Magnetic float

Figure 3. Alfred Mayer s experiments with magnets floating in water (illustrated in one of his publications with this sketch) were the template J. J. Thomson used to develop hi9 first electron configurations (see Figure 4. Mayer found that the magnets adopted different patterns depending on the number introduced, leading Thomson to suspect that similar principles would pertain to electron configurations.

Commercial laundry dryers can not be easily vented to the outside in the same way that home laundry dryers are. Because of this fact, the moist air is passed through a condenser where the water will accumulate. If there is no direct water drain, the water is directed to a holding tank. The water level is monitored using a magnetic float. When the water rises to the full level, the reed sensor is activated and shuts down the dryer. Once the water is removed, the reed sensor is deactivated, enabling the dryer to operate. 

The magnetization floats through the iHNCA-TROSY experiment in the following way... 

A. One Atmosphere Densities. The densities or volume properties of solutions have been studied by a number of methods which are extensively reviewed elsewhere (4,5. 6,7) of all of the methods, only the magnetic float (7-14), the hydrostatic balance (3,15-20), the vibrating flow densimeter (21,22), and dilatometric (23,24,25) methods give data with sufficient precision to study the densities of dilute solutions. For more concentrated... 

Figure 2. Sketch of the magnetic float densitometer (A) solution container (B) magnetic float (C) pull down solenoid (D) the main solenoid (E) support and...

By putting the system into a high pressure bomb (36) the magnetic system can be used to measure the densities of aqueous solutions over a wide pressure range with a precision of 11 ppm. We presently are developing a magnetic float system that can be used to measure the densities at low pressures to high temperatures (200°C). 

C. High-Pressure PVT Properties. Three methods are presently being used to measure the high-pressure PVT properties of electrolyte solutions volumetric methods, (26,32,106) high pressure magnetic float systems, (36,107,108) and high pressure speed of sound systems (109,110,111,112). I will not attempt to review all the modifications made to these systems. 

The system is calibrated with water in the same manner as the 1 atm magnetic float system. The density of platinum as a function of pressure was estimated from the compressibility. 

FIGURE 10.4 A permanent magnet floating over a superconducting surface. (Courtesy of Darren Peets, UBC Superconductivity Group.)... 

So, you drop that little disc of ceramic into the liquid nitrogen—you can put it all in a styrofoam cup—and put a little magnet on top. If the magnet floats, you ve got a superconductor, the Meissner effect. 

Meissner test A small magnet is placed over a ceramic disk in liquid nitrogen if the magnet floats, that is evidence of superconductivity. 

At an early stage of the project we tried using a reed switch/magnetic float device that looked very promising on paper, but when we tried the technique out, the laws of physics got in the way. We quickly found out how tenaciously magnets can cling to reed switches. 

In an attempt to resolve these discrepancies Benson has used two further methods involving the direct determination of the density of mixtures of benzene + cyclohexane. One method uses a magnetic float densimeter capable of a precision of 20 x 10 in the density which corresponds to a precision of about 0.002 cm mol in the excess volume. The results agreed within experimental error with those of Stokes et al. The second method, using an Anton Paar mechanical oscillator densimeter, is capable of about the same precision as the first method and the results agreed to within 0.002 cm mol- . 

Figure 7 illustrates the treatment of the data for 3-methylpentane + nitro-ethane by Wims et a/., showing A, the coexistence curve B, a Cox-Herington plot, and C, a log p" - p vs. log r 1 plot. (Densities p rather than mole fractions x are shown, because there were the quantities directly measured by a magnetic-float technique.)... 

Mayer s floating magnets. From Alfred M. Mayer, On the Morphological Laws of the Configurations Formed by Magnets Floating Vertically and Subjected to the Attraction of a Superposed Magnet With Notes on Some of the Phenomena in Molecular Structure Which These Experiments May Serve to Explain, American Journal of Science,... 

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