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Chain copper

Temperature dependent conductivity studies reveal a metallic character of the salt and the remarkably high conductivity of 500000 S/cm at 3.5 K. It should be noted that the TCNQ copper salt is a semiconductor with a room-temperature conductivity of 2x 10 S/cm. The crystal structure of the salt TCNQI 2Cu reveals segregated columns formed from the quinone and the copper ion whereby the copper chains are surrounded by 4 quinone stacks [344]. [Pg.66]

The first work published in this area was that of Bigelow mentioned above [116], In 1957, monolayers of long-chain fatty acids were fonned on thin films of silver, copper, iron and cadmium deposited on glass microscope slides [43],... [Pg.2623]

Although many variations of the cyclohexane oxidation step have been developed or evaluated, technology for conversion of the intermediate ketone—alcohol mixture to adipic acid is fundamentally the same as originally developed by Du Pont in the early 1940s (98,99). This step is accomplished by oxidation with 40—60% nitric acid in the presence of copper and vanadium catalysts. The reaction proceeds at high rate, and is quite exothermic. Yield of adipic acid is 92—96%, the major by-products being the shorter chain dicarboxytic acids, glutaric and succinic acids,and CO2. Nitric acid is reduced to a combination of NO2, NO, N2O, and N2. Since essentially all commercial adipic acid production arises from nitric acid oxidation, the trace impurities patterns ate similar in the products of most manufacturers. [Pg.242]

Some metals used as metallic coatings are considered nontoxic, such as aluminum, magnesium, iron, tin, indium, molybdenum, tungsten, titanium, tantalum, niobium, bismuth, and the precious metals such as gold, platinum, rhodium, and palladium. However, some of the most important poUutants are metallic contaminants of these metals. Metals that can be bioconcentrated to harmful levels, especially in predators at the top of the food chain, such as mercury, cadmium, and lead are especially problematic. Other metals such as silver, copper, nickel, zinc, and chromium in the hexavalent oxidation state are highly toxic to aquatic Hfe (37,57—60). [Pg.138]

Apparently the alkoxy radical, R O , abstracts a hydrogen from the substrate, H, and the resulting radical, R" , is oxidized by Cu " (one-electron transfer) to form a carbonium ion that reacts with the carboxylate ion, RCO - The overall process is a chain reaction in which copper ion cycles between + 1 and +2 oxidation states. Suitable substrates include olefins, alcohols, mercaptans, ethers, dienes, sulfides, amines, amides, and various active methylene compounds (44). This reaction can also be used with tert-huty peroxycarbamates to introduce carbamoyloxy groups to these substrates (243). [Pg.131]

A further improvement in the cuprate-based methodology for producing PGs utilizes a one-pot procedure (203). The CO-chain precursor (67) was first functionalized with zirconocene chloride hydride ia THF. The vinyl zirconium iatermediate was transmetalated direcdy by treatment with two equivalents of / -butyUithium or methyUithium at —30 to —70° C. Sequential addition of copper cyanide and methyUithium eUcited the /V situ generation of the higher order cyanocuprate which was then reacted with the protected enone to give the PG. [Pg.162]

Bonding Agents. These materials are generally only used in wire cable coat compounds. They are basically organic complexes of cobalt and cobalt—boron. In wire coat compounds they are used at very low levels of active cobalt to aid in the copper sulfide complex formation that is the primary adherance stmcture. The copper sulfide stmcture builds up at the brass mbber interface through copper in the brass and sulfur from the compound. The dendrites of copper sulfide formed entrap the polymer chains before the compound is vulcanized thus hoi ding the mbber firmly to the wire. [Pg.251]

Oxidation of Straight-Chain Alcohols. Two methods have been developed. One uses an air oxidation catalyzed by a metal, eg, copper, platinum, etc, whereas the other is a caustic oxidation. Generally, however, fatty alcohols are priced higher on the world market than their corresponding fatty acids and, consequently, these conversions are uneconomical. [Pg.92]

Another example of the analogy between pyrazole and chlorine is provided by the alkaline cleavage of l-(2,4-dinitrophenyl)pyrazoles. As occurs with l-chloro-2,4-dinitrobenzene, the phenyl substituent bond is broken with concomitant formation of 2,4-dinitrophenol and chlorine or pyrazole anions, respectively (66AHC(6)347). Heterocyclization of iV-arylpyrazoles involving a nitrene has already been discussed (Section 4.04.2.1.8(i)). Another example, related to the Pschorr reaction, is the photochemical cyclization of (515) to (516) (80CJC1880). An unusual transfer of chlorine to the side-chain of a pyrazole derivative was observed when the amine (517 X = H, Y = NH2) was diazotized in hydrochloric acid and subsequently treated with copper powder (72TL3637). The product (517 X = Cl, Y = H) was isolated. [Pg.268]

This product is pure enough for most purposes. It gives no precipitate with copper sulfate solution, indicating the absence of the open-chain acid. ... [Pg.35]

The oxidation of hydrocarbons, including hydrocarbon polymers, takes the form of a free-radical chain reaction. As a result of mechanical shearing, exposure of ultraviolet radiation, attack by metal ions such as those of copper and manganese as well as other possible mechanisms, a hydrocarbon molecule breaks down into two radicals... [Pg.134]

Chain-breaking antioxidant DLTP Carbon black Copper powder Induction period at 140°C (h)... [Pg.230]

There are concerns that land application of sludge will result in an increase of pathogenic bacteria, viruses, parasites, chemicals and metals in drinking water reservoirs, aquifers, and the food chain. This raises additional concerns of cumulative effects of metals in cropped soils. Research shows that if metals such as zinc, copper, lead, nickel, mercury, and cadmium are allowed to build up in soils due to many applications of sludges over the years, they could be released at... [Pg.573]

FIGURE 21.18 (a) The Cn site of cytochrome oxidase. Copper ligands inclnde two histidine imidazole groups and two cysteine side chains from the protein, (b) The coordination of histidine imidazole ligands to the iron atom in the heme a center of cytochrome oxidase. [Pg.690]

Installation of a different side chain completely alters the pharmacological profile leading to a new class of muscle relaxants. The synthesis begins with copper(II)-promoted di-azonium coupling between furfural (j ) and 3,4-dichlorobenzene-diazonium chloride (15) to give bi aryl aldehyde Next, condensation with 1-aminohydantoin produces the muscle relaxant clodanolene (17). ... [Pg.130]


See other pages where Chain copper is mentioned: [Pg.417]    [Pg.374]    [Pg.706]    [Pg.2488]    [Pg.63]    [Pg.705]    [Pg.2487]    [Pg.169]    [Pg.386]    [Pg.200]    [Pg.417]    [Pg.374]    [Pg.706]    [Pg.2488]    [Pg.63]    [Pg.705]    [Pg.2487]    [Pg.169]    [Pg.386]    [Pg.200]    [Pg.1689]    [Pg.174]    [Pg.27]    [Pg.36]    [Pg.373]    [Pg.385]    [Pg.505]    [Pg.327]    [Pg.220]    [Pg.459]    [Pg.130]    [Pg.357]    [Pg.168]    [Pg.54]    [Pg.43]    [Pg.220]    [Pg.380]    [Pg.264]    [Pg.228]    [Pg.177]    [Pg.1182]    [Pg.1182]    [Pg.1185]    [Pg.1190]    [Pg.1193]   
See also in sourсe #XX -- [ Pg.28 ]




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