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Ultrafast quasiparticle dynamics in spin-density-wave LaOFeAs single crystal

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Science China(Physics,Mechanics & Astronomy) 2013年第12期56卷 2395-2398页

作者： chen rongyan DONG Tao WANG HaiPeng WANG NanLin Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences

Ultrafast quasiparticle dynamics of single crystalline LaOFeAs were investigated by pump-probe *** compound experiences structural and spin-density-wave(SDW)phase transitions at 150 K(TS1)and 130 K(TS2),*** relaxation time of quasiparticles was somewhat temperature independent at high temperature but exhibited a sharp upturn at TS1and reached the maximum at approximately *** remarkable slowing down of quasiparticle relaxation time is caused by the formation of energy *** employing the Rothwarf-Taylor model analysis,we found that there should be already energy gaps opening just below the structural *** magnitude of SDW gap was identified to be 72 meV.

关键词： ultrafast LaOFeAs spin-density-wave (SDW)

Optical study on topological superconductor candidate Sr-doped Bi_(2)Se_(3)

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Chinese Physics B 2022年第11期31卷 536-541页

作者： Jialun Liu chennan Wang Tong Lin Liye Cao Lei Wang Jiaji Li Zhen Tao Nan Shen Rina Wu Aifang Fang Nanlin Wang rongyan chen Center for Advanced Quantum Studies and Department of Physics Beijing Normal UniversityBeijing 100875China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

Utilizing infrared spectroscopy,we study the charge dynamics of the topological superconductor candidate Sr_(x)Bi_(2)Se_(3).The frequency-dependent reflectivity R(ω)demonstrates metallic feature and the scattering rate of the free carriers decreases with temperature *** plasma edge shows a slight blue shift upon cooling,similar to the behavior of Cu_(x)Bi_(2)Se_(3).As the carrier concentration n obtained by Hall resistivity increases slightly with the decreasing temperature,the effective mass is proved to increase as well,which is in contrast with that of Cu_(x)Bi_(2)Se_(3).We also perform the ultrafast pump-probe study on the Sr_(0.2)Bi_(2)Se_(3)*** its parent compound Bi_(2)Se_(3),three distinct relaxation processes are found to contribute to the transient ***,the deduced relaxation times are quite *** addition,the electron-optical-phonon coupling constant is identified to beλ=0.88.

关键词： topological superconductor infrared spectroscopy ultrafast spectroscopy

Mott gap engineering in Sr2IrO4/SrTiO3 superlattices

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Science China Materials 2020年第9期63卷 1855-1860页

作者： Xin Liu Yuben Yang Qinghua Zhang Dayu Yan Jingdi Lu rongyan chen Youguo Shi Changmin Xiong Fa Wang Lin Gu Jinxing Zhang Department of Physics Beijing Normal UniversityBeijing 100875China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China International Center for Quantum Materials Peking UniversityBeijing 100871China

In recent years,iridium oxides have attracted intensive research interests both in experiments and theories due to their comparable energy scales of the Coulomb repulsion and strong spin-orbit coupling(SOC)[1,2],where a plenty of novel quantum states such as Weyl semimetal,topological insulator and quantum spin liquid have been studied[3–7].Among the iridates,the layered-perovskite Sr2IrO4(SIO)is a Jeff=1/2 Mott insulating antiferromagnet caused by the interplay of the SOC and electronic correlations[8,9].

关键词：自旋轨道耦合量子现象 SrTiO3 过渡金属氧化物强关联超晶格分子束外延原子尺度

Hidden metal-insulator transition in manganites synthesized via a controllable oxidation

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Science China Materials 2019年第4期62卷 577-585页

作者： Chuangye Song Iftikhar Ahmed Malik Menglei Li Qinghua Zhang Lichen Wang Jing Wang rongyan chen Renkui Zheng Shuai Dong Lin Gu Wenhui Duan Ce-Wen Nan Jinxing Zhang Department of physics Beijing Normal University Department of Physics Capital Normal University Institute of physics Chinese Academy of Sciences School of Materials Science and Engineering Tsinghua University Center for Advanced Quantum Studies Beijing Normal University State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences School of Physics Southeast University Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua University

Oxygen usually plays crucial roles in tuning the phase structures and functionalities of complex oxides such as high temperature superconductivity, colossal magnetoresistance, catalysis, etc. Effective and considerable control of the oxygen content in those functional oxides could be highly desired. Here, using perovskite manganite(La0.5Sr0.5)MnO3 as a paradigm, we develop a new pathway to synthesize the epitaxial thin films assisted by an in-situ chemical process, where the oxygen content can be precisely controlled by varying oxidative activity tuned by the atmospheric temperature(Tatm)during the growth. A hidden metal-insulator transition(MIT)emerges due to the phase competition, which is never shown in the phase diagram of this classic manganite. The oxygenmediated interaction between Mn ions together with the change of carrier density might be responsible for this emerging phase, which is compatible with the results of firstprinciple calculations. This work demonstrates that, apart from traditional cation doping, a precise modulation of anion(O2-, S2-, etc.) may provide a new strategy to control phase structures and functionalities of epitaxial compound thin films.

关键词： oxidative-activity oxygen-content manganites hidden metal-insulator transition

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加权组合模型在城市用水量预测中的应用

应用基础与工程科学学报 2010年第3期18卷 428-434页

作者：王圃陈荣艳孙晓楠魏旭升重庆大学三峡库区生态环境教育部重点实验室重庆400045 重庆大学数理学院重庆400045 遂宁市明星自来水公司四川遂宁629200

鉴于传统灰色模型在建模中存在固有偏差的问题,本文采用无偏灰色GM(1,1)预测模型.在无偏灰色预测模型表达式的基础上,又提出了非线性的预测模型,并将其用于城市的用水量预测上.考虑到单一预测模型在预测过程中存在的不足,用最优加权组... 详细信息

鉴于传统灰色模型在建模中存在固有偏差的问题,本文采用无偏灰色GM(1,1)预测模型.在无偏灰色预测模型表达式的基础上,又提出了非线性的预测模型,并将其用于城市的用水量预测上.考虑到单一预测模型在预测过程中存在的不足,用最优加权组合模型对无偏灰色GM(1,1)模型和非线性模型进行组合,并将加权组合模型首次用于遂宁市的城市用水量预测.预测结果表明,组合模型的预测精度优于单一的预测模型,预测结果与城市的实际用水量拟合较好,该方法可推广到其它类似城市的用水量预测中.

关键词：加权组合模型无偏灰色模型非线性模型二次规划

四川省东部山区某长距离超高扬程输水工程设计总结

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供水技术 2023年第6期17卷 39-43页

作者：陈荣艳中国华西工程设计建设有限公司四川成都610000

四川省东部山区某长距离超高扬程输水工程,既有超高压力流输水管道的特点,又有超高重力流输水管道的特点,且各供水点的地形高差较大,增加了水锤防护的设计难度。为确保供水安全可靠,本工程进行水锤模拟分析,并采取一系列水锤防护措施,... 详细信息

四川省东部山区某长距离超高扬程输水工程,既有超高压力流输水管道的特点,又有超高重力流输水管道的特点,且各供水点的地形高差较大,增加了水锤防护的设计难度。为确保供水安全可靠,本工程进行水锤模拟分析,并采取一系列水锤防护措施,针对本工程试运行中存在的问题进行分析总结,可为其他工程的建设提供借鉴参考。

关键词：长距离输水超高扬程水锤防护

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城镇水厂挖潜改造技术措施及实践

供水技术 2017年第3期11卷 44-47页

作者：陈荣艳中国华西工程设计建设有限公司四川成都610017

针对现有城镇水厂面临水污染形势严峻问题、水质标准提高而制水工艺落后的状况,从增加预处理和深度处理、改造常规处理工艺等方面,总结了水厂挖潜改造的技术措施,以期为其他水厂的挖潜改造提供参考。

关键词：预处理深度处理挖潜改造

SELDI-TOF-MS筛选微小病变型肾病综合征尿液生物标志物

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第三军医大学学报 2010年第17期32卷 1842-1846页

作者：林青郑健陈蓉艳艾斯福建中医学院附属人民医院检验科福州350004 福建中医学院附属人民医院儿科福州350004

目的探讨应用优化的表面增强激光解析电离-飞行时间-质谱(surface enhanced laser desorption/ionizationtime of flight-mass spectrometry,SELDI-TOF-MS)进行微小病变型肾病综合征(minimal-changed nephrotic syndrome,MCNS)大鼠尿液生物标志物筛选的意义。方法 SD大鼠30只随机分为正常对照组(n=10)、模型对照组(n=10)和强的松治疗组(n=10)。除正常对照组外,其余大鼠经尾静脉一次性注射阿霉素5.5mg/kg复制MCNS模型,造模10d后分别予以强的松和蒸馏水灌胃治疗。21d后收集大鼠尿液,经弱阳离子交换芯片CM10捕获蛋白质,应用SELDI-TOF-MS获取3组大鼠的尿液蛋白质指纹图谱,采用Biomarker wizard软件比对分析差异蛋白。结果优化实验条件后获得较理想的尿液蛋白质指纹图谱,质控峰强度的平均CV值为18.0%(7.50%～35.89%)。在模型对照组与正常对照组之间检测到不同质荷比处有33个具统计学意义的差异蛋白峰(P<0.05),其中21个蛋白表达上调,12个蛋白表达下调。在正常对照组、模型对照组与强的松治疗组之间有6个蛋白质表达存在差异(P<0.05),这些差异蛋白峰在模型对照组中高表达,而在强的松治疗组中蛋白表达下调,峰强度接近正常对照组。结论通过优化实验条件并实行质量控制,SELDI-TOF-MS可为MCNS大鼠尿液生物标志物的筛选提供一个可行的检测途径。所获得的差异性蛋白峰对MCNS的早期诊断、治疗监测和寻找药物治疗的靶目标具有重要的意义。

关键词：表面增强激光解析电离-飞行时间-质谱微小病变型肾病综合征尿液生物标志物质控

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四川省某给水厂设计运行总结

城镇供水 2022年第4期 37-39页

作者：陈荣艳中国华西工程设计建设有限公司四川成都610000

通过对某给水厂四期运行效果进行比较,分析运行中存在的问题并提出相应的建议,供其他给水厂借鉴。

关键词：高浊度跑砂消毒