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831.
A. G. Kudashov L. G. Bulusheva A. V. Okotrub O. G. Abrosimov Yu. V. Shubin L. I. Yudanova N. F. Yudanov 《Inorganic Materials》2007,43(9):945-950
Nitrogen-containing carbon nanotubes have been prepared via acetonitrile (CH3CN) pyrolysis at 850°C catalyzed by nanoparticles produced by the thermal decomposition of zinc and nickel bimaleates and their solid solutions. The synthesized samples have been characterized by transmission electron microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. The results demonstrate that increasing the zinc content of catalyst nanoparticles reduces the yield of carbon nanotubes and increases the nitrogen content of the material. The high synthesis temperature gives rise to zinc vaporization, which influences the growth process, increasing the nanotube diameter, reducing the wall thickness, and lowering the structural perfection of the graphite layers. 相似文献
832.
Bench-scale reactor experiments were performed to study the dissolution of a binary naphthalene-in-nonane mixture nonaqueous phase liquid (NAPL) pool over a wide range of average pore water velocities, vx (≈0.1–60 m/day). Experimental NAPL pool dissolution flux values were determined using a steady-state mass balance approach. The experimental flux data were compared to model predictions made assuming either local equilibrium or mass-transfer limited conditions. The local equilibrium model could describe the trends in the average effluent concentration and dissolution flux with 0.110?m/day. Data determined to be under mass-transfer limited conditions were fit to the nonequilibrium model to estimate values for an overall mass-transfer coefficient. The calculated overall mass-transfer coefficients had an average value of 0.407 m/day and showed no correlation with vx, probably due to mass-transfer resistance becoming dominated by the diffusional resistance in the NAPL. These results suggest that the nonequilibrium approach is better suited for describing high velocity (vx>10?m/day) dissolution of multicomponent NAPL pools, and that flushing of groundwater at very high velocities may not be an effective approach for enhancing NAPL-pool dissolution flux. 相似文献
833.
N. S. Pronkin R. B. Sharafutdinov O. M. Kovalevich A. A. Smetnik A. G. Levin S. A. Kabakchi O. L. Masanov 《Atomic Energy》2003,94(6):398-404
This paper is devoted to the development of a method for hazard classification of holding ponds at the Industrial Association Mayak, the Siberian Intergrated Chemical Plant, and the Integrated Iron-Mining and Mining-Chemical Plant. The method is based on a combined approach employing the qualitative characteristics and quantitative parameters of the ponds. The classification of holding ponds is intended to be used for developing the requirements for the composition and content of the documentation presented by enterprises for licensing the operation and decommissioning of holding ponds. 相似文献
834.
Hierarchically ordered structures facilitate the incorporation of diverse functions simultaneously. The present report introduces a simple and novel strategy for producing hierarchically ordered polymeric films. Hierarchical ordering of aqueous droplets on a polymer solution is realized by the imposition of physical confinement via various shaped gratings. After drying of the solution, well‐ordered hierarchical structures were fabricated in the remaining polymer film. The size of the grating structure and the lattice size of spontaneous hexagonally packed aqueous pores comprise two different length scales, thereby offering multiscale ordering. Interfacial wetting of the polymer solution to the grating surface was crucial in terms of obtaining a highly ordered structure that can be tuned by dissolving a small amount of surfactant in the polymer solution. The present novel approach provides a new opportunity for lithography‐free fabrication of complex hierarchical structures. 相似文献
835.
In this work, we co‐formulated an oil‐borne copper naphthenate/permethrin wood preservative system with synthetic polymer‐based fire‐retardant additives prior to the impregnation of Pinus radiata sapwood. We evaluated what effect, if any, the preservative had upon the fire performance properties of the fire retardants and whether the fire retardants impacted on the fungicidal and termiticidal efficacy of the preservative. The fire retardants included halogenated and phosphorus‐based systems. A mass loss calorimeter, in conjunction with a thermopile, was used to measure the time to ignition and the peak heat release rate (PHRR) from which the fire performance index (FPI) was determined. The preservative properties were evaluated using termite and soil‐block decay bioassays. In summary, we found that the rate of fire growth was reduced when the fire retardants were used in combination with the wood preservative. We also found that the PHRR was a better determinant of fire performance than the FPI. The performance of the wood preservative was enhanced against fungal decay and termite attack when used in combination with the fire retardants. The fire retardants also demonstrated some wood preservative properties of their own. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
836.
837.
Calculation and experimental methods showed that the use of lithium metaphosphate for making up batches of Li2O-Li2SO4-P2O5 multilithium glass systems reduces the founding temperature-time parameters while simultaneously increasing the homogeneity of the melts. 相似文献
838.
839.
840.
M. S. Avilov A. V. Akimov A. V. Antoshin P. A. Bak Yu. M. Boimel'shtein D. Yu. Bolkhovityanov R. Kh. Galimov R. G. Gromov K. V. Gubin S. M. Gurov E. A. Gusev N. S. Dikanskii I. V. Kazarezov S. N. Klyushchev V. I. Kokoulin E. S. Konstantinov A. A. Korepanov N. Kh. Kot R. M. Lapik N. N. Lebedev A. I. Lobas P. V. Logachev P. V. Martyshkin L. A. Mironenko V. M. Pavlov I. L. Pivovarov O. V. Pirogov V. V. Podlevskikh S. L. Samoilov Yu. I. Semenov B. A. Skarbo A. A. Starostenko O. Yu. Tokarev A. R. Frolov V. D. Khambikov A. S. Tsyganov A. G. Chupyra S. V. Shiyankov 《Atomic Energy》2003,94(1):50-55
The VÉPP-5 injection complex under construction at the Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences is a powerful source of intense electron and positron bunches at 510 MeV, which covers all needs of the electron–positron colliding beam setups currently operating and under construction at the Institute of Nuclear Physics. The complex includes a 285 MeV linear electron accelerator, a 510 MeV linear positron accelerator, and an accumulator–cooler with beam injection and ejection channels. Intense work on the design, assembly, and tuning of the linear electron accelerator has been conducted in the last 2 yr. As a result, by August 2002 the linear electron accelerator was put into operation with all standard subsystems. By this time, the isochronous achromatic turning of the electron beam, a system for converting electrons into positrons, and the first accelerating structure of the linear positron accelerator were assembled and put into operation. All this made it possible to accelerate the positron beam up to 75 MeV. Preliminary results of tests of the linear accelerators are presented. 相似文献