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High resolution FTS sunspot umbral spectra from NSO/Kitt Peak were used to detect rotational lines due to 11 electronic transitions of the molecule AlF, in the wavelength region 4400 -9000Å. The presence of lines due to bands C -A (0,0), (0,1), (0,2) and (1,2), D -A (0,0) and (0,1), F -A (0,0), G -A (0,0), and F -B (0,0) is confirmed. Further, the presence of lines due to C -A (1,0) and (1,1) transitions is treated as doubtful because of heavy blending in the region, by rotational lines of TiO. Among the identified lines, those which are well resolved were selected for measurement of equivalent widths. The measured values for the bands D -A (0,0) and F -A (0,0) were used to estimate the respective effective rotational temperatures to be 1240 ± 120 K and 2390 ± 400 K.

A high resolution spectrum of FTS sunspot umbra of NSO/Kitt Peak was used to conduct a search for the molecular absorption lines due to BeH, BeD and BeT isotopomers. Analysis led to estimates of identification of the molecular lines of bands A -X (0,0), (1,1) and (2,2) for BeH, A -X (0,0), (1,1), (2,2) and (3,3) for BeD and of A -X (0,0), (1,1) and (2,2) for BeT. Among the identified lines, those which are well resolved were selected for measurements to calculate equivalent widths. The values of effective rotational temperature T were estimated for bands A -X(1,1) and (2,2) of BeH, A -X(1,1) of BeD and A -X(2,2) of BeT to be 4228K, 4057K, 3941K and 3243K respectively.

Nanostructured Sn-doped TiO 2 have been prepared by ball milling using SnO 2 and TiO 2 as raw materials. The as-prepared powders are characterized by XRD, SEMs and EDAX to identify the structural phases, surface morphology, and composition of the materials. The materials are prepared with the addition of tin of different molar ratios (0, 0.05, 0.10, 0.15, 0.20, 0.25, and 1.0) to TiO 2 and sintered at 800• C for 3 h. They are subjected to dc resistance measurements as a function of relative humidity (RH) in the range of 30%-97% in a self-designed humidity chamber, and the results revealed that the sensitivity factor increased with an increase in tin molar ratio. Among them, TiO 2 -20 wt% of SnO 2 possessed the highest humidity sensitivity, while the pure TiO 2 and SnO 2 composite possessed a low sensitivity.

Ti -doped ZnO (TixZn1-xO x= 0.00, 0.05, 0.10, 0.15) nanoparticles have been synthesized through co -precipitation approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), UV-Visible spectroscopy, and Vibrating Sample Magnetometer (VSM) have been used to characterize the samples. X-Ray Diffraction (XRD) analysis manifested the hexagonal wurtzite structure. The crystallite size decreased from 37 nm to 29 nm as dopant concentration is increased. Fourier transform infrared analysis showed the absorption bands of ZnO, with few within the intensities. SEM investigation showed the irregular shape and agglomeration of the particles. Ti, Zn, and O composition were determined from EDX analysis and confirmed the purity of the samples.PL spectra showed a near band edge emission and visible emission.Vibrating sample magnetometer (VSM) demonstrated pure and doped samples exhibited ferromagnetism behavior at room temperature.

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