We present a classical model for bulk-ensemble NMR quantum computation: the quantum state of the NMR sample is described by a probability distribution over the orientations of classical tops, and quantum gates are described by classical transition probabilities. All NMR quantum computing experiments performed so far with three quantum bits can be accounted for in this classical model. After a f...

A portable unilateral nuclear magnetic resonance (NMR) instrument was used to detect in field conditions the water status of leaves of herbaceous crops (Zea mays, Phaseolus vulgaris), mesophyllous trees (Populus nigra), and natural Mediterranean vegetation characterized by water-spending shrubs (Cistus incanus) and water-saving sclerophyllous trees (Quercus ilex). A good relationship was observ...

Recently, it has been reported that certain lots of heparin are associated with an acute, rapid onset of serious side effects indicative of allergic reaction, and (1)H NMR is one of the convenience but strong analytical methods to identify a contaminant in heparin. However, an NMR signal from the contaminant in some cases is overlapped with a satellite peak from heparin, leading a misunderstand...

The surface accessibility of α-bungarotoxin has been investigated by using Gd2L7, a newly designed paramagnetic NMR probe. Signal attenuations induced by Gd2L7 on α-bungarotoxin CαH peaks of H-C HSQC spectra have been analyzed and compared with the ones previously obtained in the presence of GdDTPA-BMA. In spite of the different molecular size and shape, for the two probes a common pathway of a...

The methylated metallocenes (MeCp),M with M = V, Cr, Mn, Co, Ni (1-5) were investigated by 'H and 'H NMR spectroscopy at natural abundance. The 2H NMR signals are narrower by a factor of up to 30 compared with the corresponding 'H NMR signals, thus establishing an inexpensive method and a general improvement of the NMR spectra of paramagnetic x-complexes. This has allowed the resolution of the ...

Spectroscopic imaging (i.e., the combination of nuclear magnetic resonance (NMR) spectroscopy with magnetic resonance imaging) has recently been accepted as a radiological procedure, recognized by health insurance companies. These studies typically use H NMR and quantify various metabolic biomarkers of disease. Recently, pattern recognition algorithms have been applied. The primary problem with...

The return to the origin probability (RTOP) for diffusing molecules is a valuable indicator of porous media microstructure [1-2]. For example, in isolated pores with nonrelaxing walls, the pore volume is related to the RTOP at long diffusion times. Similarly, in disordered media, the temporal scaling of the RTOP is necessary in the estimation of the fractal dimension of the medium [3]. However,...