Oxidation classes

Extractants derived from the carbamoylmethylphosphoryl moiety (CMP) were studied in the phosphonate, phosphinate, and phosphine oxide classes. Our studies focused on dihexyl-N,N-diethylcarba-moylmethylphosphonate, DHDECMP, hexyl hexyl-N,N-diethylcarbamoyl-methylphosphinate, HHDECMP, and octyl(phenyl)-N,N-diisobutylcarba-moylmethylphosphine oxide, 0D[ IB]CMP0. The three types of CMP extractants were compared on the basis of nitric acid and extractant dependencies for Am(III), solubility of complexes on loading with Nd(III) and U(VI), and selectivity over fission products. On the basis of the above data two conceptual flowsheets were developed. The first flowsheet involves the extraction of all of the actinides from HLLW using 0.4 M 0D[IB]CMP0 in DEB. The second flowsheet involves the extraction of all of the actinides from dissolved spent LWR fuel using 0.8 M DHDECMP in DEB. 

The potential for violence of interaction between the powerful reducing agent potassium and oxidant classes has been well described. Other miscellaneous oxygen-containing substances which react violently or explosively include sodium iodate, silver iodate, lead sulfate and boric acid. 

Electroneutrality in the lattice is ensured by reduction of An to An, since for all the actinides in the hypostoichiometric oxide class, the trivalent state is stable (see Fig. 1 in Chap. A). 

Neutral Oxides, Class I.—The next neutral oxides met with are carbon monoxide, CO, nitrous oxide, N20, and nitric oxide, NO. These are all gases, but condense at low temperatures to colourless liquids, and at still lower, freeze to white solids. 

Neutral Oxides, Class II. — The next class of oxides comprises those which may be termed neutral, because they can act either as bases or as acids, according as they are treated with an acid or with a base. Their hydroxides may be comprised in the same class. A case of this kind has already been explained on p. 70 it is there shown that aluminium hydroxide, when treated with acids, yields salts of aluminium, while with bases aluminates are formed. 

Liquid and solid oxidizers are designated as Class 1, 2, 3, or 4 by NFPA 430, Code for the Storage of Liquid and Solid Oxidizers. Class 1 oxidizers are considered the least hazardous and Class 4 the most hazardous. The behavior of commercially available strengths of liquid and solid oxidizers under storage conditions is the basis for this classification system. This behavior includes fire hazard and reactivity. The acute and chronic health hazards as well as the environmental hazards of liquid and solid oxidizers are not addressed. 

The NFPA 430 classification system, the fire hazard behavior of liquid and solid oxidizers that can increase the burning rate or cause spontaneous ignition of a combustible material. Also, the reactivity behavior of liquid and solid oxidizers includes those that can undergo a self-sustained decomposition or an explosive reaction. The definitions used to define liquid and solid oxidizer classes can be subject to interpretation. The NFPA 430 classification system is based on the Technical Committee s evaluation of available scientific and technical data, actual experience, and it s considered opinion. A listing of typical liquid and solid oxidizers by class can be found in the Appendix of NFPA 430. The oxidizers listed are assumed to be pure materials unless otherwise specified. 

Fly ash starts out as impurities in coal, mostly clay, shales, limestone, and dolomite, which ends up as ash, and fuse at high temperature becoming glass. Two U.S. classifications of fly ash are produced. Class C and Class F, according to the type of coal used. Class C fly ash, typically obtained from subbituminous and lignite coals, must have more than 50% total of silica, alumina, and iron oxide. Class F fly ash, typically obtained from bituminous and anthracite coals, has more than 70% of these oxides. 

The hazard classes recognized by the DOT are Class 1, Explosives Class 2, Compressed Gases Class 3, Flammable Liquids Class 4, Flammable Solids Class 5, Oxidizers Class 6, Poisons Class 7, Radioactives Class 8, Corrosives and Class 9, Miscellaneous Hazardous Materials. Class 1 Explosives are subdivided into six subclasses 1.1 through 1.6. Class 2 Compressed Gases have three... 

Permeation in Other Oxide Classes and the Possibility of Neutral Hydrogen Species... 

OXIDATION CLASS STARTING MATERIAL PRODUCT END USE MILLIONS TON... 

Oxidizers [NOTE Additional requirements can be found in NFPA 430, "Code for Storage of Solid and Liquid Oxidizers", when quantities exceed 4,000 pounds of Class 1 oxidizer (see definition), 1,000pounds of Class 2 Oxidizer (see definition), 200 pounds of Class 3 Oxidizer (see definition), or 10 pounds of Class 4 Oxidizer (see definition). Oxidizer classes are defined in NFPA 430".]... 

Turning to the ternary and quaternary mixed-valency copper oxide class of superconductors, first uncovered by Bednorz and Muller in 1986, the... 

Hazardous substances which are listed as dangerous goods are, as noted earlier, put into one of nine classes. Substances can be given a class on the basis of the main or primary hazard, and a subsidiary class on the basis of another class of hazard. For example, a chemical like red fuming nitric acid may be both corrosive and oxidizing. Class 8 and Class 5. 

Chapter 7 Oxidizers Class 5.1 Oxidizers Oxysalts Peroxide Salts Inorganic Acid Oxidizers Other Oxidizer Componnds Incidents... 

Tlie plienomenon of half-metallicity has gained much interest in order to understand the unusual band structures in various classes of materials and their potential applications in future electronic devices. For example, zinc blend pnictides and chalcogenides e.g. CrAs) are another class of non-oxide materials (apart from Heuslers) in addition to the many oxide classes that are potentially half-metallic materials. Alkali metal doped rare earth oxomanganates, (REi- A MnOs), rutile-Cr02, spinel-Fe304 and Sr2peMo06 double perovskite oxide are examples of important half-metallic oxides. 

Resistance to oxidation - classed according to the temperature range in which the rale of attack by air would cause severe erosion or failure of the coated specimen within a few hours. 1 above l.700i C 2 1.400 to l.700 C 1.100 to l.400 C 4 800 to l.000 C 5 500 to 800 C. Microhardness values taken with lOlHt load. 

Many representatives of the trialkyl orthophosphate ester, dialkyl alkyl (or aryl) phosphonate ester, alkyl dialkyl (or diaryl)-phosphinate, and trialkyl (or triaryl) phosphine oxide class have been investigated. Judging from the reviews available, none of the more exotic types appears to offer any particular advantage over tributyl orthophosphate as a selective extractant for resolving lanthanide mixtures. Most are either viscous liquids or solids that require a diluent, and for the most part the individual separation factors to be had are unspectacular. 

Hazard Classification Class C (Oxidizer), Class D, Div. 2 Subdiv. 

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