Abstract: Electroreduction of acrylonitrile in ionic liquid BMimBF4 was studied to find a new green process for producing adiponitrile. Effects of cycling times, acrylonitrile concentration and water concentration were determined by cyclic voltammetry. One reduction peak of acrylonitrile was determined in first cycle and second reduction peak was determined after scanning 4th time. Currents of second reduction peak increased with adding scanning times. Peak current increased with increasing acrylonitrile concentration and water concentration. Peak potentials of voltammograms shifted to negative when increased acrylonitrile concentration, while it had reverse trend with increasing water concentration.
Abstract: Barium oxide was introduced to modify Palladium catalysts supported on CeO2–ZrO2-La2O3-Al2O3 (CZLA) by impregnation and co-precipitation. methods. Various techniques, including X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS), were employed to characterize the physicochemical properties of BaO-modified Pd-only catalyst. Catalytic activity for methanol, CO, C3H8 and NO conversions showed that BaO-modified catalyst prepared by impregnation method exhibited the best performance for methanol, C3H8 and NO removals, while the catalyst prepared by co-precipitation method was in favor of CO oxidation. Combined with the results of XRD, H2-TPR and XPS, it is concluded that the co-existence of PdO and Pd-O-Ce active species by impregnation played an important role in the methanol, C3H8 and NO removals, while the higher dispersion of palladium and improved reducibility were mostly favorable to the CO oxidation. The conversion of NO was co-effected by tow active species and the formation of Ba2AlLaO5 mixed oxide.
Abstract: Changing the proportion of NBS and porphyrin, dibromination of β, β’- π-extended porphyrins was found to selectively occur to the β and β’ position of the porphyrins which is antipotal to the fused aromatic ring. Subsequent Sonogashira coupling of the resultant dibromoporphyrin introduced a carboxylphenylethynyl group to the π-extended porphyrin and the π conjugation was thus further elongated. The coupling products have shown a broadening and a red-shift of the Soret band and Q bands in the UV-Vis absorption spectra compared with the π-extended porphyrin starting materials and the original unmodified porphyrins.
Abstract: A novel complex was obtained by self-assembly of the corresponding alkaline earth metal chlorate with a ligand, Azobisisobutyronitrile in this paper. The coordination principle of the as-prepared complex was analyzed firstly, and then its structure and thermal behavior were detected by the infrared spectrogram and TG-DTA
Abstract: 1-(2-Methacryloyloxy)ethyl-3-butylimidazolium bromide, a kind of functional ionic liquid containing ester group, was synthesized by two synthesis methods, denoted as thermal heating method and ultrasonic-assisted method. The optimal synthesis condition of the thermal heating method is discussed. Comparison of the two methods shows that ultrasound significantly enhances the efficiency of the reaction. The ultrasonic-assisted method is quite promising in synthesis of ionic liquids with mild condition and high efficiency.
Abstract: In this study, a new starch graft copolymer dispersant for Chinese Shenhua coal-water slurry (CWS) was prepared by radical polymerization using styrene sulfonate (SSS), hydroxyethyl acrylate (HEA) and methyl acrylic acid (MAA) as graft monomers in oxidation-reduction initiator system. The apparent viscosity, static stabilization and rheology of Shenhua coal-water slurry prepared with the dispersant have been were investigated. The experimental results demonstrate that the CWS gives the minimal viscosity of 826 mPas at coal concentration of 66 wt%, dispersant dosage of 0.5 wt% and shear rate of 100 s-1. Bleeding ratio tests indicate the starch graft copolymer can stabilize the slurry. The rheological behavior of the prepared CWS can be described by the pseudo-plastic fluid model. On the basis of the above, the starch graft copolymer dispersant has broad prospect for the application for CWS.
Abstract: A new type of graft copolymer, sulfonated humic acid-acrylic acid resin (SHA), was synthesized and developed as dispersant for highly-loaded coal water slurry (CWS) from Chinese Binchang coal. In this study, The formulation, stability and rheology of the slurry with SHA were investigated. The experimental results show that SHA can reduce effectively CWS viscosity at low dosage, and that the CWS with SHA has excellent stability within 48 h and exhibits shear-thinning apparent viscosity/shear rate behavior. Based on the above, SHA is a promising dispersant for highly-loaded CWS in the practical use in industry.
Abstract: By molecular dynamics method, the tensile processes of nano-single crystal copper with the type I crack under different temperature were simulated, and the effect of different temperature to crack propagation mechanism was analyzed. The results indicate that the temperature has significant effect on crack propagation mechanism of nano-single crystal copper. While the crack is the intrinsic brittle cleavage extension under low temperature and room temperature, the twin crystal is not easily to generate; whereas, dislocation climb caused twin crystal belt appears near the crack tip under high temperature. With load increasing, the length and the width of twin crystals belt increase gradually, and the existence of the twin crystal belt causes the crack branch change to the extending direction.
Abstract: "HaiYangShiYou 115" chain cable in use process was found in more broken wires. Through the chemical composition analysis, mechanical property testing, fracture analysis, metallographic examination methods, the cause of the broken wire are analyzed. The results show that: the material of steel cable anchor chain mechanical performance is basic comply with the design requirements, the broken wire fracture is relatively serious wear, all send the samples of the present wear trace shape is consistent, should be the same kind of wear the way by damage, and reduced the steel wire tensile strength, lead to fracture .
Abstract: Density functional theory (DFT) calculations were performed to investigate the structures of bromo silsesquioxanes Si2nO3nBr2n (n=1-5). Our study focuses on the structures, stabilities, and electronic properties of the bromo silsesquioxanes. The large HOMO–LUMO gaps, which range from 4.43 to 6.62 eV, imply optimal electronic structures for these molecules.