The shuriken effect of fertile alpha emitters : a physical process behind findings of chemical toxicity of depleted uranium
This letter is a contribution on the study of nanoparticles for in situ observation and general understanding of nanoparticle physics. The positing that “chemical” effects from alpha emitters found by researchers actually come from the particular physical effect demonstrated with firmness here is not always possible (as alpha decay also interferes) but a case where this is definitive is given.
Most of the killed, inactivated, or live-attenuated pathogen vaccines are now replaced by modern vaccines containing isolated, highly purified antigenic protein subunits which are safer than live viruses or deactivated viruses. Another strategy is the development of nanoparticles which can mimic the repetitiveness, geometry, size and shape of the host-pathogen surface and provide improved stability and long lasting immunogenicity, as well as serve as vehicles to deliver multiple copies of the antigens to the target cells. Several interesting advances have been made recently in the area of protein nanotechnology and here, we provide a concise review of one such novel nanoparticle called FluoDot which may be effectively used as a delivery system in some veterinary medicine applications.
A Semi Organic Non-linear Optical Crystal: Synthesis, Growth and Characterization of Novel Thiosemicarbazide Magnesium Chloride
Single crystals of thiosemicarbazide magnesium chloride (TSCMC) a semi organic nonlinear optical (NLO) material have been grown from aqueous solution by a slow evaporation technique. The grown crystals have been subjected to single crystal X-ray diffraction studies to identify of the structure. FTIR and optical transmission spectra reveal the optical properties of the grown crystals. The thermal behavior of TSCMC was investigated using the TG–DTA studies. Dielectric measurements were made over a wide range of frequencies for different temperatures. The second harmonic generation (SHG) efficiency for the grown crystals was determined using the Kurtz powder technique.
Studies on the comparison of antibacterial and catalytic activity of molybdenum Nanoparticle synthesized by chemical and biological method
Nanobiotechnology holds a great potential in various fields of life sciences. Nanotechnology involves the use of materials with components that have dimensions less than 100nm. The demand for biosynthesized nanoparticles increased day by day due to its ecofriendly and compatibility when compare to chemical method of synthesis. Application of nano-sized materials is an emerging area of nanotechnology. Molybdenum (Mo) nanoparticle was synthesized using fast, convenient, eco-friendly biological method from the aqueous extract of plumbago zeylanica. The same was synthesized using sol-gel method also. The nanoparticles synthesized by both the methods were characterized by Fourier transform infrared spectroscopy (FTIR), ultra violet spectroscopy (UV), scanning electron microscopy (SEM) and x-ray diffraction spectroscopy (XRD) studies. Molybdenum nanoparticles were found to be inhibiting the growth of bacteria and also act as effective catalyst.
Synthesis, Characterization and Catalytic Activity of Melamine-Based Dendrimer Encapsulated Pd/Cu Bimetallic Nanoparticles
A melamine-based dendrimer was used to prepare a new class of heterogeneous Pd/Cu bimetallic nanoparticles (NPs). The physicochemical characteristics of Pd/Cu bimetallic NPS were studied with the aid of SEM, EDX, XRD, TG& DSC techniques. Leafs shape surface morphology and the presence of required palladium and copper ion were observed from SEM and EDX analysis respectively while TG& DSC showed good thermal stability, as well as XRD, revealed nano-shape FCC structure. The recycling ability of the catalyst was examined for five successive runs without any noteworthy loss of activity. The synthesized Pd/Cu bimetallic NPS exhibited high catalytic activity in the synthesis of ynone in which synthetic route was phosphine ligand-free.
Synthesis of Diazine-Based Dendrimer Supported Pd/Co Bimetallic Nanoparticles and Catalytic Activity for Sonogashira Coupling Reactions
A moisture-stable diazine-based dendrimer assisted heterogeneous bimetallic Pd/Co nanoparticles (NPs) was synthesized which showed a simple, profitable and environmentally sustainable operation for the Sonogashira reactions under copper and solvent-free conditions with regained easily and recycled four times without substantial activity loss. Furthermore, the dendrimer was analyzed by IR, 1H NMR, 13C NMR, and elemental analysis whereas the Pd/Co bimetallic NPs was characterized by EDX, TGA & DSC, and XRD techniques.
MHD Mixed Convection Flow of Casson Nanofluid past a Stretching Sheet in the Presence of Viscous Dissipation, Chemical Reaction and Heat Source/Sink
This paper focuses on the effect of MHD mixed convection flow of casson nanofluid past a stretching sheet in the presence of viscous dissipation, first order chemical reaction and heat source/sink. The profiles for the velocity, temperature and nanoparticle concentration depends on the parameters Casson fluid parameter β, concentration buoyancy parameter N, Hartman number M, radiation parameter R, Prandtl number Pr, the Schmidt number Sc, Brownian motion Nb, thermophoresis parameter Nt, Eckert number Ec, chemical reaction parameter γ the heat transfer Biot number γ1 and the mass transfer Biot number γ2. The constitute governing partial differential equation of flow, heat and mass transfer on considered flow are converted into nonlinear ordinary differential equations by employing suitable transformations and these transformed equations were solved by the Adam’s Moultan fourth order method with shooting technique. The various numerical tables are calculated and tabulated. Our results have been compared with the results of a previous study and found to be in an excellent agreement.
Synthesis of Punica Granatum Fruit Peel Extract Based Silver Nanoparticles and Evaluation of it’s Antimicrobial Activity
The main objective of the present work was to prepare pomegranate peel extract based nano particles by chemical complexation method. Ethanolic extracts of pomegranate peel were prepared by using Soxhlet apparatus and evaluated for phyto-chemical constituents. Qualitative analysis showed that pomegranate peel extract showed positive results for alkaloids, anthraquinones, saponins and terpenoids. The percentage moisture content and pH of the extract was found to be 72% and 3.6 respectively. A zeta potential and particle size of prepared nanoparticles was found in the range of -24.6 to– 34.5 mV and 118.6 nm to 231.7 nm, respectively. These range confirms that obtained particles were in nano range, i.e.
Composite materials get an importance in value as an advance materials such as automotive, aerospace, aircraft, defense, medical, marine, sports, recreation and various engineering applications due to their high strength-to-weight ratio, good cast ability and better tribological properties. Al-base 2024 alloy reinforced with SiC micron and nano particles were developed using stir casting technique due to low cast, ease in fabrication, recyclability and isotropic characteristics. The development of Aluminum metal matrix nano composites (AMMNCs) is most considered material for high temperature applications because of their excellent mechanical properties, increase performance and weight saving for more reduction of fuel consumption. The results indicate that Al-SiC composite has improved physical and mechanical properties such as tensile strength, charpy impact strength, brinell hardness, density and porosity percentage. Samples with micron particles and nano particles were developed to compare the properties of both. Microstructures of the samples were studied by means of X-Ray Diffraction and Scanning Electron Microscopy. The elemental composition was also analyzed through Energy Dispersive Spectroscopy. It was found that composites of Al-SiC have better and improved physical properties in nano dimensions.
Synthesis of Biocompatible carboxylic acid functionalized Graphene Oxide as a stimulator of bacterial growth
Researchers have shown great interest towards Graphene and its potential applications in various fields such as electronics, energy, materials and biomedical areas. The effects of Graphene, graphene oxide (GO) and its derivatives on bacteria activities is still controversial. Thus, how graphene and its derivatives interact with microorganisms and the mechanisms of their interactions are important issues for nanotechnology which need proper exploration. In the present investigation, graphene oxide (GO) has been synthesized and functionalized by the chemical method. The GO and COOH-functionalized GO have been characterized by Fourier transforms infrared spectroscopy; Raman spectroscopy and SEM analysis. Further, haemocompatibility study has been performed to check the biocompatibility of functionalized graphene oxide. The effect of GO and COOH-GO on the bacterial growth has been observed. The FTIR, Raman and SEM data confirm the successfully functionalization of GO with carboxyl (-COOH) group. The haemolysis test shows that GO and GO-COOH are highly hemocompatible. Interestingly, functionalized graphene oxide, can significantly stimulate bacterial growth for gram positive and gram negative bacteria, whereas as-made GO shows no effect. It can be concluded that carboxylic acid functionalized GO may act as a new, positive regulator for the growth of bacterial cells.