Faraday balance

Selected entries from Methods in Enzymology [vol, page(s)] Theoretical aspects, 76, 354-356 diagmagnetic contribution, 76, 358-359 experimental methods, 76, 356-360 Faraday balance technique, 76, 360-361 Gouy technique, 76, 357, 360 instrumentation, 76, 360-369 oxygen contribution, 76, 360, 368 sources of experimental errors, 76, 359-360 SQUID magnetometer use, 76, 364-365 thermal equilibria, 76, 358, 370 thermal expansion, 76, 358. 

Fig. II. A single-crystal Faraday balance (12) for measurements in the temperature range 20-300°K (a) general view, (b) the cryostat, (c) the crystal suspension.

The paramagnetism of 0 can also be measured by means of a Faraday balance (2fL). This technique has the advantage of being applicable to in situ measurments at high temperatures and is sensitive enough to detect 0" in synthetic MgO (2 ). We are currently pursuing this work with a Faraday balance and hope shortly to be able to report on new data. 

Figure 2. Variation of the saturation magnetization of 1 mg iron metal with tern-perature as recorded by a Faraday balance. Note that the apparent weight (saturation magnetization) of iron is much greater than its actual weight.

Magnetic susceptibility measurements were carried out using a Faraday Balance from 77 to 300 K with a field strength of 10.4 kOe. Honda-Owen (field dependency) measurements were carried out at both 77 and 296 K. 

However, when the measurements are done at higher fields (e.g. using a Faraday balance with the typical value of B = 1.5 T) the microcrystals may tend to orient themselves and the measured susceptibility is no longer a correct average. It is apparently higher than Xav-... 

Even with the effort it took for us to set-up our Faraday balance for the measurement of a high-spin carbene molecule, the set-up was not convenient and we needed a lot of experience and special techniques to handle and control the apparatus. Therefore, we always felt the necessity of a convenient new procedure equipped with irradiation system in place of a Faraday balance for investigating magnetic properties of carbenes. From the late eighties, SQUID magneto/susceptometer became commercially available at a reasonable price (still expensive) and relatively easy to obtain. It was easy to operate even for us. 

Attempts to measure losses on the model conductors were unsuccessful because of the presence of a very large, temperature-dependent paramagnetic moment. Subsequent measurements on a Faraday balance revealed a large paramagnetic susceptibility (1.9 x 10 " emu/g at 10 K), which was evidently due to the Cu-30% Ni alloy used in the mixed matrix conductor. Work is in progress to determine if this is intrinsic to the alloy or due to impurities and to determine if there is a loss associated with this susceptibility. 

The authors wish to acknowledge the capable technical assistance of L. Alley and J. P. Rudd in performing the stability and loss measurements. F. J. Di Salvo of Bell Telephone Laboratories performed the Faraday balance susceptibility measurements. 

Som] Squid magnetometry and Faraday balance Magnetization and magnetoresistance... 

Several methods can be used to measure Xm= -g. the Gouy balance (Figure 21.25), the Faraday balance (which operates in a similar manner to the Gouy balance) and a more... 

Morris, B.L. and A. Wold Rev. Sci. Instr. 39 Faraday balance for measurement of magnetic... 

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