Ab initio investigation of the electronic and vibrational properties for the (CaLi)+ ionic molecule

A wide adiabatic study has been performed for numerous electronic states of CaLi⁺ molecular ion. The adiabatic potential energy curves and their spectroscopic constants (R_e, D_e, ω_e and T_e) have been calculated using an ab initio approach including a nonempirical pseudo-potential for the Ca and Li cores with the core polarisation potentials operator through full configuration interaction (FCI). Thereafter, the energies of vibrational levels and their spacing for all these states have been reported. In addition, the electric dipole moment curves have been investigated for the (1-19) Σ, (1-12) Π and (1-8) Δ electric states. Moreover it lets us check the extreme transition dipole moments (TDM). These behaviours of TDM are more accustomed to estimate the radiative lifetimes for all vibrational levels in 2¹Σ⁺ and 3¹Σ⁺ states. Also, the bound-bound and the bound-free contribution have been calculated precisely and by employing a Franck–Condon (FC) approximation.     

Insight into lattice thermal impedance via equilibrium molecular dynamics: case study on Al

Using results of equilibrium molecular dynamics simulation in conjunction with the Green–Kubo formalism, we present a general treatment of thermal impedance of a crystal lattice with a monatomic unit cell. The treatment is based on an analytical expression for the heat current autocorrelation function which reveals, in a monatomic lattice, an energy gap between the origin of the phonon states and the beginning of the energy spectrum of the so-called acoustic short-range phonon modes. Although, we consider here the f.c.c. Al model as a case example, the analytical expression is shown to be consistent for different models of elemental f.c.c. crystals over a wide temperature range. Furthermore, we predict a frequency ‘window’ where the thermal waves can be generated in a monatomic lattice by an external periodic temperature perturbation.     

MgO(001) barrier based magnetic tunnel junctions and their device applications

Spintronics has received a great attention and significant interest within the past decades,and provided considerable and remarked applications in industry and electronic information etc.In spintronics,the MgO based magnetic tunnel junction(MTJ) is an important research advancement because of its physical properties and excellent performance,such as the high TMR ratio in MgO based MTJs.We present an overview of more than a decade development in MgO based MTJs.The review contains three main sections.(1) Research of several types of MgO based MTJs,including single-crystal MgO barrier based-MTJs,double barrier MTJs,MgO based MTJs with interlayer,novel electrode material MTJs based on MgO,novel barrier based MTJs,novel barrier MTJs based on MgO,and perpendicular MTJs.(2) Some typical physical effects in MgO based MTJs,which include six observed physical effects in MgO based MTJs,namely spin transfer torque(STT) effect,Coulomb blockade magnetoresistance(CBMR) effect,oscillatory magnetoresistance,quantum-well resonance tunneling effect,electric field assisted magnetization switching effect,and spincaloric effect.(3) In the last section,a brief introduction of some important device applications of MgO based MTJs,such as GMR & TMR read heads and magneto-sensitive sensors,both field and current switching MRAM,spin nano oscillators,and spin logic devices,have been provided.     

Thermodynamic Study of the Extraction of Inorganic Mercury Compounds in Fish Species of the International Anzali Wetland,Iran

Inorganic mercury concentration was measured in the muscle tissues of four types of fish in the aquatic international Anzali Wetland ecosystem in Guilan. In the same ecosystem, the northern pike is able to concentrate inorganic mercury in its body more than other fish. In each species, a fish with the highest amount of inorganic mercury was selected for determination of thermodynamic parameters of inorganic mercury extraction using calculation of the equilibrium constant and fitting of ln K_c versus inverse temperature at the atmospheric pressure. The origins of thermodynamic parameters were discussed. The extraction processes were done in the range of temperatures from 331.15 to 365.15 K and at atmospheric pressure. Results show that the extraction of mercury compounds from SH groups of sulfhydryl proteins in fish muscle tissue is an endothermic process with a positive value for entropy and Gibbs free energy changes at room temperature.     

Combination of Dispersive Liquid‐Liquid Microextraction with Flame Atomic Absorption for Determination of Trace Ni and Co in Water Samples and Vitamin B12

A dispersive liquid‐liquid microextraction method based on the dispersion of 1,2‐dichlorobenzene as an extraction solvent into an aqueous phase in the presence of ethanol as a dispersive solvent for the preconcentration of Co²⁺ and Ni²⁺ ions is discussed. 1‐Nitroso 2‐naphtol was used as a chelating agent prior to the extraction and the preconcentrated analyte was determined by flame atomic absorption spectrometry. The effect of various experimental parameters including the extraction and dispersive solvent type and volume, pH, amount of the chelating agent, etc. on the microextraction and complex formation was investigated for finding the optimum conditions. The enhancement factors were about 61.9 and 51.8, the calibration graphs were linear in the range of 10‐150 μgL^?1 and 10‐250 μgL^?1 with detection limits of 2.42 μgL^?1 and 1.59 μgL^?1, and RSD (n = 5) of 3.08% and 2.17% for cobalt and nickel, respectively. The method was successfully applied to the determination of Co and Ni in water and vitamin B₁₂.     

Nuclear signatures in high-order harmonic generation from laser-driven muonic atoms

High-order harmonic generation from muonic atoms exposed to intense laser fields is considered. Our particular interest lies in effects arising from the finite nuclear mass and size. We numerically perform a fully quantum mechanical treatment of the muon-nucleus dynamics by employing modified soft-core and hard-core potentials. It is shown that the position of the high-energy cutoff of the harmonic spectrum depends on the nuclear mass, while the height of the spectral plateau is sensitive to the nuclear radius. We also demonstrate that gamma-ray harmonics can be generated from muonic atoms in ultrastrong VUV fields, which have potential to induce photonuclear reactions.     

Microwave‐Assisted Catalyst Free Three Component Synthesis of Mono and Bis Spiro Pyrazolopyridines in Solvent Free Reaction

Multicomponent synthesis of mono and bis‐spiro pyrazolopyridines from isatin derivatives, indanedione, and 3‐methyl‐5‐aminopyrazole under microwave irradiation in the absence of any catalyst or solvent with high yield and short reaction time is reported.     

On the theta completions for maximal subalgebras

Let L be a finite dimensional Lie algebra. Then for a maximal subalgebra M of L, a 𝜃-completion for M is a subalgebra C of L such that CM and M_L?C and C∕M_L contains no non-zero ideal of L∕M_L, properly. And a 𝜃-completion C of M is said to be a strong 𝜃-completion, if C = L or there exists a subalgebra B of L such that C be maximal in B and B is not a 𝜃-completion for M. These are analogous to the concepts of 𝜃-completion and strong 𝜃-completion of a maximal subgroup of a finite group. Now, we consider the influence of these concepts on the structure of a finite dimensional Lie algebra.