Apparent weight loss

Electric treatment may result in the redeposition of a metal, such as copper, from reducible corrosion products, and thus decrease the apparent weight loss. 

All rabbits selected for the study must be in good health any rabbit exhibiting sniffles, hair loss, loose stools, or apparent weight loss is rejected and replaced. 

There is still another method by which the density of insoluble solids can be determined. It is based on an ancient principle known as Archimedes principle when an object is suspended in a fluid, it APPEARS to lose weight equal to the weight of the fluid displaced. We say that the object is "buoyed up," and that the "buoyancy" is equal to the apparent weight loss. In equation form, Archimedes principle could be stated as... 

Weight of metal object in air = 25.0 g Weight of metal object in water = 15.0 g Buoyancy = apparent weight loss = 10.0 g By Archimedes principle,... 

Fig. 2 shows how a CDA experiment may typically be performed. The obsidian was heated in steps (at 80°C/min) and allowed to thermally equilibrate for 4-6 min. A bias of -75 V was then applied. The force F, expressed as apparent weight loss Am, was measured at a function of time (solid lines). The bias was removed and the return to the baseline was monitored (dashed lines) before T was raised to the next value. In an ideal dielectric (Po only) the response Am will... 

As shown in Fig. 12, the weight loss of PFPE for Sample 1 was very small during the whole 250 minutes reaction process, except for an apparent loss in the first 20 minutes because of evaporation. For Sample 3, the weight loss was similar to that of Sample 1, so that the reaction between PFPE and X-IP was very weak. However, for Sample 2, PFPE + AI2O3, the reaction rate was expected to increase greatly with time because the weight loss grew very fast with... 

A chemical investigation of the surface oxides on diamond was undertaken by Boehm et al. (35). Using a fine particle size diamond powder with a specifie surface area of 17 m /gm, the oxidation was studied by use of a vacuum microbalance. Formation of surface oxides started at a measurable rate with pure oxygen at 260°. A weight loss due to formation of carbon oxides became apparent above 360°. 

Determinations of active hydrogen with methyllithium and with methylmagnesium iodide were undertaken by Uytterhoeven and Fripiat (366). Only after outgassing at 600° or higher, did the results of both methods agree with each other and with the weight loss on calcination. The reactions proceeded more slowly than with Aerosil silica (195). Apparently, diffusion into the pores is hindered, especially with the Grignard compound. 

Petersen 87, 120) discusses the use of profile data to understand better the mechanism of the carbon-carbon dioxide reaction. He reacted diameter rod samples in an apparatus previously described 85). Profile data were determined on the reacted rods as follows A 3 -in. hole was drilled through the center of the rod prior to placing it on an ordinary screwcutting engine lathe. Following incremental cuts of approximately 0.25 mm. from the exterior surface, the rod was removed from the lathe and weighed, and its diameter was determined by a micrometer caliper. For each cut, the apparent density of the material removed was calculated from the weight loss and volume of carbon removed. 

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