Modern Physics Letters B

Usually complicated unitary operators in exponential form are hard to handle and the transformation stated by them are not physically clear until these operators are disentangled. By virtue of the technique of integration within an ordered product (IWOP) of operators, we can disentangle some complicated unitary operators and then reveal their physical role. Many new unitary operators can be found after new quantum mechanical representations are constructed by virtue of the IWOP technique. The unitary operators for permutation, Hilbert transform, Householder transform, and Hardmad transform can also be introduced. The IWOP technique thus bridges this mathematical gap between classical mechanics and quantum mechanics and provides a new route connecting classical transformations to quantum mechanical unitary operators. In this way, the symbolic method exhibits further beauty and elegance and can be increasingly used for developing various fields of quantum physics.

We report studies of the formation of ordered microporous polymer films by the evaporation of polymer solutions following exposure to a humid atmosphere. High-speed microphotographic (HSMP) studies of the formation process reveal that near the surface of the polymer solution, vapor condensation produces near monodisperse water droplets which crystallize to form a close-packed array. Following the evaporation of the solvent, characterization of the solid by Atomic Force Microscopy, confocal microscopy and white light interferometry reveals that the surface of the polymer film features extensive regions of hexagonally close-packed microscopic pores, whose spatial arrangement replicates that of the initial droplet monolayer. Defects recorded by HSMP in the packing of the colloidal monolayer of liquid droplets formed above the surface of the polymer solution are found to correspond to those transferred into the eventual solid film, providing the first direct evidence of the structure templating role of the droplet monolayer.

Nowadays, the pacific use of ionizing radiation has attracted a great deal of attention in medicine, as well as in radiodiagnostic, and radiotherapy. However to avoid unnecessary irradiations to the healthy tissue, a strict quality control is required. This has led to the development of a new dosimeter equivalent to the tissue that could be highly suitable for the radiation dosimetry. The borate of magnesium with its low effective atomic number (Z_eff), is considered equivalent to the human-tissue. For this reason, in this work, we present the results obtained of the thermoluminescent characterization of this material. The test that was carried out includes the lower detection limit, sensitivity, reproducibility of the TL measurement, stability of information (fading), and TL response as a function of the delivered dose and energy response, which are recommended by the International Commission on Radiological Units and Measurements (ICRU) and International Commission on Radiological Protection (ICRP). Two different concentrations of Dy activator were used i.e. 1.25 (batch A) and 1.5 (batch B) mol%. Meanwhile, the Na activator was 0.5 mol% in both cases. The results show that this new thermoluminescent material is adequate for radiation dosimetry in different medical applications.

A hierarchy of discrete lattice soliton equation is obtained by using a novel algebraic system, and its Hamiltonian structure is generated by use of the Tu model. Then, conservation laws and integrable coupling of the obtained equation hierarchies are discussed.

In view of the analysis on the characteristics of the generalized Burgers equation, generalized KdV equation and generalized Burgers–KdV equation, a combination method is presented to seek the explicit and exact solutions to the generalized Burgers–KdV equation by combining with those of the generalized Burgers equation and generalized KdV equation. As a result, many explicit and exact solutions for the generalized Burgers–KdV equation are successfully obtained by this technique.

Sm-doped Li–Ni ferrites were synthesized by a soft chemistry method. The effects of Sm-doping on the structural and magnetic properties of the Li–Ni ferrites were investigated. The structural, morphological and magnetic properties of the ferrite samples were characterized by X-ray diffractometer (XRD), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). The results revealed that the Sm-doped samples had the single spinel phase at low Sm content. The increase in Sm content increased the lattice parameter and decreased the particle sizes. The magnetic properties of the Sm-doped Li–Ni ferrites were strongly affected by Sm content. The saturation magnetization decreased, while coercivity increased with increasing Sm content.

Single crystals of a new semi-organic nonlinear optical material glycine hydrobromide were grown from solution by slow evaporation at room temperature. Good optical quality single crystals with dimensions 17×8×5 mm³ were obtained. The grown crystal had been confirmed by single-crystal X-ray diffraction and the vibrational frequencies of various functional groups in the crystals had been derived from Fourier transform infrared spectrum. The optical quality of the grown crystals was analyzed by the Ultraviolet visible spectrum method. The mechanical behavior of the grown crystal was evaluated by Vickers' micro-hardness indentation method. The nonlinear optical property of the crystal was confirmed by the Kurtz powder technique using Nd:YAG laser as a source.