SU1626196A1 - Measure of active losses - Google Patents

Abstract

The invention relates to a measurement technique and can be used in instrument making. The purpose of the invention is to increase accuracy and expand the range of measurements. The essence of the invention is to use the precession of the nuclei of a substance during their magnetic resonance, and a substance (copper chloride) with a large local internal magnetic field on the cores is chosen as sample 3, which plays the role of the main part of the magnetizing field. a source of an additional magnetic field that removes substance into resonance, a permanent (for example, cobalt-simarium) magnet 5 is used, located at the bottom of a removable cup 4, which is put on and removed from the measuring cell, rzhaschey shorted coax 1, turned and removes nuclear magnetic resonance veschestge. This corresponds to the insertion and removal of losses from the measuring cell. The invention allows a measure of purely active loss of high accuracy in the region of small values. on the RF and microwave bands. 1 il. (/)

Description

3

The invention relates to magnetic measurements in the high frequency (microwave) range and can be used in metrology, instrument making, in the development and production of new magnetic materials with low losses.

The aim of the invention is to improve the accuracy and the expansion of the measurement range.

The drawing shows a measure of active losses.

The measure of losses consists of a measuring cell, which is a segment of a short-circuited coaxial 1 with a connector 2 for connection to the measurement object and with sample 3 placed in the short circuit plane, removable cup 4, which ensures (when put on) the fixation of the position of the magnet 5 relative to sample 3. This is achieved by using a gasket 6, an internal groove 7 on the cup 4, and a guide protrusion 3 up of the coaxial 1. The cup 4 is fixed to the coaxial 1 by a flare nut 9, a ring protrusion 10 threaded on the coaxial 1 and b rtikom 11 in the open part of the cup.

The measure of losses works as follows.

Magnet 5 is glued to the bottom of the glass. Glass 4, gasket 6, cap nut 9, the cell are made of non-magnetic material (brass). Sample 3 is a thin-walled plexiglas-shaped cassette in the shape of a torus with a lid fixed on a thread filled with a substance (copper chloride). Pattern 3 is glued to coax 1

Zero calibration of calibrated media; Measurement is performed by connecting a cell with sample 3 through connector 2 (cup 4 is removed), then losses are made by NMR by applying a constant (in this case supplementing the local field) magnetic field (the cup with magnet is attached). Sample 3 is made of a CuCl2-2Hgo medium with a large internal local magnetic field on the chloride cores, and the newly introduced magnetizing device is a permanent (for example, cobalt-samarium) magnet 5, for example, a disk-shaped form with poles on planes the disk, which is fixed on the bottom of the removable glass 4, having an internal longitudinal groove 7 and a gasket 6 of non-magnetic material

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between the bottom of the coaxial 1 and the magnet, which, together with the guide protrusion on the coaxial 1, fixes the position of the magnet relative to the sample, the collar P on the open part of the glass 4, the cap nut 9 and the thread under it serve to fix and separate the glass with the magnet.

To cause nuclear magnetic resonance (NMR) in the sample, i.e. In order to make a loss, it is necessary to apply a constant magnetic field B and a high-frequency field of the measuring cell.

As sample 3, copper chloride O was chosen, which has a large internal local magnetic field on the cores (76000 Gs at 200 HHz), which serves as the main part of the external magnetic field B. To excite NMR, it is sufficient to add an external field at 204 MHz about SO Gs. Such a solution makes it possible to eliminate the very energy-intensive and metal-consuming construction of a dp for obtaining a powerful external floor of about 76,000 H. Also, copper chloride has local flooring at room temperature, i.e. in the paramagnetic phase and thereby eliminates the cooling of the sample to the helium temperatures necessary to bring the substance into an antiferromagnetic state.

In order to exclude the power source of an additional magnetic field of about 100 Gs, a cobalt-Samarium disc-shaped magnet with poles on planes attached to a removable cup 4 was used as a magnetizing device. The position of the magnet 5 is fixed relative to the sample 3 by a longitudinal groove on cup 4 and a non-magnetic gasket 6. A glass 4 with a magnet 5 is attached to the measuring cell with a cap nut 9. In this case, an additional field is applied to the sample and provides NMR in the substance. When removing the cup 4, the resonance conditions are violated, the spin precession is absent.

The proposed active loss measure makes it possible to increase the accuracy by eliminating transient resistance variations, to reproduce small values of the tangent of magnetic losses 10 by 200 MHz (for carbonyl iron 10-2 -), to exclude a powerful power source for NMR excitation.

Claims (1)

Invention Formula An active loss measure containing a measuring cell made of a short-circuited coaxial segment with a connector for connection to a test object of measurement, and a reference sample that fills the internal volume of the coaxial in the short-circuit zone of the coaxial, which is accuracy and expansion dia five Measurement area, magnetizing unit inserted in a permanent magnet saw placed on the bottom of a removable cup with an internal longitudinal groove for fixing a guide protrusion made on the outer side surface of the coaxial, and a shoulder on the open part of the cup to fix the cup on the threaded ring the protrusion made in the area of the coaxial connector by means of a cap nut, the permanent magnet being separated from the surface of the bottom of the coax by a gasket of a non-magnetic material, and the sample is made of copper chloride .