Copper oxide needles

A variety of alternative crystal shapes can be produced by forced hydrolysis of inorganic salts. For instance, copper basic sulphate crystals with a uniform leaf-like appearance (Figure 7) can be prepared by heating copper sulphate solutions in the presence of urea (8). Similarly, zinc oxide needles can be obtained by heating zinc nitrate solutions in the presence of triethanolamine (TEA), sodium hydroxide and hydrazine. Figure 8. 

The second category was concerned with adhesion to porous or microfibrous surfaces on metals. Aluminium may be anodised to form an oxide surface comprising pores of diameter of tens of nanometers. Electroforming and chemical oxidation can be used to produce microfibrous or needle-like coatings on metals, including copper, steel and titanium. The substrate topography was demonstrated to play an vital part in adhesion to these surfaces [45-48]. 

Table III permits a cross comparison of Needle Flame and Glow Wire data for modified-polyphenylene oxide. Nickel/polyurethane, copper/epoxy and...

Cu(I) oxide particles of different shapes were obtained by reductive hydrolysis of Cu(II) tartrate solutions in the presence of glucose (107,109) using a process originally described by Andreasen (106). More recently, an extensive study dealt with the precipitation of different copper (hydrous) oxide and oxide particles using controlled double-jet precipitation (CDJP). Thus, depending on experimental conditions, hexagonal platelets or rods of Cu2(0H)3N03 and ellipsoids or needles of CuO... 

Dibenzyl diselenide crystallises from alcohol in yellow needles, which are slightly deeper in colour than those of the p-nitrobenzyl compound, and melt at 92° to 93° C. Exposure to light for an hour or so causes the crystals to turn red. The selenide readily dissolves in hot alcohol, but is only sparingly soluble in ether, insoluble in water. Oxidation with fuming nitric acid converts it into benzyl seleninic acid, and boiling with copper or mercury in suspension precipitates selenium. Boiling with iodine in chloroform solution gives the tetra-iodide, M.pt. 98° C. the tetrabromide melts at 137° C.5... 

As copper is oxidized on the left side, ions enter the solution. The electrons released in the reaction pass through the external circuit from left to right, as shown by the deflection of the ammeter needle. The electrons enter the silver strip, and at the metal-solution interface, they are picked up by Ag" ions, which plate out as atoms on the surface of the silver. This process would lead to an increase of positive charge in the left beaker and a decrease in the right one were it not for the salt bridge the bridge permits a net flow of positive ions through... 

As an alternative 3-[6-(4 -cyanobiphenyl-4-yloxy)hexyl]pyrrole can be oxidized with copper(ll) perchlorate (Care Contact with combustible material may cause fire, irritant) as follows 3-[6-(4 -cyanobiphenyl-4-yloxy)hexyllpyrrole (0.34 g, 1 mmol) is dissolved in acetonitrile (8-10 mL) and added to two-necked round-bottomed flaskfitted with a nitrogen bubbler and a nitrogen gas inlet (e.g. a needle connected to the inert gas supply inserted through a rubber septum). The solution is maintained... 

Cuprous chloride (9.9 g) is dissolved in 30 mL of a 14% solution of ammonia in water, the solution is filtered and water is added until 900 mL of a clear solution is obtained. The solution is cooled with an ice bath, and a stream of 1.4 g (0.027 mol) of cyanoacetylene (1) is swept into the reaction flask by a stream of nitrogen. Copper cyanoacetylide (9) soon begins to precipitate in the form of yellow needles. These are removed by filtration under N2 cover, washed twice with a 1.5% solution of aqueous ammonia, and finally with water. Since dry 9 is an explosive compound, it is used in moist form for the oxidative coupling. 

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