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[en] In this paper, the economics analysis of water production by using different solid desiccant materials and composite materials through Scheffler reflector is presented. The experiments for water production have been performed at National Institute of Technology, Kurukshetra, Haryana, India [29°58′ (latitude) North and 76°53′ (longitude) East]. The various factors have been carried out to calculate the annual cost/liter in Indian currency. Total six cases are studied, and for each case, uniform procedure is adopted. The silica gel gives the best economical annual cost/liter compared to molecular sieve and activated alumina in case of solid desiccant, and for composite material, it is CaCl2/River Sand compared to LiCl/River Sand and LiBr/River sand.
[en] Various perovskite (Ba,Sr)TiO3 borosilicate glasses were prepared by rapid melt-quench technique in the glass system ((Ba1-xSrx).TiO3)-(2SiO2.B2O3)-(K2O)-(La2O3). On the basis of differential thermal analysis results, glasses were converted into glass ceramic samples by regulated heat treatment schedules. The dielectric behaviour of crystallized barium strontium titanate borosilicate glass ceramic samples shows diffuse phase transition. The study depicts the dielectric behaviour of glass ceramic sample BST5K1L0.2S814. The double relaxation was observed in glass ceramic samples corresponding 80/20% Ba/Sr due to change in crystal structure from orthorhombic to tetragonal and tetragonal to cubic with variation of temperature. The highest value of dielectric constant was found to be 48289 for the glass ceramic sample BST5K1L0.2S814. The high value of dielectric constant attributed to space charge polarization between the glassy phase and perovskite phase. Due to very high value of dielectric constant, such glass ceramics are used for high energy storage devices. La2O3 acts as nucleating agent for crystallization of glass to glass ceramics and enhances the dielectric constant and retarded dielectric loss. Such glass ceramics can be used in high energy storage devices such as barrier layer capacitors, multilayer capacitors etc. (author)
[en] Perovskite (Ba,Sr)TiO3 borosilicate glasses in the system 64((Ba1-xSrx).TiO3)-30(2SiO2.B2O3)-5(K2O)-1(Fe2O3) (0.4 ≤x≥1.0) were prepared by conventional melt-quench method. Synthesized glass samples were characterized by infrared and Raman spectroscopic techniques for their structural investigations while optical properties of these glasses have been studied by using UV-Vis NIR spectroscopy. These investigations confirm the absence of boroxol ring in glassy matrix. Optical band gap of barium strontium titanate borosilicate glasses lies in the range 2.48-2.87 eV and its density has been found to be in the range 2.70-3.12 g/cc. (author)
[en] Bulk transparent barium strontium titanate borosilicate glasses in glass system (65-x)[(Ba_0_._6Sr_0_._4).TiO_3]-30[2SiO_2.B_2O_3]-5[K_2O]-x[A_2O_3], A = La, Fe (x = 2, 5 and 10) were prepared by rapid melt-quench technique and subsequently, converted into glass ceramics by regulated heat treatment process. The phase identification was carried out by X-ray powder diffraction and their surface morphology was studied by scanning electron microscopy. The dielectric properties were studied by impedance spectroscopic technique. Investigated glass samples were crystallized into major and secondary phases of Ba_1_._9_1Sr_0_._0_9TiO_4 and Ba_2TiSi_2O_8, respectively. A very high dielectric constant having value upto 68000 was found in glass ceramic sample BST5K10F. This high value of dielectric constant was attributed to interfacial polarization, which arose due to conductivity difference among semiconducting crystalline phases, conducting grains and insulating grain boundaries. Donor dopant La_2O_3 and acceptor dopant Fe_2O_3 play an important role for enhancing crystallization, dielectric constant and retardation of dielectric loss in the samples. Moreover, higher value of dielectric constant and lower value of dielectric loss was found in Fe_2O_3 doped samples in comparison to La_2O_3 doped samples. - Highlights: • Bulk transparent barium strontium titanate glasses are successfully prepared. • A very high dielectric constant upto 68000 was found in glass ceramics. • La_2O_3 and Fe_2O_3 play role for enhancing value of dielectric constant. • Higher dielectric constant with low dielectric loss was found in Fe_2O_3 doped sample. • Such glass ceramics may be used in making capacitors for high energy storage.