Advanced Materials Research Vols. 391-392

Abstract: A novel alkali-alkaline earth borate K₂O•CaO•4B₂O₃•12H₂O：Sm³⁺ has been synthesized by facile industrialization and pollution-free water solution method .The samples were characterized by chemical analysis, FT-IR spectra, X-ray powder diffraction and SEM, fluorescence spectrum. It is found the product owns rhombic group space, about 3mm long. Under 828 nm excitation, the fluorescence spectrum is indicated that the host material K₂O•CaO•4B₂O₃•12H₂O has properties of infrared-visible up-conversion，and it appears orange. Adding Sm ³⁺ makes emission spectrum stronger.

Abstract: Adsorption behavior disciplinarian of the immobilized tannins to metal ions was studied. Experiments showed that adsorption capacities of metal ions lied in ns grouse in the periodic table of elements were relatively low. For the metal ions lied in np grouse in the periodic table of elements, their adsorption capacity increased with the increasing in the radius of metal ions. Adsorption capacities of metal ions having low values in the first transition series in the periodic table of elements, such as Mn(II), Fe(II), Fe(III), Co(II) and Ni(II), were more lower than that of the metal ions having high values, such as Cr(VI), Mn(VII) and V(V). For the metal ions in the second, the third transition series and the actinide series, adsorption capacities were relatively higher than that of metal ions in lanthanide series.

Abstract: Lanthanum-doped anatase TiO₂ coatings, which were composed of assemble crystalline of 50 nm diameter particles have been successfully fabricated by sol–gel dip-coating process on light leakage quartz fiber (LQF) which length is 15cm and diameter is 125μm. This was achieved by adjustment of the lanthanum-doped sol–gel parameters such as molar ratio of precursors in lanthanum-doped TiO₂-sols, the ratio of titanium tetrabutoxide to polyvinyl alcohol, dip-coating velocity, drying duration in air, thermal treatment and number of cyclical time of the process. Titania nano crystals were prepared by ambient temperature in a liquid media using titanium tetrabutoxide as precursor, and the crystallization of amorphous precursor was preceded by peptizing with acid and then refluxing for a periodic time in homothermal water-bath. The photocatalytic properties of the lanthanum-doped TiO₂ films were testified by the photo degradation of methyl orange. The lanthanum-doped anatase TiO₂ thin films were characterized by XRD and TEM.

Abstract: In order to clarify the role of Dy³⁺ on persistent luminescence properties of MgSiO₃:Mn²⁺, Dy³⁺ and explain the persistent luminescent mechanism, the positron annihilation technique was used to study the defect states of MgSiO₃:Mn²⁺, Dy³⁺. It was revealed that the structure of deeper traps were not normally respected Mg²⁺ vacancies and oxygen vacancies but the associated defect V"Mg-2Dy•Mg which emerged by Dy³⁺ doping in MgSiO₃:Mn²⁺. This associated defect V"Mg-2Dy•Mg resulted in the excellent persistent luminescence in MgSiO₃:Mn²⁺, Dy³⁺ phosphor and a possible persistent luminescent mechanism for MgSiO₃:Mn²⁺, Dy³⁺ was given.

Abstract: By physical simulation experiments, the features of alkali-free binary flooding system (polymer and a new surfactant BS) were contrasted with weak base ternary flooding system and alkali ternary flooding system. The experiment results showed that interfacial tension of BS binary system is the lowest. In the absence of alkali, the viscosity and elasticity of binary system were higher than those of other two ternary flooding systems. By physical simulation experiments with artificial heterogeneous cores, the recovery of BS binary flooding system was 2 percent higher than that of weak base ternary flooding system, and 1.4 percent higher than that of alkali ternary flooding system.

Abstract: In laboratory, the minimum miscible pressure (MMP) of oil and CO₂ was studied by using a slim tube model. The results showed that the greater the gas injection pressure, the higher the cumulative recovery. The gas breakthrough when the gas was injected with a volume of 0.7~0.8PV, the trend of cumulative recovery increase slowed down and the produced gas-oil ratio increased dramatically. Core flooding experiments were carried to compare the effects of CO₂ and water flooding. As a result, the ultimate oil recovery of CO₂ flooding increased with the increase of gas injection pressure. If the gas flooding was miscible, the ultimate recovery of CO₂ flooding was generally higher than that of water flooding.

Abstract: Biochar, a by-product of biomass pyrolysis, has been suggested as a mean to combat climate change by sequestering carbon, and at the same time to provide energy and increase crop yields. As one possible source of the components with high aromatic structure in soil humus, biochar is of great importance in increasing soil carbon storage and improving soil fertility, and in maintaining the balance of soil ecosystem. This paper briefly reviewed and synthesized recent findings and discussions regarding the production and characteristics of biochar, its effects on global climate change and particularly in relation to the environmental effect of biochar in soil. Research prospects were briefly discussed on the environmental behavior and effect of biochar in soil ecosystem.

Abstract: This article discussed the development process and anion release mechanism of anion printing poplin. Through ultra-fine processing and special modification, 6-ring stone and a variety of functional materials were used to process anion additives. The particle size of anion additives is 50-900 nm. Mix the additive and other additives, then modulation into sizing agent. Through experiments and instruments test, the poplin which obtained by an ordinary printing process, is proved has higher wear behavior. At the same time, the poplin can stable and lasting release anion reached 3000/cm³, reach people's health requirements

Abstract: Li₃V₂(PO₄)₃/C composite material has been prepared by sol-gel method assisted by citric acid. The structure of the powders is characterized by X-ray diffraction (XRD).The effects of citric acid are analyzed and its optimum amount is determined. Electrochemical tests show that the best sample displays a reversible capacity of 119 mAh/g at 1C rate. Electrochemical impedance spectroscopy (EIS) measurements are performed to analyze the difference of obtained samples. The rate performance is also tested for the best sample, which still keeps well when the current density is raised to 5C rate.

Abstract: Spinel LiMn₂O₄ was modified with Y₂O₃ coating by a chemical process. The crystal structures of the as-prepared samples were investigated by X-ray diffraction (XRD). The charge/discharge characteristics of the modified samples were evaluated at different rates between 3.0 and 4.4V. The discharge capacities of 2.0 wt.% Y₂O₃-coated LiMn₂O₄ are 116 mAh•g⁻¹, 99.7mAh•g⁻¹, 93.3mAh•g⁻¹ and 82.9mAh•g⁻¹ at 0.1C, 0.5C, 1C and 2C rates (at 20^◦C). The cycle abilities improvement of the spinel LiMn₂O₄ coated with Y₂O₃ are demonstrated at elevated temperature (55^◦C) and high rates (2C). From the analysis of electrochemical impedance spectroscopy (EIS), the improvement of cycle ability may be attributed to the suppression on the formation of the passivating films and the reduction of Mn dissolution, which result from the surface modification with Y₂O₃.