Calcium-containing cathodic material for solid oxide fuel cells

Using the citrate sol-gel method, a new complex oxide Ca_0.75Y_0.25Co_0.15Mn_0.85O_2.92 is synthesized. It is shown that this compound is crystallized in the rhombically distorted version of perovskite structure (a = 0.53397(8), b = 0.7470(1), c = 0.52810(6) nm). The phase is characterized by a low coefficient of thermal expansion (CTE) (13.8 ppm K^?1) and high electric conductivity (135 S/cm at 900°C). The chemical reaction between Ca_0.75Y_0.25Co_0.15Mn_0.85O_2.92 and the YSZ and GDC electrolyte materials is studied. The material is highly reactive and reacts with YSZ and GDC at 900°C and 1070°C, respectively. It is concluded that Ca_0.75Y_0.25Co_0.15Mn_0.85O_2.92 is a promising cathodic material for solid oxide fuel cells, provided a reliable protection SDC sublayer is formed between the cathode and the YSZ membrane.     

Electrochemical cells with multilayer functional electrodes

Microstructural and chemical changes in a NiO-YSZ electrocatalytic electrode were studied. The microstructural changes in the NiO-YSZ electrocatalytic electrode after the cell operation was compared with the electrode quenched under the applied voltage to suppress the oxidation process. The reversible reduction of NiO into Ni and the formation of intergranular Ni layers at the NiO/YSZ interface were investigated. It was shown that in a compositional range of the NiO-YSZ electrodes from 1/3 to 2/3 the value of the ambipolar conductivity increased with increasing voltage applied to the electrochemical cell. The observed reversible increase in the value of ambipolar conductivity of the electrocatalytic electrode is described in frames of the model of reversible reduction of NiO into Ni under the conditions of cell operation.     

Nonracemic Dimethylphenyl Glycerol Ethers in the Synthesis of Physiologically Active Aminopropanols

Russian Journal of Organic Chemistry - Six regioisomeric nonracemic dimethylphenyl glycerol ethers were synthesized by asymmetric dihydroxylation of the corresponding allyl dimethylphenyl ethers....     

Effective synthesis of non-racemic prenalterol based on spontaneous resolution of 3-(4-hydroxyphenoxy)propane-1,2-diol

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Effect of the thickness of the gas-sensitive layer on the response of solid state electrochemical CO2 sensors

This paper reports the effect of the sensitive layer thickness on the response of Nasicon based electrochemical CO₂ sensors. It was found that: (a) the cell voltage dependence on the thickness of the thin film Na₂CO₃ auxiliary electrode is well described within the theory of Schottky barriers formation in ionic crystals; and (b) sensors with relatively thick gas-sensitive layer are more reliable in dry CO₂ atmosphere.     

Multilayered electrochemical cell for NOx decomposition at moderate temperatures

A new multilayered electrochemical cell for NO_x decomposition was prepared. The cell demonstrated good characteristics at moderate temperatures (350–450 °C) and possessed much higher selectivity with respect to NO_x decomposition than previous one. It was found that the “crossover” process from high selective regime to the normal regime depends on the chemical composition of the catalytic electrode.     

Parameters of the conformational equilibrium in phenyl formate

Conclusions The shift of the position of the conformational equilibria in series of formic acid derivatives is determined primarily by steric factors.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1552–1555, July, 1988.