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Chemical Research in Chinese Universities 2014年第2期30卷 205-210页

作者： XU Huanhuan WANG Xueliang CHEN Rong yu zhangyu Department of Chemistry and Chemical Engineering Qufu Normal University Qufu 273165 P.R.China Department of Chemistry and Chemical Engineering Heze University Heze 274015 P.R.China

A hybrid membrane consisted of aminated graphene and Ag nanoparticles（Ag NPs） was prepared on the surface of glassy carbon electrode（GCE） by cyclic voltammetry（CV） with aminated graphene（GR-NH2） as matrix for immobilizing Ag *** morphology and electrochemical properties of this hybrid membrane were characterized by scanning electron microscopy（SEM） and CV,respectively,and on this membrane,the voltammetric behaviors of epinephrine（EP） were studied in *** membrane exhibited excellent eletro-catalytic activities for the redox of EP,and could resolve the electrochemical response of EP and uric acid（UA） into two oxidation *** peak current of EP was linear with its concentration in the ranges of 0.916-18.3 μmol/L and 18.3-184 μmol/*** detection limit was 2.0 nmol/L（S/N=3）.The proposed modified electrode retained the advantages of easy fabrication,high sensitivity and good repeatability for the determination of EP.

关键词： Ag nanoparticle(Ag NP) Aminated graphene(GR-NH2) Epinephrine(EP) Uric acid(UA) Cyclic voltammetry(CV)

Mechanistic Study on site-selective C.H（C-4/C-8）alkynylation of isoquinolones catalyzed by gold and rhodium catalysts

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Mechanistic Study on site-selective C.H（C-4/C-8）alkynylati...

DFT Calculations of the Rhodium-Catalyzed Oxidative C-H Allylation of Benzamides with 1,3-Dienes by Ally-to-Ally 1,4-Rh（Ⅲ） Migration

第十三届全国量子化学会议

作者： Fengyue Zhao Shaojing liu Yaping Li Shumin Han Tao Liu zhangyu yu School of Chemistry and Chemical Engineering Qufu Normal University Department of Chemistry and Chemical Engineering Jining University

The isoquinolones have caused widespread concern because of its specific structural motifs [1]. The method of the transition metal catalyzed C-H functionalization has become quite perfect and use this method can quickly form a variety of isoquinolinones. Recently, Aslam and co-workers[2] was reported a site-selective（C-4/C-8） alkynylation of isoquinolones enabled by gold and rhodium complexes. Although the Aslam group has made a plausible mechanical pathway, the key issues still need further discussion.（1） What is the detailed reaction mechanism?（2） What is the origin of site-selective C-H alkynylation of isoquinolones catalyzed by gold and rhodium catalysts?Here we would like to report our detailed density functional theory（DFT）calculations on the reaction *** expect this work would help understand the detailed mechanisms and design new related reactions.

关键词： reaction mechanism site-selective

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DFT Calculations of the Rhodium-Catalyzed Oxidative C-H Ally...

第十三届全国量子化学会议

作者： Shaojing liu Fengyue Zhao Yaping Li Shumin Han Tao Liu zhangyu yu School of Chemistry and Chemical Engineering Qufu Normal University Department of Chemistry and Chemical Engineering Jining University

Allylmetal species are important intermediates in organic synthesis.[1] Recently, Stamatis E. Korkis and co-workers[2] first reported allyl-to-allyl 1,4-Rh（III） migration in the oxidative C-H allylation of benzamides with 1,3-dienes which is different to the characteristic reaction we known that 1,3-transposition of the metal from one end of the allylic fragment to the *** process could serve as a valuable addition to the currently limited number of catalytic C-H functionalizations involving 1,*** a plausible mechanistic pathway has been proposed by Stamatis E. Korkis group,key issues still need to be further discussed. What is the detailed reaction mechanism? Here we would like to report our detailed density functional theory（DFT） calculations on the reaction *** expect this work would help understand the detailed mechanisms and design new related reactions.

关键词： reaction mechanism DFT Calculations

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石墨烯/铂纳米粒子杂化膜测定肾上腺素

应用化学 2014年第12期31卷 1465-1471页

作者：郭宪厚王学亮郁章玉菏泽学院化学化工系菏泽274000 枣庄矿业集团宏达化工有限公司滕州277500 济宁学院曲阜273165

利用循环伏安法制备了石墨烯/铂纳米粒子杂化膜修饰电极,并利用该修饰电极研究了肾上腺素（EP）的电化学行为,建立了测定肾上腺素的电化学方法。分别利用扫描电子显微镜和循环伏安法对电极的表面形貌和电化学性能进行了表征,优化了修饰... 详细信息

利用循环伏安法制备了石墨烯/铂纳米粒子杂化膜修饰电极,并利用该修饰电极研究了肾上腺素（EP）的电化学行为,建立了测定肾上腺素的电化学方法。分别利用扫描电子显微镜和循环伏安法对电极的表面形貌和电化学性能进行了表征,优化了修饰电极制备过程中影响电极性能的条件和EP的测定条件。结果表明,石墨烯/铂纳米粒子修饰电极对肾上腺素有明显的电催化作用。在p H=5.0的柠檬酸-磷酸氢二钠缓冲溶液中,EP的氧化峰电流与其浓度在4.4×10^-8~2.2×10^-6mol/L的范围内呈良好的线性关系。线性方程为ipa（10 A）=0.0753c（mol/L）＋3.7653×10^-5,r=0.9989,检出限为2.2×10^-9mol/L（S/N=3）。修饰电极表具有良好的重现性,可用于实际样品的测定。

关键词：石墨烯铂纳米粒子杂化材料肾上腺素应用

火麻叶中大麻二酚提取工艺的响应面法优化及不同部位含量分布

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天然产物研究与开发 2024年第3期36卷 369-376,399页

作者：张一宁于志琪屈施旭刘同歌张玉红东北林业大学森林植物生态学教育部重点实验室黑龙江省林源活性物质生态利用重点实验室哈尔滨150040

本文研究一种超声波辅助提取火麻叶中大麻二酚(cannabidiol,CBD)的方法,同时分析火麻不同部位的CBD含量。首先建立CBD的HPLC检测方法,采用单因素实验确定超声提取功率、提取温度、提取时间、料液比4个因素对火麻叶中CBD提取率的影响;利... 详细信息

本文研究一种超声波辅助提取火麻叶中大麻二酚(cannabidiol,CBD)的方法,同时分析火麻不同部位的CBD含量。首先建立CBD的HPLC检测方法,采用单因素实验确定超声提取功率、提取温度、提取时间、料液比4个因素对火麻叶中CBD提取率的影响;利用Design-expert软件进行Box-Benhnken实验设计确定并验证CBD的超声辅助提取的最优工艺条件,并检测火麻不同部位CBD含量。实验表明:采用Agilent HC-C_(18)柱(250 mm×4.6 mm,5μm),检测波长:220 nm,流速:1.0 mL/min,柱温:28℃,流动相:甲醇-水=90∶10,等度洗脱,在此条件下的分离效果和峰型较好,并且结果准确可靠,稳定性好。以甲醇为提取溶剂,最佳提取工艺条件为:提取功率320 W,提取温度81℃,提取时间26 min,料液比1∶22 g/mL,在此条件下得到CBD含量的平均值为79.53±0.26 mg/g。火麻嫩叶中CBD含量最高,其余依次为老叶、种子和茎,根中含量最低。结果表明,超声波提取是一种高效的大麻二酚提取方法,且作为一种天然产物资源,大麻二酚具有重要的开发利用价值。

关键词：大麻二酚火麻叶超声辅助提取高效液相色谱响应面

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溶液中铁含量的测定方法综述

云南化工 2023年第11期50卷 20-23页

作者：余张玉吴立群王昭沛刘其峰邵凡曲靖市德枋亿伟有限公司云南曲靖655000 曲靖市德方纳米科技有限公司云南曲靖655000

综述了溶液中常见铁含量的测定方法,包括重铬酸钾容量法、分光光度法、络合滴定法、原子吸收光谱法、ICP光谱法、X射线荧光光谱法、极谱法等,并对各种方法的优缺点和适用范围进行了分析和比较。

关键词：铁离子定量分析综述

Mesoscopic Modeling Approach and Application for Steel Fiber Reinforced Concrete under Dynamic Loading:A Review

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Engineering 2022年第9期16卷 220-238页

作者： Jinhua Zhang zhangyu Wu Hongfa yu Haiyan Ma Bo Da School of Civil Engineering Southeast UniversityNanjing 210096China Department of Civil and Airport Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Science and Technology on Near-Surface Detection Laboratory Wuxi 214035China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

Steel fiber reinforced concrete(SFRC)has drawn extensive attention in recent years for its superior mechanical response to dynamic and impact *** on the existing test results,the highstrength steel fibers embedded in a concrete matrix usually play a strong bridging effect to enhance the bonding force between fiber and the matrix,and directly contribute to the improvement of the post-cracking behavior and residual strength of *** gain a better understanding of the action behavior of steel fibers in matrix and further capture the failure mechanism of SFRC under dynamic loads,the mesoscopic modeling approach that assumes SFRC to be composed of different mesoscale phases(i.e.,steel fibers,coarse aggregates,mortar matrix,and interfacial transition zone(ITZ))has been widely employed to simulate the dynamic responses of SFRC material and structural *** paper presents a comprehensive review of the state-of-the-art mesoscopic models and simulations for SFRC under dynamic *** approaches for the SFRC mesoscale model in the simulation works,including steel fiber,coarse aggregate,and the ITZ between them,are reviewed and compared *** material models for different phases and the interaction relationship between fiber and concrete matrix are summarized ***,some example applications for SFRC under dynamic loads(i.e.,compression,tension,and contact blast)simulated using the general mesoscale models are ***,some critical analysis on the current shortcomings of the mesoscale modeling of SFRC is highlighted,which is of great significance for the future investigation and development of SFRC.

关键词： Steel fiber reinforced concrete Mesoscale modeling Dynamic loading Materials model Interfacial characteristic

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用光透薄层电池测定式电极电势和电子转移数

曲阜师范大学学报（自然科学版） 1989年第3期15卷 65-68页

作者：郁章玉顾登平曲阜师大河北师大

本文介绍了光谱电化学的基本原理。用循环伏安法和薄层光谱电化学技术研究了最近合成的冠醚配会物[Fe(NCS)_3(H_2O)_3](18—C—6)在二甲基亚砜中的阴极还原。测定了n=0.9,E^0′=0.23VvsSCE。推测了溶液中配合物的氧化态和还原态的存在... 详细信息

本文介绍了光谱电化学的基本原理。用循环伏安法和薄层光谱电化学技术研究了最近合成的冠醚配会物[Fe(NCS)_3(H_2O)_3](18—C—6)在二甲基亚砜中的阴极还原。测定了n=0.9,E^0′=0.23VvsSCE。推测了溶液中配合物的氧化态和还原态的存在形式。

关键词：光谱电化学冠醚配合物薄层电极

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静电对果蔬热风干燥特性的影响

食品与发酵工业 2020年第6期46卷 217-223页

作者：王烽先刘寅孟照峰于彰彧王航闫俊海中原工学院能源与环境学院河南郑州451191 河南中瑞制冷科技有限公司河南郑州451191

采用单因素实验法,选取样品切片5 mm,55℃的干燥条件下研究静电装置对胡萝卜、香蕉的热风干燥特性。实验对样品的干湿基含水率、干燥速率、脱水率的变化情况进行了分析。结果表明,在进行热风干燥的同时添加静电装置提高果蔬前期干燥速... 详细信息

采用单因素实验法,选取样品切片5 mm,55℃的干燥条件下研究静电装置对胡萝卜、香蕉的热风干燥特性。实验对样品的干湿基含水率、干燥速率、脱水率的变化情况进行了分析。结果表明,在进行热风干燥的同时添加静电装置提高果蔬前期干燥速率与脱水率,最多可缩短干燥时间16.67%,降低能耗17%,复水率提升14%。物料初始含水率越高,静电装置的作用越明显。对数据进行了数学拟合,决定系数R 2、均方根误差RMSE分别为0.9908~0.9983、0.01128~0.02282,证实了Weibull分布函数模型适合静电装置联合热风干燥。静电装置具有抑制微生物生长、提升干燥品质的作用,且静电装置耗能低,辅助干燥效果明显,在食品干燥方面有着广阔的应用前景。

关键词：静电装置果蔬干燥特性热风干燥 Weibull

Three-Dimensional Mesoscopic Investigation on the Impact of Specimen Geometry and Bearing Strip Size on the Splitting-Tensile Properties of Coral Aggregate Concrete

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Engineering 2022年第10期17卷 110-122页

作者： zhangyu Wu Jinhua Zhang Hongfa yu Qin Fang Haiyan Ma Li Chen Department of Civil and Airport Engineering Civil Aviation CollegeNanjing University of Aeronautics and AstronauticsNanjing 210016China School of Civil Engineering Southeast UniversityNanjing 210096China Engineering Research Center of Safety and Protection of Explosion and Impact of Ministry of Education(ERCSPEIME) Southeast UniversityNanjing 211189China Army Engineering University of PLA Nanjing 210007China

The use of coral aggregate concrete(CAC)as a novel construction material has attracted significant attention for the construction of reef engineering *** investigate the static splitting-tensile behaviors of CAC under the influence of two factors,namely specimen geometry and bearing strip size,a three-dimensional(3D)mesoscale modeling approach with consideration for aggregate randomness in shape and distribution was adopted in this *** established 12 different specimen models with two specimen shapes(i.e.,a cube with an edge length of 150 mm and a cylinder with dimensions ofφ150 mm×300 mm)and six strip widths(i.e.,6,9,12,15,18,and 20 mm)for *** effects of specimen geometry and strip width on the splitting-tensile properties of CAC,such as failure processes,final failure patterns,and splitting-tensile strength(fst),are analyzed and discussed *** results indicate the high reliability of the developed mesoscale modeling approach and reveal the optimal computational parameters for simulating and predicting the splitting-tensile properties of *** fstvalues of CAC are associated with both the specimen geometry and width of the bearing *** fstvalues of the cube model are slightly higher than those of the cylinder model for the same bearing strip size,representing geometry effects that can be explained by differences in fracture ***,the fstvalue of CAC gradually increases with the relative width of the bearing strip ranging from 0.04 to *** on the elastic solution theory,the variation area of CAC fstvalues with the relative width of the bearing strip was determined preliminarily,which has great significance for studying the tensile performance of CAC.

关键词： Coral aggregate concrete 3D mesoscopic modelling Splitting-tensile test Tensile strength Specimen geometry Bearing strip