Ternary semigroups

A ternary semigroup is a nonempty set together with a ternary multiplication which is associative. Analogous to the theory of semigroups, a regularity condition on a ternary semigroup is introduced and the properties of regular ternary semigroups are studied. Associated with a ternary semigroup, a semigroup called the semigroup cover is constructed and its properties are investigated.     

Validated HPLC-Fl Method for the Analysis of S-Adenosylmethionine and S-Adenosylhomocysteine Biomarkers in Human Blood

The natural methyl donor group, S-adenosylmethionine and its product, S-adenosylhomocysteine play an important role in many biochemical reactions involving transmethylation reactions. These compounds can be used as biomarkers in incipient diagnosis of various pathological disorders therefore the validation of a suitable method to routinely analysis of these compounds is very important. In this paper, a high performance liquid chromatrography method for S-adenosylmethionine and S-adenosylhomocysteine measurement as fluorescent 1,N ⁶-ethanoderivatives from biological samples was validated in terms of selectivity, linearity range of the response (R?>?0.9993), detection limit (9?×?10^?9 and 4.4?×?10^?9 molL^?1), the limit of quantitation (9.7?×?10^?9 and 5.7?×?10^?9?mol?L^?1), precision, trueness and robustness. The method for quantification simultaneous of these compounds is rapid, sensitive and precise and appropriate for clinical analysis.     

Many-body interactions in semiconductors probed by optical two-dimensional fourier transform spectroscopy

We study many-body interactions between excitons in semiconductors by applying the powerful technique of optical two-dimensional Fourier transform spectroscopy. A two-dimensional spectrum correlates the phase (frequency) evolution of the nonlinear polarization field during the initial evolution and the final detection period. A single two-dimensional spectrum can identify couplings between resonances, separate quantum mechanical pathways, and distinguish among microscopic many-body interactions.     

Characterization of ion transport property in hot-press cast solid polymer electrolyte (SPE) films: [PEO: Zn(CF3SO3)2]

Characterization of ion transport property in dry solid polymer electrolyte (SPE) films: [PEO: Zn(CF₃SO₃)₂] in different salt wt% ratio has been reported. SPE films have been prepared by a hot-press casting procedure. Salt concentration dependent conductivity study at room temperature identified SPE film: [90PEO: 10 Zn(CF₃SO₃)₂] as optimum conducting composition (OCC) with σ _rt ~ 1.09 × 10⁻⁶ S/cm which is approximately three orders of magnitude higher than that of pure PEO host (σ _rt ~ 3.20 × 10⁻⁹ S/cm). The reason attributed for σ _rt enhancement has been the increase in degree of amorphous phase in polymeric host after salt complexation. This has been confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and polarized optical microscopy (POM) analysis. To evaluate the usefulness of SPE OCC film in all-solid-state-battery applications, ion transport property has been characterized in terms of basic ionic parameters viz. ionic conductivity (σ) and total ionic (t _ion)/cation (t ₊) transport numbers. Mechanism of ion transport has been explained by temperature dependent conductivity measurements and the activation energy (E _a) has been computed by least square linear fitting of “log σ − 1/T” Arrhenius plot.

     

Study of some properties of poly(N-vinyl imidazole) partially quaternized with n-butyl bromide aqueous solutions

This paper presents a study of the properties of aqueous solutions of poly(N-vinyl imidazole) quaternized with n-butyl bromide (PVIQ3). The influence of the temperature and polymer concentration on refractive index, electrical conductivity and surface tension was studied. The critical micelar concentration of PVIQ3 in aqueous solution was determined and correlated with the polymer solubility in water.All the PVIQ3 aqueous solutions properties were compared with those of poly(N-vinyl imidazole) (PNVI) and the influence of the quaternization process on the polymer properties was evidenced.     

Multi-component, 1,3-dipolar cycloaddition reactions for the chemo-, regio- and stereoselective synthesis of novel hybrid spiroheterocycles in ionic liquid

A library of novel 1-methyl-4-arylpyrrolo-(spiro[2.2′]indan-1′,3′-dione)-spiro[3.3″]-1″-methyl/benzyl-5″-(arylmethylidene)piperidin-4″-ones and 1-methyl-4-arylpyrrolo-(spiro[2.11′]-11H-indeno[1,2-b]quinoxaline)-spiro[3.3″]-1″-methyl/benzyl-5″-(arylmethylidene)piperidin-4″-ones have been synthesized via 1,3-dipolar azomethine ylide cycloaddition in the ionic liquid, 1-butyl-3-methylimidazolium bromide ([BMIm]Br), in excellent yields.     

Hydrogen diffusivity,kinetics of H2O/H2 charge transfer and corrosion properties of LaNi5-powder,composite electrodes in 6 M KOH solution

Meticulous analysis of galvanostatic charge/discharge dependencies of the LaNi₅-based, powder composite electrode, in terms of determination of characteristic kinetic parameters of hydrogen storage electrode materials working in concentrated alkaline solution has been carried out. A special attention has been paid to the precise determination of charge and discharge times. The cathodic curves reveal their stepwise nature which allows to receive information of hydride material corrosion phenomena and determine the real time of atomic hydrogen absorption. The graphical way of determining of reduction times, based on differential cathodic curves is proposed. The knowledge of hydrogen absorption and desorption times allows to determine hydrogen diffusivity within the tested material with acceptable accuracy. The effect of external pressure (0.5–4 bar) on hydrogen absorption ability of LaNi₅-based material is also discussed. The exchange current density of H₂O/H₂ system distinctly increases with external pressure, at the same time, kind of gas atmosphere (Ar or H₂) scarcely affects the exchange current on the LaNi₅ electrode. The hydrogen capacity increases when the charge/discharge rate decreases. The reduction times of oxide phases formed during electrode discharge can be a measure of material corrosion rate. It is shown that the rate of LaNi₅ corrosion process strongly increases with the electrode cycling.     

α-(3,7-Dioxa-r-1-azabicyclo[3.3.0]oct-c-5-ylmethoxy)-diazines. Part 2: Functionalisation via directed ortho-metallation and cross-coupling reactions

The functionalisation of the title compounds via regioselective Directed ortho-Metallation (DoM) and cross-coupling reactions is studied. The compatibility of the 3,7-DiOxa-r-1-AzaBicyclo[3.3.0]Oct-c-5-ylmethoxy system (DOABO-CH₂O) to typical reaction conditions is established. Its role as Directed ortho-Metallation Group (DoMG) is examined, including competition with classical DoMGs, chlorine and methoxy. The chelating ability of some functionalised terms such as DOABO-CH₂O substituting chiral diarylmethanols and polyaza analogues of 2,6-terpyridine is discussed as intramolecular steric relationships determining configuration and aptitude to bind selectively transition metals, respectively.