Characterization of dip-coated ITO films derived from nanoparticles synthesized by␣low-pressure spray pyrolysis

In₂O₃:Sn (Indium Tin Oxide; ITO) films were prepared from a sol solution with highly crystalline ITO nanoparticles (less than 20 nm in size with 10 at.% Sn) which had been prepared by low-pressure spray pyrolysis (LPSP) in a single step. The ITO sol solution was prepared by dispersing LPSP-prepared ITO nanoparticles into ultra pure water. The nanoparticle ITO film was deposited on a glass substrate using a dip-coating method and then annealed in air at various temperatures. The optical transmittances of the ITO films were measured by UV–Vis spectrometry, and the films were found to have a high transparency to visible light (in the case of a film thickness of 250 nm annealed at 400°C, the transparency was in excess of 95% over the range λ=450–800 nm, with a maximum value near 100% at wavelengths above λ=700 nm). The optical transmittances of the films were influenced by the size of the ITO particle used, the film thickness and the annealing temperature. The ITO films showed a minimum resistivity of 9.5×10⁻² Ω cm, and their resistivity was affected by both the ITO particle size and the annealing temperature used.     

Functional Nanostructured Silica Powders Derived from Colloidal Suspensions by Sol Spraying

The preparation of silica powders derived from sols with a variety of primary particle sizes from 4 to 100 nm and the influences of preparation conditions such as drying temperature and initial concentration of precursor on the final powders morphology were investigated for the first time. The prepared silica powders have spherical morphology, and the final diameter (between 0.1 and 2 um) was controlled by changing the concentration of starting colloidal suspension. The preparation of silica based luminescent powders was investigated by adding europium ion as the dopant. The Eu-doped silica powders showed a visible-luminescence with wavelength of 613 nm, a red emission, under excitation of 394 nm light source. The effects of Eu-doping concentration, operation temperature and primary particle size of silica sols on the luminescence were also investigated.     

Crystal structure and thermal expansion of N,N,N′,N′-tetrakis-[(1H,2,4-triazol-1-yl)methyl]-ethane-1,2-diamine

Structural Chemistry - The crystal structure of N,N,N′,N′-tetrakis-[(1H,2,4-triazol-1-yl)methyl]-ethane-1,2-diamine has been fully determined at six different temperatures by X-ray...     

Quantum cutting effect and photoluminescence emission at about 1,000 nm from Er–Yb co-doped ZnO nanoplates prepared by wet chemical precipitation method

ZnO nanoplates with Er-doping concentrations varying in the range from 3 to 7 wt% and co-doped with (Er–Yb) (7 + 7 wt%) were successfully prepared by wet chemical precipitation method. The effects of doping on the structural and optical properties of ZnO nanostructures have been systematically investigated. The structural morphology of the prepared nanostructures was found to change with increasing Er-doping concentrations. The visible photoluminescence and infrared photoluminescence of the prepared nanostructures were measured at room temperature. The intensity of visible emission spectra was found to increase with increasing Er-doping concentrations and was further enhanced for (Er–Yb) co-doped ZnO nanoplate samples. Additionally, Er-doped (7 wt%) and Yb-doped (7 wt%) ZnO nanoplates showed an enhanced emission peak at 950 nm, whereas two enhanced emission peaks at 950 and 980 nm have been found for (Er–Yb)-co-doped (7 + 7 wt%) ZnO nanoplates samples when excited at 310, 365 and 371 nm excitation wavelengths.     

Neutral current interactions based on the gauge group SU(2)L × (T3)R × UV(1)

We present a unified model based on the gauge group SU(2)_L × (T₃)_R × U_V(1) which successfully reproduces all the neutrino and electron-deuterium scattering data, the y-dependence of the latter, and still permits a range of values for Q_W measured in atomic physics.     

Products from metallation and attempted metallation of 1-alkyl-4,6-diphenyl-2-pyridones and subsequent reaction with electrophiles

The title pyridones form products in which either their own carbanion, or an alkylcarbanion, has added to the 3-position, followed by an electrophile to the 4-position.     

Some numerical experiments on the splitting of Burgers' equation

The combined approach of linearization and splitting up is used for devising new algorithms to solve a one-dimensional Burgers' equation. Two schemes are discussed and the computed solutions are compared with the exact solution. For this problem it is found that the schemes proposed yield excellent numerical results for Reynolds number R ranges from 50 up to 1500. The schemes were also tested for another problem whose R = 10000. In this case a filtering technique is used to overcome the nonlinear instability.     

Numerical solutions of the improved Boussinesq equation

The combined approach of linearisation and finite difference method is used to solve the improved Boussinesq equation. A three-level iterative scheme having second order accuracy and constant coefficients matrix is devised and used in discussing the dynamics of waves having various initial wave packets. The results are in good agreement with the available results.     

The First Quantization of Spin \frac32\frac{3}{2} Field in de Sitter Space

The de Sitter solution to the positive cosmological Einstein field equation has been viewed as a one-sheeted hyperboloid embedded in a five dimensional Minkowski space. To find Lagrangian equation of supersymmetry-group in the de Sitter space, the different spinor field’s quantization have been demonstrated. In this work, the first quantization of spin field in the time-space de Sitter universe with ambient space notation has been done.     

Quadratic electro-optic effect and electro-absorption process in CdSe-ZnS-CdSe structure

The third order nonlinearity susceptibility is obtained as a function of wavelength for CdSe-ZnS-CdSe structure. Numerical calculations show that the quadratic electro-optic and electro absorption effects of this structure depend on the parameters such as structure size, relaxation time and pump photon energy. By changing shells thickness, these structures can be designed with the susceptibility peak from the visible to infrared regions of the spectrum. The intensity and position of the third order nonlinearity susceptibility peaks depend on outer shell thickness and radius of the core.