INDEX Cyanides

Entries where the oxidation state of a metal has been specified occur after all the entries for the unspecified oxidation state, and the same or similar entries may occur under both types of heading. Thus cyanide appears under Chromium complexes, Chromium(O) complexes, Chromium(I) complexes, etc. More specific entries, such as Chromium, hexacyano-, may also occur. Similar ligands may also occur in different entries. Thus a carboxylic acid-metal complex may occur under Carboxylic acid complexes, under entries for specific carboxylic acids, and under the specific metal. Coordination complexes may also be listed in the Cumulative Formula Index. 

Cyanide in the body is biotransformed to thiocyanate quickly. People may also be exposed to thiocyanate from dietary, industrial, and medical sources. The plasma concentration of thiocyanate has also been used as an index of long-term exposure to cigarette smoke (Liu and Yun 1993). Some authors have determined thiocyanate in body fluids as a measure of cyanide exposure, while others measure cyanide concentrations in body fluids as a measure of cyanide exposure. 

Several members of this (often endothermic) group of compounds which contain heavy metals tend to explosive instability, and most are capable of violent oxidation under appropriate circumstances. Fusion of mixtures of metal cyanides with metal chlorates, perchlorates, nitrates or nitrites causes a violent explosion [1], Addition of one solid component (even as a residue in small amount) to another molten component is also highly dangerous [2], Individually indexed compounds are ... 

Natural malachite is a dark green crystalline solid monoclinic crystals density 4.0 g/cm refractive index 1.655 decomposes at 200°C insoluble in cold water and alcohols decomposes in hot water soluble in acids, ammonium hydroxide and potassium cyanide solutions. 

White powder cubic crystals the mineral marshite is a red-brown crytal density 5.67 g/cm refractive index 2.346 hardness 2.5 Mohs melts at 606°C vaporizes around 1,290°C insoluble in water and dilute acids soluble in aqueous solutions of ammonia and alkali salts of cyanide, iodide and thiosulfate ions. 

Black monoclinic or hexagonal crystals or powder density 4.6 g/cm refractive index 1.45 hardness 1.8 Mohs decomposes at 220°C insoluble in water, ethanol and aUtabs. Ksp 8.0xl(h34j soluble in nitric acid, ammonium hydroxide and potassium cyanide solutions also soluble in hot hydrochloric and sulfuric acids. 

Orthogonal crystalline powder refractive index (for montroydite) 2.37 density 11.14 g/cm3 Moh s hardness 2.5 insoluble in water and ethanol soluble in dilute acids and aqueous solutions of alkali iodides and cyanides. 

White granular powder or cubic crystals refractive index 2.071 darkens on exposure to hght density 5.56 g/cm Moh s hardness 2.5 melts at 455°C vaporizes at 1,547°C vapor pressure 1 and 5 torr at 912 and 1,019°C insoluble in water, alcohol and dilute acids soluble in ammonia solution and concentrated sulfuric acid, alkali cyanide, ammonium carbonate also soluble in potassium bromide and sodium thiosulfate solutions. 

Metal cyanides are readily oxidised and those of some heavy metals show thermal instability. The covalent cyano group is endothermic, and hydrogen cyanide and many organic nitriles are unusually reactive under appropriate circumstances, and A -cyano derivatives are reactive or unstable. The class includes the groups and individually indexed compounds are f Acetonitrile, 0755 f Acrylonitrile, 1104... 

In the third edition of Richter s formula index (16) each compound has only one place in the compilation, with the exception of the salts, which are placed with the compounds from which they are derived. The chlorides, bromides, iodides, and cyanides of quaternary ammonium bases, however, are entered under the parent compound. 

Benzyloxy(cyano)carbene would be expected to be electrophilic by virtue of the calculated selectivity index, Wp -HjOccN 111- This has not yet been experimentally proved as 3-bcnzyloxy-3-cyano-3//-diazirine is rather labile and cannot be isolated if it is synthesized by the substitution of chlorine by a cyano group in 3-benzyloxy-3-chloro-3if-diazirine consequently, this substitution reaction is carried out in the presence of an alkene, hence, preparing 1-benzyloxy-cyclopropane-l-carbonitrile derivatives. However, the cyanide ion present in the system induces the polymerization of electrophilic alkenes, such as acrylonitrile or methyl acrylate. 

Nitrogen-containing compounds are obtained from petroleum and natural gas primarily by three processes—i.e., nitration direct amination, and direct cyanidation of hydrocarbons. The author has listed review articles containing numerous references and the subject headings for searching indexes, in order to give the individual insight into the approach necessary in this field. 

The results of enzymatic determinations of ceruloplasmin are often expressed in arbitrary units, and the values judged in the light of a series of results obtained in normal subjects by the same method. Expression of the enzyme activity in milligrams of ceruloplasmin per unit volume of serum is also possible. The relation between oxidase activity and the amount of ceruloplasmin in serum can be determined by measuring in parallel samples of sera both the oxidase activity and the change of optical density at 610 mix before and after the addition of ascorbic acid or cyanide. On the basis of the known absorbancy index, the ceruloplasmin concentration can be calculated (see Section 2.2.1) and the relation between it and the enzyme activity determined. Alternatively, purified human ceruloplasmin can be used for standardization of the enzymatic method. The ceruloplasmin content of the purified preparation can be determined colorimetrically or, in the case of a highly purified preparation, by nitrogen analysis. Predetermined increments of ceruloplasmin can then be added to aliquots of a selected serum. It is convenient to select a serum with relatively low ceruloplasmin level to start with. Serum of a patient with Wilson s disease, some of whom have no measurable amount of enzyme activity, would be ideal for the purpose however, Walshe (W5) has recently found an inhibitor in these sera. 

Whereas within the family of the cubic Prussian blue analogs a large number of lattice constants have been determined, little attention has been devoted so far to polymeric cyanides not belonging to the cubic system. It must be emphasized, however, that polynuclear cyanides having unit cell symmetries other than cubic are by no means rare exceptions. Hexacyanometalates(III) of Zn2+ and Cd2+ are obtained not only in a cubic modification but also as samples with complicated and not yet resolved X-ray patterns of definitely lower symmetry than cubic (55). The exact conditions for obtaining either modification are not yet known in detail. The hexacyanoferrates(II), -ruthenates(II), and -osmates(II) of Mn2+ and several modifications of the corresponding Co 2+ salts show very complicated X-ray powder patterns which cannot be indexed in the cubic system (55). Preliminary spectroscopic studies show the presence of nearly octahedral M C6-units in these compounds, too. 

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