Container material

Carbon dioxide, COj. Sublimes — 78 5 C. A colourless gas at room temperature, occurs naturally and plays an important part in animal and plant respiration. Produced by the complete combustion of carbon-containing materials (industrially from flue gases and from synthesis gas used in ammonia production) and by heating metal carbonates or by... 

A very important but rather complex application of surface chemistry is to the separation of various types of solid particles from each other by what is known as flotation. The general method is of enormous importance to the mining industry it permits large-scale and economic processing of crushed ores whereby the desired mineral is separated from the gangue or non-mineral-containing material. Originally applied only to certain sulfide and oxide ores. 

Calcium plays an important part in structure-building in living organisms, perhaps mainly because of its ability to link together phosphate-containing materials. Calcium ions in the cell play a vital part in muscle contraction. 

Copper(II) ions in aqueous solution are readily obtained from any copper-containing material. The reactions with (a) alkali (p. 430), (b) concentrated ammonia (p 413) and (c) hydrogen sulphide (p. 413) provide satisfactory tests for aqueous copper(II) ions. A further test is to add a hexacyanoferrate(II) (usually as the potassium salt) when a chocolate-brown precipitate of copper(II) hexacyanoferrate(II) is obtained ... 

Silver has little tendency to formally lose more than one electron its chemistry is therefore almost entirely restricted to the + 1 oxidation state. Silver itself is resistant to chemical attack, though aqueous cyanide ion slowly attacks it, as does sulphur or a sulphide (to give black Ag S). hence the tarnishing of silver by the atmosphere or other sulphur-containing materials. It dissolves in concentrated nitric acid to give a solution of silver(I) nitrate. AgNOj. 

Manufacture. Boron trifluoride is prepared by the reaction of a boron-containing material and a fluorine-containing substance in the presence of an acid. The traditional method used borax, fluorspar, and sulfuric acid. 

Renewable carbon resources is a misnomer the earth s carbon is in a perpetual state of flux. Carbon is not consumed such that it is no longer available in any form. Reversible and irreversible chemical reactions occur in such a manner that the carbon cycle makes all forms of carbon, including fossil resources, renewable. It is simply a matter of time that makes one carbon from more renewable than another. If it is presumed that replacement does in fact occur, natural processes eventually will replenish depleted petroleum or natural gas deposits in several million years. Eixed carbon-containing materials that renew themselves often enough to make them continuously available in large quantities are needed to maintain and supplement energy suppHes biomass is a principal source of such carbon. 

C or higher for the kaolin-based products to 1425°C and above for the zirconium-containing materials. At temperatures above 1000°C these ceramic fibers tend to devitrify and partially crystallize. Specially prepared ceramic fibers are used to protect space vehicles on re-entry and can withstand temperatures above 1250°C (see Ablative materials Refractory fibers). 

Mineral oil and paraffins should not be used, because these are not metabolized and may irritate tissue. Various other additives are needed for stabiUty, stefihty, and isotonicity antimicrobial preservatives, antioxidants (qv), chelating agents (qv), and buffers. No parenteral container material is completely inert to parenteral solvent systems. 

Smaller amounts of phosphoms, or elemental phosphoms-containing materials, are also shipped in 115-L (30-gal) dmms that are DOT regulated (U.S. DOT lAl or 1A2 classification) and have thick shells and special gaskets and fittings for protection. Quantities up to 0.5 kg (1 lb) are allowed for shipping in two hermetically sealed (soldered), nested cans inside a wooden box where the empty space is filled with vermiculite (U.S. DOT 4C1, 4C2, 4D, or 4F classification). AH air transportation of elemental P, both U.S. and international, was prohibited beginning in 1992. 

The amount of impurities present in the 2inc sulfate solution is determined by the local source of 2inc-containing material used in the above reaction. To get a good quaUty Hthopone, the impurities must be removed from the solution. 

As with SMC, appHcations are limited to high volume because of the capital investment in equipment and tooling. Thermoset compression molders require additional heating and material Handling equipment to adapt their process to thermoplastic sheet fabrication. AppHcations include automotive bumper beams, load floors, radiator supports, battery trays, and package shelves. Chair sheUs, military containers, material Handling pallets, trays, and concrete foaming pans are also produced. 

Ion implantation has been successfully used to dope the IITSb material system. Sulfur has been used as an n-ty e dopant, although with poor activation efficiencies (175). -Type doping has been achieved using beryUium, zinc, and magnesium (175,176). Activation of the -type dopants is generally much better, near 50%. For the Sb-containing materials the post-implant anneal is conducted at much lower temperatures, typically <600° C. 

The oxidation of vitreous siUca appears to proceed by one of two mechanisms, depending on the material s hydroxyl content (109,111). In hydroxyl-containing material, the rapid oxidation probably occurs by the diffusion and removal of hydrogen, according to the following reaction ... 

Because branched ketones and aromatic hydrocarbons are used for their cost/performance benefits, they became the solvents of choice for many apphcations. Numerous solvent systems had to be reformulated to comply with Rule 66. This usually meant an increase in cost, sometimes accompanied by performance degradation. Rule 66-type regulations were adopted in many other states and cities as well. Federal specifications for coatings and many other solvent-containing materials also incorporate Rule 66 requirements. 

Thiols iateract readily with many mbber-containing materials. For this reason, care should be taken ia the selection of gasket and hose materials. Teflon, Kel-F, Viton, or other suitable fluoroelastomers function as gasket materials. Viton is suitable for hoses. Carbon steel is useful for many thiols, although some thiols become very discolored when carbon steel is utilized. In these cases, the use of stainless steel is very desirable. Isolation from air and water also minimizes color formation. 2-Mercaptoethanol and 1,2-ethanedithiol should be stored ia stainless steel (61). 

A tinplate container has an energy advantage over some of the competitive container materials, as shown in Table 6. By virtue of its magnetic properties, tinplated material is more readily separated by other forms of industrial or domestic waste. 

Because no process has been developed for selectively removing impurities in vanadium and vanadium alloys in the metallic state, it is essential that all starting materials, in aggregate, be pure enough to meet final product purity requirements. In addition, the consoHdation method must be one that prevents contamination through reaction with air or with the mold or container material. 

Because of the strategic nature of many of the uses, vanadium is one of the materials designated in the National Defense Stockpile Inventory. The goals for 1980 for vanadium-containing materials was 907 metric tons of contained vanadium in ferrovanadium, and 6985 t of contained vanadium in vanadium pentoxide. As of March 1981, the inventory consisted of 4911 of contained vanadium in vanadium pentoxide there was no ferrovanadium in the inventory (22). 

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