Magnetic principle

More space will not be devoted to applications of the magnetic principle of agitation. The advances already made have greatly simplified many mixing, stirring, and agitation procedures, and it is likely that many further applications will be made. 

D. Craik, Magnetism Principles and Applications , Wiley, New York 1995. 

Magnetic principles are used, as well as inductive, capacitive, and optical sensors. In many applications, where cost requirements predominate over performance and reliability issues, simple potentiometers are often found. The market volume in 2002 is about 150 million units and will approach 300 million units, worth more than 1700 million, in 2008. 

Magnetic-field sensors are widely used in automotive applications because of their robust design, their non-contacting and thus wear-free operation and their low manufacturing costs, in particular for solid-state sensors, which can be fabricated using batch processes. Their main fields of application in automobiles are speed and position sensing. In total, about one third of today s automotive sensors are based on the magnetic principle [1],... 

This chapter describes the operating principle, fabrication, and application of a variety of sensors made of magnetic materials and based on the principle of electromagnetic induction. To well describe these systems, fundamental magnetic principles, such as magnetic induction theory and material properties, are also briefly described along with representative examples of these sensors and their applications, with a focus on the area of biomedical engineering. 

Faraday s induction law, as a fundamental magnetic principle, states that a voltage across a closed electrically conducting loop is proportional to the time rate of change of the magnetic flux that passes through... 

Dry film thicknesses on steel surfaces are determined by magnetic and eddy current nondestructive test instruments. The most popular instruments employ the magnetic principle measuring magnetic attraction, which is inversely proportional to the lining thickness. Examples are the BSA-Tinsley thickness gauge and the Elcometer 157 pulloff gauge. 

Electrical engineering is associated with the application of electrical and magnetic principles to the design, analysis, and performance of devices and services. This covers a very broad set of subtopics. In most technical universities, the largest engineering department is that concerned with electrical-related subjects. 

Schematic view showing the principle of nuclear magnetic resonance.

The principle physical phenomenon of applying the eddy current method for evaluating the amount of residual austenite in the structure of quenched steel is magnetic induction, involving the influence of the changeable magnetic field on the studied area, found under the probe. 

The eddy current method allows to evalute the state of stress in ferromagnetic material. The given method is used for determining own stress as well as that formed in effect of outside load. With regard to physical principles of own stress analysis, the dependence between the magnetic permeability and the distance between atomic surfaces is utilized. 

The offered method has allowed essentially to simplify the X-ray apparatus main circuit, to reduce weight and dimensions of the apparatus, to increase sensitivity and reliability of the inspection and to ensure the apparatus control by a computer The main principle is based on the operation of the transformer controlled by magnetic commutation (TCMC). 

Prokhorenko P.P., Baev A.R., Grintsevich E.M. Physical Principles and Application of Magnetic Fluids to Ultrasonic Testing -. Journal of Magnetism and Magnetic Materials. -... 

Principle of Magnetic Flux Leakage for detection of wall loss... 

An important application of the HMT is the test for ferrous inclusions in high pressure turbine disks made from a non-magnetic metal alloy. On principle, such ferrous inclusions can be introduced during the manufacturing process and, if present, they can be the origin of cracks in these most critical parts. Therefore such tests are stringent necessary. 

Conventional covermeters operating on the principle of electro-magnetic fields are capable of determining depth of cover to reinforcement down to about 100 mm with an accuracy of 5 % provided the bar diameter is known and the spacing between individual bars is greater than about 150 mm. If bars are spliced then the covermeter will underestimate the cover depth. 

Ernst R R, Bodenhausen G and Wokaun A 1987 Principles of Nuclear Magnetic Resonance in One and Two Dimensions (Oxford Clarendon)... 

Siichter C P 1990 Principles of Magnetic Resonance (Beriin Springer)... 

In electron-spin-echo-detected EPR spectroscopy, spectral infomiation may, in principle, be obtained from a Fourier transfomiation of the second half of the echo shape, since it represents the FID of the refocused magnetizations, however, now recorded with much reduced deadtime problems. For the inhomogeneously broadened EPR lines considered here, however, the FID and therefore also the spin echo, show little structure. For this reason, the amplitude of tire echo is used as the main source of infomiation in ESE experiments. Recording the intensity of the two-pulse or tliree-pulse echo amplitude as a function of the external magnetic field defines electron-spm-echo- (ESE-)... 

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