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Chemical Research in Chinese Universities 2005年第4期21卷 401-405页

作者： lügui-qin DUJin-yan HUChang-wen InstituteforChemicalPhysics DepartmentofChemistryBeijingInstituteofTechnologyBeijing100081P.R.China InstituteforChemicalPhysics DepartmentofChemistryBeijingInstituteofTechnologyBeijing100081P.R.China／／ChemistryDepartmentAnhuiNormalUniversityWuhu241000P.R.China

Via layer-by-layer assembly, the polyoxometalates of Keggin type, SiW_ 11O_ 39Ni(H_2O) 6-(SiNiW_ 11) and {SiW_ 11O_ 39Mn(H_2O) 6-}(SiMnW_ 11) were first immobilized on a 4-aminothiophenol(4-ATP) modified glassy carbon electrode surface. The electrochemical behavior of these polyoxometalates was investigated. They exhibited some special properties in the films, which are different from those in a homogeneous aqueous solution. Their reaction mechanism in a multilayer film is proposed. The electrocatalytic behavior of these multilayer film electrodes for the reduction of BrO-_3 and NO-_2 were comparatively studied.

关键词： Polyoxometalate layer-by-layer assembly Electrochemical behavior Electrocatalytic reduction BrO_3^- NO_2^-

Solvothermal Syntheses and Crystal Structures of Two New Nonmetal Borates:C_4H_(10)N_2·B_6O_8(OH)_2 and (NH_3CH_2CH_2NH_3)B_5O_8(OH)

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Chinese Journal of Structural Chemistry 2007年第3期26卷 257-262页

作者： lü gui-qin YANG Xin lI Min SHI Heng-Zhen School of Science Beijing Institute of Technology Beijing 100081 China Institute of Applied Catalysis Yantai University Yantai 264005 China Department of Chemistry Zhoukou Normal University Zhoukou 46600 1 China

Two new borate compounds, C4H10N2·B6O8（OH）2 and （NH3CH2CH2NH3）B5O8 （OH）2, have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermal analysis. Compound 1 crystallizes in the monoclinic system, space group P21/c, with a = 8.3318（17）, b = 6.2118（12）, c = 12.479（3） A, β = 108.96（3）°, V = 610.8（2） A^3, Mr = 313.02, Z = 2, 13,.= 1.702 g/cm^,/J = 0.150 mm^-1, F（000） = 320, R = 0.0387 and wR = 0.0924. Its layered structure is linked by infinite covalently coordinated neutral sheets with 3,20-membered window system, which are built up from alternative B6O8（OH）2 subunits donated by two piperzazine nitrogen donors. 2 crystallizes in monoclinic, space group Co, with a = 6.7207（13）, b = 11.481 （2）, c = 12.564（3）A,β = 95.25（3）°, V = 965.4（3） A^3, Mr = 261.18, Z = 4, Dc = 1.797 g/cm^3,/t = 0.164 mm^-1, F（000） = 536, R = 0.0396 and wR = 0.0752. Its oxoborate structure is generated from the sheets of 3,9-membered boron rings bonded diamine molecules through electrostatic and H-bonding interactions to form a two-dimensional layered network.

关键词： solvothermal synthesis crystal structure borate

Enhanced Sensing Mechanism Based on Shifting an Exceptional Point

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Research 2024年第3期6卷 285-292页

作者： Xuan Mao Guo-qing qin Hao Zhang Bo-Yang Wang Dan long gui-qin li gui-lu long Department of Physics State Key Laboratory of Low-Dimensional Quantum PhysicsTsinghua UniversityBeijing 100084China Beijing Institute of Radio Measurement The Second Academy of China Aerospace Science and Industry Corporation(CASIC)Beijing 100854China Purple Mountain laboratories Nanjing 21111China Frontier Science Center for Quantum Information Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Non-Hermitian systems associated with exceptional points (EPs) are expected to demonstrate a giant response enhancement for various sensors. The widely investigated enhancement mechanism based on diverging from an EP should destroy the EP and further limits its applications for multiple sensing scenarios in a time sequence. To break the above limit, here, we proposed a new enhanced sensing mechanism based on shifting an EP. Different from the mechanism of diverging from an EP, our scheme is an EP nondemolition and the giant enhancement of response is acquired by a slight shift of the EP along the parameter axis induced by perturbation. The new sensing mechanism can promise the most effective response enhancement for all sensors in the case of multiple sensing in a time sequence. To verify our sensing mechanism, we construct a mass sensor and a gyroscope with concrete physical implementations. Our work will deepen the understanding of EP-based sensing and inspire designing various high-sensitivity sensors in different physical systems.

关键词： mechanism shifting exceptional

镍取代Dawson型多酸多层膜电极的修饰及循环伏安测试

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北京理工大学学报 2006年第7期26卷 639-642页

作者：吕桂琴韩磊北京理工大学理学院北京100081

利用电化学生长法在玻碳电极上制备了含取代Dawson型磷钨杂多酸K8P2W17O61(NiOH2)多层膜修饰电极,通过循环伏安法控制制备和检测多层膜的沉积过程,并对其电化学过程进行系统研究实验表明,在酸性缓冲溶液中,多层膜的循环伏安图中出现3对... 详细信息

利用电化学生长法在玻碳电极上制备了含取代Dawson型磷钨杂多酸K8P2W17O61(NiOH2)多层膜修饰电极,通过循环伏安法控制制备和检测多层膜的沉积过程,并对其电化学过程进行系统研究实验表明,在酸性缓冲溶液中,多层膜的循环伏安图中出现3对单电子氧化-还原峰,峰电流和扫描速率的平方根成正比,表明电极过程的控制步骤是扩散过程.该多层膜修饰电极可催化BrO3-和NO2-的电化学还原过程.

关键词：取代Dawson型磷钨杂多酸(P2W17Ni) 修饰电极循环伏安

计时电量法测定4,5-二氮芴-9-酮的扩散系数和反应速率常数

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北京理工大学学报 2014年第6期34卷 650-654页

作者：吕桂琴马淑贤北京理工大学化学学院北京100081

运用循环伏安法测定4,5-二氮芴-9-酮(DAFO)在DMF溶液中不同扫描速率时的循环伏安图,出现2对峰形良好的氧化还原峰;采用计时电量法通过控制阶跃电位,测得不同温度下DAFO在DMF溶液中的扩散系数和反应速率常数,293 K时扩散系数为5.39×10^(... 详细信息

运用循环伏安法测定4,5-二氮芴-9-酮(DAFO)在DMF溶液中不同扫描速率时的循环伏安图,出现2对峰形良好的氧化还原峰;采用计时电量法通过控制阶跃电位,测得不同温度下DAFO在DMF溶液中的扩散系数和反应速率常数,293 K时扩散系数为5.39×10^(—6)cm^2·s^(—1);当选择阶跃电位使电极过程处于扩散和电化学混合控制时,测得不同电位的反应速率常数κ_f.根据不同温度下的标准速率常数κ_0,得到表观活化能E_a为10.5 kJ·mol^(—1).

关键词： 4,5-二氮芴-9-酮循环伏安计时电量扩散系数反应速率常数

金属卟啉与Keggin型硅钨酸修饰电极的制备及电催化性能测定

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无机化学学报 2011年第9期27卷 1705-1708页

作者：罗贤吕桂琴北京理工大学理学院化学系北京100081

运用自组装和电化学组装联用方法,将镍卟啉配合物THPPNi和Keggin型硅钨酸SiW12修饰到玻碳电极上,制备镍卟啉修饰电极和镍卟啉/硅钨酸复合修饰电极,研究其在DMF溶液中的电化学行为,测定在碱性条件下对NO2-和BrO3-的电催化性能。循环伏安... 详细信息

运用自组装和电化学组装联用方法,将镍卟啉配合物THPPNi和Keggin型硅钨酸SiW12修饰到玻碳电极上,制备镍卟啉修饰电极和镍卟啉/硅钨酸复合修饰电极,研究其在DMF溶液中的电化学行为,测定在碱性条件下对NO2-和BrO3-的电催化性能。循环伏安和交流阻抗研究结果表明,复合修饰电极THPPNi/SiW12的电极过程属于扩散控制过程;复合修饰电极优于单一修饰金属卟啉和多酸修饰电极。

关键词：卟啉硅钨酸修饰电极循环伏安交流阻抗

纳米Pt/Graphene复合电极的制备及对甲醇电催化性能的影响

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北京理工大学学报 2016年第6期36卷 656-660页

作者：吕桂琴穆雪梅北京理工大学化学学院北京100081

采用一步还原法制备直接甲醇燃料电池纳米Pt/graphene(Pt/G)阳极.XRD和SEM表征表明Pt纳米均匀分散于石墨烯表面.循环伏安和计时电流的电化学测定结果表明:复合纳米Pt/G的催化活性和稳定性优于纯铂;采用计时电量法测定298K时甲醇在硫酸... 详细信息

采用一步还原法制备直接甲醇燃料电池纳米Pt/graphene(Pt/G)阳极.XRD和SEM表征表明Pt纳米均匀分散于石墨烯表面.循环伏安和计时电流的电化学测定结果表明:复合纳米Pt/G的催化活性和稳定性优于纯铂;采用计时电量法测定298K时甲醇在硫酸溶液中扩散系数为1.37×10^(-9) cm^2·s^(-1),以及在不同阶跃电位下甲醇催化氧化反应速率常数kf.

关键词： Pt/graphene 甲醇氧化循环伏安法计时电量法

Potential Benefits of Green Tea in Prostate Cancer Prevention and Treatment: A Comprehensive Review

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Chinese Journal of Integrative Medicine 2024年第11期30卷 1045-1055页

作者： lIU gui-hong YAO Ze-qin CHEN Guo-qiang lI Ya-lang lIANG Bing Department of Urology Sanya Central Hospital (The Third People's Hospital of Hainan Province) Department of Urology Yuzhou People's Hospital

Prostate cancer is a prevalent and debilitating disease that necessitates effective prevention and treatment strategies. Green tea, a well-known beverage derived from the Camellia sinensis plant, contains bioactive compounds with potential health benefits, including catechins and polyphenols. This comprehensive review aims to explore the potential benefits of green tea in prostate cancer prevention and treatment by examining existing literature. Green tea possesses antioxidant, anti-inflammatory, and anti-carcinogenic properties attributed to its catechins, particularly epigallocatechin gallate. Epidemiological studies have reported an inverse association between green tea consumption and prostate cancer risk, with potential protection against aggressive forms of the disease. laboratory studies demonstrate that green tea components inhibit tumor growth, induce apoptosis, and modulate signaling pathways critical to prostate cancer development and progression. Clinical trials and human studies further support the potential benefits of green tea. Green tea consumption has been found to be associated with a reduction in prostate-specific antigen levels, tumor markers, and played a potential role in slowing disease progression. However, challenges remain, including optimal dosage determination, formulation standardization, and conducting large-scale, long-term clinical trials. The review suggests future research should focus on combinatorial approaches with conventional therapies and personalized medicine strategies to identify patient subgroups most likely to benefit from green tea interventions.

关键词： epigallocatechin gallate green tea prevention prostate cancer review treatment

一步法制备纳米铂/石墨烯及电催化甲醇的交流阻抗和扩散系数测定

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无机化学学报 2016年第7期32卷 1170-1176页

作者：刘文超吕桂琴北京理工大学化学学院北京100081

采用绿色还原剂抗坏血酸,一步法制备纳米铂/石墨烯。对其进行X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)形貌结构表征,铂纳米粒子均匀分散于纳米石墨烯片层褶皱间,有效减少了团聚现象。运用循环伏安法(CV)和计时电流法(... 详细信息

采用绿色还原剂抗坏血酸,一步法制备纳米铂/石墨烯。对其进行X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)形貌结构表征,铂纳米粒子均匀分散于纳米石墨烯片层褶皱间,有效减少了团聚现象。运用循环伏安法(CV)和计时电流法(CA)研究纳米铂/石墨烯对甲醇电催化氧化活性和稳定性,通过交流阻抗(EIS)定量测定,发现铂/石墨烯比铂具有更优异的电荷传输性能,电荷转移阻抗下降了34.8%。计时电量法(CC)测定得到甲醇在铂/石墨烯电极的表面扩散系数为1.42×10^(-9) cm^2·s^(-1)。与铂纳米粒子相比,纳米铂/石墨烯对甲醇电催化氧化具有更高的活性和稳定性,显著提高电极催化活性表面积和电荷传输及转移性能。

关键词：铂/石墨烯电催化交流阻抗计时电量

Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves

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China Ocean Engineering 2024年第1期38卷 81-92页

作者： lIAO Xi-yu XIA Jin-song CHEN Zhan-yang TANG qin ZHAO Nan ZHAO Wei-dong gui Hong-bin Marine Design&Research Institute of China Shanghai 200011China Ship Structure Division China Ship Scientific Research CenterWuxi 214082China College of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China State Key laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China School of Foreign Studies Jiangnan UniversityWuxi 214122China

To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be ***,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step *** on the wave elevation of uni-and bi-directional waves is also carried *** a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,***,the differences in structural response characteristics of trimaran in different wave fields are *** results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.

关键词： CFD-FEA fluid-structure coupling structural responses trimaran bi-directional cross sea