Prussian Order

Fischer was awarded the Prussian Order of Merit and the Maximilian Order for Arts and Sciences. 

The ideal composition of Prussian blue is Fe(III)4[Fe(II)(CN)g]3.15H2O. The crystal structure is cubic. All Fe(III) lattice sites are occupied, whereas those of Fe(II) are only 75% occupied. At low temperatures the paramagnetic Fe(III) ions order ferromagnetically (T = 5.6 K). Finally we note that upon replacing Fe(II) by Ru(II) or Os(II) the color properties are not drastically influenced. 

Haber agreed to find a chemical weapon. He had already volunteered his services to the military the Prussian ideal was duty and unconditional service to the state. Few statesmen anywhere argued that humanitarian concerns were more important than national interests most Europeans believed that military orders must be obeyed even if they violated moral principles. Haber thought of himself as a latter-day Archimedes, the ancient Greek scientist who served mankind in peace and his fatherland in war. In service to his country, Haber invented a potentially fatal, offensive weapon—poison gas. 

The electrochemical rate constants for hydrogen peroxide reduction have been found to be dependent on the amount of Prussian blue deposited, confirming that H202 penetrates the films, and the inner layers of the polycrystal take part in the catalysis. For 4-6 nmol cm 2 of Prussian blue the electrochemical rate constant exceeds 0.01cm s-1 [12], which corresponds to the bi-molecular rate constant of kcat = 3 X 103 L mol 1s 1 [114], The rate constant of hydrogen peroxide reduction by ferrocyanide catalyzed by enzyme peroxidase was 2 X 104 L mol 1 s 1 [116]. Thus, the activity of the natural enzyme peroxidase is of a similar order of magnitude as the catalytic activity of our Prussian blue-based electrocatalyst. Due to the high catalytic activity and selectivity, which are comparable with biocatalysis, we were able to denote the specially deposited Prussian blue as an artificial peroxidase [114, 117]. 

The resulting Prussian blue-based nano-electrode arrays in FIA demonstrate a sub-ppb detection limit (1 X 10 9 mol I. ) and a linear calibration range starting from the detection limit and extending over seven orders of magnitude of H202 concentrations (1 X 10 9 1 X 10 2 mol L ), which is the most advantageous analytical performance in electroanalysis. As a conclusion from the evidence in this chapter, Prussian... 

Metal hexacyanoferrates-based biosensors were developed for analysis of glucose [11, 114, 118, 127, 147, 149, 152, 155-166], ethanol [11], D-alanine [147], oxalate [167-169], cholesterol [170, 171], glutamate [114, 119], sucrose [172], and choline [163], Among the transducers used Prussian blue undoubtedly dominates especially if one takes into account that instead of both chromium and cobalt hexacyanoferrates the activity of the transducers in publications [149, 159, 167, 168] was most probably provided by Prussian blue [117]. The sensitivity of cupric hexacyanoferrate is several orders of magnitude lower compared to Prussian blue. However, chemically synthesized... 

F. Herren, P. Fisher, A. Ludi, and W. Haig, Neutron difraction study of Prussian blue, Fe4[Fe(CN)6]3 xH20. Location of water molecules and long-range magnetic order. Inorgan. Chem. 19, 956-959 (1980). 

P,2, S transition, ratio r, 35 368 Prussian Blue, 46 41 -like phases, 43 245-249 magnetic ordering, 43 246-247 magnetic properties, 43 248 relation to Berlin green, 8 120-121 structure studies on, 8 119-120 Prussiates, M6ssbauer spectrum of, 6 464-466 Pseudoazurins, 36 382 x-ray crystal structures, 36 389-390 Pseudocatalase, 40 379... 

Not surprisingly, the very interesting and practically useful properties of Prussian blue have resulted in several studies of similar hexacyano derivatives [114] but only a few of them (e.g., ruthenium- and osmium-based systems) have found use in electrochromic devices. More systematic studies should, indeed, be called for in order to harvest the full potential of this group of compounds. 

Accdg to Mr. R. Baumann of PicArsn, these compds are not catalysts, but rather "modifiers , or additives . They are incorporated into solid proplnts in order to modify or affect their combustion characteristics The compds which affect burning rate include Prussian blues, Aram dichromate, trichromate or tetrachromate, etc). Some compds may be employed to reduce the variability of burning rate with combustion pressure and temperature (Eg Pb stearate or salicylate). Other compds may be used to reduce the tendency toward oscillatory combustion(Eg A1 powder in small quantity), or to affect flash characteristics of exhaust gases [Eg KaS04, Ba(N03)2,... 

Amm or K dichromates, Fe or Pb oxides, etc) 4)E.F. Morello, USP 2942962(1960) CA 54, 25830-31(1960XComposite AN rocket proplnts contg Prussian blue as combustion catalyst some DPhA which is incorporated in order to render the propint less susceptible to gassing... 

Such conclusions are, however, extremely speculative at present. The Fe(CN) 3"/ system suffers from a number of complications, including the possibility of surface reactions to form Prussian Blue-like cyano-bridged chains. Details of these results will be given in a forthcoming publication. (14) This brief summary is included here in order to illustrate how information on electron delocalization effects for adsorbed redox couples might be obtained, at least in principle, by examining potential-dependent SERS frequencies. 

In order to remove the catalytically active iron salts, a portion of the circulating electrolyte is periodically removed, after having passed through the cathode spaces to get rid of active oxygen. Iron is precipitated by potassium ferrocyanide and the Prussian blue deposit is filtered off by a suotion filter. The purified electrolyte is then returned to normal circulation. 

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