Material characteristic properties Conductivity

Two parallel plates of conducting material separated by an insulation material, called the dielectric, constitutes an electrical condenser. The two plates may be electrically charged by connecting them to a source of direct current potential. The amount of electrical energy that can be stored in this manner is called the capacitance of the condenser, and is a function of the voltage, area of the plates, thickness of the dielectric, and the characteristic property of the dielectric material called dielectric constant. 

In Chapter 3, four examples of non-stoichiometric compounds used as practical materials are described from a chemical point of view. The sections on ionic conducting materials and hydrogen-absorbing alloys concentrate on how to utilize the characteristic properties of these compounds, in relation to their non-stoichiometry. In the section on magnetic and electrical materials, methods of sample preparation, focusing on the control of non-stoichiometry, and the relation between non-stoichiometry and the properties of the compounds are presented. 

Figure 44. Scheme showing the possible routes for the development of molecular devices by exploiting the characteristic properties of molecular materials (e.g., conductivity, photochemistry, catalysis) (shown inside the circle) for the generation of functional devices (outside circles). 

LSE, the classical electrochemistry, is concerned with electrochemical cells (ECs) based on liquid ionic-conductors (liquid electrolytes (LEs)). Solid-state electrochemistry is concerned with ECs in which the ionic conductor (electrolyte) is a solid. Both fields are based on common thermodynamic principles. Yet, the finer characteristics of ECs in the two fields are different because of differences in the materials properties, conduction mechanisms, morphology and cell geometry. Differences that come immediately to mind are (1) The lack of electronic (electron/hole) conduction in most LEs, while electronic conduction exists to some extent in all solid electrolytes (SEs). (2) In LEs both cations and anions are mobile, while in SEs only one kind of ions is usually mobile while the other forms a rigid sublattice serving as a frame for the motion of the mobile ion. An... 

A large number of correlations are listed in the literature for the estimation of thermal conductivity as a function of characteristic properties of the material. Such relations, however, have limited practical utility since the values of the necessary properties are not readily available. 

Diamond s combination of properties make it a unique material. Although hardness is its primary characteristic, thermal conductivity, compressive strength, refractive index, spectral transmittance, and chemical stability are either the highest or among the highest found in nature. 

Silicon is a nonmetallic chemical element that is used quite extensively in the manufacturing of transistors and various electronic and computer chips. Pure silicon is not found in nature it is found in the form of silicon dioxide in sands and rocks or found combined with other elements such as aluminum or calcium or sodium or magnesium in the form that is commonly referred to as silicates. Silicon, because of its atomic structure, is an excellent semiconductor, a material whose electrical conductivity properties can be chai d to act either as a conductor of electricity or as an insulator (preventor of electricity flow). Silicon is also used as an alloying element with other elements such as iron and copper to give steel and brass cert desired characteristics. 

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