Co-olivine

Zn-Co olivine, and KAlSi3O0 (sanidine) - NaAlSi308 (high albite). (cf. Carlson and Colbiurn, 19 2, and Green, 1970a, b). 

Despite quite some progress reported in improving the performance and lifetime of anode materials, a great deal of research needs to be dedicated to the improvement of the cathode in Li-ion batteries. This task was addressed by hydrothermal carbon coating techniques. Thus, Olivine LiMP04 (Me = Mn, Fe, and Co) cathodes with a thin carbon coating have been prepared by a rapid, one-pot, microwave-assisted hy-... 

The first extensive study of iron-silicate minerals published was by deCoster and co-workers (7, 24). Their results are summarized in Table VI. Augite is a pyroxene containing considerable Na and Ca. No iron percentage was given for the olivine studies. The other minerals are included for comparison. The values given here for biotite are averages for their three untreated samples, which have two sites described as distorted octahedra. Heat treatment at 700°C. for one hour resulted in the emergence of a new Fe peak in biotite. 

Recently, LiFeP04, which adopts the olivine structure, has been widely studied as a possible cheap cathode material.Although the specific capacities of this material and the related NASICON structures are relatively low (typically 100 mAhg ), these compounds are cheap and open up new avenues for research. Li MAS NMR studies of a series of olivines LiMP04 with M = Mn, Fe, Ni, and Co were carried out by Tucker et A single resonance with large... 

Figure 5JO Experimentally observed intracrystalline disorder in (Mg,Fe)2Si04 mixture, compared with theoretical distribution curves generated by interionic potential calculations. = Aikawa et al. (1985) = Smyth and Hazen (1973) = Brown and Prewitt (1973) 0,0, A = Ottonello et al. (1990). From G. Ottonello, F. Princivalle, and A. Della Giusta, Temperature, composition and/o effects on intersite distribution of Mg and Fe in olivines. Physics and Chemistry of Minerals, 17, 301-12, copyright 1990 by Springer Verlag. Reprinted with the permission of Springer-Verlag GmbH Co. KG.

Bostrom D. (1988). Experimental studies of (Ni,Mg)—and (Co,Mg)—olivine solid solutions by single crystal X-ray diffraction and solid state emf method. Ph.D. thesis. Department of Inorganic Chemistry, University of Umea, Umea, Sweden. 

Ghose S. and Wan C. (1974). Strong site preference of Co " in olivine Coi ioMgo.9oSi04. Contrib. Mineral Petrol, 47 131-140. 

The crystal radius thus has local validity in reference to a given crystal structure. This fact gives rise to a certain amount of confusion in current nomenclature, and what it is commonly referred to as crystal radius in the various tabulations is in fact a mean value, independent of the type of structure (see section 1.11.1). The crystal radius in the sense of Tosi (1964) is commonly defined as effective distribution radius (EDR). The example given in figure 1.7B shows radial electron density distribution curves for Mg, Ni, Co, Fe, and Mn on the M1 site in olivine (orthorhombic orthosilicate) and the corresponding EDR radii located by Fujino et al. (1981) on the electron density minima. 

Given that olivine-compatible elements such as Mg or Co are likely to be most concentrated in the first olivine crystals to form an olivine cumulate, assays through two cumulate peridotite units of the BLUC reveal trends that are consistent with a downward younging direction (Fig. 5). 

The aqueous fluids formed by melting of ices in asteroids reacted with minerals to produce a host of secondary phases. Laboratory studies provide information on the identities of these phases. They include hydrated minerals such as serpentines and clays, as well as a variety of carbonates, sulfates, oxides, sulfides, halides, and oxy-hydroxides, some of which are pictured in Figure 12.15. The alteration minerals in carbonaceous chondrites have been discussed extensively in the literature (Zolensky and McSween, 1988 Buseck and Hua, 1993 Brearley, 2004) and were most recently reviewed by Brearley (2006). In the case of Cl chondrites, the alteration is pervasive and almost no unaltered minerals remain. CM chondrites contain mixtures of heavily altered and partially altered materials. In CR2 and CV3oxb chondrites, matrix minerals have been moderately altered and chondrules show some effects of aqueous alteration. For other chondrite groups such as CO and LL3.0-3.1, the alteration is subtle and secondary minerals are uncommon. In some CV chondrites, a later thermal metamorphic overprint has dehydrated serpentine to form olivine. 

Fractional crystallisation has been dominated by separation of various proportions of clinopyroxene and olivine in the mafic magmas, and of cli-nopyroxene and feldspars in the felsic melts. These generated decrease in ferromagnesian elements (FeO, MgO, Ni, Co, Cr, etc.) and increase in incompatible elements (e.g. Th, Ta, Nb, REE), with ongoing evolution. In contrast, ratios of incompatible trace elements were not affected by fractionation processes, and can be used to infer compositions of mantle-equilibrated melts. 

Shibata, T., Takahashi, E., Ozima, M. (1994) Noble gas partition between basaltic melt and olivine crystals at high pressure. In Noble Gas Geochemistry and Cosmochemistry, J. Matsuda, Ed., pp. 343-54. Tokyo Terra Scientific Publishing Co. 

Reversible electrochemical lithium deintercalation from 2D and 3D materials is important for applications in lithium-ion batteries. New developments have been realized in two classes of materials that show exceptionally promising properties as cathode materials. The first includes mixed layered oxides exemplified by LijMn Nij, Co ]02, where the Mn remains inert to oxidation/reduction and acts as a framework stabilizer while the other elements carry the redox load. Another class that shows much potential is metal phosphates, which includes olivine-type LiFeP04, and the NASICON-related frameworks Li3M2(P04)3. 

Fig. 1. If equilibrium is maintained on cooling, CO will be converted largely to CH4 (solid lines) before metastable formation of more complex hydrocarbons by the Fischer-Tropsch reaction becomes possible (dashed lines). However, the reaction is very slow in the absence of catalysts, and may not have begun until about 400 K, when catalysts such as serpentine and magnetite became available through the hydration of olivine. Thus CO may have persisted metastably between 600 and 400 K...

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