Electrical conduction, and electronic

MWCNT synthesized by catalytic decomposition of hydrocarbon does not contain nanoparticle nor amorphous carbon and hence this method is suitable for mass production. The shape of MWCNT thus produced, however, is not straight more often than that synthesized by arc-discharge method. This differenee could be aseribed to the strueture without pentagons nor heptagons in graphene sheet of the MWCNT synthesized by the catalytic decomposition of hydrocarbon, which would affect its electric conductivity and electron emission. 

The preparation, supercondictivity, electrical conductivity, and electronic structure of NbSe2 have been reviewed.520 Electron diffraction and X-ray measurements on... 

Out of the multiplicity of catalytic processes, Roginskii has segregated two large groups (1) those processes characterized by electronic transitions and (2) those in which the acidic properties of the catalyst are important. Thus more restrictive conditions on the nature of the process make it possible to associate the catalytic activity with certain physical attributes such as color, electrical conductivity, and electron affinity. Consequently a number of simple rules for the selection of catalysts can be stated. The following characteristics have been noted (1) pronounced effects are noted with highly colored compounds (2) catalysts containing transition elements are exceptionally active and (3) white compounds do not have a pronounced catalytic effect. 

These reactions require ionic intermediates and are catalyzed by acidic or basic solids hke AI2O3 or CaO and especially mixed oxides such as Al203/Si02 and MgO/ Si02. Electronic effects can also successfully explain the phenomena of catalyst promotion and catalyst poisoning. Solid-state catalysts can be classified according to their electrical conductivity and electron-transfer properties as shown in Table 5-14. 

Lerner NR, Electrical conductivity and electron-spin resonance in oxidatively stabilized polyacrylonitrile subject to elevated temperature, J Appl Phys, 52(11), 6757-6762, Nov 1981. Song DY, Park JB, Takeda N, Failure behaviour and electrical property of CFRP and CFGFRP, Key Eng Mater, 183-187, 1129-1134, 2000, Published in Fracture and Strength of Solids, 2000. 

Lemer, N.R., "Electrical Conductivity and Electron Spin Resonance in... 

Lao,6Sro,4Coo.8Feo.20(3-s) cathodes. I. Electrical conductivity and electronic structure. Phys. Chem. Chem. Phys.,... 

In solid materials that are not significantly electrically conductive, molecular vibrations known as phonons are the means of heat conduction. In metals that have free electrons available to conduct electric current, these same electrons provide another means of heat conduction. The electrical conductivity and electronic component of thermal conductivity are related by the Wiedemann-Franz-Lorenz ratio L, as shown in Eq. (1.10) ... 

Fluorimetry is well known for its very high selectivity and sensitivity to very small quantities of some samples occurring in biological fluids while being completely insensitive to many other materials such as durgs, vitamins, and steroids. GC detectors such as electrical conductivity and electron capture are also used in LC. 

Although it is required to refine the above condition I in actuality, this rather simple but impressive prediction seems to have much stimulated the experiments on the electrical-conductivity measurement and the related solid-state properties in spite of technological difficulties in purification of the CNT sample and in direct measurement of its electrical conductivity (see Chap. 10). For instance, for MWCNT, a direct conductivity measurement has proved the existence of metallic sample [7]. The electron spin resonance (ESR) (see Chap. 8) [8] and the C nuclear magnetic resonance (NMR) [9] measurements have also proved that MWCNT can show metallic property based on the Pauli susceptibility and Korringa-like relation, respectively. On the other hand, existence of semiconductive MWCNT sample has also been shown by the ESR measurement [ 10], For SWCNT, a combination of direct electrical conductivity and the ESR measurements has confirmed the metallic property of the sample employed therein [11]. More recently, bandgap values of several SWCNT... 

To interpret the strong dependence of the conductivity from composition, we also evaluated the electronic density-of-states and analyzed its specific atomic contributions. For this discussion and for comparison we also calculated the electrical conductivities and the electronic densitity-of-states using a simplified density-functional (DFT)- based LCAO scheme [12]. 

Applications Although a wide range of metals can be sputtered, the method is often commercially restricted by the low rate of deposition. Applications include the coating of insulating surfaces, e.g. of crystal vibrators, to render them electrically conducting, and the manufacture of some selenium rectifiers. The micro-electronics industry now makes considerable use of sputtering in the production of thin-film resistors and capacitors . ... 

The physicochemical properties of carbonaceous materials can be altered in a predictable manner by different types of treatments. For example, heat treatment of soft carbons, depending on the temperature, leads to an increase in the crystallite parameters, La and Lc and a decrease in the d(0 0 2) spacing. Besides these physical changes in the carbon material, other properties such as the electrical conductivity and chemical reactivity are changed. A review of the electronic properties of graphite and other types of carbonaceous materials is presented by Spain [3],... 

The Research Association of Micro Chemical Process Technology (abbreviation MCPT) was established in July 2002 with the aim to conduct experimental research on micro-chemical process technology through the collaborative work of its members. The association has been implementing R D together with its members from 29 different firms of various industries including the chemical industry, the precision machinery industry, and the electrical equipments and electronics industry. In addition, the participation of national, public, and private universities as well as independent administrative institutions has been greatly appreciated. 

The adsorption of particles of various type results in the change in electric conductivity of such bridges mainly due to local chemical interaction of adsorbed particles with electrically active defects which are electron donors and resulting, thereby, in decrease of their concentration or, on the contrary, in increase due to creation of new defects of this type. In both cases as it has been shown above there are substantially straightforward and easily verified relationships linking both the initial rates in the change of electric conductivity and the stationary values reflecting concentration of adsorbed particles in ambient volume. 

---