sec-ondary phase,which leads to the low thermal ***,a high ZT value of 0.7 is obtained at 773 K and reaches a large average ZT of 0.36 in the temperature range from room temperature(RT)to 773 K for the Cu-interstitial-doped and BiCl_(3)-alloyed(Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3))***,the mechanical properties of the Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3)sample are lower than those of other Bi_(2)S_(3)samples,which stem from the weak chemical bonding strength.

关键词： Bismuth sulfide Cu–Cl co-doping Electrical conductivity Mechanical properties

Effect of Phase Separation Size on the Properties of Self-healing Elastomer

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Chinese Journal of Polymer Science 2024年第6期42卷 798-804页

作者： jun Xu Lei zhu Xian-Qi Feng Cong Sui Wen-Peng Zhao Shou-ke Yan School of Chemical Engineering Qingdao University of Science&TechnologyQingdao266042China College of Engineering Yanching institute of TechnologyLangfang065210China key Laboratory of Rubber-plastics Qingdao University of Science&TechnologyQingdao266042China State key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Regulation of phase structure has been recognized as one of the most effective ways to fabricate self-healing polymers with high mechanical *** mechanical properties of the resultant polymers are certainly affected by the size of separated phase ***,the study on this aspect is absence,because it can hardly exclude the influence of variation in monomer proportion required for tuning the separated phase ***,we report the first study on tuning the phase size through reversible addition-fragmentation chain transfer(RAFT)polymerization without changing the proportion of *** expected,the size of separated phase has been successfully mediated from 15 nm to 9 nm by tuning the molecular weight of the chain transfer *** is found that the mechanical strength and the self-healing efficiency of the resultant polymers increase simultaneously with the decrease of phase *** study on the formation kinetics of hydrogen bonds reveals that the decrease of phase size can facilitate the re-bonding rate of hydrogen bonds,even if the migration of polymer chains is restricted.

关键词： Self-healing polymers Phase separation Reversible addition-fragmentation chain transfer

Synthesis and Characterization of Easily Colored Meta-aramid Copolymer Containing Ether Bonds

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Chinese Journal of Polymer Science 2019年第3期37卷 227-234页

作者： Na Li Xing-ke Zhang jun-Rong Yu Yan Wang Jing zhu Zu-Ming Hu State key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University

This work described the preparation of easily colored meta-aramid(PMIA) copolymers from m-phenylenediamine(MPD),isophthaloyl dichloride(IPC), and 3,4′-oxydianiline(3,4′-ODA) via solution polycondensation in N,N-dimethylacetamide(DMAc). The novel co-PMIAs were obtained in relatively high inherent viscosities ranging from 1.32 dL/g to 2.53 dL/g, which could be easily cast into flexible films with high transparence or spun into fibers. All the newly synthesized copolymers possessed excellent thermal stabilities even better than that of commercial PMIA, with 5% weight loss temperatures higher than 430 °C in nitrogen measured by TGA and glass transition temperature of 267–277 °C measured by DSC. The cast films exhibited good mechanical properties with a tensile strength up to107 MPa and a tensile modulus up to 2.2 GPa. The resultant PMIAs also showed good solubility and better dye ability for cationic dyes.

关键词： Copolymerized meta-aramid Solution polycondensation Dyeability

Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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Science China Life Sciences 2025年第1期 144-157页

作者： Huanbo zhu Longtao Huangfu junbing Chen Jiafu Ji Xiaofang Xing key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute Department of Gastrointestinal Cancer Center Peking University Cancer Hospital & Institute Department of Liver Surgery & Transplantation Liver Cancer InstituteZhongshan HospitalFudan University key Laboratory of Carcinogenesis and Cancer Invasion Ministry of Education State key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute

Extrachromosomal DNA(ecDNA) is a form of circular DNA mostly found in tumor cells. Unlike the typical chromosomal DNA, ecDNA is circular, self-replicating, and carries complete or partial gene fragments. Although ecDNA occurrence remains a rare event in cancer, recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer, implying that ecDNA plays a central role in accelerating tumor evolution. ecDNA has also been associated with increased tumor mutation burden, chromosomal instability, and even tumor microenvironment remodeling. ecDNA may be crucial in influencing tumor heterogeneity, drug sensitivity,oncogenic senescence, and tumor immunogenicity, leading to a worsening prognosis for tumor patients. In this way, several clinical trials have been conducted to investigate the importance of ecDNA in clinical treatment. In this review, we summarize the biogenesis, characteristics, and current research methods of ecDNA, discuss the vital role of ecDNA-caused tumor heterogeneity in cancers, and highlight the potential role of ecDNA in cancer therapy.

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Increased Hydrogen-bonding of Poly(m-phenylene isophthalamide) (PMIA) with Sulfonate Moiety for High-performance Easily Dyeable Fiber

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Chinese Journal of Polymer Science 2020年第11期38卷 1230-1238,I0008页

The demand for high thermal stability and high strength agents is growing steadily as a result of their increasing application in advanced materials.A series of sulfonated poly(m-phenyleneisophthalamide)(SPMIA)copolymers with superior thermal stability and good mechanical properties have been prepared via low temperature polycondensation *** the structures of 5PMA copolymers with different content quantities of 2,4-diaminobenzenesulfonic acid(2,4-DABSA)were confimed by Fourier transform infrared(FTiR).Besides,their superior thermal properties were systematically investigated by differential canning calorimetry DSC),thermalgravimetreic analysis(TGA),and dynamic mechanical analysis(DMA).SPMA fbers were obtained by wet spinning using the resultant SPMIAsolutions.n addition,the obtained SPMIA fibers were proved to combine enhanced mechanical properties and unprecedented ***,the SPMlA iber with great mechanical property,thermal stability,and dyeability shows great potential in easily dyeing high-performance protective fibers.

关键词： Sulfonated polyim-phenyleneisophthalamide) Copolymer Sulfonic acid group High-Performance fiber Eaily dyeable fiber

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding Zhe Sui Hong Su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

Defect Engineering with Rational Dopants Modulation for High-Temperature Energy Harvesting in Lead-Free Piezoceramics

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Xi, Kaibiao Guo, Jianzhe Zheng, Mupeng zhu, Mankang Hou, Yudong Beijing Univ Technol Coll Mat Sci & Engn Key Lab Adv Funct Mat Minist Educ Beijing 100124 Peoples R China

High temperature piezoelectric energy harvester (HT-PEH) is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors. However, simultaneously excellent performances, including high figure of merit (FOM), insulation resistivity (rho) and depolarization temperature (T-d) are indispensable but hard to achieve in lead-free piezoceramics, especially operating at 250 degrees C has not been reported before. Herein, well-balanced performances are achieved in BiFeO3-BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping. Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization, regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole, comprehensive excellent electrical performances (T-d = 340 degrees C, rho(250) (degrees C) > 10(7) Omega cm and FOM2(50 degrees C) = 4905 x 10(-15 )m(2) N-1) are realized at the solid solubility limit of manganese ions. The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250 degrees C with high energy conversion efficiency (eta = 11.43%). These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements, paving a new way in developing self-powered wireless sensors working in HT environments.

关键词： Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester

Computed tomography-guided chemical renal sympathetic nerve modulation in the treatment of resistant hypertension: A case report

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World Journal of Clinical Cases 2021年第32期9卷 9970-9976页

作者： Ge Luo Jian-jun zhu Ming Yao ke-Yue Xie Department of Anesthesiology and Pain The Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Resistant hypertension(RH)has always been a difficult problem in clinical diagnosis and *** present,there is no recognized safe and effective minimally invasive *** SUMMARY An 80-year-old woman was admitted to hospital due to trigeminal neuralgia(TN).The patient had a history of RH for more than 10 years and her blood pressure(BP)was not *** the treatment for TN,we decided to perform chemical renal sympathetic denervation with ethanol in the Pain Department of our *** year after the operation,she stopped taking antihypertensive drugs,and her BP was satisfactorily controlled within 4 years after *** Computed tomography-guided chemical renal sympathetic modulation may be a feasible method for the treatment of RH.

关键词： Resistant hypertension Renal sympathetic denervation Ethanol Case report