Effect vapor grown carbon nanofiber on thermal and mechanical properties of epoxy

In the present investigation, dynamic mechanical analysis (DMA), thermo gravimetric analysis (TGA), tensile tests, fatigue tests and the single edge notch tensile (SENT) tests were performed on unfilled, 1, 2 and 3 wt.% vapor grown carbon nanofiber (CNF) filled SC-15 epoxy to identify the loading effect on thermal and mechanical properties of the composites. DMA studies revealed that filling the 3% carbon nanofiber into epoxy can produce 65% enhancement in storage modulus at room temperature and 6 °C increase in T _g. However, TGA results show that thermal stability of composite is insensitive to the CNF content. Tensile tests were carried out at the strain rate range from 0.02 min⁻¹ to 2 min⁻¹. Results show that CNF/epoxy are strain rate sensitive materials, the modulus and tensile strength increased with increasing of strain rate. Experimental results also indicate that modulus of the nanophased epoxy increases continuously with increasing CNF content. But the 2% CNF infusion system exhibit maximum enhancement in tensile strength, fatigue performance and fracture toughness as compared with other system.     

A Review on Polymeric Nanocomposites of Nanodiamond,Carbon Nanotube,and Nanobifiller: Structure,Preparation and Properties

In this review, an overview of various types of nanofillers is presented with special emphasis on structure, synthesis and properties of carbon nanotube, nanodiamond, and nanobifiller of carbon nanotube/nanodiamond, carbon nanotube/graphene oxide and carbon nanotube/graphene. In addition, polymer/carbon nanotube, polymer/nanodiamond, and polymer/nanobifiller composites have been discussed. The efficacy of different fabrication techniques for nanocomposites (solution casting, in-situ, and melt blending method) and their properties were also discussed in detail. Finally, we have summarized the challenges and future prospects of polymer nanocomposites reinforced with carbon nanofillers hoping to facilitate progress in the emerging area of nanobifiller technology.     

IP address allocation protocols in vehicular ad hoc networks

In vehicular ad hoc networks (VANETs), communication takes place between vehicles to vehicles, the vehicles to the road side units, and vice-versa. The basic purpose of these communications is to share and exchange tremendous amount of data and information. For efficient information sharing, a systematic and structured connection establishment algorithm is needed. In VANETs, each connected node of the network need to be assigned a unique address. Hence, an algorithm is needed for the proper assignment of unique address to all nodes in the network. This paper explains different types of IP address protocols in VANETs. We have also explained advantage and disadvantage of existing IP address allocation protocols in VANETs.     

Synthesis,characterization and charge transport properties of Pr–Ni Co-doped SrFe2O4 spinel for high frequency devices applications

Ferrites are materials of interest due to their broad applications in high technological devices and a lot of research has been focused to synthesize new ferrites. In this regard, an effort has been devoted to synthesize spinel Pr–Ni co-substituted strontium ferrites with a nominal formula of Sr_1-xPr_xFe_2-yNi_yO₄ (0.0 ≤ x ≤ 0.1, 0.0 ≤ y ≤ 1.0). The cubic structure of pure and Pr–Ni co-substituted strontium ferrite samples calcinated at 1073 K for 3 h has been confirmed through X-ray diffraction (XRD). Average sizes of crystallites (18–25 nm) have been estimated from XRD analysis and nanometer particle sizes of synthesized ferrites have been further verified by scanning electron microscopy (SEM). SEM results have also shown that particles are mostly agglomerated and all the samples possess porosity. It has been observed that at 298 K, the values of resistivity (ρ) increase, while that of AC conductivity, dielectric loss, and dielectric constants decrease with increasing amounts of Pr³⁺ and Ni²⁺ ions. The values of dielectric parameters initially decrease with frequency and later become constant and can be explained on the basis of dielectric polarization. Electrochemical impedance spectroscopy (EIS) studies show that the charge transport phenomenon in ferrite materials is mainly controlled via grain boundaries. Overall, synthesized ferrite materials own enhanced resistivity values in the range of 1.38 × 10⁹–1.94 × 10⁹ Ω cm and minimum dielectric losses, which makes them suitable candidates for high frequency devices applications.     

Effects of repeated frying on physicochemical characteristics,oxidative stress,and free radical scavenging potential of canola oil and ghee

The repeated use of cooking oils and ghee for the deep frying of food materials may affect their nutritional quality. The present study evaluated the effect of repeated frying on the physicochemical characteristics and antiradical potential of canola oil and ghee. The oil and ghee were used for frying of fish and chicken for 2, 4, 6, 8, and 10 frying cycles followed by the analysis of physicochemical, oxidative stress, and antiradical parameters. Regression analysis of the data showed a frying cycle-dependent significant linear increase in saponification (R² = 0.9507–0.9748), peroxide and acid values (R² = 0.956–0.9915), and malondialdehyde (MDA) production (R² = 0.9058–0.9557) of canola oil and ghee subjected to fish and chicken frying but exponential increase in saponification value (R² = 0.9778) and MDA production (R² = 0.7407) of canola oil and ghee used for fish frying. The increase in the number of frying cycles linearly decreased the iodine value (R² = 0.9781–0.9924), and 1, 1-diphenyl-2-picrylhydrazyl, hydroxyl, and 2, 2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical scavenging potential (R² = 0.9089–0.9979) of canola oil and ghee. Repeated frying in cooking oil and ghee increases oxidative stress and decreases their physicochemical and antioxidant qualities. Canola oil was comparatively more oxidative resistant than canola ghee. The regression equations derived from regression analysis will guide researchers to conduct similar types of univariate studies.     

Determination of lithium isotopic composition by thermal ionization mass spectrometry

A mass spectrometric method has been proposed for the determination of the isotopic composition of lithium. It is based upon thermal ionization of LiOH loaded onto a single SiO2-coated Re filament. By this method, stable emissions of Li+ ion have been achieved for an extended period of time. The proposed method is capable of analyzing trace quantities (approximately 40 ng) of Li in the presence of sodium with an uncertainty of +/-0.000 25 (two standard deviations of the mean).     

Green synthesised zinc oxide nanostructures through Periploca aphylla extract shows tremendous antibacterial potential against multidrug resistant pathogens

To grapple with multidrug resistant bacterial infections, implementations of antibacterial nanomedicines have gained prime attention of the researchers across the globe. Nowadays, zinc oxide (ZnO) at nano‐scale has emerged as a promising antibacterial therapeutic agent. Keeping this in view, ZnO nanostructures (ZnO‐NS) have been synthesised through reduction by P. aphylla aqueous extract without the utilisation of any acid or base. Structural examinations via scanning electron microscopy (SEM) and X‐ray diffraction have revealed pure phase morphology with highly homogenised average particle size of 18 nm. SEM findings were further supplemented by transmission electron microscopy examinations. The characteristic Zn–O peak has been observed around 363 nm using ultra‐violet–visible spectroscopy. Fourier‐transform infrared spectroscopy examination has also confirmed the formation of ZnO‐NS through detection of Zn–O bond vibration frequencies. To check the superior antibacterial activity of ZnO‐NS, the authors'' team has performed disc diffusion assay and colony forming unit testing against multidrug resistant E. coli, S. marcescens and E. cloacae. Furthermore, protein kinase inhibition assay and cytotoxicity examinations have revealed that green fabricated ZnO‐NS are non‐hazardous, economical, environmental friendly and possess tremendous potential to treat lethal infections caused by multidrug resistant pathogens.Inspec keywords: nanomedicine, zinc compounds, II‐VI semiconductors, wide band gap semiconductors, nanoparticles, scanning electron microscopy, X‐ray diffraction, antibacterial activity, transmission electron microscopy, particle size, Fourier transform infrared spectra, ultraviolet spectra, visible spectra, enzymes, biochemistry, molecular biophysics, microorganisms, drugs, toxicology, bonds (chemical), semiconductor growth, nanofabrication, vibrational modesOther keywords: green synthesised zinc oxide nanostructures, Periploca aphylla extract, antibacterial potential, multidrug resistant pathogens, multidrug resistant bacterial infections, antibacterial nanomedicines, P. aphylla aqueous extract, structural examinations, scanning electron microscopy, X‐ray diffraction, pure phase morphology, homogenised average particle size, SEM, transmission electron microscopy, Fourier‐transform infrared spectroscopy, bond vibration frequency, antibacterial activity, disc diffusion assay, colony forming unit testing, S. marcescens, E. cloacae, E. coli, ultraviolet‐visible spectroscopy, protein kinase inhibition assay, cytotoxicity, lethal infections, ZnO     

In-vitro antioxidant and antibacterial activities of pumpkin,quince, muskmelon and bottle gourd seeds

Ethanol and chloroform extracts of pumpkin, quince, muskmelon, and bottle gourd seeds were studied for in-vitro antioxidant and antibacterial activities. Crude protein and fat contents of all the seeds compared favorably with high protein legumes and high oil containing oilseeds. Ethanol and chloroform extracts of bottle gourd seeds had highest phenolic content. A direct positive relationship between antioxidant activities and extract concentration was observed with the relationship being more pronounced in chloroform extract of quince seeds (R²?=?0.9685 and 0.9829) followed by ethanol extract of pumpkin seeds (R²?=?0.9666 and 0.9685) as per 1,1-diphenyl-2-picrylhydrazyl and hydrogen peroxide (H₂O₂) method, respectively. Seed extracts were also studied for in-vitro antibacterial activity against Salmonella typhii, Enterococcus sp., Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Ethanol extract of pumpkin seeds inhibited the growth of all bacteria; however, both the extracts of quince seeds did not show any activity against S. typhii, E. coli and S. aureus.