Transparent Al doped ZnO nanocrystalline films with a crystallite size less than 19 nm are obtained by spray pyrolysis. Band gap increases monotonically from 3.16 to 3.31 eV with increasing aluminum dopant up to 1.56 at.% facilitating increasing width of a transmission window in addition to the band gap tuning of 4.74% which compares favorably well with literature. UV emission with continuously increasing intensity is obtained which reflects on the good crystalline quality of the films. Also the defect emissions are suppressed remarkably as the dopant Al concentration increases in ZnO. The band gap tuning by quite small increment in dopant amount makes the present films, much attractive for the fabrication of light emitting devices with a much sought-for benefit of large area fabrication. FESEM shows the surface is granular with grain size lying in the range of 20–35 nm and EDX confirms the presence of Al in the doped samples.
In the present study, treatment of synthetic wastewater containing phenol, resorcinol and catechol was studied in a sequencing batch reactor (SBR). Parameters such as hydraulic retention time (HRT) and filling time have been optimized to increase the phenol, resorcinol, catechol and chemical oxygen demand (COD) removal efficiencies. More than 99% phenol, 95% resorcinol and 96% catechol and 89% COD removal efficiency was obtained at optimum conditions of HRT = 1.25 d and fill time = 1.5 h. The heating value of the sludge was found to be 12 MJ/kg. The sludge can be combusted to recover its energy value.
A wideband antenna with dual band characteristic at 5.33/14.3GHz with resonating frequencies for wireless applications is presented. The strategy of the design is to introduce multiband in antenna band. Bandwidth of the antenna increases by embedding annular ring on the radiating patch and four bands are achieved by introducing coupling gap between the patches. Surface current distribution is analyzed at different resonating frequencies for understanding the radiation mechanism and effect of annular ring. The antenna parameters such as return loss, radiation pattern, gain, VSWR and group delay are discussed. The impedance bandwidth of the proposed dual band antenna at lower resonant frequency is 12.7% (simulated) and 9.8 % (measured) whereas at upper resonant frequency is 15.3 % (simulated) and 13.97 % (measured).
In this paper, the problem of concentric pervious spheres carrying a fluid sink at their centre and rotating slowly with different uniform angular velocities Ω1. Ω2 about a diameter has been studied. The analysis reveals that only azimuthal component of velocity exists and the torque, rate of dissipated energy is found analytically in the present situation. The expression of torque on inner sphere rotating slowly with uniform angular velocity Ω1, while outer sphere also rotates slowly with uniform angular velocity Ω2, is evaluated. The special cases like, (i) inner sphere is fixed (i.e. Ω1 = 0), while outer sphere rotates with uniform angular velocity Ω2, (ii) outer sphere is fixed (i.e. Ω2 = 0), while inner sphere rotates with uniform angular velocity Ω1, (iii.) inner sphere rotates with uniform angular velocity Ω1, while outer rotates at infinity with angular velocity Ω2; have been deduced. The corresponding variation of torque with respect to sink parameter has been shown via figures. AMS subject classification – 76 D07.
In the present work TiO2 nanoparticles (NPs) have been dispersed into three different nematic liquid crystals (2020, 1823A and 1550C) in different concentration. The value of the birefringence (Δn) has been calculated by the transmitted intensity method at a 632.8 nm wavelength. NLC 2020 used in the present study is a high birefringent material (Δn = 0.44), NLC 1550C is a low birefringent material (Δn = 0.067) and NLC 1823A is a mid birefringent material (Δn = 0.14). An increased value of birefringence has been found after dispersion of TiO2 NPs in all three NLCs but this increment depends upon the concentration of the dopant material, temperature range and chemical character of the mixtures. It is suggested that this LC materials can be applicable in making of phase shifters, compensators and many more photonic devices.
In the present investigation optical, electro-optical and dielectric properties have been measured for nematic liquid crystal (NLC) material 1550C which consists of 4’-(trans, trans-4-alkylbicyclohexyl) carbonates and 4’-(4-(trans,trans-4-alkyl)-4-cyanobicyclohexane, dispersed with fluorescent dye (Benzo 2,1,3 Thiadiazole) in two different concentrations. Photoluminescence has been enhanced for a dye dispersed system which is the key finding of this investigation. UV absorbance study has also been performed and found to be increased for composite system. Enhanced birefringence after dispersion of dye into pure NLC is also a prominent result of this investigation. Relative permittivity, threshold voltage and dielectric anisotropy have also been measured and found to be increased. The outcome of the present work may be very useful in the construction of liquid crystal displays (LCDs).
Barley phylloplane is seriously colonized by Drechslera graminea, the causal agent of leaf
stripe disease in the hos. The present study involved the elucidation of alterations induced
in the protein content of the host due to Drechslera infection. Naturally growing barley
plants were obtained from fields and Drechslera graminea was isolated and identified from
diseased plants’ leaves. After identification and preparation of the pure culture, the pathogen
was inoculated on plants grown under aseptic and controlled laboratory conditions.
Changes in the total soluble cytoplasmic proteins and defense enzymes of the host such
as polyphenol oxidase (PPO), peroxidase (POX), phenylalanine lyase (PAL) and tyrosine
ammonia lyase (TAL) were observed up to 5 h after inoculation. The results demonstrated
a significant effect of the pathogen on the cytoplasmic protein expression of the host as well
as in its defense system.