Structure of Substituted 5-Chloromethyloxazolidines

By means of ¹H NMR spectroscopy isomerism was demonstrated in N-alkyl substituted 5-chloromethyl-1,3-oxazolidines due to relative cis-trans orientation of substituents in 2 and 5 positions of the ring. The preferred configuration in 2,3-diaryl-5-chloromethyl-1,3-oxazolidines, cis-(2R,5R), was proved by quantum-chemical calculations.     

Synthesis and antibacterial activity of fluoroquinolones with sterically hindered phenolic moieties

Russian Chemical Bulletin - Fluoroquinolone antibiotics (norfloxacin, ciprofloxacin, and moxifloxacin) modified at the piperazine ring by sterically hindered phenolic moieties were synthesized and...     

An evaluation of interface capturing methods in a VOF based model for multiphase flow of a non-Newtonian ceramic in tape casting

The aim of the present study is to evaluate the different interface capturing methods as well as to find the best approach for flow modeling of the ceramic slurry in the tape casting process. The conventional volume of fluid (VOF) method with three different interpolation methods for interface capturing, i.e. the Geometric Reconstruction Scheme (GRS), High Resolution Interface Capturing (HRIC) and Compressive Interface Capturing Scheme for Arbitrary Meshes (CICSAM), are investigated for the advection of the VOF, both for Newtonian and non-Newtonian cases. The main purpose is to find the best method for the free surface capturing during the flow of a ceramic slurry described by a constitutive power law equation in the tape casting process. First the developed model is tested against well-documented and relevant solutions from literature involving free surface tracking and subsequently it is used to investigate the flow of a La_0.85Sr_0.15MnO₃ (LSM) ceramic slurry modeled with the Ostwald de Waele power law. Results of the modeling are compared with corresponding experimental data and good agreement is found.     

Sorption Catalytic Determination of Copper(II) and L-α-alanine on Mg-, Al-Layered Double Hydroxides

Mg-, Al and Mg-, Cu-, Al-layered double hydroxides well-known synthetic hydrotalcite-like sorbents, were used for the first time as carriers for indicators in the sorption catalytic determination of copper(II) and L-α-alanine. Mg-, Al and Mg-, Cu-, Al-layered double hydroxides were synthesized by coprecipitation and characterized using infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The adsorption of 0.50?mg?L^?1 copper(II) solution by Mg-, Al-layered double hydroxides followed a pseudo-second-order model with an equilibrium sorption capacity of 24.2?×?10^?3?mg?g^?1 (3.8?×?10^?4?mmol g^?1) and a reaction rate constant of 4.2?g mg^?1?min^?1. Mg-, Al-layered double hydroxide tablets were prepared and used for sorption concentration and subsequent sensitive and selective sorption catalytic determination of 5.5?×?10^?3 to 1.0?mg?L^?1 copper(II) at the sorbent phase. The method was used for the analysis of natural water. A method was developed for the determination of α-alanine in Mg-, Cu-, Al-layered double hydroxide tablets with a limit of detection of 4.0?×?10^?3 mol?L^?1. In addition, thin layers of Mg-, Cu-, Al-layered double hydroxide were used to separate α-alanine and determine α-amino acids by thin-layer chromatography.     

Ethylene dinitrodiamine in the addition reaction to α, Β-unsaturated ketones

Summary The addition of ethylene dinitrodiamine to , -unsaturated ketones was investigated and it was established that the former is readily added to unsaturated ketones with formation of new N-nitroketones.     

Order-optimal methods for the approximation of a piecewise-continuous solution to a certain inverse problem

The authors propose an order-optimal method for the approximation of a piecewise-continuous solution to a certain inverse problem and obtain exact by order bounds for the error of this approximation in the uniform metrics on segments of continuity of the exact solution to the problem.     

Error estimation for an approximate solution of an inverse problem in thermal diagnostics

In thermal diagnostics of rocket engines [1], account should be taken of the physical properties of composite materials in use. This allows inverse boundary value problems to be solved for parabolic equations with discontinuity coefficients. High requirements that are imposed on the accuracy of approximate solutions of the given class of problems make it possible to obtain error estimations for the methods employed.