Formation of Calcium Superoxide

Abstract

by Dent•. 500 µl. of deproteinized and desalted plasma, and amonnts of desalted urine corresponding to 250 µgm. of total nitrogen (Kjeldahl), were spotted on to 60-cm. squares of Whatman No. 4 paper,

Ab InitioQuantum Mechanical Study of the Structure and Stability of the Alkaline Earth Metal Oxides and Peroxides

“…2, indicating that the crystal structure of the compound is uncertain. We note, moreover, that the earlier structures proposed by Kotov et al (7) and Brosset et al (8) have not been confirmed. In addition, calcium peroxide has never been prepared in a pure form: all samples contain water and/or hydrogen peroxide, since the synthetic preparations use water as a solvent and hydrogen peroxide as one of the starting materials (7).…”

“…The calcium carbide structure has also been proposed for CaO (7,8). The structural investigations are based on powder diffraction data of poorly crystalline samples and show additional weak reflections which cannot be attributed to the calcium carbide structure (5,7), as shown in Fig.…”

Problems of Mediterranean–saharan Migration

“…) and one Aquatic Warbler was among the corpses found by Cott on an outlier of the eastern Canary Islands (Bannerman 1931). Brosset (1956) recorded Aquatic Warblers as common in marshes in northeastern Morocco for a few days in both autumn and early spring. The sole Egyptian record is on sight, by Meiklejohn (1944) at Ismailia, on the Canal.…”

Phase diagrams for the YBa2Cu3O7 family — ANNO 1996

“…The slope then refers to the number of defects formed in the originally stoichiometric solid by an accommodation of 2 oxygen atoms (from the 02 molecule) subjected to the electroneutrality condition. The problem is, however, that the simple ionic defect reaction of this type: 02 + Vi + 2Cu~u ~ Oi" + 2Cucu (16) gives a slope of 6 instead of 3. Such a serious disagreement is usually attempted solved by abandoning the assumption of the ionicity from the defect model and/or considering defect clusters instead.…”

“…This should be taken into consideration in the evaluation of the oxygen dissociation pressure, which will vary with the content of peroxide in the solid-solution phase [13]. To illustrate rough trends, equilibrium oxygen pressures for SrO1.97 [12], and for the oxide-saturated barium peroxide are expressed (p in Pa, Tin K) [12,13] The peroxides crystallize [14,15] with the CaC2-type structures: CaO2 {P4/mmm; 356, 596} [16], SrOz {355,655} [17] and BaO2 {381.14(6), 682.15(11)} [15].…”