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In this paper, cross-plane thermal conductivities of the nanoporous glass alumina film (NGAF) and its composites (Ag/NGAF, with Ag nanowires embedded in) were measured. And a model was setup to predict the thermal conductivity of the nanoporous material. Results show that the thermal conductivity of the NGAF is about 50 times smaller than that of the ceramic alumina. It is about 0.5 W ⋅ m^-1⋅ K^-1 and depends on both the pore radius and the porosity. The thermal conductivity of the Ag/NGAF is not larger than that of the NGAF. The contact resistance and the unfilled space between Ag nanowires and the matrix are responsible for that.

With the improvements in quality of life and better awareness about the requirement for a secure environment, fire-resistant materials have gradually attracted the world’s attention and recognition. This paper investigates a proprietary process to manufacture glass fiber (GF) reinforced brominated-epoxy (BEP) flame retardant composites through pultrusion. BEP resin is manufactured with fillers as matrices, GF as reinforcements for pultrusion. The dynamic mechanical properties (DMA) and flame retardant properties of the GF reinforced BEP composites manufactured through pultrusion have been investigated. The DMA test showed higher dynamic storage modulus $(E^{\prime })$ and lower curve of tan $\delta$ of pultruded composites when the filler content, postcure temperature and postcure time increased. At the same time, the glass transition temperature $(T_g)$ of the pultruded composites were shifted to a higher temperature when the filler content, postcure temperature and postcure time increased. From the flame retardant test for UL-94 and limited oxygen index (LOI), all of the pultruded GF reinforced BEP composites as well as the BEP resin showed excellent flame retardant properties.

A strategy for continuous fabrication of a microscale 3D-patterned hybrid composite film composed of alumina and acrylate resin was developed using roll-to-roll production. Conventional thermal curing was replaced with a UV curing procedure to facilitate rapid and economical processing. A seamless engraved soft urethane mold was first produced using a patterned metal roll. Subsequently, alumina and acrylate resin were cured on the engraved mold via UV irradiation to produce patterned hybrid films. The dispersion of alumina particles in acylate resin was enhanced by utilizing amine acrylate. Photopolymerization was measured using Fourier-transform infrared spectroscopy. The morphology of the soft engraved mold and the patterned hybrid film was investigated using scanning electron microscopy.

In this study, a three-point bending test was carried out to determine the mechanical properties of hexagonal-shaped honeycomb core sandwich panels made of jute yarn with two distinct fiber orientations. A custom-made handloom was used to weave the unidirectional jute mat, and hand-layup with the cold press process was applied to fabricate the hexagonal honeycomb sandwich panel. To explore the effectiveness of different natural fibers for producing honeycomb core sandwich panels, a Finite Element Method (FEM) analysis was performed on different natural fibers with different fiber orientations. The resistance to environmental deterioration of bending properties was also investigated. Overall, this work offers perceptive information about the mechanical characteristics of sandwich panels made of jute honeycomb core and their behavior under various climatic circumstances, which may be relevant in a variety of engineering applications. Finally, it is noteworthy that the mechanical properties of jute fibers are anisotropic, which implies that their strength varies with the direction of loading. Sandwich panels with horizontal fiber orientation of hexagonal honeycomb core withstand a 36% higher bending strength than those with vertical fiber orientation.

The paper deals with Dielectric Behaviour, Complex Impedance Spectroscopy and Magnetoelectric effect in La_0.7Sr_0.3MnO₃(LSMO) and BaTiO₃ (BT) Composites. The LSMO and BT are synthesized by hydroxide co-precipitation route. The nanocomposites are prepared by two series x LSMO + (1-x) BT + 2 wt % Bi₂O₃, for x = 0.05, 0.1, 0.15 and 0.2 ……series 1. x LSMO + (1-x) BT + 3 wt % Bi₂O₃, for x = 0.05, 0.1, 0.15 and 0.2 ……series 2. and sintered at T_s=1000°C and 1080°C. The composites are termed as LSMO-BT. The paper reports the crystal structure, micro-structural analysis, dielectric constant, complex impedance spectroscopy and magnetoelectric properties of LSMO-BT composites. It has been observed that the ε_r passes through a broad maximum at T ~ 124° C, which is nearly the ferroelectric transition temperature of BT. Both ε_r and ε_rmax increases as x increases from 0.05 to 0.2. The ε_r' and ε_r'' decreases sharply for all the compositions at low frequencies. This feature is typical of the presence of interfacial polarization. The variation of 4πMs is almost linear with x, the 4πMs increases with x as well as sintering aid. The 4πMs of respective compositions reduce as the sintering temperature is increased. The value of α increases for increase in sintering temperature as well as increase in wt % of the sintering aid. The magnitude of α is in the range as reported earlier for composites based on BT.

This paper deals with the adhesion strength of laminated bamboo composites fabricated only from steam-exploded bamboo plates by using a hot-pressing method. The adhesion strength of laminated bamboo composites were evaluated by a short beam bending teats. The effects of molding conditions on the shear strength were examined by changing the molding temperature, time, and pressure. The optimum molding conditions of the laminated bamboo composites are 140°C, 30 min. and 10 MPa among the conditions investigated. The maximum shear strength of the laminated bamboo composites was approximately 46 MPa, and this value is comparable to that of single plate bamboo composites without lamination.