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581.
582.
H. J. Sue E. I. Garcia-Meitin B. L. Burton C. C. Garrison 《Journal of Polymer Science.Polymer Physics》1991,29(13):1623-1631
A novel technique which utilizes a two-stage staining approach, (i.e., styrene absorption followed by osmium tetraoxide staining) is introduced for staining saturated polyacrylate rubbers. This novel staining approach, which stains and hardens polyacrylate rubber, is found to be useful for room temperature microtomy of polyacrylate rubber-modified polymers. Therefore, both the morphology and the crack tip toughening mechanisms of polyacrylate rubber-modified systems can be studied. Details concerning staining time, staining media, and use of solvents are discussed. 相似文献
583.
T. A. Burton 《Annali di Matematica Pura ed Applicata》1994,167(1):341-350
This research was carried out under a grant form C.N.R. (Italy) while the author was visiting the University of Firenze in the fall of 1992. That support and the gracious hospitality of that university are gratefully acknowledged. 相似文献
584.
585.
A dependent percolation model is a random coloring of the two-lattice. It is assumed that there are a finite number of colors and that the coloring is translation invariant. Each color defines a random subset of the lattice. Connected components of this subset are called clusters. This paper gives a classification of the infinite behavior of these clusters. In particular, it is shown that the lattice is divided into disjoint infinite strips, lying adjacently. Each strip is either composed of an infinite cluster together with isolated finite clusters or else is entirely composed of finite clusters. Examples of the various types of behavior are constructed. 相似文献
586.
We show that if σ is the Bernoulli shift on sequences of {?1, 1} with equiprobable product measure andT is a suitable mixing entropy zero trnsformation then the skew product defined byS(x,y)=(σx,T x0 y) is Bernoulli. 相似文献
587.
C. Oppenheimer P. Bani J.A. Calkins M.R. Burton G.M. Sawyer 《Applied physics. B, Lasers and optics》2006,85(2-3):453-460
We report here the results of a field campaign in which a portable Fourier transform infrared (FTIR) spectrometer was used to measure gas emissions from Yasur volcano, Vanuatu, in January 2005. By collecting FTIR spectra at a high rate (about 1 Hz), we were able to observe a marked difference in the proportions of SO2 and HCl in emissions released during Strombolian eruptions (SO2/HCl molar ratio up to ∼30 or more) compared with the intervening passive emissions discharged from the magmatic vent (SO2/HCl ∼2). This contrast can be explained by sourcing gas at different depths with respect to levels at which SO2 and HCl exsolve from the melt: deeper volatile exsolution supplies relatively SO2-rich gas responsible for the ephemeral explosions at the top of the conduit; while degassing of shallow magma, depleted in sulfur but rich in chlorine, contributes to the passive emission. PACS 07.57.Ty; 91.40.Vg; 91.40.Yt; 91.40.Zz 相似文献
588.
Peter G. Burton 《Chemical physics letters》1982,87(1):101-104
Accurate ab initio Cl calculations of interaction energies for He-He are shown to continue to be invaluable for the interpretation and assessment of experimental data for this system in both the low-and high-energy, part of the repulsive wall. 相似文献
589.
590.
Witherspoon F.D. Burton R.L. Goldstein S.A. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1989,17(3):353-359
A series of railgun experiments has been performed using Lexan insulators in both round and square bores, and with closed-breech and open-breech/injected configurations. Measured armature lengths have been roughly constant at 5-10 cm in a 1-cm bore for all Lexan insulator shots, indicating that the ablated Lexan is not swept up. Projectiles have been observed to reach peak velocity of 5.65 km/s with clean armature structures: i.e. no separated secondary arc or restrike. However, in most cases a secondary arc does occur with Lexan and limits the achievable velocity. Occasionally, stationary secondary arcs have also been observed for a particularly leaky gun assembly. The effect of insulator ablation on performance is discussed, indicating that Lexan may be useful at up to 8-10 km/s for well-sealed railguns 相似文献