Combination Of Nickel Research Articles

Pyrolysis and hydropyrolysis of amberlite IRC50 and some of its metal-exchanged forms

As a model for part of the structure of low-rank coals, a cation exchange resin (Amberlite IRC50) and several of its metal-exchanged forms were studied by differential thermal analysis in nitrogen and in high-pressure hydrogen, and also by simultaneous thermogravimetry and mass spectrometry. The pyrolysis temperatures decreased in the sequence: Na ⪢ Ba ⪢ Ca ⪢ Zn ⪢ Co ⪢ Bi ⪢ Sn ⪢ Pb ⪢ Fe ⪢ Ni. The presence of high-pressure hydrogen complicated the results for the reducible metals. Because the peak temperature of the lead form was similar to those of iron, nickel and tin, which are known to catalyse hydrogenation reactions, it is concluded that lead is worthy of investigation as a potential catalyst for coal hydrogenation. The combination of nickel and cobalt, and of lead and iron appear to act synergistically in hydrogen, so they too may be effective catalyst combinations. Since sodium, potassium and calcium occur commonly in low-rank coals, they may inhibit the onset of decomposition reactions during processing at typical coal-processing temperatures of about 400°C.

Steric selectivity in oxidations of diols

Oxidations of 2,2-disubstituted-1,4-butanediols by the combination of nickel(II) bromide and benzoyl peroxide and by trityl tetrafluoroborate produce β,β-disubstituted-γ-butyrolactones with exceptional selectivity.

Selective Oxidations of Alcohols by Bromine in Combination with Nickel(II) Benzoate

Abstract The combination of nickel(II) bromide with benzoyl peroxide serves as an effective reagent for the conversion of secondary alcohols to ketones and, when nickel(II) bromide is employed as an alcohol template, for the oxidation of primary alcohols to aldehydes.1 The unique steric selectivity of the Bz2O2/NiBr2 combination has recently been demonstrated in oxidations of 2,2-disubstituted-1, 4-butanediols to the corresponding β,β-disubstituted-γ-butyrolactones.2 In the course of our investigation of this novel oxidative method, we have discovered that molecular bromine in combination with commercially available nickel(II) benzoate is a mild, effective, and selective oxidant for the conver-

A Facile Desulfurization Reaction with a Combination of Two Kinds of Metals in Acidic Media. The Synthesis of Hypoxanthine

Abstract A facile desulfurization procedure has been presented for the method that synthesizes hypoxanthine in one step by heating 4,5-diamino-6-hydroxy-2-mercaptopyrimidine with a desulfurizing agent in formic acid. When Raney nickel prepared in the usual way was used as the desulfurizing agent, it was necessary for the ratio of nickel atoms to sulfur atoms (the Ni/S ratio) to be more than 2.6 : 1. On the contrary, when the Raney alloy per se was used, the amount of nickel could be diminished to a catalytic amount (Ni/S 0.2–0.3). The higher the content of aluminum in the alloy, the smaller the Ni/S ratio required for the desulfurization. In contrast with usual desulfurization reactions carried out in neutral media, most of the sulfur was released from the reaction mixture as hydrogen sulfide. Although aluminum or iron powder by itself had little desulfurizing activity, its addition to the Raney alloy was useful in diminishing the Ni/S ratio. Furthermore, combinations of nickel or cobalt salts and aluminum or iron powder were as effective as the Raney alloy as desulfurizing catalysts. In the case of a combination of nickel formate and aluminum powder, a large portion of the nickel ion was proved to be reduced to metallic nickel. The desulfurization reaction also proceeded smoothly in an aqueous solution of hydrochloric or sulfuric acid. On the basis of these facts, a mechanism was proposed with which the active nickel catalyst is regenerated by such auxiliary metals as aluminum or iron.

The electronic structure and electron spin resonance of tricyclopentadienyl trinickel dicarbonyl

The electronic structure of the paramagnetic molecule (C5H5)3Ni3(CO)2 is investigated, and the odd electron is assigned to an A 2″ combination of nickel d orbitals. The g values of the molecule are calculated on this hypothesis and are found to be consistent with the experimental values.

Corrosion-Resistant Experimental Steels For Marine Applications

Abstract Six steels having various combinations of nickel, copper and phosphorous were tested in sea water for exposure periods of one, two and five years, and a comparison made with the corrosion resistance of structural carbon steel. The test specimens measured 20 feet in length and were placed in the sea water so that their tops extended above the splash zone while the bottoms were in the mud. Decreases in thickness were calculated at 20 different levels for each of the Ni-Cu-P steels. It was found that these steels as a class were much more corrosion resistant than the sheet-piling steel to the conditions existing in and above high tide. The superiority was even greater when the steels were exposed to the atmosphere 80 feet from shore. The five-year exposure tests showed that steel containing 0.5 percent Ni, 0.5 percent Cu and 0.12 percent P had the greatest resistance of the steels tested. The attack below low tide was essentially independent of the composition of the steel. Pitting attack was very l...

A NICKEL–ALUMINUM–MOLYBDENUM CREEP RESISTANT ALLOY

This paper describes a preliminary study of alloys of nickel and aluminum modified with molybdenum. The purpose of this work is to develop an alloy for use under conditions of stress at temperatures of 815 °C. (1500° F.) and over. The room temperature mechanical properties of alloys of nickel and aluminum, and the influence of molybdenum on these properties, have been investigated. Certain combinations of nickel, aluminum, and molybdenum have been shown to possess tensile strengths well over 100,000 lb. per sq. in. at room temperature, and it has been demonstrated that certain characteristic microstructures, dependent upon the ratio of nickel to aluminum, are essential for the realization of these high strengths. Creep-rupture tests at 815 °C. (1500° F.) have been carried out on typical nickel–aluminum–molybdenum alloys. The results have shown that certain of these alloys are superior in many respects to existing high temperature alloys, when tested under creep-rupture conditions at 815 °C. (1500° F.). The same characteristics of microstructure that are essential for high room temperature strengths were also found to be necessary to obtain good creep-rupture characteristics at 815 °C. (1500° F.).

Influence of Chemical Composition and Heat Treatment of Steel Forgings on Machinability With Shallow Lathe Cuts

Abstract The tests described in this report were made primarily as a study of lathe-tool performance with shallow cuts as affected by variations in chemical composition and heat treatment of the steels cut. The cutting tests were made dry with high-speed-steel tools of a selected size, form, composition, and heat treatment, with a feed of 0.0115 in. per rev. and 0.010 in. depth of cut. Comparisons were made of the Taylor speeds on the basis of equal tensile strengths when cutting 0.4 per cent carbon (S.A.E. 1040), chromium-vanadium (S.A.E. 6140), nickel-chromium (S.A.E. 3140 and 3435), chromium-molybdenum (S.A.E. 4140), and 3½ per cent nickel (S.A.E. 2340) steel forgings heat treated to give tensile strengths between 75,000 and 220,000 lb. per sq. in. The study also included consideration of the surface finishes of the various steel forgings as affected by the test conditions, the microstructures of the steels cut, and tool performance as affected by the additions of 3.5 to 11.7 per cent cobalt to the customary 18 per cent tungsten type of high-speed tool steel. If machinability is measured by the cutting speed permitting the tools to last a definite time, then measurable differences were observed between the various steels cut in the lathe test with shallow cuts. The fact, however, that some given steel permits a higher cutting speed than another steel for some tensile strength which is the same for both materials does not necessarily indicate that the two steels maintain the same relationship for another tensile strength. Of the different steels cut in the lathe tests, the plain carbon steel was the most difficult to machine other than an annealed nickel-chromium steel. The surface finish on the plain carbon steel was also considered to be inferior to the surface finish of the alloy steels. The results showed that the effect of changes in chemical composition of steel forgings upon their cutting speeds was dependent upon the tensile strength at which the comparisons were made. In the different steels cut with shallow cuts the most effective special alloying elements for improving machinability were the combinations of nickel and chromium or chromium and vanadium for the high tensile strengths in the neighborhood of 180,000 lb. per sq. in., while chromium and molybdenum were the most effective in the lower range of about 90,000 lb. per sq. in.