Advanced Materials Research Vol. 800

Abstract: Used the heavy oil of Du 84 well 53-55 in Liaohe oil field, the impact factors of the heavy oil emulsion size distribution were analyzed. The higher concentration of emulsifier, the smaller size of average particle emulsion and the particle size distribution tends to be more uniform. With the stirring rate increasing the size distribution tends to be uniform first then tend to be disperse, and the time used would be shorter to reach equilibrium with agitation rate being faster.With prolong of the stirring time the particle size distribution of the emulsion trends to be more uniform. After emulsifier 0.3%LZC-C-02 being added in heavy oil it will become O/W emulsion and the external phase is water and the viscosity of the emulsion is small with good flowability.

Abstract: Birnessite MnO₂ nanosheets were synthesized by self-limiting deposition of KMnO₄ in a facile low-temperature hydrothermal process. The MnO₂ electrode exhibits a high specific capacitance of 169 F g^-1 at a current density of 0.1 A g^-1, good rate capability with a capacitance of 96 F g^-1 even at a high current density of 5 A g^-1, as well as excellent cycle stability with capacitance retention of 94% at 1 A g^-1 after 1,000 cycles.

Abstract: The polycrystalline La_0.62Sb_0.38MnO₃ sample has been prepared by the solid-state reaction method. Structural, magnetic and electrical transport properties have been researched. X-ray diffraction analysis confirms the hexagonal crystal symmetry. Magnetization measurements indicate La_0.62Sb_0.38MnO₃ experienced from paramagnetic to ferromagnetic state transition with decreasing temperature at about 225 K. Resistivity dependences on temperature exhibit metal-insulator transition (MIT), and the maximum magnetoresistance (MR) ratio is about 33 % at temperature of 189 K and magnetic field of 2 T.

Abstract: Er3+:ZnS quantum dots(QDs) were synthesized by hydrothermal process. The structure, morphology and luminescence properties were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. It was found that the Er3+:ZnS QDs are zinc blende structure with an average particle size of about 8 nm. In PL spectra, The broad peak of ZnS NCs located at 400nm was commonly assigned to sulfur vacancies. The intensity of exciting peak and emission peak at of Er3+:ZnS QDs decreased with doping concentration increasing.

Abstract: Polyaniline nanotubes were prepared by electrochemical polymerization polyaniline within the pores of AAO templates and have been open on one ends. The outside diameter of these tubes is determined by the pore diameter in the template used and that the length of the tube is determined by the thickness of the template. Influencing factors include the polymerization potential, current, scanning rates and numbers, solutions. The characterization of the resulting materials was carried out by UV-vis, X-ray diffraction, cyclic voltammetry, scanning lectron microscopy and conductivity measurements.

Abstract: Water-soluble polyacrylamide is commercially available in different domains of industry, such as water purified, paper making, pharmacy, agriculture and oil exploitation. Especially polyacrylamide is used for polymer displacement, which can enhance oil recovery through increasing the sweeping efficiency. Good economic effects are achieved by the industrial application of polymer in various oil fields. However, some problems of the oil-well production and the waste water treatment come forth with the present of polyacrylamide in the production fluid. It is maybe an efficient mean to solve it with the degradation of polyacrylamide. So, this paper reviews the lately development on the research of the degradation of polyacrylamide, especially including ultrasonic degradation, thermal degradation, biodegradation and chemical degradation.

Abstract: Abatract. The enthalpies of dissolution for nitroguanidine (NQ) in dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K. Empirical formula for the calculation of the enthalpies of dissolution (Δ_dissH) was obtained from the experimental data of the dissolution processes of NQ in DMSO and DMF. The corresponding kinetic equations describing the dissolution processes were dα/dt=10^-1.49(1-α)^0.94 for the dissolution of NQ in DMSO and dα/dt=10^-1.59(1-α)^0.90 for the dissolution of NQ in DMF.

Abstract: A fluorine anion modified CuNiAl hydrotalcite (CuNiAl-LDH (F^-)) was prepared for the selective oxidation of glycerol (GLY) using O₂ as oxidant. It was found that the obtained catalyst with typical layer structures of hydrotalcite compounds was an effective heterogeneous catalyst in GLY oxidation. Under the present conditions, the main product was the C₃ oxygenated products of primary alcohol glyceric acid (GLYAC). The highest conversion of GLY reached 32.0% with 58.1% of the selectivity to GLYAC.

Abstract: The formation process of diblock copolymer brushes, formed by the adsorption of flexible chains on the surface is studied by Molecular Dynamic simulations. The surface adsorption density has been distinguished, depending on the various chain structures and counterions. The mode was considered as size ratio of A-block lengths to the the chain length, B-block carries the positive charge, and add counterions to the system. The result shows that the surface adsorption density is affected strongly by ratio of A-block length to the chain length, inhibited by the counterions, which is qualitatively consistent with experiments. These initial findings can be used as a guide for the preparation of actual diblock polymer brushes on metal crystal surfaces membranes by the adsorption approach.

Abstract: We applied ab initio theoretical studies on the complex of C2H4 and 2HX,the results demonstrated that C2H42HX(X=F,Cl,Br,I),with increasing halogen atomic number,from HF to HI,the bond length have all increasing,however,the binding energy of complex present in the overall decreasing trend.The π bond C2H4 molecule at least interacting with 2HX(X=F,Cl,Br,I) to formation of the X-Hπ bond complex.