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961.
A methodology remediating zones of local radioactive contamination is presented. It is based on a classification of the zones
taking account of the contribution of external and internal irradiation to the total dose load to the public. The criteria
for identifying such loads and the steps required for their remediation are identified. A radiation-ecological validation
of the decrease in the external irradiation dose to the public in zones of local radioactive contamination is given.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 2, pp. 125–134, February, 2006. 相似文献
962.
Modeling of photonic crystal structures is an ongoing challenge. This letter is devoted to the theoretical modeling of photonic crystal resonant cavities, composed of elliptically shaped dielectric pillars. Through this rigorous study, we can examine the impact of the elliptical-shape deformations to important quantities related to the photonic crystal cavity performance, such as the quality factor and the resonance frequency. 相似文献
963.
O. N. Klimova 《Journal of Computer and Systems Sciences International》2007,46(6):903-907
The problem of the choice of optimal chemical composition of shipbuilding steel in the presence of several optimal criteria is considered. The solution of the problem is based on particular results of the theory of relative importance of criteria and uses particular numerical information on relative importance of criteria. 相似文献
964.
In-Situ and Real-Time Investigation of Columnar-to-Equiaxed Transition in Metallic Alloy 总被引:1,自引:0,他引:1
H. Nguyen-Thi G. Reinhart N. Mangelinck-Noël H. Jung B. Billia T. Schenk J. Gastaldi J. Härtwig J. Baruchel 《Metallurgical and Materials Transactions A》2007,38(7):1458-1464
In this article, we present a review of observations during Al-3.5 wt pct Ni alloy solidi.cation experiments performed at
the European Synchrotron Radiation Facility (ESRF) in Grenoble. These experiments provide direct access to dynamical phenomena
during columnar growth (initial transient and breakdown of a planar solid-liquid interface), and for the first time to the
transition from columnar-to-equiaxed microstructure (nucleation ahead of a columnar front and blocking of a columnar front
by an equiaxed microstructure) and fully equiaxed growth (propagation of an effective front). Based on these experimental
observations, critical parameters such as columnar growth velocity variation during the transition or equiaxed-grain diameter
are measured and discussed.
This article is based on a presentation made in the symposium entitled “Solidi.cation Modeling and Microstructure Formation:
In Honor of Prof. John Hunt,” which occurred March 13–15, 2006, during the TMS Spring Meeting in San Antonio, Texas, under
the auspices of the TMS Materials Processing and Manufacturing Division, Solidification Committee. 相似文献
965.
K.F. Chan C.K. Wan K.N. Yu 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,262(1):128-134
In the present work, we have studied the feasibility of a method based on polyallyldiglycol-carbonate (PADC) films to investigate the effects of alpha particles on HeLa cervix cancer cells. Thin PADC films with thickness of about 20 μm were prepared from commercially available CR-39 films by chemical etching to fabricate custom-made petri dishes for cell culture, which could accurately record alpha particle hit positions. A special method involving “base tracks” for aligning the images of cell nuclei and alpha particle hits has been proposed, so that alpha particle transversals of cell nuclei can be visually counted. Radiobiological experiments were carried out to induce DNA damages, with the TdT-mediated dUTP Nick-End Labeling (TUNEL) fluorescence method employed to detect DNA strand breaks. The staining results were investigated by flow cytometer. The preliminary results showed that more strand breaks occurred in cells hit by alpha particles with lower energies. Moreover, large TUNEL positive signals were obtained even with small percentages of cells irradiated and TUNEL signals were also obtained from non-targeted cells. These provided evidence for the bystander effect. 相似文献
966.
967.
Consideration was given to the characteristic polynomials with special affine uncertainty. For this family, the stability domain in the parameter space was shown to be a union of polyhedra. For continuous-time and discrete-time systems, a simple method was proposed to single out the stability domain and determine the stability radius for different norms of uncertainty. Efficiency of this method was corroborated by examples. 相似文献
968.
Remote sensing of species mixtures in conifer plantations using LiDAR height and intensity data 总被引:2,自引:0,他引:2
Daniel N.M. Donoghue Peter J. Watt Nicholas J. Cox Jimmy Wilson 《Remote sensing of environment》2007,110(4):509-522
In even-aged, single species conifer plantations LiDAR height data can be modelled to provide accurate estimates of tree height and volume. However, it is apparent that growth models developed for single species stands are not directly transferable to a more general situation of mixed species plantations. This paper evaluates the ability of small footprint, dual-return, pulsed airborne LiDAR data to estimate the proportion of the productive species when mixed with a nurse crop in closed canopy plantations. A study area located in Galloway Forest District in Scotland is used as an example of Lodgepole pine and Sitka spruce mixed plantation; this area contains good examples of a wide range of pure and mixed species plantation types. Three species groups are studied: areas of pure Sitka spruce, areas of pure Lodgepole pine and areas where the two species have been planted together. Two approaches are assessed for detection of plantation mixtures: the first uses LiDAR intensity data to separate spruce and pine species and the second uses LiDAR-derived canopy density measures, coefficient of variation, skewness, percent of ground returns (which provides a measure of canopy openness) and the mean canopy height, which enables areas with height variations to be identified. From analysis of LiDAR data extracted from 54 study plots using logistic regression, the coefficient of variation and LiDAR intensity data provide the most useful predictors of the proportion of spruce in a pine/spruce mixture with coefficients of determination (R2) of 0.914 and 0.930 respectively. The method could be developed as a mapping tool, which in combination with existing inventory data should help to improve timber volume forecasting for mixed species even-aged plantations. 相似文献
969.
V. M. Krutskikh M. V. Ivanov A. B. Drovosekov E. N. Lubnin B. F. Lyakhov Yu. M. Polukarov 《Protection of Metals》2007,43(6):560-566
The structures, chemical states of elements, and catalytic activities of Ni-Mo-B alloys with different molybdenum contents,
which were obtained by catalytic electroless reduction of metal ions, were studied. The rates of the partial reactions (heterogeneous
hydrolysis of dimethylamine borane, reduction of nickel ions, and evolution of molecular hydrogen) were found to make a bell-shaped
curve when plotted versus the concentration of molybdate ions in solution.
Original Russian Text ? V.M. Krutskikh, M.V. Ivanov, A.B. Drovosekov, E.N. Lubnin, B.F. Lyakhov, Yu.M. Polukarov, 2007, published
in Zashchita Metallov, 2007, Vol. 43, No. 6, pp. 619–625. 相似文献
970.
L. G. Korshunov Yu. N. Goikhenberg N. K. Chernenko 《Metal Science and Heat Treatment》2007,49(5-6):217-226
The effect of nitrogen, silicon, and aging modes on the structure, resistance to abrasive and adhesive wear, friction factor,
and mechanical properties of nitrogen-bearing (0.27–0.83% N) chromium-manganese austenitic steels is studied. It is shown
that it is possible to ensure a favorable combination of mechanical and tribological properties in such steels by choosing
the appropriate chemical composition and aging mode.
__________
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 5, pp. 9–18, May, 2007. 相似文献