ARIMA,cointegration, Kalman-filter, α -stable distributions

A group of scientists, from Ukraine, the United Kingdom and Switzerland met at the 3rd International Congress on Industrial and Applied Mathematics (ICIAM95) Hamburg. They decided to pool their applied research efforts and experiences in the domain of mathematics, statistics and economics and to collaborate in empirical research on the subject of the transitional economies of Ukraine and Eastern Europe after 1989. The activity started in autumn 1995 within the framework of a project titled Analysis of Economic and Environmental Time Series (AEETS).At theMinisymposium Cointegrating, Kalman Filtering of Economic Time Series, α-stable Distributions, of the ICIAM07 in Zurich, the AEETS group has presented a sample of recently treated questions. In this abstract two of these subjects are summarised. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Novel regular polyimide‐graft‐(polymethacrylic acid) brushes: Synthesis and possible applications as nanocontainers of cyanoporphyrazine agents for photodynamic therapy

An approach to the synthesis of new regular graft‐copolymers polyimide (PI)‐graft‐polymethacrylic acid is elaborated, including (1) synthesis of multicenter PI macroinitiators, (2) controlled ATRP of tert‐butylmethacrylate on the prepared macroinitiators, and (3) protonolysis of tert‐butyl ester groups of side chains of the resulting PI‐graft‐poly(tert‐butylmethacrylate). Experimental conditions for attaining complete conversions of the first and the third stages of the process are determined by means of ¹H NMR and FTIR‐spectroscopy. Polymer products of the first and the second stages of the process, as well as poly(tert‐butylmethacrylate) side chains cleaved from the PI‐graft‐poly(tert‐butylmethacrylate) copolymers by complete decomposition of the PI backbone under alkaline hydrolysis conditions, are characterized by GPC. The kinetics of poly(tert‐butylmethacrylate) chain growth on a PI macroinitiator under ATRP conditions are studied. The results obtained provide evidence for the controlled character of the ATRP process and the regular structure of the synthesized graft‐copolymers. It is shown that PI‐g‐PMAA PI brushes are significantly more efficient intracellular delivery agents for the potential photosensitizer [tetra(4‐fluorophenyl)tetracyanoporhyrazine free base] than are the commonly used PEG‐micelles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4267–4281     

Radical anions of flavonoids

Several representatives of natural flavonoids and their synthetic nitro‐derivatives have been investigated by polarography and electron paramagnetic resonance (EPR) spectroscopy under electrochemical reduction in acetonitrile, dimethylformamide (DMF), dimethylsulfoxide (DMSO) or 1,2‐dimethoxyethane. All the compounds studied are reduced in the first stage by one‐electron transfer, apart from flavanone, which accepts two electrons simultaneously. However, the primary radical anions were detected by EPR spectroscopy only for 4′‐nitroflavone. It was shown that radical anions of other flavonoids quickly dimerized. The analysis of the temperature dependence of the hyperfine interaction constants and broadening of lines in EPR spectra of 4′‐nitroflavone radical anions has shown that the distribution of spin density is due to both the change of polarity of the medium and rotation of the nitrophenyl moiety. The assignment of hyperfine structure constants for the 4′‐nitroflavone radical anion was confirmed by density functional theory (DFT) calculations. Copyright © 2011 John Wiley & Sons, Ltd.     

Stabilized Silver Nanoparticles and Nanoclusters Ag<Subscript>n</Subscript> in Humic-Based Bioactive Nanocomposites

Silver-containing nanocomposites synthesized from the compounds of a humic series have been studied using modern physical–chemical methods (EPR, TEM, IR and XRD, etc.). It is shown that the humic substances with different functional groups and isolated from different sources have also different ability of stabilizing the silver nanoparticles. Long-term stable nanoparticles and silver clusters have been found. A multiplet, observed in the EPR spectra of silver-containing nanocomposites, which are obtained from humic substances isolated from therapeutic muds and shales, is assigned to the formed Ag_n nanoclusters. Formation of the silver molecular clusters depends on the kind of humic substances and depth of their decomposition.     

The reaction of 4-(1,3,2-benzodioxaphosphol-2-yloxy)-3-tert-butylpent-4-en-2-one with hexafluoroacetone

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Numerical predictions of oblique detonation stability boundaries

Oblique detonation stability was studied by numerically integrating the two-dimensional, one-step reactive Euler equations in a generalized, curvilinear coordinate system. The integration was accomplished using the Roe scheme combined with fractional stepping; nonlinear flux limiting was used to prevent unphysical solution oscillations near discontinuities. The method was verified on one- and two-dimensional flows with exact solutions, and its ability to correctly predict one-dimensional detonation stability boundaries was demonstrated. The behavior of straight oblique detonations attached to curved walls was then considered. Using the exact, steady oblique detonation solution as an initial condition, the numerical simulation predicted both steady and unsteady oblique detonation solutions when a detonation parameter known as the normal overdrive, , was varied. For a standard test case with a specific heat ratio of , a dimensionless activation energy of , and dimensionless heat release of , an oblique detonation with a constant dimensionless component of velocity tangent to the lead shock, , underwent transition to unstable behavior at . This is slightly higher than the threshold of predicted by one-dimensional theory; thus, the two-dimensionality renders the flow slightly more susceptible to instability. Received 4 August 1996 / Accepted 5 March 1996     

Synthesis of Thin-Film Acidic Ti(IV) and Zr(IV) Phosphates Deposited on Surface of Fiber and Investigation their Properties

Abstract

Cellulosic fibres present great interest as matrix for non-organic synthesis with the use of ion-molecular layering method [I]. This method consists in realization of the successive reactions with the surface functional groups. Synthesized materials can he of scientific and technical interest.