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Solvent Effect on the Photoinduced Electron Transfer Reaction Between Thioxanthen-9-one and Diphenylamine

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Chinese Journal of Chemical physics 2015年第4期28卷 -页

作者： Lin Chen Qiao-hui Zhou Xiang Liu Xiao-guo Zhou Shi-lin Liu Hefei National laboratory for Physical Sciences at the Microscale and department of Chemical physics University of Science and Technology of ChinaHefei 230026 China

Photoinduced chemical reaction between thioxanthen-9-one (TX) and diphenylamine (DPA) were investigated by the nanosecond laser flash photolysis. With photolysis at 355 nm, the triplet TX (3TX*) is produced via a Franck-Condon excitation and intersystem crossing. In the transient absorption spectra of the reduction of 3TX* by DPA in pure and aqueous CH3CN, four bands are clearly observed and assigned to absorption of 3TX*, TXH·, TX·? and DPA·+, respectively. With the increase of solvent polarity, the blue-shift was observed for all absorption bands of the intermediates. With the aid of dynamic decay curves, an electron transfer followed by a protonation process is confirmed for the reduction of 3TX* by DPA. The quenching rate constants of 3TX* by DPA very slightly decrease from 9.7×109 L/(mol·s) in pure CH3CN, to 8.7×109 L/(mol·s) in CH3CN:H2O (9:1), 8.0×109 L/(mol·s) in CH3CN:H2O (4:1) and 7.5×109 L/(mol·s) in CH3CN:H2O (1:1). Therefore water plays a minor role in the title reaction, and moreover no obvious medium effect of solvent polarity is observed for the electron transfer between 3TX* and DPA, indicating that the 3nπ* and 3ππ* states of TX have the approximate ability to attract an electron from DPA.

关键词： Electron transfer Protonation Reaction mechanism Absorption spectra laser flash photolysis

Upper-and Lower-tropospheric Circulation Anomalies Associated with Interannual Variation of Pakistan Rainfall during Summer

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Advances in Atmospheric Sciences 2020年第11期37卷 1179-1190页

作者： Riyu LU Saadia HINA Xiaowei HONG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China key laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China department of Environmental Sciences and Engineering Government College UniversityFaisalabad 38000Pakistan Climate Change Research Center(CCRC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of the Chinese Academy of SciencesBeijing 100049China

This study investigated the large-scale circulation anomalies,in both the upper and lower troposphere,associated with the interannual variation of rainfall in Pakistan during summer,using the station observation data in this country and circulation data of the NCEP−NCAR reanalysis from 1981 to *** showed that the upper-and lower-tropospheric circulation anomalies associated with monthly rainfall variability exhibit similar features from June to August,so analyses were performed on June−August circulation and Pakistan rainfall *** analyzed results indicated that summer rainfall in Pakistan is enhanced when there is an anticyclonic anomaly to the northwest of Pakistan in the upper troposphere and easterly anomalies along the southern foothills of the Himalayas in the lower troposphere,and vice *** upper-and lower-tropospheric circulation anomalies were found to be related,but show unique *** upper-tropospheric anticyclonic anomaly is closely related to the Silk Road Pattern along the Asian westerly jet,while the lower-tropospheric easterly anomalies are related to the cyclonic anomaly to the south of Pakistan,i.e.,intensified South Asian monsoon *** results presented here suggest that the interannual variability of summer rainfall in Pakistan is a combined result of upper-and lower-tropospheric circulation anomalies,and of extratropical and tropical circulation anomalies.

关键词： rainfall Pakistan interannual variability Silk Road Pattern monsoon trough

Large electrical strain in lead-free K_(0.5)Na_(0.5)NbO_(3)-based ceramics by heterovalent doping

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Journal of Materiomics 2023年第5期9卷 959-970页

作者： Xiangjian Wang Jun Wang Wenping Geng Guohua Dong Brahim Dkhil Xiaojie Lou department of Information Engineering Quzhou College of TechnologyQuzhou324000China Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an710049China Science and Technology on Electronic Test and Measurement laboratory North University of ChinaTaiyuan030051China Electronic Materials Research laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchXi'an Jiaotong UniversityXi'an710049China Applied physics Division of Materials ScienceDepartment of Engineering Sciences and MathematicsLuleåUniversity of TechnologySE-97187LuleåSweden Laboratoire Structures Proprietes et Modelisation des SolidesUniversite Paris SaclayCentraleSupelecCNRS-UMR8580Grande Voie des VignesCh^atenay MalabryCedex92295France

Heterovalent doped(K_(0.48-0.07)xNa_(0.52-0.43)xBi_(0.5)x)(Nb_(0.95-0.95x)Sb_(0.05-0.05x)Zrx)O_(3)ceramics were fabricated using conventional solid-state ***,the phase structures,dielectric,ferroelectric,and electricstrain properties were *** compositions were tuned to be located at polymorphic phase boundary with increasing heterovalent Bi3t and Zr4t doping levels.A large strain of 0.19%was obtained at relatively low electric fields of 30 kV/cm in the composition of x=*** normalized large-signal d33*values were approximately 633 pm/V under a low driving electric field of 30 kV/cm,which were comparable or larger than the values reported for other lead-free *** large strains obtained can be attributed to the formation of nanodomains and high-density domain walls,which were confirmed by the observations of domain morphology using transmission electron microscopy(TEM)*** temperature stability of the strain properties of the x=0.04 sample could be ascribed to the sluggish behaviour for the local structural heterogeneity in heterovalent-ion doped KNN *** simulations revealed that the Zr^(4t)produce the local stress at the BO6 octahedra and Bi3t could yield off-centering of AO12 ployhedron due to the nature of Bi 6s lone pair electrons,which induced lattice expansion and local distortions in the *** local displacements are strongly anisotropic in heterovalent-ion doped *** is believed that random local fields exist in these compositions owing to the eixstence of charge *** heterovalent doping of Bi^(3t)and Zr^(4t)could destory simultaneously the orthorhombic symmetry and the short-range ferroelecctric order,leading to the formation of complex nanodomains and local structral *** doping may,therefore,offer a new avenve to design novel K0.5Na0.5NbO3(KNN)-based materials for their mutifunctional applications.

关键词： Lead-free Strain Heterovalent doping Local structure Nanodomain

Collimated gamma beams with high peak flux driven by laser-accelerated electrons

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High Power laser Science and Engineering 2023年第2期11卷 88-93页

作者： Lulin Fan Tongjun Xu Shun Li Zhangli Xu Jiancai Xu Jianqiang Zhu Baifei Shen Liangliang Ji State key laboratory of High Field laser physics and CAS Center for Excellence in Ultra-intense laser Science Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina department of physics Shanghai Normal UniversityShanghaiChina

laser-accelerated electrons are promising in producing gamma-photon beams of high peak flux for the study of nuclear photonics,obtaining copious positrons and exploring photon–photon interaction in *** report on the experimental generation of brilliant gamma-ray beams with not only high photon yield but also low divergence,based on picosecond laser-accelerated *** 120 J 1 ps laser pulse drives self-modulated wakefield acceleration in a high-density gas jet and generates tens-of-MeV electrons with 26 nC and divergence as small as 1.51◦.These collimated electrons produce gamma-ray photons through bremsstrahlung radiation when transversing a high-Z solid *** design a high-energy-resolution Compton-scattering spectrometer and find that a total photon number of 2.2×10^(9)is captured within an acceptance angle of 1.1°for photon energies up to 16 *** between the experimental results and Monte Carlo simulations illustrates that the photon beam inherits the small divergence from electrons,corresponding to a total photon number of 2.2×10^(11)and a divergence of 7.73°.

关键词： bremsstrahlung Compton scattering gamma-ray beam laser-electron acceleration spectrometer

Differential cross sections and oscillator strengths in electron energy loss spectrum of b^1П_u electronic state of N_2

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Science China Mathematics 1995年第3期38卷 368-375页

作者：徐克尊钟志萍武淑兰凤任飞 S.Ohtani T.Takayanagi A.Kimota department of Modern physics University of Science and Technology of China Hefei 230027 China Institute for laser Science University of Electro-Communication Tokyo 182 Japan

The energy loss spectrum of the molecular nitrogen in the energy region 12 -14 eV has been measured at 300 eV impact energy and in the range of scattering angles of 2.75℃- 10.25℃. The differential cross sections and generalized oscillator strengths have been determined for individual vibronic excitation band (v’ = 1 - 4) of b1Пu from the ground state of N2 and the absolute optical oscillator strengths have also been obtained by taking the limit of K→ 0. Results have been compared with experimental data and theoretical calculations previously published.

关键词： optical oscillator strength differential cross sections generalized oscillator strength Frank-Condon factor.

Highly active cobalt-doped nickel sulfide porous nanocones for high-performance quasi-solid-state zinc-ion batteries

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Journal of Energy Chemistry 2022年第3期31卷 237-249,I0008页

作者： Xin Tong Yun Li Ning Pang Yang Zhou Dajun Wu Dayuan Xiong Shaohui Xu Lianwei Wang Paul K.Chu key laboratory of Polar Materials and Devices(MOE) Department of ElectronicsEast China Normal UniversityShanghai 200241China Jiangsu laboratory of Advanced Functional Materials School of Electronic and Information EngineeringChangshu Institute of TechnologyChangshu 215500JiangsuChina School of physics and Electronic Engineering Hanshan Normal UniversityChaozhou 521041GuangdongChina department of physics Department of Materials Science and Engineeringand Department of Biomedical EngineeringCity University of Hong KongKowloon 999077Hong KongChina

Flexible quasi-solid zinc-ion batteries(ZIBs)have large potential in power applications due to the low price,wearable nature,safety,and high ***,the use of transition metal sulfide cathodes in ZIBs has not been studied extensively and the underlying mechanism and theoretical basis of this type of batteries are not well ***,a highly active cobalt-doped Ni_(3)S_(2) porous nanocone framework(C12NS)is designed and demonstrated as a zinc-ion battery ***-principles calculation and experiments reveal that the cobalt dopant improves the battery properties *** assembled flexible zinc-ion battery exhibits a high specific capacity of 453.3 mAh g^(−1)at a current density of 0.4 A g^(−1)in as well as excellent cycling stability as manifested by a capacity retention ratio of 89.5%at a current density of 4 A g^(−1)after 5000 *** peak energy density of 553.9 Wh kg^(−1)is also superior to those of most recently reported NiCo-based zinc-ion *** importantly,the flexible battery can be operated under severe mechanical bending and even continues to work after physical puncturing without showing *** exciting results not only reveal a novel design of cathode materials for zinc-based batteries,but also suggest their immense commercial potential in portable and wearable electronics.

关键词： Zn-ion battery Quasi-solid electrolyte Nanocone Doping Wearable electronic

Hemiphasmid Side-Chain Liquid Crystalline Polynorbornene: Phase Structure and Strain-Hardening Based on “Multi-Chain Column” Physical Crosslinks

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Hemiphasmid Side-Chain Liquid Crystalline Polynorbornene: Ph...

HPLC separation of higher fullerenes in the synthetical "graphite smokes" soot

2016年两岸三地高分子液晶态与超分子有序结构学术研讨会（暨第十四届全国高分子液晶态与超分子有序结构学术论文报告会）

作者： Ruiying Zhao Shuang Yang Er-qiang Chen Beijing National laboratory for Molecular Sciences Department of Polymer Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular Engineering Peking University

Hemiphasmid mesogen is composed of two parts with different shapes,a rod-like and a fan-like moieties that are linked together.1 Due to the special shape matching mechanism,side-chain liquid crystalline polymers(SCLCPs)with side groups containing hemiphasmid mesogens have fantastic ability of *** diversity of side groups provides abundant manners for designing ordered

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Chinese Journal Of Geochemistry 2012年第3期31卷 303-308页

作者： ZHANG Jun Luann Becker LIANGHandong LUO Yang XU Wei WANG Hongcui Water Environmental Monitoring Center Haihe River Water Conservancy CommissionMinistry of Water ResourcesTianjin 300170China department of physics and Astronomy Johns Hopkins UniversityBaltimoreMD 21218USA State key laboratory of Coal Resources and Safety Mining China University of Mining and TechnologyBeijing 100083China

Higher fullerenes(C84,C90,C92,C94 and C96) were successfully isolated from the Soxhlet extract of the synthetical "Graphote Smokes" soot(GS sample) by using a big Cosmosil Buckysep(Phenomenex) column(250 mm × 10 mm) with a large *** fractions isolated have been determined by high performance liquid chro-matography(HPLC) and laser desorption mass spectrometry(LDMS).It is found that there are different fullerenes molecules in different fractions with retention *** result indicates that fullerenes do exist in GS ***,it excludes the suspicion to some extent that fullerene molecules might be generated by the laser desorption process in the *** addition,it also provides the experimental basis for the study of natural higher fullerenes and might be helpful to figure out the question if higher fullerenes do exist in the natural samples.

关键词：富勒烯分子 HPLC 分离高效液相色谱仪煤烟吸烟石墨大容量注射剂

Three-step self-calibrating generalized phase-shifting interferometry

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Chinese physics B 2022年第8期31卷 234-240页

作者： Yu Zhang Institute of Materials physics College of ScienceNortheast Electric Power UniversityJilin 132012China State key laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130022China

An accurate and fast three-step self-calibrating generalized phase-shifting interferomertry(SGPSI) is proposed. In this approach, two new phase-shifting signals are constructed by the difference interferograms normalization and noise suppressing, then the unknown phase shift between the two difference phase-shifting signals is estimated quickly through searching the minimum coefficient of variation of the modulation amplitude, a limited number of pixels are selected to participate in the search process to further save time, and finally the phase is reconstructed through the searched phase shift. Through the reconstruction of phase map by the simulation and experiment, and the comparison with several mature algorithms, the good performance of the proposed algorithm is proved, and it eliminates the limitation of requiring more than three phase-shifting interferograms for high-precision SGPSI. We expect this method to be widely used in the future.

关键词： self-calibrating generalized phase-shifting interferomertry phase shift difference interferograms modulation amplitude

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