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we have detailed investigations on the influence of synchronous substitution Cd at the Ba place of HgBa2-xCdxCa2Cu3O8+δ cuprate superconductor with x=0 to 0.15, have been synthesized samples via using solid state reaction(SSR) method, All the specimens in the existent investigation were exposed to total characterization of structural via XRD. The X-ray diffraction information collected of different specimens correspond to (Hg-1223) phases and the analysis showed that tetragonal structure. Resistivity of electrical was utilizing the 4-probe technique to find the temperature of critical and found that Tc increase at addition Cd from (116 to 134)Ko . [ABSTRACT FROM AUTHOR]

This paper deals with the effect of BaO addition on the optical properties of bioactive Na2O-CaO-P2O5 glasses for biomedical optics applications. The phosphate glasses with composition (26-x)Na2O-xBaO-29CaO-45P2O5 (x = 0, 5, 10, 15 mol%) have been prepared by melt-quenching technique at 1100°C. The refractive index of glasses increased with BaO content. The optical band gap and Urbach energy of synthesized glasses were derived from the optical absorption spectra by using UV-Visible spectrometer. The addition of 5 mol% of BaO increased the band gap energy of glasses due to the formation of ionic cross-links in the glass structure. The defect and interstitial bonds formation in theglasses decreased with BaO additions as indicated by reductions in the Urbach energy values. No such variations in the band gap and Urbach energy values of glasses were observed with BaO content from 5 to 15 mol%. The molar and oxide ion polarizability values were calculated from the band gap and molar volume of glasses. The increase in the calculated optical basicity and metallization criteria of glasses supported the rise in band gap energy values with BaO additions. As the melting temperature of glasses decreased from 1200 to 1100°C, the refractive index increased as supported by the measured density values. The band gap energy is not changed with melting temperature. The Urbach energy decreased with decrease in melting temperature in case of BaO-free Na2O-CaO-P2O5 glasses, whereas it increased in case of BaO added glasses due to the role of BaO as modifying oxide. [ABSTRACT FROM AUTHOR]

The use of perovskite oxides as a medium for thermochemical energy storage (TCES) in concentrating solar power systems is reported. The known reduction/oxidation (redox) active perovskites LaxSr1-xCoyMn1-yO3 (LSCM) and LaxSr1-xCoyMn1-yO3 (LSCF) were chosen as a starting point for such research. Materials of the LSCM and LSCF family were previously synthesized, their structure characterized, and thermodynamics reported for TCES operation. Building on this foundation, the reduction onset temperatures are examined for LSCM and LSCF compositions. The reduction extents and onset temperatures are tied to the crystallographic phase and reaction enthalpies. The effect of doping with Ba and K is discussed, and the potential shortcomings of this subset of materials families for TCES are described. The potential for long-term stability of the most promising material is examined through thermogravimetric cycling, scanning electron microscopy, and dilatometry. The stability over 100 cycles (450-1050℃) of an LSCM composition is demonstrated. [ABSTRACT FROM AUTHOR]

The Morse potential is a potential model that is used to describe the anharmonic behavior of molecular vibration between atoms. The BaO and SrO molecules, which are two almost similar diatomic molecules, were investigated in this research. Some of their properties like the value of the dissociation energy, the energy eigenvalues of each energy level, and the profile of the wavefunctions in their correspondence vibrational states were presented in this paper. Calculation of the energy eigenvalues and plotting the wave function's profiles were performed using Numerov method combined with the shooting method. In general we concluded that the Morse potential solved with numerical methods could accurately produce the vibrational properties and the wavefunction behavior of BaO and SrO molecules from the ground state to the higher states close to the dissociation level. [ABSTRACT FROM AUTHOR]

The paper deals with synthesis and characterization of nanocrystalline Ba0.5Sr0.5Nb2O6 (BSN) and Co0.7Mg0.3Fe2O4 (MCFO) powders. The nanocomposites containing (1-X) BSN +XMCFO are prepared for X = 0.2, 0.3, 0.4, 0.5 and 0.6 and sintered at Ts = 1150 °C and 1225 °C. The composites are termed as 0.X MBSN. The paper reports the crystal structure, micro-structural analysis, dielectric constant, complex impedance spectroscopy and magnetoelectric properties of MBSN composites. It has been observed that the dielectric constant increases in the paraelectric region for lower frequencies due to the presence of interfacial polarization at the boundaries between BSN and ferrite phases. Here the complex impedance spectroscopy is carried out on the MBSN composites to determine various relaxation processes responsible for the observed dielectric behaviour. Further the dynamic magnetoelectric coefficient α is observed to increase with increasing Ts which is associated with increase in magneto-mechanical coupling for sintering at higher temperature. [ABSTRACT FROM AUTHOR]

Silver nanoparticle embedded 30BaO-20CaF2-50P2O5-4Ag2O-4SnO glasses were prepared by meltquenching and subsequent heat treatment process. Silver-doped glasses were heat treated at temperatures 500 °C, 525°C and 550 °C for a fixed duration of 10 hours to incorporate metal nanoparticles into the glass matrix. Appearance and shift in peak positions of the surface plasmon resonance (SPR) bands in the optical absorption spectra of heat treated glass samples indicated that both formation and growth of nanoparticle depended on heat treatment temperature. Glass sample heat treated at 525 °C showed a SPR peak around 3 eV, which indicated that spherical nanoparticles smaller than 20 nm were formed inside the glass matrix. Whereas sample heat treated at 550 °C showed a size dependent red shift in SPR peak due to the presence of silver nanoparticles of size larger than 20 nm. Size of the nanoparticles calculated using full-width at half-maximum (FWHM) of absorption band showed a good agreement with the particle size obtained from transmission electron microscopy (TEM) analysis. [ABSTRACT FROM AUTHOR]

The present study describes synthesis of Barium Oxide Nanoparticles decorated Multiwalled Carbon Nanotubes and its gas sensing behavior towards NH3 and CO gases. The decorated MWCNT sensor has an enhanced sensing towards NH3 gas compare to pure MWCNT sensor and also has much reduced response and recovery time. The prepared sensing material is characterized by TEM, XRD and Thermal Gravimetric analysis. [ABSTRACT FROM AUTHOR]

In this report, the nanocrystalline BaFe12O19 materials obtained by modified co-precipitation method using Na2CO3 and NaOH as precipitating agent are presented. In the modified co-precipitation process, instead of washing the co-precipitated product in mother liquor with de-ionized water, it was dried in a heating mantle, which has major influence as self flux in the single phase formation of BaFe12O19 phase. The co-precipitated product was annealed at 1000°C for 2 h under ambient pressure to obtain the required BaFe12O19 phase. The results based on XRD, average crystalline size, FT-IR, HR-SEM and EDX are reported. The annealed BaFe12O19 materials showed nanocrystalline single hexagonal phase with average crystalline size of ~102 nm. The annealed BaFe12O19 materials show particle sizes in the range of 280 ~326 nm and the thickness of ~57 nm in the high resolution micro-images. [ABSTRACT FROM AUTHOR]

Raman and Infrared spectroscopies have been employed to investigate the 25Bi2O3-(75-x)B2O3-xBaO glasses in order to obtain information about the competitive role of Bi2O3 and B2O3 in the formation of glass network. FTIR and Raman spectra show that these glasses are made up of [BO3], [BO4], [BiO3] pyramidal and [BiO6] octahedral units. [ABSTRACT FROM AUTHOR]

Glass samples with composition (35 - X) B2O3 - (40 + X) PbO - 25 TiO2 (where X = 0, 2.5, 5, 7.5 and 10 mol %) were prepared using conventional quenching technique. It was observed that as PbO content increases the value of Tcand Tc decreases. These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The density values of glass ceramic samples are higher than those of corresponding glass samples. It was observed that there was good correlation between the density and CTE results of the glass-ceramics. The XRD results revealed the formation of tetragonal lead titanate as a major crystalline phase in the glass ceramics. The dielectric constant of glass ceramic samples is higher than those of corresponding glasses [ABSTRACT FROM AUTHOR]

Here, we have performed strain induced structural, electronic and ferroelectric properties of BaReO3 by density functional theory (DFT) using first principles calculations. We noticed that band lines are shifted & the magnetic moment varies with applied strain on it. The changes are due to the majority contribution of Re-atom at the Fermi level while lesser contribution of O-atom in the valence band maximum (VBM). This means that in response to an applied mechanical load to the system, it is new way to approach the spintronic and memory devices. [ABSTRACT FROM AUTHOR]

Copper doped Ba0.97Ca0.03SO4 in its nanocrystalline form has been prepared and its thermo-luminescence (TL) properties are studied. The nanoparticles of the phosphor were prepared by the chemical co-precipitation method. The formation of the compound was confirmed by X-Ray Diffraction (XRD). The particle size was calculated by the broadening of the XRD peaks using Scherrer's formula. The TL glow curve of the phosphor has been found to have a simple structure with a single peak at 466 K. Compared to the higher molar concentration solution of Ba0.97Ca0.03SO4:Cu (0.3M), the nano-sized phosphor of lower molar concentration (0.2M and 0.1M) has a lesser TL sensitivity. However, this reduction in TL sensitivity on decreasing the particle size from higher molar concentration to lower molar concentration gives a better understanding of the TL phenomenon. The decrease in the sensitivity is attributed to the particle size effect i.e., the volume-to-surface ratio. [ABSTRACT FROM AUTHOR]

The characterization of spinel ferrite metamaterial towards microwave device applications is reported in this work. The spinel MgFe2O4 and Ba0.1Mg0.9Fe2O4 are prepared by molten salt method. The scattering parameters of the metamaterial are measured in the frequency range of 9 to 10 GHz by Nicolson-Ross method with Vector Network Analyzer. A negative permittivity between 9.219 to 9.345 GHz and a negative permeability between 9.703 to 9.901 GHz is observed. For the microwave device design, the 4πMs, Hres, and ΔH are measured from VSM and ferromagnetic resonance at 9.12 GHz respectively. [ABSTRACT FROM AUTHOR]