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This paper reviews our portable multi-dimensional nuclear magnetic resonance (NMR) spectroscopy system combining a 4-mm2 CMOS NMR spectrometer integrated circuit (IC) and a permanent magnet. The work was first reported in [1] with emphases on overall system development and spectroscopy experimentations. Here we pay more attention to the IC design. The scalability of the integrated spectrometer can...
We present high-performance MR imaging and spectroscopy results obtained with wire bonded solenoidal microcoils manufactured in a MEMS-integrated technology. We report MR testing of 400 μm inner diameter solenoidal microcoils for imaging of Eremosphaera Viridis algal cells with 10 μm isotropic resolution. NMR spectroscopy has been performed on a water sample obtaining a linewidth of 0.04 ppm. The...
Both THz-TDS and NMR techniques were employed to study the hydrogen bonding networks formed in 2-propanol/water mixtures. The composition of such solvent mixtures is shown to significantly impact on the mobility of the solute molecules.
A high power THz radiation source is needed to analyze the structures of complex proteins by DNP-NMR spectroscopy. For this objective, we have been developing gyrotrons having boardband frequency tunability using a long cavity. Prototype gyrotron was achieved with a tuning range of 1.6 GHz and exceeded output power of 10 W.
“Cold-hot nature” is the key part of the theory on herb properties in traditional Chinese medicine (TCM). Traditionally, the cold-hot natures of medicinal herbs were ascertained mainly dependent on medicinal experience. Nowadays systematic methods considering the material basis from a variety of chemical substances are needed and may be reliable to differentiate cold-hot nature of various herbs. In...
1H NMR spectroscopy was utilized to distinguish the brands of rapeseed oils. As there are more than four hundreds of NMR variables, uninformative variables should be eliminated to improve model's discrimination ability and save the calculation time. A hybrid variable selection which is combined with uninformation variable elimination (UVE) and successive projections algorithm (SPA), was used to achieve...
The gyrotron, Gyrotron FU CW IV continues to produce output radiation in the wide range of magnetic fields from 4.9 T to 5.2 T, and continuous frequency tuning in 6 GHz interval from 134 GHz to 140 GHz can be realized. This type of gyrotron will play an important role as a high power radiation source with the function of continuous frequency tuning to the applications in the fields of millimeter to...
We have developed the Gyrotron FU CW VII for 300 MHz and 600 MHz DNP-NMR spectroscopy. For high frequency DNP-NMR experiment, high power sub-THz radiation sources are required. Gyrotron is able to emit enough power and appropriate frequency in sub-THz region for DNP. This Gyrotron emits electromagnetic waves with high power and appropriate frequency for each DNP-NMR spectroscopy (used cavity modes...
NMR spectroscopy is a powerful technique used in protein research for comprehensive functional characterizations, e.g. structure determination at atomic resolution. Due to the molecular size (typicallyGt1000 atoms), protein NMR spectra contain a large number of signal frequencies. Resolving these requires high-dimensional spectroscopy. However, when the number of frequency exceeds three, conventional...
This study aims at developing in vivo exploration based on NMR (Imaging and Spectroscopy) using implantable micro coils ldquoNeedle coilsrdquo. Analysis of highly localized tissue of few nanolitres with this ldquominimardquo invasive method is possible. Reinforced by acquisition and signal processing methodology, it aims at pushing the limits of in vivo detection, thus opening the way to a number...
A sensitive NMR spectroscopy using a dynamic nuclear polarization (DNP) is an effective method to enhance the sensitivity of such versatile analytical technique. Its high performance realization requires a frequency tunable and powerful radiation source. A new gyrotron is developed with the aim of achieving the wide frequency tuning. The gyrotron FU CW IV operates at magnetic fields in the range of...
Summary form only given. Recently, gyrotron-based spectrometers suitable for nuclear magnetic resonance (NMR) studies have been constructed to study dynamic nuclear polarization which can result in significant enhancement of the NMR signal. In the present paper multimode calculations of a low-power (above 10W) high-frequency (200 GHz -300 GHz) gyrotron for NMR spectroscopy applications have been performed...
Alterations in the levels of phospholipid metabolites and variations of intracellular pH may represent early biochemical responses of cells to altered conditions of proliferation in vitro and in vivo. These metabolic alterations can be studied by /sup 31/P NMR (nuclear magnetic resonance) in intact tissues, by respectively analyzing the resonances contributing the phosphorylmonoester and phosphoryldiester...
To improve the accuracy of the quantitation for in vivo nuclear magnetic resonance (NMR) spectroscopy, test protocols and procedures are developed. Preliminary test objects included (1) a set of spheres or boxes of varying sizes, either empty or filled with compounds with certain chemical shift values; (2) an object consisting of a set of parallel flat compartments, with each compartment filled with...
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