Jute and banana fibers are biodegradable green fibers being increasingly used to replace synthetic fibers in fiber-reinforced polymer composites. Integration of jute and banana distinct natural fibers has the potential to improve composite performance in secondary structural applications. In this study, an equal quantity of unidirectional jute and banana fibers with four different fiber orientations [(0/0) 3s , (0/45) 3s , (0/90) 3s , and (+45/À45) 3s ] was embedded in phenol formaldehyde resin to make hybrid laminates using the hot press method. Tensile, flexural, impact, interlaminar shear strength (ILSS), and single-end notch bend tests are performed in accordance with the ASTM standards to evaluate the effect of fiber orientation on natural fiber hybrid composites (NFHCs).Experimental results revealed that changing the fiber orientations [(0/0) 3s ] leads to a major impact on reducing the mechanical properties of NFHC laminates to the extent of 39%. Furthermore, the tensile strength, Young's modulus, impact and ILSSs, and fracture toughness were found to be 37% higher for the (0 /0 ) 3s composite. Additionally, tensile, flexural, and impact fractured specimens were examined by scanning electron microscopy to understand the fiber-matrix failure behavior due to inter-ply orientation in NFHCs.

In the high altitude areas of western Himalaya, barley is a crop of marginal, low input drought stressed environments. The landraces grown in these areas are favoured for their quality, both as grain and straw. However, area under the naked barley landraces, during the last three to four decades, has declined considerably and their ex situ and in situ conservation requires attention. Morphological and RAPD descriptors of a collection of 70 landraces from the higher Himalayan ranges of Uttaranchal state were used to analyse levels of genetic diversity. A wide range of variation was recorded for various morphological characters in univariate analysis. The multivariate analysis based on six quantitative traits distinguished accessions from different geographical areas in the region but failed to separate naked from covered barleys. Clustering based on qualitative traits, however, clearly distinguished naked and covered forms. RAPD profiles efficiently differentiated naked barleys from covered forms, but could not differentiate between oriental and occidental covered forms. A set of 11 predominant landraces were subjected to detailed population genetic analysis. More diversity was observed in covered barleys than the naked forms, both for morphological and RAPD markers. The low diversity in naked barley populations was attributed to either genetic drift or to a founder effect, while the high diversity in covered barley populations was attributed to their large-scale cultivation for animal feed and brewing purposes. Allelic combinations were not randomly distributed, as a geographic trend was closely related to covered and naked barleys. Since naked barleys are poorly represented in the national collections, a systematic collection from the entire region is suggested. The genetic differences between covered and naked barleys may be relevant to breeding programmes since the variability created through hybridisation between the contrasting forms could be exploited.

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The primary purpose of this study is to realize quantitative fiber loading effects on free vibration, damping behavior, fracture toughness, thermal conductivity, inter-laminar shear strength, and flammability of jute-banana fiber phenolformaldehyde (PF) hybrid composites. These composites were manufactured with fiber weight percentages ranging from 30% to 60% using hot press technique. Hybrid composite with equal amount of fiber and resin (PJB-2) had a higher natural frequency in the range of 4.8%-59%, a higher inter-laminar shear strength varying from 30% to 54%, a higher fracture toughness with minimum of 19 to maximum of 44%, and a low damping factor in the range of 25%-59% to that of other composite having unequal amount of fiber and resin loading. In contrast to other composites, the composite containing 30 wt% fiber (PJB-4) has a high heat conductivity of about 10%-20%. However, the thermal conductivity of jute-banana fiber PF composites declined as the fiber content increased beyond 30 wt%, while the flame resistance was improved as the resin concentration increased. Additionally, Scanning electron microscopy (SEM) studies clearly indicates the failure patterns of fiber matrix interface under Inter laminar shear strength and fracture toughness tests were supports to justify the experimental results.