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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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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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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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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： Zhao, Jun Zheng, hui Wang, Xin Wang, Xuefei Shi, Yunzhou Xie, Chaorong Tao, Qingfeng Li, Da Sun, Jingwen Tian, Junjian Gao, Junxia Liu, huimin Shi, Suhua Ni, Jinxia Xue, Rongdan hu, hui Chen, Min Yu, Shuguang Li, Zhigang Beijing Univ Chinese Med Sch Acupuncture Moxibust & Tuina Beijing 100029 Peoples R China Sichuan Univ West China Hosp Dept Integrated Tradit & Western Med Chengdu Peoples R China Chengdu Univ Tradit Chinese Med Hosp 3 Acupuncture & Tuina Sch Chengdu 610000 Peoples R China Capital Med Univ Beijing Hosp Tradit Chinese Med Beijing 100010 Peoples R China Beijing Univ Chinese Med Dept Acupuncture & Moxibust Dongzhimen Hosp Beijing 100700 Peoples R China Beijing Univ Chinese Med Affiliated Hosp 3 Dept Rehabil Beijing 100029 Peoples R China Beijing Univ Chinese Med Dongfang Hosp Dept Acupuncture & Moxibust Beijing 100078 Peoples R China Hosp Chengdu Univ Tradit Chinese Med Anorectal Dis Dept Chengdu 610075 Peoples R China

Previous studies have confirmed that acupuncture for irritable bowel syndrome (IBS) provided an additional benefit over usual care alone. Therefore, 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 treatments. Patients in the acupuncture and sham acupuncture groups received real or sham acupuncture treatment in 3 sessions per week for a total of 12 sessions. The 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 analysis. Baseline characteristics were comparable across the two groups. From 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 group. The between-group difference was 75.6 (95% CI: 55.8 to 95.4). Acupuncture efficacy was maintained during the 4-week follow-up period. There were no serious adverse events. In 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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Fiber optic high temperature sensor with weak strain sensitivity based on Mach-Zehnder interferometric structure

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Optoelectronics Letters 2024年

作者： LIU Ming MA Chengju ZHANG Yixin LIU Qianzhen hu hui WU Jirui School of Science， Xi'an Shiyou University

We proposed a fiber optic high temperature sensor based on the Mach-Zehnder (M-Z) interference structure， which is composed of two lengths of multi-mode fiber (MMF)， a length of few-mode fiber (FMF) and two sections of single-mode fiber (SMF). Firstly， the two sections of MMF were spliced with two sections of SMF. Then， the MMFs were fused to two ends of FMF to form a symmetrically structured fiber-optic M-Z interferometric structure. In this structure， the multimode fiber served as the optical mode field coupling element， and the cladding and core of the FMF are the interference arm and the reference arm of the M-Z interference structure， respectively. We investigated the sensor’s response characteristics of the temperature and strain. The experimental results indicate that the sensor is sensitive to temperature variation， and the temperature response sensitivity is up to 61.4 pm/℃ in the range of 40 ～ 250 ℃， while the sensor has weak strain sensitivity， its strain sensitivity is only -0.72 pm/με in the strain range of 0 με to 1400 με，. Moreover， the sensor has good stability and repeatability. In brief， the fiber optic high temperature sensor proposed by us has good properties， such as high sensitivity， compact structure， good stability and repeatability， it can be used for monitoring the temperature of submerged oil electric pump units under oil wells.

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深海载人潜水器的水下稳性分析研究

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船舶力学 2024年第5期28卷 716-724页

作者：胡中惠刘帅曲文新叶聪胡震中国船舶科学研究中心江苏无锡214082 深海载人装备国家重点实验室江苏无锡214082 深海技术科学太湖实验室江苏无锡214082

水下稳性是深海载人潜水器重要的总体性能之一,通过稳心高(GB)衡量潜水器的稳性,其指标大小与潜水器的操纵和安全息息相关。潜水器在运动过程中,海洋参数随深度变化以及潜水器自身压载变化引起潜水器稳心高发生变化。本文以稳心高基本... 详细信息

水下稳性是深海载人潜水器重要的总体性能之一,通过稳心高(GB)衡量潜水器的稳性,其指标大小与潜水器的操纵和安全息息相关。潜水器在运动过程中,海洋参数随深度变化以及潜水器自身压载变化引起潜水器稳心高发生变化。本文以稳心高基本公式为基础,结合潜水器耐压结构、浮力材料和液压油的浮力损失计算方法,建立深海载人潜水器水下稳心高数学模型,提出一种深海载人潜水器水下稳性分析方法。以“深海勇士”号载人潜水器为研究对象,对深海载人潜水器的水下稳性进行计算分析,得出深海载人潜水器水下稳心高的变化规律,可为深海载人潜水器的设计提供参考。

关键词：载人潜水器水下稳性稳心高

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基于PLUS-InVEST模型的哈尔滨市土地利用及生境质量预测

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环境科学 2024年第8期45卷 4709-4721页

作者：张廷胡玉柱胡海辉雷婷婷东北农业大学园艺园林学院哈尔滨150030 阿坝师范学院物理与电子电气工程学院阿坝623002

分析城市土地利用与生境质量时空演变,能够揭示土地利用和生境质量的关联性,有助于城市土地政策合理决策和生态环境高质量发展.研究基于土地利用转移矩阵和IM模型分析哈尔滨市2000~2020年土地利用的变化,并结合PLUS模型进行各用地类型... 详细信息

分析城市土地利用与生境质量时空演变,能够揭示土地利用和生境质量的关联性,有助于城市土地政策合理决策和生态环境高质量发展.研究基于土地利用转移矩阵和IM模型分析哈尔滨市2000~2020年土地利用的变化,并结合PLUS模型进行各用地类型扩张因子的驱动探究以及2030年自然发展情景、生态保护情景、耕地保护情景和城镇发展情景下的土地利用预测,最后利用InVEST模型完成生境质量分析.结果表明:①哈尔滨市土地利用类型以耕地、林地和草地为主,2000~2020年期间,草地、耕地、林地和人造地表转入面积较多,土地利用强度变化倾向性特征明显;水体、裸地和湿地类型的转入较少,多呈现抑制性特征.②高程是影响草地、耕地、林地、裸地、湿地和水体扩张的主要因子;影响人造地表扩张的主要因子是社会经济因素.③模拟哈尔滨市2030年4种情景下各土地利用类型面积,其中林地面积均增加,草地面积均减少,湿地、水体和裸地面积变化均不显著;除生态保护情景外,人造地表面积均增加,耕地面积均减少.④2000~2020年间,哈尔滨市生境质量整体提高.⑤2030年哈尔滨市4种情景下生境质量空间格局演变规律整体保持一致,生境质量均呈现变好趋势,其中生态保护情景下低、中等生境质量面积减少,而较高、高生境质量面积有所增加,生境质量提升相对明显.研究结果可为哈尔滨市生态文明发展以及城市规划建设提供一定的科学依据及思路.

关键词：土地利用变化生境质量 PLUS模型 InVEST模型哈尔滨市

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粮食直接补贴的全要素生产率效应--以水稻为例

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中南民族大学学报（人文社会科学版） 2024年第3期44卷 140-147,187页

作者：闵锐胡卓辉中南民族大学经济学院/湖北全面小康研究院湖北武汉430074 中南林业科技大学商学院湖南长沙410004

利用2006-2020年全国23个省市区的面板数据,采用面板分位数模型,研究粮食直接补贴的全要素生产率效应及其时空差异。结果显示:我国水稻全要素生产率整体呈增长态势,且技术进步为增长主要来源;粮食直接补贴对各分位点水稻全要素生产率的... 详细信息

利用2006-2020年全国23个省市区的面板数据,采用面板分位数模型,研究粮食直接补贴的全要素生产率效应及其时空差异。结果显示:我国水稻全要素生产率整体呈增长态势,且技术进步为增长主要来源;粮食直接补贴对各分位点水稻全要素生产率的影响系数均为负,但低水平的负面影响更显著;观察期内,粮食直接补贴对水稻全要素生产率的影响系数在“十三五”时期由负转为正;粮食直接补贴对不同经济发展水平地区的影响存在差异,东北地区具有正面影响。据此,建议重视水稻生产技术进步,并持续改革和优化粮食直接补贴政策,未来相关政策增量资金可向东北地区倾斜,促进我国粮食生产高质量发展与粮食安全。

关键词：粮食直接补贴全要素生产率政策效应

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超高压爆破片设计爆破压力的半经验计算公式

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压力容器 2024年第3期41卷 41-48页

作者：杨超惠虎骆辉薄柯中国特种设备检测研究院北京100029 华东理工大学机械与动力工程学院上海200237 国家市场监管重点实验室(氢能储运装备安全) 浙江嘉兴314050 嘉兴市长三角氢安全研究中心浙江嘉兴314000

针对超高压正拱型爆破片提出设计爆破压力的半经验计算公式,开展超高压爆破片预拱变形后非均匀减薄壁厚的测量试验,借助试验数据对爆破片变形后非均匀减薄壁厚的理论计算公式进行修正,同时,为进一步简化半经验公式及过程,选取不同材料... 详细信息

针对超高压正拱型爆破片提出设计爆破压力的半经验计算公式,开展超高压爆破片预拱变形后非均匀减薄壁厚的测量试验,借助试验数据对爆破片变形后非均匀减薄壁厚的理论计算公式进行修正,同时,为进一步简化半经验公式及过程,选取不同材料、爆破压力和挠曲高度的试验数据,建立爆破片挠曲高度和材料应变硬化指数之间的关联关系,对设计爆破压力半经验公式化繁为简,利用试验方法,对爆破片的爆破压力进行试验验证,试验结果与理论计算结果吻合较好,其误差分别为3.72%和6.59%,对实际工程应用具有指导意义。

关键词：超高压爆破片设计爆破压力周向应变经向应变径向应变

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