Jute and bamboo fiber-reinforced polypropylene (PP) based composites (50 wt% fiber) were fabricated by compression molding. Tensile strength (TS), bending strength (BS), tensile modulus (TM), and bending modulus (BM) of the jutereinforced PP composite were found to be 48, 56, 900, and 1500 MPa, respectively. Then, bamboo fiber-reinforced PP-based composites (50 wt% fiber) were fabricated and the mechanical properties evaluated. The TS, BS, TM, and BM of bambooreinforced PP composites were found to be 60, 76, 4210, and 6210 MPa, respectively. It was revealed that bamboo fiber-based composites had higher TS, BS, TM, and BM compared to jute-based composites. Degradation tests of the composites (jute fiber/PP and bamboo fiber/PP) were performed in soil at ambient conditions for up to 24 weeks. It was revealed that bamboo fiber/PP composite retained its original mechanical properties higher than that of jute fiber/PP composite. The interfacial shear strength of the jute and bamboo fiber-based composites was investigated using the single-fiber fragmentation test and it was found to be 2.14 and 4.91 MPa, respectively. Fracture sides of the composites were studied by scanning electron microscope, and the results revealed poor fiber matrix adhesion for jute fiber-based composites compared to that of the bamboo fiber-based composites. Journal of THERMOPLASTIC COMPOSITE MATERIALS,

In this investigation, well defined mesoporous zirconia nanoparticles (ZrO2 NPs) with cubic, tetragonal or monoclinic pure phase were synthesized via thermal recovery (in air) from chitosan (CS)- or polyvinyl alcohol (PVA)-ZrOx hybrid films, prepared using sol–gel processing. This facile preparative method was found to lead to an almost quantitative recovery of the ZrOx content of the film in the form of ZrO2 NPs. Impacts of the thermal recovery temperature (450, 800 and 1100 °C) and polymer type (natural bio-waste CS or synthetic PVA) used in fabricating the organic/inorganic hybrid films on bulk and surface characteristics of the recovered NPs were probed by means of X-ray diffractometry and photoelectron spectroscopy, FT-IR and Laser Raman spectroscopy, transmission electron and atomic force microscopy, and N2 sorptiometry. Results obtained showed that the method applied facilates control over the size (6–30 nm) and shape (from loose cubes to agglomerates) of the recovered NPs and, hence, the bulk crystalline phase composition and the surface area (144–52 m2/g) and mesopore size (23–10 nm) and volume (0.31–0.11 cm3/g) of the resulting zirconias.

Drought is a major abiotic stress that adversely affects the rice growth, mostly in the rainfed ecosystem that ultimately affects the biomass production and yield. Rice needs to adapt a series of physiological mechanisms with complicated regulatory network to fight and cope up with the unfavourable conditions due to drought stress. Morphological and physiological response in rice include inhibition of seed germination, slower growth rate, low root and shoot length, lower chlorophyll content, stomatal closure, lower rate of photosynthesis, yield reduction etc. Stress condition further results in development of response at the molecular level by the generation of reactive oxygen species (ROS) such as O2*-, H2O2, 1O2, OH* etc. which incites oxidative stress in the plants. Oxidative stress is overcome by the inherent capacity of plants to produce antioxidant species which may be enzymatic or non-enzymatic in nature. If however antioxidant defence mechanism cannot overpower the ROS generated, they cause oxidative damage to the plant tissues such as lipid peroxidation, protein oxidation, DNA damage, etc. resulting in cell death. Unlike other stresses, drought affects the physiology and biochemistry of the rice which adversely affects in the morphology and consequently delimits the yield of the plant. Therefore, understanding the morphological, biochemical and molecular mechanisms involved in rice against drought is utmost necessary for rice breeders to improve the rice for drought tolerant/resistance varieties for future green revolution. In this review, an attempt has been made to highlight the complex regulatory network involved in rice against drought with special emphasis on morphological, physiological and molecular mechanisms and to discuss the prospective and challenges for future plant breeders.

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