Advanced Materials Research Vols. 641-642

Abstract: The aging and shear rejuvenation behavior of a commercial printing ink have been studied experimentally using creep and oscillation modes. We observed that the printing ink has typical rheological characteristics: time-dependent, reversible and shear-thinning viscosity. Meanwhile, these properties are very strongly influenced by shear history, thus employing pre-shearing to obtain a standard test state is of vital importance. After pre-shearing, the quiescent ink undergoes structural evolution, i.e., aging, including a sol-gel (liquid-solid) transition on the early stage at room temperatures, the higher the temperature, the earlier the sol-gel transition occurs. The degree of aging and shear rejuvenation can be characterized by the waiting time after pre-shearing and the stress dependence of the power-law index. Finally, we use a time-stress superposition to obtain a universal master curve which is able to describe the aging behaviors of the printing ink. This study shows that the aging processes of printing ink for different waiting times are self similar, variation of waiting time just change the time scale and elastic modulus.

Abstract: For developing the high efficiency and new-style CO₂ absorbent, the CO₂ absorbing ability, separating performance, causticity to steel and decomposition performance were studied and contrasted for various kinds of absorbent. It was suggested that 12%MEA+7.5%AMP is the best composite absorbent. The rich liquid regeneration temperature is 100°C. Adding 1% sodium metavanadate could reduce the corrosion and decomposition.

Abstract: A detailed singlet potential energy surface survey on the ¹CF₂ + ³O₂ reaction is carried out in order to clarify the reaction mechanisms of the singlet difluorocarbene (¹CF₂) with oxygen (³O₂) at the B3LYP/6-311++G(d,p) level. To determine the accurate energies of all stationary points, the QCISD/6-311++G(d,p) single-point calculations are done by using the B3LYP/6-311++G(d,p) optimized geometric structures. The title reaction is important in high temperature processes. Four product channels, P₁(F₂ + CO₂), P₂(F₂O + CO), P₃(2F + CO₂) and P₄(FCO + FO), have been found in the ¹CF₂ + ³O₂ reaction. P₁(F₂ + CO₂) and P₃(2F + CO₂) have comparable contributions to the title reaction and they are more favorable than the other two thermodynamically and kinetically.

Abstract: The thermal decomposition kinetics of RDX at different rates was studied by thermogravimetric analyzer(TG) and the activation energy of RDX was calculated by distributed activation energy model. It is shown that the thermal decomposition processes of RDX were divided into three stages according to the TG curves, they are molten stage, thermal decomposition stage and eng stage. The activation energies of RDX are all between 124.34 and 181.48KJ•mol-1 in the thermal decomposition stage of non-monotonously increasing. The activation energy of RDX is 139.98 KJ•mol-1 in the molten stage, and the thermal decomposition stage is167.24KJ•mol-1.

Abstract: L-α-glycerophosphocholine, transesterification, tert-butylamine, natural lecithin Abstract. Tert-butylamine was confirmed as effective catayst for preparing L-α-glycerophospho -choline at mild conditions. The process using this catalyst would be much simpler, since the recovery of the catalyst can be combined with the recovery of methanol by distillation. The conversion of phosphatidylcholine could reach over 98% after 4 h, with a catalyst content of 2.4% under 60 °C. The mechanism of the methanolysis reaction was proposed and the experimental data fit the equation model well. GC was used to analyze the product, it was indicated that the product had high purity, and the catalyst could get similar effect to the fresh after repeatedly used.

Abstract: The objective of this agricultural geochemistry survey project was to study the enrichment distribution of Cd, Pb and Hg in the agricultural soil in Mianyang City, sichuan Province China. More and more geochemists in field of agricultural geology become to concern heavy metal (Cd, Pb and Hg) pollution problems in soil. Basing on geochemical investigation method, and employing remote sensing ( RS ) and geographic information system (GIS) techniques and methods, it indicates that the distributions of soil Cd, Pb and Hg are controlled by the terrain and landform features, and human constructions in working site. The study shows as well that distributions of Cd, Pb and Hg contents are influenced by highway and river, and there is enriching tendency of Cd in the project site with the risk of contamination.

Abstract: This paper present the optimum conditions for treating oily sludge with organic solvent extraction and surfactant solutions using the single factor experiment. Firstly, selecting petroleum ether (boiling range is 60-90oC) as the organic solvent, then selecting the mixture of sodium dodecyl benzene sulfonate and alkylphenol ether(OP-10) as surfactant agent to extract residual crude oil. Results obtained through experiments, the optimum parameters of petroleum ether were that ultrasonic reaction temperature was 55 oC, ultrasonic intensity was 320W, ultrasonic extraction time was 5min, liquid/solid mass rate was 7.5, then under the optimum conditions, the residual oil rate was about 6%. While the optimum parameters of surfactant mixture were that the temperature was 55 oC, ultrasonic intensity was still 320W, ultrasonic extraction time was 10min, liquid/solid mass rate was 15, under the optimum conditions, finally the residual oil rate was only about 1%.

Abstract: Abstract: In order to study the possibility of separating ethyl acetate and isopropanol by extractive distillation with ILs as an entrainer. Isobaric vapor-liquid equilibrium data for ethyl acetate + isopropanol+1-octyl-3-methylimidazolium tetrafluoroborate ([OMIM]BF4) ternary system at 101.32 kPa were determined using a recirculating still. The results showed that the ionic liquid (IL) studied produced a notable salting-out effect, which enhanced the relative volatility of ethyl acetate to isopropanol and eliminated the azeotrope when the mole fraction of IL in the liquid phase was greater than 0.10. Therefore, [OMIM]BF4 can be used as the extraction agent of extractive distillation for ethyl acetate + isopropanol systerm, the suitable mole fraction of [OMIM]BF4 is about 20%. The experimental data were correlated with the NRTL model, the correlated results agreed well with the experimental data.

Abstract: The objective of this study was aimed to investigate the COD removal from biologically treated coking wastewater with a multiple barrier process of coagulation-flocculation (CF)/Fenton oxidation (FO)/ powdered activated carbon (PAC) adsorption. Optimized parameters validated by a series of processes were found to be FeCl3 concentration of 320.0 mg/L, anionic polyacrylamide (APAM) of 0.8 mg/L, the mass ratio mH2O2/mFe2+ of 4.7 and 500.0 mg/L of PAC, respectively. The total COD removal of 88.1% was obtained. Furthermore, through GC/MS analyzing of treated coking wastewater by stages, which was consistent with the COD removal. The results showed that the effluent treated by the integrated processes could meet the national second-grade standard of sewage comprehensive discharge in China and the requirements of reverse osmosis (RO) feed water. This implied the multiple barrier method had promising in practical applications.

Abstract: Au nanoparticles supported on MgAl-LDHs has been synthesized by coprecipitation method, gold colloid routs as well as intercalation and assembly method respectively. The influence of the above different preparation methods on the activity of the gold catalysts for CO oxidation was investigated, and the phase and gold particle size distribution of the catalysts were analyzed by XRD and TEM respectively. The results show that 100% conversion of CO on the fresh prepared gold catalysts synthesized by gold colloid routs and intercalation assembly method can be achieved at room temperature when the catalysts were activated at 473K for 2h in the air. The gold particle size distribution was range from 2nm to 7nm.