Results of differential scanning calorimetry (DSC) studies of Se₈₅Te_15−xPb_x (x = 4, 6, 8 and 10) glasses have been reported and discussed in this paper. The results have been analyzed on the basis of structural relaxation equation, Matusita’s equation and modified Kissinger’s equation. The activation energies of structural relaxation lie in between 226 and 593 kJ/mol. The crystallization growth is found to be onedimensional for all compositions. The activation energies of crystallization are found to be 100–136 kJ/mol by Matusita’s equation while 102–139 kJ/mol by modified Kissinger’s equation. The Hruby number (indicator of ease of glass forming and higher stability) is the highest for Se₈₅Te₉Pb₆ glass while S factor (indicator of resistance to devitrification) is highest for Se₈₅Te₇Pb₈ glass at all heating rates in our experiment. Further the highest resistance to devitrification has the highest value of structural activation energy and the activation energy of crystallization is maximum for the most stable glass by both Matusita’s equation and the modified Kissinger’s equation.

Differential scanning calorimeter (DSC) is employed to study the crystallization kinetics of irradiated (at three different fluences with high-energy heavy ion; Ni¹¹⁺ of 150 MeV) specimens of two Co-based metallic glasses. It is found that the crystallization process in both the glasses is completed in two phases. The DSC data have been analysed in terms of kinetic parameters viz. activation energy (𝐸_𝑐), Avrami exponent (𝑛), dimensionality of growth (𝑚), using two different theoretical models. The results obtained have been compared with that of virgin samples. The lower activation energy in case of second crystallization occurring at higher temperature indicates the easier nucleation of second phase. The abnormally high value of Avrami exponent in Co–Ni glass indicates very high nucleation rate during first crystallization.

Measurements of thermal conductivity and thermal diffusivity of twin pellets of Se₈₀Te_20–𝑥In_𝑥 (𝑥 = 2, 4, 6 and 10) glasses, prepared under a load of 5 tons were carried out at room temperature using transient plane source (TPS) technique. The measured values of both thermal conductivity and diffusivity were used to determine the specific heat per unit volume of the said materials in the composition range of investigation. Results indicated that both the values of thermal conductivity and thermal diffusivity increased with the addition of indium at the cost of tellurium whereas the specific heat remained almost constant. This compositional dependence behaviour of the thermal conductivity and diffusivity has been explained in terms of the iono-covalent type of bond which In makes with Se as it is incorporated in the Se–Te glass.

Nanocomposites of Ni–Zn with copolymer matrix of aniline and formaldehyde in presence of varying concentrations of zinc ions have been studied at room temperature and normal pressure. The energy band gap of these materials are determined by reflection spectra in the wavelength range 400–850 nm by spectrophotometer at room temperature. From the analysis of reflection spectra, nanocomposites of copolymer of aniline and formaldehyde with Ni$_{1–x}$Zn$_x$Fe₂O₄ (𝑥 = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) have been found to have direct band gaps ranging from 1.50–1.66 eV.

The results of differential scanning calorimetric (DSC) measurements on Ge₂₀Se_80–𝑥As_𝑥 (𝑥 = 0, 5, 10, 15 and 20) system with the specific aim of investigating the effect of heating rate and composition on glass transition temperature have been discussed. The results indicate that the glass transition temperature (𝑇_𝑔) is dependent both on the heating rate and composition. The glass transition activation energy (𝐸_𝑡) and heat absorbed in glass transition region (𝛥𝐻) are higher for Ge₂₀Se₆₅As₁₅ as compared to the values of other compositions of arsenic. An effort has also been made to develop an empirical model for the composition dependence of 𝛥𝐻. A good agreement has been observed between the experimental values and the results of model calculation.

The 𝐼–𝑉 characterization and the electrical resistivity of selenium rich Se₈₅Cd_15–𝑥Zn_𝑥 (𝑥 = 0, 3, 7, 11 and 15) system at room temperature have been studied. Samples were obtained using melt cooling technique. So prepared samples were then characterized in terms of their crystal structure and lattice parameter using X-ray diffraction method. The materials were found to be polycrystalline in nature, having zinc blend structure over the whole range of zinc concentration. The measurements of 𝐼–𝑉 characteristics have been carried out at different temperatures from room to 140°C. The electrical resistivity of the samples with composition at room temperature has been found to vary between maximum 2.7 × 10⁸𝛺 m and minimum 7.3 × 10⁵𝛺 m and shows a maximum at 3 at. wt.% of Zn. The carrier activation energy of the samples with composition has also been determined and found to vary from 0.026 eV to 0.111 eV.

Chemical method has been used to prepare cadmium sulphide by using cadmium, hydrochloric acid and H₂S. The reflection spectra of covered and uncovered sintered films of CdS have been recorded by ‘Hitachi spectrophotometer’ over the wavelength range 300–700 nm. The energy band gaps of these films have been calculated from reflection spectra. It is found that the energy band gap of both films is same as 2.41 eV. It is indicated that energy band gap of these films does not change. This value of band gap is in good agreement with the value reported by other workers. The measurement of photocurrent has also been carried out using Keithley High Resistance meter/ Electrometer. This film shows the high photosensitivity and high photocurrent decay. Thus so obtained films are suitable for fabrication of photo detectors and solar cells.

The present paper reports the composition dependence of pre-exponential factor and activation energy of non-isothermal crystallization in amorphous alloys of Cu_𝑥Ti_100–𝑥 system using differential scanning calorimeter (DSC) technique. The applicability of Meyer–Neldel relation between the pre-exponential factor and activation energy of non-isothermal crystallization for amorphous alloys of Cu–Ti system was verified.

Electrical conductivity of chalcogenide glassy system Ge$_{30−x}$Se$_{70}$Sb$_{x}$ (𝑥 = 10, 15, 20 and 25) prepared by melt quenching has been determined at different temperatures in bulk through the $I$–$V$ characteristic curves. It is quite evident from results that Poole–Frenkel conduction mechanisms hold good for conduction in these glasses in a given temperature range. The variation in electrical conductivity with composition was attributed to the Se–Sb bond concentration in the Se–Ge–Sb system. Results indicated that Ge$_5$Se$_{70}$Sb$_{25}$ showed the minimum resistance. In view of this the composition Ge$_5$Se$_{70}$Sb$_{25}$ may be coined as ‘critical composition’ in the proposed series. Also the activation energies of conduction of these glassy alloys have been calculated in higher and lower temperature range using the Arrhenius equation.