Advanced Materials Research Vols. 476-478

Abstract: By using mixture solution method, Barium titanate/polyimide(BT/PI) composite film was prepared. Influence of different size and filling quantity of BT particles were investigated. The microstructure and properties of the products were characterized by scanning electron microscopy, X-ray diffraction and other analysis methods. The results show that when BT nanoparticles are used, the BT/PI film has better comprehensive performance. As the filling quantity of BT particles increases, the dielectric constant and dielectric loss of BT/PI composite film increase, and the dielectric strength is reduced.

Abstract: Sichuan Province faces several development challenges including those linked to climate change. Energy usage in Sichuan Province, for example, is already constrained because of a range of development challenges (energy availability; access; affordability of alternative energy sources; and a range of health impacts, including air pollution). There calls for a transition to a low carbon energy options. Although the major obstacles preventing people from discontinuing domestic traditional biomass fuels or coal combustion are poverty, the ready availability and social acceptability of energy options cannot be underrated. This paper therefore highlights some of the persistent challenges associated with sustainable energy transitions in Sichuan Province. We aim to explore how renewable and low-carbon energies can maintain sustainable rural energy development and partially replace fossil fuels development in rural areas of Sichuan Province and thereby serve as mitigation options is a possible future transition towards a low-carbon system relying on renewable and low-carbon energies.

Abstract: we built the rutile SnO2 to study SnO2 improving gas sensor properties for rutile structure of SnO2 existing in the SnO2-In2O3 composite materials by X-ray analysis. The surface (110) of SnO2 is a stable structure by analysis of surface energy. Compared with oxidized surface (110), reduced surface (110) has better conductivity and stability. As a result, the CO adsorption changes the electric conductivity of the whole reductive (110) surface, and leads to the deviation of Fermi energy. Therefore, it is an important reason affecting gas sensor properties of the SnO2-In2O3 composite materials. By calculating and simulating the density functional first-principal, the research of the adsorption of rutile SnO2 towards CO provides a theoretical foundation for the argument of the gas sensitivity of porous SnO2-In2O3 composite materials towards CO with the increasing of SnO2 contents.

Abstract: This paper adopted XRD, SEM and DTA/TGA methods to discuss the microstructure of sinter AgSnO2 compositions with bismuth and without bismuth. The results showed that microstructures AgSnO2 compositions are different whether or not include bismuth. The introduction of Bi does not produce the expected SnO2 and Bi2O3 phase, but generated SnO2 and Sn2Bi2O7 phase. The reason with different microstructure has relation with early melting of Bi-rich alloys having low melting point and silver oxide decomposition rate and sinter temperature. Therefore, bring third element should be cautious for preparation composite metal oxide increase silver matrix electrical contact materials.

Abstract: In this paper, we present the design of a novel hybrid dielectric-metal-dielectric waveguide, which consists of a metal stripe sandwiched between low-high dielectric layers. Its modal characteristics are investigated using the finite element method at the telecom wavelength. Simulations show that the dielectric contrast near the metal stripe results in a strongly confined hybrid plasmonic mode with sub-micron mode size and low propagation loss. The effects of geometrical parameters are analyzed systematically and the properties of directional couplers based on such hybrid waveguide are also investigated. The proposed structure could be useful candidates for various integrated optical devices and enable many applications such as electro-optic modulation, switching, sensing and more.

Abstract: This paper aims to understand the potential of using wheat straw (WS) as a source for composite. High quality fiber bundles are obtained from wheat straw using a simple alkaline treatment method. Wheat straw fibers (WSFs) are used with PLA fibers to make composites. The effect of sodium hydroxide concentration and temperature of the treatment processes for wheat straw fibers on the tensile and flexural properties of the PLA/WSF composites has been investigated. The contact angle of WSF has also been studied. It shows that the the mechanical properties of PLA/WSF composites are optimal when the sodium hydroxide concentration is 2.5% and the alkali treatment temperature is 125°C. The contact angles after alkali treatment decrease significantly, indicating that the surface wettability of the treated wheat straw is improved.

Abstract: In the present work some characteristical features of autoclaved aerated concrete structures are illustrated in the seismic and nonseismic design for residential and industrial buildings. Besides the properties of this material with regards to fire resistance and thermal and acoustical insulation, the use of autoclaved aerated concrete for engineering structures may have the advantage of a confined structure with reinforced concrete bond elements that are disposed horizontally and vertically. In the present work the dynamical behavior of a building prototype realized with autoclaved aerated concrete is analyzed, a finite element modelling of the structure has been calibrated according to an experimental modal analysis carried by loading the structure with a vibrodyne located on top of the building and by monitoring the building outputs due to horizontal harmonic forces. The finite element modelling of the dynamical behavior of the autoclaved aerated concrete structure has been compared with a similar tuff masonry building whose characteristical behavior has already been the object of experimental and numerical analysis in a previous work.

Abstract: It is well known that the interface between the particle and matrix of the composite was significantly important as it could control the load transfer between the matrix and filler of composite. Despite of, in the polymer nanocomposites, the role of interface is still fragmented and less examined. In this paper, two different designs of interface modification were developed; molecular entanglement and chemical reaction using three variants surfactants such as ethanolamine, Jeffamine M2070 and Jeffamine XTJ502, with further investigation of structure-property relationship of epoxy/clay nanocomposites. The nanocomposites were prepared via solution mixing by reinforced 1.0–4.0 wt% of treated-clay. The interface properties were then characterized by XRD, FTIR, tensile test and fracture toughness. Results showed that for the epoxy/clay synthesized by reactive surfactant demonstrated higher stiffness and enhanced fracture toughness.

Abstract: A novel composites material consisting of calcium silicate deposited in bacterial cellulose membrane was synthesized by immersing BC membrane in the calcium and silicate solutions by turns with different cycle times and characterized. The results indicated that the CaSiO3 particles were homogeneously dispersed on the surface of nanofibers with the effect of BC template when two cycles of soaking proceed, during which the fabrication of most CaSiO3 particles took place. The FT-IR reveals the strong interaction between the two parts of the BC/CaSiO3 composite. The XRD pattern demonstrated a crystal structure disruption of the cellulose aroused by CaSiO3 particle. BC/ CaSiO3 is considered to have a potential application in bone tissue field.

Abstract: It is precondition for realizing the mechanical dynamic optimization design and the dynamic modification to analyze the characteristic of multi-degree-of-freedom system. The paper discusses a kind of modal parameters wavelet transform identification method based on Modified Particle Swarm Optimization (PSO) algorithm, furthermore, proposes the PSO wavelet ridge extraction algorithm, and gives the formulas identifying modal parameters from a wavelet ridge. The proposed method applies to the dynamic characteristic identification of a flow meter to explore the effectiveness. The results prove the method is precision and insensitive to noise.