Piezoelectric substance

Fig. 4.6. Piezoelectric pulse diagrams can be used to obtain explicit representations of the time dependent electric fields in piezoelectric substances. The magnitudes and orientations of these electric fields are critical to development of shock-induced conduction. As an example, the diagram on the left shows the polarization and displacement relations for a location at the input electrode. The same functions for a location within the crystal is shown on the right (after Davison and Graham [79D01]).

When this polymer is processed in a particular way, it becomes piezoelectric and pyroelectric. A piezoelectric substance produces an electric current when it is physically deformed or alternatively undergoes a deformation caused by the application of a current. A pyroelectric material is one that develops an electrical potential in response to a change in its temperature. 

Surface acoustic wave (SAW) technology utilizes the production, control, transmission, and reception of acoustic waves formed on the surface of a piezoelectric substance. It has been used in telecommunications applications for over 50 years. SAW devices are used in mobile cellular phones and base stations as band-pass filters, and also serve as sensors for many other applications such as torque, pressure, temperature, humidity, and chemical sensors. 

In the ceramics field many of the new advanced ceramic oxides have a specially prepared mixture of cations which determines the crystal structure, through the relative sizes of the cations and oxygen ions, and the physical properties through the choice of cations and tlreh oxidation states. These include, for example, solid electrolytes and electrodes for sensors and fuel cells, fenites and garnets for magnetic systems, zirconates and titanates for piezoelectric materials, as well as ceramic superconductors and a number of other substances... 

An important class of materials that originates from the precursor core-shell particles is hollow capsules. Hollow capsules (or shells ) can be routinely produced upon removal of the core material using chemical and physical methods. Much of the research conducted in the production of uniform-size hollow capsules arises from their scientific and technological interest. Hollow capsules are widely utilized for the encapsulation and controlled release of various substances (e.g., drugs, cosmetics, dyes, and inks), in catalysis and acoustic insulation, in the development of piezoelectric transducers and low-dielectric-constant materials, and for the manufacture of advanced materials [14],... 

Dielectrics, Ferroelectricity, and Piezoelectricity. A dielectric is a material separating two charged bodies, as illustrated in Figure 6.22b. For a substance... 

Theoretical considerations and interpretations on the origin of piezoelectricity which will be described in this review may apply to these biological substances and polymeric materials of bulk form. The experimental results to be discussed in this review, however, will be limited to those on films of synthetic polymers, for which most extensive work has been carried out by various authors in recent years. 

CURIE, PIERRE (1859-1906) CURIE, MARIE (1867-1934). Pierre Cume was bom and raised in Paris. With his brother. Jacques, he studied crystals and in 1880 discovered piezoelectricity. Piezoelectricity is the production of an electric charge by pressure on certain crystals. Pierre became director at the School of Industrial Physics and Chemistry in Paris where he worked for 22 years. His doctoral thesis on magnetism led lo his discovery, the Curie point, a temperature at which ferromagnetic substances lose their magnetism. 

Other devices include the Vieille Bomb, Manometric Crusher Bomb of the "Commission des Substances Explosives , Petavel Manometric Bomb, Manometric Piezoelectric Bomb, Krupp Bomb, etc Refs l)Marshall 2(1917),444-5 2)Marshall 3 (1932),133 3)Vennin,Burlot Lecorche(1932),... 

H. Joachim H.Ilgen, SS 27, 76-9 121-25 (1932) (Gas pressure measurements using piezoelectric indicator) 10)Marshall 3 (1932) I33 (Closed bomb and pressure measuring devices) ll)Vennin, Burlot Lecorche (1932), 72-87 (Closed vessel and various pressure measuring devices used between WWI WWII in the laboratories of the Commission des Substances Explosives) 12)C. 

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