Vibrational analysis of Ag3(PO2NH)3, Na3(PO2NH)3.H2O, Na3(PO2NH)3.4H2O, [C(NH2)3]3(PO2NH)3.H2O and (NH4)4(PO2NH)4.4H2O

FT IR and FT Raman spectra of Ag3(PO2NH), (Compound I), Na3(PO2NH)3.H2O (Compound II), Na3(PO2NH)3.4H2O (Compound III), [C(NH2)3]3(PO2NH)3.H2O (Compound IV) and (NH4)4(PO2NH)4.4H2O (Compound V) are recorded and analyzed on the basis of the anions, cations and water molecules present in each of them. The PO2NH− anion ring in compound I is distorted due to the influence of Ag+ cation. Wide variation in the hydrogen bond lengths in compound III is indicated by the splitting of the v2 and v3 modes of vibration of water molecules. The NH4 ion in compound V occupies lower site symmetry and exhibits hindered rotation in the lattice. The correlations between the symmetric and asymmetric stretching vibrations of P-N-P bridge and the P-N-P bond angle have also been discussed

Elettaria cardamomum seed mediated rapid synthesis of gold nanoparticles and its biological activities

Plant mediated synthesis of metal nanoparticles has drawn the attention of researchers due to their unique features and extensive application in various fields. The present report is on the unexploited environmentally benign rapid synthesis of gold nanoparticles of size 15.2 nm using the aqueous extract of Elettaria cardamomum seeds. Studies on antioxidant, antibacterial and anticancer activities of the nanoparticles have been carried out. The invitro radical scavenging activity of the biogenic nanogold is found to be comparable to that of the reference. The as synthesized gold nanoparticles also exhibits antibacterial activity against a broad spectrum of bacterial pathogens. The antibacterial activity is found to be enhanced against S.aureus compared to E.coli and P.aeruginosa. Further, the obtained nanoparticles show excellent cytotoxic activity towards HeLa cancer cell lines

Simulation studies on the responses of ZnO-CuO/CNT nanocomposite based SAW sensor to various volatile organic chemicals

Surface acoustic wave (SAW) sensors offer a sensitive platform for monitoring important physical entities with several advantages. They can operate well in extreme conditions such as high temperature, high pressure and toxic environment. This work presents a 2D model of SAW sensor with carbon nano tubes (CNT) as the adsorbent material. A second model was also created by incorporating ZnO and CuO nanospheres into the sensing layer. The responses of the two sensors towards various gases were analysed at room temperature. The design was modelled and analysed using COMSOL Multiphysics software which applies the finite element analysis to solve for Eigen frequencies. The shift in the resonant frequencies with and without the presence of gases, which is a measure of sensitivity has been estimated for all the gases. The second model showed improved response. This novel ZnO-CuO/CNT SAW sensor combining the sensing properties of metal oxide nanostructures and CNT with improved characteristics can be used as a promising candidate for sensing important volatile organic chemicals at room temperature. Keywords: ZnO, CuO, Surface acoustic waves, Sensors, Carbon nano tube