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Publications associées (529)

Selective two-dimensional NMR experiments for topological filtration of fragments of coupling networks

David Lyndon Emsley, Geoffrey Bodenhausen

In high-resoln. NMR, a network of scalar-coupled spins can be broken down into fragments which encode information about the chem. shifts and couplings that are relevant to a cross-peak multiplet in a two-dimensional correlation ("COSY") expt. Novel selec ...

1991

Ion-Cyclotron Wave Excitation by Double-Resonance Coupling

Ambrogio Fasoli, Minh Quang Tran

A modulated high frequency wave is used to remotely excite low frequency oscillations in a linear, strongly magnetized plasma column. An electromagnetic wave is launched as an extraordinary mode across the plasma by an external waveguide in the upper-hybri ...

1991

Unraveling overlapping multiplets in two-dimensional NMR spectra by selective injection of coherence

Geoffrey Bodenhausen

In order to sep. overlapping diagonal multiplets in two- or three-dimensional NMR spectra, new sequences using selective pulses are described which allow one to "inject" magnetization at the beginning of the evolution period by transfer from a selected cou ...

1991

Entflechtung überlagernder Multipletts in zweidimensionalen NMR‐Korrelationsspektren durch selektive Inversion der Spins der Kopplungspartner

David Lyndon Emsley, Geoffrey Bodenhausen

A new method called selective inversion soft COSY (SIS-COSY) is described. By using this method the coupling between active and passive spins can be detected. The pulse sequence consists of 3 semiselective 270 Deg pulses, which gives a spectrum consisting ...

1990

Non-invasive 31P magnetic resonance spectroscopy revealed McArdle disease in an asymptomatic child

Rolf Gruetter

A Turkish couple suffering from McArdle disease (myophosphorylase deficiency) and their two sons aged 5 and 9 years, respectively, were studied using 31phosphorus magnetic resonance spectroscopy (31P MRS). During exercise both sons showed the same patholog ...

1990

Frequency-modulated "chirp" pulses for broadband inversion recovery in magnetic resonance

Geoffrey Bodenhausen, Martial Rey

A novel approach to inversion recovery in NMR is described which combines adiabatic inversion with the observation of a spin echo refocused by a chirp pulse. This echo method allows one to generate in-phase magnetization over a broad range of frequencies. ...

1990

Measurement of transverse relaxation in coupled spin systems by semi-selective refocusing: evidence for interference of CSA and dipolar relaxation

David Lyndon Emsley, Geoffrey Bodenhausen

A novel spin-echo expt. is proposed that uses semiselective Gaussian pulse cascades for refocusing in systems with homonuclear couplings. The expt. allows one to obtain evdience of differential T2 effects due to cross-correlation of proton chem. shift anis ...

1990

Automated analysis of two-dimensional correlation spectra: assembly of fragments into networks of coupled spins

Geoffrey Bodenhausen

The fine structures of multiplets in 2-dimensional correlation spectra arise from coherence transfer processes that can be rationalized in terms of connectivity diagrams. These can be derived from conventional energy-level diagrams, which in turn reflect t ...

1990

Broadband multiple-quantum nuclear magnetic resonance with frequency-modulated \"chirp\" pulses: applications to pairs of scalar-coupled spin I=1/2 nuclei

Geoffrey Bodenhausen

It is shown by simulation and expt. that frequency-modulated "chirp" pulses are very effective for exciting multiple-quantum coherences over large bandwidths. Chirp pulses can be considered as an alternative to composite pulses to combat the effects of l ...

1990

Self-refocusing effect of 270 Deg Gaussian pulses: applications to selective two-dimensional exchange spectroscopy

David Lyndon Emsley, Geoffrey Bodenhausen

A soln. is presented to the problem of phase dispersion in the resultant magnetization for pulses used for high-resoln. NMR work by demonstrating how a Gaussian pulse having an on-resonance flip angle of 270 Deg has much improved phase properties over the ...

1989

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