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A fluorescent probe based on a spiropyran for sensitive detection of Ce^3+ ion

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Journal of Rare Earths 2020年第4期38卷 445-450页

作者： Xin Luo Dongling Chen Zhenxiang Xu yanxi song Hongqi Li Chunying Xian Key Laboratory of Science&Technology of Eco-Textile Ministry of EducationCollege of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China Weifang Institute of Test and Measurement Weifang 261000China Penglai Xinguang Pigment Chemical Co. Ltd.Penglai 265600China School of Environmental Science and Engineering Donghua UniversityShanghai 201620China

A spiropyran-based probe was *** serves as a fluorescence turn-on probe for selective detection of Ce^3+in both ethanol and aqueous(water/ethanol,1:9 or 9:1,v/v)***3+can induce photochromism of the probe though the probe exhibits negligible photochromic property by *** probe is sensitive to Ce3+and the detection limit reaches 1.7μmol/*** exhibits a high selectivity for Ce^3+ion over other common metal cations including Li^+,Na^+,Ag^+,Sr^2+,Ni^2+,Co^2+,Hg^2+,Zn^2+,Cr^3+,Al^3+,Fe^3+and Bi^3+and lanthanide ions Nd^3+,Yb^3+and La^3+.The probe may be used for quantitative determination of the concentration of Ce3+ion in a range of 1-10μmol/L and for application to environmental water *** mechanism of the probe towards Ce3+ion is proposed.

关键词： Spiropyran Probe Cerium(Ⅲ)ion Fluorescent Rare earths

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脉冲热管温度时间序列的非线性混沌分析

化工学报 2008年第10期59卷 2470-2477页

作者：宋延熙徐进良中国科学院广州能源研究所广东广州510640

Temperature oscillation signal of pulsating heat pipes was studied quantitatively and qualitatively by means of analyses of power spectrum,auto-correlation function,correlation dimension,Kolmogorov entropy and rescaled range statistical *** results showed that the system had deterministic chaotic characteristics which featured non-integer value of correlation dimension about 2.5—11 and positive Kolmogorov *** Hurst exponents were between 0.8 and 1,indicating long range *** performance was tied with correlation *** correlation dimension indicated lower thermal resistance.

关键词：脉冲热管传热性能混沌关联维

Liquid Chromatographic Resolution of Racemic ?-Amino Acids,Amines and Amino Alcohols on Two New Improved Chiral Crown Ether Stationary Phases

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Liquid Chromatographic Resolution of Racemic ?-Amino Acids,A...

第21届全国色谱学术报告会及仪器展览会

作者： song yanxi Li Hongqi Hyun Myung Ho Cho Yoon Jae School of Environmental Science and Engineering Donghua University College of Chemistry Chemical Engineering & BiotechnologyDonghua University Pusan National University

Two doubly tethered aminoalkyl chiral crown ether stationary phases were prepared by covalently bonding（+）-（18-crown-6）-2,3,11,12-tetracarboxylic acid to doubly tethered aminoalkyl silica gel in order to improve the stability and the enantioselectivity of chiral stationary phases（CSPs） based on（+）-（18-crown-6）-2,3,11,12-tetracarboxylic acid developed previously in our lab. The chiral recognition behavior of the new CSPs was investigated by using racemic primary amino compounds with the variation of the type and content of organic and acidic modifiers in mobile phase and the column temperature. The stability of the CSPs was examined. The results revealed that the new CSPs were more effective in resolving various racemic ?-Amino Acids, Amines and Amino Alcohols than the original ones. Meanwhile, the CSPs showed excellent stability after a month of use.

关键词： Chiral stationary phase Crown ether Enantiomer separation Liquid chromatography

来源： cnki会议评论

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体液直接进样固定相的研究进展

分析化学 1999年第2期27卷 230-236页

作者：宋燕西刘满仓朱彭龄兰州大学化学系兰州大学化学系兰州730000

评述了生物体液直接进样高效液相色谱固定相的制备、结构性能及应用.其特点可概括为:只允许生物体液中蛋白质等大分子物质与亲水的生物相容的固定相表面接触,使其在柱中无保留地洗脱,而小分子物质可获得保留.达到直接进样分析的目的.

关键词：高效液相色谱限进介质生物体液直接进样评述

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含卤素取代基四硫富瓦烯的合成与研究进展

有机化学 2009年第6期29卷 858-866页

作者：李洪启宋燕西李秀梅东华大学化学化工与生物工程学院上海201620 东华大学环境科学与工程学院上海201620 内蒙古通辽职业学院理工系通辽028000

简要概括了含卤素取代基四硫富瓦烯(TTF)衍生物的主要合成方法,即TTF及其衍生物的直接卤化法以及卤代1,3-二硫杂环戊烯-2-(硫)酮在亚磷酸三烷基酯参与下的偶合反应.介绍了含卤素TTF衍生物的电化学、结晶和成膜性能,及其作为重要的合成... 详细信息

简要概括了含卤素取代基四硫富瓦烯(TTF)衍生物的主要合成方法,即TTF及其衍生物的直接卤化法以及卤代1,3-二硫杂环戊烯-2-(硫)酮在亚磷酸三烷基酯参与下的偶合反应.介绍了含卤素TTF衍生物的电化学、结晶和成膜性能,及其作为重要的合成中间体在构筑给体-受体二元体、低聚TTF体系、含TTF单元的环蕃、含TTF单元的聚合物以及各种官能化TTF衍生物中的应用.提出了含卤素TTF衍生物的研究发展趋势.

关键词：四硫富瓦烯卤素取代基合成电化学性能合成中间体

新型基础设施建设对地区出口的影响——来自国家智慧城市试点的证据

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产业经济研究 2022年第5期 115-128页

作者：周记顺宋颜希华中科技大学经济学院湖北武汉430074

新型基础设施建设的战略地位日益攀升,对我国出口高质量增长有着重要影响。在出口新旧动能转换的现实背景下,将国家智慧城市试点作为我国新型基础设施建设的一项准自然实验,基于2005—2016年中国282个地级市面板数据,采用双重差分法检... 详细信息

新型基础设施建设的战略地位日益攀升,对我国出口高质量增长有着重要影响。在出口新旧动能转换的现实背景下,将国家智慧城市试点作为我国新型基础设施建设的一项准自然实验,基于2005—2016年中国282个地级市面板数据,采用双重差分法检验了智慧城市建设对城市出口的影响。研究发现,智慧城市建设能够显著提升城市出口规模,且主要通过信息成本效应、资源配置效应和技术创新效应来推动出口规模增长。智慧城市建设主要通过本地的贸易创造推动出口增长,而对周围城市的出口规模没有显著影响,即并未表现出显著的辐射效应或虹吸效应。进一步研究发现,智慧城市建设能有效带动城市出口的转型升级,具体表现为一般贸易出口占比、资本和技术密集型产品出口占比以及出口产品质量的提高。结论丰富了新型基础设施的经济效应研究,对于畅通国内国际双循环以及打造出口新动能具有重要意义。

关键词：新型基础设施建设智慧城市双重差分出口贸易转型升级双循环

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

企业生命周期视角下盈余管理方式研究——基于债务契约理论

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管理评论 2016年第12期28卷 75-91页

作者：王云李延喜宋金波马壮大连理工大学管理与经济学部辽宁116024

本文基于债务契约理论研究不同企业生命周期下企业盈余管理及方式问题,运用现金流量法把中国上市公司划分为成长期、成熟期和衰退期企业,并选取2001-2012年的数据为样本,研究企业生命周期、资本结构对盈余管理及方式的影响。研究发现:... 详细信息

本文基于债务契约理论研究不同企业生命周期下企业盈余管理及方式问题,运用现金流量法把中国上市公司划分为成长期、成熟期和衰退期企业,并选取2001-2012年的数据为样本,研究企业生命周期、资本结构对盈余管理及方式的影响。研究发现:相比于成熟期,成长期和衰退期企业负债结构更高;负债水平显著正向影响企业盈余管理,随着生命周期的延伸,负债对盈余管理的影响程度增强;生命周期直接影响企业盈余管理,相对成熟期,成长期和衰退期都正向影响应计与真实盈余;生命周期对债务水平与盈余管理的关系产生调节作用,相对于成熟期,随着负债的增加成长期企业倾向减少应计盈余,但衰退期企业会增加更为隐蔽,成本更高的真实盈余管理方式。

关键词：企业生命周期资本结构债务契约盈余管理

Identification of Linear Systems Using Binary Sensors with Random Thresholds

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Journal of Systems Science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang School of Mathematics Renmin University of ChinaBeijing 100872China School of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification