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A PRELIMINARY STUDY ON SPECTRAL CHARACTERISTICS OF ELECTRON DENSITY FLUCTUATION IN THERMOSPHERE

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Chinese Science Bulletin 1989年第1期34卷 85-86页

作者：易帆李钧梁百先 Wuhan Institute of Physics Academia Sinica DepartmentofSpacePhysics Wuhan University

Since charged particles in ionosphere are governed by various factors, their varying manner is remarkably complicated. For this system with complicated varying manner, in order to study its temporal and spatial struct... 详细信息

关键词： manner remarkably governed carry charged preserved fluctuation ordinary collection Passage

Laser induced photoemission electron and the generation of high Rydberg states of atoms and molecules

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Chinese Science Bulletin 1998年第19期43卷 1616-1620页

作者： Li Wang Haiyang Li Jiling Bai Richang Lu Acad Sinica Dalian Inst Chem Phys State Key Lab Mol React Dynam Dalian 116023 Peoples R China

Laser induced photoemission electron was produced by directing 532 nm and/or 355 nm onto stainless steel plate on a time of flight mass spectrometer. Multiple charged ions and high Rydberg states of atoms or molecules were successfully generated by impacts of the photoemission electrons. The high Rydberg states ( n ～40-100) thus produced were separated from ions, produced by direct electron impact ionization, by a 3 V DC electric field and then ionized by a delayed pulsed HV electric field in a ZEKE-PFI manner. Relationship between generation/property of high Rydberg states of atoms/molecules and experimental conditions could be investigated. Relationship between the electron accelerating voltage and high Rydberg states of Ar was described.

关键词： photoemission electron multiple charged ions high Rydberg states.

STRUCTURAL STUDIES ON THE OLIGOMERS FROM THE POLYSACCHARIDE OF GRACILARIA TEXTORII (RHODOPHYTA) USING β-AGARASE AND 13C-NMR SPECTROSCOPY

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Chinese Journal of Oceanology and Limnology 1990年第2期8卷 135-149页

作者：纪明侯 M.Lahaye W.Yaphe Institute of Oceanology. Academia Sinica Qingdao Department of Microbiology and Immunology McGill University Montreal Canada INRA-LBTG B. P. 527 44026 Nantes Cedex France Department of Microbiology and Immunology McGill University Montreal Canada

The 60% ethanolic extract from Gracilaria textorii (Rhbdophyta) was degraded with B- agarase, and certain charged (sulfated) and neutral oligosaccharides were separated by using DEAE Sephadex A 25 and Bio- gel P6 , P2 chromatographic techniques . Some of the charged oligomers were verified to be neoagarotetraose - 63- sulfate ( DP2 ). neoagarohexaose- 63 > 65 - disulfate ( DP3 ) and neoagarooctaose- 63, 65, 67-trisulfate (DP4) by using 13C-and ’H-NMR spectroscopy . One neutral oligomer was assumed to be a mixture of methylated neoagarotetraoses (DP2 ) by 1H-NMR spectroscopy .These oligomers assigned by their chemical shifts may be used as the model compounds for the structural investigation of the agar- type sulfated polysaccharides using the B- agarase degradation method .

关键词： oligomer neutral Gracilaria degraded verified RHODOPHYTA USING charged agarose reagent

POLYPYRROLE FILM-MODIFIED ELECTRODE DOPED WITH COLLOIDAL CUPRIC HEXACYANOFERRATE

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Chinese Science Bulletin 1992年第4期37卷 346-347页

作者：张文斌李一峻董绍俊 Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Academia Sinica Changchun 130022 PRC To whom correspondence shouid be addressed

To explore the possibility of the functionalization of polypyrrole （PPy）, we prepared a polypyrrole film-modified dectrode containing colloidal cupric hexacyanoferrate （CuHCF） by making use of the characterization of negatively charged colloidal particles. CuHCF was obtained by mixing CuSO4 and K4Fe（CN）6 solutions in a molar ratio of 2: 1. The sediment was washed with water for 4 times, then dispersed ultrasonically in

关键词： colloidal dispersed mixing possibility molar charged dispersive electrolysis negatively scanned

RESEARCH ON AMAGNETIC FIELD IN ELECTROLYTIC LAPPING

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Chinese Journal of Mechanical Engineering 1999年第1期12卷 64-70页

作者： Chen Yuquan Li ZhenjiaDept.of Mechanical Engineering, Harbin University of Science & TechnologyLi WeigangHarbin Institute of Science & Technology

Taking electrolytic lapping stainless steel for example, the principle of electrolytic lapping with a magnetic field is described, the movement of charged particles in the magnetic field is analyzed in tems of theory. Using a computer, the motion loci of the charged particles in the magnetic field are simulated. The theory and the experiment show that the magnetic field can accelerate the diffusion and mobility of the charged particles, accelerate the electrochemical reaction and reduce the surface roughness of the work more quickly, which improves the lapping efficiency.

关键词： Magnetic field Electrolytic Lapping charged particles Computer simulation

A Review on Electrodynamic Influence of Atmospheric Processes to the Ionosphere

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Open Journal of Earthquake Research 2020年第2期9卷 113-141页

作者： Valery M. Sorokin Vitaly M. Chmyrev Masashi Hayakawa Institute of Terrestrial Magnetism Ionosphere and Radio Wave Propagation (IZMIRAN) Russian Academy of Sciences Troitsk Moscow Russia Institute of Physics of the Earth Russian Academy of Sciences Moscow Russia Hayakawa Institute of Seismo Electromagnetics (Hi-SEM) Co. Ltd. University of Electro-Communications (UEC) Chofu Japan

This work is an attempt to critically analyze the existing theoretical models of the impact of earthquake preparation processes on the state of the earth’s atmosphere and ionosphere in the zone of growing seismic activity, as well as the mechanisms of formation and transfer of disturbances in various media over the earthquake center. The determining factor (criterion) of the analysis is the degree of compliance of the simulation results with experimental data obtained at various phases of earthquake development by direct and remote diagnostic methods using ground and aerospace technologies. The key role is played by the model’s compliance with the results of measuring electric fields and currents in the near-ground atmosphere and ionosphere, small-scale ionospheric inhomogeneities and correlated field-aligned currents and electromagnetic ULF/ELF emissions. A full-fledged model should also explain the origin of such seismic related phenomena as the generation in the troposphere and over-horizon propagation of pulsed VHF radiation, thermal effects and associated IR emissions as well as the modification of plasma distribution in the D, E and F layers of the ionosphere. The use of this criterion in the analysis allowed us to identify a theoretical model that most fully describes the totality of the above-mentioned experimental data within a single physical mechanism. This is an electrodynamic model based on the perturbation of the conductivity current in the global atmosphere—ionosphere electric circuit due to the injection of charged aerosols into the atmosphere during the preparation and development of an earthquake. The present paper describes this model and the formation mechanisms of related phenomena in the atmosphere and ionosphere, which can be considered as short-term precursors to earthquakes.

关键词： Earthquake (EQ) Precursors charged Aerosol Injection Global Electric Circuit Ionospheric Irregularities ULF/ELF Electromagnetic Emissions Ran-dom Discharges Radiation Over-the-Horizon VHF Propagation

The Evolution of the Charge Density Distribution Function for Spherically Symmetric System with Zero Initial Conditions

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World Journal of Condensed Matter Physics 2014年第1期4卷 33-38页

作者： Evgeny E. Perepelkin Natalia G. Inozemtseva Alex A. Zhavoronkov Faculty of Physics Moscow State University Moscow Russian Federation International University “Dubna” Dubna Russian Federation Moscow Institute of Physics and Technology Dolgoprudny Russian Federation

The evolution of the charge density distribution function is simulated for both the case of a uniformly charged sphere with zero initial conditions and for the case of a non-uniform charged sphere. For the case of a uniformly charged sphere the comparison of a numerical result and an exact analytical demonstrated the agreement between the results. The process of “scattering” of a charged system under the influence of its own electric field has been illustrated on the basis of both the particle-in-cell method and the solution of the Cauchy problem for vector functions of the electric field and vector velocity field of a charged medium.

关键词： non-uniform charged sphere Cauchy problem charge density distribution particle-in-cell

THEORETICAL CALCULATION OF THE ANOMALOUS CERENKOV RADIATION PRODUCED IN THE AIR

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Chinese Science Bulletin 1983年第2期28卷 184-189页

作者：张子平杨炳忻奚富云徐克尊 Department of Modern Physics University of Science and Technology of China Hefei Department of Modern Physics University of Science and Technology of China Hefei? INTRODUCTION Cerenkov radiation will be produced when the velocity of charged particles passing through a medium is faster than the phase velocity of light in the same medium. The moving direction of the radiation photons is determined by the following formula:

Ⅰ. INTRODUCTION Cerenkov radiation will be produced when the velocity of charged particles passing through a medium is faster than the phase velocity of light in the same medium. The moving direction of the radiation... 详细信息

关键词： faster satis passing charged anomalous weights vibrational oscillator reversal ingle

ELECTRONIC STRUCTURE OF ALKALI-METAL COMPLEX-OF CROWN ETHER. 12-C-4~*

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Chinese Science Bulletin 1980年第4期25卷 296-299页

作者：游效曾李重德余耀华包家伟 Department of Chemistry Nanjing University

Crown ether is a new type coordinating agent. It has a hydrophilic internal cavity which can accommodate charged or neutral molecules, and also a hydrophobic external frame-work. It has been widely used in the making of ionic selective electrodes and as a. phase-transfer agent for organic synthesis and inorganic mimic of biological membranes.

关键词： hydrophilic hydrophobic inorganic ionic neutral mimic accommodate Crown charged orbital