Electrochemical and spectral properties of the polymer form of Cu(II) complex with N,N′-bis(salicylidene)-1,3-propylenediamine

A conductive polymer based on the Cu(II) complex with N,N′-bis(salicylidene)-1,3-propylenediamine was obtained electrochemically. The optimal mode of the synthesis of the polymer under potentiostatic conditions was found. We determined the charge diffusion coefficient and activation barrier and elucidated the nature of the limiting step of the charge transfer in the polymer bulk in the electrolyte medium. The azomethine base, Cu(II) complex, and its polymer form in the oxidized and reduced states were characterized by X-ray photoelectron spectroscopy and electron absorption spectroscopy.     

Synthesis of tetrazolodiazepines by a five-centered four-component azide Ugi reaction. Scope and limitations

Tetrazolo[1,5-a][1,4]benzodiazepines were obtained by an efficient azide five-centered four-component Ugi reaction, which used ketones, sodium azide, ammonium chloride, and the corresponding isonitrile. Scope and limitations of this multi-component reaction were considered.     

Quantum Hamiltonians with Weak Random Abstract Perturbation. I. Initial Length Scale Estimate

We study random Hamiltonians on finite-size cubes and waveguide segments of increasing diameter. The number of random parameters determining the operator is proportional to the volume of the cube. In the asymptotic regime where the cube size, and consequently the number of parameters as well, tends to infinity, we derive deterministic and probabilistic variational bounds on the lowest eigenvalue, i.e., the spectral minimum, as well as exponential off-diagonal decay of the Green function at energies above, but close to the overall spectral bottom.     

The new frozen spin target at MAMI

The new frozen spin polarized target for experiments at the polarized beam of the real photon facility A2 of the MAMI accelerator is described. The A2-collaboration at the Mainz Microtron MAMI is measuring photon absorption cross section using circularly and linearly polarized photons up to the energy of 1.5 GeV. The photons are produced in the’ Bremsstrahlungs’ process. In the years 2005/2006 the Crystal Ball detector with its unique capability to cope with multi photon final states was set up in Mainz. Since 2010 the experimental apparatus has been completed by a polarized target. The horizontal dilution refrigerator of the Frozen-Spin Target has been constructed and is operated in close cooperation with the Joint Institute for Nuclear Research in Dubna, Russia. The system offers the opportunity to provide longitudinally and transversely polarized protons and deuteron. In this paper the operation experience of this new Frozen-Spin Target and first results from the runs in 2010 and 2011 are presented.     

Periodic dyadic wavelets and coding of fractal functions

Recently, using the Walsh-Dirichlet type kernels, the first author has defined periodic dyadic wavelets on the positive semiaxis which are similar to the Chui-Mhaskar trigonometric wavelets. In this paper we generalize this construction and give examples of applications of periodic dyadic wavelets for coding the Riemann, Weierstrass, Schwarz, van der Waerden, Hankel, and Takagi fractal functions.     

Ignition and combustion of isopropyl nitrate

The ignition delay times for mixtures of isopropyl nitrate (IPN) with air and argon are measured in a rapid-injection reactor at a pressure of 1 atm and in a shock tube at 2–3 atm. It is shown that the ignition delay time τ of mixtures in which heat is largely released due to oxidation by the oxygen contained in the IPN molecule is determined by the unimolecular decomposition of IPN over the entire temperature range covered (500–730 K). For mixtures in which heat is mainly produced by oxidation reactions involving air oxygen, the ignition delay time at high temperatures is controlled by secondary reactions of oxidation of the hydrocarbon moiety of the IPN molecule, leading to an increase in τ by more than an order of magnitude. Liquid IPN burns in a nitrogen atmosphere only at pressures above 40 atm, at a linear rate of ~4 mm/s. The measured flame temperatures are in close agreement with the respective values calculated using a thermodynamic code.     

Dynamics of Water Absorption by the Copolymer of Dimethyldiallylammonium Chloride and Acrylic Acid

Russian Journal of General Chemistry - The swelling of the cyclochain copolymer of N,N-dimethyl-N,N-diallylammonium chloride with acrylic acid in water was studied. For the first time, an increase...     

Synthetic Transformations of Higher Terpenoids. 41. Synthesis and Anti-Inflammatory Activity of 4-(Carboxyalkyl)-18-nor-isopimara-7,15-Dienes

Chemistry of Natural Compounds - Synthetic methods were developed for isopimaric acid derivatives, the terminal carboxylic acid of which was separated by two or three methylenes from the tricyclic...     

Crystallographic Analysis of the Structure of LaBiI<Subscript>6</Subscript>·13H<Subscript>2</Subscript>O and NdBiI<Subscript>6</Subscript>·13H<Subscript>2</Subscript>O. Sublattice of Iodine Atoms: A Common Skeleton of the Structures

The crystallographic analysis of the recently determined structures of LaBiI₆·13H₂O and NdBiI₆·13H₂O reveals that their common basis is a sublattice of iodine anions built of coherently assembled octahedral I₆ fragments. The relationship between the parameters of orthorhombic and monoclinic unit cells of these structures is shown and their symmetry features are discussed.