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Electrical conductivity construction

Static electricity Inert milling system generation both, Control/interlock with oxygen concentration in mill and con- monitoring veying equipment bond all electrically conductive components Use conductive materials of construction CCPS G-12 CCPS G-23 CCPS G-29 CCPS G-32 ISAS84.01 NFPA 654... [Pg.98]

Type tests are conducted on the first enclosure of each voltage, current rating and fault level to demonstrate compliance with electrical and constructional design parameters. The tests provide a standard reference for any subsequent enclosure with similar ratings and constructional details. The following tests may be conducted to demonstrate verification of the following ... [Pg.421]

Current control can be more advantageous where rail/soil potentials are predominantly positive. Current control is also preferred in the cathodic protection of steel-water construction if the anode resistance fluctuates due to changes in electrical conductivity. [Pg.234]

Instead of electrically conductive additives, thermally conductive additives have also been used to construct thermally conductive tapes used for heat management [ 132]. A particular example of an electrical conductive tape is a z-axis conductive construction shown in Fig. 17. In this case, the conductive particles make contact in the z-direction of the tape without doing so with neighboring particles in the... [Pg.519]

Beryllium is obtained by electrolytic reduction of molten beryllium chloride. The element s low density makes it useful for the construction of missiles and satellites. Beryllium is also used as windows for x-ray tubes because Be atoms have so few electrons, thin sheets of the metal are transparent to x-rays and allow the rays to escape. Beryllium is added in small amounts to copper the small Be atoms pin the Cu atoms together in an interstitial alloy that is more rigid than pure copper but still conducts electricity well. These hard, electrically conducting alloys are formed into nonsparking tools for use in oil refineries and grain elevators, where there is a risk of explosion. Beryllium-copper alloys are also used in the electronics industry to form tiny nonmagnetic parts and contacts that resist deformation and corrosion. [Pg.713]

Aluminum s low density, wide availability, and corrosion resistance make it ideal for construction and for the aerospace industry. Aluminum is a soft metal, and so it is usually alloyed with copper and silicon for greater strength. Its lightness and good electrical conductivity have also led to its use for overhead power lines, and its negative electrode potential has led to its use in fuel cells. Perhaps one day your automobile will not only be made of aluminum but fueled by it, too. [Pg.719]

Each step in dendrimer synthesis occurs independent of the other steps therefore, a dendrimer can take on the characteristics defined by the chemical properties of the monomers used to construct it. Dendrimers thus can have almost limitless properties depending on the methods and materials used for their synthesis. Characteristics can include hydrophilic or hydrophobic regions, the presence of functional groups or reactive groups, metal chelating properties, core/shell dissimilarity, electrical conductivity, hemispherical divergence, biospecific affinity, photoactivity, or the dendrimers can be selectively cleavable at particular points within their structure. [Pg.346]

The major function of a bipolar plate, or simply called "plate," is to connect each cell electrically and to regulate the reactant gas (typically, hydrogen and air in a hydrogen fuel cell) or reactant liquid (typically, methanol in a DMFC) and liquid or gas coolant supply as well as reaction product removal in desired patterns. This plate must be at least electrically conductive and gas and/or liquid tightened. Considering these important functions and the larger fraction of volume, weight, and cost of the plate in a fuel cell, it is worthwhile to construct this chapter with emphasis on the current status and future trend in bipolar plate research and development, mainly for the plate materials and fabrication process. [Pg.306]

To obtain semiconductors with magnetic properties, Fujiwara et al. (2003) developed several donor molecules containing a stable oxyl radical moiety based on the n-extended TTF framework. The TTF framework is too small to overcome the steric hindrance of the bulky nitroxyl radical and to accomplish strong intermolecular interaction indispensable for any electric conductivity. For this reason, a larger molecule was constructed and its cation-radical perchlorate was electrochemically prepared. This salt was obtained as black microcrystals of nonstoichiomteric ratio equal to 1 0.64. Being a semiconductor, the salt also manifests magnetic properties its structure is depicted in Scheme 8.13. [Pg.419]

Technically important electrochemical reactions of pyrrole and thiophene involve oxidation in non-nucleophilic solvents when the radical-cation intermediates react with the neutral molecule causing polymer growth [169, 191], Under controlled conditions polymer films can be grown on the anode surface from acetonitrile. Tliese films exhibit redox properties and in the oxidised, or cation doped state, are electrically conducting. They can form the positive pole of a rechargeable battery system. Pyrroles with N-substituents are also polymerizable to form coherent films [192], Films have been constructed to support electroactive transition metal centres adjacent to the electrode surface fomiing a modified electrode,... [Pg.224]

An alternate procedure for 100 to 200g batches used a Cradle-Roll Mixer. This device consisted of a half-barrel type container constructed of wood and lined with an electrical conductive material. A plastic roll was allowed to move over the ingredients by remote control action. The roll action prevented caking of the mixt but had no adverse effect on particle size of the ingredients. The period of time to obtn an intimate mixt was approx 15 mins... [Pg.73]

Among other electrical properties of nitrocellulose, attention should be paid to the experimental work on the electrical conductivity of solutions. Thus Dobry [143] found the conductivity of a nitrocellulose solution in acetone to be proportional to its concentration. Experiments on the electrophoresis of solutions made by Lantz and Pickett [144] demonstrated that the particles of nitrocellulose carry a negative charge. Electrolysis of the solution causes the nitrocellulose gel to collect at the anode. This gel may contain the metal of which the anode is constructed, as demonstrated byApard [145]. [Pg.288]

With the introduction of the lattice structure and electroneutrality condition, one has to define two elementary SE units which do not refer to chemical species. These elementary units are l) the empty lattice site (vacancy) and 2) the elementary electrical charge. Both are definite (statistical) entities of their own in the lattice reference system and have to be taken into account in constructing the partition function of the crystal. Structure elements do not exist outside the crystal and thus do not have real chemical potentials. For example, vacancies do not possess a vapor pressure. Nevertheless, vacancies and other SE s of a crystal can, in principle, be seen , for example, as color centers through spectroscopic observations or otherwise. The electrical charges can be detected by electrical conductivity. [Pg.21]

A third type of security glass is installed in modem penal institutions. This product is utilized for prisoner detention and obviates iron bars and their demeaning aspect. Typical construction utilizes three or more layers with at least one ply of thick PVB. Other constructions utilize polycarbonates, polyurethanes, and modified acrylics. Strengthened glass and electrically conductive circuits for alarms may be included. Large, heavy sections of similar construction have been used for underwater windows for boats, submarines, and aquariums. Four plies of fully tempered, 10-mm glass plus three plies of PVB totaling 44.5 mm in thickness has a modulus of rupture of 172 MPa (25,000 psi) (39). [Pg.529]


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See also in sourсe #XX -- [ Pg.62 ]




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Electrical conductivity, construction materials

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