On a q-gamma and a q-beta matrix functions

The main goal of this article is to extend the concept of q-special functions of complex variable to q-special matrix functions through the study of a q-gamma and a q-beta matrix function. The q-shifted factorial, q-gamma and q-beta matrix functions are defined and some of their properties are investigated.     

Recent synthetic methodologies for pyrazolo[1,5-a]pyrimidine

The development of new synthetic routes towards pyrazolo[1,5-a]pyrimidines for their biological and medicinal exploration is an attractive area for researchers. This review focuses on various synthetic routes developed in the last decade for the synthesis of differently substituted pyrazolo[1,5-a]pyrimidines by a broad range of organic reactions by means of 5-aminopyrazole as a precursor.     

Coherence-induced polarization changes in light beams

We consider a class of stochastic electromagnetic beams, and we show both analytically and by numerical examples that coherence properties of the electromagnetic field in the source plane affect the polarization properties of the radiated beam.     

The turbulent Alfvénic aurora

It is demonstrated from observations that the Alfvénic aurora may be powered by a turbulent cascade transverse to the geomagnetic field from large MHD scales to small Alfvén wave scales of several electron skin depths and less. We show that the energy transport through the cascade is sufficient to drive the observed acceleration of electrons from near-Earth space to form the aurora. We find that regions of Alfvén wave dissipation, and particle acceleration, are localized or intermittent and embedded within a near-homogeneous background of large-scale MHD structures.     

An overview on synthetic strategies to coumarins

Coumarins units have recently emerged as a hot topic of research due to their diverse applications. Their synthesis is partly based on classical methodologies such as Pechmann reaction or Knoevenagel condensation, but it also sparked the discovery of completely new pathways. In very recent years so-called vertically expanded coumarins were synthesized, effectively expanding the portfolio of existing architectures. This review serves as a guide through synthesis strategies to coumarins.     

Study of the region of glass formation and electrical properties of the AsSeSb system

Glassy samples containing As, Se and Sb in different ratios are synthesized under a vacuum of the order of 10^?5 Torr and at a temperature of (950 ± 20)°C. The region of glass formation of this system is determined. It is found that antimony can be added in amounts of up to approximately 19 at.% in As₂Se₃ while the glassy state is still preserved. Thermal activation energy for the samples is found to decrease with the increase of antimony content. The conductivity at 20°C and the logarithmic value of the constant σ₀ are determined for each composition investigated. Annealing of the samples (induces crystallization) reduces both thermal activation energy and room temperature resistivity. Preliminary devitrification characteristics of some samples in this system using X-ray and differential thermal analysis are given.     

A new pd-catalyzed cascade reaction for the synthesis of strained aromatic polycycles

Two new palladium catalyzed cascade reactions involving a 4-exo-dig cyclocarbopalladation are described. These processes are shown to convert bromoenediynes and bromodienynes into strained aromatic compounds in a single step.     

Metal complexes derived from hydrazoneoxime ligands: IV. Molecular and supramolecular structures of some nickel(II) complexes derived from diacetylmonoxime S-benzyldithiocarbazonate

Four new nickel(II) complexes, [{Ni(L)}₂], [NiL · HPyr], [NiL · HIm] and [Ni(HL)₂] · H₂O, derived from diacetylmonoxime-S-benzyldithiocarbazonate (H₂L) have been synthesized and characterized by elemental analyses, field desorption and electrospray ionization mass spectra, UV–Vis, infrared absorption spectra, as well as ¹H NMR spectra. X-ray molecular structures showed that the Ni(II) in both [NiL · HPyr] and [NiL · HIm] are in a distorted square planar environment and is coordinated to the dianionic NNS tridentate hydrazoneoxime ligand via deprotonated oximate nitrogen, hydrazone imine nitrogen, and thiolate sulphur. The fourth coordination sites are occupied, respectively, by the pyrazole and imidazole nitrogens. The oximate O1 of [NiL · HPyr] is involved in intramolecular hydrogen bond with the pyrazole NH proton as well as intermolecular hydrogen bond pyrazole C6H proton, forming a helical chain propagating along the b-axis. The structure is stabilized by a set of π?π and CH?π interactions. The molecular units in [NiL · HIm] are linked together by hydrogen bond formation between the oximate oxygen and imidazole NH proton, giving rise to an infinite zigzag chain extended along the a-axis. The chains are interconnected by π?π and CH?O interactions. In [Ni(HL)₂] · H₂O, the Ni(II) is in a distorted octahedral environment. The two mononegative hydrazoneoxime ligands are coordinated in the meridional configuration where the two thiol sulphur atoms and the two oxime nitrogen atoms are cis to each other, while the imine nitrogen atoms are trans. The oxime proton O2H is involved in a reciprocal bifurcated hydrogen bond formation with both N2 and S3 of the adjacent molecule giving rise to hydrogen bonded dimer. This dimeric structure is further stabilized by a pair of reciprocal CH?O interactions. A one dimensional chain of alternating dimeric unit and water molecule propagating along the c-axis is formed via hydrogen bond formation between the oxime O1 oxygen and the bridged water molecule proton.     

Intertwining Operators Associated to a Family of Differential-Reflection Operators

Mediterranean Journal of Mathematics - We introduce a family of differential-reflection operators $${\Lambda_{A, \varepsilon}}$$ acting on smooth functions defined on $${{\mathbb R}}$$ . Here, A is...     

Synthesis and antimicrobial evaluation of novel 1,3-thiazoles and unsymmetrical azines

Research on Chemical Intermediates - 1,3-Thiazol derivatives have been synthesized via reaction of 1-(1-(5,6-dimethoxy-2-oxobenzo[d]thiazol-3(2H)-yl)propan-2-ylidene)-4-substituted...