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Dynamic analysis of granite rockburst based on the PIV technique

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International Journal of Mining Science and Technology 2015年第2期25卷 275-283页

作者： Wang Hongjian liu Da'an Gong Weili li liyun Key Laboratory of Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences School of Mechanics and Civil Engineering China University of Mining & Technology

This paper describes the deep rockburst simulation system to reproduce the granite instantaneous rockburst *** on the PIV(Particle Image Velocimetry)technique,quantitative analysis of a rockburst,the images of tracer particle,displacement and strain fields can be obtained,and the debris trajectory *** to the observation of on-site tests,the dynamic rockburst is actually a gas–solid high speed flow process,which is caused by the interaction of rock fragments and surrounding *** the help of analysis on high speed video and PIV images,the granite rockburst failure process is composed of six stages of platey fragment spalling and debris ***,the elastic energy for these six stages has been calculated to study the energy *** results indicate that the rockburst process can be summarized as:an initiating stage,intensive developing stage and gradual decay *** research will be helpful for our further understanding of the rockburst mechanism.

关键词： Rock mechanics Instantaneous rockburst Particle image velocimetry Energy variation

Analysis with NMR localized spectroscopy of rat brain in vivo and ex vivo

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Chinese Science Bulletin 1998年第2期43卷 140-142页

作者： Guangliang Ding Xiaodong Zhang liyun li Chaohui Ye Chinese Acad Sci Wuhan Inst Phys & Math Lab Magnet Resonance & Atom & Mol Phys Wuhan 430071 Peoples R China

The volume-selected MRS of rat brain was performed on a 200 MHz broad horizontal-bore nuclear magnetic resonance imaging spectrometer. The localized proton spectroscopy of rat brain was acquired using the double spin-echo pulse sequence (PRESS) to select the position and size of the volume. Water signal was suppressed by CHESS sequence which was composed of chemical shift selective rf pulses and dephasing gradients. The parameter TE was taken as 40 ms and 135 ms in the experiment. The localized MRS of the rat brain with the status of live and death was obtained in various TE values. Results showed that volume-selected proton MRS of the rat brain in vivo with longer TE consisted mainly of signals produced by N-acetylaspartate (NAA), creatine (Cre), choline (Cho) and the lactate spectral peak occurred in the MRS of the rat brain ex vivo. On the other hand, the MRS of the rat brain with shorter TE contained glutamine/glutamate and lipid signals besides those signals mentioned previously. Although the information abstracted from the MRS of the rat brain with shorter TE may be more than that with longer TE, the spectral resolution of the MRS with shorter TE was slightly worse. In addition, it might indicate that the absolute concentration of NAA was decreased in dead rat brain because the SNR of NAA peak in the MRS ex vivo got lower.

关键词： NMR localized spectroscopy rat brain.

New evidence for microstructural evolution model of acid-activated montmorillonite

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Chinese Science Bulletin 2002年第9期47卷 761-765页

作者： HE Hongping GUO Jiugao liN Hongfu li liyun Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Zhejiang Foreign Trade Company for Industrial Minerals Hangzhou 310000China Laboratory of Magnetic Resonance and Atom and Molecular Physics Wuhan Institute of PhysicsChinese Academy of SciencesWuhan 430071China

Ca-montmorillonite samples from Choushan treated at various acid concentrations were studied using chemical analysis, XRD, 29Si and 27A1 MAS NMR, to investigate the microstructure of the activated montmorillonites. With the increase of acid concentration and dissolution of cations of montmorillonite, the intensity of d(001) decreased obviously and significant changes of the microstructure of Si and Al occurred. There were two new types of structural units of Si atoms formed: (SiO)3SiOH units and Q4(0A1) units. For Al atoms, in the course of activation, the removal of one of a pair of octahedral aluminium atoms from montmorillonite removed two hydroxyl groups and left the other aluminum of the pair in the four-fold coordination. The 27A1 signal at 5 54.0 corresponding to AliV arose from the four-coordinated Al in the octahedral sheet. This study first confirmed, by 29Si and 27A1 MAS NMR spectra, that the model of microstructural evolution for activated montmorillonite postulated by Thomas et al. (1950)

关键词： montmorillonite 29Si and 27A1 MAS NMR structural evolution.

Structural state of adularia from Hishikari,Japan

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Chinese Science Bulletin 2001年第11期46卷 950-954页

作者： ZHOU lingdi GUO Jiugao liU Binguang li liyun Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Laboratory of Magnetic Resonance and Atom and Molecular Physics Wuhan Institute of PhysicsChinese Academy of SciencesWuhan 430071China

Adularia sample was collected from epithermal Au-, Ag-bearing quartz-adularia veins from Hishikari, Japan. This adularia is rich in K, Or=94.63, clear, transparent, fine-grained and closely associated with quartz. In this study, it was determined by XRD, IR and 29Si, 27A1 MAS NMR methods. The adularia studied is of high sanidine with triclinic domains in it. The occupancy of Al 2t1=0.60, IR ordering θ=0.15.29Si NMR spectrum of this adularia shows a broad triplet peak, i.e. 3 poorly separated peaks at -94.9, -96.7, -99.9. This kind 29Si NMR spectrum for natural high sanidine has never been reported before. And the 27A1 NMR spectrum gives an asymmetry peak with chemical shift at 58.7 extending slightly to the low frequency. Under a violent boiling environment, Hishikari adularia rapidly crystallized from a supersaturated solution.

关键词： adularia structural state high sanidine XRD IR 29Si NMR 27Al NMR Hishikari gold deposit.

Quantitative amendment of high-field ^(13)C NMR spectra of coals

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Chinese Science Bulletin 1997年第10期42卷 807-809页

作者： YANG Baolian, li liyun and YE ChaohuiLaboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China

HIGH-RESOLUTION solid state 13C NMR spectroscopy has been a useful tool for the study of *** the use of cross polarization（CP）,magic angle spinning（MAS）and protonhigh-power decoupling（HPD）techniques,high-resolution solid state 13C NMR spectra ofcoals can be obtained and the coal aromaticity（fa）can be measured *** aromaticityis defined as the ratio of aromatic carbon atoms to the total carbon atoms in *** pa-

关键词： 13C NMR coal structure quantitative amendment.

Energy analysis and criteria for structural failure of rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2009年第1期1卷 11-20页

作者： Heping Xie liyun li Ruidong Peng Yang Ju Sichuan University Chengdu 610065 China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Teehnology Beijing 100083 China

The intrinsic relationships between energy dissipation,energy release,strength and abrupt structural failure are key to understanding the evolution of deformational processes in *** and experimental studies confirm that energy plays an important role in rock deformation and *** energy from external forces produces damage and irreversible deformation within rock and decreases rock strength over *** failure of rocks is caused by an abrupt release of strain energy that manifests as a catastrophic breakdown of the rock under certain *** strain energy released in the rock volume plays a pivotal role in generating this abrupt structural failure in the *** this paper,we propose criteria governing（1） the deterioration of rock strength based on energy dissipation and（2） the abrupt structural failure of rocks based on energy *** critical stresses at the time of abrupt structural failure under various stress states can be determined by these *** an example,the criteria have been used to analyze the failure conditions of surrounding rock of a circular tunnel.

关键词： energy dissipation energy release strength deterioration structural failure breakage size

柳宗元“交以为师”师生观的哲学意蕴与教育价值

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当代教育论坛 2018年第5期 61-67页

作者：黎利云衡阳师范学院教育学系

柳宗元的"交以为师"师生观是我国优秀传统文化的重要组成部分。该理论内涵丰富,是一种具有辩证性、发展性、生本性、自知性、民主性等哲学意蕴的教育思想。该理论既是价值观,也是方法论。在"互联网+教育"的时代背景下,实践"交以为师"能... 详细信息

柳宗元的"交以为师"师生观是我国优秀传统文化的重要组成部分。该理论内涵丰富,是一种具有辩证性、发展性、生本性、自知性、民主性等哲学意蕴的教育思想。该理论既是价值观,也是方法论。在"互联网+教育"的时代背景下,实践"交以为师"能产生多方面的积极意义:一是有利于教师走出师道尊严误区从而建立良好的师生关系;二是有利于学生发挥主观能动性提高学习效率;三是有利于发展学生个性实现学生个性发展;四是有利于达成教育民主实现师生的心灵解放。

关键词：柳宗元交以为师哲学意蕴教育民主

Dynamic analysis of granite rockburst based on the PIV technique

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Dynamic analysis of granite rockburst based on the PIV techn...

李丽芸从“情志不节”角度诊治复发性流产经验

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

This paper describes the deep rockburst simulation system to reproduce the granite instantaneous rockburst *** on the PIV(Particle Image Velocimetry)technique,quantitative analysis of a rockburst,the images of tracer particle,displacement and strain fields can be obtained,and the debris trajectory *** to the observation of on-site tests,the dynamic rockburst is actually a gas-solid high speed flow process,which is caused by the interaction of rock fragments and surrounding *** the help of analysis on high speed video and PIV images,the granite rockburst failure process is composed of six stages of platey fragment spalling and debris ***,the elastic energy for these six stages has been calculated to study the energy *** results indicate that the rockburst process can be summarized as:an initiating stage,intensive developing stage and gradual decay *** research will be helpful for our further understanding of the rockburst mechanism.

关键词： Rock mechanics Instantaneous rockburst Particle image velocimetry Energy variation

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中国医药导报 2017年第17期14卷 178-180页

作者：李茵王秀芳刘群徐珉李丽芸广州中医药大学第二临床医学院广东广州510405 广东省中医院妇科广东广州510120

本文浅析岭南中医妇科名家李丽芸教授从"情志不节"角度诊治复发性流产的经验,并撷取病案,以飨同道,希冀能为临床工作提供些许借鉴,其认为情志不节则冲任不能相资,气血不能相和,胎失所系,故而发为滑胎。治疗时推崇孕前调理,当从肝论治;... 详细信息

本文浅析岭南中医妇科名家李丽芸教授从"情志不节"角度诊治复发性流产的经验,并撷取病案,以飨同道,希冀能为临床工作提供些许借鉴,其认为情志不节则冲任不能相资,气血不能相和,胎失所系,故而发为滑胎。治疗时推崇孕前调理,当从肝论治;既孕防流,以静养胎;欲治其人,先治其心。

关键词：复发性流产情志不节名医经验李丽芸