Transition of graphite into diamond in a solid phase under the atmospheric pressure

Transition of small-size graphite particles into diamond has been experimentally detected under atmospheric pressure. The transformation in a solid phase occurs when graphite heated up to 2500 K is rapidly cooled. Electron and X-ray diffraction methods were applied to investigate the solid-phase transition products. The transition of graphite into diamond may be explained whether by the setting up of high pressures or by retention in quenching the structures that are characteristic for elevated temperatures.     

Reduction of Np(VI) with Hexamethylenetetraacetic Acid in HClO4 Solution

Radiochemistry - Spectroscopic method was used to examine the stoichiometry of the reaction of No(VI) with hexamethylenediaminetetraacetic acid (HMDTA, H4hmdta) in a 0.05 M HClO4 solution. At an...     

Extraction of U(VI), Th(IV), Pu(IV), and Am(III) from nitric acid solutions with polyfunctional organophosphorus acids

Extraction of microamounts of U(VI), Th(IV), Pu(IV), and Am(III) nitrates from aqueous HNO₃ solutions with solutions of (diphenylphosphinylmethyl)phenylphosphinic, (di-p-tolylphosphinylmethyl)phenylphosphinic, and (dioctylphosphinylmethyl)phosphinic acids and of butyl hydrogen (diphenylphosphinylmethyl)phosphonate in organic diluents was studied. The metal: extractant stoichiometric ratio in the extractable complexes was determined, and the diluent effect on the extraction efficiency was examined. The possibility of using a macroporous polymeric sorbent impregnated with (dioctylphosphinylmethyl)phenylphosphinic acid for concentrating metal ions from HNO₃ solutions was demonstrated.     

Disproportionation of nonoxygenated U(V) bound in the complex with heteropoly anions P<Subscript>2</Subscript>W<Subscript>17</Subscript>O<Stack><Subscript>61</Subscript><Superscript>10−</Superscript></Stack>

The effect of experimental conditions on U^VL₂ (1–2 mM) disproportionation was studied spectrophotometrically through the U^IVL₂ accumulation (L = P₂W₁₇O ₆₁ ^10? ). In 1 M NaNO₃ solution containing 0.01 M HAc and 0.01 M NaAc, the rate of U^VL₂ disappearance is described by the equation V = k ₁[U^VL₂]. The k ₁ value is almost constant with pH decreasing from 4.5 to 1.7, but increases with increasing acetate concentration; the presence of 1 mM U^IVL₂, U(VI), or L does not affect k ₁. In the solutions of 0.1–1.0 M HClO₄ (ionic strength 1), the reaction rate is described by the equation V = 2k ₂[H⁺]^2.5[U^VL₂]². Probable disproportionation mechanism is discussed. The first stage is substitution of L by water molecules in the U^IVL₂ complex and appearance of the reactive U(V) complex with mixed coordination sphere.     

Preparation of Macrocrystalline Tungsten-Based Alloys by Electron-Beam Floating Zone Melting

Inorganic Materials - Macrocrystalline tungsten alloys containing 1, 3, and 5 at % alloying additives (Re, Mo, Ta, Cr, Fe, and V) have been prepared by electron-beam floating zone melting. The...     

Method for estimating lineature by scanned samples of documents

The paper considers an algorithm for estimating lineature of scanned digital images based on the calculation of series lengths and local directional fields. The results of an experiment are given and the efficiency of the algorithm is investigated. Vitalii Anatol’evich Mitekin. Born in 1983. Graduated from Samara State Aerospace University (SSAU) in 2006. At present, he is a post-graduate student in the Department of Geoinformatics at SSAU. His scientific interests include image processing, stenography, and cryptography. He is the author of three publications, including three articles. Viktor Andreevich Fedoseev. Born in 1986. Defended a degree thesis at the Samara State Aerospace University in 2007. Continues teaching at the SSAU at present, and also works as a technician at the Institute of Image Processing Systems at the Russian Academy of Sciences. His scientific interests include computer graphics, image processing, stenography, and cryptography. He is the author of 11 publications, including six articles.     

Estimating Synergetic Openness of Industrial Enterprise Management Systems

The problem of comprehensive assessment of available enterprise management systems from implementation and application viewpoint is discussed. The degree of information system’s synergetic openness, which described system’s ability to respond to external users’ requests by means of built-in self-organization mechanisms and tools, is offered as an integrated quality index. This complex index depends of partial factors, describing system’s adaptability and integrability. With the help of comprehensive assessment the available ERP systems are compared, and the need in taking into account industrial user’s specific features during system selection is demonstrated.     

A dual-wave atmosphere transparency radiometer of the millimeter wave range

The MIAP-2 radiometric complex intended for measuring the atmospheric absorption in the millimeter wavelength range (2 and 3 mm) is described. The complex is based on two solid-state modulation radiometers with wave ranges of 84–99 GHz and 132–148 GHz, which are equipped with horn-lens antennas. The device determines an optical depth in the millimeter wave range using the atmospheric-dip method and the absolute signal calibration method in the fully automated mode under the remote control via the Internet. A set of observations was performed in the stationary mode and in mountain expedition conditions. The reliability of the device was evaluated from 2-year operation results.