Miscellaneous materials

Complex lithium halide spinels (Kanno, Takeda and Yamamoto, 1982 Lutz, Schmidt and Haeuseler, 1981), based on Li2CdCl4 and Li2MgCl4 have remarkably high Li ion conductivity for close packed structures. Fig. 2.11. These are complicated materials however, they have essentially inverse spinel structures but may exist also in various distorted forms. Some of them undergo a phase transition to defect rock salt structures at high temperatures some are non-stoichiometric. 

The high temperature, a polymorph of Li2S04 has a very high Li ion conductivity, 1 Scm between 575 °C and the melting point, 870 °C. Many attempts have been made to dope Li2S04 and stabilise the highly conducting a polymorph to lower temperatures but these have met with limited success (Lunden, 1987) transformation to the low conductivity P polymorph, or other low conductivity phases, always occurs when the temperature decreases below 500 °C. 

The conduction mechanism in a-Li2S04 is of considerable interest and is a matter of some controversy (Lunden and Thomas, 1989). The uncertainty focuses on whether the sulphate groups are fixed or whether they can rotate and, if they can rotate, whether the lithium ion conductivity 

The same considerations used for insulators and conductors described in the previous sections are applicable to miscellaneous items such as tubing, gaskets, seals, and specialized materials such as adhesives and shells. In low-temperature drift tubes with handheld analyzers, unions for tubing and pump seals and other connections are made using plastics. In research-grade analyzers, connections are usually made with pipe-pipe compression unions or silver-soldered connections. However, material consideration may not be ignored for other parts of a drift tube since even small sources of contamination can render ultrasensitive analyzers, such as IMS drift tubes, unworkable. 

Drift tubes under a slight pressure drop must be engineered with seals and gaskets to prevent inflow of surrounding atmosphere into the drift tube. This can be accomplished with thermoplastics or metal-to-metal seals when elevated temperatures are 

Karasek, F.W., Plasma chromatography—a new dimension for gas chromatography and mass spectrometry, J. Chromatogr. Sci. 1970, 8, 330-337. 

Tunable selective detection for capillary gas chromatography by ion mobility spectrometry. Ami. Chem. 1982, 54, 38-43. 

Schuetze, F.J. Frame, J.M. Hfll, H.H., Jr., A microprocessor controlled ion mobihty spectrometer for selective and nonselective detection following gas chromatography, Am. Lab. 1982, 14, 59-70. 

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TABLE 12-15 Experimental Through-Circulation Drying Data for Miscellaneous Materials... 

Natural rubber displays the phenomenon known as natural tack. When two clean surfaces of masticated rubber (rubber whose molecular weight has been reduced by mechanical shearing) are brought into contact the two surfaces become strongly attached to each other. This is a consequence of interpenetration of molecular ends followed by crystallisation. Amorphous rubbers such as SBR do not exhibit such tack and it is necessary to add tackifiers such as rosin derivatives and polyterpenes. Several other miscellaneous materials such as factice, pine tar, coumarone-indene resins (see Chapter 17) and bitumens (see Chapter 30) are also used as processing aids. 

Other miscellaneous materials also used occasionally include fire retardants, optical bleaches and blowing agents. 

Table 3.4. Electrode potentials of zero lyte solutions. ) charge of miscellaneous materials in contact with aqueous electro- ...

The choice of the filter medium is often the most important consideration to ensure efficient operation of a filter. Its function is generally to act as a support for the filter cake, while the initial layers of cake provide the actual filter. The filter medium should be selected primarily on the basis of its ability to retain solids without binding. It should be mechanically strong and corrosion resistant, and should offer as little resistance as possible to the flow of the filtrate. The media are made from widely different materials such as cotton, wool, linen, nylon, jute, silk, glass fiber, porous carbon, metals, rayon and other synthetics, and miscellaneous materials like porous rubber. Cotton fabrics are most commonly used because they are available in a wide variety of weaves, and are cheap. 

Under this heading are included all the miscellaneous materials required to operate the plant that are not covered under the headings raw materials or maintenance materials. Miscellaneous materials will include ... 

An accurate estimate can be made by detailing and costing all the items needed, based on experience with similar plants. As a rough guide the cost of miscellaneous materials can be taken as 10 per cent of the total maintenance cost. 

Variable costs 1. Raw materials 2. Miscellaneous materials 3. Utilities 4. Shipping and packaging Typical values from flow-sheets 10 per cent of item (5) from flow-sheet usually negligible... 

Applications to Inorganic and Miscellaneous Materials, Handbook of Thermal Analysis and Calorimetry, vol. 2, Elsevier, Amsterdam. 

J.C. Oxley, The Thermal Stabihty of Explosives Chapter 8 in Handbook of Thermal Analysis and Calorimetry Applications to Inorganic and Miscellaneous Materials Volume 2 , P.K. Gallagher and M.E. Brown, eds, Elsevier p. 349—369. Elsevier Amsterdam. 

It can also be used for rapid detn of small amts of water in miscellaneous materials. The KF reagent consists of sulfur dioxide-iodine in pyridine-methanol solution. It is available in commerce in strength equivalent to 5—6 mg water per 1 ml of reagent. It can also be prepd... 

Fluorine Miscellaneous materials, 4304 Magnesium perchlorate Cellulose, etc., 4078 /V-Meth yI morpholine oxide, 1991 Nitric acid Cellulose, 4430 Perchloric acid Cellulose and derivatives, 3992 Perchloric acid Hydrofluoric acid, Structural materials, 3992 Potassium chlorate Cellulose, 4011 Potassium nitrate Cellulose, 4645 Sodium chlorate Paper, etc., or Wood, 4033 Sodium nitrate Fibrous material, 4716 Sodium nitrite Wood, 4715 Sodium peroxide Fibrous materials, 4797 Zinc permanganate Cellulose, 4705 BLEACHING POWDER Wood perchlorates Organic matter See SUGARS... 

Brewer, L., Chemistry and Metallurgy of Miscellaneous Materials Thermodynamics , paper 7... 

Miscellaneous Materials Thermodynamics , paper 6 (L. L. Quill, ed.), McGraw-Hill Publications, New York, 1950. 

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