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In the present investigation, cordia-dichotma fiber was used as reinforcement for the development of natural fiber composite. The novelty of this research work lies in the investigations of basic mechanical, thermal and structural properties of raw cordia-dichotoma fiber reinforced epoxy composites. Cordia-dichotoma fiber reinforced composites were prepared using the hand-layup technique with different weight proportions (10, 15, 20, and 25) of fiber into the epoxy resin. The composites were tested to evaluate the mechanical properties using Universal Testing Machine (UTM). From the results, it is clear that the mechanical properties increase up to 20% weight of the fibers and later decreases due to the improper bonding between the fibers and the epoxy. Further, for an inclusive materialcharacterization, the presence of chemical compounds and functional groups were identified by FTIR spectroscopy. SEM analysis was used to observe bonding between fibers and epoxy, and also the thermal stability of the composite specimen was observed through Thermo-gravimetric Analysis (TGA). The performance of these composites leads to potential use of outdoor, infrastructure and structural applications with low cost and practical processing methods.

In recent days, use of fiber reinforced polymer composites is growing rapidly due to their better mechanical properties like tensile strength, flexural strength, and impact strength; and also due to their low cost and low density. In the present work, Burmese silk orchid fibers are used as reinforcement and epoxy as matrix material to fabricate the composite material. Using hand-layup technique, composite specimens were prepared by increasing the weight of the fibers as 5, 10, 15, and 20 grams. Test specimens are cut as per the ASTM standards. Tensile strength, flexural strengths are determined using Instran Universal Testing Machine and impact strength of the samples is measured using Izod impact testing machine. Experimental results are validated.

Environmental and societal concerns such as pollution, disposal of solid waste, requirement of different conflicting properties for materials in varied applications and cost are the main reasons for the development of new materials from the existing materials. The concerns may possibly be overcome by substituting natural fibers for synthetic fibers. In this study, a hybrid composite was developed by reinforcing the natural fiber “cordia dichotoma” and filler “granite powder” into polyester resin. This composite was fabricated using hand lay-up method. Cordia dichotoma fibers were surface treated with NaOH for reducing the hydrophilic nature of the fiber. Unused industrial waste in the form of granite powder obtained from the granite polishing industry is utilized as reinforcement in polymer composite. The hybrid composite was prepared by reinforcing a constant cordia dichotoma fiber content of 20 wt % and varying the granite powder weight (wt. %) percentages (0, 5, 10, 15, and 20) into polyester resin. Mechanical properties (tensile, flexural and impact) of hybrid composites were investigated. The novelty of this work lies in utilization of granite powder sourced from industrial waste utilized as filler material. Granite, as one of the hard materials, may improve wear and other mechanical properties. Following the results obtained, granite powder could be evidenced as a good filler material for the betterment of composites mechanical properties. Also, the ability of this filler material is proved in decreasing water absorption and chemical resistance. Scanning electron microscope (SEM) analysis was performed to investigate the bonding and distribution of granite powder within both the fiber as well as resin in the composite. Besides, the presence of chemical functional groups in the composite was traced by Fourier transform Infrared spectroscopy (FTIR). Also, Thermo-gravimetric analysis (TGA) was carried out and the composite was found to be thermally stable up to 415 °C.

Potentiometric equilibrium measurements have been made at 35°C for the interaction of 5′-cytidine monophosphate and Cu(II), Ni(II), Zn(II), Co(II), Mn(II), Mg(II) and Ca(II) with biologically important secondary ligands (glycine, oxalic cid, histidine and histamine) in a 1:1:1 ratio. Similar studies with cytosine were carried out for comparison. For the above systems, the ternary complexes are found to be more stable than the corresponding binary complexes. The Δ log K values for 1 : 1 : 1 complexes of metal-5′-cytidine monophosphate (or cytosine) with aromatic ligands are more positive compared to the corresponding complexes with aliphatic ligands. This is explained in terms of “stacking phenomenon” that occur between the two aromatic moieties of the primary and secondary ligands in solution.