Journal of Magnetic Resonance, Series B最新文献_第9页

Fully13C-Refocused Multidimensional13C-Edited Pulse Schemes Using Broadband Shaped Inversion and Refocusing Pulses 利用宽带形状反转和重聚焦脉冲的全13c重聚焦多维13c编辑脉冲方案

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0110

Kenji Ogura , Hiroaki Terasawa , Fuyuhiko Inagaki

引用次数: 21

Effect of Cation Binding on the Proton Chemical Shifts and the Spin–Spin Coupling Constant of Citrate 阳离子结合对柠檬酸盐质子化学位移和自旋耦合常数的影响

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0109

Marinette van der Graaf, Arend Heerschap

引用次数: 46

Analytical Solutions and Simulations for Spin-Echo Measurements of Diffusion of Spins in a Sphere with Surface and Bulk Relaxation 具有表面松弛和体积松弛的球体中自旋扩散的自旋回波测量的解析解和模拟

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0103

Philip W. Kuchel , Alison J. Lennon , Christopher Durrant

{"title":"Analytical Solutions and Simulations for Spin-Echo Measurements of Diffusion of Spins in a Sphere with Surface and Bulk Relaxation","authors":"Philip W. Kuchel , Alison J. Lennon , Christopher Durrant","doi":"10.1006/jmrb.1996.0103","DOIUrl":"10.1006/jmrb.1996.0103","url":null,"abstract":"<div><p>Nuclear spins (in molecules) are considered to be diffusing in a sphere in a linearly inhomogeneous magnetic field (field gradient) that is imposed during a spin-echo NMR experiment. Relaxation of magnetization both in the bulk medium and on the inner surface of the sphere is assumed to occur. Analytical solutions were obtained for the relevant modified diffusion (partial differential) equation by using separation of variables with a Green's function (propagator) and three different boundary conditions. Neuman [<em>J. Chem. Phys.</em>60, 4508 (1974)] analyzed the same physical system, but with no relaxation, to obtain an expression that relates the NMR spin-echo signal intensity to the magnitude of the magnetic field gradient, the spin-echo time, and the intrinsic molecular diffusion coefficient. The present analysis was based on that originally used by Neuman and, like the latter, it employed the assumption of a Gaussian distribution of phases of the spin magnetizations. This assumption, while rendering a tractable solution, nevertheless limits its range of applicability; this aspect, and the convergence properties of the series solutions were investigated in conjunction with numerical simulations made with diffusion modeled as a three-dimensional random (Monte Carlo) walk. A novel prediction for spheres with finite surface relaxation and a given radius is the presence of two minima in a graph of the normalized spin-echo signal intensity versus the reciprocal of the diffusion coefficient.</p></div>","PeriodicalId":16130,"journal":{"name":"Journal of Magnetic Resonance, Series B","volume":"112 1","pages":"Pages 1-17"},"PeriodicalIF":0.0,"publicationDate":"1996-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/jmrb.1996.0103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19638175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 32

NMR Spectral Quantitation by Principal-Component Analysis. II. Determination of Frequency and Phase Shifts 主成分分析的核磁共振光谱定量。二世。频率和相移的测定

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0106

Truman R. Brown , Radka Stoyanova

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引用次数: 77

A Potential Involving Multiple Proton Chemical-Shift Restraints for Nonstereospecifically Assigned Methyl and Methylene Protons 非立体定向分配的甲基和亚甲基质子涉及多质子化学位移约束的潜力

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0113

John Kuszewski, Angela M. Gronenborn , G.Marius Clore

引用次数: 21

Fast Magnetic-Resonance Temperature Imaging 快速磁共振温度成像

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0115

Jacco A. de Zwart, Peter van Gelderen, Dan J. Kelly, Chrit T.W. Moonen

引用次数: 66

Two-Dimensional NMR Study of a Liquid-Crystal Solution under Magic-Angle Spinning. Conformation of Carboxylic Ionophore Lasalocid A Dissolved in a Lyotropic Liquid Crystal 魔角旋转下液晶溶液的二维核磁共振研究。羧基离子泛lasalacid A在溶变液晶中的构象

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0107

Atsuomi Kimura , Tetsushi Kano, Hideaki Fujiwara

引用次数: 2

Cation-Binding Location and Hydrogen-Exchange Sites for Gramicidin in SDS Micelles Using NOESY NMR 用NOESY核磁共振研究革兰西菌素在SDS胶束中的阳离子结合定位和氢交换位点

Journal of Magnetic Resonance, Series B Pub Date : 1996-07-01 DOI: 10.1006/jmrb.1996.0105

J.F. Hinton

引用次数: 6

Multiple-π-Pulse Sequences in Biological Solid-State NMR. Enhancement of Sensitivity by Permutation of the Phases 生物固体核磁共振多π脉冲序列。通过相位排列提高灵敏度

Journal of Magnetic Resonance, Series B Pub Date : 1996-06-01 DOI: 10.1006/jmrb.1996.0097

Yan Li, Jeremy N.S. Evans

引用次数: 1

Maximizing Signal-to-Noise Ratio in the Presence of Coil Coupling 在线圈耦合存在下最大化信噪比

Journal of Magnetic Resonance, Series B Pub Date : 1996-06-01 DOI: 10.1006/jmrb.1996.0088

G.R. Duensing , H.R. Brooker , J.R. Fitzsimmons

引用次数: 55