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1.
We predict ultraslow collapse of “tubular image states” (TIS) on material surfaces. TIS are bound Rydberg-like electronic states formed at large distances (∼30 nm) from the surfaces of suspended circularly-symmetric nanowires, such as metallic C nanotubes. The states are formed in potential wells, resulting from a combination of the TIS-electron attraction to image charges in the nanotube and its centrifugal repulsion, caused by spinning around the tube. We demonstrate that TIS can collapse on the tube surface by passing their angular momentum l to circularly polarized flexural phonons excited in the tube. Our analysis shows that for highly detached TIS with l ? 6 the relaxation lifetimes are of the order of 10 ns-1 μs, while for l < 6 these lifetimes are reduced by several orders of magnitude. 相似文献
2.
R. Hefelmann P. Mann A. Aignan F. Filsinger und H. Amsel 《Fresenius' Journal of Analytical Chemistry》1902,41(1):66-68
Ohne Zusammenfassung 相似文献
3.
Vijay Balasubramanian Donald Marolf Moshe Rozali 《General Relativity and Gravitation》2006,38(11):1529-1536
We argue that if black hole entropy arises from a finite number of underlying quantum states, then any particular such state
can be identified from infinity. The finite density of states implies a discrete energy spectrum, and, in general, such spectra
are non-degenerate except as determined by symmetries. Therefore, knowledge of the precise energy, and of other commuting
conserved charges, determines the quantum state. In a gravitating theory, all conserved charges including the energy are given
by boundary terms that can be measured at infinity. Thus, within any theory of quantum gravity, no information can be lost
in black holes with a finite number of states. However, identifying the state of a black hole from infinity requires measurements
with Planck scale precision. Hence observers with insufficient resolution will experience information loss.
First Award in the 2006 Essay Competition of the Gravity Research Foundation. 相似文献
4.
In this note we show that many classes of global optimization problems can be treated most satisfactorily by classical optimization theory and conventional algorithms. We focus on the class of problems involving the minimization of the product of several convex functions on a convex set which was studied recently by Kunoet al. [3]. It is shown that these problems are typical composite concave programming problems and thus can be handled elegantly by c-programming [4]–[8] and its techniques. 相似文献
5.
Intensity-dependent absorption of 25 ns excimer laser pulses in common UV-window materials was investigated. By employing a calorimetric technique which provides greatly enhanced sensitivity compared to transmissive measurements, two-photon absorption coefficients were determined at intensities of 2–80 MW/cm2 and found to be in good agreement with previous measurements at 10–100 GW/cm2. Also, color-center formation in fused silica was observed. It was possible to quantify transient and cumulative effects as a function of intensity. 相似文献
6.
Peroxyoxalate chemiluminescence may be used for sensitive postcolumn detection of phenothiazine analytes separated by high performance liquid chromatography with appropriate optimization of measurement conditions such as solvent, pH and oxalate ester. Detectability of fluorescent analytes by chemical excitation varies greatly, but analytes with low oxidation potentials are generally more readily detected at low levels, as demonstrated for phenothiazines, an important class of fluorescent drugs. Some improvement in detection limits is observed for fluphenazine when chemiluminescence detection is compared to conventional fluorescence detection. Because of the specificity of chemical excitation, fewer interferences from fluorescent impurities in a urine matrix are observed. 相似文献
7.
Stable Subnorms II 总被引:2,自引:0,他引:2
Moshe Goldberg Robert Guralnick W. A. J. Luxemburg 《Linear and Multilinear Algebra》2003,51(2):209-219
In this paper we continue our study of stability properties of subnorms on subsets of finite-dimensional, power-associative algebras over the real or the complex numbers. 相似文献
8.
9.
10.
Moshe Kress 《Annals of Operations Research》2006,148(1):5-23
Handling bioterror events that involve contagious agents is a major concern for authorities and a cause for debate among policymakers
about the best response policy. At the core of this debate stands the question which of the two post-event policies to adopt:
mass vaccination or trace (also called ring or targeted) vaccination. We present a new dynamic epidemic-intervention model that captures key features of the situation and generalizes
some previous assumptions regarding the probability distributions of inter-temporal parameters. It is shown that a mixture
of mass and trace vaccination policies—the prioritized vaccination policy—is more effective than either of the two aforementioned policies. 相似文献