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181.
The geometry arising from Michelson & Strominger's study of =4B supersymmetric quantum mechanics with superconformal D(2, 1; )-symmetry is a hyperKähler manifold with torsion (HKT) together with a special homothety. It is shown that different parameters are related via changes in potentials for the HKT target spaces. For 0, –1, we describe how each such HKT manifold M
4m
is derived from a space N
4m–4
which is quaternionic Kähler with torsion and carries an Abelian instanton. 相似文献
182.
Eguchi K Enomoto S Furuno K Ikeda H Ikeda K Inoue K Ishihara K Iwamoto T Kawashima T Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Ogawa H Owada K Piquemal F Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Takayama T Tamae K Watanabe H Busenitz J Djurcic Z McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Goldman J Heeger KM Lesko KT Luk KB Murayama H Nygren DR Okada CE Poon AW Steiner HM Winslow LA Horton-Smith GA 《Physical review letters》2004,92(7):071301
Data corresponding to a KamLAND detector exposure of 0.28 kton yr has been used to search for nu;(e)'s in the energy range 8.3相似文献
183.
Mode-coupling theory (MCT) predicts the arrest of colloids in terms of their volume fraction, and the range and depth of the interparticle attraction. We discuss how the effective values of these parameters evolve under cluster aggregation. We argue that weak gelation in colloids can be idealized as a two-stage ergodicity breaking: first at short scales (approximated by the bare MCT) and then at larger scales (governed by MCT applied to clusters). The competition between the arrest and phase separation is considered in relation to recent experiments. We predict a long-lived "semiergodic" phase of mobile clusters, showing logarithmic relaxation close to the gel line. 相似文献
184.
185.
186.
We study a class of weighted shifts W
α defined by a recursively generated sequence α ≡ α0, … , α
m−2, (α
m−1, α
m
, α
m+1)∧ and characterize the difference between quadratic hyponormality and positive quadratic hyponormality. We show that a shift
in this class is positively quadratically hyponormal if and only if it is quadratically hyponormal and satisfies a finite
number of conditions. Using this characterization, we give a new proof of [12, Theorem 4.6], that is, for m = 2, W
α is quadratically hyponormal if and only if it is positively quadratically hyponormal. Also, we give some new conditions for
quadratic hyponormality of recursively generated weighted shift W
α (m ≥ 2). Finally, we give an example to show that for m ≥ 3, a quadratically hyponormal recursively generated weighted shift W
α need not be positively quadratically hyponormal. 相似文献
187.
We report a Fano resonance-based electrically reconfigurable add-drop filter using a microring resonator-coupled Mach-Zehnder interferometer (MZI) on a silicon substrate. Our experiments reveal a pair of complementary Fano resonance line shapes that can be electrically tuned and output coupled from the MZI output ports. A near symmetrical resonance peak can be flipped to a near symmetrical resonance dip by applying a forward-bias voltage of less than 1V across a laterally integrated p-i-n diode in the MZI non-resonator-coupled arm. Our scattering-matrix-based modeling shows good agreement with the experiments and indicates ways to enhance the resonance routing functionality. Our work demonstrates the feasibility of an integrated reconfigurable add-drop filter with actively interchangeable throughput and drop ports. 相似文献
188.
Emulsification of partially miscible liquids using colloidal particles: nonspherical and extended domain structures 总被引:1,自引:0,他引:1
Clegg PS Herzig EM Schofield AB Egelhaaf SU Horozov TS Binks BP Cates ME Poon WC 《Langmuir : the ACS journal of surfaces and colloids》2007,23(11):5984-5994
We present microscopy studies of particle-stabilized emulsions with unconventional morphologies. The emulsions comprise pairs of partially miscible fluids and are stabilized by colloids. Alcohol-oil mixtures are employed; silica colloids are chemically modified so that they have partial wettability. We create our morphologies by two distinct routes: starting with a conventional colloid-stabilized emulsion or starting in the single-fluid phase with the colloids dispersed. In the first case temperature cycling leads to the creation of extended fluid domains built around some of the initial fluid droplets. In the second case quenching into the demixed region leads to the formation of domains which reflect the demixing kinetics. The structures are stable due to a jammed, semisolid, multilayer of colloids on the liquid-liquid interface. The differing morphologies reflect the roles in formation of the arrested state of heterogeneous and homogeneous nucleation and spinodal decomposition. The latter results in metastable, bicontinuous emulsions with frozen interfaces, at least for the thin-slab samples, investigated here. 相似文献
189.
190.
The emergence of stock markets in former centrally planned economies poses a significant problem to financial economists and policy makers in that price movements in these markets are not well explained by conventional capital theory. The opening of stock markets brings about a new equilibrium value P̂ for the firm. Shares are floated on an estimate of P̂, and buyers of these shares and individuals trading in the secondary market are also obliged to do so on the basis of their estimates of this magnitude. At any time, the market price of the firm's shares then reflects the market's best guess of what its value would be in the new equilibrium, and information on which to calculate estimates become more readily available as the stock market matures. This paper presents a stochastic price model which takes all of these factors into consideration. The model also provides a theoretical foundation underlying the pronounced trends of prices in emerging stock markets, and explains why they appear to be so volatile. © 1998 John Wiley & Sons, Ltd. 相似文献