Mechanochemical synthesis of PbS/Ni–Cr layered double hydroxide nanocomposite

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Investigation of the structural properties of annealed CdIn2Te4/CdS thin film solar cells produced by the electron-beam evaporation (e-beam) technique

Thin film CdIn₂Te₄/CdS solar cells were deposited onto the ITO-coated glass substrate by electron beam evaporation (e-beam) technique, and the the effect of annealing on their structural properties is studied. The annealing was performed under nitrogen atmosphere for 1 h. The manufactured solar cells were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDAX) analysis. Crystallite size (D), inter-planer distance (d) and lattice constant (a) values were calculated for the thin film solar cell from XRD data. Annealed samples display well defined XRD patterns with three diffraction peaks. We observed increased peak intensity in the annealed films. EDAX analysis showed that only CdIn₂Te₄ is present in absorber layer and CdS is found in the window layer, but no impurity atoms are present the structure. It is observed that surface roughness of the annealed films incresed, according to SEM images. The I–V characteristics show that the current is increased for annealed thin films solar cells.

     

Energetic materials: The preparation and structural characterization of melaminium dinitramide and melaminium nitrate

Two energetic salts of the melaminium cation have been prepared and structurally characterized from room temperature X-ray single crystal diffraction data. Melaminium dinitramide (I), triclinic, P1¯, a = 6.6861(11), b = 6.9638(16), c = 10.447(2) Å , = 99.07(3), = 98.30(3), = 108.50(3)°, V = 445.6(2) ų, and Z = 2. Melaminium nitrate (II), monoclinic, P2₁/c, a = 3.5789(7), b = 20.466(4), c = 10.060(2) Å, = 94.01(2)°, V = 735.0(3) ų, and Z = 4. The crystal structures of both salts show distinct monoprotonated melaminium cations and dinitramide- or nitrate anions, respectively. Efficient packing in the solid state is achieved by extensive hydrogen bonding between two-dimensional zigzag ribbons of the melaminium cations and the respective anions resulting in high densities of the solid state structures of 1.74 (I) and 1.71 g/cm³ (II).     

Concurrence and Negativity as a Family of Two Measures Elaborated for Pure Qudit States

We investigate entangled states of an atomic trapped ion interacting with two phonons in the Λ configuration forming a twelve-dimensional Hilbert space. We study two elaborated measures, namely, the concurrence C and negativity N, which are important in current theoretical studies. Therefore, we work with the three-dimensional reduced density matrix in calculating the measures elaborated for pure qudit states in the ionic–phononic system. To demonstrate the benefits of the family of the two measures elaborated, we perform the calculations for different values of the Lamb–Dicke (LD) parameter η = 0.01, 0.3, and 0.5. Finally, we show that the pure qudit states under study are maximum entangled states.     

Full-trapped three-level ion in the lamb–dicke limit: analyzing and comparing quantum entanglement measures of two qudits

Our aim is to investigate the entanglement dynamics and quantum correlations of a full-trapped ion interacting with two time-independent laser beams in view of the Lamb–Dicke parameter. For this purpose, the three probability amplitudes in the trapped ion is taken as ?{1

Higher dimensional entangled qudits in a trapped three-level ion

Quantum entangled states in a system of trapped three-level ion interacting with two laser beams in Λ (Lambda) configuration is investigated. We have characterized a typical family of initial conditions for their potential to generate quantum entanglement of internal and external degrees of freedom of the ion. It is found that entangled qudits, specifially qutrits and quadrits, can be optimally for a certain preparation of the ionic system. Analytical results, describing the quantum entangled state explicity, are presented. The amount of quantum entanglement is quantified directly by calculating the generalized concurrence for arbitrary qudits. It is obtained that higher dimensional entanglement can be established with the Lamb-Dicke parameter (LDP). The LDP dependence of Schmidt coefficients is shown.     

A comparison of genetic programming and neural networks; new formulations for electrical resistivity of Zn–Fe alloys

It is difficult to automatically solve a problem in a systematic method without using computers. In this study, a comparison between Neural Network (NN) and genetic programming (GEP) soft computing techniques as alternative tools for the formulation of electrical resistivity of zinc–iron (Zn–Fe) alloys for various compositions is proposed. Different formulations are supplied to control the verity and robustness of NN and GEP for the formulation to design composition and electrolyte conditions in certain ranges. The input parameters of the NN and GEP models are weight percentages of zinc and iron in the film and in the electrolyte, measurement temperature, and corrosion voltage of the films. The NN- and GEP-based formulation results are compared with experimental results and found to be quite reliable with a very high correlation (R ²=0.998 for GEP and 0.999 for NN).     

Cellulose nanocrystals as promising adsorbents for the removal of cationic dyes

Cellulose nanocrystals (CNCs) prepared from cellulose fibre via sulfuric acid hydrolysis was used as an adsorbent for the removal of methylene blue (MB) from aqueous solution. The effects of pH, adsorbent dosage, temperature, ionic strength, initial dye concentration were studied to optimize the conditions for the maximum adsorption of dye. Adsorption equilibrium data was fitted to both Langmuir and Freundlich isotherm models, where the Langmuir model better described the adsorption process. The maximum adsorption capacity was 118 mg dye/g CNC at 25 °C and pH 9. Calculated thermodynamic parameters, such as free energy change (ΔG = ?20.8 kJ/mol), enthalpy change (ΔH = ?3.45 kJ/mol), and entropy change (ΔS = 0.58 kJ/mol K) indicates that MB adsorption on CNCs is a spontaneous exothermic process. Tunability of the adsorption capacity by surface modification of CNCs was shown by oxidizing the primary hydroxyl groups on the CNC surface with TEMPO reagent and the adsorption capacity was increased from 118 to 769 mg dye/g CNC.     

Genetic programming modelling for the electrical resistivity of Cu–Zn thin films

Using quantum hydrodynamic (QHD) model and standard reductive perturbation method, we have investigated the formation and characteristics of space-charge solitary waves and double layers in n-type compensated drifting semiconductor plasma with varying doping profiles. Through numerical analysis, it is shown that the structures of space-charge solitary waves and double layers depend significantly on electron drift and compensation parameter which measures a comparative proportion of the donor, acceptor and intrinsic ion concentrations.