Applied Mechanics and Materials Vols. 548-549

Abstract: Silica-modified polyaniline (SM-PAni) were deposited on glass and platinum-coated glass substrates via oxidative polymerization. Zinc sulfide (ZnS) were grown on top of SM-PAni films by chemical bath deposition. The surface and optical characteristics were investigated. SEM micrographs revealed the formation of SM-PAni nanostructures and ZnS nanospheres. Increase in nanosphere sizes were observed when Pt-coated substrates were used. UV-Vis spectra showed that SM-PAni/ZnS nanocomposites grown on both substrates exhibit good absorbance in the visible and ultraviolet region which is a good indication for potential solar cell application. Better absorbance in the ultraviolet region was observed when Pt-coated substrates was used. Vibrational peaks observed in FTIR confirmed the presence of SM-PAni particles.

Abstract: Produced Water (PW) is a byproduct in the production of oil and gas. With various types of heavy metals and pollutants, it may harm human being and marine life. The objectives of this study are; 1) to study the performance of the fabricated membranes and 2) to verify the results by using the experimental design. The PW samples which is from Dulang field is treated using Polysulfone membranes that prepared by casting solutions consisting of polysulfone (PSf), N-methyl pyrrolidone (nmp), Bentonite, and polyvinyl pyrrolidone (PVP). The influence of PVP (0-7wt%) and Bentonite (0-7wt%) addition were investigated in terms of PW Flux (mL/cm²h) and TDS rejection rate (%). The amount of TDS in PW sample is 12g/L and the PSF membrane successfully reduced it up to 14%. The experimental results then used in Central Composite Model (CCM) under RSM which designate parameters (X) as Operating Pressure (bar), PVP (wt%) and Bentonite (wt%) to compute the optimum response condition (Y) as PW Flux and and TDS rejection rate in Design Expert software. The optimum condition achieved by PSf membrane is where the composition of 4.5wt% PVP, 6.0wt% Bentonite and Operating Pressure of 5.0 bar were used. Both methods showed the value of TDS decreased up to 14% after run through the membranes for several hours. Experimental and predicted result (DoE) for optimum condition is then compared to verify the error. The percent error calculated is 2.4% and 25.5% for PW Flux and TDS Rejection Rate respectively.

Abstract: In this research, we study the magnetic attenuation of the superconducting cylinders by Beer-Lambert modified model. In optics, the Beer-Lambert model relates the absorption of light to the properties of the material through which the light is traveling. We modified Beer-Lambert model to describe behavior of magnetic field attenuation by superconducting cylinders. The penetrate field and London penetration depth are derived analytically. Finally, the attenuation of applied magnetic field is investigated and applied to cylindrical superconductors.

Abstract: In this paper, we represent analytical solutions of transient velocity for electroosmotic flow (EOF) of generalized Maxwell fluids through both micro-parallel channel and micro-tube using the method of Laplace transform. We solve the problem including the linearized Poisson-Boltzmann equation, the Cauchy momentum equation and generalized Maxwell constitutive equation. By numerical calculation, the results show that the EOF velocity is greatly depends on oscillating Reynolds number and normalized relaxation time.

Abstract: The tribological properties on the friction and wear properties of cast iron CrMo and 38CrMoAlA materials under the load, temperature, sliding speed were investigated on a MMW-1 high temperature friction-wear tester. The worn surface morphology was observed and analyzed by scanning electron microscope (SEM). The results show that considering the impact of the three factors, the conclusion was that larger influence on adhesive wear was mainly test temperature and sliding speed, the influence of the load was minimal. The main influence of test temperature and sliding speed was adhesive wear. The abrasive wear and plough cut wear were mainly caused by the load. When the synergy of the load, temperature and sliding speed reach a certain condition.

Abstract: To improve the impact of fly ash on the properties of cement-fly ash stabilized crushed stone, and promote it popularize and apply better. This paper investigated the effect of fly ash content on unconfined compressive strength, cleavage strength and resilient modulus of cement-fly ash stabilized crushed stones, and those relationships between mechanical parameters. The results showed that with increasing of the fly ash content, the unconfined compressive strength and cleavage strength increased at first, then decreased, the resilient modulus decreased, and The brittleness index increased. We can conclude that the optimal fly ash content is between 10% and 15%, and increment of fly ash content can improve its crack-resistance.

Abstract: In this study, the use of fire retardant, stain mixed solution using heat, pressure processing poplar veneer, the use of orthogonal experiment to determine the optimal technology mix rationale for poplar veneer: processing retardant, stain veneer process optimization flame retardant concentration of 20%; dye concentration of 0.5%; retardant treatment time 60min.

Abstract: The effect of copper contents on the microstructure and mechanical properties of A319 aluminium alloy in thixoformed conditions was investigated. The results showed that the addition of 1 wt. % and 2 wt. % copper to A319 alloy reduced the fraction liquid sensitivity and enlarged the working window temperature. Based on the differential scanning calorimetry (DSC) data, the curve of the fraction liquid versus temperature was constructed for each alloy, indicated the temperatures corresponded to the fraction liquid of 30% and 50%. It was found that the working window temperature for A319 alloy of 7 oC increased to 12 °C when 2 wt. % copper was added, while the sensitivity decreased from 0.027 °C^-1 to 0.016 °C^-1.The alloy feedstocks produced by cooling slope casting were thixoformed successfully at 40% fraction liquid. The thixoformed A319 alloys attained a hardness level as high as 118.2 ± 2.5 HV when 2 wt. % copper was added.

Abstract: Under-deposit corrosion in cooling water system is often found in industries. The under-deposit corrosion rate in cooling water system is rarely found in a literature. The mechanism depends on the metal, types of deposit and corrosive species in the cooling water system. In this study, the under-deposit corrosion rates of carbon steel in cooling water at various times were determined by weight loss, profilometric and electrical resistance methods at 40C. From this experiment, these three methods showed the consistent results. The under-deposit corrosion rates of carbon steel were about 0.1-0.2 mm/y.

Abstract: To produce 130MPa reactive powder concrete with iron tailing sands as aggregation in an economic hot curing system, the effects of curing temperature, curing time and curing conditions on the reactive powder concrete was studied, the reasons of the strength of reactive powder concrete in different curing systems has the difference from the submicroscopic structure point of view was analyzed. The results show that use 90°C hot water to cure reactive powder concrete for 48h can lead it’s 28 day compressive strength reaches 140MPa, the flexural strength reaches 28MPa.