Electronic structure and UV–Vis spectra simulation of square planar Bis(1-(4-methylphenylazo)-2-naphtol)-Transition metal complexes [M(L)2]x (M = Ni,Pd, Pt,Cu, Ag,and x = − 1, 0, + 1): DFT and TD-DFT study

Structural Chemistry - DFT/B3LYP calculations with full geometry optimizations have been carried out on 1-phenylazo-2-naphthol and their metal complexes of formula M(MePhNap)2 (M?=?Ni,...     

Non-abelian isometries and dimensional reduction

Dimensional reduction is carried out for space-times, with or without torsion, which possess non-abelian isometries. The spectra and the equations of motion of the dimensionally reduced theory are obtained directly from the higher dimensional theory. The spectra of the reduced theories are naturally given in terms of scalar fields and antisymmetric tensor field strengths. A method of studying the dependence on the extra dimensions is suggested.     

Cost,Revenue and Profit Efficiency Models in Generalized Fuzzy Data Envelopment Analysis

One of the most important information given by data envelopment analysis models is the cost, revenue and profit efficiency of decision making units (DMUs). Cost efficiency is defined as the ratio of minimum costs to current costs, while revenue efficiency is defined as the ratio of maximum revenue to current revenue of the DMU. This paper presents a framework where data envelopment analysis (DEA) is used to measure cost, revenue and profit efficiency with fuzzy data. In such cases, the classical models cannot be used, because input and output data appear in the form of ranges. When the data are fuzzy, the cost, revenue and profit efficiency measures calculated from the data should be uncertain as well. Fuzzy DEA models emerge as another class of DEA models to account for imprecise inputs and outputs for DMUs. Although several approaches for solving fuzzy DEA models have been developed, numerous deficiencies including the $\alpha$-cut approaches and types of fuzzy numbers must still be improved. This scheme embraces evaluation method based on vector for proposed fuzzy model. This paper proposes generalized cost, revenue and profit efficiency models in fuzzy data envelopment analysis. The practical application of these models is illustrated by a numerical example.     

Phytochemical Profile,Antioxidant Capacity, α-Amylase and α-Glucosidase Inhibitory Potential of Wild Moroccan Inula viscosa (L.) Aiton Leaves

Medicinal plants offer imperative sources of innovative chemical substances with important potential therapeutic effects. Among them, the members of the genus Inula have been widely used in traditional medicine for the treatment of several diseases. The present study investigated the antioxidant (DPPH, ABTS and FRAP assays) and the in vitro anti-hyperglycemic potential of aerial parts of Inula viscosa (L.) Aiton (I. viscosa) extracts through the inhibition of digestive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. The polyphenolic profile of the Inula viscosa (L.) Aiton EtOAc extract was also investigated using HPLC-DAD/ESI-MS analysis, whereas the volatile composition was elucidated by GC-MS. The chemical analysis resulted in the detection of twenty-one polyphenolic compounds, whereas the volatile profile highlighted the occurrence of forty-eight different compounds. Inula viscosa (L.) Aiton presented values as high as 87.2 ± 0.50 mg GAE/g and 78.6 ± 0.55mg CE/g, for gallic acid and catechin, respectively. The EtOAc extract exhibited the higher antioxidant activity compared to methanol and chloroform extracts in different tests with (IC₅₀ = 0.6 ± 0.03 µg/mL; IC₅₀ = 8.6 ± 0.08 µg/mL; 634.8 mg ± 1.45 AAE/g extract) in DPPH, ABTS and FRAP tests. Moreover, Inula viscosa (L.) Aiton leaves did show an important inhibitory effect against α-amylase and α-glucosidase. On the basis of the results achieved, such a species represents a promising traditional medicine, thanks to its remarkable content of functional bioactive compounds, thus opening new prospects for research and innovative phytopharmaceuticals developments.     

Enhancement of catalytic activity in the synthesis of 2-amino-4H-chromene derivatives using both copper- and cobalt-incorporated magnetic ferrite nanoparticles

Research on Chemical Intermediates - Cu0.5Co0.5Fe2O4 magnetic nanoparticles were prepared, characterized and employed as bench-top, highly active and magnetically separable nanocatalysts for the...     

Study of the ionic conductivity of some fluorides of monovalent and tetravalent elements

Recently some interest has attached to ionic conductivity in the fluorides of metals with large cation radius because of the high fluorine mobility in these materials.A.c. conductivity measurements using the complex impedance method were carried out on sintered samples and showed that some binary fluorides of monovalent elements (M^I = K, Rb, Tl) and tetravalent elements (M^IV = Zr,Hf, Th, U) exhibit an appreciable ionic conductivity at moderate temperature : σ at 200°C (Ω^?1 cm^?1) Tl₃ZrF₇ 3.5 × 10^?3 Tl₂ZrF₆ 1.1 × 10^?2 Tl ZrF₅ 5 × 10^?4A single crystal study of Tl₃ZrF₇ shows that this compound crystallizes in the cubic system with space group Fm3m and cell parameter a = 9.34 Å. Therefore its crystal structure may be related to that of (NH₄)₃ZrF₇ [1 to 3] which is characterized by the presence of (ZrF₇)^3? ions with a pentagonal bipyramid as probable configuration. There are two crystallographically independent fluorine ions in position (96 j) of the space group Fm3m with a percentage of occupancy of 20.8 and 8.3 respectively. Thus Tl₃ZrF₇ is an example of fluoride where a three dimensional ionic conductivity occurs due to an incomplete occupation of a special symmetry position and where temperature increase might create rotation of (ZrF₇)^3? polyhedra giving rise to an important anionic disorder.In order to determine the origin of the ionic conductivity in TlZrF₅ we have undertaken the determination of the crystal structure of this fluoride from X-ray intensity measurements made with the aid of an automatic four circle diffractometer.TlZrF₅ cristallizes in the monoclinic system with unit-cell dimensions a = 8.112(1)Å, b = 7.927(3)Å, c = 7.929(1)Å, β = 123.99(1)° and space group P2 /c (No 14), Z = 4.In this structure, the Zr⁴⁺ ion is surrounded by eight F^? ions, the coordination polyhedron being a bicapped trigonal prism. This crystal structure consists of sheets (ZrF₅)^? that may be described as edge-shared and corner-shared bicapped trigonal prisms (ZrF₈). The sheets run parallel to the yOz plane and are bonded together by the Tl⁺ ions which are surrounded by twelve F^?ions. This arrangement produces relatively open tunnels in the b direction delimited by the cations. Of the five independent fluorine atoms, two of them, namely F(1) and F(4) are different from the other from the point of view of bonding and are located in these tunnels. Thus they are probably primarily responsible for the high conductivity of this material [4].With regard to Tl₂ZrF₆, it is the best as far as ionic conductivity is concerned. However its crystal structure is still unknown and its determination is actually under investigation in our laboratory.All this materials are good electronic insulators and their transport properties due to the high fluorine ion mobilities allow us to think that some of them hold considerable promise for use as solid electrolytes.     

A Primal-dual Interior-point Algorithm for Symmetric Cone Convex Quadratic Programming Based on the Commutative Class Directions

Acta Mathematicae Applicatae Sinica, English Series - In this paper, we present a neighborhood following primal-dual interior-point algorithm for solving symmetric cone convex quadratic programming...     

Nitric oxide delivery by core/shell superparamagnetic nanoparticle vehicles with enhanced biocompatibility

We report the synthesis of Fe(3)O(4)/silica core/shell nanoparticles and their functionalization with S-nitrosothiols. These nanoparticles are of immense interest because of their nitric oxide (NO) release capabilities in human alveolar epithelial cells. Moreover, they act as large storage reservoirs of NO that can be targeted magnetically to the specific site with a sustainable release of NO for up to 50 h. Such nanoparticles provide an enhancement of the biocompatibility with released NO while allowing intracellular accumulation ascribed to their small size.     

Non-linear analysis of structures using two-point method

Non-linear algebraic equations must be solved by an iterative method, the non-linear equations being linearized by evaluating the non-linear terms with the known solution from the preceding iteration. The Newton-Raphson method, which is based on the Taylor series expansion and uses the tangent stiffness matrix, has been extensively used to solve non-linear problems. In this paper, a new Newton-Raphson algorithm is developed for analyses involving non-linear behavior. Our method, here named as a two-point method, is constructed as a predictor-corrector one, most frequently taking Newton's method in the first iteration. It should be noted that our concern in this research ignores the problem of passing limit points. The presented method incorporates the known information at each stage of the loading process to determine the subsequent unknown variables. Compared with the classic Newton-Raphson algorithm, it offers a strategy that can be deployed to reduce both the number of the iterations and the computing time involved in non-linear analysis of structures.