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Quantum interference enhanced thermopower in single-molecule thiophene junctions

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Chinese Chemical Letters 2022年第1期33卷 523-526页

作者： Hang Chen Yaorong Chen Hewei Zhang Wenqiang Cao Chao Fang Yicheng Zhou zongyuan xiao Jia Shi Wenbo Chen Junyang Liu Wenjing Hong State Key Laboratory of Physical Chemistry of Solid Surfaces iChEMCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China Beijing National Laboratory for Molecular Sciences Beijing 100190China

Quantum interference(QI)effects,which offer unique opportunities to widely manipulate the charge transport properties in the molecular junctions,will have the potential for achieving high *** we developed a scanning tunneling microscope break junction technique to investigate the thermopower through single-molecule thiophene *** observed that the thermopower of 2,4-TPSAc with destructive quantum interference(DQI)was nearly twice of 2,5-TP-SAc without DQI,while the conductance of the 2,4-TP-SAc was two orders of magnitude lower than that of 2,***,we found the thermopower was almost the same by altering the anchoring group or thiophene core in the control experiments,suggesting that the QI effect is responsible for the increase of *** density functional theory(DFT)calculations are in quantitative agreement with the experimental *** results reveal that QI effects can provide a promising platform to enhance the thermopower of molecular junctions.

关键词： Quantum interference Thermopower Thermoelectric device Single-molecule electronics Single-molecule junctions

Towards Responsive Single-Molecule Device

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Chinese Journal of Chemistry 2021年第2期39卷 421-439页

作者： Yaorong Chen Longfeng Huang Hang Chen Zhixin Chen Hewei Zhang zongyuan xiao Wenjing Hong State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China

Single-molecule devices,which are fabricated by the single molecule bridged through electrodes,provide a promising approach to investigate the intrinsic chemical or physical properties of individual *** the studies of single-molecule wires,a large number of responsive single-molecule junctions or devices with unique chemical or physical properties have been designed and fabricated by introducing the external field,which further offers the chance to explore conductive materials at the molecular ***,we summarized the latest studies on the behaviors of single-molecule devices based on the photon,thermal,electric,or magnetic responses,and discussed the development of responsive single-molecule devices in prospect.

关键词： Molecular electronics Single-molecule junction Switch External field Molecular devices

Sub-nanometer supramolecular rectifier based on the symmetric building block with destructive σ-interference

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Science China Chemistry 2021年第8期64卷 1426-1433页

作者： Longfeng Huang Yu Zhou Yaorong Chen Jingyao Ye Junyang Liu zongyuan xiao Chun Tang Haiping Xia Wenjing Hong State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhen518055China

Molecular rectifier, as a basic function of molecular electronic devices, has attracted extensive attention for the opportunity in constructing sub-nanometer electronic devices. However, tunneling leakage current has a significant contribution as electronic devices shrink in size, which leads to a challenge in fabricating molecular rectifiers at the sub-nanometer scale. Here, we experimentally demonstrate a sub-nanometer molecular rectifier based on the supramolecular junction assembled between water and 1,4-diazabicyclo[2.2.2]octane (DABCO) molecule. The charge transport through DABCO and corresponding supramolecular junctions exhibits destructive σ-interference, ensuring a sharp conductance variation for transmission modulation. The supramolecular interaction between DABCO and water readily introduces the asymmetric electrode-molecule interaction, which combines with the destructive σ-interference to support the sub-nanometer rectification.

关键词： electron transport single-molecule studies conducting material molecular devices quantum interference

串联固相萃取-液相色谱-串联质谱法测定食品中嘧啶胺类杀菌剂残留

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色谱 2012年第9期30卷 896-902页

作者：陈达捷张志刚周昱肖宗源徐敦明厦门出入境检验检疫局检验检疫技术中心福建厦门361026 厦门大学化学化工学院福建厦门361005

建立了食品中嘧啶胺类杀菌剂嘧霉胺、嘧菌胺及嘧菌环胺残留的串联固相萃取-液相色谱-串联质谱(HPLC-MS/MS)检测方法。胡萝卜、辣椒等样品经乙酸乙酯提取,石墨化炭黑-弗罗里硅藻土串联固相萃取柱(ENVI-Carb-Florisil SPE)净化后,在HPLC-M... 详细信息

建立了食品中嘧啶胺类杀菌剂嘧霉胺、嘧菌胺及嘧菌环胺残留的串联固相萃取-液相色谱-串联质谱(HPLC-MS/MS)检测方法。胡萝卜、辣椒等样品经乙酸乙酯提取,石墨化炭黑-弗罗里硅藻土串联固相萃取柱(ENVI-Carb-Florisil SPE)净化后,在HPLC-MS/MS仪上进行检测分析,采用外标法定量。质谱分析采用电喷雾电离,正离子扫描,多反应监测模式。结果表明,柱净化后无明显的基质效应,嘧霉胺、嘧菌胺和嘧菌环胺在1～20μg/L内相关系数可达0.999 0以上,具有良好的线性关系;每种杀菌剂选择两个离子对,其中一组用于定量:嘧霉胺m/z 200.1/107.1,嘧菌胺m/z 224.0/106.0及嘧菌环胺m/z 226.0/108.1;另一组用于确证:嘧霉胺m/z 200.1/183.1,嘧菌胺m/z 224.0/131.1和嘧菌环胺m/z 226.0/133.1。样品中添加0.1、0.5、1.0μg/kg的标准品,其回收率为73.2%～98.7%,相对标准偏差(n=10)小于10%;嘧霉胺、嘧菌胺、嘧菌环胺的检出限(信噪比(S/N)=3)均为0.03μg/kg;嘧霉胺、嘧菌胺、嘧菌环胺的定量限(S/N=10)均为0.1μg/kg。实验结果表明,该方法提取效果好,具有良好的灵敏度、回收率和重复性。

关键词：高效液相色谱-串联质谱法串联固相萃取嘧啶胺类杀菌剂食品

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化工原理实验线上线下混合教学的实践研究

化工高等教育 2022年第2期39卷 137-141页

作者：车黎明苏玉忠陈学云肖宗源李薇厦门大学化学化工学院化学工程与生物工程系福建厦门361005

为了解决传统实验教学中存在的问题,厦门大学进行了化工原理实验线上线下混合教学实践。在线上线下混合教学模式下,学生在课前通过观看教学视频预习实验,并以预习演示文稿代替手写预习报告;课堂教学以“学生汇报+讨论+教师点评”的方式... 详细信息

为了解决传统实验教学中存在的问题,厦门大学进行了化工原理实验线上线下混合教学实践。在线上线下混合教学模式下,学生在课前通过观看教学视频预习实验,并以预习演示文稿代替手写预习报告;课堂教学以“学生汇报+讨论+教师点评”的方式代替教师讲授。问卷调查结果表明,线上线下混合教学显著增加了学生的预习时长,改善了预习效果,活跃了课堂气氛,有利于锻炼学生的自学能力和团队协作能力,对国内其他高等院校化工原理实验的教学改革具有一定的参考价值。

关键词：化工原理实验线上教学线下教学

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气液传质界面湍动现象投影观察

化工学报 2010年第4期61卷 844-847页

作者：沙勇李樟云林芬芬吐松肖宗源叶李艺厦门大学化学化工学院福建厦门361005

In gas-liquid mass transfer processes,interfacial turbulence may occur due to the surface tension gradient and the density gradient produced by mass transfer near the *** interfacial turbulence can enhance the mass transfer since it intensifies the movement of interfacial *** means of the shadowgraph optical method,the interfacial turbulence patterns vertical to the interface were observed directly in the volatilization process of binary *** images of the amplified interfacial turbulence showed the variation of concentration and the fluid movement under the *** patterns of interfacial turbulence were observed in the experiments:plume and *** the plume,the interfacial fluid moved slowly and penetrated the liquid *** the vortex,the interfacial turbulence occurred in the vicinity of the liquid interface and the fluid moves quite fast.A qualitative analysis was carried out based on the mechanism of Rayleigh-Bénard convection induced by density gradient and Marangoni convection induced by surface tension gradient.

关键词：投影界面湍动传质 Marangoni对流 Rayleigh-Bénard对流

硼改性酚醛树脂的合成及其模塑料力学性能研究

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材料导报 2015年第16期29卷 52-57页

作者：易新龙冯安妮邵文尧肖宗源厦门大学化学化工学院厦门361005

研究了硼酸加入量对所合成硼改性酚醛树脂性能的影响。通过红外光谱和热重等分析手段对硼改性酚醛树脂的结构和热性能进行表征,分别考察其在氮气和空气氛围下的残炭率,获知当苯酚、甲醛和硼酸之间的物质的量比为1∶1.4∶0.4时,硼改性酚... 详细信息

研究了硼酸加入量对所合成硼改性酚醛树脂性能的影响。通过红外光谱和热重等分析手段对硼改性酚醛树脂的结构和热性能进行表征,分别考察其在氮气和空气氛围下的残炭率,获知当苯酚、甲醛和硼酸之间的物质的量比为1∶1.4∶0.4时,硼改性酚醛树脂的残炭率最高,分别为67.82%和10.92%。此外,以硼改性酚醛树脂为基体树脂制备模塑料并考察其拉伸强度、弯曲强度和抗冲击强度等力学性能。综合考虑以上热性能和力学性能,确定苯酚、甲醛和硼酸之间的最佳物质的量比为1∶1.4∶0.3。最后,研究了添加不同种类和不同含量的填料对酚醛模塑料力学性能的影响。研究结果表明:以短玻璃纤维为填料时,酚醛模塑料的力学性能优于木粉和长玻璃纤维混合物填料;若使用木粉和长玻璃纤维混合物填料,当木粉与长玻璃纤维的质量比为1∶3时,酚醛模塑料的力学性能最佳。

关键词：硼改性酚醛树脂红外光谱热性能力学性能模塑料

竖直流动皂膜中解吸导致的Marangoni对流观察

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化工学报 2010年第5期61卷 1123-1126页

作者：沙勇李樟云江桂仙吐松肖宗源叶李艺厦门大学化学化工学院福建厦门361005

In gas-liquid mass transfer processes,Marangoni convection may occur due to the surface tension gradient produced by mass transfer near the *** a falling soap film tunnel and the Schlieren optical method,the Marangoni convection patterns along the film surface were observed directly in the desorption process of acetone from the falling soap *** Schlieren images showed the regular roll convection in the thin falling soap film during the acetone *** hydraulic characteristics were determined experimentally by measuring the variation of acetone concentration in the film and the surface tension of the soap *** results show that the acetone concentration gradient vertical to the falling direction is very small because the thickness of the soap film is in the order of 10-6 *** variation of acetone concentration along the falling film is large,so there is a significant surface tension gradient,resulting in the Marangoni roll *** experimental results and a qualitative analysis may be helpful to understand the mechanism of Marangoni convection near the interface in the mass transfer.

关键词： Marangoni对流传质纹影皂膜

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高反射比纳米TiO_2的制备

化工新型材料 2011年第5期39卷 88-91页

作者：李国栋陈秉辉黄佳龙肖宗源厦门大学化学化工学院厦门361005

采用溶胶-凝胶法制备纳米TiO2,利用紫外-可见-近红外分光光度计测定样品在400~2500 nm的反射率。系统研究了制备条件对样品反射率的影响,并确定了最佳制备条件。所制备的纳米TiO2粉体的平均反射率大于110%,明显高于市售的太阳热反射粉,... 详细信息

采用溶胶-凝胶法制备纳米TiO2,利用紫外-可见-近红外分光光度计测定样品在400~2500 nm的反射率。系统研究了制备条件对样品反射率的影响,并确定了最佳制备条件。所制备的纳米TiO2粉体的平均反射率大于110%,明显高于市售的太阳热反射粉,该粉体能够作为良好的太阳热反射涂料颜填料。

关键词：纳米TiO2 测定反射比溶胶-凝胶法太阳热反射涂料