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The low-latitude sodium layer:comparative data from lidar observations at Hainan,China and São Paulo,Brazil

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Earth and Planetary Physics 2025年第1期9卷 39-53页

作者： Fang Wu jing Jiao GuoTao Yang LiFang Du ZhengKuan Liu HaoRan Zheng JiXin Guo ShaoHua gong YaJun Zhu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Hainan National Field Science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China China-Brazil Joint Laboratory for Space Weather NSSC/INPESão Josédos Campos 12227-010Brazil School of Physics and Electronics Engineering Hainan Normal UniversityHaikou 571158China

Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude *** sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s *** paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the *** low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in ***,maximal Na density over Brazil is greater than that over *** variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before *** variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain *** suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.

关键词： metallic sodium layer seasonal variation nocturnal variation lidar

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杭州西湖藻类动态模型研究

水生生物学报 2000年第2期24卷 143-149页

作者：裴洪平马建义周宏蔡景现李共国浙江大学杭州310028 浙江农技师师专宁波315101

该模型按照年度来描述西湖四类藻类（蓝藻门、绿藻门、隐藻门、硅藻门）的动态变化。结果表明，模型作出的状态变量的描述是理想的，并且对于系统强制函数改变能给予合理响应。模型还对引水量，引水或溪流的含磷量及疏竣湖泥量的改变给... 详细信息

该模型按照年度来描述西湖四类藻类（蓝藻门、绿藻门、隐藻门、硅藻门）的动态变化。结果表明，模型作出的状态变量的描述是理想的，并且对于系统强制函数改变能给予合理响应。模型还对引水量，引水或溪流的含磷量及疏竣湖泥量的改变给水体带来的变化进行了预测。

关键词：藻类生态模型杭州西湖

Numerical study of optical trapping properties of nanoparticle on metallic film with periodic structure

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Chinese Physics B 2019年第2期28卷 223-233页

作者： Cheng-xian Ge Zhen-Sen Wu jing Bai Lei gong School of Physics and Optoelectronic Engineering Xidian University School of Photoelectric Engineering Xi'an Technological University

Based on the three-dimensional dispersive finite difference time domain method and Maxwell stress tensor equation,the optical trapping properties of nanoparticle placed on the gold film with periodic circular holes are investigated numerically. Surface plasmon polaritons are excited on the metal-dielectric interface, with particular emphasis on the crucial role in tailoring the optical force acting on a nearby nanoparticle. Utilizing a first order corrected electromagnetic field components for a fundamental Gaussian beam, the incident beam is added into the calculation model of the proposed method. To obtain the detailed trapping properties of nanoparticle, the selected calculations on the effects of beam waist radius, sizes of nanoparticle and circular holes, distance between incident Gaussian beam and gold film, material of nanoparticle and polarization angles of incident wave are analyzed in detail to demonstrate that the optical-trapping force can be explained as a virtual spring which has a restoring force to perform positive and negative forces as a nanoparticle moves closer to or away from the centers of circular holes. The results of optical trapping properties of nanoparticle in the vicinity of the gold film could provide guidelines for further research on the optical system design and manipulation of arbitrary composite nanoparticles.

关键词： surface plasmon periodic circular holes optical trapping force Maxwell stress tensor gold film

Effect of Retained Austenite on Corrosion Behavior of Ultrafine Bainitic Steel in Marine Environment

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 717-731页

作者： xian Zhang Li gong Yanpeng Feng Zhihui Wang Miao Yang Lin Cheng jing Liu Kaiming Wu Hubei Province Key Laboratory of Systems Science in Metallurgical Process The State Key Laboratory of Refractories and MetallurgyCollaborative Innovation Center for Advanced SteelsWuhan University of Science and TechnologyWuhan430081China School of Chemistry Chemical Engineering and Life SciencesWuhan University of TechnologyWuhan430070China

In this study,the impact of retained austenite on corrosion initiation,propagation,and resistance of ultrafine bainitic steels in marine environments based on the one-step and two-step bainitic isothermal transformation was investigated using a combination of theoretical calculations and experimental *** to the results,the microstructure of ultrafine bainitic steels was composed of parallel arranged bainite ferrite(BF)and retained austenite(RA).The fraction of the block RA was significantly reduced,whereas the amount of the film RA increased through the two-step bainitic *** the initial stage of corrosion,micro-galvanic effects occurred between the multiphases due to the difference in nobility,leading to the selective dissolution of BF sheaves,which is adjacent to the block RA in the one-step bainitic ***,uniformly distributed film RA in the two-step bainitic steel acted as a barrier against corrosion *** electrochemical measurements and neutral salt spray tests revealed a relatively lower corrosion rate for the two-step bainitic steel,indicating a higher corrosion resistance than the one-step bainitic *** corrosion products layer mainly consisted ofα-FeOOH,γ-FeOOH,and Fe_(3)O_(4),which were stable and favorable for the formation of a protective rust layer.

关键词： Ultrafine bainitic steel Retained austenite Marine environment Corrosion behavior First principle modeling

Laser-Induced Distortions and Disturbance Propagation of Delocalized Electronic States in Monatomic Carbon Chains

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Chinese Physics Letters 2012年第6期29卷 219-222页

作者： YANG gong-xian gong Xiu-Fang School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048 Dongfang Turbine Co. LtdDeyang 618000

Tight-binding electron-ion dynamics of carbon chains pumped by intense laser pulses are performed to study the interactions between monatomic carbon chains and ***-induced distortions of carbon chains,which are enhanced by a long wavelength laser,are *** carbon chains with a strong laser beam focused on one terminal are simulated to study the disturbance of electronic *** the superposition of delocalized π band states,the disturbance propagates from the illuminated area to the non-illuminated area in a velocity ofabout 106 m/s at 0 K,and this velocity is weakened at room temperature due to the localization effect of thermal fluctuation.

关键词： pumped chains atomic

Identifi cation of model structure parameters via combination of AFMM and ARX from seismic response data

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 411-423页

作者： gong Maosheng Sun jing Xie Lili Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics CEA Institute of Civil Engineering Heilongjiang University

To identify the model structure parameters in shaking table tests from seismic response, especially from time- varying response records, this paper presents a new methodology by combining the online recursive Adaptive Forgetting through Multiple Models （AFMM） and offtine Auto-Regression with eXogenous variables （ARX） model. First, the AFMM is employed to detect whether the response of model structure is time-invariant or time-varying when subjected to strong motions. Second, if the response is time-invariant, the modal parameters are identified from the entire response record, such as the acceleration time-history using the ARX model. If the response is time-varying, the acceleration record is divided into three segments according to the accurate time-varying points detected by AFMM, and parameters are identified by only using the tail segment data, which is time-invariant and suited for analysis by the ARX model. Finally, the changes in dynamic properties due to various strong motions are obtained using the presented methodology. The feasibility and advantages of the method are demonstrated by identifying the modal parameters of a 12-story reinforced concrete （RC） frame structure in a shaking table test.

关键词： parameter identification time-varying response model structure shaking table test

Enhancement in Magnetorheological Effect of Magnetorheological Elastomers by Surface Modification of Iron Particles

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Chinese Journal of Chemical Physics 2008年第1期21卷 87-92页

作者： Wan-quan Jiang jing-jing Yao Xing-long gong Lin Chen Department of Chemistry University of Science and Technology of China Hefei 230026 China CA5 Key Laboratory of Mechanical Behavior and Design of Materials Department of Mechanics andMechanical Engineering University of Science and Technology of China Hefei 230027 China

In order to obtain magnetorheological （MR） elastomers with high magnetorheological effect, a family of anisotropic rubber-based MR elastomers was developed using a new form of chemical modification. Three different kinds of surfactants, i.e. anionic, nonionic and compound surfactants, were employed separately to modify iron particles. The MR effect was evaluated by measuring the dynamic shear modulus of MR elastomer with a magneto-combined dynamic mechanical analyzer. Results show that the relative MR effect can be up to 188% when the iron particles are modified with 15% Span 80. Besides the surface activity of Span 80, however, such high modifying effect is partly due to the plasticizing effect of Span 80. Compared with the single surfactant, the superior surface activity of compound surfactant makes the relative MR effect reach 77% at a low content of 0.4%. Scanning electron microscope observation shows that the modification of compound surfactant results in perfect compatibility between particles and rubber matrix and special self-assembled structure of particles. Such special structure has been proved beneficial to the improvement of the relative MR effect.

关键词： Magnetorheological elastomers Shear modulus Surfactant Microstructure

Natural gas hydrate shell model in gas-slurry pipeline flow

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Journal of Natural Gas Chemistry 2010年第3期19卷 261-266页

作者： jing gong Bohui Shi Jiankui Zhao Beijing Key laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum Beijing 102249 China China National Oil and Gas Exploration and Development Corporation Beijing 100034 China

A hydrate shell model coupled with one-dimensional two-fluid pipe flow model was established to study the flow characteristics of gas-hydrate slurry flow *** hydrate shell model was developed with kinetic limitations and mass transfer limitations,and it was solved by Euler *** analysis of influence factors was *** was found that the diffusion coefficient was a key parameter in hydrate forming *** the hydrate kinetics model and the contacting area between gas and water,the hydrate shell model was more close to its practical situations.

关键词： natural gas hydrate shell model gas-slurry pipeline flow

Heat Treatment of Spray Deposition SiCp/6066 Aluminum Matrix Composites

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Journal of Central South University 2000年第2期12卷 61-64页

作者： gong Hao-ran Li Wen-xian Department of Materials Science and Engineering Central South University of TechnologyChangsha 410083China

Heat treatment of spray deposition 10% SiCp/6066 ( φ (SiCp)=10%) composites was investigated by means of hardness measurement. The results show that heat treatment technology is influenced by the presence of SiC particles. Compared with the base alloy 6066, the composites have lower burning temperature and is burnt at 540 ℃ due to the enrichment of Mg and Cu atoms in the SiCp/6066 interfaces. As a result, solution treatment of the composites should be carried out at lower temperature. The aging parameter values such as the aging temperature, the precipitation temperature of β′ and β phases, as well as the peak aging time, become lower. The optimum heat treatment process conditions are that the composites are solution treated at 515 ℃ and aged at 165 ℃ for 5 h.

关键词： spray deposition composites solution treatment temperature aging