A positive electrode active material for a battery, the positive electrode active material comprising a compound having a crystal structure of space group Fm-3m and represented by composition formula (1): Li.sub.xMe1.sub.Me2.sub.O.sub.2 . . . (1). In the formula, Me1 represents one or more elements selected from the group consisting of Mn, Ni, Co, Fe, Al, Sn, Cu, Nb, Mo, Bi, Ti, V, Cr, Y, Zr, Zn, Na, K, Ca, Mg, Pt, Au, Ag, Ru, Ta, W, La, Ce, Pr, Sm, Eu, Dy, and Er, Me2 represents one or more elements selected from the group consisting of B, Si, and P, and the following conditions are met: 0<; 0<; +=y; 0.5x/y3.0; and 1.5x+y2.3.

Provided is a method for producing a near infrared-reflective black pigment containing at least the element calcium, the element titanium, and the element manganese, wherein the method produces a pigment that exhibits little of the elution of the element calcium and the element manganese that is caused by contact with acid. At least a calcium compound, a titanium compound, and a manganese compound are mixed by a wet grinding method and are calcined to provide a BET specific surface area of at least 1.0 m.sup.2/g and less than 3.0 m.sup.2/g. In another method, the element bismuth and/or the element aluminum is incorporated in a near infrared-reflective black pigment containing at least the element calcium, the element titanium, and the element manganese.

An organic matter decomposition catalyst that contains a perovskite type complex oxide represented by A.sub.xB.sub.yM.sub.zO.sub.w, wherein A contains 90 at % or more of at least one element selected from the group consisting of Ba and Sr, B contains 80 at % or more of Zr, M is at least one element selected from the group consisting of Mn, Co, Ni, and Fe, y+z=1, x>1, z<0.4, and w is a positive value that satisfies electrical neutrality.

Thermochemical storage materials having the general formula A.sub.xA.sub.1-xB.sub.yB.sub.1-yO.sub.3-, where A=La, Sr, K, Ca, Ba, Y and B=Mn, Fe, Co, Ti, Ni, Cu, Zr, Al, Y, Cr, V, Nb, Mo, are disclosed. These materials have improved thermal storage energy density and reaction kinetics compared to previous materials. Concentrating solar power thermochemical systems and methods capable of storing heat energy by using these thermochemical storage materials are also disclosed.

A composite thermistor material, a preparation method and an application thereof. The perovskite structure oxide and the pyrochlorite structure oxide are composite by solid state reaction method, which comprise process of ball milling, drying, and calcining. Then the thermistor ceramics with high temperature resistance and controllable B value are sintered at high temperature after mould forming, then the thermistor disks are coated by platinum paste, and then the platinum wire is welded as the lead wire to form thermistor element. The thermistor of the invention can realize temperature measurement from room temperature to 1000 C. and has good negative temperature coefficient thermistor characteristics. The thermistor coefficient B can be adjusted by changing the two-phase ratio to meet the requirements of different systems.

The invention concerns a method for converting a feedstock selected from sugars or sugar alcohols, alone or in a mixture, into mono- or polyoxygenated compounds, wherein the feedstock is contacted with at least one heterogeneous catalyst comprising a support selected from perovskites of formula ABO.sub.3, in which A is selected from the elements Mg, Ca, Sr and Ba and B is selected from the elements Fe, Mn, Ti and Zr, and the oxides of elements selected from lanthanum, neodymium, yttrium and cerium, alone or in a mixture, which oxides can be doped with at least one element selected from alkali metals, alkaline earths and rare earths, in a reducing atmosphere, at a temperature of 100 C. to 300 C. and at a pressure of 0.1 MPa to 50 MPa.

A composite positive active material including a composite represented by Formula 1:
Li.sub.2MO.sub.3.(1)[xLi.sub.2MnO.sub.3.(1x)Li.sub.dNi.sub.aCO.sub.bM.sub.cO.sub.2]Formula 1 wherein, in Formula 1, M is titanium (Ti) or zirconium (Zr); M is manganese (Mn), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al), boron (B), or a combination thereof; and 0<<0.5; 0x<0.3; a+b+c1; 0<a<1; 0<b<1; 0<c<1, and 0.95d1.05.

There is provided a thermoelectric conversion material which is characterized by being composed of a sintered body of plate-like crystals of a composite oxide represented by general formula (2) Bi.sub.fCa.sub.gM.sup.3.sub.hCo.sub.iM.sup.4.sub.jO.sub.k, and by having a density of 4.0-5.1 g/cm.sup.3. This thermoelectric conversion material is also characterized in that: when observed by SEM, the ratio of the plate-like crystals of a composite oxide represented by general formula (2) having an inclination in the major axis direction within 020 relative to the surface of the thermoelectric conversion material is 60% or more on the number basis; the average length of the lengths of the plate-like crystals of a composite oxide represented by general formula (2) is 20 m or more; and the aspect ratio of the plate-like crystals of a composite oxide represented by general formula (2) is 20 or more.

Provided is a black fine particulate near-infrared reflective material which is a perovskite-type complex oxide containing at least an alkaline earth metal element, titanium element, and manganese element, having a BET specific surface area within a range of 3.0-150 m.sup.2/g. The Hunter L value, as an indicator of blackness, is 30 or less, and the reflectivity at a wavelength of 1200 nm, as an indicator of near-infrared reflective power, is 40% or above.

A solar power system and materials capable of storing heat energy by thermochemical energy storage are disclosed. Thermal energy is stored as chemical potential in these materials through a reversible reduction-oxidation reaction. Thermal energy from concentrated sunlight drives a highly endothermic reduction reaction that liberates lattice oxygen from the oxide to form O.sub.2 gas, leaving energy-rich, oxygen-depleted particles. When desired, the heat is recovered as the particles are re-oxidized in an exothermic reaction upon exposure to air. The system may be integrated with a power generation system to generate power.