nmr probe with multi-piece lower insert

Abstract

A temperature-adjustable NMR probe having a disk-shaped lower insert and supporting and holding the electrical and mechanical components of the NMR probe, wherein the lower insert is multi-part and includes two surface-like contacts in the assembled state Disk-shaped sub-elements perpendicular to the z-axis that are not mechanically firmly interconnected, the first sub-element satisfies the electrical insulation of the high-frequency and high-voltage conductors guided through the lower insert in terms of material selection and geometry function, the first subelement has a sigma <10 3 S / m and fulfills the mechanical holding function of the component of the NMR probe formed on the lower insert, the second sub-element assumes the mechanical holding function of the first sub-element on the main frame of the NMR probe in terms of material selection and is composed of Made of malleable plastic or metal with high mechanical breaking strength σ>100N / mm respectively 2 and high melting temperature Ts>250℃. High breaking strength against thermal stress is achieved while ensuring the required high frequency and high pressure characteristics.

Description

technical field [0001] The invention relates to a temperature-adjustable NMR (=nuclear magnetic resonance) probe with an HF (=high frequency) coil system arranged around a vertical z-axis and a disk-shaped lower insert arranged perpendicular to the z-axis, NMR The electrical and mechanical components of the probe, in particular the HF coil system as well as the HF and HV (=high voltage) conductors, are supported and held by means of the lower insert. Background technique [0002] Such a device is known from DE 10 2012 217 601 B4 (=ref. 1). [0003] NMR spectroscopy is a powerful instrumental analysis method. Here, radio-frequency pulses are irradiated into the measurement sample in a strong static magnetic field, and the radio-frequency response of the measurement sample is measured. The information is then obtained in its entirety over a certain area of ​​the measurement sample, the so-called active volume. The measurement sample usually consists of a cylindrical sample ...

AI Technical Summary

Problems solved by technology

[0007] In the temperature-adjustable probes known from the prior art, the hitherto always one-piece lower insert is made, for example, of quartz or made of material, but said material does not have a particularly high breaking strength

Therefore, under mechanical stress of the lower insert, for example when coupling a dewar vessel for a cooling device, it is easy to cause component fractures, which usually require very high repair and replacement costs

Even thermal stress can cause such trouble if conventional lower inserts do not withstand these loads durably

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