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A pulsed field gradient NMR (= nuclear magnetic resonance) method using stimulated echoes for determining the translational isotropic or anisotropic diffusion coefficient of a molecule or supramolecular assembly or the flow rate and direction of fluids con ...
We show how high-resolution NMR spectra can be obtained for solids for which the spectra are normally broadened due to structural disorder. The method relies on correlations in the chemical shifts between pairs of coupled spins. It is found experimentally ...
We present the results of high magnetic field (up to 30 T) and temperature (50 mK-80 K) dependent transport measurements on a 2DEG in GaN/AlGaN heterojunctions. A high mobility (above 60000 cm(2) V-1 s(-1) at 4 K) 2DEG was obtained by MBE growth of disloca ...
Using constrained ab initio molecular dynamics, we investigate the reaction of the O-2 molecule at the Si(100)-SiO2 interface during Si oxidation. The reaction proceeds sequentially through the incorporation of the O-2 molecule in a Si-Si bond and the diss ...
LaCoO3 perovskite was prepared at 700degreesC using citrate precursors. The product was then characterized with X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). The powder XRD pattern indicates rhomboliedral (R (3) over barc) or its monocli ...
The study of electron spin relaxation in aqueous Gd(III) complexes is the source of new insights into the physics and chemistry of magnetic resonance imaging (MRI) contrast agents. The coupling of the seven unpaired electrons of the Gd(III) ion with the su ...
We present studies on the low-temperature magnetization of a two-dimensional electron system (2DES) in the integer quantum Hall-effect regime. The 2DES was formed in a modulation-doped AlGaAs/GaAs heterojunction. Using molecular-beam epitaxy it has been in ...
A new expt. allows the identification of residues that feature slow conformational exchange in macromols. Rotations about dihedral angles that are slower than the global correlation time tc cause a modulation of the isotropic chem. shifts of the nuclei. If ...
In magic angle spinning solid-state NMR, the homonuclear J-couplings between pairs of spin-1/2 nuclei may be determined by studying the modulation of the spin echo induced by a pi-pulse, as a function of the echo duration. We present the theory of J-induce ...
We performed an Eu153 and Eu151 NMR study of EuO and Gd doped EuO using a home-made spectrometer designed to measure signals with fast spin-spin relaxation times. We determined and described the broadening mechanisms giving rise to the structure in the lin ...