Advanced Materials Research Vols. 455-456

Abstract: A new photochromic diarylethene compound, 1-(2-methyl-3-benzothiophene)-2- [2-methyl-5-(2-pyridine)-3-thienyl] perfluorocyclopentene (1a) was synthesized. its photochromic and fluorescent properties have been investigated in detail. It showed good photochromism both in solution and PMMA amorphous film upon photoirradiation. Its fluorescence properties in the solution also were reaearched.

Abstract: We investigate modes excitation with input field of different positions in three-mode photonic crystal waveguides. The three-mode photonic crystal waveguides is formed by removing three rows rods in 2D photonic crystals. The input field with different positions can excite different modes due to the field intensity distribution of modes. When the input field locates at the position of the zero field intensity of the waveguide mode, the mode can not be excited. The finite-difference time-domain method is used to obtain the excited field distributions.

Abstract: Ni/Al₂O₃ nanoparticles with core-shell structure were fabricated by a new route for electroless nickel plating. It is found that ultrasonic radiation can promote the plating reaction more efficiently. The Ni-coated Al₂O₃ composite powders with a core-shell structure were synthesized and the thin Ni layer on the a-Al₂O₃ powder was about 5 nm thick. However, during electroless nickel plating without ultrasonic wave treatment, a core-shell structure was also formed, but aggregation of the particles and self-decomposition were observed.

Abstract: Wood because of its unique texture, color, smell has a good affinity with the people is to improve the living conditions of very rational ship materials, Can the wood material applied on a large surface ships, the key is fire prevention. This will be the leading domestic and foreign varieties of fire retardant wood elaborated, And proposed development and application of wood composite materials, to improve the habitability of large surface ship design and improve work efficiency and thus improve the ship crew the importance of fighting; The flame-retardant composite sheet material of biomass improved formulations, which can effectively achieve the fire retardant requirements of large surface ships, ultimately achieving the purpose of the application of the ship.

Abstract: Thermo gravimetric analyzer was used to investigate the thermo-gravimetric behavior and the exothermicity of molybdenum concentrate roasting. Roasting reaction mechanism of molybdenum concentrate was concluded with the double extrapolated method. Data processing and fitting was constructed with the integral methods of Costs-Redfern and Flynn-Wall-Ozawa, and roasting reaction kinetic parameters were proposed. The results showed that roasting reaction process of weight loss was divided into four stages, namely preheated drying stage, diffusion stage, rapid reaction stage and deep oxidation stage respectively. The heat released from the oxidation reaction mostly concentrated in the rapid reaction stage, the main product of this stage was MoO₂, and the activation energy was 227.7kJ/mol. The main product of deep oxidation stage was MoO₃. When the temperature was about 600°C, the formation rate of MoO₃ was maximum, less heat released at this stage and the activation energy was 163.2kJ/mol.

Abstract: Ultrasonic cavitation is at the origin of kinetics and yield improvement of ultrasound-assisted chemical processes. Character of ultrasonic field plays a potential role in choosing the best conditions for ultrasound-assisted chemical processes. In this paper, acoustic field distribution was measured with a thermoelectric probe in a 500mL flask filled with distilled water. A 40kHz ultrasonic horn was used and the temperature signal was measured at different locations, including axial and radial directions along the horn. The immersion depth of ultrasonic horn was investigated with ultrasonic power at 250W and 300W. We concluded that at the same power, when the immersion depth was 3cm, the intensity reached maximum.

Abstract: Using the Fiber Quantity Analyzer (FQA) for analysis of the paper pulp fiber moving in the Cylindrical Hydrocyclone, making use of the way of Limited Element Analysis and Calculation Fluid Dynamic for the numerical simulation of the velocity distribution of moving process. Based on the mathematic model of it, point out the idea of design on the geometric parameters of the cylindrical hydrocyclone. The result show, the suit length of pole is benefit to improve the machine handle ability and separation efficiency.

Abstract: . A one-dimensional mathematical model was developed for describing heat and mass transfer process of lump coal falling in the freeboard zone of COREX melter-gasifier. The temperature distribution, law of moisture evaporation and removal of volatile of lump coal were obtained. Further more, the effects of operating parameters on heat and mass transfer phenomena of lump coal were studied.

Abstract: This work presents a novel method for the synthesis of cuprous chloride (CuCl) catalyst. The CuCl powder is prepared by one-step cocurrent flow reaction of CuSO₄·5H₂O with NaCl in a thermostatic water bath at different reduction temperatures of 45 °C, 50 °C and 60 °C. Sodium bisulfite and sodium carbonate are fed in parallel into a flask in 40 to 60 minutes and with a mole ratio of 4:1. Thereafter, the prepared powder is characterized. The result of X-ray powder diffraction (XRD) shows that the powder consists of CuCl with well crystallization. Scanning electron microscope (SEM) images indicate that the morphology of the samples exhibits a regular 2D flake structure. In addition, results of BET and BJH methods show that the CuCl powder has a larger surface area. The CuCl catalyst is used for the reaction of silicon with ethanol to produce triethoxysilane and tetraethoxysilane and thereby its activity is evaluated. It is found that the reaction selectivity to triethoxysilane depends on the amount of the catalyst. Finally, based on the results obtained the reaction mechanism on the silicon surface is proposed.

Abstract: In the presented work, the carbon nanotubes (CNTs) were successfully wrapped with alkli lignin. Both transmission electron microscope (TEM) and scanning electron microscope (SEM) observations show that the CNTs are coated with a layer of lignin, which is also verified by Raman spectra. SEM images demonstrate that lignin-wrapped CNTs (lignin-w-CNTs) can more uniformly dispersed in ABS matrix relative to pristine CNTs. Moreover, compared with CNTs and lignin, incorporating lignin-w-CNTs results in slightly higher tensile stress at the same loading level.