Effect of Li2CO3 on formation temperature of hBN by modified O'Connor model

This study is interested in the effect of lithium carbonate on the formation of hexagonal boron nitride (hBN) by means of the available experimental methods including TGA, XRD, FTIR, SEM and HR‐TEM. hBN samples were synthesized at the 1450 °C with different molar ratios of lithium carbonate by modified O'Connor routine. The crystalline hBN formation tended to improve with the increment of the Li₂CO₃ concentration level (especially after more 20 %). The dopant quantity decreased the residual stresses due to the presence of possible relaxation mechanisms along with the nanocrystal structure, even favored by XRD experimental findings regarding the enhancement of crystal plane alignments, crystallite sizes and lattice parameters. As for the FTIR surveys, the Li₂CO₃ foreign impurities strengthened more and more the covalent bonds between boron and nitrogen atoms. At the same time, the samples with 40 % lithium carbonate were annealed at the varied temperatures of 1000, 1150, 1300 and 1450 °C to determine the optimum annealing temperature. The XRD+FTIR investigations indicated that the degree of hexagonality improved with the increased annealing temperature. Similarly, the surface morphology confirmed not only the formation of regularity and flaky hexagonal BN structures, but also the strengthening of covalent bonds between the atoms.     

Canonical structure of the CP sigma model in 1 + 2 dimensions

The CP^N model with a θ-term in 1 + 2 dimensions is quantized canonically. By employing a suitable parametrization we demonstrate that solitons carry θ-dependent fractional spins.     

A perturbative QCD estimate of the η1-Mass

Using perturbative QCD expansions for the two-point correlation function of the U_A(1) current in a properly constructed dispersion sum rule, and using a previously obtained estimate for the strange quark mass, we obtain a realistic upper bound on the η₁-mass.     

Axial anomaly and chiral symmetry breaking in Schwinger model: A canonical approach

We use a recently introduced canonical surface formalism, to study the problem of chiral symmetry breaking in the Schwinger model. We perfect the parallel between QCD₄ and QED₂ in this respect.     

Gauged Goldstone boson effective action from direct integration of bardeen anomaly

We derive the effective action which describes the anomalous Goldstone boson interactions in the presence of external flavour SU(N)_L×SU(N)_R gauge fields, by a direct integration of the Bardeen anomaly. Through comparison with other results, we are able to elucidate the relationship between anomalies based on different regularization schemes. We also give a compact representation of the anomalous part of the fermionic determinant allowing for a simpler rederivation of our results.     

Quantum‐chemical,IR, NMR,and X‐ray diffraction studies on 2‐(4‐chlorophenyl)‐1‐methyl‐ 1H‐benzo[d]imidazole

The title molecule, 2‐(4‐chlorophenyl)‐1‐methyl‐1H‐benzo[d]imidazole (C₁₄H₁₁ClN₂), was prepared and characterized by ¹H NMR, ¹³C NMR, IR, and single‐crystal X‐ray diffraction. The molecular geometry, vibrational frequencies, and gauge including atomic orbital (GIAO) ¹H and ¹³C NMR chemical shift values of the title compound in the ground state have been calculated by using the Hartree‐Fock (HF) and density functional theory (DFT/B3LYP) method with 6‐31G(d) basis sets, and compared with the experimental data. The calculated results show that the optimized geometries can well reproduce the crystal structural parameters, and the theoretical vibrational frequencies and GIAO ¹H and ¹³C NMR chemical shifts show good agreement with experimental values. The energetic behavior of the title compound in solvent media has been examined using B3LYP method with the 6‐31G(d) basis set by applying the Onsager and the polarizable continuum model (PCM). Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis, and nonlinear optical (NLO) properties of the title compound were investigated by theoretical calculations. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Conformational Dynamics of Poly(acrylic acid)-Bovine Serum Albumin Polycomplexes at Different pH Conditions

This work presents the real time surface plasmon resonance (SPR) and fluorescence spectroscopy observation of cooperative interactions between aggregate-forming bovine serum albumin (BSA) and oppositely charged linear macromolecule poly(acrylic) acid (PAA). Interactions between protein and polymer result in formation of polyelectrolyte-protein polycomplexes, which exhibit expressed conformational transformations, especially at low pH. The rate constants of observed kinetic transformations were calculated and found to vary in the range from 0.8 × 10⁻³ to 6.7 × 10⁻³ for different pH values. The processes of aggregation, sedimentation and conformation of BSA-PAA complex are discussed.     

On the topological equivalence of gauge and Higgs fields in the dyon sectors

We prove by topological methods methods that in the context of SU(2) gauge theory the integers labelling the homotopy classes of Yang-Mills and Higgs fields are equal for periodic instanton and dyon configurations. A similar statement is true for the group SO(3) and, in the periodic instanton case, whenever a simply connected group is broken down to an abelian subgroup. We briefly discuss how the result goes over to the canonically quantized theory.