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Absolute Orientation of Molecules with Competing Hydrophilic Head Groups at the Air/Water Interface Probed with Sum Frequency Generation Vibrational Spectroscopy

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Chinese Journal of Chemical Physics 2009年第2期22卷 197-203页

作者： feng Wang zhi Huang zhi-feng cui Hong-fei Wang Department of Physics Anhui Normal University Wuhu 241000 China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

The constructive or destructive spectral interference between the molecular groups oriented up and down at the interface in the sum-frequency generation （SFG） spectra provides a direct measurement of the absolute orientation of these molecular groups. This simple approach can be employed to interrogate absolute molecular orientations other than using the complex absolute phase measurement in the SFG studies. We used the -CN group in the p-cyanophenol （PCP） molecule as the internal phase standard, and we measured the phases of the SFG fields of the -CN groups in the 3,5-dimethyl-4-hydroxy-benzonitrile （35DMHBN） and 2,6-dimethyl-4-hydroxy-benzonitrile （26DMHBN） at the air/water interface by measuring the SFG spectra of the aqueous surfaces of the mixtures of the PCP, 35DMHBN, and 26DMHBN solutions. The results showed that the 35DMHBN had its -CN group pointing into the aqueous phase; while the 26DMHBN, similar to the PCP, had its -CN group pointing away from the aqueous phase. The tilt angles of the -CN group for both the 35DMHBN and 26DMHBN molecules at the air/water interface were around 25°-45° from the interface normal. These results provided insights on the understanding of the detailed balance of the competing factors, such as solvation of the polar head groups, hydrogen bonding and hydrophobic effects, etc., on influencing the absolute molecular orientation at the air/water interface.

关键词： Sum frequency generation vibrational spectroscopy Air/water interface Molecule orientation p-cyanophenol

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Temperature and electron density of soil plasma generated by LA-FPDPS

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Frontiers of physics 2012年第6期7卷 721-727页

作者： Xia-Fen Li Wei-Dong Zhou zhi-feng cui The Institute of Information Optics Zhejiang Normal UniversityJinhua 321004China Department of Physics Anhui Normal UniversityWuhu 241000China

Electron temperature and electron number density are important parameters in the characterization of plasma. In this paper the electron temperature and electron number density of soil plasma generated by laser ablation combined with nanosecond discharge spark at different discharge voltages have been studied. Saha-Boltzmann plot and Stark broadening are used to determine the temper- ature and electron number density. It is proved that local thermal equilibrium is fulfilled in the nanosecond spark enhanced plasma. The enhanced optical emission, signal to noise ratio and the stability in term of the relative standard deviation of signal intensity at different spark voltages were investigated in detail. A relative stable discharge process was observed with use of a 10 kV discharge voltage under the carried experimental configuration.

关键词： laser ablation fast pulse discharge plasma spectroscopy (LA-FPDPS) local thermodynamic equilibrium (LTE) electron temperature electron number density discharge voltage

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Quantitative Interpretation of Polarization SFG Vibrational Spectra of Air/Methanol Interface

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Chinese Journal of Chemical Physics 2006年第3期19卷 187-189页

作者： Hui Wu Wen-kai Zhang Wei Gan zhi-feng cui Hong-fei Wang Department of Physics Anhui Normal University Wuhu 241000 China State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100080China

Even though in IR and Raman spectra of liquid methanol there is always an apparent feature for the asymmetric stretching mode of the CH3 group around 2970 cm^-1, this feature has not been observed in the Sum Frequency Generation Vibrational Spectroscopy （SFG-VS） in any polarizations from the air/methanol interface. Here we present a treatment based on a corrected bond additivity model to quantitatively interpret the SFG-VS of the air/methanol interface from the IR and Raman spectra of liquid methanol.

关键词： Sum frequency generation Bond additivity model Raman polarizability

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Experimental and Theoretical Study on p-Chlorofluorobenzene in the S0,S1 and D0 States

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Chinese Journal of Chemical Physics 2020年第4期33卷 401-410,I0001页

作者： Jia-nan Fan Ting-ting cui Zheng-bo Qin Xian-feng Zheng zhi-feng cui Anhui Province Key Laboratory of Optoelectric Materials Science and Technology Department of PhysicsAnhui Normal UniversityWuhu 241000China

The geometric structures and vibration frequencies of para-chlorofluorobenzene(p-Cl FPh)in the first excited state of neutral and ground state of cation were investigated by resonanceenhanced multiphoton ionization and slow electron velocity-map *** infrared spectrum of S0 state and absorption spectrum for S1←S0 transition in p-Cl FPh were also *** on the one-color resonant two-photon ionization spectrum and two-color resonant two-photon ionization spectrum,we obtained the adiabatic excited-state energy of p-Cl FPh as 36302±4 cm^-*** the two-color resonant two-photon ionization slow electron velocity-map imagin spectra,the accurate adiabatic ionization potential of p-Cl FPh was extrapolated as 72937±8 cm^-1 via threshold ionization *** addition,FranckCondon simulation was performed to help us confidently ascertain the main vibrational modes in the S1 and D0 ***,the mixing of vibrational modes between S0→S1 and S1→D0 has been analyzed.

关键词： Resonance-enhanced multiphoton ionization Slow electron velocity-map imaging Duschinsky mixing para-Chlorofluorobenzene

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Measurement of Photoionization Cross Sections of the Excited States of Titanium

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Chinese Journal of Chemical Physics 2009年第6期22卷 615-620,J0002页

作者： Jia-jun Yang Xing-yong Hu Hong-xia Wu Jian-mei Fan Ran Cong Yi Cheng Xue-han Ji Guan-xin Yao Xian-feng Zheng zhi-feng cui Institute of Atomic and Molecular Physics Anhui Normal University Wuhu 242000 China

Resonance-enhanced multiphoton ionization of the titanium atoms has been investigated in the 293 321 nm wavelength. We couple a laser-ablated metal target into a molecular beam to produce free atoms. Ions produced from photoionization of the neutral atoms are monitored by a home-built time-of-flight mass spectrometer. Photoionization cross sections of the excited states of Ti I were deduced from the dependence of the ion signal intensity on the laser intensity for photon energies close to the ionization threshold. The values obtained range from 0.2 Mb to 6.0 Mb. No significant isotope-dependence was found from measurements of the photoionization cross sections of ^46Ti, ^47Ti, and ^48Ti.

关键词： Photoionization cross section Excited state Titanium

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TR-ESR Investigation on Reaction of Vitamin C with Excited Triplet of 9,10-phenanthrenequinone in Reversed Micelle Solutions

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Chinese Journal of Chemical Physics 2011年第2期24卷 150-154,I0003页

作者：许新胜史蕾刘毅季学韩崔执凤安徽师范大学原子与分子物理研究所芜湖241000

Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C （VC） and the triplet excited states of 9,10-phenanthrenequinone （PAQ） in ethylene glycol-water （EG-H2O） homogeneous and inhomogeneous reversed micelle solutions. Reversed micelle solutions were used to be the models of physiological environment of biological cell and tissue. In PAQ/EG-H2O homogeneous solution, the excited triplet of PAQ （3PAQ＊） abstracts hydrogen atom from solvent EG. In PAQ/VC/EG-H2O solution, 3pAQ＊ abstracts hydrogen atom not only from solvent EG but also from VC. The quenching rate constant of 3pAQ＊ by VC is close to the diffusion-controlled value of 1.41 × 108 L/（mol.s）. In hexadecyltrimethylammonium bromide （CTAB）/EG-H2O and aerosol OT （AOT）/EG- H2O reversed micelle solutions, 3pAQ＊ and VC react around the water-oil interface of the reversed micelle. Exit of 3pAQ＊ from the lipid phase slows down the quenching reaction. For Triton X-100 （TX-100）/EG-H2O reversed micelle solution, PAQ and VC coexist inside the hydrophilic polyethylene glycol core, and the quenching rate constant of 3pAQ＊ by VC is larger than those in AOT/EG-H2O and CTAB/EG-H2O reversed micelle solutions, even a little larger than that in EG-H2O homogeneous solution. The strong emissive chemically induced dynamic electron polarization of As＇- resulted from the effective TM spin polarization transfer in hydrogen abstraction of 3pAQ＊ from VC.

关键词： 9,10-phenanthrenequinone Vitamin C Time-resolved electron spin resonance Reversed micelle

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2-苯亚胺官能化吲哚基铕胺基配合物与芳基取代甲脒的反应性（英文）

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无机化学学报 2017年第1期33卷 169-174页

作者：冯志君崔巧玉韦芸周双六吴运军王少印皖南医学院医用基础化学教研室芜湖241002 功能分子固体教育部重点实验室安徽师范大学化学与材料科学学院分子材料实验室芜湖241000

2-(苯亚胺基次甲基)吲哚铕胺基配合物[η1∶η1-2-(C6H5NH=CH)C8H5N]2Eu[N(Si Me3)2](1)与二芳基取代甲脒(2,6-R2C6H3N=CHNH(C6H3R2-2,6)(R=iPr(2),Me(3))经过配体交换反应,分别得到了含吲哚基脒基铕配合物[η1∶η1-2-(C6H5NH=CH)C8H5N]Eu[(η3-2,6-iPr2C6H3)N=CHN(C6H3iPr2-2,6)][N(Si Me3)2](4)和含脒基的稀土铕配合物[(η3-2,6-Me2C6H3)N=CHN(C6H3Me2-2,6)]2Eu[N(Si Me3)2](5)。结果表明,脒基的位阻显著影响了吲哚基稀土金属胺基配合物与二芳基取代甲脒的配体交换反应。配合物4和5通过IR、元素分析和X射线单晶衍射分析进行了表征。

关键词：稀土金属铕吲哚基配体胺基配合物

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大菱鲆(Scophthalmus maximus)快速生长品系和高成活率选育品系的配合力分析

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海洋与湖沼 2017年第5期48卷 1100-1107页

作者：马爱军王新安黄智慧孙志宾刘志峰崔文晓曲江波中国水产科学研究院黄海水产研究所农业部海洋渔业可持续发展重点实验室青岛市海水鱼类种子工程与生物技术重点实验室青岛266071 青岛海洋科学与技术国家实验室海洋生物学与生物技术功能实验室青岛266071 烟台开发区天源水产有限公司烟台264003

利用人工授精技术,通过不完全双列杂交交配设计,以大菱鲆2个配套选育系进行双列杂交产生的数据为分析对象,利用统计学和数量遗传学方法对体质量和存活性状进行了一般配合力和特殊配合力测定以及杂交优势分析。结果表明,综合分析50个杂... 详细信息

利用人工授精技术,通过不完全双列杂交交配设计,以大菱鲆2个配套选育系进行双列杂交产生的数据为分析对象,利用统计学和数量遗传学方法对体质量和存活性状进行了一般配合力和特殊配合力测定以及杂交优势分析。结果表明,综合分析50个杂交组合在不同月龄的特殊配合力和亲本的一般配合力以及杂种优势率发现,FG1♀×HS1♂组合为最佳杂交组合。在6月龄、9月龄、12月龄和15月龄,FG1♀×HS1♂组合的体重分别为49.4010g、162.8510g、311.0716g和619.8467g,比相应发育阶段的普通商品苗种依次提高了31.36%、44.46%、50.55%和69.06%;在3—6、6—9、9—12和12—15月龄,FG1♀×HS1♂组合的成活率分别为96.4%、98.9%、99.2%和99.0%,比相应发育阶段的普通商品苗种分别提高了37.62%、27.55%、11.45%和6.35%,显示出良好的生长性能。最佳系间杂交组合FG1♀×HS1♂的确定,为选育出优质、高产的大菱鲆新品种提供了理论依据。

关键词：大菱鲆快速生长品系高成活率品系配合力

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Mitophagy is induced by PTEN-induced kinase 1 gene silencing in dopaminergic neurons

Mitophagy is induced by PTEN-induced kinase 1 gene silencing...

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中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： zhi-feng Qi,Tao cui,Li LV,Hua GAO,Hui YANG~* Beijing Institute for Neuroscience,Capital Medical University,Beijing Center for Neural Regeneration & Repair,Key Laboratory for Neurodegenerative Disease of the Ministry of Education,Beijing 100069,China

＜正＞Parkinson’s disease is a common neurodegenerative *** studies indicate that the abnormal autophagy in neurons is the main reason for the generation of ***1（PTEN-induced kinase 1） is one of PD-related genes, which is directly involved in the 1 function of ***,it is not clear that autophagy could be activated by mitochondrial injury induced by PINK1 gene *** study showed that silencing PINK1 may induce autophagy in dopaminegic cell line（MN9D）.We found that the level of LC3II（vacuole membrane associate type）,which has been accepted as marker of autophagy,increased significantly at 48h since PINK1 silencing by Western *** number of vacuoles with mitochondria,which are enclosed by double membrane（mitophagy） was also observed to increase in the group of PINK1 RNA *** of monodansylcadaverine（MDC） and acidotropic orange staining also showed that the level of autophagy was induced significantly by PINK1 gene ***,the level of Beclinl and phosphorylation of Bcl2（p-Bcl2） were increased and the generation of reactive oxygen species（ROS） was also elevated when silencing PINK1 gene in *** conclusion,our study suggests that PINK1 gene silencing may increase the ROS generation and induce mitophagy by activating Beclinl and p-Bcl2 and may provide a clue to find new drugs for the treatment of PD in clinic.

关键词： PINK1 mitophagy Bcl-2 RNA interference Parkinson’s disease.

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伪步甲危害遥感监测及地形分析——以新疆玛纳斯-呼图壁县草场为例

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干旱区研究 2017年第2期34卷 437-444页

作者：吴秀兰郑江华李帅冯志敏崔宇曹孟磊新疆维吾尔自治区气候中心新疆乌鲁木齐830002 新疆大学资源与环境科学学院新疆乌鲁木齐830046

为揭示伪步甲灾害在不同地形梯度上的差异,结合RS与GIS,于2013—2014年对新疆玛纳斯-呼图壁县草场伪步甲灾害发生情况进行了遥感监测,将危害情况分成不同类别,并分别统计2 a间伪步甲危害面积的变化情况。在此基础上,利用数字高程模型(D... 详细信息

为揭示伪步甲灾害在不同地形梯度上的差异,结合RS与GIS,于2013—2014年对新疆玛纳斯-呼图壁县草场伪步甲灾害发生情况进行了遥感监测,将危害情况分成不同类别,并分别统计2 a间伪步甲危害面积的变化情况。在此基础上,利用数字高程模型(DEM)提取高程、坡度及坡向因子,分别与不同的伪步甲危害类型进行空间叠加统计分析,探讨研究区伪步甲灾害地形梯度特征。结果表明:900~1 200 m高程范围是伪步甲灾害的高发区;伪步甲危害区主要发生在0°~8.8°区间内;坡向梯度上,严重危害区并没有表现出明显的分布规律。

关键词：伪步甲(Prosodes dilaticollis) 草场灾害遥感监测地形梯度玛纳斯-呼图壁新疆

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