Synthesis of Ni-based catalysts by hexamethylenetetramine-nitrates solution combustion method for co-production of hydrogen and nanofibrous carbon from methane

It was shown that hexamethylenetetramine (HMT)is a new effective fuel for single-step solutions combustion synthesis (SCS)of supported Ni catalysts for methane decomposition into hydrogen and nanofibrous carbon. Several generalized chemical equations reflecting different ideas about combustion of the HMT−Ni(NO 3 ) 2 −Cu(NO 3 ) 2 −Al(NO 3 ) 3 −H 2 O system have been derived. On the basis of those equations the adiabatic combustion temperature (T ad )and the amount of gaseous products (n g )have been calculated depending on the ignition temperature (T 1 ), water content (m), excess fuel coefficient (φ), and the composition of the obtained solid product. The calculations have shown that T ad , depending on m and φ, changes from hundreds to thousands of degrees Kelvin. Increase of Al 2 O 3 content in the catalyst up to 0.6 increases T ad by hundreds of degrees, and that increase of the Ni:NiO ratio up to 0.5 lowers T ad by tens of degrees. Three samples of the supported unreduced 0.97NiO/0.03Al 2 O 3 catalyst were successfully prepared with the help of the SCS method using HMT as the fuel at φ=0.7. Those samples, obtained at reaction mixture preliminary heating rates V = 1, 10, 15 K/min were characterised using XRD, TEM, and SEM, and further tested in a pure methane decomposition reaction (100 L CH4 /h/g cat , 823К, 1 bar). Nanoparticles of metal Ni were found in the SCS products, in contrast to cases when other types of fuel were used with

Velocity field distributions due to ideal line vortices

We evaluate numerically the velocity field distributions produced by a bounded, two-dimensional fluid model consisting of a collection of parallel ideal line vortices. We sample at many spatial points inside a rigid circular boundary. We focus on ``nearest neighbor'' contributions that result from vortices that fall (randomly) very close to the spatial points where the velocity is being sampled. We confirm that these events lead to a non-Gaussian high-velocity ``tail'' on an otherwise Gaussian distribution function for the Eulerian velocity field. We also investigate the behavior of distributions that do not have equilibrium mean-field probability distributions that are uniform inside the circle, but instead correspond to both higher and lower mean-field energies than those associated with the uniform vorticity distribution. We find substantial differences between these and the uniform case.Comment: 21 pages, 9 figures. To be published in Physical Review E (http://pre.aps.org/) in May 200

Application of an Oil-Displacing Composition for Increasing Flow Rate of Low Producing High-Viscosity Oil Wells of the Usinskoye Oil Field

The results of a pilot application of a chemical composition for enhanced oil recovery developed at the IPC SB RAS are presented. The EOR-composition was tested in 2014 at the Permian-Carboniferous heavy oil deposit at the Usinskoye oil field. It is very effective for an increase in oil production rate and decrease in water cuttings of well production. In terms of the additionally produced oil, the resulting effect is up to 800 tons per well and its duration is up to 6 months. The application of technologies of low-productivity-well stimulation using the oil-displacing IKhNPRO system with controlled viscosity and alkalinity is thought to be promising. This composition is proposed for the ‘cold’ stimulation of high-viscosity oil production as an alternative to thermal methods

MASTER: The Mobile Astronomical System of Telescope-Robots

We present the first russian robot-telescope designed to make prompt observations of gamma-ray bursts (http://observ.pereplet.ru). The telescopes are near Moscow. The system of telescopes with prompt pointing rates connects to the internet. The main parameters are the following: Richter-Slefogt system telescope (355 mm, f/d=2.4); Richter-Slefogt system telescope (200mm, f/d=2.4); Flugge system telescope (280mm, f/d=2.5); TV-camera with 20x40 degree objective; Two CCD cameras (Pictor 416); One CCD Apogee Camera AP16E. The type of mount is German with 8 grad/sec slew rate. MASTER images stars down to 19 magnitude in a 1 min exposure covering 6 square degrees.Comment: 3 pages, 2 figure

Prompt, early, and afterglow optical observations of five gamma-ray bursts (GRBs 100901A, 100902A, 100905A, 100906A, and 101020A)

We present results of the prompt, early, and afterglow optical observations of five gamma-ray bursts, GRBs 100901A, 100902A, 100905A, 100906A, and 101020A, made with the Mobile Astronomical System of TElescope-Robots in Russia (MASTER-II net), the 1.5-m telescope of Sierra-Nevada Observatory, and the 2.56-m Nordic Optical Telescope. For two sources, GRB 100901A and GRB 100906A, we detected optical counterparts and obtained light curves starting before cessation of gamma-ray emission, at 113 s and 48 s after the trigger, respectively. Observations of GRB 100906A were conducted with two polarizing filters. Observations of the other three bursts gave the upper limits on the optical flux; their properties are briefly discussed. More detailed analysis of GRB 100901A and GRB 100906A supplemented by Swift data provides the following results and indicates different origins of the prompt optical radiation in the two bursts. The light curves patterns and spectral distributions suggest a common production site of the prompt optical and high-energy emission in GRB 100901A. Results of spectral fits for GRB 100901A in the range from the optical to X-rays favor power-law energy distributions with similar values of the optical extinction in the host galaxy. GRB 100906A produced a smoothly peaking optical light curve suggesting that the prompt optical radiation in this GRB originated in a front shock. This is supported by a spectral analysis. We have found that the Amati and Ghirlanda relations are satisfied for GRB 100906A. An upper limit on the value of the optical extinction on the host of GRB 100906A is obtained.Comment: 18 pages, 14 figures, 14 tables, 5 machine readable tables; accepted for publication in MNRA