Comparative studies of bismuth and barium boro-tellurite glass system: structural and optical properties

This paper aims to compare the structural and optical properties of ternary Boro-tellurite glass with the addition of two different chemical modifier. Six glass samples from composition [(TeO2)0.7 (B2O3)0.3]1-x (BaO)x (x = 0.10, 0.20 and 0.30 mol%) and [(TeO2)0.7 (B2O3)0.3]1-x (Bi2O3)x (x = 0.10, 0.20 and 0.30 mol%) were prepared by melt quenching method with suitable melting and quenching temperature. The X-ray diffraction (XRD) pattern confirms the amorphous nature of all glasses and the Fourier transform infrared spectroscopy (FTIR) spectra explore the fundamental groups and the local structural units in two different boro-tellurite glasses. The density for both glass series increased as barium oxide and bismuth oxide content increased. The optical band gap, Eopt values for bismuthboro-tellurite glasses are between 2.15–2.4 eV, while barium-boro-tellurite glasses are between 2.25–2.44 eV. The highest concentration of Bi2O3 in glass system shows the smallest Eopt. In conclusion, the obtained results shows that the addition of bismuth oxide in boro-tellurite glass improves its structural and optical properties

Linear and nonlinear optical properties of Gd3+ doped zinc borotellurite glasses for all-optical switching applications

In this work, linear and nonlinear optical parameters of zinc borotellurite glasses doped with Gd3+ have been studied for all-optical switching applications. A series of gadolinium zinc borotellurite glasses were synthesized by using conventional melt quenching technique. Optical absorption spectra were recorded by UV–vis spectroscopy. From the optical absorption spectra, the cut-off wavelength, optical band gap, Urbach energy and refractive index have been determined and are related to the structural changes in the glass systems. The nonlinear optical properties of Gd3+ doped glasses are investigated by using Z-scan technique. The values of nonlinear refractive index and absorption coefficient with closed and opened apertures of the Z-scan, respectively, were determined for proper utilization in nonlinear optical devices. Keywords: Gadolinium, Rare earth, Borotellurite glass, Optical band gap, Refractive index, Nonlinear optical propertie

Primary liver cells cultured on carbon nanotube substrates for liver tissue engineering and drug discovery applications

Here, we explore the use of two- and three-dimensional scaffolds of multiwalled-carbon nanotubes (MWNTs) for hepatocyte cell culture. Our objective is to study the use of these scaffolds in liver tissue engineering and drug discovery. In our experiments, primary rat hepatocytes, the parenchymal (main functional) cell type in the liver, were cultured on aligned nanogrooved MWNT sheets, MWNT yarns, or standard 2-dimensional culture conditions as a control. We find comparable cell viability between all three culture conditions but enhanced production of the hepatocytespecific marker albumin for cells cultured on MWNTs. The basal activity of two clinically relevant cytochrome P450 enzymes, CYP1A2 and CYP3A4, are similar on all substrates, but we find enhanced induction of CYP1A2 for cells on the MWNT sheets. Our data thus supports the use of these substrates for applications including tissue engineering and enhancing liver-specific functions, as well as in in vitro model systems with enhanced predictive capability in drug discovery and development