Download or read book Chemically Induced Dynamic Nuclear and Electron Polarizations CIDNP and CIDEP written by C. Richard and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anomalous electron-spin state populations in the Electron Paramagnetic Re sonance (EPR) spectra of radicals formed during radio lysis experiments were observed in 1963 by FESSENDEN and SCHULER [170a]. This phenomenon did not receive much attention at the time. In 1967, BARGON, FISCHER, and JOHNSEN [5] and independently WARD and LAWLER [7,8] reported a similar phenomenon for Nuclear Magnetic Resonance (NMR) spectra taken during radical reactions: emission or enhanced absorption, or both. The earliest attempts to explain this new NMR phenomenon treated these effects in a way similar to that of Dynamic Nuclear Polarization (DNP) or the Overhauser effect. Although the polarization has a completely different origin, DNP gave its name to this effect: Chemically Induced Dynamic Nuclear Polariza tion (CIDNP). [The name Chemically Induced Dynamic Electron Polarization (CIDEP) was introduced later by analogy with CIDNP]. After the initial publica tions, all the new data demonstrated that the first theory could not be correct. In 1969, a new theory was proposed by CLOSS [18] and independently by KAPTEIN and OOSTERHOFF [23] and called the radical-pair theory. This mechanism was proposed to account for the observations of polarization in both NMR and EPR. The radical-pair theory is based on weak interactions in a pair of radicals: the strength of interaction between the electronic states of the radicals depends in particular on the nuclear-spin states.

Download or read book XXIIIrd International Congress of Pure and Applied Chemistry written by Sam Stuart and published by Elsevier. This book was released on 2013-09-17 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: XXIIIrd International Congress of Pure and Applied Chemistry, Volume 4 contains papers presented at the XXIIIrd International Congress of Pure and Applied Chemistry held in Boston, USA on July 26-30, 1971. This book is organized into two main topics—short-lived intermediates, free radicals and homolytic mechanisms, and ion pair processes. This publication specifically discusses the chemically induced dynamic nuclear polarization, formation of radical anions by the attack of radicals upon anions, and high temperature organic reactions by flash vacuum pyrolysis. The structure-reactivity relationships in the chemistry of aliphatic free radicals, medium effects on radical-radical reactions, and oxidation of alkyl radicals by metal complexes are also described. This text likewise considers the end group association and complexation in anionic polymerization and reversal of singlet and triplet states in aromatic dianions with trigonal symmetry. This compilation is useful to chemists and specialists researching on pure and applied chemistry.

Download or read book American Doctoral Dissertations written by and published by . This book was released on 1980 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hyperpolarization Methods in NMR Spectroscopy written by Lars T. Kuhn and published by Springer. This book was released on 2013-09-13 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elucidating Organic Reaction Mechanisms using photo-CIDNP Spectroscopy, by Martin Goez. Parahydrogen Induced Polarization by Homogeneous Catalysis: Theory and Applications, by Kerstin Münnemann et al. Improving NMR and MRI Sensitivity with Parahydrogen, by R. Mewis & Simon Duckett. The Solid-state Photo-CIDNP Effect, by Jörg Matysik et al. Parahydrogen-induced Polarization in Heterogeneous Catalytic Processes, by Igor Koptyug et al. Dynamic Nuclear Polarization Enhanced NMR Spectroscopy, by U. Akbey & H. Oschkinat. Photo-CIDNP NMR Spectroscopy of Amino Acids and Proteins, by Lars T. Kuhn.

Download or read book The Chemist s Companion written by Arnold J. Gordon and published by John Wiley & Sons. This book was released on 1973-01-19 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here in one source is a wide variety of practical, everydayinformation often required by chemists but seldom found together,if at all, in the standard handbooks, data collections, manuals,and other usual sources. Discussing physical, chemical, andmechanical properties of substances and systems, the authors answersuch questions as: * How do I test for and destroy peroxides in different solventsand what is the best way to purify such solvents? * What are the structure, physical properties, and recentreferences to the use of common-name solvents and solvent aids suchas the "Skellysolves," "Cellosolves," "Crownanes," and"Glymes"? * What is the utility of a particular molecular sieve, orpermeation gel, or epoxy cement, or liquid crystal, and where do Ibuy them and find references to their application? The book is divided into nine chapters and covers properties ofatoms and molecules, spectroscopy, photochemistry, chromatography,kinetics and thermodynamics, various experimental techniques, andmathematical and numerical information, including the definitions,values, and usage rules of the newly adopted International Systemof Units (SI Units). A section on statistical treatment of datawhich provides an actual least-squares computer program is alsoincluded. In the spectroscopy chapter, very extensive andup-to-date collections of spectral correlation data are presentedfor ir, uv-vis, optical rotation, nmr, and mass spectra, along withdata on esr and nqr spectroscopy. Also included is a variety ofhard-to-classify but frequently sought information, such as namesand addresses of microanalysis companies and chemistry publishers,descriptions and commercial sources of atomic and molecular models,and safety data for hazardous chemicals. More than 500 keyreferences are also included, most of which are recent. There areimportant hints and definitions associated with the art as well asthe state of the art for the appropriate subjects. Also foundthroughout the book are about 250 suppliers and directions forobtaining special booklets or other material. Containing a wealth of useful information, The Chemist'sCompanion will be an indispensable guide for students andprofessional chemists in nearly all the chemical disciplines. Inaddition, it will provide for the teacher and student an unusualadjunct for use in a broad cross-section of chemistry courses.

Download or read book Modern NMR Methodology written by Henrike Heise and published by Springer. This book was released on 2014-07-08 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: NMR Spectroscopy for Chemical Analysis at Low Magnetic Fields, by Stefan Glöggler, Bernhard Blümich, Stephan Appelt Dynamic Nuclear Hyperpolarization in Liquids, by Ulrich L. Günther NMR with Multiple Receivers, by Eriks Kupce TROSY NMR Spectroscopy of Large Soluble Proteins, by Yingqi Xu, Stephen Matthews Solid-State NMR Spectroscopy of Proteins, by Henrik Müller, Manuel Etzkorn, Henrike Heise Paramagnetic Solid-State Magic-Angle Spinning NMR Spectroscopy, by Guido Pintacuda, Gwendal Kervern

Download or read book Faculties Publications and Doctoral Theses in Chemistry and Chemical Engineering at United States Universities written by American Chemical Society. Committee on Professional Training and published by . This book was released on 1991 with total page 1646 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Compact NMR written by Bernhard Blümich and published by Walter de Gruyter GmbH & Co KG. This book was released on 2014-08-22 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this book is to provide an introduction to the practical use of mobile NMR at a level as basic as the operation of a smart phone. Each description follows the same didactic pattern: introduction, basic theory, pulse sequences and parameters, beginners-level measurements, advanced-level measurements, and data processing. Nuclear Magnetic Resonance (NMR) spectroscopy is the most popular method for chemists to analyze molecular structures while Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic tool for medical doctors that provides high-contrast images of biological tissue depicting the brain function and the beating heart. In both applications large super-conducting magnets are employed which magnetize atomic nuclei of an object positioned inside the magnet. Their circulating motion is interrogated by radio-frequency waves. Depending on the operating mode, the frequency spectrum provides the chemist with molecular information, the medical doctor with anatomic images, while the materials scientist is interested in NMR relaxation parameters, which scale with material properties and determine the contrast in magnetic resonance images. Recent advances in magnet technology led to a variety of small permanent magnets, by which NMR spectra, images, and relaxation parameters can be measured with mobile and low-cost instruments.

Download or read book Annual Reports on NMR Spectroscopy written by and published by Academic Press. This book was released on 1993-01-26 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annual Reports on NMR Spectroscopy

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1984 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NMR Spectroscopy written by Harald Günther and published by John Wiley & Sons. This book was released on 2013-12-13 with total page 842 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear magnetic resonance (NMR) spectroscopy is one of the most powerful and widely used techniques in chemical research for investigating structures and dynamics of molecules. Advanced methods can even be utilized for structure determinations of biopolymers, for example proteins or nucleic acids. NMR is also used in medicine for magnetic resonance imaging (MRI). The method is based on spectral lines of different atomic nuclei that are excited when a strong magnetic field and a radiofrequency transmitter are applied. The method is very sensitive to the features of molecular structure because also the neighboring atoms influence the signals from individual nuclei and this is important for determining the 3D-structure of molecules. This new edition of the popular classic has a clear style and a highly practical, mostly non-mathematical approach. Many examples are taken from organic and organometallic chemistry, making this book an invaluable guide to undergraduate and graduate students of organic chemistry, biochemistry, spectroscopy or physical chemistry, and to researchers using this well-established and extremely important technique. Problems and solutions are included.

Download or read book Advances in Physical Organic Chemistry written by John P. Richard and published by Gulf Professional Publishing. This book was released on 2002-12-31 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Physical Organic Chemistry provides the chemical community with authoritative and critical assessments of the many aspects of physical organic chemistry. The field is a fast developing one, with results and methodologies finding application from biology to solid state physics. This latest volume deals comprehensively with investigations that can be traced back to the birth of the field but which are still proving critical to the understanding of the stability of organic molecules and the mechanisms for their reactions. Volume 37 of this hugely successful Advances in Physical Organic Chemistry series Comprehensive review articles covering various topics of interest within the physical organic chemistry field

Download or read book Multifrequency Electron Paramagnetic Resonance written by Sushil K. Misra and published by John Wiley & Sons. This book was released on 2011-03-31 with total page 990 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filling the gap for a systematic, authoritative, and up-to-date review of this cutting-edge technique, this book covers both low and high frequency EPR, emphasizing the importance of adopting the multifrequency approach to study paramagnetic systems in full detail by using the EPR method. In so doing, it discusses not only the underlying theory and applications, but also all recent advances -- with a final section devoted to future perspectives.

Download or read book Protein Dynamics Function and Design written by Oleg Jardetzky and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is a collection of articles from the proceedings of the International School of Structural Biology and Magnetic Resonance 3rd Course: Protein Dynamics, Function, and Design. This NATO Advance Study Institute was held in Erice at the Ettore Majorana Centre for Scientific Culture on April 16-28, 1997. The aim of the Institute was to bring together experts applyipg different physical methods to problems of macro molecular dynamics-notably x-ray diffraction, NMR and other forms of spectroscopy, and molecular dynamics simulations. Emphasis was placed on those systems and types of problems-such as mechanisms of allosteric control, signal transmission, induced fit to different ligands with its implications for drug design, and the effects of dynamics on structure determination-where a correlation of findings obtained by different methods could shed the most light on the mechanisms involved and stimulate the search for new approaches. The individual articles represent the state of the art in each of the areas cov ered and provide a guide to the original literature in this rapidly developing field. v CONTENTS 1. Determining Structures of ProteinlDN A Complexes by NMR Angela M. Gronenbom and G. Marius Clore 2. Fitting Protein Structures to Experimental Data: Lessons from before Your Mother Was Born . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Jeffrey C. Hoch, Alan S. Stem, and Peter J. Connolly 3. Multisubunit Allosteric Proteins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 William N. Lipscomb 4. Studying Protein Structure and Function by Directed Evolution: Examples with Engineered Antibodies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Andreas Pliickthun 5. High Pressure Effects on Protein Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Download or read book Cumulated Index Medicus written by and published by . This book was released on 1999 with total page 1860 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summaries of Projects Completed in Fiscal Year written by and published by . This book was released on 1979 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summaries of Projects Completed written by National Science Foundation (U.S.) and published by . This book was released on with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt: