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91.
The goal of this research is to prepare a series of alloys having sharp, reproducible magnetic transitions for calibrating temperature in thermogravimetry from the magnetic transition temperature of pure cobalt (1121°C) to below room temperature.Alloys in the Ni-Co and Ni-Cu systems were prepared by the thermal decomposition of coprecipitated oxalates in argon. The alloys were subsequently annealed under 5% hydrogen.Magnetic transition temperatures were measured using simultaneous thermomagnetometry/differential thermal analysis. Transition temperatures were corrected using well known meltingpoint standards. Magnetic transition temperatures along with precision are reported as a function of composition. 相似文献
92.
W. H. P. Pernice F. P. Payne D. F. G. Gallagher 《Optical and Quantum Electronics》2006,38(9-11):843-856
In this paper, we present a formulation of the finite-difference time-domain method for the simulation of metallic structures. The frequency dependent dielectric function of metals is approximated by a combined Drude–Lorentzian multi-pole expansion and fitting errors of only a few percent are obtained. An auxiliary differential equation technique is used to extend the standard FDTD algorithm with the dispersive material equations. The algorithm is validated by calculating reflection and transmission coefficients for thin metal layers, elliptical nano-particles and by simulating a surface plasmon resonance device. Excellent agreement between the FDTD simulations and exact theoretical results are obtained. 相似文献
93.
Jones R.R. Zhu Y. Eichmann U. Gallagher T.F. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1988,16(5):534-540
The multiphoton double ionization of Ba from ~280 to 700 nm was investigated using laser pulses 5 ns long of peak intensity ~1010 W/cm2. The spectrum consists of a number of strong resonances, which can be assigned to Ba+ transitions. Most of the assignments have been verified by pump-probe techniques. Thus, the Ba++ observed is due to sequential ionization. The multiphoton ionization probability is highest for λ~500 nm, which matches a series of strong Ba and Ba+ transitions leading to double ionization 相似文献
94.
95.
96.
Purine photoproducts 总被引:2,自引:0,他引:2
Abstract— DNA purine modifications by ultraviolet irradiation have not been as extensively studied as those of pyrimidines. However, a number of such reactions have been identified. These include photochemical addition of amino acids, photoalkylation by alcohols, amines and other compounds, photochemical activation of procarcinogens to mutagenic electrophiles, and formation of covalent linkages between DNA purines and adjacent bases. The recent characterization of two adenine-adenine di-adducts and the finding of endonucleases from two sources that incise ultraviolet-irradiated DNA at purine photoproducts indicate the possible biological importance of these moieties. 相似文献
97.
98.
Mimi Y. Keating Andrew R. McGhie Patrick K. Gallagher Roger L. Blaine Tammy Chalmers et al. 《Journal of Thermal Analysis and Calorimetry》1991,37(3):689-689
Events
Announcement 相似文献99.
100.
R. J. Gallagher 《Journal of Optimization Theory and Applications》1995,84(3):665-674
In 1953 Arrow, Barankin, and Blackwell proved that, ifR
n
is equipped with its natural ordering and ifF is a closed convex subset ofR
n
, then the set of points inF that can be supported by strictly positive linear functionals is dense in the set of all efficient (maximal) points ofF. Many generalizations of this density result to infinite-dimensional settings have been given. In this note, we consider the particular setting where the setF is contained in the topological dualY
* of a partially ordered, nonreflexive normed spaceY, and the support functionals are restricted to be either nonnegative or strictly positive elements in the canonical embedding ofY inY
*. Three alternative density results are obtained, two of which generalize a space-specific result due to Majumdar for the dual system (Y,Y
*)=(L
1,L
).This research was supported in part by funds provided by the Provident Chair of Excellence in Applied Mathematics at the University of Tennessee, Chattanooga, Tennessee. 相似文献