The structure and properties of polyethylene films obtained during orientational crystallization

Highly oriented films possessing increased tensile strengths (based on initial cross section) and elastic moduli are produced directly in the extrusion process. The dependence of the structure and properties of these films on hardening temperature is studied. Assumptions are made concerning the formation and crystallization mechanisms of films produced with higher molecular orientation.     

Spectral investigation of a mixed isonitrile-carbonyl extracomplex of meso-tetraphenylporphyrinatoiron(II) at low temperatures

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 3, pp. 421–426, September, 1990.     

Dependence of X-ray diffraction patterns on the parameters of primary incident beam

X-ray diffraction patterns obtained from a plane-parallel crystalline plate with a spherical cavity and from a wedge-shaped crystal have been investigated depending on the collimation of the primary incident beam. It is shown that in the case of ribbon-like incident beam the sectional topograms, obtained from the wedge-shaped crystal, have the form of V-shaped or straight fringes depending on the orientation of reflecting planes relative to the surface of the X-ray ribbon-like beam. In the case of a wide parallel beam or an asymmetrically reflected wide monochromatic beam the parallel fringes are obtained from the wedge-shaped crystals, and the circular fringes are obtained from the plane-parallel crystalline plates with a spherical cavity. For the primary ribbon-like beam the V-shaped patterns acquire the form of circular fringes as a result of scanning the crystal with a spherical cavity and the X-ray film.     

Surface Structure Modification and Deuterium Retention in Tungsten under Pulsed Plasma Loads

Modification of the surface layer and deuterium accumulation in tungsten targets under plasma irradiation in a quasi-stationary plasma accelerator with an intrinsic magnetic field QSPA-T, which reproduces the conditions (plasma thermal load of 0.2-5 MJ/m2, pulse duration of 0.1-1.2 ms) typical of ELM events in ITER, are studied. Using a scanning electron microscope, structure modifications at the surface and in the bulk after deuterium plasma irradiation are analyzed. The observed changes in the near-surface layer are compared with the calculated data on the change in the internal structure of tungsten under intense thermal action obtained as a result of the numerical solution of the heat conduction problem. The total deuterium retention in the samples was measured using thermal desorption spectroscopy, and it was in the range of (3-4) × 1016 particles/cm2 for the samples melted during plasma exposure. These numbers exceed by an order of magnitude the values obtained for samples without traces of melting.     

Features of the reaction of 4-bromobut-2-enylphosphonium salts with monosubstituted hydrazines

(4-Bromobut-2-en-1-yl)triphenylphosphonium bromide reacted with phenylhydrazine at 2°C in the presence of sodium carbonate to form triphenyl[4-(2-phenylhydrazinylidene)but-2-en-1-yl]phosphonium bromide in 62% yield. The obtained N-phenylhydrazine derivatives cyclized into the corresponding pyrazoline derivatives of phosphonium salts. Unlike phenylhydrazine, ethylhydrazine reacted with (4-bromobut-2-ene-1-yl)triphenylphosphonium bromide under the same conditions to afford triphenyl[(1-ethyl-4,5-dihydro-1Hpyrazol-3-yl)methyl]- and -[(1-ethyl-1H-pyrazol-3-yl)methyl]phosphonium bromides in yields of 60 and 40%.     

Electron and hole states in a narrow-band semiconductor InSb film in the presence of uniform electrostatic field

The states of charge carriers in a narrow-gap semiconductor InSb film, placed in a uniform electrostatic field, are considered theoretically. We consider the case when the heavy holes are described by the standard dispersion, and Kane’s dispersion law takes place for electrons and for light holes within the framework of two-band mirror model. For a certain range of values of the external field, explicit expressions for the energy spectrum and the envelope wave functions of charge carriers are obtained. Corresponding numerical estimations of allowed range of the external field are derived, for which the proposed approach allows exact analytical solutions.     

Synthesis and Biological Activity of Arylcyclopentane-1-carboxylic Acids Aminoesters

Russian Journal of General Chemistry - 1-Arylcyclopentane-1-carboxylic acids were synthesized by alkaline hydrolysis of the corresponding nitriles. Reactions of the acid chlorides with...     

Noise in p+nn+ structures based on semiconductor compensated by doubly charged acceptors

The results are presented of a theoretical calculation of the spectra of generation-recombination and diffusion noise in p⁺nn⁺ structures whose base region is compensated by an impurity that creates doubly charged deep acceptor centers. The results of experimental studies of noise processes in such structures are provided. The theoretical results are compared with the experimental data.     

Design,antihuman immunodeficiency activity and molecular docking studies of synthesized 2-aryl and 2-pyrimidinyl pyrrolidines

Molecular Diversity - A series of thirty-one new compounds were synthesized and evaluated for their anti-HIV-1 and cytotoxicity activity. Of these, twelve were found to be inhibitors of HIV...