Nanocomposite Obtained in the Plasma of a Pulsed High Voltage Discharge Using Nickel Electrodes and PTFE

In the plasma of pulsed high-voltage discharge, initiated between nickel electrodes in air, when the fluoroplastic is placed in the discharge gap, powder nanocomposite material has been synthesized. The nanocomposite contains NiF2 nanoparticles less than 5 nm in size, dispersed in a matrix consisting of carbon and fluorocarbon substances. The carbonaceous substance contains nanoscale disordered graphite-like regions. The fluorocarbon component of the composite contains fragments of PTFE molecules and fluorocarbon molecular fragments that differ in structure from PTFE molecule’s structure. After annealing the composite in air at 773 K, the initial nanocomposite is transformed into a nanocomposite containing nanosized PTFE and nanoparticles of NiF2 less than 5 nm in size, scattered in a matrix composed of nanographite and low-layer nanosized graphene, after aneling at 1173 K into a material containing NiO nanoparticles less than 10 nm in size. After annealing of the initial nanocomposite in argon atmosphere at 1073 K, the obtained nanocomposite contains Ni nanoparticles with sizes less than 5 nm and carbon and fluorocarbon components. The magnetic susceptibility of the unannealed nanocomposite is investigated. A transition to the antiferromagnetic phase at 73 K was detected. At T = 4K, exchange bias interaction of the AFM / FM type takes place in the composite. There is divergence of the FC and ZFC curves, which can be explained by the presence of a superparamagnetic phase or a spin glass phase in the sample. The field dependences of the magnetic susceptibility measured at T = 300 K show sharp changes that occur at certain values of the magnetic field. Elucidation of the nature of these changes requires additional research.

Excitonic States and Related Optical Susceptibility in InN/AlN Quantum Well Under the Effects of the Well Size and Impurity Position

Based on the finite difference method, linear optical susceptibility, photoluminescence peak and binding energies of three first states of an exciton trapped by a positive charge donor-impurity ( ) confined in InN/AlN quantum well are investigated in terms of well size and impurity position. The electron, heavy hole free and bound excitons allowed eigen-values and corresponding eigen-functions are obtained numerically by solving one-dimensional time-independent Schrödinger equation. Within the parabolic band and effective mass approximations, the calculations are made considering the coupling of the electron in the n-th conduction subband and the heavy hole in the m-th valence subband under the impacts of the well size and impurity position. The obtained results show clearly that the energy, binding energy and photoluminescence peak energy show a decreasing behavior according to well size for both free and bound cases. Moreover, the optical susceptibility associated to exciton transition is strongly red-shift (blue-shifted) with enhancing the well size (impurity position).

Nanocomposite Formulation of Ferulic Acid with Different Metals Using Computational Method

Formulation of Nanoparticle – drug composite is becoming a growing field of research in today’s scientific community. In comparison to the research on the experimental methods for these formulations and their application in various fields, the study of the interaction between drug and nanoparticle is less. In this study, we are reporting about the selection of metals for the formulation of nanocomposite with ferulic acid which is a well-known bioflavonoid having different medicinal activities. Ferulic acid contains only one –OH group which may reduce the conflict of selecting the metal atom binding site. For our study, we considered twelve metals which have been reported for having the potentiality to synthesis nanoparticles. These metals are gold, silver, copper, iron, zinc, nickel, platinum, palladium, rhodium, ruthenium, cadmium, and antimony. To mimic the actual nanocomposite structure, one metal atom has interacted with two molecules of ferulic acid. All nanocomposite model structures were designed using Avogadro software for windows. It was subjected to energy minimization and O-metal-O bond angle calculation. From the energy levels, it was observed that cadmium exhibited the lowest energy level and antimony showed the highest energy level suggesting their nanocomposite model structures as the most stable and unstable formulation respectively.

Solubility of Mn in ZnO Crystallites Synthesized Using Solid State Techniques

Powder samples of Zn1-xMnxO nanocrystal were synthesized at a temperature of 200 °C using solid phase method. Dopant concentrations of 0.005 ≤ x ≤ 0.5 were studied. Powder x-ray diffraction (PXRD) patterns of the samples were analyzed with a view of determining the onset of secondary phases, hence the solubility limit of the dopant. The solubility limit for Mn in ZnO samples synthesized at 200 °C is realized at x < 0.3. With a regular pattern in increment of the Mn concentration, there were variations observed in the trend of the relative intensity, 2θ position and d-spacing indicating uneven addition of Mn (thus Mn2+, Mn3+ or Mn4+).

Green Synthesis of Zinc Oxide Nanoparticles via Algal Route and its Action on Cancerous Cells and Pathogenic Microbes

Application of metal oxide nanoparticles for treatment of melanoma cells and microbes is being investigated. Zinc oxide nanoparticles (ZnO NPs) deserve special mention where particles cause destruction of melanoma cells with minimal damage to healthy cells. In the present study, pure phase ZnO NPs with particle size of 3.1 nm were synthesized by green route using algal extract. Skin melanoma (B16F10) cells were treated with synthesized ZnO NP and compared with commercial ZnO NPs and analysed for ED50 for cellular viability using 3% (w/v) of the doses. Sensitivity of B16F10 cells towards green synthesized ZnO NP was found to be more than commercial ZnO NPs. Results showed greater reduction in viability of cells exposed to green synthesized ZnO NPs and with increasing dose of the ZnO NPs, percentage viability of cells gradually reduced. 50% decrease in cellular viability (ED50) was obtained for green synthesized ZnO NP at 3% dose while commercial ZnO exhibited ED50 at 6% of doses. The ZnO NP also showed antimicrobial activity against Pseudomonas sp. and Staphylococcus sp. Zone of inhibition (ZOI) exhibited by Pseudomonas aeruginosa and Staphylococcus aureus for disc diffusion and well diffusion assay was around 10-22 mm and 9-12mm respectively.

Green Synthesis of Silver Nanoparticles Using Waste Tea Leaves

Green synthesis of silver nanoparticles has gained momentum since the demand to synthesize nanoparticles in an eco-friendly way has increased significantly. Here we report, economic and cost-effective biosynthesis of silver nanoparticles using waste of tea leaves (Camelia sinesis). The aim of the study was to biosynthesize silver nanoparticles and to assess its potential applications such as antibacterial activity, plant growth induction and dye degradation. Standardization studies were done using UV- Spectroscopy to determine the optimum synthesis condition for synthesis of silver nanoparticles. The optimum conditions were found to be pH 6.0, ambient temperature condition and 5mM AgNO3 concentration. Characterization studies using UV-Visible Spectroscopy, TEM and AFM analysis show nanoscale range of the particles. The silver nanoparticles showed maximum antibacterial activity against K. pneumonia followed by E. coli and minimum activity against C. diptheriae. The nanoparticles showed significant effect on the growth of Vigna radiata seeds at 50% concentration of nanoparticles. The particles immobilized on cotton cloth showed antibacterial activity against Gram positive organisms. Dye degradation studies showed that the nanoparticles are able to degrade phenol red and blue textile dye effectively.

Solubility of Mn in ZnO Nanocrystallites using Wet Chemical Synthesis

There is a substantial amount of literature dealing with many aspects of synthesis and characterization of pure and doped binary compounds including Mn-doped ZnO which has been widely studied due to its superb properties as a dilute magnetic semiconductor (DMS). Aspects concerning doping limits for these compounds is an important stage in the search for new materials. Samples of Zn1-xMnxO nanocrystal were synthesized at temperatures of 180 °C and 200 °C using wet or liquid phase synthesis method. Dopant concentrations x=0.5, 1, 1.5, 2, 2.5, 5, 10, 20, 30, 40 and 50 per cent were studied. Powder x-ray diffraction (PXRD) patterns of the samples were analyzed with a view to determining the onset of secondary phases and hence the solubility limit of the dopant. The solubility limit for Mn in ZnO samples synthesized at temperature of 200 °C is realized at x <20%. For samples synthesized at temperature of 180 °C, the solubility limit is x <0.5%.

Mechanistic Study of Antibacterial Properties of Chemically Synthesize Zinc Oxide Nanoparticles

Nanotechnology is the science, engineering and technology conducted at the scale that ranges between 1-100 nanometers. For the bio-application, evolution of nanotechnology is creating the concern of scientists towards the synthesis of nanoparticles. The nanoparticles have unique characteristics as compare to bulk materials. Zinc oxide (ZnO) is a matchless semiconductor and it has been under investigation due to its wide range of applications in various areas like biomedical, electronics, material science and optics. In the present work synthesis of ZnO nanoparticles was carried out by using simple chemical approach, Sol-gel method for being effective and inexpensive, by employing zinc acetate dehydrate Zn (CH3CO2)2.2H2O as a precursor and sodium hydroxide (NaOH) starch as a constant agent. The structural properties of resultant zinc oxide nanoparticles were investigated by X-ray diffraction (XRD) technique. The XRD data confirmed the hexagonal wurtzite structure of ZnO powder confirmed by JCPDS 36-1451 data. Particles size was calculated by Scherrer formula and calculated size was 30.14 nm. These nanoparticles were investigated for inhibition zone of bacterial strain Escherichia coli, a gram-negative microbe, at various concentrations of ZnO nanoparticles. Zinc oxide nanoparticles were very proficient for inhibition of growth of bacterial strain E. coli. The mechanism of ZnO NPs for antibacterial activity is release of reactive oxygen species which not only hydrolyze cell wall but cell membrane and cellular components as well providing a potential bactericidal effect.

Mechanical Characterization of Nanomaterial Reinforced Aluminum-based Hybrid Nanocomposites

Nanostructures are viewed as definitive fiber materials as a reinforcement for matrices because of their impressive properties. Because of their phenomenal mechanical properties Carbon nanotubes (CNTs), graphene (GR), and nanodiamond (ND) have made an enormous proportion of intensity in research over the world. Multiwalled carbon nanotubes (MWCNTs), Graphene, and Nano Diamond were utilized as reinforcements for the current work. Nanostructures with their extraordinary strength, minute size, and high aspect ratio were used as reinforcements in commercial-purity Al matrix. These nanocomposites were manufactured by various different routes such as casting and powder metallurgy techniques. Both of these methods are helpful for the preparation of MWCNTs/Al nanocomposites. These nanocomposites were manufactured with various weight fractions of reinforcements and characterized for their mechanical properties and indicated improved properties in contrast with the base Al matrix. Al/MWCNT nanocomposites, Al/MWCNT/GR hybrid nanocomposites and Al/MWCNT/GR/ND hybrid nanocomposites samples were tested for their mechanical properties such as Young’s modulus, percentage elongation yield strength, and ultimate Strength. Mechanical characterization of these prepared composite samples demonstrated improved strength when compared with the casted samples.

Green Peptide–nanomaterials; A Friendly Healing Touch for Skin Wound Regeneration

The complex phenomenon by which the body responds to any injury of skin or tissue is known as wound healing. A number of phases like exudative, proliferative, and extracellular matrix remodeling are orchestrated events to be occurred involving blood cells, parenchymal cells, and different soluble mediators. Different internal, as well as external factors, regulate the speed and quality of healing. The delay in wound healing process causes the chronic wound or scar formation. At the present moment, the upscale research for identification of agents causing accelerated healing is important. Moreover, the biocompatibility of the accelerators needs to be investigated. Recent biomedical researches for wound care target to provide antimicrobial protection as well as matrix scaffolding for quick repairing of the skin tissue. In recent studies with natural peptides have shown that they are important components in developing the nano-medicines for their usefulness and therapeutic efficiency. New therapeutic formulations can be developed using these natural peptides utilizing different nanoparticle delivery system. This review deals with the developmental study on efficient wound care system where the possible use of natural peptides in combination with nanomaterials has been explored. A trial has also been made on the findings made over the past few years on the use of peptides as tissue regenerating agents through effective wound healing pathway.