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The compressive LaMnO3+δ thin films with thickness of ∼20 nm are grown on LaAlO3 (001) single crystal substrates under various oxygen environment. With decreasing oxygen pressure, the in-plane compressive strain is enhanced. It is found that the breathing mode (Q1) and the basal plane distortion mode (Q2) of MnO6 octahedron are suppressed, while the octahedral stretching mode (Q3) is promoted. The promoted Q3 switches the orbital order from x2-1/y2-1 to (x2-y2)+(z2-1) type. The ferromagnetic (FM) transition temperature Tc increases from 85 K to 105 K and the low-temperature magnetization increases greatly by 175%. The abnormal enhancement of magnetization with decreasing oxygen pressure is ascribed to the strain enlarged FM domains due to the decreased MnO6 distortion and the switched orbital ordering. This result is advantageous to explain the novel phenomena in LaMnO3-related systems.

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With the energy consumption increasing, the coal supply in China has been becoming tight, which has made it difficult for thermal power generation in Yunnan Province. Making full use of local inferior coal and biomass resources in Yunnan can remedy the lack of fuel in power plants. In this paper, an oxygen-rich atmosphere thermogravimetric experiment was performed for a blended sample of Xiaolongtan lignite, Yiliang tobacco rod, and Fuyuan bituminous coal. The combustion characteristics of the mixed fuel under several key operating parameters (i.e., mass ratios, oxygen concentration, and heating rates) were studied. The response surface methodology was used to determine the optimal blending ratio of the three fuels. The results show that the ignition and burnout temperature of coal decrease and the combustion time diminishes with the enrichment of oxygen. The optimal oxygen concentration in the practical application is around 30%. The activation energy and preexponential factor increase with the enlargement of oxygen concentration. Such complex evaluation and optimization approach ensure the stable operation of thermal power plant production.

A series of polycrystalline YMn1−xRuxO3 (0 ≤ x ≤ 0.2) samples were prepared by traditional solid-state reaction method. Effects of doping on the microstructures and magnetic properties were investigated. Microstructural results reveal that samples crystallize in a single hexagonal structure with P63cm group for x ≤ 0.1. Lattice parameters a, c, and unit-cell volume of YMn1−xRuxO3 are found to increase with doping content, which are ascribed to the larger radius of Ru3+ than that of Mn3+. Weak ferromagnetism is found and is enhanced with increasing doping concentration x. The bond angles of Mn-O3-Mn and Mn-O4-Mn are changed in the opposite trends, which break the Mn-Mn exchange interaction, thus the antiferromagnetic ordering. The MnO5 bipyramid is found to be relieved and the trimerization of Mn ions is weakened. These structural modifications result in the increase of weak ferromagnetism ordering in samples.