Synthesis, Characterization and Biological Activity of Oxovanadium(IV) Complexes Containing α-Amino Acid Schiff Bases and 5,6-Dimethyl-1,10-phenanthroline Ligands

Five oxovanadium(IV) complexes of the type [VO(L)(DPhen)], containing Schiff base derived from α-amino acid, [where L = 3-hydroxybenzaldehyde-α-alanine (hb-Ala), 3-hydroxybenzaldehyde-DL-phenylalanine (hb-Phe), 3-hydroxybenzaldehyde-leucine (hb-Leu), 3-hydroxybenzaldehyde-glycine (hb-Gly) and 3-hydroxybenzaldehyde-DL-methionine (hb-Met) & DPhen = 5,6-Dimethyl-1,10-phenanthroline] have been synthesized and characterized by some physicochemical properties, molar conductance, magnetic susceptibilities measurements, elemental analysis, UV-Visible, FT-IR and EIS-MS spectral studies. The molar conductance values evidenced the non-electrolytic nature of the complexes. The magnetic moment values of the complexes are in accordance with the d1 electronic configuration of the VIVO2+ moiety and indicates the paramagnetic behavior of the complexes. IR spectral data indicates the coordination of tridentate amino acid Schiff base ligands to the vanadyl (VO2+) ion through O, N, O-donor. ESI-MS spectral study confirmed the proposed structure of the complexes. All the analytical data suggested that all the complexes possess to have distorted octahedral geometry. The complexes were screened for their antibacterial activity against four human pathogenic bacteria; two Gram positive Escherichia coli & Pseudomonas aeruginosa and two Gram negative Staphylococcus aureus & Bacillus cereus with Kanamycin (K-30) standard. The result shows that all the complexes have moderate to strong potential antibacterial activity against all the pathogenic bacteria. This work is licensed under a Creative Commons Attribution 4.0 International License

Synthesis of Cotton from Tossa Jute Fiber and Comparison with Original Cotton

Cotton fibers were synthesized from tossa jute and characteristics were compared with original cotton by using FTIR and TGA. The FTIR results indicated that the peak intensity of OH group from jute cotton fibers occurred at 3336 cm−1 whereas the peak intensity of original cotton fibers occurred at 3338 cm−1. This indicated that the synthesized cotton fiber properties were very similar to the original cotton fibers. The TGA result showed that maximum rate of mass loss, the onset of decomposition, end of decomposition, and activation energy of synthesized cotton were higher than original cotton. The activation energy of jute cotton fibers was higher than the original cotton fibers

Effect of silicon dioxide/nanoclay on the properties of jute fiber/polyethylene biocomposites

In this study, (jute fiber)/polyethylene biocomposites were prepared by using a hot press machine. Jute fiber was investigated as a reinforcing filler material for producing structural composites with better environmental performance. The effects of clay and silica addition on the physical, mechanical, and thermal properties of (jute fiber)-reinforced polyethylene biocomposites with different fiber loadings (5, 10, 15, and 20 wt%) were investigated. The biocomposites were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The composite surface area and pore volume were determined by using the Brunauer-Emmett-Teller equation. The mechanical properties were investigated by using a Universal Testing Machine. Because of Si-O-Si stretching vibration, the O-H group from 3,200 to 3,400 cm−1 disappeared. The scanning electron microscopy results proved that a significant difference among the composites was present due to the interfacial bonding between the fiber and the matrix

Improved thermal properties of jute fiber-reinforced polyethylene nanocomposites

The thermal behavior of chemically modified jute fiber-reinforced polyethylene (PE) nanocomposites was investigated. Nanocomposites were prepared by hot press molding technique using different fiber loadings (5, 10, 15, and 20 wt%) for both treated and untreated fibers. Jute fibers were chemically modified with benzene diazonium salt to increase their compatibility with the PE matrix. Surface and thermal properties were subsequently characterized. Fourier transform infrared spectroscopy and scanning electron microscopy analysis were used to study the surface morphology. Thermogravimetric analysis (TGA) and differential scanning calorimetry were carried out for thermal characterization. Fourier transform infrared spectroscopy and scanning electron microscopy study showed interfacial interaction among jute fiber, PE, and nanoclay. It was observed that, at optimum fiber content (15 wt%), treated jute fiber-reinforced composites showed better thermal properties compared with that of untreated ones and also that nanoclay-incorporated composites showed enhanced higher thermal properties compared with those without nanoclay. POLYM. COMPOS., 38:1266–1272, 2017. © 2015 Society of Plastics Engineers. © 2015 Society of Plastics Engineer

Characterization of chemically treated jute fiber reinforced polyethylene clay nanocomposites as a function of treatment methods

The hydrophilic nature of natural fibers unfavorably affects adhesion with a hydrophobic matrix which cause loss of strength. In order to reduce hydrophilicity and remove non cellulosic constituents to enhance the interfacial interaction with the polymer matrices, the jute fibers (Corchorus olitorius) were chemically treated with benzenediazonium salt (BDS), propionic anhydride (PA), and 3-isocyanatopropyltriethoxy silane. Jute fibers (raw and treated), polyethylene (PE) granules and different types of montmorillonites (MMT) were mixed thoroughly in different weight fractions for the manufacturing of nanocomposites. The effect of chemical treatments and montmorillonite addition on the improvement of different properties of silane treated jute fiber reinforced polyethylene/clay nanocomposites have been investigated. Tensile tests (tensile strength and tensile modulus), fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) analysis, water absorption, and chemical absorption test were used to evaluate the mechanical, microstructural, and physico-chemical absorption characterizations of the prepared composites. It has been observed that the optimum fiber loading was 15 wt.%. Treated jute composites showed higher improvement in all of the mentioned properties than raw jute composite and silane treated jute composite found highest improvement. Nanoclay loaded composites showed higher improvement than composite without nanocJay and 2 wt.% MMT nanoclay loaded nanocomposites showed highest values in different properties. On the other hand, MMT-1.3IPS nanoclay loaded nanocomposite exhibited highest improvement among five types of MMT nanoclay loaded nanocomposites used in this study. The fabricated nanocomposites were resistant to all chemicals used except carbon tetrachloride (CCl.). All the mentioned properties of the nanocomposites were improved due to chemical treatment of fibers and further addition of nanoclay

Review on the Risk Assessment of Heavy Metals in Malaysian Clams

The current review discusses the levels of six heavy metals in different clam species from 34 sites of Malaysian coasts. The concentrations (µg/g dry weight) of these heavy metals ranged around 0.18–8.51, 0.13–17.20, 2.17–7.80, 0.84–36.00, 24.13–368.00, and 177.82–1912.00 for Cd, Pb, Ni, Cu, Zn, and Fe, respectively. It was observed that the concentrations of metals slightly depend on different clam species but mostly depend on site locations. According to Malaysian Food Regulation (1985), about 30% and more than 50% sites are safe from Cd and Pb contamination, respectively, and also the clam species from the other populations studied were safe for consumption

Investigation of the Acoustic Properties of Chemically Impregnated Kayu Malam Wood Used for Musical Instrument

The chemical modification or impregnation through preparing the wood polymer composites (WPCs) can effectively reduce the hygroscopicity as well as can improve the acoustic properties of wood. On the other hand, a small amount of nanoclay into the chemical mixture can further improve the different properties of the WPCs through the preparation of wood polymer nanocomposites (WPNCs). Kayu Malam wood species with styrene (St), vinyl acetate (VA), and montmorillonite (MMT) nanoclay were used for the preparation of WPNCs. The acoustic properties such as specific dynamic Young’s modulus (Ed/γ), internal friction (Q−1), and acoustic conversion efficiency (ACE) of wood were examined using free-free flexural vibration. It was observed that the chemically impregnated wood composite showed a higher value of Ed/γ than raw wood and the nanoclay-loaded wood nanocomposite showed the highest value. The reverse trend was observed in the case of Q−1. On the other hand, chemical impregnation has a minor effect on ACE of wood for musical instruments. The results suggested that the chemically impregnated Kayu Malam wood polymer nanocomposite (WPNC) is suitable for making soundboards of violin and guitar instruments to be played longer without losing tone quality