Natural perovskite: (CaII 0.95 (1)CeIII 0.011 (2)NaI 0.010 (4))(FeIII 0.022 (2)TiIV 0.98 (1))O3
نویسندگان
چکیده
A natural sample of perovskite (calcium caesium sodium iron titanium oxide) from the Tapira Alkaline Complex in southeastern Brazil was found by electron microprobe analysis to have the chemical formula (Ca(2+) (0.95 (1))Ce(3+) (0.011 (2))Na(+) (0.010 (4)))(Fe(3+) (0.022 (2))Ti(4+) (0.98 (1)))O(2-) (3) and by IR spectroscopy to be an anhydrous mineral. Oxygen anions are arranged around Ti(4+) in an almost perfect octa-hedron and around Ca(2+) in a distorted 12-fold polyhedron.
منابع مشابه
Time-Varying Systemic Risk: Evidence from a Dynamic Copula Model of CDS Spreads
!1 -0.030 0.004 0.017 -0.022 -0.005 -0.052 0.047 !2 -0.029 0.004 0.018 -0.022 -0.005 -0.048 0.043 !3 -0.029 0.004 0.016 -0.021 -0.005 -0.043 0.038 !4 -0.028 0.003 0.017 -0.023 -0.005 -0.047 0.042 !5 -0.028 0.004 0.016 -0.020 -0.005 -0.046 0.041 !6 -0.027 0.004 0.016 -0.020 -0.003 -0.044 0.040 !7 -0.026 0.003 0.016 -0.022 -0.004 -0.042 0.038 !8 -0.026 0.003 0.016 -0.020 -0.005 -0.043 0.038 !9 -0...
متن کاملConversion of iodide to hypoiodous acid and iodine in aqueous microdroplets exposed to ozone.
Halides are incorporated into aerosol sea spray, where they start the catalytic destruction of ozone (O3) over the oceans and affect the global troposphere. Two intriguing environmental problems undergoing continuous research are (1) to understand how reactive gas phase molecular halogens are directly produced from inorganic halides exposed to O3 and (2) to constrain the environmental factors t...
متن کاملSomatic D816V KIT mutation in a case of adult-onset familial mastocytosis.
Rank # Genes Highest OR (L95-U95) Smallest P-value # Genes Highest OR (L95-U95) Smallest P-value # Genes Highest OR (L95-U95) Smallest P-value 1 IRAK1 0.70 (0.55-0.90) 0.006 IRAK1 0.73 (0.54-0.99) 0.042 IRAK1 0.50 (0.28-0.86) 0.013 2 MKK3 1.28 (1.10-1.50) 0.002 IRAKM 0.53 (0.31-0.90) 0.019 SIGIRR 0.54 (0.35-0.85) 0.008 3 ERK2 1.22 (1.05-1.42) 0.010 RIP1 1.49 (1.04-2.12) 0.012 TRAF6 0.65 (0.46-0...
متن کاملFormation and Structural Characterization of 1:1 Ordered
The phase stabilities in the (1 − x)Ba(Zn1/3Ta2/3)O3 (BZT)– xBaZrO3 (BZ) system have been investigated using samples prepared by the mixed-oxide method. The substitution of Zr4+ destabilizes the 1:2 cation ordering in BZT and promotes the formation of a cubic, 1:1 ordered structure with a doubled perovskite repeat. The homogeneity range of the 1:1 phase extends from x = 0.04 to approximately x ...
متن کاملInfluence of Cation Order on the Dielectric Properties of Pb(Mg1/3Nb2/3)O3-Pb(Sc1/2Nb1/2)O3 (PMN-PSN) Relaxor Ferroelectrics
The effect of the B-site cation chemistry and ordering on the dielectric properties of solid solutions in the (1-x)Pb(Mg1/3Nb2/3)O3-Pb(Sc1/2Nb1/2)O3 (PMN-PSN) perovskite system was examined in samples with 0.1 ≤ x ≤ 0.9. Thermal annealing treatments were effective in inducing long-range B-site order in the samples within this compositional range. The well-ordered, large chemical domain ceramics...
متن کامل