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Reference deconvolution: a simple and effective method for resolution enhancement in nuclear magnetic resonance spectroscopy 参考反褶积:一种简单有效的提高核磁共振波谱分辨率的方法
Concepts in magnetic resonance Pub Date : 2000-03-01 DOI: 10.1002/(SICI)1099-0534(2000)12:1<21::AID-CMR4>3.3.CO;2-I
K. Metz, M. M. Lam, A. Webb
{"title":"Reference deconvolution: a simple and effective method for resolution enhancement in nuclear magnetic resonance spectroscopy","authors":"K. Metz, M. M. Lam, A. Webb","doi":"10.1002/(SICI)1099-0534(2000)12:1<21::AID-CMR4>3.3.CO;2-I","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(2000)12:1<21::AID-CMR4>3.3.CO;2-I","url":null,"abstract":"Linewidths and line shapes are key criteria determining the utility of a nuclear magnetic resonance (NMR) spectrum, and considerable effort is usually devoted to shimming the magnetic field (B0) to ensure optimum resolution. However, even if the external field is almost perfectly homogeneous, the sample itself can induce gradients owing to susceptibility effects from its overall shape or internal heterogeneity. Thus, magnetic field gradients nearly always contribute significantly to the linewidths and shapes in an NMR spectrum. Reference deconvolution is a technique which uses the shape of a single resonance line to measure the actual frequency distribution produced by the local B0 inhomogeneity and then deconvolves that distribution from the whole spectrum. It is a simple linear process which requires no prior knowledge of the number of lines, their intensities, or their relaxation characteristics. No fitting procedures are used. This article reviews the reference deconvolution method, demonstrates its application to one-dimensional NMR spectroscopy, and discusses the tradeoffs between resolution and signal/noise. ©2000 John Wiley & Sons, Inc. Concepts Magn Reson 12: 21–42, 2000","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"25 4","pages":"21-42"},"PeriodicalIF":0.0,"publicationDate":"2000-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50682411","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: 66
Hartmann-Hahn polarization transfer in liquids: An ideal tool for selective experiments 液体中的哈特曼-哈恩极化传递:一种理想的选择性实验工具
Concepts in magnetic resonance Pub Date : 2000-01-01 DOI: 10.1002/(SICI)1099-0534(2000)12:3<103::AID-CMR1>3.0.CO;2-#
P. Pelupessy, E. Chiarparin
{"title":"Hartmann-Hahn polarization transfer in liquids: An ideal tool for selective experiments","authors":"P. Pelupessy, E. Chiarparin","doi":"10.1002/(SICI)1099-0534(2000)12:3<103::AID-CMR1>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(2000)12:3<103::AID-CMR1>3.0.CO;2-#","url":null,"abstract":"Cross-polarization using continuous-wave spin-locking fields has never become routine in liquid-state nuclear magnetic resonance. Efficiency of cross-polarization tends to be strongly attenuated if radio-frequency (RF) fields are not perfectly homogeneous. It has recently been demonstrated that imperfections in RF-fields have little effect on efficiency of polarization transfer, provided that RF-amplitudes are comparable to magnitudes of heteronuclear scalar coupling constants, rendering this method ideal for selective experiments. The technique can be exploited for the excitation of nuclei with a low gyromagnetic factor like 13C and 15N, as well as of nuclei with a high gyromagnetic factor like 1H. Several useful applications are discussed. © 2000 John Wiley & Sons, Inc. Concepts Magn Reson 12: 103–124, 2000","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"281 1","pages":"103-124"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1099-0534(2000)12:3<103::AID-CMR1>3.0.CO;2-#","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50683254","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: 56
Interplay among recovery time, signal, and noise: series- and parallel-tuned circuits are not always the same 恢复时间、信号和噪声之间的相互作用:串联和并联调谐电路并不总是相同的
Concepts in magnetic resonance Pub Date : 2000-01-01 DOI: 10.1002/(SICI)1099-0534(2000)12:3<125::AID-CMR2>3.3.CO;2-G
Joel B. Miller, B. Suits, A. N. Garroway, M. Hepp
{"title":"Interplay among recovery time, signal, and noise: series- and parallel-tuned circuits are not always the same","authors":"Joel B. Miller, B. Suits, A. N. Garroway, M. Hepp","doi":"10.1002/(SICI)1099-0534(2000)12:3<125::AID-CMR2>3.3.CO;2-G","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(2000)12:3<125::AID-CMR2>3.3.CO;2-G","url":null,"abstract":"The quality factor, Q, of the magnetic resonance probe and the manner in which the probe is coupled to the spectrometer play important roles in the quality of the obtained experimental data, affecting the signal-to-noise ratio (SNR), the probe recovery time, radiation-damping, and the coupling between multiple coils. For example, high SNR often requires a high-Q probe, while a short recovery time to observe of broad signals generally requires low Q. Here, we discuss effecting a compromise between SNR and recovery time by adjusting the coupling of the probe and preamplifier by mismatching their impedances. Unlike the more common impedance-matched case, the conditions for optimum performance for parallel- and series-tuned probes are found to differ significantly. © 2000 John Wiley & Sons, Inc. Concepts Magn Reson 12: 125–136, 2000","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"277 6","pages":"125-136"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50683297","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: 18
Average Liouvillian theory in nuclear magnetic resonance—principles, properties, and applications 核磁共振中的平均刘维廉理论——原理、性质和应用
Concepts in magnetic resonance Pub Date : 2000-01-01 DOI: 10.1002/(SICI)1099-0534(2000)12:3<152::AID-CMR4>3.3.CO;2-G
R. Ghose
{"title":"Average Liouvillian theory in nuclear magnetic resonance—principles, properties, and applications","authors":"R. Ghose","doi":"10.1002/(SICI)1099-0534(2000)12:3<152::AID-CMR4>3.3.CO;2-G","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(2000)12:3<152::AID-CMR4>3.3.CO;2-G","url":null,"abstract":"The transient as well as the long-term behavior of the spin-density operator under the influence of radiofrequency pulses and periods of free-precession can be predicted to a reasonable degree of accuracy within the framework of the Average Liouvillian Theory. This approach can be used to design pulse sequences which suppress the effects of certain components of the Liouvillian on the spin dynamics while allowing the detailed analysis of the effects of others. We present here the basic principles of Average Liouvillian Theory and its application in the design of pulse sequences to study the structural and dynamic properties of biomolecules. © 2000 John Wiley & Sons, Inc. Concepts Magn Reson 12: 152–172, 2000","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"266 1","pages":"152-172"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50682925","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: 24
Simulation of in-plane flow imaging 平面内流成像仿真
Concepts in magnetic resonance Pub Date : 1999-11-01 DOI: 10.1002/(SICI)1099-0534(1999)11:6<379::AID-CMR3>3.3.CO;2-G
I. Marshall
{"title":"Simulation of in-plane flow imaging","authors":"I. Marshall","doi":"10.1002/(SICI)1099-0534(1999)11:6<379::AID-CMR3>3.3.CO;2-G","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(1999)11:6<379::AID-CMR3>3.3.CO;2-G","url":null,"abstract":"Two methods of simulating the imaging process in magnetic resonance (MR) are explained: namely, the k-space and the isochromat summation methods. The latter method is more closely related to the actual behavior of magnetic spins, and is used in the remainder of this work. The MR image appearance of in-plane fluid flow is simulated using the isochromat summation technique. Flow-related artifacts are demonstrated, together with flow compensation, phase-contrast (PC) velocity encoding, and cine-PC measurement of pulsatile flow. The special considerations necessary for simulating pulsatile flow with a reverse flow component are discussed. Magnetic field inhomogeneities and susceptibility effects are readily incorporated. The computation time required for the simulations is discussed in some detail. Simulations of flow imaging have been found useful in the development and validation of new pulse sequences, and for teaching purposes. ©1999 John Wiley & Sons, Inc. Concepts Magn Reson 11: 379–392, 1999","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"7 3","pages":"379-392"},"PeriodicalIF":0.0,"publicationDate":"1999-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50682060","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: 13
Magnetic resonance imaging in a hands-on student experiment using an EPR spectrometer 磁共振成像在学生实验中使用EPR光谱仪
Concepts in magnetic resonance Pub Date : 1999-09-01 DOI: 10.1002/(SICI)1099-0534(1999)11:5<277::AID-CMR1>3.3.CO;2-Y
A. Smirnov, R. Belford, Reef Morse
{"title":"Magnetic resonance imaging in a hands-on student experiment using an EPR spectrometer","authors":"A. Smirnov, R. Belford, Reef Morse","doi":"10.1002/(SICI)1099-0534(1999)11:5<277::AID-CMR1>3.3.CO;2-Y","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(1999)11:5<277::AID-CMR1>3.3.CO;2-Y","url":null,"abstract":"","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"76 8","pages":"277-290"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50682123","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: 4
Using injectable carriers of laser-polarized noble gases for enhancing NMR and MRI 利用激光极化惰性气体的可注射载体增强核磁共振和核磁共振
Concepts in magnetic resonance Pub Date : 1999-06-01 DOI: 10.1002/(SICI)1099-0534(1999)11:4<203::AID-CMR2>3.3.CO;2-G
B. Goodson
{"title":"Using injectable carriers of laser-polarized noble gases for enhancing NMR and MRI","authors":"B. Goodson","doi":"10.1002/(SICI)1099-0534(1999)11:4<203::AID-CMR2>3.3.CO;2-G","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(1999)11:4<203::AID-CMR2>3.3.CO;2-G","url":null,"abstract":"Laser-polarized noble gases hold enormous potential for enhancing sensitivity and contrast for a variety of nuclear magnetic resonance and magnetic resonance imaging experiments. Potential biomedical applications are especially tantalizing; however, overcoming the difficulty of delivering laser-polarized noble gases to living tissues with sufficient polarization and concentration may be critical to the feasibility of many proposed in vivo studies. One suggested means of delivering laser-polarized noble gases to tissues involves the local injection of biologically compatible solutions in which high noble gas concentrations and long polarization lifetimes can be achieved. In this review, the general topic of biomedical applications of laser-polarized noble gases is introduced. Special attention is given to a description of the injection technique and its applications, along with a discussion of potential advantages and limitations. Concluding remarks discuss the future outlook for biomedical applications of laser-polarized noble gases in general, particularly in light of recent low-field magnetic resonance experiments. ©1999 John Wiley & Sons, Inc. Concepts Magn Reson 11: 203–223, 1999","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"8 1","pages":"203-223"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50681747","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: 30
Precession and Sir Joseph Larmor 和约瑟夫·拉莫尔爵士
Concepts in magnetic resonance Pub Date : 1999-06-01 DOI: 10.1002/(SICI)1099-0534(1999)11:4<239::AID-CMR4>3.3.CO;2-Q
M. Meadows
{"title":"Precession and Sir Joseph Larmor","authors":"M. Meadows","doi":"10.1002/(SICI)1099-0534(1999)11:4<239::AID-CMR4>3.3.CO;2-Q","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(1999)11:4<239::AID-CMR4>3.3.CO;2-Q","url":null,"abstract":"","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"84 7","pages":"239-241"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50681475","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: 2
Methods of measuring spin-lattice ( T 1 ) relaxation times: an annotated bibliography 测量自旋晶格(t1)弛豫时间的方法:有注释的参考书目
Concepts in magnetic resonance Pub Date : 1999-06-01 DOI: 10.1002/(SICI)1099-0534(1999)11:4<243::AID-CMR5>3.3.CO;2-3
P. Kingsley
{"title":"Methods of measuring spin-lattice ( T 1 ) relaxation times: an annotated bibliography","authors":"P. Kingsley","doi":"10.1002/(SICI)1099-0534(1999)11:4<243::AID-CMR5>3.3.CO;2-3","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(1999)11:4<243::AID-CMR5>3.3.CO;2-3","url":null,"abstract":"This review of methods of measuring spin-lattice (T1) relaxation times comprises 283 references, including 90 references on magnetic resonance imaging. Annotations give brief descriptions of each reference. References are organized by major categories, with cross-references to other topics. Major categories include many methods, optimization, data analysis, elimination of errors, signal intensity formulas, chemical exchange, and spatially localized measurements. Key references are indicated in several categories. ©1999 John Wiley & Sons, Inc. Concepts Magn Reson 11: 243–276, 1999","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"78 s1","pages":"243-276"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50681628","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: 90
Observations of quantum dynamics by solution-state NMR spectroscopy 用溶液态核磁共振光谱法观察量子动力学
Concepts in magnetic resonance Pub Date : 1999-05-20 DOI: 10.1002/(SICI)1099-0534(1999)11:4<225::AID-CMR3>3.3.CO;2-5
M. Pravia, E. Fortunato, Y. Weinstein, M. Price, G. Teklemariam, R. J. Nelson, Y. Sharf, S. Somaroo, C. Tseng, Timothy F. Havel, D. Cory
{"title":"Observations of quantum dynamics by solution-state NMR spectroscopy","authors":"M. Pravia, E. Fortunato, Y. Weinstein, M. Price, G. Teklemariam, R. J. Nelson, Y. Sharf, S. Somaroo, C. Tseng, Timothy F. Havel, D. Cory","doi":"10.1002/(SICI)1099-0534(1999)11:4<225::AID-CMR3>3.3.CO;2-5","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0534(1999)11:4<225::AID-CMR3>3.3.CO;2-5","url":null,"abstract":"NMR is emerging as a valuable testbed for the investigation of foundational questions in quantum mechanics. The present article outlines the preparation of a class of mixed states, called pseudo-pure states, that emulate pure quantum states in highly mixed solution-state NMR samples. It also describes the NMR observation of spinor behavior in spin ½ nuclei, the simulation of wave function collapse using a magnetic field gradient, the creation of entangled (i.e., Bell) pseudo-pure states, and a brief discussion of quantum computing logic gates including the Quantum Fourier Transform. These experiments show that solution-state NMR can be used to demonstrate quantum dynamics at a level suitable for laboratory exercises. ©1999 John Wiley & Sons, Inc. Concepts Magn Reson 11: 225–238, 1999","PeriodicalId":89665,"journal":{"name":"Concepts in magnetic resonance","volume":"9 2","pages":"225-238"},"PeriodicalIF":0.0,"publicationDate":"1999-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50681395","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: 17
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