Scaled constraint qualifications for generalized equation constrained problems and application to nonsmooth mathematical programs with equilibrium constraints

Positivity - In this paper, the notion of graphical derivatives is applied to define a new class of several well-known constraint qualifications for a nonconvex multifunction M at a point of its...     

Preparation and characterization of a novel water soluble amino chitosan (amino-CS) derivative for facilitated transport of CO<Subscript>2</Subscript>

With the goal of obtaining a water soluble polymeric carrier for preparation of fixed facilitated transport membranes, a water soluble amino containing chitosan derivative was prepared through Michael-addition reaction between chitosan and ethyl acrylate followed by amidation of the ester groups with an appropriate diamine. This derivative was characterized using ¹H-NMR spectroscopy. Then, facilitated transport membranes were prepared by casting a thin layer of chitosan derivative/poly(vinyl alcohol) blend on a porous polysolfune support; and the effect of fixed carrier’s content, feed temperature and feed pressure on the CO₂ permeance, and CO₂/CH₄ selectivity of produced membranes were studied. A facilitated transport mechanism for CO₂ through this membrane was concluded.     

CuI-catalyzed thioarylation of active methylene compounds with in situ generated benzenethiols: Preparation of α-thioaryl-β-dicarbonyls and 4-thioaryl-5-pyrazolones

In this paper, a one-step copper-catalyzed procedure for oxidative coupling of active methylene compounds including cyclic β-diketones, cyclic β-ketoesters and 5-pyrazolone with benzenethiols is described. Benzenethiols are in situ generated in the reaction mixture from aryl halides and thiourea as sulfur transfer reagent. α-Thioaryl compounds are obtained in excellent yields and in short reaction time via the process which is free from the foul smell of thiols.     

Processing and Properties of Nanofibrous Bacterial Cellulose-Containing Polymer Composites: A Review of Recent Advances for Biomedical Applications

Abstract

Bacterial cellulose (BC) is an extracellular natural polymer produced by many microorganisms and its properties could be tailored via specific fabrication methods and culture conditions. There is a growing interest in BC derived materials due to the main features of BC such as porous fibrous structure, high crystallinity, impressive physico-mechanical properties, and high water content. However, pristine BC lacks some features, limiting its practical use in varied applications. Thus, fabrication of BC composites has been attempted to overcome these constraints. This review article overviews most recent advance in the development of BC composites and their potential in biomedicine including wound dressing, tissue engineering scaffolds, and drug delivery. Special emphasis is placed on the fabrication and applications of BC-containing nanofibrous composites for biomedical usage. It summarizes electrospinning of BC-based nanofibers and their surface modification with an outline on challenges and future perspective.     

High performance liquid chromatographic determination of sodium benzoate, methylparaben and propylparaben as preservative components in nystatin suspensions

A simple and sensitive method was developed for the analysis of preservatives sodium benzoate, methylparaben and propylparaben in nystatin suspensions by reversed-phase high performance liquid chromatography (HPLC), equipped with a C18 column and PDA detector. The mobile phase was a mixture of acetonitrile and acetate buffer of pH 4.4 (35:65 v/v). Under the optimized experimental conditions, separation of the preservatives was achieved in less than 20 min. The limits of quantifications (LOQs) and the linear dynamic ranges (LDRs) of sodium benzoate, methylparaben and propylparaben were 0.3 and 50–1000 μg Ml^?1, 0.5 and 50–600 μg ml^?1 and 0.3 and 50–900 μg ml^?1, respectively; the respective precisions (%RSD) at 500 μg ml^?1 level were 0.72%, 0.73% and 0.51% (n = 6). The average recoveries of sodium benzoate, methylparaben and propylparaben for spiked nystatin samples were obtained as 98%, 97% and 98%, respectively.     

Computational study on the mechanism and thermodynamic of atmospheric oxidation of HCN with ozone

Oxidation of hydrogen cyanide with ozone on the singlet potential energy surface is carried out using the MP2 and CCSD(T)//MP2 theoretical approaches in connection with the 6-311++G(d,p) basis set. In this reaction, energy barrier of transition states are low, so the reaction of HCN with ozone can occur easily at atmospheric condition. With variety of pre-reactive complex, five types of products are obtained at the MP2 method which four types of them have enough thermodynamic stability at the standard condition. CO₂ + HNO are final adducts in a process that is computed to be exothermic by ?132.605 kcal/mol in standard enthalpy and spontaneous by ?144.166 kcal/mol in Gibbs free energy of reaction. In kinetic viewpoint, the production of OCN + HO₂ adducts path with one low level transition state is the most favored path.     

Extremal principle based on the linear subdifferential

An extremal principle in the vein of Mordukhovich is proved based on the linear generalized gradient.     

Nonsmooth Calculus of Semismooth Functions and Maps

In this paper, we pursue two goals. First, we find exact relationships between the three concepts of semismooth sets, functions, and maps. Then, we consider the nonsmooth calculus of these notions. Particularly, we prove that the Mordukhovich and linear subdifferentials (coderivatives) are equal for the semismooth functions (maps). Several examples are presented to illustrate the results of the paper.     

Calmness of Set-Valued Mappings Between Asplund Spaces and Application to Equilibrium Problems

The paper deals with the calmness of two classes of nonconvex set-valued mappings in Asplund spaces and its application to equilibrium problems. Its main part is devoted to establish new sufficient conditions for calmness, which are derived in terms of coderivatives and w* boundaries of normal cones to constraint sets. In order to achieve this goal, a new concept so-called “sequential normal smoothness” for the sets in Asplund spaces is introduced and compared with two well-known notions of convexity and semismoothness. Finally, the results are applied to prove necessary optimality conditions for nonparametric equilibrium problems under new weak constraint qualifications.