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Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

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Nuclear Science and Techniques 2024年第4期35卷 1-14页

作者： Dong Zhao Xu-wen Liang Ping-Kun Cai Wei Cheng wen-bao jia Da-Qian Hei Qing Shan Yong-Sheng Ling Chao Shi Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of jiangsu Higher Education Institutions Suzhou 215000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a *** this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)*** imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded *** EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager *** difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position *** position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 *** DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution *** unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image *** method can effectively reduce image noise caused by poor DOI detector position *** vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关键词： Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging

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基于宽度网络架构的单模型主导联邦学习

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计算机系统应用 2024年第1期33卷 1-10页

作者：文家宝陈泯融华南师范大学计算机学院广州510631

联邦学习是一种分布式机器学习方法,它将数据保留在本地,仅将计算结果上传到客户端,从而提高了模型传递与聚合的效率和安全性.然而,联邦学习面临的一个重要挑战是,上传的模型大小日益增加,大量参数多次迭代,给通信能力不足的小型设备带... 详细信息

联邦学习是一种分布式机器学习方法,它将数据保留在本地,仅将计算结果上传到客户端,从而提高了模型传递与聚合的效率和安全性.然而,联邦学习面临的一个重要挑战是,上传的模型大小日益增加,大量参数多次迭代,给通信能力不足的小型设备带来了困难.因此在本文中,客户端和服务器被设置为仅一次的互相通信机会.联邦学习中的另一个挑战是,客户端之间的数据规模并不相同.在不平衡数据场景下,服务器的模型聚合将变得低效.为了解决这些问题,本文提出了一个仅需一轮通信的轻量级联邦学习框架,在联邦宽度学习中设计了一种聚合策略算法,即FBL-LD.算法在单轮通信中收集可靠的模型并选出主导模型,通过验证集合理地调整其他模型的参与权重来泛化联邦模型.FBL-LD利用有限的通信资源保持了高效的聚合.实验结果表明,FBL-LD相比同类联邦宽度学习算法具有更小的开销和更高的精度,并且对不平衡数据问题具有鲁棒性.

关键词：联邦学习宽度网络单轮通信隐私保护机器学习

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Improved formation density measurement using controllable D-D neutron source and its lithological correction for porosity prediction

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Nuclear Science and Techniques 2022年第1期33卷 24-34页

作者： Li Zhang Hua-Wei Yu Yang Li wen-bao jia Xiao Han Xue-Sen Geng College of Resources Shandong University of Science and TechnologyTai’an 271019China School of Geosciences China University of PetroleumQingdao 266580China College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018China Department of Nuclear Science and Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Controllable D-D neutron sources have a long service life,low cost,and *** are favorable prospects for its application in geophysical well logging,since traditional chemical radioactive sources used for well logging pose potential threats to the safety of the human body and *** paper presents an improved method to measure formation density that employs a D-D neutron *** addition,the lithological effect on the measured density was removed to better estimate the formation ***,we investigated the spatial distribution of capture gamma rays through Monte Carlo simulations as well as the relationship between the ratio of capture gamma ray counts and formation density to establish theoretical support for the design of density logging tools and their corresponding data processing ***,we obtained the far to near detector counts of captured gamma rays for an optimized tool structure and then established its correlation with the density and porosity of three typical formations with pure quartz,calcite,and dolomite ***,we determined the values for correcting the densities of sandstone and dolomite with the same porosity using limestone data as the reference and established the equations for calculating the correction values,which lays a solid foundation for accurately calculating formation *** observed that the capture gamma ray counts first increased then decreased and varied in different formations;this was especially observed in high-porosity *** the same lithologic conditions(rock matrix),as the porosity increases,the peak value of gamma ray counts moves toward the neutron *** different detector-source distances,the ratio of the capture gamma ray counts was well correlated with the formation *** equation of the formation density conversion was established based on the ratio of capture gamma ray counts at the detector-source distances of 30 cm and 65 cm,and the calculate

关键词： Density measurement D-D neutron source Lithological correction Porosity prediction

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Detection of heavy metals in aqueous solution using PGNAA technique

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Nuclear Science and Techniques 2016年第1期27卷 8-12页

作者： Can Cheng Da-Qian Hei wen-bao jia Zhou jiang Hong-Tao Wang Department of Nuclear Science and Engineering College of Materials Science and EngineeringNanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of jiangsu Higher Education Institutions Suzhou 215000China

A prompt gamma neutron activation analysis setup was developed for heavy metal detection in aqueous solutions with a 300 m Ci241Am-Be neutron source and a4 4 inch(diameter height) BGO detector. In the present work, heavy metals, including Mn, Cu, Ni, Cr and Zn, were measured by the setup. The minimum detectable concentrations of Mn, Cu, Ni, Cr and Zn were 246.6, 391.2, 218.1,301.5 and 2804.1 ppm, respectively. The minimum detectable concentration of each element and the linearity response between the characteristic peak counts and elements concentrations have been studied. And the results showed that all heavy metals had a good linear relationship between characteristic peak counts and concentrations.

关键词：重金属检测水溶液 PGNAA 最低检出浓度技术 BGO探测器计数方法分析装置

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Determination of thickness of wax deposition in oil pipelines using gamma-ray transmission method

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Nuclear Science and Techniques 2018年第8期29卷 121-125页

作者： Can Cheng wen-bao jia Da-Qian Hei Shu-Qun Geng Hong-Tao Wang Li-Teng Xing College of Astronautics Nanjing University of Aeronauticsand AstronauticsNanjing 211106China College of Materials Science and Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of jiangsu Higher Education Institutions Suzhou 215000China jiangsu Institute of Metrology Nanjing 210023China

Wax deposition in pipelines is a crucial problem in the oil *** approach that combines the gammaray transmission method with scanning technology is proposed to detect the thickness of wax *** performance of the method is validated through simulations with MCNP *** experiment is also carried out with a 300 mCi ^(137)Cs source and a LaBr_3 detector.A good correspondence is observed between the simulation and experimental *** results indicate that the approach is efficient for detecting the thickness of wax deposition in oil pipelines.

关键词：传播方法油管道 gamma 厚度蜡光线扫描技术 MCNP

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Application of in-situ characterization techniques in modern aqueous batteries

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Rare Metals 2024年第8期43卷 3553-3575页

作者： jia-Hao Wu Hong-Wei Cai Zhao-Hui Deng Jean-Jacques Gaumet Yu bao wen Luo Department of Physics State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingSchool of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China Laboratoire de Chimie Et Physique:Approche Multi-Echelles Des Milieux Complexes(LCP-A2MC)Institut Jean BarriolUniversitéde Lorraine57070MetzFrance Department of Medicinal Chemistry Hubei College of Chinese MedicineJingzhou 434020China

The development of high-performance aqueous batteries calls for an in-depth knowledge of their chargedischarge redox and failure mechanism,as well as a systematic understanding of the dynamic evolution of microstructure,phase composition,chemical composition,and local chemical environment of the materials for ***-situ characterization technology is expected to understand and reveal the problems faced by aqueous rechargeable batteries,such as the dissolution of electrode materials,the growth of metal negative electrode dendrites,passivation,corrosion,side reactions and a series of *** on this,typical in-situ characterization techniques and their basic mechanisms are summarized,including in-situ optical visualization,in-situ microscopy techniques(in-situ scanning electron microscopy(SEM),in-situ transmission electron microscopy(TEM)),in-situ X-ray techniques(in-situ X-ray diffraction(XRD),in-situ X-ray photoelectron spectroscopy(XPS),in-situ near-edge structural X-ray absorption spectroscopy(XANES)),and in-situ spectroscopy techniques(in-situ Raman spectroscopy,in-situ Fourier transform infrared(FTIR)).Moreover,some emerging techniques concerning aqueous battery research,especially gas evolution and materials dissolution issues,such as in-situ electrochemical quartz crystal microbalance(EQCM).in-situ fiber-optic sensing,in-situ gas chromatography(GC) are *** last,the applications of advanced in-situ characterizations in future research of aqueous batteries are emphasized and discussed,along with some of the remaining challenges and possible solutions.

关键词： Aqueous battery In-situ characterization Phase transformation Solid electrolyte interphase Zinc dendrite growth

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Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第9期42卷 990-996页

作者： Bin Lu Feng-Shuo bao Zi-Wei He wen-Jing Xiao jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CzIPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

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Barrier Option Pricing in Regime Switching Models with Rebates

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 849-861页

作者： Yue-xu ZHAO jia-yong bao School of Economics Hangzhou Dianzi UniversityHangzhou 310018China School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China

This paper is concerned with the valuation of single and double barrier knock-out call options in a Markovian regime switching model with specific *** integral formulas of the rebates are derived via matrix Wiener-Hopf factorizations and Fourier transform techniques,also,the integral representations of the option prices are ***,the first-passage time density functions in two-state regime model are *** applications,several numerical algorithms and numerical examples are presented.

关键词： option pricing Markovian regime switching Wiener-Hopf factorization Fourier transform

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Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia wen Yan Yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable *** also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal *** this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal ***,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity *** by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

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Novel MIP gene mutation causes autosomal-dominant congenital cataract

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 454-465页

作者： Jing-Lan Ni Hua-Ming wen Xiao-Sheng Huang Qian-wen Li jia-Min Cai bao-jian Fan Jun Zhao The Second Clinical Medical College Jinan UniversityShenzhen 518020Guangdong ProvinceChina Department of Ophthalmology Dongguan Chang’an HospitalDongguan 523843Guangdong ProvinceChina Shenzhen Eye Hospital Affiliated to Jinan University Shenzhen Eye InstituteShenzhen 518040Guangdong ProvinceChina Department of Oral&Maxillofacial Surgery Shenzhen Stomatology Hospital Affiliated to Shenzhen UniversityShenzhen 518040Guangdong ProvinceChina Department of Neurosurgery Massachusetts General Hospital and Harvard Medical SchoolBoston 02114MassachusettsUSA Department of Ophthalmology Shenzhen People’s Hospital(the Second Clinical Medical CollegeJinan Universitythe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina

●AIM:To identify disease-causative mutations in families with congenital cataract.●METHODS:Two Chinese families with autosomaldominant congenital cataract(ADCC)were recruited and underwent comprehensive eye *** panel next-generation sequencing of common pathogenic genes of congenital cataract was performed in the proband of each *** sequencing was used to valid the candidate gene mutations and sequence the other family members for co-segregation *** effect of sequence changes on protein structure and function was predicted through bioinformatics *** intrinsic protein(MIP)-wildtype and MIP-G29R plasmids were constructed and microinjected into zebrafish single-cell stage *** embryonic lens phenotypes were screened using confocal microscopy.●RESULTS:A novel heterozygous mutation(c.85G>A;p.G29R)in the MIP gene was identified in the proband of one family.A known heterozygous mutation(c.97C>T;p.R33C;rs864309693)in MIP was found in the proband of another ***-silico prediction indicated that the novel mutation might affect the MIP protein *** embryonic lens was uniformly transparent in both wild-type PCS2+MIP and mutant PCS2+MIP.●CONCLUSION:Two missense mutations in the MIP gene in Chinese cataract families are identified,and one of which is *** findings expand the genetic spectrum of MIP mutations associated with *** functional studies suggest that the novel MIP mutation might not be a gain-of-function but a loss-of-function mutation.

关键词： congenital cataract major intrinsic protein missense mutation zebrafish model

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