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Communications in Theoretical physics 2024年第5期76卷 114-127页

作者： Sourav Chaudhary Jitendra Kumar S K Maurya Sweeti Kiroriwal Abdul Aziz Department of Mathematics Central University of HaryanaJant-PaliMahendergarhIndia Department of Mathematical and physical sciences College of Arts and ScienceUniversity of NizwaP.O.Box 33Nizwa 616Oman

In this work,we have explored wormhole(WH)solutions in F(R,L_(m))gravity by assuming the Morris-Thorne WH metric and F(R,Lm)=R/2+(1+γR)L_(m),whereγis the free model *** determined the WH solutions by utilizing two newly developed shape functions(SF)that satisfy all basic conditions for a WH’s physical *** also observe that the null energy condition(NEC)behaves ***,for both models,we use the volume integral quantifier(VIQ)and Tolman-oppenheimer-Volkoff(ToV)equation to determine how much exotic matter is needed near the WH throat and the stability of the *** extensive detailed discussions of the matter components have been done via graphical *** obtained WH geometries meet the physically acceptable conditions for a stable wormhole.

关键词： energy conditions wormhole exotic matter F(R L_(m))gravity

Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils

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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun Zhu Fu-San Chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese academy of sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Development of 400-μW cryogen-free dilution refrigerators for quantum experiments

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Chinese physics b 2024年第7期33卷 28-35页

作者：关翔樊洁边勇波程智刚姬忠庆 Institute of physics Chinese Academy of SciencesBeijing 100190China School of physical sciences University of Chinese Academy of SciencesBeijing 100190China

We have successfully developed cryogen-free dilution refrigerators with medium cooling power that can be applied to quantum experiments. breakthroughs have been made in some key technologies and components of heat switches and dilution units. our prototype has been running continuously and stably for more than 100 hours below 10 m K, with a minimum temperature of 7.6 m K and a cooling power of 450 μW at 100 m K. At the same time, we have also made progress in the application of dilution refrigerators, such as quantum computing, low-temperature detector, and magnet integration. These indicators and test results indicate good prospects for application in physics, astronomy, and quantum information.

关键词： cryogen-free dilution refrigerator quantum computing low-temperature detector superconducting magnet

Two thin middle-crust low-velocity zones imaged in the Chuan-Dian region of southeastern Tibetan plateau and their tectonic implications

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Science China Earth sciences 2024年第5期67卷 1675-1686页

作者： Long LI Xin WANG Guangbing HoU Yuan LING Yinshuang AI Key Laboratory of Earth and planetary physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and planetary sciences University of Chinese Academy of SciencesBeijing 100049China Innovation academy for Earth Science Chinese Academy of SciencesBeijing 100029China

Intracrustal low-velocity zones(LVZs)indicate a mechanically weak crust and are widely observed in the southeast margin of the Tibetan ***,their spatial distributions and formation mechanisms remain *** investigate their distribution and detailed morphology of the LVZs in the southeastern Tibetan plateau,here we used teleseismic events and continuous waveform data recorded by 40 broadband seismic stations newly deployed in the Sichuan-Yunnan region from December 2018 to october 2020.A total of 12,924 high-quality p-wave receiver functions and 5–40 s fundamental Rayleigh surface wave phase velocity dispersion curves from ambient noise cross-correlation functions were *** Swave velocity model at a depth interval of 0–100 km in the study area was inverted by using the trans-dimensional Markov chain Monte Carlo strategy to jointly invert the complementary data of the receiver function waveform and Rayleigh surface wave phase velocity *** results show that there are two separate LVZs(~3.5 km/s)surrounding the rigid Daliangshan subblock at crustal depths of approximately 30–40 km,providing new constraints on the geometry of the LVZs in our study *** two LVZs obtained in this study may represent the middle crustal flow channels,through which the material in the center of the Tibetan plateau extrudes to its southeast *** by the rigid Sichuan basin and the spindle-like Daliangshan subblock,the material continues to flow southward through the mechanically weak middle crustal channels surrounding the Daliangshan *** addition,the existence of thin LVZs in the middle crust plays an important role in understanding the decoupling between the upper and lower crust in the study *** also provides new constraint on the complex tectonic deformation process of the southeastern margin of the Tibetan plateau caused by the collision and compression of the Indian and the Eurasian plates.

关键词： Southeastern Tibetan plateau Joint inversion Intracrustal low-velocity zone Mid-crustal channel flow

Exhaustive review of acceleration strategies for Monte Carlo simulations in photon transit

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Journal of Innovative optical Health sciences 2024年第5期17卷 5-21页

作者： Louzhe Xu Zijie Zhu Ting Li Institute of biomedical Engineering Chinese academy of Medical sciences&peking Union Medical College Tianjin 300192 P.R.China

Monte Carlo simulation techniques have become the quintessence and a pivotal nexus of inquiry in the realm of simulating photon movement within biological *** the stochastic sampling of tissue archetypes delineated by explicit optical characteristics,Monte Carlo simulations possess the theoretical capacity to render unparalleled accuracy in the depiction of exceedingly intricate ***,the quintessential challenge associated with Monte Carlo simulation methodologies resides in their extended computational duration,which significantly impedes the re¯nement of their ***,this discourse is speci¯cally dedicated to exploring innovations in strategies and technologies aimed at expediting Monte Carlo *** delves into the foundational concepts of various acceleration tactics,evaluates these strategies concerning their speed,accuracy,and practicality,and amalgamates a comprehensive overview and critique of acceleration methodologies for Monte Carlo ***,the discourse envisages prospective trajectories for the employment of Monte Carlo techniques within the domain of tissue optics.

关键词： Medical optics photon transport simulation Monte Carlo simulation acceleration

Literature classification and its applications in condensed matter physics and materials science by natural language processing

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Chinese physics b 2024年第5期33卷 117-123页

作者：吴思远朱天念涂思佳肖睿娟袁洁吴泉生李泓翁红明 Institute of physics Chinese Academy of SciencesBeijing 100190China School of physical sciences University of Chinese Academy of SciencesBeijing 100190China College of Materials Science and optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China Condensed Matter physics Data Center of Chinese academy of sciences Beijing 100190China

The exponential growth of literature is constraining researchers’access to comprehensive information in related *** natural language processing(NLp)may offer an effective solution to literature classification,it remains hindered by the lack of labelled *** this article,we introduce a novel method for generating literature classification models through semi-supervised learning,which can generate labelled dataset iteratively with limited human *** apply this method to train NLp models for classifying literatures related to several research directions,i.e.,battery,superconductor,topological material,and artificial intelligence(AI)in materials *** trained NLp‘battery’model applied on a larger dataset different from the training and testing dataset can achieve F1 score of 0.738,which indicates the accuracy and reliability of this ***,our approach demonstrates that even with insufficient data,the not-well-trained model in the first few cycles can identify the relationships among different research fields and facilitate the discovery and understanding of interdisciplinary directions.

关键词： natural language processing text mining materials science

A Certified Cubic b-Spline Interpolation Method with Tangential Direction Constraints

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Journal of Systems Science & Complexity 2024年第3期37卷 1271-1294页

作者： HE Shitao SHEN Liyong WU Qin YUAN Chunming School of Mathematical sciences University of Chinese Academy of SciencesBeijing 100049China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

Curve interpolation with b-spline is widely used in various areas. This problem is classic and recently raised in application scenario with new requirements such as path planning following the tangential vector field under certified error in CNC machining. This paper proposes an algorithm framework to solve Hausdorff distance certified cubic b-spline interpolation problem with or without tangential direction constraints. The algorithm has two stages: The first stage is to find the initial cubic b-spine fitting curve which satisfies the Hausdorff distance constraint;the second stage is to set up and solve the optimization models with certain constraints. Especially, the sufficient conditions of the global Hausdorff distance control for any error bound are discussed, which can be expressed as a series of linear and quadratic constraints. A simple numerical algorithm to compute the Hausdorff distance between a polyline and its b-spline interpolation curve is proposed to reduce our *** results are presented to show the advantages of the proposed algorithms.

关键词： Cubic b-spline Hausdorff distance interpolation tangential direction

Genetic dissection and validation of a major QTL for grain weight on chromosome 3b in bread wheat(Triticum aestivum L.)

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Journal of Integrative Agriculture 2024年第1期23卷 77-92页

作者： Simin Liao Zhibin Xu Xiaoli Fan Qiang Zhou Xiaofeng Liu Cheng Jiang Liangen Chen Dian Lin bo Feng Tao Wang Chengdu Institute of biology Chinese Academy of SciencesChengdu 610041China University of Chinese academy of sciences Beijing 100049China The Innovative academy of Seed Design Chinese Academy of SciencesBeijing 100101China

Grain weight is one of the key components of wheat(Triticum aestivum L.)*** manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six *** major QTLs,***-2D,***-2D,***-3b,***-4b.1,***-2D.1,***-2D.1 and ***-3b.1,were consistently identified in at least four environments and the best linear unbiased estimation(bLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic *** interactions were detected between the two major TGW QTLs and three major GW *** addition,***-3b.1 and ***-3b were co-located,and the improved TGW at this locus was contributed by *** other loci,***-3b.1/***-3b had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific pCR(KASp)markers,and a comparison analysis indicated that ***-3b.1/***-3b is likely a novel *** haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and *** to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of ***-3b.1/***-3b was ***,the major QTLs and KASp markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement.

关键词： thousand-grain weight QTL mapping haplotype analysis candidate gene

observation of parabolic electron bands on superconductor LaRu2As2

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Chinese physics b 2024年第7期33卷 70-75页

作者：周兴泰李更潘禄禄陈子超李萌时延昊杨海涛高鸿钧 beijing National Center for Condensed Matter physics and Institute of physics Chinese Academy of Sciences School of physical sciences University of Chinese Academy of Sciences Hefei National Laboratory

Ru-based superconductor LaRu2As2has been discovered exhibiting the highest critical temperature of ～ 7.8 K among iron-free transition metal pnictides with the ThCr2Si2-type crystal structure. However, microscopic research on this novel superconducting material is still lacking. Here, we utilize scanning tunneling microscopy/spectroscopy to uncover the superconductivity and surface structure of LaRu2As2. Two distinct terminating surfaces are identified on the cleaved crystals, namely, the As surface and the La surface. Atomic missing line defects are observed on the La surface. both surfaces exhibit a superconducting gap of ～ 1.0 me V. by employing quasiparticle interference techniques, we observe standing wave patterns near the line defects on the La atomic plane. These patterns are attributed to quasiparticle scattering from two electron type parabolic bands.

关键词： superconductivity line defect quasi-particle scattering electron band

A Disulfide-based poly(ether-b-amide)Copolymer with Rapid Self-healing Ability under Moderate Conditions

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Chinese Journal of Chemistry 2024年第9期42卷 943-950页

作者： Weijan Lu ping Zhu Ying Zhao Dujin Wang Xia Dong Institute of Chemistry Chinese Academy of SciencesBeijing 100190China Schoolof Chemical sciences University of Chinese Academy of SciencesBeijing 100049China

Comprehensive Summary A disulfide-based poly(ether-b-amide)copolymer with rapid self-healing capability under moderate conditions was synthesized from 4,4’-dithiodibutyric acid(DTDbA),isophorondiamine(IpDA)and poly(tetramethylene oxide)(pTMo)based on a two-step *** incorporation of IpDA with asymmetric structure and substantial steric hindrance not only effectively decreased the number of regular H-bonds,but also inhibited the crystallization of polyamide segments,imparting the synthesized poly(ether-b-amide)copolymer with an amorphous structural *** on the coordination of segmental diffusion and recombination of disulfide bonds and hydrogen bonds,the scratches and damaged mechanical properties of pEbADS-I611 could be completely self-healed after healing at 40°C for only 11 min and 3 h,respectively.

关键词： poly(ether-b-amide)copolymer Disulfide bonds Hydrogen bonds polycondensation Smart polymers Self-healing