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Nanomaterials of copper and cobalt were formed in alcohol in a novel way. Incorporation of these materials by simple solution casting technique in poly vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) polymer films significantly improves their electrical properties. These films have higher dielectric permittivity and lower dissipation factor (tanδ) at room temperature, compared to the pure PVDF-HFP. The incorporation can be used to increase the dielectric constant of the pure film at 20 Hz frequency upto a maximum of four times. Presence of α- and β-phases and spherulitic crystal structure of PVDF-HFP of these nanocomposite films have been detected by XRD, FTIR, DTA and FESEM studies. The incorporation of the nanomaterial in the polymer matrix activates the transition of phase between α and β. This provides higher mobility of the charge carriers which participate in the interfacial polarization. These nanoparticles are easy to fabricate and environment friendly and their presence in polymer matrix to get enhanced electrical properties will have a significant contribution in the present day research in electronics.

Use of Azo dyes, having one or more azo bond (-N=N-), are more than 70% among all textile dyes used. The stability and the xenobiotic nature of reactive of these azo dyes make them recalcitrant and hence they are not totally degraded by conventional wastewater treatment processes that involve physical, chemicals or activated sludge methods. The dyes are therefore released into the environment, in the form of colored waste water. Color of the waste effluent is an important parameter for a long time. So the main criteria of removing the waste and degrade is to first remove the color of the effluent. Some common techniques which are used for degrading the chemically complex dye have several harmful side effects and they are not very cost effective and some require long retention time. So extensive research is going on to find a simple method which should obviously be a low cost process, will need less time to complete the process and will have minimum harmful side effects.

Synthesis and characterization of Carbon nanotube/Hydroxyapatite/Clay based Hybrid antimicrobial biomaterial for potential tissue engineering application Subrata Kara,b, Papiya Nandyb, Ruma Basub,c and Sukhen Das*a,b,d aPhysics Department, Jadavpur University, Kolkata-700 032, India. bCentre for Interdisciplinary Research and Education, Kolkata 700 068, India cPhysics Department, Jogamaya Devi College, Kolkata 700 026 dIndian Institute of Engineering, Science and Technology, Howrah, India *Corresponding author Inorganic ceramic materials have recently been enjoying a great deal of attention for uses as biomaterial over the traditionally used polymeric material. The ability of silica based ceramics to release Si-containing ionic products makes them osteoconductive and their special surface composition has drawn considerable attention for its use as osteogenic proliferation, differentiation and gene expression of tissue cells. Here Pristine Multiwalled carbon nanotube (MWCNT) was functionalized by acid oxidation and used as template for nucleation of hydroxyapatite crystal. The CNT-HAP thus formed was further reinforced with exfoliated Montmoriollite(MMT) clay to increase the mechanical property of the nanocomposite. The synthesized composite viz CNT-HAP (HC) and CNT(HAP)-MMT(CHC) were characterized by fourier transform infrared spectroscopy(FTIR), X-ray diffraction(XRD), Scanning electron microscopy and transmission electron microscopy(TEM) and thermogravimetric analysis(TGA) . The biomedical application of CHC, blood compatibility was studied in terms of hemolysis assay and platelet adhesion assay. Finally, in vitro dissolution assay and the antibacterial activity of the material were further explored for establishing its use as an antibacterial biomaterial. The nanocomposite thus designed exhibited a promising candidate as an antimicrobial biomaterial for tissue Engineering application.

In the crisis of fast diminishing fossil fuels, looking for alternative energy sources by utilizing solar energy has the highest research priority and engineered nanoparticles play a very important role here. Using a specially designed photoelectrochemical cell and a mixture of two dyes, Phenosaffranine (PSF) and Azure C (AZC) conjugated with oxidized multi-walled carbon nanotubes (OMWCNTs) we have been able to generate photovoltage of reasonably high magnitude (763 mV). The storage time is also quite high ~ 66 hrs. The photovoltage cycle was reproducible upon further illumination. Energy conversion efficiency (η%) of the cell has been calculated for the system (η% = 4.33). Spectral studies show that with addition of OMWCNTs to a fixed concentration of PSF and AZC solution, the absorbance increases throughout the spectral range. FTIR spectrum reveals that there is no chemical change in the mixed system indicating that only the dyes got adsorbed on the side walls on the OMWCNTs. From fluorescence spectral study, it has been seen that while fluorescence intensity of PSF quenches with addition of AZC, which does not have any fluorescence of its own, the intensity regains with addition of OMWCNTs. This emphasizes the role of oxidized multi-walled carbon nanotubes in the performance of photoelectrochemical cell of mixed dye system.