Olivines

Olive oil [8001-25-0] Olive oil solubility Olives Olive tree Olivine... 

Fig. 1. A "barred olivine" chondrule from the Allende-type CV chondrite that feU in Mexico in 1979. The transmitted polarized light image of the 0.5 mm-diameter chondrule was taken from a poHshed thin section. The bars are composed of oHvine, (Mg,Fe)2Si04. The interstitial material is glass quenched...

Figure 4.28. Measured and calculated shock temperatures versus pressure for for-sterite for low-pressure (olivine), mixed phase, and high-pressure phase regime (possibly MgO periclase) -I- MgSi03 (perovskite)). Shock temperatures in the mixed phase regime (Ahrens et al., 1969).

Figure 4 Spectrum of diffusion in the mineral olivine ((Mg, Fe)2 SiO ) taken using nonresonant profiling technique with the reaction (p, a) Both the a particles resulting from the nuclear reaction and backscattered protons are collected. Inset shows expanded region of the spectrum, where a yield indicates diffusion of into the material.

Cblorotriruethylsilane-accelerated divinylcuprate addibon to enal 61, followed by a Wibig oleflnation, provided enoate 62 as a single stereoisomer in excellent yield (Sdieme 6.10) [23]. Hie enoate 62 cnUld be transformed in ftillher steps into olivin i63), die aglygon of olivomycin. 

Magnesium. Mg, at wt 24.312, at no 12, valence 2. Isotopes 24 (77.4%), 25 (11.5%) 26 (11.1%). Physical properties of 99.9% pure Mg are (riven in the fnllnwino tsKle fRef 10 n 6791 Mg is very abundant in nature, occurring in substantial amounts in many rock-forming minerals such as dolomite, magnesite, olivine, and serpentine. In addition, it is also found in sea water, subterranean brines, and salt beds. 

A similar synthetic strategy was applied in the synthesis of menogaril 83, another important anthracycline antitumour antibiotic, and to the synthesis of the tricyclic core of olivin 87, the aglycon of the antitumour antibiotic olivomycin [61,62]. In both cases a tandem benzannulation/Friedel-Crafts cyclisation sequence yielded the tetracyclic and tricyclic carbon core, respectively (Scheme 42). 

Scheme 42 Studies towards the synthesis of menogaril and olivin...

The effect of small valence and large coordination number is further shown by the observation that silicon tetrahedra, which share comers only with aluminum octahedra, share edges with magnesium octahedra (in olivine, chondrodite, humite, clinohumite) and with zirconium polyhedra with coordination number eight (in zircon). 

Silicates also lead to uptake of CO2. Weathering of a non-aluminum silicate like Mg-olivine may be written... 

Many of the minerals that form the Earth s crust contain oxoanions. Examples of carbonates are CaC03 (limestone) and MgCa (003)3 (dolomite). Barite (BaS04) is a sulfate mineral. An important phosphate is Caj (P04)3 F (apatite). Two silicates are zircon (ZrSi04) and olivine (a mixture of MgSi04 and FeSi04). 

Different minerals contain different metal cations to balance the -4 charge on the orthosilicate ion. Examples Include calcium silicate (Ca2 Si04), an important ingredient in cement, and zircon (ZrSi04), which is often sold as artificial diamond. One of the most prevalent minerals in the Earth s mantle is olivine, Af2(Si04), in which M is one or two of the abundant metal cations, Fe -, Mg -, and Mn +. 

The collection of spectra obtained at Spirit s landing site reveals various miner-alogical signs of weathering. Spectra obtained on the basaltic rocks and soil on the plains show mainly olivine and pyroxene and small amounts of nonstoichio-metric magnetite, and only comparably small amounts of weathering. An example... 

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