Advanced Materials Research Vols. 622-623

Abstract: A combination of controlled random search method and geometry modification concept is used to minimize the root mean square level of structure borne sound for a model. The structure is a rectangular plate made of steel. A specific frequency range for this porpuse is considered. The results show that this approach could produce significant reduction in the value of radiated sound power level of the structure within a limited time.

Abstract: Acetylferrocene was synthesized by acetyl chloride and ferrocene as raw materials, dichloromethane as the solvent, and ZnO as catalyst. Response surface methodology based on three-level, three-variable central composite rotable design was used to evaluate the interactive effects of the ratio of acetyl chloride and ferrocene(2-4), the amount of ZnO(1.0-1.3mol), reaction time(30-60 min)on the percentage yield of acylferrocene. The optimal raw material ratio, amount catalyst, and reaction time was 3:1, 1.19mol, 40min. Under the optimum conditions, the actual experimental yield can reach 86.72%.

Abstract: The level of performance of intelligent community is greatly promoted by the development of networking technologies. Some researchers obtained the achievement of intelligent community by utilizing complex algorithm and advanced equipment that makes the solution very expensive. Our research aims to find out a way to intellectualize residential community that is easy to implement, highly reliable and cost-effective. In this study, we present a system which consists of three layers based on the ring topology. For reliability and the ease of maintenance, we propose an automatic fault detection and handling function that is able to quickly detect any fault of the circuit and automatically eliminate the issue. Experiment results demonstrate that the proposed system is extremely efficient, intelligent, and environmentally friendly while being highly reliable and affordable.

Abstract: The study aims to recover copper minerals from a high content of slime and refractory copper oxide ore by flotation process. Based on the research on the properties of the material, the grinding fineness and reagent system are investigated and a technological flow sheet consisting of one roughing flotation, two concentrate flotation, three scavenging flotation and one concentrate-scavenging flotation is adopted. The optimum parameters of flotation experiment are determined as grinding fineness of 90%, dosage of CHO at 200 g/t, dosage of Na2S at 800 g/t and dosage of isoamyl xanthogenate at 1200 g/t. Under such a condition, a copper recovery of 75.03% with a concentrate grade of 18.01% is obtained，which provides a new way for separating the refractory copper oxide ore attached high content of slime.

Abstract: The samples with nominal composition of Bi_1.6Pb_0.4Sr₂Ca _2-xDy_x Cu₃O_y where x = 0.000, 0.025, 0.050, 0.100 and 0.200 were prepared by the co-precipitation (COP) method. The samples were characterized by x-ray diffraction, electrical resistivity measurement and critical current density. The critical current density (J_C) and superconductivity transition temperature (T_C) of Dy substituted were found to be lower than the Dy-free sample. The T_C values vary between 100 K and 75 K toward Dy concentration due to a small change of carrier concentration. The highest TC in Dy-doped sample was found at 96 K in x = 0.025. The J_C decreased towards Dy substitution, and it was measured to be 5751.2 mA/cm2 in Dy-free and 3769.8 mA/cm² in x = 0.025 at 77 K. XRD analysis showed the substitutions of Dy reduced the volume fraction of the 2223 phase and increased the volume fraction of the 2212 phase. The proportion of Bi-2223/Bi-2212 (%) were estimated from 76.74/23.26 in Dy free to 18.90/81.10 in x = 0.200.

Abstract: This research explores the potential for developing responsive composite materials with sensing, kinetic and luminous capacity for application in the design of responsive architectural morphing skins. We integrate sensing devices and building skin as one 'integrated' entity, eliminating the need to embed discrete components in a vulnerable system. This investigation develops and explores the properties and performance of a new material, Lumina for application as a lightweight, flexible and economical luminous architectural skin that responds to proximity and lighting stimuli. The design exploration uses silicone rubber, glow pigments, embedded physical computational and shape change material. It is controlled using parametric design processes.

Abstract: Erbium doped borotellurite glass has been identified as one of the most potential candidate for optical applications due to their excellent in physical and chemical properties. Therefore, the aim of this study is to identify the optical properties by mean of their UV-Vis and photoluminescence spectroscopic of the Er³⁺ doped borotellurite glass. In this work, erbium doped borotellurite glass, (80-x)TeO₂-10 B₂ O₃-10PbO-xEr₂O₃, where 0.5 mol % x 2.0 mol % has been successfully fabricated by using melt-quenched techniques. The glass obtained is in good quality since it shows no sign of devitrification. The glass sample has undergone some physical and optical measurements. From the XRD results, it confirms that the glass is in amorphous nature. Meanwhile, it is found that the density of the glass sample increases from 4.4187 gcm^-3 to 4.5769 gcm^-3 with respect to Er content. For the optical properties, the absorption spectra were measured by UV-Vis-NIR spectrophotometer in the range 400-900 nm interval. From the absorption spectra, the 650 nm excitation wavelength is found to be the most predominant peaks. From the photoluminescence spectra, five significant emission peaks have been observed where by four of them is in the visible regions which is corresponds to 440 nm, 486 nm, 520 nm and 650 nm wavelength while the other one is in NIR regions at 794 nm. Some other results were also been analyzed and presented.

Abstract: Borate glass has been identified as one of the potential host for optical application. In this work, a serie of borate glass of the system (80-x) B₂0₃ –10Na₂O- 10ZnO- x Er₂O₃ (x= 0.5 -1.5 mol %) has been prepared by melt quenched technique. Their optical properties by mean of the UV-VIS-IR and photoluminescence have been identified. From the result, there are 5 significant absorption peaks that corresponds to 487 nm, 750 nm, 820 nm,894 nm and 979 nm wavelength have been observed. Meanwhile there are six significant emission peaks have been observed which corresponds to 401 nm, 434 nm, 481.5 nm, 526 nm, 556 nm and 700 nm wavelength. Thus, from the photoluminescence results, the green, yellow and red spectrum can be expected. Some other results will be analysed and discussed.

Abstract: Electromigration effects on the solder joint formation of 99.3Sn-0.7Cu and 96.5Sn-3.0Ag-0.5Cu lead-free solder with Cu electroplated Ni layer wire were investigated. The electromigration effects on the solder joints were studied after current density stressing at 1 x 10³ A/cm² in room temperature for 0 h, 120 h, and 240 h. The research work found that intermetallic compound (IMC) formation on the joint is increases for both solders with longer period of current stress applied. Higher IMC thickness growth in 99.3Sn-0.7Cu solder joint compared to 99.3Sn-0.7Cu is detected and both anode regions of the solder joints show higher IMC thickness growth compared to cathode region. Experimental results show 99.3Sn-0.7Cu solder joint is more prone to failure under current stress compared to 96.5Sn-3.0Ag-0.5Cu solder joint with thicker IMC which translates to higher brittleness.

Abstract: This paper investigates the stability analysis of plates made of functionally graded material (FGM) and integrated with piezoelectric actuator and sensor at top and bottom face subjected to electrical and mechanical loading. The finite element formulation is presented using degenerated shell element, von-Karman hypothesis, higher-order shear deformation theory and considering the piezoelectric effect. The governing equilibrium equation is derived using the principle of minimum energy and solution for critical buckling load is obtained by solving Eigen value problem. The material properties of the FGM plates are assumed to be graded along the thickness direction according to simple power-law distribution in terms of the volume fraction of the constituents, while the poison’s ratio is assumed to be constant. Stability analysis is carried out on simply supported plate made of newly introduced metal based functionally graded material (FGM) i.e. mixture of aluminum and stainless steel which exhibits the two different material properties in single material i.e. high corrosion resistance as well as high strength. Results show that the buckling strength of plate increases with increase in volume fraction indices through the thickness and it can be further improved with the help of piezoelectric effect.