Oxidation of completely methylated methyl glycopyranosides by chromic anhydride

1976 ◽  
Vol 25 (3) ◽  
pp. 619-625
Author(s):  
N. K. Kochetkov ◽  
O. S. Chizhov ◽  
A. F. Sviridov ◽  
I. Sent-Kiraii ◽  
V. I. Kadentsev
Keyword(s):  
Chromic Anhydride

Aspects of Applying Hard Chromium Coatings on the Inner Surfaces of Components for Hydraulic Drives with Hydrostatic Guideways

2021 ◽  
Vol 316 ◽  
pp. 827-832
Author(s):  
D. V. Ardashev ◽  
L.V. Shipulin ◽  
A.S. Degtyareva-Kashutina
Keyword(s):  
Hydraulic Cylinder ◽  
Chromium Coating ◽  
Optimal Composition ◽  
Chromic Anhydride ◽  
Corrosion Resistant ◽  
Distinctive Features ◽  
Wear Resistant Coatings ◽  
Hard Chromium ◽  
Chromium Plating ◽  
Plating Method

We considered the processes of chromium plating the inner surfaces of the components of cylinders with hydrostatic guideways. We demonstrated the various aspects of the chromium plating process – the limitations placed on the machinery depending on the dimensions of the parts to be plated and the unevenness of the deposition rate of chromium along the length of the part. We developed a diagram of an installation for the application of a hard chromium coating on inner surfaces, which includes a cathode, an anode, a tank, and a pipeline. The distinctive features of the installation are the method of supplying the electrolyte at an angle to the horizontal, which allows us to supply the electrolyte through a turbulent flow swirling along a helical path, and the use of a chromium-plated installation casing. We studied various modes for applying a hard chromium coating on the inner surfaces of a hydraulic cylinder. As a result, we determined the optimal composition of the chromium electrolyte – the ratio of chromic anhydride and sulfuric acid – which is 10:1, respectively, and experimentally selected deposition modes. Chromium coatings obtained through the use of the concentrated electrolyte, which we developed, and the chromium plating method have 5...20% greater hardness and a 10...30-times reduction in porosity with the formation of a shiny, lumpy sludge, which corresponds to corrosion-resistant and wear-resistant coatings needed to manufacture hydraulic drives with highly efficient hydrostatic guideways.

scholarly journals Hydrocracking of Yubari residual coal treated with Chromic Anhydride.

1993 ◽  
Vol 72 (10) ◽  
pp. 1022-1026
Author(s):  
Shigeki FURUKAWA ◽  
Yohichi SUZUKI
Keyword(s):  
Chromic Anhydride ◽  
Residual Coal

Addition Compounds of Chromic Anhydride with Some Heterocyclic Nitrogen Bases

1948 ◽  
Vol 70 (11) ◽  
pp. 3827-3830 ◽  
Author(s):  
Harry H. Sisler ◽  
Jack D. Bush ◽  
Oliver E. Accountius
Keyword(s):  
Chromic Anhydride ◽  
Heterocyclic Nitrogen ◽  
Nitrogen Bases

Oxidation of aldehydes to acyl azides by chromic anhydride-azidotrimethylsilane

1992 ◽  
Vol 33 (22) ◽  
pp. 3165-3166 ◽  
Author(s):  
Jong Gun Lee ◽  
Ki Hoon Kwak
Keyword(s):  
Chromic Anhydride ◽  
Acyl Azides

An acid process for the production of chromic anhydride from chromite ore

1950 ◽  
Vol 69 (9) ◽  
pp. 275-282 ◽  
Author(s):  
J. L. Clay ◽  
J. F. Pearse ◽  
D. H. Trethewey
Keyword(s):  
Chromic Anhydride ◽  
Chromite Ore ◽  
Acid Process

Compounds of chromium(VI): The pyridine – chromic anhydride complex, benzimidazolinium dichromate, and three 2-alkyl-1H-benzimida -zolinium dichromates

2003 ◽  
Vol 81 (6) ◽  
pp. 612-619 ◽  
Author(s):  
T Stanley Cameron ◽  
Jason AC Clyburne ◽  
Pramod K Dubey ◽  
J Stuart Grossert ◽  
K Ramaiah ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Chromium Trioxide ◽  
Aqueous Acetic Acid ◽  
Secondary Alcohols ◽  
Chromic Anhydride ◽  
Acid Base ◽  
Chromium Vi ◽  
Oxidation Of Alcohols ◽  
Dichromate Anions

Pyridine, when allowed to react with chromic anhydride under strictly anhydrous conditions, gives the known, very air-sensitive, crystalline 2:1 Lewis acid–base complex 1. The crystal structure has now been successfully determined. When benzimidazole and three 2-alkyl-1H-benzimidazoles were treated with chromium trioxide in aqueous acetic acid, crystalline dichromate salts (2–5) were readily formed. These salts consist of dichromate anions linked to the cations by hydrogen bonds of the type N—H···O. The chromium atoms have distorted tetrahedral environments, with the Cr—O distances being typical for dichromate anions. In the cases of the 2-methyl and 2-ethyl salts, the anions are disordered about a centre of inversion. The hydrogen bonding arrangements are discussed and the structures are compared with other oxygenated chromium(VI) species. The dichromate salts are useful selective oxidants for a range of primary and secondary alcohols; examples of these reactions are reported.Key words: chromium(VI), pyridine – chromium trioxide complex, benzimidazolinium dichromate salts, controlled oxidation of alcohols.

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