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In present research the fracture behavior of carbon fabric‐epoxy composites (CE composites) was evaluated with the addition of 0.1, 0.2, 0.5, and 0.75 weight percentages of carbon nano tubes (CNTs) at different temperatures. The CE composites with different wt.% of CNT were fabricated using land layup method and cured by hot pressing. The fracture toughness of fabricated composites was evaluated in mode–I condition at different temperature. From the results it was shown that the highest fracture toughness was observed at 0.75 wt.% of reinforcement of CNT functional fillers. The fracture toughness of 0.75 wt.% CNT filled CE composites was increased by 19.73% compared to unfilled CE composites. The fracture toughness of CNT filled CE composites diminishes with increase in temperature and the composite filled with 0.75 wt.% CNT exhibits better fracture toughness than the unfilled CE composite at all the temperatures. The fracture toughness was improved by 57.76% and 71.65% at 40 and 60°C, respectively, at 0.75 wt.% reinforcement of CNT fillers. The fractured surfaces of composites were analyzed using Scanning Electron Microscope (SEM) to study the filler contribution to enhance the fracture toughness and failure mechanism of composites. [ABSTRACT FROM AUTHOR]

The addition of fillers to polymer composites induces a positive influence on the mechanical and tribological properties of the hybrid composites. These properties can be validated for possible uses such as automobile, construction, shipping, aerospace, sports equipment, electronics, and biomedical domains. In the present research, epoxy matrix reinforced with nylon-6 fibers and glass fibers were prepared using the solution blend technique. Alumina nanoparticles are added as fillers to enhance the properties of epoxy hybrid composites. The large surface area of interaction of nanofillers exhibits better adhesion between matrix and fibers of composites, and it significantly affects the various properties of composites. The tribological characteristics of fabricated epoxy hybrid composites were evaluated under various parameters and conditions. The results revealed that the addition of nanofiller significantly reduces the wear loss of epoxy hybrid nanocomposites. The wear resistance of epoxy hybrid composites increased with increase in addition of nanofiller up to 1.0%, and it slightly decreased with the further addition of filler. The Taguchi analysis was carried out for the least coefficient of friction and specific wear rate. The analysis found that the specific wear rate and coefficient of friction mainly depend on load, followed by speed and nanofiller. The fractured and worn surface of Al2O3-filled epoxy hybrid composites was analysed using SEM. [ABSTRACT FROM AUTHOR]

Psychrophilic and psychrotolerant bacteria have evolved various strategies to adapt to low temperature. One important strategy, which is crucial to the survival of the cell at low temperature, relates to the ability of the cell to modulate the fluidity of the membrane. Bacteria in general modulate membrane fluidity by altering their fatty acid composition. But, bacteria could also achieve the same by various other strategies such as by altering the lipid head group, the protein content of the membrane, the type of carotenoids synthesized, the fatty acid chain length and the proportion of cis to trans fatty acids. In addition bacteria have a two-component signal transduction pathway consisting of a membrane-bound sensor and a soluble cytoplasmic response regulator involved in the perception and transduction of low temperature signals. This review on cold adaptation highlights the various strategies by which bacteria modulate the fluidity of the membrane and the process by which it senses and transduces the low temperature signal.