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Chinese Physics C 2024年第10期48卷 176-184页

作者： Anshul Dadwal Xiao-Tao he Department of Nuclear Science and Technology College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

A variable moment of inertia(VMI)inspired interacting boson model(IBM),which includes many-body interactions and a perturbation possessing(5)(or(5))symmetry,is used to investigate the rotational bands of the mass region.A novel modification is introduced,extending the Arima coefficient to the third *** study is dedicated to the quantitative analysis of evolving trends in intrabandγ-transition energy as well as the kinematic and dynamic moments of inertia(MoIs)within the rotational bands of^(244)Pu and^(248)*** computed outcomes exhibit an exceptional degree of agreement with experimental observations across various *** significance of including a higher-order Arima coefficient is further examined by contrasting it with the previously proposed *** calculated results demonstrate the significance of both the anti-pairing and pairing effects in the evolution of the dynamic ***,these insights reveal the importance of a newly introduced parameter in accurately depicting complex nuclear behaviors,such as back-bending,up-bending,and downturn in the MoI.

关键词： rotational bands nuclear structure back-bending up-bending 250 mass region

非典型大西洋尼诺对中国东部前、后汛期降水的影响

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大气科学学报 2024年第2期47卷 260-272页

作者：杨萌洲袁潮霞南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心/气候与应用前沿研究院江苏南京210044 日本海洋研究开发机构应用实验室日本横滨2360001

采用1979—2020年共42 a的降水观测和再分析资料,使用多变量EOF、傅立叶滤波、线性回归、T-N波通量等方法,研究了非典型大西洋尼诺(Non-Canonical Atlantic Ni1o,NCA)对中国东部夏季前、后汛期降水的影响及物理机制。结果显示,NCA在前... 详细信息

采用1979—2020年共42 a的降水观测和再分析资料,使用多变量EOF、傅立叶滤波、线性回归、T-N波通量等方法,研究了非典型大西洋尼诺(Non-Canonical Atlantic Ni1o,NCA)对中国东部夏季前、后汛期降水的影响及物理机制。结果显示,NCA在前汛期引起中国南方降水增加,但在后汛期导致华南沿海地区降水减少而北方降水增加。这是由于在前汛期,NCA的暖海温异常位于热带北大西洋,可通过“风-蒸发-海表温度”正反馈引起拉尼娜,进而激发西北太平洋异常反气旋,其西北侧的异常西南气流有助于将暖湿水汽输送至我国南方,导致前汛期南方降水增加。在后汛期,NCA的暖海温异常南移至赤道大西洋,通过调节沃克环流增强拉尼娜,使得西北太平洋异常反气旋进一步增强并覆盖华南地区,导致华南降水减少而北方降水增加。此外,与NCA相关的东传罗斯贝波列在前/后汛期位于副热带/中高纬地区,其在我国东部引起的环流异常也有助于NCA在前/后汛期影响我国南/北方降水。

关键词：非典型大西洋尼诺(NCA) 中国东部前、后汛期降水

β-C(sp^(3))−H chlorination of amide derivatives via photoinduced copper charge transfer catalysis

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Chinese Chemical Letters 2024年第2期35卷 361-365页

作者： Yuhang he Chao Tian Guanghui An Guangming Li Key Laboratory of Functional Inorganic Material Chemistry (MOE) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

An atom economicβ-C(sp^(3))−H chlorination of amide derivatives has been *** mild protocol employs CuCl_(2) instead of palladium catalysts with atom-economic HCl as chlorine sources and enables the late-stage functionalization of medicine *** studies suggest a plausible visible light triggered ligand-to-metal charge transfer(LMCT)/1,4-hydrogen atom transfer(HAT)cascade.

关键词： Photoinduced copper catalysis Ligand-to-metal charge transfer 1,4-Hydrogen atom transfer β-Halogenated amide Late-stage functionalization

Gravitational waves and primordial black hole productions from gluodynamics by holography

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 31-42页

作者： Song he Li Li Zhibin Li Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Golm 14476Germany CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

Understanding the nature of quantum chromodynamics(QCD)matter is important but challenging due to the presence of nonperturbative dynamics under extreme *** construct a holographic model describing the gluon sector of QCD at finite temperatures in the non-perturbative *** equation of state as a function of temperature is in good accordance with the lattice QCD ***,the Polyakov loop and the gluon condensation,which are proper order parameters to capture the deconfinement phase transition,also agree quantitatively well with the lattice QCD *** obtain a strong first-order confinement/deconfinement phase transition at Tc=276.5 Me V that is consistent with the lattice QCD *** on our model for a pure gluon hidden sector,we compute the stochastic gravitational waves and primordial black hole(PBH)productions from this confinement/deconfinement phase transition in the early *** resulting stochastic gravitational-wave backgrounds are found to be within detectability in the International Pulsar Timing Array and Square Kilometre Array in the near future when the associated productions of PBHs saturate the current observational bounds on the PBH abundances from the LIGO-Virgo-Collaboration O3 data.

关键词： AdS/QCD confinement/deconfinement phase transition gravitational wave primordial black hole

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

Centennial Analysis of Human Activity Intensity and Associated Historical Events in heilongjiang River Sino-Russo Watershed

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Chinese Geographical Science 2024年第2期34卷 280-293页

作者： SONG Chaoxue LI Xiaoling he Hongshi Michael SUNDE School of Geographical Sciences Northeast Normal UniversityChangchun 130024China School of Natural Resources University of MissouriColumbia 65211USA

Human activities in a transborder watershed are complex under the influence of domestic policies,international relations,and global *** the forces driving human activity change is important for the development of transborder *** this study,we used global historical land cover data,the hemeroby index model,and synthesized major historical events to analyze how human activity intensity changed in the heilongjiang River(Amur River in Russia)watershed(HLRW).The results showed that there was a strong spatial heterogeneity in the variation of human activity intensity in the HLRW over the past century(1900-2016).On the Chinese side,the human activity intensity change shifted from the plain areas for agricultural reclamation to the mountainous areas for timber *** the Russian side,human activity intensity changes mostly concentrated along the Trans-Siberian Railway and the Baikal-Amur *** variation of human activity intensity tended to respond to regional events while regionalized variation tends to reflect national policy change or broad international *** similarities and differences between China and Russia in policies and positions in international events resulted in synchronous and asynchronous changes in human activity ***,policy shifts were often confined by the natural features of the *** results reveal the historical origins and fundamental connotations of watershed development and contribute to formulating regional management policies that coordinate population,eco-nomic,social,and environmental activities.

关键词： human activity intensity changes hemeroby index centennial scale heilongjiang River(Amur River in Russia)watershed China Russia

Ecological Network Resilience of Shiyang River Basin: An Arid Inland Watershed of Northwest China

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Chinese Geographical Science 2024年第5期34卷 951-966页

作者： he Yangxi LIU Chunfang NI Bowen LIAN Hugang School of Management Northwest Normal UniversityLanzhou 730070China Research Center of Land Use and Comprehensive Improvement Engineering of Gansu Province Lanzhou 730070China

Due to the uncertainties posed by climate change,resilience has become an increasingly important variable for evaluating regional ecosystem *** assessment of Ecological Network Resilience(ENR)is crucial for establishing mitigation strategies and sustainable socioeconomic development in arid *** River Basin is an arid watershed in Northwest China with complex characteristics,its ENR and spatial differentiation characteristics in 2020 were investigated in this work based on the Complex Adaptive System(CAS)*** results indicated that the mean Ecological Network Resilience Index(ENRI)value for the Shiyang River Basin was 0.390 in 2020,and the mean values in the southern mountainous,middle oasis,and northern desert regions of the basin were 0.598,0.461,and 0.237,respectively,demonstrating evident spatial ***,the ENR of the basin exhibited distinct distribution characteristics across different dimension,whereas the trend of the integrated ENR of the basin was consistent with that of elemental,structural,and functional resilience,indicating the constructed three-region ENR model based on the logical relationship of element-structure-function was suitable for evaluation of the ENR in arid inland river ***,strategies for enhancing regional ENR were proposed from the perspective of adapting to climate change.

关键词： Ecological Network Resilience(ENR) Complex Adaptive System(CAS) element-structure-function Shiyang River Basin Northwest China

An ensemble learning method to retrieve sea ice roughness from Sentinel-1 SAR images

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Acta Oceanologica Sinica 2024年第5期43卷 78-90页

作者： Pengyi Chen Zhongbiao Chen Runxia Sun Yijun he School of Marine Sciences Nanjing University of Information Science&TechnologyNanjing 210044China East Sea Information Center of State Oceanic Administration Shanghai 200136China

Sea ice surface roughness(SIR)affects the energy transfer between the atmosphere and the ocean,and it is also an important indicator for sea ice *** obtain a small-scale SIR with high spatial resolution,a novel method is proposed to retrieve SIR from Sentinel-1 synthetic aperture radar(SAR)images,utilizing an ensemble learning ***,the two-dimensional continuous wavelet transform is applied to obtain the spatial information of sea ice,including the scale and direction of ice ***,a model is developed using the Adaboost Regression model to establish a relationship among SIR,radar backscatter and the spatial information of sea *** proposed method is validated by using the SIR retrieved from SAR images and comparing it to the measurements obtained by the Airborne Topographic Mapper(ATM)in the summer Beaufort *** determination of coefficient,mean absolute error,root-mean-square error and mean absolute percentage error of the testing data are 0.91,1.71 cm,2.82 cm,and 36.37%,respectively,which are ***,K-fold cross-validation and learning curves are analyzed,which also demonstrate the method’s applicability in retrieving SIR from SAR images.

关键词： 2-D Cauchy continuous wavelet transform(CWT) Adaboost Regression sea ice sea ice surface roughness

An improved algorithm for retrieving thin sea ice thickness in the Arctic Ocean from SMOS and SMAP L-band radiometer data

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Acta Oceanologica Sinica 2024年第3期43卷 127-138页

作者： Lian he Senwen Huang Fengming Hui Xiao Cheng School of Geospatial Engineering and Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-Sen University) Ministry of EducationZhuhai 519082China

The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer *** SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice *** relationship between the SIT and PR was found to be almost stable across the five selected *** SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction *** results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT *** proposed algorithm can be used for thin sea ice thickness(he Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical.

关键词： Arctic sea ice sea ice thickness remote sensing Soil Moisture Active Passive(SMAP) Soil Moisture Ocean Salinity and Soil(SMOS)

Excavation compensation and bolt support for a deep mine drift

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3206-3220页

作者： Longji Guo Zhigang Tao Manchao he Massimo Coli State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics&Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China Department of Earth Sciences University of FlorenceFirenze50121Italy

To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 130 KN was *** the conducted tests,the amount of deformation was 200-2000 mm,the breaking force reached 350 KN,and a high constant-resistance pre-stress was maintained during the deformation process.A stress compensation theory of phosphate rock excavation based on NPR bolts is proposed together with a balance system for bolt compensation of the time-space effect and high NPR *** split-set rock bolts are unable to maintain the stability of roadway roofs and *** verify the support effect of the proposed bolt,field tests were conducted using both the proposed NPR bolts and split-set rock bolts as support systems on the same mining *** addition,the stress compensation mechanism of roadway mining was simulated using the particle flow code in three dimensions(PFC^(3D))-fast Lagrangian analysis of continua(FLAC^(3D))particle-flow coupling numerical ***-site monitoring and numerical simulations showed that the NPR excavation compensation support scheme effectively improves the stress state of the bolts and reduces the deformation of the surrounding *** to the original support scheme,the final deformation of the surrounding rock was reduced by approximately 70%.These results significantly contribute to domestic and foreign research on phosphate-rock NPR compensation support technology,theoretical systems,and engineering practices,and further promote technological innovation in the phosphate rock mining industry.

关键词： Deep phosphate rock NPR bolt Split-set rock bolt PFC3D-FLAC3D Compensation support