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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 9-15页

作者： Jingyuan Li Cui-Qun Chen Chaoxin Huang Yifeng Han Mengwu Huo Xing Huang Peiyue Ma Zhengyang Qiu Junfeng Chen Xunwu Hu Lan Chen Tao Xie Bing Shen hualei sun Dao-Xin Yao Meng Wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China Center for Materials of the Universe School of Molecular SciencesArizona State UniversityTempe 85287USA School of Sciences Sun Yat-sen UniversityShenzhen 518107China

Atomic structure and electronic band structure are fundamental properties for understanding the mechanism of superconductivity. Motivated by the discovery of pressure-induced high-temperature superconductivity at 80 K in the bilayer Ruddlesden-Popper nickelate La_(3)Ni_(2)O_(7), the atomic structure and electronic band structure of the trilayer nickelate La_(4)Ni_(3)O_(10) under pressure up to 44.3 GPa are investigated. A structural transition from the monoclinic P2_(1)/a space group to the tetragonal I4/mmm around 12.6-13.4 GPa is identified, accompanied by a drop of resistance below 7 K. Density functional theory calculations suggest that the bonding state of Ni 3d_(z^(2)) orbital rises and crosses the Fermi level at high pressures, which may give rise to possible superconductivity observed in resistance under pressure in La_(4)Ni_(3)O_(10). The trilayer nickelate La_(4)Ni_(3)O_(10) shows some similarities with the bilayer La_(3)Ni_(2)O_(7) and has unique properties, providing a new platform to investigate the underlying mechanism of superconductivity in nickelates.

关键词： La_(4)Ni_(3)O_(10) high pressure synchrotron X-ray diffraction structural transition DFT calculations

Magnetism variation of the compressed antiferromagnetic topological insulator EuSn_(2)As_(2)

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Science China(Physics,Mechanics & Astronomy) 2021年第11期64卷 133-140页

作者： hualei sun Cuiqun Chen Yusheng Hou Weiliang Wang Yu Gong Mengwu Huo Lisi Li Jia Yu Wanping Cai Naitian Liu Ruqian Wu Dao-Xin Yao Meng Wang Center for Neutron Science and Technology School of PhysicsSun Yat-Sen UniversityGuangzhou 510275China School of Physics Guangdong Province Key Laboratory of Display Material and TechnologySun Yat-Sen UniversityGuangzhou 510275China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Physics and Astronomy University of CaliforniaIrvineIrvine 92697-4575USA

We report a comprehensive high-pressure study,up to 21.1 GPa,on the antiferromagnetic topological insulator EuSn_(2)As_(2) achieved through synchrotron X-ray diffraction,Raman scattering,electrical resistance,magnetic resistance,and Hall transport measurements in combination with first-principles *** Néel temperatures determined from resistance are increased from(24±1)to(77±8)K under pressure,which is a result of enhanced magnetic exchange couplings between Eu^(2+) ions yielded by our first-principles *** negative magnetoresistance of EuSn_(2)As_(2) persists to higher temperatures ***,the enhancement of the observed Néel temperatures deviates from the calculations above 10.0 *** addition,the magnitude of the magnetoresistance,Hall coefficients,and charge carrier densities show abrupt changes between 6.9 and 10.0 *** abrupt changes likely originate from a pressure-induced valence change of Eu ions from a divalent state to a divalent and trivalent mixed state or are related to the structural transition revealed by Raman scattering *** results provide insight into magnetism variation in EuSn_(2)As_(2) and similar antiferromagnetic topological insulators under pressure.

关键词： antiferromagnetism topological insulator high pressure

Evidence for charge and spin density waves in single crystals of La_(3)Ni_(2)O_(7) and La_(3)Ni_(2)O_(6)

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Science China(Physics,Mechanics & Astronomy) 2023年第1期66卷 164-170页

作者： Zengjia Liu hualei sun Mengwu Huo Xiaoyan Ma Yi Ji Enkui Yi Lisi Li Hui Liu Jia Yu Ziyou Zhang Zhiqiang Chen Feixiang Liang Hongliang Dong Hanjie Guo Dingyong Zhong Bing Shen Shiliang Li Meng Wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Center for High Pressure Science and Technology Advanced Research Shanghai 201203China Songshan Lake Materials Laboratory Dongguan 523808China

Charge and spin orders are intimately related to superconductivity in copper oxide *** of the competing orders in various nickel oxide compounds is crucial,given the fact that superconductivity has been discovered in Nd_(0.8)Sr_(0.2)NiO_(2)***,we report structural,electronic transport,magnetic,and thermodynamic characterizations of single crystals of La_(3)Ni_(2)O_(7)and La_(3)Ni_(2)O_(6).La_(3)Ni_(2)O_(7)is metallic with mixed Ni^(2+)and Ni^(3+)valent *** measurements yield two transition-like kinks at~110 and 153 *** kink at 153 K is further revealed from magnetization and specific heat measurements,indicative of the formation of charge and spin density ***_(3)Ni_(2)O_(6)single crystals obtained from the topochemical reduction of La_(3)Ni_(2)O_(7)are insulating and show an anomaly at~176 K on magnetic *** transition-like behaviors of La_(3)Ni_(2)O_(7)and La_(3)Ni_(2)O_(6)are analogous to those observed in La_(4)Ni_(3)O_(10) and La_(4)Ni_(3)O_(8),suggesting that charge and spin density waves are a common feature in the ternary La-Ni-O system with mixed-valent states of nickel.

关键词： charge-density-wave systems spin-density waves mixed-valence solids superlattices crystal growth

Synthesis and properties of La_(1-x)Sr_(x)NiO_(3) and La_(1-x)Sr_(x)NiO_(2)

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Chinese Physics B 2022年第10期31卷 529-533页

作者： Mengwu Huo Zengjia Liu hualei sun Lisi Li Hui Lui Chaoxin Huang Feixiang Liang Bing Shen Meng Wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-Sen UniversityGuangzhou 510275China

Superconductivity has been realized in films of La_(1-x)Sr_(x)NiO_(2). Here we report synthesis and characterization of polycrystalline samples of La_(1-x)Sr_(x)NiO_(3) and La_(1-x) Sr_(x)NiO_(2)(0 ≤ x ≤ 0.2). Magnetization and resistivity measurements reveal that La_(1-x)Sr_(x)NiO_(3) are paramagnetic metal and La_(1-x)Sr_(x)NiO_(2) exhibit an insulating behavior. Superconductivity is not detected in bulk samples of La_(1-x)Sr_(x)NiO_(2). The absence of superconductivity in bulk La_(1-x)Sr_(x)NiO_(2) may be due to the generation of hydroxide during reduction, a small amount of nickel impurity, or incomplete reduction of apical *** effect of interface in films of La_(1-x)Sr_(x)NiO_(2) may also play a role for superconductivity.

关键词： nickel oxide superconductivity

水含量对超临界CO_(2)输送管道腐蚀的影响

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中国腐蚀与防护学报 2024年第3期44卷 576-584页

作者：胡丽华衣华磊杨维健孙冲孙建波中海油研究总院有限责任公司北京100028 中国石油大学(华东)材料科学与工程学院青岛266580

通过模拟实验和表面分析技术等方法,对比研究有无杂质的超临界CO_(2)输送环境中水含量对X65管线钢腐蚀行为的影响,并探讨不同水含量环境中杂质对X65钢腐蚀的影响机理。结果表明:在超临界CO_(2)-H_(2)O环境中,即使水含量达到饱和溶解度0.... 详细信息

通过模拟实验和表面分析技术等方法,对比研究有无杂质的超临界CO_(2)输送环境中水含量对X65管线钢腐蚀行为的影响,并探讨不同水含量环境中杂质对X65钢腐蚀的影响机理。结果表明:在超临界CO_(2)-H_(2)O环境中,即使水含量达到饱和溶解度0.4114%,X65钢也仅发生轻微腐蚀,腐蚀速率为0.0013 mm/a。在O_(2)、H_(2)S、SO_(2)和NO_(2)杂质共存的超临界CO_(2)-H_(2)O环境中,水含量由0.002%增加至0.4114%,X65钢腐蚀速率由0.0181 mm/a增加至0.2901 mm/a。杂质与杂质间交互作用显著促进腐蚀性液相形成,进而加剧X65钢的腐蚀。在低含水量环境中,X65钢腐蚀过程由杂质间反应产物控制;而在高含水量环境中,杂质和杂质间反应产物共同控制X65钢的腐蚀过程。

关键词： X65 管线钢超临界CO_(2) 水含量杂质腐蚀

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感染管理科参与发热门诊改造的实践

中国医院建筑与装备 2022年第10期23卷 16-19页

作者：孙玲赵全国孙化蕾滕州市中心人民医院滕州277599 山东泰山地勘集团有限公司济南250000

以某三级综合医院发热门诊改造为例,阐述了在改造过程中感染管理科提早介入、积极学习相关文件、提高图纸会审能力、全程参与改造项目的实践,为感染控制的效果提供了保障。

关键词：医院建筑改造发热门诊感染控制

紫檀芪对2型糖尿病大鼠学习记忆能力及海马氧化应激水平的影响

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郑州大学学报（医学版） 2019年第1期54卷 51-54页

作者：刘欣欣孙华磊葛惠娜王腾李文杰郑州大学公共卫生学院营养与食品卫生学教研室郑州450001

目的:探讨紫檀芪对2型糖尿病大鼠学习记忆能力及海马组织氧化应激水平的影响。方法:100只4周龄雄性SD大鼠适应性喂养1周后,选取10只作为正常对照组,其余大鼠给予高脂高糖饲料喂养。4周后夜间禁食12 h,按40 mg/kg剂量一次性空腹注射链脲... 详细信息

目的:探讨紫檀芪对2型糖尿病大鼠学习记忆能力及海马组织氧化应激水平的影响。方法:100只4周龄雄性SD大鼠适应性喂养1周后,选取10只作为正常对照组,其余大鼠给予高脂高糖饲料喂养。4周后夜间禁食12 h,按40 mg/kg剂量一次性空腹注射链脲佐菌素溶液,制备2型糖尿病大鼠模型。选取造模成功的大鼠40只分为2型糖尿病组、紫檀芪低剂量组、紫檀芪中剂量组、紫檀芪高剂量组,每组10只。紫檀芪干预7周后,采用全自动生化分析仪检测血糖和血清胰岛素,用Morris水迷宫测定大鼠学习记忆能力,用氧化酶试剂盒检测海马组织中SOD活性和MDA水平。结果:与正常对照组相比,2型糖尿病组大鼠血糖、血清胰岛素水平升高(P<0.05);与2型糖尿病组大鼠相比,紫檀芪低、中剂量组血糖降低,紫檀芪低、中、高剂量组血清胰岛素水平降低(P<0.05)。同时,与正常对照组相比,2型糖尿病组大鼠逃避潜伏期延长,穿越平台次数减少,海马组织SOD活性降低,MDA水平增加(P<0.05);与2型糖尿病组大鼠相比,紫檀芪低、中、高剂量组逃避潜伏期缩短,穿越平台次数增加,海马组织SOD活性升高,MDA水平降低(P<0.05)。结论:紫檀芪可以改善2型糖尿病大鼠学习记忆能力,提高海马组织SOD活性,对2型糖尿病大鼠认知障碍具有一定的改善作用。

关键词：紫檀芪 2型糖尿病学习记忆能力大鼠

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紫檀芪对3T3-L1前脂肪细胞分化的影响

郑州大学学报（医学版） 2020年第1期55卷 45-48页

作者：王腾孙华磊葛惠娜刘欣欣李星李文杰郑州大学公共卫生学院营养与食品卫生学教研室

目的:观察紫檀芪(PTE)对3T3-L1前脂肪细胞分化的影响并探讨其可能的机制。方法:使用“经典鸡尾酒”法诱导3T3-L1前脂肪细胞进行分化,并在诱导分化过程中的前48 h进行PTE干预(15、30、60μmol/L),细胞诱导分化完成后,通过油红O染色检测... 详细信息

目的:观察紫檀芪(PTE)对3T3-L1前脂肪细胞分化的影响并探讨其可能的机制。方法:使用“经典鸡尾酒”法诱导3T3-L1前脂肪细胞进行分化,并在诱导分化过程中的前48 h进行PTE干预(15、30、60μmol/L),细胞诱导分化完成后,通过油红O染色检测细胞分化程度,采用葡萄糖氧化酶-过氧化物酶法检测细胞糖消耗量,游离脂肪酸测定试剂盒测定培养基中游离脂肪酸含量,Western blot测定细胞中PPARγ和C/EBPα蛋白的表达。结果:与对照组相比,PTE低、中、高剂量组细胞分化程度明显降低,脂质聚集减少(P<0.05);与对照组相比,各PTE剂量组细胞糖消耗量提升,游离脂肪酸生成减少,PPARγ和C/EBPα蛋白表达水平降低,并且PTE高剂量组作用最强(P<0.05)。结论:PTE能够抑制3T3-L1前脂肪细胞分化,改善脂肪细胞的糖脂代谢,其机制可能与抑制PPARγ、C/EBPα蛋白表达有关。

关键词：紫檀芪前脂肪细胞细胞分化

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紫檀芪对2型糖尿病大鼠肝损伤的作用

郑州大学学报（医学版） 2020年第3期55卷 360-364页

作者：张玉晶孙华磊刘欣欣王腾李星李文杰郑州大学公共卫生学院营养与食品卫生学教研室郑州450001

目的:探讨紫檀芪(PTE)对2型糖尿病(T2DM)大鼠肝损伤的作用。方法:50只大鼠分为正常对照组,模型组及低、中、高剂量PTE组,每组10只。除正常对照组外,其他4组采用高脂高糖饮食和链脲佐菌素诱导T2DM模型,低、中、高剂量PTE组分别给予20、40... 详细信息

目的:探讨紫檀芪(PTE)对2型糖尿病(T2DM)大鼠肝损伤的作用。方法:50只大鼠分为正常对照组,模型组及低、中、高剂量PTE组,每组10只。除正常对照组外,其他4组采用高脂高糖饮食和链脲佐菌素诱导T2DM模型,低、中、高剂量PTE组分别给予20、40、80 mg/kg PTE处理,1次/d。12周后,采用HE染色观察大鼠肝组织形态学变化,采用比色法测定血清ALT、AST水平,ELISA法测定血清白细胞介素6(IL-6)、IL-1β和肿瘤坏死因子-α(TNF-α)水平,Western blot法检测肝组织NF-κB、IL-6蛋白的表达水平。结果:与正常对照组相比,模型组肝小叶肝索结构紊乱,肝细胞肿胀、体积增大,细胞质疏松,局部炎性细胞浸润、出血;血清ALT、AST、IL-6、IL-1β、TNF-α水平以及肝组织NF-κB和IL-6蛋白表达水平升高(P<0.05)。与模型组相比,低、中、高剂量PTE组肝组织结构均有所改善,血清ALT、AST、IL-6水平以及肝组织NF-κB、IL-6蛋白表达水平均降低;高剂量PTE组血清IL-1β水平降低,低、高剂量PTE组血清TNF-α水平降低(P<0.05)。结论:PTE可减轻T2DM造成的肝损伤,其机制可能与抑制NF-κB/IL-6通路及炎症反应有关。

关键词：紫檀芪 2型糖尿病大鼠肝脏炎症

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紫檀芪对2型糖尿病大鼠肾损伤的改善作用

郑州大学学报（医学版） 2022年第1期57卷 18-22页

作者：丁润蓉孙华磊刘亚萍张玉晶李星李文杰郑州大学公共卫生学院营养与食品卫生学教研室郑州450001

目的:探讨紫檀芪(PTE)对2型糖尿病(T2DM)大鼠肾损伤的改善作用及其机制。方法:采用高脂高糖饮食联合链脲佐菌素(STE,40 mg/kg)诱导大鼠T2DM型,成模后,随机分为T2DM对照组,低、中、高剂量PTE组(20、40和80 mg/kg)和罗格列酮组(5 mg/kg),1... 详细信息

目的:探讨紫檀芪(PTE)对2型糖尿病(T2DM)大鼠肾损伤的改善作用及其机制。方法:采用高脂高糖饮食联合链脲佐菌素(STE,40 mg/kg)诱导大鼠T2DM型,成模后,随机分为T2DM对照组,低、中、高剂量PTE组(20、40和80 mg/kg)和罗格列酮组(5 mg/kg),1次/d,干预6周,每组10只。以普通饲料喂养的大鼠作正常对照(n=10)。采用全自动生化分析仪测定干预前后空腹血糖、甘油三酯(TG)、总胆固醇(TC)、尿素氮(BUN)水平;干预6周后HE染色观察大鼠肾脏组织形态学变化,Western blot法检测肾组织NF-κB、TGF-β1和α-SMA蛋白表达水平。结果:与正常对照组相比,T2DM对照组大鼠肾小球基底膜变厚,伴有炎性细胞浸润,血糖、TG、TC、BUN水平以及肾组织中NF-κB、TGF-β1和α-SMA蛋白表达水平升高(P<0.05)。与T2DM对照组相比,PTE组肾组织炎性细胞浸润减少,基底膜变薄,血糖、TG、TC水平降低(P<0.05);肾组织NF-κB、TGF-β1、α-SMA蛋白表达水平降低(P<0.05)。结论:PTE可以改善STZ诱导的糖尿病大鼠肾脏损伤,其机制可能与调节NF-κB/TGF-β1信号通路进而抑制炎症和纤维化反应有关。

关键词：紫檀芪 2型糖尿病肾脏炎症纤维化大鼠