A simple and convenient synthesis of [1,2,4]triazolo/benzimidazolo ‎quinazolinone and [1,2,4]triazolo[1,5-<Emphasis Type="Italic">a</Emphasis>]pyrimidine derivatives catalyzed by ‎DABCO-based ionic liquids

DABCO-based ionic liquids were utilized for the preparation of [1,2,4]triazolo/benzimidazolo quinazolinone and [1,2,4]triazolo[1,5-a]pyrimidine derivatives in the adequate procedures. These methods involve three-component reaction between aldehydes, β-diketones and 3-amino-1,2,4-triazole or 2-aminobenzimidazole in the presence of 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium chloride ([DABCO](SO₃H)₂(Cl)₂) and 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium dihydrogen sulfate ([DABCO](SO₃H)₂(HSO₄)₂) as reusable and economical catalysts at 100 °C. These methods also show eco-friendly characters by elimination of solvent. Any by-product was not prepared through this method, and products were separated by a simple workup procedure. The other noticeable benefits of these procedures are excellent yields, short reaction times, mild reaction conditions and use of available and inexpensive materials.     

Study of the eigenwaves of a coplanar transmission line using the method of partial operator inversion

We propose a partial inversion procedure for the Cauchy singular integral and the integral with a logarithmic singularity determined on a finite set of bounded intervals. On the basis of this procedure, we constructed an electrodynamic model of a shielded coplanar transmission line (CTL). The results of calculation of the spectral characteristics and eigenwave field distributions of this structure are presented and the data on convergence of the approximate solution are given. Volga State Academy of Telecommunications and Information Sciences, Samara, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 43, No. 6, pp. 552–561, June, 2000.     

Spectra of some block operator matrices and application to transport operators

In this paper a new concept for a 3×3 block operator matrix is studied on a Banach space. It is shown that, under certain conditions, it defines a closable operator and its essential spectra are determined. Application to transport operators in L₁-space is given.     

Essential Spectra of a 3 × 3 Operator Matrix and an Application to Three-Group Transport Equations

In this paper we study spectral properties of a 3 × 3 block operator matrix with unbounded entries and with domain consisting of vectors which satisfy certain relations between their components. It is shown that, under certain conditions, this block operator matrix defines a closed operator, and the essential spectra of this operator are determined. These results are applied to a three-group transport equation.     

Perturbation of unbounded linear operators by $$\gamma $$-relative boundedness

Diagana (Handbook on operator theory. Springer, Basel, pp 875–880, 2015) studied some sufficient conditions such that if S,  T and K are three unbounded linear operators with S being a closed operator, then their algebraic sum \(S+T+K\) is also a closed operator. The main focus of this paper is to extend these results to the closable operator by adding a new concept of the gap and the \(\gamma \)-relative boundedness inspired by the work of Jeribi et al. (Linear Multilinear Algebra 64:1654–1668, 2015). After that, we apply the obtained results to study the specific properties of some block operator matrices.     

String field theory: From high energy to cosmology

We review recent achievements and open questions in string field theory. We comment on the history of the construction of the covariant gauge-invariant string field formulation and briefly consider possible applications of string field theory in D-brane physics and cosmology.     

Holographic relation between p-adic effective action and string field theory

We consider two holographically related theories. As the first (d + 1)-dimensional theory, we consider a model in which the (d + 1)-dimensional space is the direct product of ? ^d and the half-axis ?₊ and in which the kinetic operator has a nonlocal term induced by the nonlocal kinetic operator of the p-adic effective action. It turns out that the kinetic operator in the second, holographically related, d-dimensional theory is the kinetic operator of the string field theory effective action.     

On a characterization of the essential spectra of the sum and the product of two operators

In this paper, we consider the sum and the product of two operators acting on a Banach space and we present some new and quite general conditions to investigate their Wolf, Schechter and Browder essential spectra.     

Mesoporous cadmium sulfide nanoparticles derived from a new cadmium anthranilato complex: Characterization and induction of morphological abnormalities in pathogenic fungi

A cadmium complex of the general formula Cd(C₁₃H₉O₂NCl)₂(H₂O)₂ {C₁₃H₉O₂NCl = 2-(4-chlorophenylamino)benzoate} was synthesized and characterized regarding its CHN data, solution molar conductivity and spectroscopic (UV–Vis. and IR) properties. Cadmium sulfide nanoparticles (CdS NPs) were grown form the microcrystalline complex and thiourea via a hydrothermal route. The as-prepared NPs were assigned based on X-ray powder diffraction (PXRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and Brunauer – Emmett – Teller (BET) surface area measurements. The CdS absorption and emission spectra were also recorded that revealed an energy gap of 2.47 eV and large Stokes shift of 130 nm. For the as-prepared NPs, the measurements have also indicated a mesoporous structure and an average particle size of 20–28 nm associated with an average pore diameter of 11.21 nm. The as-synthesized CdS NPs acted as antifungal controlling agent against human and plant pathogenic fungi of serious environmental and health concerns. The NPs at concentration of 200 ppm inhibited several fungi with inhibition efficiency of 100% against Aspergillus ustus Au-28. The nanoparticles induced morphological abnormalities in fungal mycelia, conidia and vesicle. Additionally, they inhibited the conidia septum formation, accelerated the chlamydospores generation and enlarged the yeast cells.