Impulsions Sélectives Et Leurs Applications en Spectroscopie Et en Imagerie de Résonance Magnétique Nucléaire PDF Download

Author: Lyndon Emsley
Publisher:
ISBN:
Category :
Languages : en
Pages : 177

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Author: Jean-Louis Lefevre
Publisher:
ISBN:
Category :
Languages : fr
Pages : 244

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RAPPEL DES PRINCIPES DE L'IMAGERIE PAR RMN. ON PRESENTE ENSUITE LES RESULTATS D'UNE ETUDE DE LA SELECTIVITE D'IMPULSIONS RADIOFREQUENCES MODULEES EN AMPLITUDE. CETTE ETUDE A ETE CONDUITE PAR RESOLUTION NUMERIQUE DES EQUATIONS DE BLOCH ET A PERMIS DE COMPARER L'EFFET SELECTIF DE DIVERSES FORMES DE MODULATION. REALISATION DE DIVERS APPAREILLAGES : SEQUENCEUR DES COURANTS DE GRADIENT DE CHAMP MAGNETIQUE, CARTE MEMOIRE DE LA FORME D'ONDE, MODULATEUR DE PUISSANCE

Author: Patrick Le Roux
Publisher:
ISBN:
Category :
Languages : en
Pages : 164

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Regular RF pulse trains used in NMR can be studied with simple algorithms of polynomial type using the Z transform. Another simplification is brought by the use of spinors to model the rotations. The first application presented is a ‘peel-off' algorithm which permits the synthesis of selective radiofrequency pulses as the ones used in MRI. This algorithm makes the non linearity of the Bloch equations easy to handle. Some unpublished implementation details are given along with some theoretical results concerning the convergence of the hard pulse train approximation and the prediction of the energy deposition. The same tools are subsequently used to obtain a simplified model of the CPMG and SSFP sequences. The echo to echo rotation is studied and the natural stabilization of the signals is explained by the dispersion of phase. The relaxation processes during such sequences are also modelled in a simplified but widely applicable manner. A previous polynomials stabilization algorithm is explained in terms of a discrete version of the adiabatic principle. The last chapter tackles with a non-CPMG sequence which is insensitive to the initial phase of the magnetization. This sequence is based on a quadratic phase modulation of the RF pulse train.

Author: Ahmed Belasri
Publisher: Springer Nature
ISBN: 9811554447
Category : Technology & Engineering
Languages : en
Pages : 659

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This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.

Author: Agnes Buka
Publisher: World Scientific
ISBN: 1848167997
Category : Science
Languages : en
Pages : 299

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The book intends to give a state-of-the-art overview of flexoelectricity, a linear physical coupling between mechanical (orientational) deformations and electric polarization, which is specific to systems with orientational order, such as liquid crystals. Chapters written by experts in the field shed light on theoretical as well as experimental aspects of research carried out since the discovery of flexoelectricity. Besides a common macroscopic (continuum) description the microscopic theory of flexoelectricity is also addressed. Electro-optic effects due to or modified by flexoelectricity as well as various (direct and indirect) measurement methods are discussed. Special emphasis is given to the role of flexoelectricity in pattern-forming instabilities. While the main focus of the book lies in flexoelectricity in nematic liquid crystals, peculiarities of other mesophases (bent-core systems, cholesterics, and smectics) are also reviewed. Flexoelectricity has relevance to biological (living) systems and can also offer possibilities for technical applications. The basics of these two interdisciplinary fields are also summarized.

Author: Jean Daillant
Publisher: Springer Science & Business Media
ISBN: 3540486968
Category : Science
Languages : en
Pages : 347

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The reflection of and neutrons from surfaces has existed as an x-rays exp- imental for almost it is in the last technique fifty Nevertheless, only years. decade that these methods have become as of enormously popular probes This the surfaces and interfaces. to be due to of several appears convergence of intense different circumstances. These include the more n- availability be measured orders tron and sources that can over (so reflectivity x-ray many of and the much weaker surface diffuse can now also be magnitude scattering of thin films and studied in some the detail); growing importance multil- basic the realization of the ers in both and technology research; important which in the of surfaces and and role roughness plays properties interfaces; the of statistical models to characterize the of finally development topology its and its characterization from on roughness, dependence growth processes The of and to surface scattering experiments. ability x-rays neutro4s study four five orders of in scale of surfaces over to magnitude length regardless their and also their to ability probe environment, temperature, pressure, etc. , makes these the choice for buried interfaces often probes preferred obtaining information about the microstructure of often in statistical a global surfaces, the local This is manner to complementary imaging microscopy techniques, of such studies in the literature witnessed the veritable by explosion published the last few Thus these lectures will useful for over a resource years.

Author: Michael L. J. Apuzzo
Publisher: Thieme
ISBN: 9781879284319
Category : Medical
Languages : en
Pages : 262

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Book Description
Benign Cerebral Glioma, Volume I is a valuable text which looks at the rapidly expanding, multidisciplinary body of knowledge about the development, molecular biology, molecular genetic and pathology of human cerebral gliomas. This generously illustrated text is written and edited by recognized experts in the field. Volume I includes topics such as: The developmental biology of glial cells and its relation to the study of glioma biology The pathology of benign cerebral astrocytomas, oligodendrogliomas, benigh ependymomas and ganglion cell tumors Patterns of tumor growth and problems associated with histological typing of low-grad gliomas Growth factors and proliferation potential Malignant progression in gliomas (Distributed by Thieme for the American Association of Neurological Surgeons)

Author: I. Bezverkhyy
Publisher:
ISBN: 9783037853979
Category : Diffusion
Languages : en
Pages : 0

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Book Description
The International Conference on Diffusion in Materials (DIMAT) is the benchmark conference series for diffusion in solids. DIMAT 2011 was organized by the University of Bourgogne in association with CNRS, Dijon (France). The conference showcased new results concerning theoretical tools as well as applied research approaches. Diffusion processes affect all types of materials: nanomaterials, materials for energy, metallurgy, glasses and ceramics, but each requires its own numerical tools.Volume is indexed by Thomson Reuters CPCI-S (WoS). This volume comprises most of the contributions presented at DIMAT 2011: 4 plenary lectures delivered by famous high-level scientists plus 88 contributions in the form of keynote lectures, talks and posters.

Author: Canada. Patent Office
Publisher:
ISBN:
Category : Copyright
Languages : en
Pages : 1070

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Author: Jerome V. Moloney
Publisher: Springer Science & Business Media
ISBN: 9780387985817
Category : Business & Economics
Languages : en
Pages : 270

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Mathematical methods play a significant role in the rapidly growing field of nonlinear optical materials. This volume discusses a number of successful or promising contributions. The overall theme of this volume is twofold: (1) the challenges faced in computing and optimizing nonlinear optical material properties; and (2) the exploitation of these properties in important areas of application. These include the design of optical amplifiers and lasers, as well as novel optical switches. Research topics in this volume include how to exploit the magnetooptic effect, how to work with the nonlinear optical response of materials, how to predict laser-induced breakdown in efficient optical devices, and how to handle electron cloud distortion in femtosecond processes.