Advanced Materials Research Vols. 608-609

Abstract: Ultrathin multilayer films containing polyoxometalate (POM) K₁₁[Eu(PW₁₁O₃₉)₂] (Eu(PW₁₁)₂) and poly(amidoamine) (PAMAM) dendrimer were prepared using layer-by-layer (LBL) assembly method in the present work. The stable multilayer films were assembled by alternate adsorption of negatively charged POM and positively charged PAMAM from their aqueous dispersions. The growth of the muhilayer films is regular．The proposed novel immobilized method exhibited good stability and the photoluminescent behavior of films at room temperature was investigated to show the Eu³⁺ charaeteristic emission pattern，which is important for practical application.

Abstract: Polyaniline nano particles and polyaniline/polyurethane composite film were prepared through the template-free method. The ordered array structure of composite thin films with optical property were observed. The proportion of polyaniline/polyurethane in the composite films was discussed, and the change of resistance and absorbance of the thin films was measured in different proportion. In the energized condition polyaniline/polyurethane composite film had morphological changes, shrink trend, and their resistance value became significantly increasing. With the increase of the voltage electricity, the film contraction trend changed bigger.

Abstract: The influence of annealing under different conditions on CdS films after CdCl2 post-growth treatments was investigated. The crystalline quality of CdS films was improved after the treatment with CdCl2 at 400°C in N₂.

Abstract: CO₂ pre-cooling dual nitrogen expander liquefaction process was proposed for the LNG-FPSO unit and compared with propane pre-cooling dual nitrogen expander process and mixed refrigerant pre-cooling nitrogen expander process by simulation. Gas property sensitivity of the process was analyzed from the thermodynamic point of view. And offshore adaptability of the process was evaluated. The results show that the process will be suitable for mid to large-scale LNG production in severe sea condition. And it will be not sensitive to the changes of gas temperature, pressure and composition.

Abstract: As the first step in coal combustion and gasification, coal devolatilization has significant effect on reaction process. Previous coal devolatilization models have some disadvantages, such as poor flexibility, model complexity, and requirement of characterization parameters. Recently, Sommariva et al. have proposed a multi-step kinetic model of coal devolatilization. This model avoids the disadvantages mentioned above and can predict elemental composition of tar and char. In this paper, the mechanism of this model has been revised for simple application to Chemkin. Revision method is that some reactions are split into more reactions by using one pseudo-intermediate-product to replace several final products. Simulation results show that calculation results from revised mechanism compare quite well with that from original mechanism and have good agreement with experimental data. The revised mechanism is accurate and can be applied to Chemkin very easily, which gives it wide application to simulation of coal pyrolysis, gasification and combustion.

Abstract: Active carbon (AC) supported Ni–Cu bimetallic catalysts for the direct synthesis of acetic acid (AcOH) from CH₃OH and CO were synthesized and investigated. The synthesized catalysts were fully characterized using surface comparator and scanning electron microscopy (SEM) techniques. The catalytic activities were investigated by the initial experiments. The experimental results showed that Ni–Cu /AC catalysts were efficient for the direct synthesis of AcOH. The conversion of CH₃OH was higher than 15.7 % .

Abstract: After oil spills in the coastal aquatic environment, the physical and chemical properties of the spilled oil may change under the influence of the chemical dispersant and form emulsions in the water. This paper presents the results of a laboratory study on the influence of chemical dispersant to the properties of crude oil. The experiments were conducted using two widely-used surfactant GM-2 and BH-X, two crude oil samples and artificial seawater. Density, viscosity and emulsification rate of crude oil with different amounts of dispersant added was measured. The results show that viscosity of the crude oil was highly influenced by the chemical dispersant. The maximum emulsification rate of the Saudi Arabian middle crude oil was 54.1% and 57.4% with the dispersant to oil ratio above 0.8, whereas the emulsification rate of the heavy oil was significantly lower than the middle oil with both of the two types of chemical dispersant.

Abstract: A new cationic bleach activator (CBA) N-[4-pyridmoniomethyl)benzoyl]caprolactam bromide (PBCB) was synthesized and evaluated in a hot peroxide bleaching process. The effects of time, temperature and the concentrations of hydrogen peroxide and activator on the bleaching of cotton fabric were investigated using an orthogonal experimental method. The optimal bleaching process of PBCB-activated peroxide system was 5g/L H2O2, 0.5g/L CBA, 40°Cand 45min dwell time under neutral pH, with which a whiteness equivalent to that of the conventional-bleaching system was achieved, but the PBCB system resulted in almost no fiber damage based on fabric strength.

Abstract: This document explains and demonstrates the problem of HOCH₂CH₂OCH₃, Na and CH₃OCH₂CH₂OC₂H₅, factors of CH₃OCH₂CH₂OC₂H₅ a yield influence degree order: reaction temperature>C2H5Br consumption> etherification reaction time, comprehensive single factor experiment and orthogonal experiment results, and concludes that the C₂H₅Br, sodium metal and CH₃OCH₂CH₂OH is a laboratory CH₃OCH₂CH₂OC₂H₅ a the best conditions for, C₂H₅Br : Na (mol ratio) = 1.4, reaction temperature 80 °C, reaction time is 3.5 h.

Abstract: To control the serious pollution caused by alkaline pulping in paper industry and utilize alkali lignin – the main organic ingredient residing in black liquor, an experimental research on hydrothermal oxidation of industrial alkali lignin for producing small molecule organic acids (mostly formic and acetic acids) was conducted using batch reactors. The results showed that the yields of acetic acid almost entirely increased and then decreased with oxygen supplies, reaction times and reaction temperatures, while the yields of formic acid fell in a narrow range of ~ 4% irrespective of all the hydrothermal conditions. A highest total yield of formic and acetic acids of 23.0% was achieved at the conditions of 300 °C, a 100% oxygen supply and a 60 s reaction time, and at the same time a highest yield of acetic acid of 20.3% was obtained. Based on the products recognized, the main pathways for producing small molecular organic acids, particularly formic and acetic acids were discussed.