Abstract: A new surface-plasmon-polariton mode energy extraction method using a deielectric extraction layer (DEL) was suggested. A numerical analysis was conducted to varify the feasibility of the extraction method and to find out the optimal values of the design pararmeters. Refractive index of the DEL should be larger than that of oragnic layers of organic light-emitting diodes. In addition, the thickness of the semi-transparent cathode had an optimal range.
Abstract: Polymer composites reinforced with high strength synthetic fibres have been used for many engineering applications. Environmental and economic issues, encourage the exploration on the introduction natural-synthetic fibre hybrid composites. Mechanical properties are critical to composite performance and may due to the manufacturing process conditions. This study investigates the effect of post curing temperature, natural fibre content and resin-hardener mixing ratio on mechanical properties of kenaf-Kevlar hybrid composites. A full factorial design (23) was carried out to determine the effect these factors on the responses: flexural strength, flexural modulus and impact strength. A statistical study has been performed in order to determine the how the factors affect the responses. The study showed that post-curing temperature, kenaf content and resin-hardener mixing ratio gives significant effects on the mechanical properties of kenaf-Kevlar hybrid composites.
Abstract: In order to save the costs of the rapid hardening and repair sulphoaluminate cement and improve its working performance, the effects of slag, fly ash, silica fume in different contents and different adding ways on the initial setting time and working performance of sulphoaluminate cement are studied. The results show that the initial setting time of single-doped slag and fly ash both meet the requirements of repair materials, but silica fume significantly cuts the cement’s initial setting time short, which does not meet the construction conditions for rapid hardening and repair. Ultimately it is determined that the mechanical properties of sulphoaluminate cement are the best when slag and fly ash are compound added by the content of 30% at 4:1 mass ratio and simultaneously the initial setting time meets the conditions for rapid hardening and repair.
Abstract: An explosive growth of interest has been developed in creating of alternative process of crude palm oil wastewater treatment. Membrane processing offers many advantages as it can be used in almost the stage of oily wastewater treatment. Aim of this study was to investigate nanoporous membrane morphology and performance for refined palm oil wastewater treatment. The comparison of performance and morphology was carried out between neat PVDF and PVDF nanoporous membranes with nanosized TiO2 particles of different compositions. Results of permeability and instrumental analysis illustrated that nanometer size obviously affected the PVDF membranes performance and structure. Smaller nanoparticles could improve the antifouling property of PVDF membrane more remarkably. Cross-section of membranes were observed with a field electronic scanning electron microscope (FESEM). The TiO2/PVDF membrane with smaller nanoparticles had smaller mean pore size on its surface and more apertures inside the membrane. X-ray diffraction (XRD) experiment was also suggested that the addition of 1.0 % TiO2 nanoparticles had stronger effect on crystallization of PVDF molecules, poresize of 34.05 nm, contact angle of 53o and flux of 88.50 L/m2h of poresize. It can be concluded that nanoporous PVDF membrane with adding of TiO2 has better performance for treating refined palm oil wastewater.
Abstract: This article is devoted to the formation of a mechanism of discharge along the surface of a dielectric in sulphur hexafluoride electrode systems in different configurations. The article also addresses to the calculation of the electric field distribution and criteria for increase of discharge along the dielectric surface, depending on the field configuration, pressure and heights.
Abstract: In this paper, CdS sample and phosphotungstic acid/CdS composite materials were prepared by hydrothermal synthesis and impregnation method, respectively. These samples were characterized by FT-IR, XRD and TEM. The characteristic peaks of phosphotungstic acid and CdS appeared in IR spectra of phosphotungstic acid /CdS composite samples. Using the degradation of Rhodamine B and Methylene blue solutions as the model reaction, respectively, the photocatalytic degradation performance of CdS, phosphotungstic acid and their composite samples was discussed under the irradiation of UV light or sunlight. The results showed the degradation effect of phosphotungstic acid /CdS to Rhodamine B and Methylene blue solution was better than CdS under the irradiation of 250 W mercury lamp or sunlight. Composite sample 1 had the best photocatalytic activity and its degradation rate on Rhodamine B was 85.2 % at 120 mins with pH 3.5 under sunlight, and the degradation rate of Methylene blue reached about 92.1% at 120 mins with pH 6.0 under sunlight.
Abstract: In this paper, the stiffness mechanical property of natural fiber reinforced thermoplastic composites is analyzed using composite micromechanical model. Kenaf natural fiber is selected as the reinforcement material in the composites construction while three types of commonly used automotive grade thermoplastic matrices, namely polypropylene, acrylonitrile butadiene styrene and polyamide 6 were selected to be reinforced with kenaf fibers. Their stiffness property was later analyzed using Halpin-Tsai micromechanical model at varying fiber content and fiber aspect ratio conditions. In all cases, theoretical results show that the kenaf reinforced thermoplastic composites stiffness increased linearly as the fiber contents were increased. Apart from that, results also show that the stiffness property also increases as the fiber aspect ratio was increased. Higher final composites stiffness property was also observed as stiffness matrix material is utilized in the composites formulation. The prediction results also provided valuable and quick insight as well as cost effective alternative to composite designers in assessing the stiffness performance of natural fiber composites especially those which are reinforced with thermoplastic matrices compared to conventional experimental technique for automotive product development purposes in addition to identifying the optimal parameter to be put into focus in their composites design to achieve the intended design performance specifications.
Abstract: The effects of synthesized silver nanoparticles on electrospun PHBV ultrafine fibers were studied by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). Addition of silver nanoparticles increased from 0.1% to 2.0%, the sooth ultrafine fiber with an average diameter of about 2 μm formed a non-woven mat was obtained. DSC showed the efficient heterogeneous nucleation by the silver nanoparticles for facilitating PHBV crystallization.The thermal stability of the PHBV/Ag ultrafine fibers improved with the increase in the content of the silver nanoparticles.
Abstract: Different kinds of mesoporous carbon materials can be obtained through the use of different templates or control condition. The study describes the adsorption behavior of dyes such as rhodamine B, methylthionine chloride and reactive red from aqueous solution using ordered mesoporous carbon in different pore size distribution. In this study, the method of controlling the aperture of ordered mesoporous carbon is changing the mass ratio of the revised template and carbon source. Ordered mesoporous carbon was synthesized with the evaporation induced self-assembly method in different proportion of template agent (F127) and phenolic resin and employed to evaluate the effects of initial concentration, contact time, pH and temperature on the removal of dye solution in batch experiments. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption-desorption. These analyses reveal that the mesoporous carbon have ordered structure. The experimental results indicated the ordered mesoporous carbon in different pore size distribution showed significant differences in the adsorption of different dyes and it was provided with an excellent selective adsorption.