42 results about "J-coupling" patented technology

An embodiment of a method of detecting a J-coupling includes providing a polarized analyte adjacent to a vapor cell of an atomic magnetometer; and measuring one or more J-coupling parameters using the atomic magnetometer. According to an embodiment, measuring the one or more J-coupling parameters includes detecting a magnetic field created by the polarized analyte as the magnetic field evolves under a J-coupling interaction.

The invention provides a nuclear magnetic resonance phase-sensitive two-dimensional J decomposition spectrum method for inhibiting a strong coupling pseudo peak. The method is used for multi-peak analysis of a complex chemical sample, and relates to the field of magnetic resonance spectroscopy detection. According to the method, two chirp sweep frequency pulses in opposite directions are adopted to achieve the purpose of restraining strong coupling pseudo peaks, a PSYCHE module is used for acquiring pure chemical shift information at a direct dimension, the evolution effect of J coupling is eliminated, J coupling information is recovered again through the effect of refocusing chemical shift by a J sampling module at an indirect dimension, and data post-processing is performed on a collected original signal to obtain a nuclear magnetic resonance phase-sensitive J decomposition spectrum for inhibiting the strong coupling pseudo peak. The effect of inhibiting the strong coupling pseudo peak is remarkable, and the method has extremely important significance on research of pure chemical shift in a magnetic resonance spectrum.

Provided is a fast two-dimensional J spectrum method applied to a non-uniform magnetic field. By using the characteristic that intermolecular double-quantum coherence signals are immune for non-uniformity of the field, the two-dimensional J spectrum method combining an intermolecular double-quantum indirect dimensional delayed evolution module and a J resolution sampling module is designed, wherein a high-resolution two-dimensional J spectrum can be obtained in the non-uniform filed through fast sampling. According to the intermolecular double-quantum indirect dimensional delayed evolution module, a pair of regression linear selection gradients with the strength radio of 1:(-2) are used for selecting the needed intermolecular double-quantum coherence signals, an complete indirect dimensional evolution period t1 is divided into t1 / 3 and 2t1 / 3, and finally, chemical shift evolution information immune for non-uniform filed interference of the field is obtained. The J resolution sampling module is composed of a sampling period t2 and a nonselective pi pulse, and repeated for 2N times, and J coupling evolution information immune for the non-uniform interference of the field can be fastobtained through once scanning. Finally, through specific data fitting treatment, the high-resolution two-dimensional J spectrum is obtained.

The invention provides a clean and homogeneous layer-selective homonuclear selective coherence spectrum method. The modified perfect echo module is used to realize the coherent transfer between the same phases and combined with selective pulse and dephasing gradient to remove unwanted signals, and finally only the excitation nucleus and the observation nucleus are modulated by the cosine function t 1 , t 2 The temporal J-coupling modulates the signal, and the signal strength is affected by the Δ value. The two-dimensional J-coupling modulation of the excited nucleus and the observed nucleus will present an in-phase square in the spectrum, the coupling information of the observed nucleus and other nuclei is reflected in the lateral offset of the square, and the coupling information of the excited nucleus and other nuclei is reflected in the The vertical offset of the square is on, and since the modulation that causes the horizontal and vertical offset is also a cosine modulation, it will not affect the property that the spectral peaks are in-phase.

The invention provides a nuclear magnetic resonance multidimensional spectrum method for simultaneously measuring the hydrogen-hydrogen coupling constants of multiple coupling networks. Firstly, a 90-degree hard pulse is applied to rotate the magnetization vector from the Z direction to the XY plane. After t1 / 2 time, a selective 180-degree soft pulse is applied, and a magnetic field gradient in the Z direction is applied at the same time, so that the selective 180-degree soft pulse excites different nuclei at different spatial positions. Then apply the PSYCHE module. Gradients of equal strength and direction are applied on both sides of the PSYCHE module to dephase unwanted signals. Then, after t1 / 2 time, the EPSI sampling module is used to obtain chemical shift information and spatial position information at the same time. In this way, the coupling between other nuclei and the nuclei excited by the 180-degree soft pulse in the same layer can be obtained in different layers, and these couplings will show split peaks in the indirect dimension. The corresponding J-coupling constants can then be measured from these split peaks.

A method for high resolution NMR (=nuclear magnetic resonance) measurements using the application of excitation pulses and the acquisition of data points, whereby a dwell time Δt separates the acquisition of two consecutive data points, which is characterized in that one or more tickling rf (=radio frequency) pulses of duration τp are applied within each dwell time Δt, and that the average rf field amplitude of each of the tickling rf pulses approximately fulfills the condition ω1=ω1τp / Δt=πJ wherein J is the scalar J-coupling constant and ω1=γB1 with γ being the gyromagnetic ratio and B1 being the strength of the magnetic component of each tickling rf pulse. This method is effective in decoupling homonuclear couplings.

The invention provides a method for acquiring two-dimensional J-resolved spectroscopy of magnetic resonance by single sweeping. Through a module executing 'sampling and 180-degree pulsing' repeatedly after exciting a magnetization vector to an XY plane, data needed for two-dimensional J- resolved spectroscopy can be acquired by only one-time excitation. In order to acquire better resolution on a direct dimension F2 of a spectrogram, raw data are predicted along the direct dimension F2, and signals are attenuated completely. Compared with a traditional method, the method has the advantage that time of experiment is shortened greatly; compared with a previous spatial encoding method, the method is equivalent to the previous method in experimental time, can provide higher signal to noise ratio and resolution, and is simple in sequence and convenient to operate; compared with a one-dimensional spectroscopy method, the method is equivalent to the method in experimental time, but can provide finer J-coupling split peak information. The simple and efficient method plays an important role in metabolite batch testing, organic chemistry reaction and bioassay.