Magnetic susceptibility apparatus

Carburization performed in magnetic susceptibility apparatus except for two runs in the tubular reactor (T). 

The effect of heating rate during carburization (H2/CO = 3/1) on the magnetic properties of the catalysts were studied at 1 atm in the magnetic susceptibility apparatus and in the tubular reactor (Table VII). The mass gain of the samples carburized at 1 atm in the susceptibility... 

FIGURE 10.1 Modified Gouy Magnetic Susceptibility Apparatus within an Analytical Balance Chamber. (Modeled after the design in S. S. Eaton, G. R. Eaton, J. Chem. Educ.,... 

Electrobalances suitable for thermogravimetry are readily adapted for measurements of magnetic susceptibility [333—336] by the Faraday method, with or without variable temperature [337] and data processing facilities [338]. This approach has been particularly valuable in determinations of the changes in oxidation states which occur during the decompositions of iron, cobalt and chromium oxides and hydroxides [339] and during the formation of ferrites [340]. The method requires higher concentrations of ions than those needed in Mossbauer spectroscopy, but the apparatus, techniques and interpretation of observations are often simpler. 

Fig. 11.54 Schematic diagram of apparatus used for the Faraday determination of magnetic susceptibility. The sample is suspended bdween magnet poles that have been carefully shaped so that the value of HJlSHISx) is constant over the region occupied by the sample.

The magnetic susceptibilities of CoO(II), CoO(I), CoO(I,II) have been measured2 over the temperature region 300° - 700°K.The DTA measurements on CoO (II) in the temperature region 300° - 850°K in vacuum and Ar. Atmosphere were done in sealed Pyrex glass ampule by using the conventional DTA apparatus. 

A simple apparatus used to measure magnetic susceptibilities (a Gouy balance) is shown in Figure 25-1 ... 

Characterization of Superconducting Properties. The real part of the complex AC magnetic susceptibility has been used as a tool for the detection of the superconducting transition temperature. The apparatus used was similar to that described in reference (6), with modifications made for use of an electronic thermometer with analog output and a nitrogen gas flow system for cooling... 

The magnetic susceptibility of these microcrystals as well as commercial platinum foil (99.9%) [Johnson Matthey] has been measured at 300 K using a Faraday apparatus described elsewhere, and their susceptibilities are equal within experimental error (1.00 0.07 and 0.989 0.004 cm /g, respectively). However, low-temperature susceptibility measurements on these microcrystals have revealed a Curie-Weiss law behavior below about 150 K, which has been attributed to their very small size. ... 

The measurements were conducted by the Gouy method under a vacuum of 10" torr over the temperature range 170-560 K, using the apparatus described previously [6]. Typical temperature relationships obtained are shown in Fig. 1, which shows that the magnetic susceptibility of the solid solutions, which are diamagnetic, usually varies only slightly with temperature. 

For experimental details, high pressure apparatus and techniques, references to original articles can be found in the review by Bloch and Pavlovic (1969). Briefly, the most common methods used in following a magnetic transition are change in the mutual inductance sensed through a set of coils placed around the specimen in a transformer-like set up, magnetic susceptibility, electrical resistivity and in some cases thermal dilation. To a limited extent more sophisticated... 

For the following measurements, grind the sample and make the measurement quickly so as to minimize oxidation of the sample. Record the IR spectrum of chromium(n) acetate monohydrate either as a KBr pellet or as a Nujol mull between KBr plates. If apparatus is available, record the magnetic susceptibility. 

This high-pressure apparatus has been used for several different kinds of measurements such as electrical resistance, magnetic properties (magnetic susceptibility and magnetization), and thermal expansion (Honda et al., 2002). The thermal expansion at high pressure and high magnetic... 

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