Tine oxides

The S. and C. composition varies, according to whether it it to be used for paralfined or sulphured splints, or for waxed threids. The ordinary composition is as follows —6 parts of phosphorus sesquisulj de, 34 parts of potassium chlorate, 6 parts of tine oxide (zinc white), 6 parts of red ochre, 6 parts of powdered glass, 6 parts of glue, and 34 parts of water. It is easy, by manipulation, to make these matches either more or less inflammable. The mechanical processes are much the tame as in the manufacture of phosphorous matches. 

Other techniques include oxidative, steam atmosphere (33), and molten salt (34) pyrolyses. In a partial-air atmosphere, mbber pyrolysis is an exothermic reaction. The reaction rate and ratio of pyrolytic filler to ok products are controlled by the oxygen flow rate. Pyrolysis in a steam atmosphere gives a cleaner char with a greater surface area than char pyroly2ed in an inert atmosphere however, the physical properties of the cured compounded mbber are inferior. Because of the greater surface area, this pyrolytic filler could be used as activated carbon, but production costs are prohibitive. Molten salt baths produce pyroly2ed char and ok products from tine chips. The product characteristics and quantities depend on the salt used. Recovery of char from the molten salt is difficult. 

In the depolymeri2ed scrap mbber (DSR) experimental process, ground scrap mbber tines produce a carbon black dispersion in ok (35). Initially, aromatic oks are blended with the tine cmmb, and the mixture is heated at 250—275°C in an autoclave for 12—24 h. The ok acts as a heat-transfer medium and swelling agent, and the heat and ok cause the mbber to depolymeri2e. As more DSR is produced and mbber is added, less aromatic ok is needed, and eventually virtually 100% of the ok is replaced by DSR. The DSR reduces thermal oxidation of polymers and increases the tack of uncured mbber (36,37). Depolymeri2ed scrap mbber has a heat value of 40 MJ/kg (17,200 Btu/lb) and is blended with No. 2 fuel ok as fuel extender (38). 

Nasr et failed to observe a change in the ratio of NADPH to NADP in the tracheal epithelium of rats exposed to ozone at 33 ppm for an hour. This apparently negative in vivo finding is not surprising, inasmuch as NADP will be rapidly reduced back to NADPH if ozone does not disrupt the structural integrity of pyridine nucleotides. In addition, de novo thesis of pyridine nucleotides may also occur. The intracellular ratio of reduced to oxidized pyridine nucleotides is under tine cellular control, in that the oxidation of NADPH or NADH results in the stimulation of enzymatic activity, which restores the initial ratio. In the case of NADPH, its oxidation increases the activity of the hexose monophosphate shunt this also occurs after the oxidation of glutathione. The rel-... 

Accdg to Daniel (Ref 1), when a sola of platiriic oxide in sulfuric acid was treated with an excess of aq ammonia. a black ppt of pla-tine fulminant was obtd. When dry it detonated violently by shock, friction and heat (at 160°). Some scientists consider it. as being identical with the nitride (azoture, in Fr)... 

Oeeurrenee.— In nature as oxide (2SaO) in red tine, as sulphide (ZbS") in the mineral akte hlende, earbonate(OOZno")... 

WicholB and Ingham1250 have published kinetic studies involving addition of CNS ions to a large assortment of substituted ethyk-m-oxides. Among the substances examined in tine connexion worn epihalohydrins, glyddo) and its derivatives, and others (Eq. t>77). Terminal addition appeared to take place preponderantly, if u .L exclusively, in every oase. 

Arsenic sublimes on heating and is unchanged in dry air, but a film of oxide is formed in moist air heated in air at 180°C, arsenic forms arsenic trioxide of tine odor of garlic, poisonous insoluble in HC1 but soluble in concentrated HNOj or concentrated H2SO4 to form arsenic acid soluble in hot NaOH solution healed with chlorine forms arsenic trichloride heated with metals forms metallic arsenides. When arsenic is heated in a tube and tile vapor cooled (1) slowly (that is, in the hot part of the tube) black arsenic is formed, and this form is converted into the gray at 360°C, (2) rapidly (that is. in the cold part of the tube) yellow arsenic is formed, and this form is quickly converted into the gray by the action of light. Yellow arsenic is soluble in CS2,... 

Styrene. Commercial manufacture of this commodity monomer depends on ethylbenzene, which is converted by several means to a low purity styrene, subsequently distilled to the pure form. A small percentage of styrene is made from the oxidative process, whereby ethylbenzene is oxidized to a hydroperoxide or alcohol and then dehydrated to styrene, A popular commercial route has been tine alkylation of benzene to ethylbenzene, with ethylene, after which the crude ethylbenzene is distilled to give high purity ethylbenzene. See also Styrene. 

Linear ethoxylates are tine preferred raw materials for production of ether sulfates used in detergent formulations because of uniformity, high purity, and biodegradahility, The alkyl chain is usually in the C y. to Cy range having a molar ethylene oxide alcohol ratio of anywhere from 1 1 to 7 1. Propoxylates, ethoxylates, and mixed alkoxylates of aliphatic alcohols or alkyl phenols are sulfated for use in specialty applications. 

A major zinc ore is ZnS (sphalerite) which frequently occurs with the major lead ore PbS (galena). The lead-zinc ores usually contain recoverable quantities of copper, silver, antimony, and bismuth as well, Major deposits of this type are wmrked in Australia, tine United States, Canada, Mexico, Peru, the former Yugoslav Republics, and the former Soviet Union, Two other important zinc ores are 7nCO i (smithsonite) and iron-zinc-manganese oxide (franklimte). Several of these minerals are described under separate alphabetical entries,... 

Several operations may be employed to treat water prior to use. Aeration is used to drive off odorous gases, such as H2S, and to oxidize soluble Fe2+ and Mn2+ ions to insoluble forms. Lime is added to remove dissolved calcium (water hardness). A12(S04)3 forms a sticky precipitate of Al(OH)3, which causes very tine particles to settle. Various filtration and settling processes are employed to treat water. Chlorine, Cl2, is added to kill bacteria. Formation of undesirable byproducts of water chlorination may be avoided by disinfection with chlorine dioxide, C102, or ozone, 03. 

Fk5. 21. Progression of the vibrational tine structure of the photoluminescence spectr um of vanadium oxide catalyst anchored to SiOj at 77 K. Theoretical results from a Franck-Condon analysis (striped bars) and experimental results (solid bars) [reproduced with permission from Patterson et al. (725)]. 

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