Iron salts observational studies

In those days, we were interested in coating metals like bare iron, steel, stainless steel or other metals non-electrochemically by using polyaniline dispersions or polyaniline containing lacquers. The first experiments had shown that some improvement in corrosion protection could be obtained [109], Further progress in lacquer formulation had been the basis for quite successful long-term salt spray studies [110], but the effects observed in this practical test have not been convincing for corrosion protection experts. 

Studies on the rate of reduction of ceruloplasmin have involved some substances which according to McDermott et al. 163) require iron salts to act as substrates, and it appears that iron may also play a role in the transient approach, to the steady state as well as the overall rate under conditions of both O2 and substrate saturation. Osaki 169) has observed that iron chelating agents such as 1,10 phenanthroline and apotransferrin quite dramatically impede the reduction of Type 1 Cu2+ by ascorbate. For example, a 16.5 mM, Chelex treated, ceruloplasmin solution was half-reduced in a 3 sec time period in the absence of apotransferrin and 7 sec in the presence of 20 fM. apotransferrin, while... 

The authors additionally proposed an alternative explanation for the observed increase in conversion and selectivity that involves the reduction of Ru(III) byproducts. For instance, the added tin and iron salts have well-described redox couples (Sn(II)/Sn(IV) and Fe(ll)/Fe(lll)) that could be acting as single-electron reductants to convert the Ru(lll) decomposition products of catalyst 1 back to the necessary Ru(II) oxidation state. Some evidence for this theory is that the addition of FeClg, which cannot act as a reductant, did not improve any of the metathesis reactions studied. 

Catalyst studies have promoted attention with description of the use of iron salts to prevent ether formation during ester exchange polymerization. Model compounds have been employed to elucidate the meehanisms of metal ion catalysis in both transesterification and polycondensation reactions. A differential microcalorimeter has been used to assess the relative reactivities of catalyst systems for the poly-transesterification of bis-(2-hydroxyethyl tere-phthalate) and the relationship between the viscosity of the polymerizate and the temperature of the maximum rate of heat production has been investigated. Studies on antimony(v) compounds have indicated that their activity increases during the course of 2GT synthesis. This observation has been ascribed to the reduction of the antimony(v) compounds by acetaldehyde produced by 2GT decomposition. 

Iron complex-catalyzed isomerization of allylic alcohols was found during the studies on the hydrolysis of 7t-allyliron tricarbonyl salts. The isomerization of allyl alcohol to propionaldehyde was observed on heating in the presence of Fe(CO)s (Equation (9)).30... 

Inflammable air from the solution of metals in acids had been observed and commented on for at least a hundred years, but only after the attention of chemists had been directed toward gases generally did a systematic study appear. Cavendish obtained the inflammable air by dissolving zinc, iron, and tin in dilute vitriolic acid or in spirit of salt. The same metals also dissolved readily in nitrous (nitric) acid, and in concentrated vitriolic (sulfuric) acid with heat, but the resulting airs were not at all inflammable. He interpreted these reactions as follows ... 

A comparative study of the products of dehydration of the dihydrogen monophosphates of polyvalent cations showed that the stable end-products for cations with ionic radii between 0.57 and 1.03 A. (Cu++, Mg++, Ni++, Co++, Fe++, Mn++, Zn"1-1", Cd++, A1+++) are tetrametaphosphates. When the cations are either larger or smaller the end-products of dehydration are crystalline high-molecular polyphosphates (Li+, Be++, K+, Rb+, Cs+, Ag+, Zn++, Cd++, Hg++, Ca++, Sr++, Ba++ Pb++, Cr+++, Fe+++, Bi+++). In the case of the alkali salts only sodium trimetaphosphate occurs as a condensed phosphate with a cyclic anion (304, 305). Up to the present, an alkali tctrametaphosphate has not been observed as the dehydration product of a dihydrogen monophosphate. Consequently, alkali tetrametaphosphates arc obtainable only indirectly. Reference is made later (Section IV,C,4) to the fact that the tetraphosphates of barium, lead, and bismuth are formed as crystalline phases from melts of the corresponding composition. There are also reports of various forms of several condensed phosphates of tervalent iron and aluminum (31, 242, 369). 

W. Plotnikoff found the mol. conductivity of ethereal soln. diminishes with dilution, and increases with rise of temp. W. Hittorf attempted to determine the transport number of the anion in aq. soln. of normal sodium phosphate, but the salt was so much hydrolyzed that most of the current was carried by the alkali. With aq. soln. of sodium hydrophosphate, the transport number of the HP0"4-anion was 0-516 and with sodium dihydrophosphate for the H2PO 4-anion, 0-383. J. F. Daniell and W. A. Miller also made some observations with this salt. W. Hittorf found with soln. of potassium dihydrophosphate, the transport number of the H2P0,4-amon was 0-277. O. Wosnessensky measured the potential difference at the boundary of phosphoric acid and a non-aqueous solvent. P. Pascal studied the magnetic properties. J. Murray tried if he could decompose a soln. of the acid by magnetized iron. 

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