Journal of Interface, Thin Film and Low Dimension Systems
Volume:1 Issue: 1, Summer-Autumn 2017

X-ray diffraction (XRD) technique due to it's strength for providing visualized atomic model of molecules, stands as first in the field of characterization of new synthesized molecules. Here, the analysis of diffraction data on discrete units of new, not yet fairly known structure of molecule $rm C_{52} H_{60} N_4 S_8 Zn_2$ is performed to obtain a quantitative view of the structure of the system. Some note about the layer shape of the moleucle is mentioned. First, a qualitative discussion of the type of intra-molecular order is given. Then, the nano-particle's size definitions, via different approaches of coherence, correlation, etc are addressed. Each of the different defined values is obtained and difference between them and their interpretation will be discussed. Debye function analysis (DFA) is employed to approximate the radius of gyration, as another approach for estimating particle's size. Results of different defined values, the radius of gyration, approximate coherence length are estimated and decision on the size of molecule is made. These analyses will provide us some neat picture of different definitions of size of nano-systems, which lacks clearance in the literature.

In this article we investigate the behaviour of the scaling exponentsof KPZ equation through changing three parameters of the equation. Inother words we would like to know how the growth exponent β and theroughness exponent α will change if the surface tension ν , the averagevelocity λ and the noise strength γchange. Using the discrete form of theequation , first we come to the results α = 0.5 and β = 0.33 , then wechange the parameters in the range of 0 to 3 by small amounts , we observethat the exponents change smoothly. In some limit states KPZ equationtransforms to RD and RDSR equations. Fortunately this is obvious inthe figures. As the parameters change and approach the limit states, theKPZ universality class evolves to RD and RDSR regimes.

The realization that entanglement can affect macroscopic properties of bulk solid-state systems is a challenge in physics and Chemistry. Theoretical physicists often are considered the entanglement between nearest-neighbor (NN) spins and tried to find its characterizations in terms of macroscopic thermodynamics observables as magnetization and specific heat. Here, we focus on the entanglement between next nearest neighbor (NNN) and the next to next nearest neighbor (NNNN) spins in an exactly solvable model. We show that there is a much clearer fingerprint of the longer-distance entanglement on the thermodynamic properties like the specific heat, the magnetocaloric effect and the magnetic susceptibility.

Poly (ether) urethane close/open cell (PEUCC/PEUOC) has been prepared by using in situ polymerization approach. The third-order optical nonlinearities of dissolved samples in DMF were characterized by Z-scan technique at the measurement wavelength of 532 nm. The synthesized samples were also examined by optical microscopy and UV-Vis absorption spectroscopy. The nonlinear refractive (NLR) indices of the synthesized samples were obtained in the order of 10-10(cm2/W) with negative sign. By focusing on the collected UV-Vis absorption spectra of PEUCC/PEUOC, it was found that the red shift in the absorption edge of the samples is larger in the case of PEUCC that in the PEUOC. It was revealed that introducing some materials into polyurethane (PU) spatially PEUCC could increase nonlinearity that they can be considered as a promising candidate for the application to optical limiting in the visible region.

In this work structural defects were created in P25-TiO2 nanoparticles by using hydrogen DC plasma treatment in different temperatures and exposure times. X-Ray diffraction measurements show that the structure of TiO2 remains unchanged after hydrogenation. Diffuse reflectance spectroscopy measurements demonstrated band gap of TiO2 was not changed considerably by the hydrogenation. However, by applying the hydrogen plasma for 40 min at temperature of 350 °C photocatalytic activity of TiO2 nanoparticles enhances. No more change was observed in the photocatalytic activity of the samples with plasma exposure time more than 40 min. Photoluminescence analysis shows the sample prepared at 350 °C has a large amount of defects which have been created by the plasma treatment. It seems both, structural defects and hydrogen doping in the samples are important for more efficient photocatalytic behavior of TiO2 nanoparticles.

Based on quantum hydrodynamics theory (QHD), the propagation of nonlinear quantum dust-ion acoustic (QDIA) solitary waves in a ‎collision-less, unmagnetized four component quantum plasma consisting of electrons, positrons, ions and stationary negatively charged ‎dust grains with dust charge variation is investigated using reductive perturbation method. The charging current to the dust grains carried ‎by the plasma particle, has been calculated with the orbit-limited motion approach. The quantum current of electrons and positrons is ‎obtained by using Fermi-distribution functions. The basic features of QDIA solitary waves are studied by deriving the Korteweg-de Vries ‎‎(KdV) Equation. It is found that both rarefactive and compressive type of solitons can exist in the model plasma. Further, the nonlinear ‎and dispersive coefficients in KdV equation are modified by consideration dust charge variation effect and Fermi-Dirac distribution ‎function. The present investigations should be useful for researches on astrophysical plasmas as well as for ultra small micro- and nano- ‎electronic devices.‎