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山银花花色形成研究进展

广西科学 2024年第03期31卷 486-491页

作者：吕玲玲鲁杏欢李立云怀化学院生物与食品工程学院民族药用植物资源研究与利用湖南省重点实验室湘西药用植物与民族植物学湖南省高校重点实验室

山银花花色类型较少,常规品种在不同发育阶段依次呈现出绿色、白色和黄色。山银花中的色素主要有叶绿素、类胡萝卜素和类黄酮。本文对山银花花色类型、花色素的种类及其含量与花色的关系、不同花色时期绿原酸含量的变化、类黄酮生物合... 详细信息

山银花花色类型较少,常规品种在不同发育阶段依次呈现出绿色、白色和黄色。山银花中的色素主要有叶绿素、类胡萝卜素和类黄酮。本文对山银花花色类型、花色素的种类及其含量与花色的关系、不同花色时期绿原酸含量的变化、类黄酮生物合成途径相关基因表达对花色的影响等进行综述,并对今后山银花花色的研究方向进行展望,为山银花花色形成机理提供参考。

关键词：山银花花色类黄酮物质类胡萝卜素基因

Seismic damage of highway bridges during the 2008 Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 263-273页

作者： Han Qiang Du Xiuli liu Jingbo li Zhongxian li liyun Zhao Jianfeng Lab. of Urban Security ＆ Dixaster Engineering of MOE Beijing University of Technology Beijing 100124 China Key Department of Civil Engineering Tsinghua University Belling 100084 China College of Civil Engineering Tianjin University Tianjin 200072 China College of Civil Engineering Qingdao Technological University Qingdao 266033 China

Many highway bridges were severely damaged or completely collapsed during the 2008 Wenchuan earthquake. A field investigation was carried out in the strongly affected areas and over 320 bridges were examined. Damage to some representative highway bridges is briefly described and a preliminary analysis of the probable causes of the damage is presented in this paper. The most common damage included shear-flexural failure of the pier columns, expansion joint failure, shear key failure, and girder sliding in the transversal or longitudinal directions due to weak connections between girder and bearings. Lessons learned from this earthquake are described and recommendations related to the design of curved and skewed bridges, design of bearings and devices to prevent girder collapse, and ductility of bridge piers are presented. Suggestions for future seismic design and retrofitting techniques for bridges in moderate to severe earthquake areas are also proposed.

关键词： Wenchuan earthquake seismic damage seismic design highway bridge field investigation

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.

Plackett-Burman设计结合Box-Behnken响应面法筛选草乌甲素纳米乳凝胶贴膏的处方

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西北药学杂志 2024年第1期39卷 92-98页

作者：何雨晓李丽云孙文强丁江生周云龙云南中医药大学昆明650500 云南省药物研究所昆明650111 云南省中药和民族药新药创制企业重点实验室昆明650111

目的优化草乌甲素纳米乳凝胶贴膏基质的处方。方法在Plackett-Burman设计、最陡爬坡实验的基础上,以甘油、酒石酸、纯化水用量作为变量,以初黏力、持黏力、感官评价的综合评分为评价指标,用Box-Behnken响应面法优化草乌甲素纳米乳凝胶... 详细信息

目的优化草乌甲素纳米乳凝胶贴膏基质的处方。方法在Plackett-Burman设计、最陡爬坡实验的基础上,以甘油、酒石酸、纯化水用量作为变量,以初黏力、持黏力、感官评价的综合评分为评价指标,用Box-Behnken响应面法优化草乌甲素纳米乳凝胶贴膏基质的处方。结果最优处方为甘油用量40.877 g,酒石酸用量0.294 g,纯化水用量42.491 g,综合评分为94.937分。结论建立的方法稳定、可靠、预测性能优良,此方法可用于优化草乌甲素纳米乳凝胶贴膏基质的处方。

关键词：草乌甲素纳米乳凝胶贴膏 Plackett-Burman设计

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.

Immunologic characteristics and predictive risk factors of primary Sjögren’s syndrome complicated with malignant lymphoma:A multicenter case-control study

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Chinese Medical Journal 2024年第10期137卷 1252-1254页

作者： Yuebo Jin linqing Hou Hao li liyun Zhang Yuanhong Peng Naidi Wang Jing He Department of Rheumatology and Immunology Beijing Key Laboratory for Rheumatism Mechanism and Immune DiagnosisPeking University People’s HospitalBeijing 100044China Department of Rheumatology and Immunology Linfen Third People’s HospitalLinfenShanxi 041000China Department of Rheumatology and Immunology Huabei Petroleum Administration Bureau General HospitalCangzhouHebei 062552China Affiliated Hospital of North Sichuan Medical College NanchongSichuan 637000China

To the Editor:Primary Sjögren’s syndrome(pSS)is a multi-systemic autoimmune disease characterized by the exocrine gland(mainly salivary and lacrimal glands)involvement,leading to xerostomia and xerophthalmia.[1]The course of pSS is relatively slow,but patients with pSS had higher risk of overall cancer,including malignant lymphoma(ML).[2]It is widely known that all-cause mortality rates were not increased in pSS patients as compared with healthy ***,secondary lymphoproliferative disease was an important cause of excess mortality.

关键词： mortality lymphoma malignant