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Stochastic resonance in coupled weakly-damped bistable oscillators subjected to additive and multiplicative noises

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Acta Mechanica Sinica 2012年第2期28卷 505-510页

作者： Yan-mei Kang mei Wang yong Xie Department of Applied Mathematics School of Mathematics and StatisticsXi'an Jiaotong University710049 Xi'anChina State Key Laboratory of Mechanical Structure Strength and Vibration School of AerospaceXi'an Jiaotong University710049 Xi'anChina

With coupled weakly-damped periodically driven bistable oscillators subjected to additive and multiplicative noises under concern, the objective of this paper is to check to what extent the resonant point predicted by the Gaussian distribution assumption can approximate the simulated one. The investigation based on the dynamical mean-field approx- imation and the direct simulation demonstrates that the pre- dicted resonant point and the simulated one are basically co- incident for the case of pure additive noise, but for the case including multiplicative noise the situation becomes some- what complex. Specifically speaking, when stochastic res- onance （SR） is observed by changing the additive noise in- tensity, the predicted resonant point is lower than the sim- ulated one; nevertheless, when SR is observed by chang- ing the multiplicative noise intensity, the predicted resonant point is higher than the simulated one. Our observations im- ply that the Gaussian distribution assumption can not exactly describe the actual situation, but it is useful to some extent in predicting the low-frequency stochastic resonance of the coupled weakly-damped bistable oscillator.

关键词： Stochastic resonance Dynamical mean-field approximation Direct simulation

Deep-detection of formation boundary using transient multicomponent electromagnetic logging measurements

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Petroleum Science 2022年第3期19卷 1085-1098页

作者： Xi-yong Yuan Shao-Gui Deng Zhi-Qiang Li xiao-mei Han Xu-Fei Hu Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong266580China Sinopec Matrix Corporation QingdaoShandong266000China China Research Institute of Radiowave Propagation XinxiangHenan453000China China University of Petroleum—Beijing at Karamay KaramayXinjiang834000China

The maximum distance at which an electromagnetic(EM)logging while drilling(LWD)tool detects an approaching boundary is defined as the depth of detection(DOD).Ultra-deep detection capability of the transient multicomponent EM logging measurement is investigated ***,we adopt sine and cosine transform to calculate the transient multicomponent *** to the cosine transform,sine transform is more accurate in solving late-time ***,a time-domain geosignal is introduced to sense the *** show that DOD of this transient EM measurement can be up to tens of meters,including directionally ***,by studying the decay characteristics of different components with time,cross component is confirmed to decay much faster than the coaxial/coplanar components in the formation coordinate system.A pseudo-inversion is thereby proposed to determine the dip angle of anisotropic stratified *** simulation results indicate that this algebraic method can determine the true dip at some particular *** is still stable and valid even when considering random measurement ***,we establish the linear relationship between the time at which the half-point of geosignal curve appears and the distance to boundary(DTB),which would assist in the quick determination of DTB.

关键词： Time-domain Logging while drilling Formation boundary Dip angle Distance to boundary

Controlled Radical Photopolymerization of n-Butyl Methacrylate in Bluk Mediated by HTEMPO

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Chinese Chemical Letters 2006年第8期17卷 1109-1112页

作者： xiao Xuan LIU mei HAN Lun yong DUAN Guang Guo WU Department of Chemistry College of Science Shantou University Shantou 515063

Controlled radical photopolymerization of n-butyl methacrylate（n-BMA） mediated by 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy（HTEMPO） was carried out in bulk at ambient temperature. It was found that obtained n-BMA homopolymers exhibited narrow polydispersities of around 1.4, which was characterized by GPC. Plots of number-average molecular weight vs. conversion and Ln（[Mo]/[M]） vs. time were liner respectively, indicating that was a controlled photopolymerization.

关键词： photopolymerization nitroxide n-butyl methacrylate HTEMPO.

Synthesis and biological evaluation of lipid-soluble prodrugs of anethole dithiolthione

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Chinese Chemical Letters 2010年第12期21卷 1427-1429页

作者： mei Guan Wei Fan Shan Qian Rui Qi xiao yong Wu West China Hospital Sichuan University Chengdu 610041 China Key Laboratory of Drug Targeting of China Education Ministry West China School of Pharmacy Sichuan University Chengdu 610041 China

16 ADT carboxylate esters were prepared by means of esterification and these compounds were expected to increase the bioavailability of 4-hydroxyanehole *** vivo studies showed that ADT concentration of 3a in plasma was much higher than that of ATT during 120 *** 3a could reach blood peak values of ADT at 660.6 ng/mL which was about 14 times of that by ***,the acute toxicity assay indicated high safety of compound 3a that the maximum tolerated dose was no less than 3.25 g/kg.

关键词： Synthesis Anethole dithiolthione Liposoluble Bioavailability Prodrug

Technique of pulse electrochemical finishing in molds and dies

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 487-492页

作者： LI Hong-you LIU xiao-mei JIANG Kai-yong WANG Hui ZHOU Jin-jin Mould & Die Technology Research Center Huaqiao University Quanzhou 362021 China Mould & Die Technology Research Center Huaqiao University Quanzhou 362021 China Mould & Die Technology Research Center Huaqiao University Quanzhou 362021 China School of Mechanical Engineering Dalian University of Technology Dalian 116024 China School of Mechanical Engineering Dalian University of Technology Dalian 116024 China

Surface finishing is one of the most important processes in mould and die making. This process is necessary not only for smoothing the surface of die or mould, but also for removing the surface layer, which has been damaged by the preceding machining process and finally improve the performances and lifetime of moulds to a large extent. It has been reported that between 30% and 40% of the total time required to manufacture a die or mold is spent on finishing operations, most of which are performed by skilled workers employing traditional techniques. At present, key problems in mould and die finishing technology can improve the finishing efficiency, consistency and quality at reduced costs. A new and high efficiency unconventional finishing technology, pulse electrochemical finishing was introduced. Experiments were done in neutral nitrate electrolytes. The influence of electrolyte composition, intereletrode gap, finishing time, flow quality, current density, compositions of steel materials and pulse parameters on the resulting surface finishing was investigated. Results indicate that pulse parameters have important influence on operations finishing and the proper selection of pulse parameters can lead to both good smoothing efficiency and surface quality at low costs.

关键词： moulds dies pulse electrochemical finishing surface quality performance lifetime

Stability and Collective Excitation of Two-Dimensional BECs with Two-and Three-Body Interactions in an Anharmonic Trap

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Communications in Theoretical Physics 2009年第3期51卷 433-440页

作者： yong Wen-mei WEI Xiu-Fang ZHOU xiao-Yan XUE Ju-Kui College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China College of Science Gansu Agricultural University Lanzhou 730070 China Department of Physics Lanzhou City University Lanzhou 730070 China

The stability and collective excitation of Bose-Einstein condensates with both two- and three-body interactions in a two-dimensional anhaxmonic trap （i.e., harmonic plus quartic trap） are investigated. By using the variational method, the influence of the three-body interaction and the anharmonicity on the stability axe discussed in detail. It is found that the anhaxmonicity of the trap and the three-body interaction have significant effect on the stability and collective excitations of the system.

关键词： Bose Einstein condensates stability anharmonicity three-body interaction

Two Chiral Building Blocks for the Stereocontrolled Synthesis of Anti-and Syn-1,3-Diols

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Chinese Chemical Letters 2001年第9期12卷 765-766页

作者： yong WU mei GUAN Zheng XU Li Cheng xiao Chun WU School of Pharmacy Sichuan UniversityChengdu 610041 The First Hospital Sichuan UniversityChengdu 610041

Two chiral building blocks 1 and 2 for anti-and syn-1, 3-diols has been achieved in 8 steps and 7 steps respectively, starting from the readily available and inexpensive D (+)-xylose 3.

关键词： Chiral building block anti-and syn-1 3-diols D (+)-xylose

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略论工科院校人文环境的营造

唐山学院学报 2004年第2期17卷 33-34,66页

作者：郭智勇潘小妹南京工程学院社科部江苏南京210013 南京特殊职业技术学院江苏南京210013

工科院校人文素质教育实施的一个重要方面在于营造一个良好的人文氛围。通过对工科院校人文氛围建设认识的清理,以及在改革课程体系、重塑专业教育中的人文精神等方面的努力,期待为工科院校人文素质教育的深入开展提供有益的借鉴。

关键词：工科院校人文环境人文素质人文氛围

Spatially resolved properties of supernova host galaxies in SDSS-IV MaNGA

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Research in Astronomy and Astrophysics 2021年第12期21卷 383-395页

作者： Hong-Xuan Zhang Yan-mei Chen yong Shi Min Bao xiao-Ling Yu School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Collaborative Innovation Center of Modern Astronomy and Space Exploration Nanjing 210093China

We crossmatch galaxies from Mapping Nearby Galaxies at Apache Point Observatory with the Open Supernova Catalog,obtaining a total of 132 SNe within MaNGA *** 132 SNe can be classified into 67 Type Ia and 65 Type *** study the global and local properties of supernova host galaxies *** Ia SNe are distributed in both star-forming galaxies and quiescent galaxies,while Type CC SNe are all distributed along the star-forming main *** the stellar mass increases,the Type Ia/CC number ratio *** find:(1)there is no obvious difference in the interaction possibilities and environments between Type Ia SN hosts and a control sample of galaxies with similar stellar mass and SFR distributions,except that Type Ia SNe tend to appear in galaxies which are more bulge-dominated than their *** Type CC SNe,there is no difference between their hosts and the control galaxies in galaxy morphology,interaction possibilities as well as environments;(2)compared to galaxy centers,the SN locations have smaller velocity dispersion,lower metallicity,and younger stellar *** is a natural result of radius gradients for all these *** SN location and its symmetrical position relative to the galaxy center,as well as regions with similar effective radii have very similar[Mg/Fe],gasphase metallicity,gas velocity dispersion and stellar population age.

关键词： galaxies:general galaxies:abundances supernovae:general techniques:spectroscopic