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pH-Sensitive Polymer Matrix with Immobilized Indicator Ion Pairs

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Chemical Research in Chinese Universities 2002年第1期18卷 8-11页

作者： guo Liang-qia NIE Qiu-yan XIE Zeng-hong chen Yi-ting chen guo-nan chen Xi WANG Xiao-ru Department of Chemistry Fuzhou UniversityFuzhou 350002P.R.China Department of Chemistry Xiamen UniversityXiamen 361005P.R.China

A new sensor material for monitoring pH in aqueous solutions is described. It is based on lipophilic ion pairs consisting of an anionic pH indicator Bromocresol Green and a quaternary ammonium cation cetyltri-methylammonium. The ion pairs are homogeneously distributed inside the plasticized PVC membrane. The change of pH in an aqueous solution causes the change of optical property of the indicator immobilized on the plasticized PVC membrane. The plasticized PVC membrane is sensitive in a pH range from 4.0 to 6.0.

关键词： Bromocresol green pH PVC membrane

Novel Phosphate-sensitive Fluorescent Composite Matrix

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Chemical Research in Chinese Universities 2003年第2期19卷 201-205页

作者： XIE Zeng hong LIN Xu cong chen guo nan Department of Chemistry Fuzhou UniversityFuzhou 350002P.R.China

Via several techniques to modify sensitive matrix for inhabiting the leakage of fluorescent indicator, a new stable sensing material for monitoring phosphates has been prepared and applied to the measurement of phosphates in artificial seawater. It is based on the reaction of PO 3- 4 with Al(Ⅲ) Morin that leads to the fluorescence quenching of the composite matrix. At pH value 4 0 and the salinity value 25 0, the response time of output signal having reached the steady state is less than 300 seconds. Its calibration graph is gained in the range of H 2PO - 4 mass concentration from 1 50 to 7 00 μg/mL with the limit of detection(3 σ/K ) 0 02 μg/mL. When it was used to measure phosphates in artificial seawater, the recovery ranged from 96 78% to 102 09%. Being stored under the proper condition, the membranes maintain sensitive for 90-120 days, and are able to be used for 50-80 times with indicator supplement.

关键词： PVA/PVC composite membrane Phosphate Al-Morin

Determination of N-Methylcarbamate Pesticides in Vegetables by Solid-phase Extraction and Pressurized Capillary Electrochromatography

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Chemical Research in Chinese Universities 2007年第1期23卷 109-115页

作者： WU Xiao-ping WANG Ling XIE Zeng-hong YAN Chao chen guo-nan Key Laboratory of Food Safety Analysis and Detection Technology of MOE Department of Chemistry Fuzhou University Fuzhou 350002 P. R. China Unimicro Technologies Inc. Pleasanton CA94566 USA

Capillary electrochromatography （CEC） is a hybrid technique that couples the good selectivity of high-performance liquid chromatography （HPLC） and the high separation efficiency of capillary electrophoresis （CE）. Both charged and uncharged compounds can be separated effectively using CEC. In some cases, however, the bubbles that generated in the capillary column in pure CEC performed on commercial CE instruments will cause unstable current and even disrupt the separation when the concentration of buffer is very high. By applying pressure on the electrochromatographic separation via a micro-HPLC pump, pressurized capillary electrochromatography （ pCEC ） combines two driving factors of the electroosmotic flow （EOF） and the pressure flow, thereby increasing the speed and the selectivity of separation and suppressing the bubble formation. Moreover,

关键词： Pressurized capillary electrochromatography N-Methylcarbamate Pesticide Solid-phase extraction

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

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Journal of Energy Chemistry 2025年第1期100卷 533-543页

作者： Zewen Liu Zhen Wu Hao Wang Xudong Zhang Yuanzhen chen Yongning Liu Shengwu guo Shenghua chen Yanli nan Yan Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp Ltd Network Information Center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558Co0.074O2（L1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li1.2Ni0.13Mn0.54Co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

关键词： Ice

胶束毛细管电动色谱法用于DNA碱基腺嘌呤和嘌呤类抗癌药物的研究

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高等学校化学学报 2005年第8期26卷 1437-1439页

作者：张兰李瑞宝童萍陈国南福州大学化学化工学院福州350002

The adenine, 8-hypoxanthine, 6-thioguanine and 8-azaguanine were separated and determined with the method of micellar electrokinetic capillary chromatography. The optimal conditions of electrophoresis were studied. At 25 ℃ and 20 kV applied voltage, the four components were baseline separated within 16 min in 25 mmol/L phosphate-borate buffer（pH=7.0） including 30 mmol/L SDS at the detection wavelength of 210 nm. The peek area versus concentration was linear over the concentration range of （12200）×10{-6} mol/L for 8-hypoxanthine and 8-azaguanine, and （6.5100）×10{-6} mol/L for adenine and 6-thioguanine. The detection limits of all analytes mentioned above attained to 10{-6} mol/L grade. And the correlationg coefficients of four analytes were over 0.998 5. In the real sample of the mean absolute recoveries of 8-hypoxanthine, adenine, 6-thioguanine and 8-azaguanine were 97.2%{102.1%}, and the relative standard deviations for the four components were less than 3.41%（n=5）. The method is rapid, simple with a good solution for the analysis of 8-hypoxanthine, adenine, 6-thioguanine and 8-azaguanine, and satisfactory results were obtained.

关键词：胶束毛细管电动色谱法腺嘌呤 8-羟基嘌呤 6-巯基嘌呤 8-氮杂鸟嘌呤

Analysis of Micromechanical Properties at the Interface of Pre-wet SBS Modified Asphalt Mixture Based on Molecular Simulation Technology

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 103-113页

作者： chen Wuxing chen Shuang YU Yan ZHANG Jiangyi XU Haiyang guo Wei School of Mines China University of Mining and TechnologyXuzhou 221000China College of Construction Engineering Jilin Uni-versityChangchun 130026China

The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and *** effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics *** diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are *** simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are *** concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more *** to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after *** to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.

关键词： pre-wet oil-stone interface interface interaction interface mechanics molecular dynamics simulation

10,10′-二甲基-3,3′-二磺酸基-9,9′-双吖啶的电致化学发光行为

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物理化学学报 2007年第10期23卷 1589-1593页

作者：黄风华庄惠生陈国南福州大学食品安全分析与检测教育部重点实验室东华大学环境科学与工程学院上海200051

研究了新试剂10,10′-二甲基-3,3′-二磺酸基-9,9′-双吖啶(简称DMDSBA)的电致化学发光(ECL)行为.考察了电化学参数、反应介质以及pH等条件对DMDSBA电致化学发光信号的影响.结果表明,在玻碳电极上施加适当电压时,DMDSBA在KNO3溶液介质... 详细信息

研究了新试剂10,10′-二甲基-3,3′-二磺酸基-9,9′-双吖啶(简称DMDSBA)的电致化学发光(ECL)行为.考察了电化学参数、反应介质以及pH等条件对DMDSBA电致化学发光信号的影响.结果表明,在玻碳电极上施加适当电压时,DMDSBA在KNO3溶液介质中产生很强的电致化学发光信号,于优化的实验条件下,发光强度的自然对数与DMDSBA浓度的自然对数在1.0×10-5-1.0×10-8mol·L-1范围内呈良好的线性关系,DMDSBA的检出限可达2.3×10-9mol·L-1.用循环伏安法、电致化学发光光谱以及荧光光谱,研究了DMDSBA的电致化学发光机理.

关键词： 10,10′-二甲基-3,3′-二磺酸基-9,9′-双吖啶电致化学发光机理

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缆索结构系统动态响应的轴向主动刚度控制

东南大学学报（自然科学版） 1999年第6期29卷 66-69页

作者：陈南郭希红东南大学机械工程系南京210096

研究一种索缆类结构系统动态响应的有源的轴向主动刚度控制技术．通过沿缆索轴向设计产生一个主动动态位移导致缆索系统的横向刚度变化并产生附加阻尼，使缆索的横向振动幅值减少．通过模拟装置实验，验证了开环地施加这种控制，可获得... 详细信息

研究一种索缆类结构系统动态响应的有源的轴向主动刚度控制技术．通过沿缆索轴向设计产生一个主动动态位移导致缆索系统的横向刚度变化并产生附加阻尼，使缆索的横向振动幅值减少．通过模拟装置实验，验证了开环地施加这种控制，可获得预计的减少振动的效果．

关键词：振动控制主动刚度控制缆索结构系统动态响应

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铱配合物的电致化学发光性能研究

分析化学 2011年第7期39卷 1109-1112页

作者：魏巧华韩李静段亚男肖方南陈裕松张兰陈国南福州大学食品安全与检测技术教育部重点实验室化学化工学院

结构相关的铱配合物[Ir(ppy)2L1](PF6)和[Ir(ppy)2L2](PF6)(ppy=2-苯基吡啶,L1=4-(2,2’-联吡啶-3-乙炔基)-N-(吡啶-2-亚甲基)-N-(噻吩-3-亚甲基)苯胺,L2=4-(2,2’-联吡-3-乙炔基)-N-二(吡啶-2-亚甲基)-苯胺)都具有优良的电致发光(ECL)性能。在玻碳电极上,以TPrA为共反应物,其ECL电压分别在1.52和1.36 V左右,其最强的ECL发射波长在620～640 nm,且发光强度(IECL)与其浓度分别在0.2～1.6μmol/L和0.02～2μmol/L范围内呈良好的的线性关系。在相同条件下,配合物[Ir(ppy)2L2](PF6)/TPrA体系的ECL强度比[Ir(ppy)2L1](PF6)强,与[Ru(bpy)3]2+/TPrA体系相当。

关键词：铱配合物电致化学发光