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High-order time-reversal symmetry breaking normal state

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： Meng Zeng Lun-hui hu Hong-Ye hu Yi-Zhuang You Congjun Wu Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA Department of Physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional *** two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type Z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap *** contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is *** phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is *** θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal *** both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry *** employ an effective two-component XY-model assisted by a renormalization group analysis to address this *** a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)*** is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature Z_(2)-breaking charge-2e superconducting *** results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

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Dynamic interwell connectivity analysis of multi-layer waterflooding reservoirs based on an improved graph neural network

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Petroleum Science 2024年第2期21卷 1062-1080页

作者： Zhao-Qin huang Zhao-Xu Wang hui-Fang hu Shi-Ming Zhang Yong-Xing Liang Qi Guo Jun Yao School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Exploration and Development Research Institute Shengli OilfieldSINOPECDongying257015ShandongChina

The analysis of interwell connectivity plays an important role in the formulation of oilfield development plans and the description of residual oil distribution. In fact, sandstone reservoirs in China's onshore oilfields generally have the characteristics of thin and many layers, so multi-layer joint production is usually adopted. It remains a challenge to ensure the accuracy of splitting and dynamic connectivity in each layer of the injection-production wells with limited field data. The three-dimensional well pattern of multi-layer reservoir and the relationship between injection-production wells can be equivalent to a directional heterogeneous graph. In this paper, an improved graph neural network is proposed to construct an interacting process mimics the real interwell flow regularity. In detail, this method is used to split injection and production rates by combining permeability, porosity and effective thickness, and to invert the dynamic connectivity in each layer of the injection-production wells by attention *** on the material balance and physical information, the overall connectivity from the injection wells,through the water injection layers to the production layers and the output of final production wells is established. Meanwhile, the change of well pattern caused by perforation, plugging and switching of wells at different times is achieved by updated graph structure in spatial and temporal ways. The effectiveness of the method is verified by a combination of reservoir numerical simulation examples and field example. The method corresponds to the actual situation of the reservoir, has wide adaptability and low cost, has good practical value, and provides a reference for adjusting the injection-production relationship of the reservoir and the development of the remaining oil.

关键词： Graph neural network Dynamic interwell connectivity Production-injection splitting Attention mechanism Multi-layer reservoir

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Astronomic background of global huge earthquakes at beginning of 21st century

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Applied Geophysics 2024年第3期21卷 423-432,616页

作者： hu hui Su You-Jin Yunnan Observatory Chinese Academy of SciencesKunming 650011China Seismological Bureau of Yunnan Province Kunming 650224China

Since the beginning of the 21st century,major earthquakes have frequently occurred *** explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is used to systematically analyze the effects of astronomical factors,such as solar activity,Earth’s rotation,lunar declination angle,celestial tidal force,and other phenomena on M≥8 global earthquakes at the beginning of the 21st *** regard to solar activity,this study focuses on the analysis of the 11-year and century cycles of solar *** causal relationship of the Earth’s rotation is not obvious in this work and previous works;in contrast,the valley period of the solar activity century cycle may be an important astronomical factor leading to the frequent occurrence of global earthquakes at the beginning of the 21st *** topic warrants further study.

关键词： M≥8.0 earthquake astronomical factors solar activity Earth’s rotation lunar declination angle tidal force phenomena

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Patterns and drivers of avian taxonomic and phylogenetic beta diversity in China vary across geographical backgrounds and dispersal abilities

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Zoological Research 2024年第1期45卷 125-135页

作者： Jian-Chao Liang Zhi-Feng Ding Chun-Lin Li Yi-Ming hu Zhi-Xin Zhou Gan-Wen Lie Xiao-Nan Niu Wen-Bin huang hui-Jian hu Xing-Feng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong 510260China School of Resources and Environmental Engineering Anhui UniversityHefeiAnhui 230601China Guangdong Eco-Engineering Polytechnic GuangzhouGuangdong 510520China huizhou Institute of Forestry(huizhou Botanical Garden Management Service Center) HuizhouGuangdong 516001China Administration of National Nature Reserve for Marine Ecology of Guangdong Nanpeng Islands ShantouGuangdong 515900China Zhejiang Zhoushan Archipelago Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity ***,we examined whether the patterns and drivers of taxonomic beta diversity(TBD)and phylogenetic beta diversity(PBD)of breeding birds in China vary across(1)regions on both sides of the hu Line,which demarcates China’s topographical,climatic,economic,and social patterns,and(2)species with different dispersal *** and PBD were calculated and partitioned into turnover and nestedness components using a moving window *** representing climate,habitat heterogeneity,and habitat quality were employed to evaluate the effects of environmental *** distance was considered to assess the impact of dispersal *** partitioning analysis was applied to assess the relative roles of these *** general,the values of TBD and PBD were high in mountainous areas and were largely determined by environmental ***,different dominant environmental filters on either side of the hu Line led to divergent beta diversity ***,climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line,***,bird species with stronger dispersal ability were more susceptible to environmental filtering,resulting in more homogeneous *** results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns,and dispersal ability determines the response of assemblages to these ecological *** a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete ***,a comprehensive understanding of large-scale beta diversity patterns and effective pla

关键词： Beta diversity Environmental filtering Dispersal limitation hu Line Species dispersal ability Breeding birds

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Construction of metal-organic frameworks with unsaturated Cu sites for efficient and fast reduction of nitroaromatics:A combined experimental and theoretical study

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Chinese Chemical Letters 2024年第8期35卷 514-519页

作者： Longlong Geng huiling Liu Wenfeng Zhou Yong-Zheng Zhang Hongliang huang Da-Shuai Zhang hui hu Chao Lv Xiuling Zhang Suijun Liu Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou 253023China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China State Key Laboratory of Separation Membranes and Membrane Processes School of Chemical Engineering and TechnologyTiangong UniversityTianjin 300387China School of Chemistry and Chemical Engineering Jiangxi Provincial Key Laboratory of Functional Molecular Materials ChemistryJiangxi University of Science and TechnologyGanzhou 341000China

Metal-organic frameworks(MOFs)functionalized with open metal sites(OMSs)have received widespread attention in various applications due to their fascinating electronic properties and unique interactions with guest ***,rational tailoring of the coordination environment of metal nodes dur-ing the synthesis of MOFs remains a great challenge due to their tendency of saturated coordination with ***,we reported the construction of three new MOFs featuring unsaturated Cu(Ⅱ)sites,namely[Cu(HCOO)(pzta)]_(n)(HL-1),{[Cu(PTA)0.5(pzta)(H_(2)O)]·2H_(2)O}_(n)(HL-2)and[Cu(NA)0.5(pzta)]_(n)(HL-3)(Hpzta=3-pyrazinyl-1,2,4-triazole;PTA=terephthalic acid;NA=1,4-naphthalene dicarboxylic acid),based on the mixed-linker strategy via specific selection of versatile Hpzta ligand and carboxylate ***-markably,the obtained MOFs exhibited excellent activity and good recyclability for the catalytic reduction of nitroaromatics under mild conditions(25℃and 1 atm).In particular,the complete conversion of 4-nitrophenol(4-NP)took only 30 s on HL-2,reaching a record-high TOF value compared with previously reported metal *** combined experimental and theoretical studies on HL-2 revealed that the open Cu site with positive-charged nature could improve the adsorption and subsequent electron trans-port between the substrates,and was responsible for the outstanding *** work shined lights on the further enhancement of performance for MOFs through rational OMSs construction.

关键词： Metal-organic frameworks Open metal sites Catalysis Copper node 4-Nitrophenol

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Relative peripheral refraction in school children with different refractive errors using a novel multispectral refraction topographer

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1477-1482页

作者： hui-Ling hu Serena Zhe-Chuang Li Ai-Ying Feng Hao-Xi Zhong Jing-Feng Mu Mei-Zhou Liu Shenzhen Eye Hospital Jinan UniversityShenzhen Eye InstituteShenzhen 518040Guangdong ProvinceChina NIMO Ophthalmology Research Institute Beijing 100176China

AIM:To compare relative peripheral refraction(RPR)in Chinese school children with different refractive errors using multispectral refraction topography(MRT).METHODS:A total of 713 eyes of primary school children[172 emmetropia(E),429 low myopia(LM),80 moderate myopia(MM),and 32 low hypermetropia(LH)]aged 10 to 13y were *** were measured using MRT without *** results showed RPR at 0-15°(RPR 0-15),15°-30°(RPR 15-30),and 30°-45°(RPR 30-45)annular in the inferior(RPR-I),superior(RPR-S),nasal(RPR-N),and temporal(RPR-T)*** equivalent(SE)was detected and calculated using an ***:There were significant differences of RPR 15-30 between groups MM[0.02(-0.12;0.18)]and LH[-0.13(-0.36;0.12)](P<0.05),MM and E[-0.06(-0.20;0.10)](P<0.05),and LM[-0.02(-0.15;0.15)]and E(P<0.05).There were also significant differences of RPR 30-45 between groups MM[0.45(0.18;0.74)]and E[0.29(-0.09;0.67)](P<0.05),and LM[0.44(0.14;0.76)]and E(P<0.001).RPR values increased from the hyperopic to medium myopic group in each *** were significant differences of RPR-S between groups MM[-0.02(-0.60;0.30)]and E[-0.44(-0.89;-0.04)](P<0.001),and LM[-0.28(-0.71;0.12)]and E(P<0.05).There were also significant differences of RPR-T between groups MM[0.37(0.21;0.78)]and LH[0.14(-0.52;0.50)](P<0.05),LM[0.41(0.06;0.84)]and LH(P<0.05),and LM and E[0.29(-0.10;0.68),P<0.05].A Spearman’s correlation analysis showed a negative correlation between RPR and SE in the 15°-30°(P=0.005),30°-45°(P<0.05)annular(P=0.002),superior(P<0.001),and temporal(P=0.001)***:Without pupil dilation,values for RPR 15-30,30-45,RPR-S,and T shows significant differences between myopic eyes and emmetropia,and the differences are negatively correlated with SE.

关键词： relative peripheral refraction myopia school children multispectral refraction topography

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Efficacy of acupuncture in refractory irritable bowel syndrome patients:a randomized controlled trial

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Frontiers of Medicine 2024年第4期18卷 678-689页

作者： Jun Zhao hui Zheng Xin Wang Xuefei Wang Yunzhou Shi Chaorong Xie Qingfeng Tao Da Li Jingwen Sun Junjian Tian Junxia Gao huimin Liu Suhua Shi Jinxia Ni Rongdan Xue hui hu Min Chen Shuguang Yu Zhigang Li School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing100029China The Third Hospital/Acupuncture and Tuina School Chengdu University of Traditional Chinese MedicineChengdu610000China Beijing Hospital of Traditional Chinese Medicine Capital Medical UniversityBeijing100010China Department of Acupuncture and Moxibustion Dongzhimen Hospital Affiliated to Beijing University of Chinese MedicineBeijing100700China Department of Rehabilitation The Third Affiliated Hospital of Beijing University of Chinese MedicineBeijing100029China Department of Acupuncture and Moxibustion Dongfang Hospital Affiliated with Beijing University of Chinese MedicineBeijing100078China Anorectal Disease Department Hospital of Chengdu University of Traditional Chinese MedicineChengdu610075China Department of Integrated Traditional and Western Medicine West China HospitalSichuan UniversityChengdu610044China

Previous studies have confirmed that acupuncture for irritable bowel syndrome(IBS)provided an additional benefit over usual care ***,we performed a multicenter,randomized,sham-controlled trial to assess the efficacy and safety of acupuncture versus sham acupuncture for refractory IBS in patients in the context of conventional *** in the acupuncture and sham acupuncture groups received real or sham acupuncture treatment in 3 sessions per week for a total of 12 *** primary outcome was a change in the IBS–Symptom Severity Scale(IBS-SSS)score from baseline to week 4.A total of 521 participants were screened,and 170 patients(85 patients per group)were enrolled and included in the intention-to-treat *** characteristics were comparable across the two *** baseline to 4 weeks,the IBS-SSS total score decreased by 140.0(95%CI:126.0 to 153.9)in the acupuncture group and 64.4(95%CI:50.4 to 78.3)in the sham acupuncture *** between-group difference was 75.6(95%CI:55.8 to 95.4).Acupuncture efficacy was maintained during the 4-week follow-up *** were no serious adverse *** conclusion,acupuncture provided benefits when combined with treatment as usual,providing more options for the treatment of refractory IBS.

关键词： acupuncture functional gastrointestinal disorders irritable bowel syndrome clinical trial

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Synthesis of highly stable Ni nanoparticles via electrostatic self-assembly for enhanced hydrogen storage of MgH2

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Rare Metals 2024年第9期43卷 4356-4366页

作者： Qin-Ke Tang Jiang-Chuan Liu Rui Shi Yun-Feng Zhu Ji-Guang Zhang Ya-Na Liu Jun Wang Yao Zhang Xiao-hui hu Zhi-Bin Liu Li-Quan Li College of Materials Science and Engineering Jiangsu Collaborative Innovation Centre for Advanced Inorganic Function CompositesNanjing Tech University School of Materials Science and Engineering Southeast University

Magnesium-based hydrides have been widely recognized as an appropriate choice for solid-state hydrogen ***,its undesirable thermodynamics and sluggish hydrogenation/dehydrogenation kinetics are major bottlenecks for its ***,a highly stable and highly dispersed Ni-based catalyst （Ni/Al2O3/GN） was fabricated to promote the hydrogen storage performance of MgH2via the electrostatic effect of NiAl-LDH/GN precursor with a co-calcination reduction ***2-5wt % Ni/Al2O3/GN exhibits excellent hydrogen storage performance,releasing about 5.7 wt % hydrogen in 3500 s at 250℃,and can reach a saturation hydrogen absorption of about 6.15 wt% in 3000 s at 100℃.Furthermore,it also shows low dehydrogenation apparent activation energy of 89.1 and 118.2 kJ·***,the catalyst ensures the stability of both the physical phase and structure during ball milling and cycling *** role of each phase in Ni/Al2O3/GN on the hydrogen storage performance of MgH2was also discussed through experiments and theoretical calculation,and the synergistic catalytic mechanism of Ni/Al2O3/GN was clearly *** work provides a unique perspective for the preparation of highly stable and highly dispersible catalysts.

关键词： Catalytic mechanism Hydrogen storage performance Magnesium hydride Ni/Al2O3/GN

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基于LWN-Net的印刷电路板缺陷检测算法

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计算机集成制造系统 2024年第2期30卷 496-507页

作者：文斌胡晖杨超三峡大学电气与新能源学院湖北宜昌443002

针对现阶段印刷电路板缺陷检测任务中网络精度低、速度慢、模型参数量大的问题,提出基于改进YOLOv3的轻量级权重新型网络(LWN-Net),并提出轻量级特征增强网络作为模型的特征提取网络,解决YOLOv3中主干网络Darknet53参数量过多的问题。... 详细信息

针对现阶段印刷电路板缺陷检测任务中网络精度低、速度慢、模型参数量大的问题,提出基于改进YOLOv3的轻量级权重新型网络(LWN-Net),并提出轻量级特征增强网络作为模型的特征提取网络,解决YOLOv3中主干网络Darknet53参数量过多的问题。考虑到特征提取过程中语义信息和位置信息不平衡会导致检测精度降低,构建权重聚合分配机制消除不平衡,以提高模型特征提取能力。提出新型特征金字塔网络,增强网络对细节信息的提取能力并降低信息冗余度。采用回归损失函数SIoU加快模型的收敛速度并提高检测精度。结果表明,相比YOLOv3,LWN-Net网络的模型规模压缩了87.5%,而检测速度提升了8.32帧·s^(-1),预测精度和召回率分别提升了0.88%和1.6%。该网络的提出为印刷电路板的缺陷检测问题提供了一种更高效的方法。

关键词： PCB缺陷检测 YOLOv3 轻量级 SIoU损失函数

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新媒体视域下非遗数字化研究——以隆回花瑶挑花微信小程序为例

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艺术与设计（理论版） 2024年第2期 51-53页

作者：胡慧陶欢焦柳湖南科技大学建筑与艺术设计学院湖南湘潭411201

互联网时代的更迭为非物质文化遗产的传承与传播带来了新的挑战和机遇,为当代非遗数字化保护提供了更为科学便捷的方式。隆回花瑶挑花独具魅力,但面临着传承人失传、传播方式单一和信息渠道落后等问题,文章结合数字化时代的特点,提出隆... 详细信息

互联网时代的更迭为非物质文化遗产的传承与传播带来了新的挑战和机遇,为当代非遗数字化保护提供了更为科学便捷的方式。隆回花瑶挑花独具魅力,但面临着传承人失传、传播方式单一和信息渠道落后等问题,文章结合数字化时代的特点,提出隆回花瑶挑花微信小程序的建设构想,将非遗文化隆回花瑶挑花与微信小程序设计结合起来,从而实现隆回花瑶挑花文化的数字化保护与传承。

关键词：非物质文化遗产新媒体隆回花瑶挑花微信小程序设计数字化

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