Magnetite in organisms

Synthesis of microcrystalline hematite and magnetite in organic solvents and effect of a small amount of water in the solvents. 

Magnetite in organisms 842 Maize, genome 12 Major groove of DNA 201, 213 Malaria 19... 

Tannins may be found bound up with magnetite in waterside tube deposits. Degradation products of amines, glycols, polymeric dispersants, chelants, and other organics may also be found and usually are reported in the deposit analysis as a loss on ignition. 

Fig. 17.6 Left hand side Model for the formation of magnetite in a Magnetospirillum species. L stands for an organic ligand. The oval forms represent specific Fe transport proteins, Right hand side Three magnetosomes encapsulated by a membrane (slightly modified) (Courtesy D. Schuler MPI Bremen see Schuler, 1999 A/ith permission).

Baumgartner, E. (1985) Dissolution of colloidal magnetite by organic acids in the presence of polyelectrolytes. Colloids Surfaces Conf., June 1985... 

Ghiorse.W.E. (2002) Effed of oxide formation mechanisms on lead adsorption by biogenic manganese hydroxides and their mixtures. Environ. Sci. Techn. 36 421-425 Nembrini, G. Buffle, J. Haerdi, W. (1976) Vol-tametric behavior of iron(III) hydrolyzed solutions and characterization of the reducible species. J. Colloid Interface Sci. 57 327-336 Nesson, M.H. Lowenstam, H.A. (1985) Biomineralization proceses of radula teeth of chitons. In Kirschvink, J.L. Stone, D.S. (eds.) Magnetite biomineralization and magneto reception in organisms. Plenum Press, New York, 333-363... 

As summarized in Table 14.1, teeth, bones, shells, etc. are indispensable components, consisting of inorganic mineral crystals and protein film, with sizes, morphologies, and textures suitable to fulfil the function of the particular organs involved. In this section we will look at hydroxyapatite, aragonite and calcite (two polymorphs of CaCO ), and magnetite in greater detail. 

Mann S. (1985) Structure, morphology, and crystal growth of bacterial magnetite. In Magnetite Biomineralization and Magnetoreception in Organisms (eds. J. L. Kirschvink, D. S. Jones, and B. J. MacEadden). Plenum, New York, pp. 311-332. 

Whenever acids are actually used to remove iron oxide from steel or iron, organic corrosion inhibitors are frequently used. While accelerative and inhibitive effects on the dissolution kinetics of the oxide have been observed, - few authors have tried to rationalize the results. Cumper et al. looked at the effect of heterocyclic nitrogen compounds (indole and pyrrole) on the dissolution rate of magnetite in 2N HCI. When... 

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