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In this study, composite materials were made from Carica papaya fibers (CPFs), as a reinforcing element in polypropylene (PP), polyester (P) and epoxy (E) matrices, using compression molding technique. Experiments were conducted to evaluate the input parameters with their output responses, specifically density and thickness. Various CPF reinforced PP, P, and E composite specimens with varied fiber orientations of 0°, 45°, and 90° as well as percentages of fiber contents of 10, 20, and 30 wt.% were prepared, according to the ASTM D 570 standard. From the results obtained, it was observed that CPF/E composites with fewer fraction of CPF and orientation of 90° exhibited less water absorption throughout the whole duration of immersion. Water saturated CPF/E composite specimen, designated as E8, with orientation of 0° and fiber content of 20 wt.% showed the highest tensile, flexural strengths, and Shore D Hardness of 119, 115 MPa, and 85, respectively. Also, CPF/E composite specimen (E7) with 90° and 10 wt.% recorded the lowest tensile strength of 32 MPa, and CPF/E composite (E3) with 90° and 30 wt.% showed the lowest flexural strength of 41 MPa. Hence, it was evident that optimum CPF reinforced polymeric composite can be used for some outdoor engineering applications.

This paper presents a study on extraction and characterization of the cellulose fiber from the bark of Erythrina variegate (EV) plant. Several tests were carried out on Erythrina variegata fibers (EVFs) to determine their properties. These included thermogravimetric analysis (TGA)/difference thermogravimetric (DTG), X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR) as well as morphological analysis, using scanning electron microscopy (SEM) and atomic force microscopy (AFM). From the results obtained, chemical composition of EVFs, such as cellulose, lignin, ash, and wax content of 70.60, 12.70, 8.60, and 0.24 wt.%, respectively, were recorded through standard chemical analysis. The maximum and average tensile strength of the EVFs were found as 6.06 ± 0.02MPa and 2.80 MPa, respectively. The thermogravimetric analysis on the fiber showed excellent stability with a char residue of 19.23% and a maximum degradation temperature of 349°C. The crystallinity index (CI) of 37.5% and crystalline size of 36.93 nm of EVFs were calculated through X-ray diffraction analysis. The morphological study established that EVFs possessed rough surface even in raw form. The density of EVF was obtained at 1412 kg/m3, which was higher than that of Grewia damine of 1378 kg/m3 and lower than that of jute of 1460 kg/m3.

The objective of this paper was investigated to evaluate tensile, flexural and Impact properties of Palm fibre reinforced Epoxy composites (PFRP) and compared with Sisal fibre reinforced Polyester composites (SFRP). Untreated chopped Palmyra Palm fruit fibre was used as reinforcement in Epoxy resin matrix and chopped sisal fibre was used as reinforcement in Polyester resin matrix. The chopped palm fibrereinforced composite were prepared in volume fractions (Vf) such as 10 %, 20 % and 30 % of specimens by using Epoxy and the chopped sisalfibre reinforced composite were prepared in volume fractions (Vf) such as 10 %, 20 % and 30 % of specimens by using Polyester. The specimens are tested for their mechanical Properties strictly as per ASTM procedures. Static analysis is performed by FEA based software ANSYS R15 with design constraints as Equivalent stress, Shear stress and deflection.The experimental result and analysis shows that the fibre volume fraction increases the tensile, flexural, Impact strength and modulus of the fibre reinforced composites

This paper presents the first report of the excellent oxygen reduction activity and durability of a composite structure that consists of highly active V2O5-WO3 electrocatalyst. Outstanding electrocatalytic performance toward oxygen reduction under alkaline medium was achieved by selecting a highly active and optimum concentration of V2O5 on WO3 composite. In particular, the excellent catalytic activity of the 25 wt.% V2O5 with 75 wt.% WO3(WV − 1) catalyst for oxygen reduction reaction (ORR) can be attributed to the optimum concentration of V2O5, high surface area, high conductivity, and mesoporous nature, since they aid facile electrochemical activity and reduced overpotential and small Tafel values than other catalysts. In addition, it exhibits long-term durability. [ABSTRACT FROM AUTHOR]

Magnetic field induced binding energy of two donors in a parabolic GaAs/AlGaAs nano dot is reported. The calculations are carried out using variation ansatz within the single band effective mass approximation. The binding energy is estimated for different inter-impurity distances in the presence of magnetic field. The correlation effect of two donors is introduced through the wave function. It is found that interimpurity distance, correlation of donors and the magnetic field strength make the electron more binding. [ABSTRACT FROM AUTHOR]