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51.
Son DT 《Physical review letters》2000,84(17):3771-3774
Using the Poisson bracket method, we construct the hydrodynamics of nuclear matter in the chiral limit, which describes the dynamics of all low-energy degrees of freedom, including the fluid-dynamical and pionic ones. The hydrodynamic equations contain, beside five Euler equations of relativistic fluid dynamics, N(2)(f)-1 second order equations describing propagating pions and N(2)(f)-1 first order equations describing the advection of the vector isospin charges. We present hydrodynamic arguments showing that the pion velocity vanishes at the second order phase transition at N(f) = 2. 相似文献
52.
We report stress dependence of growth characteristics of epitaxial γ-Na0.7CoO2 films on various substrates deposited by pulsed laser deposition method. On the sapphire substrate, the γ-Na0.7CoO2 thin film exhibits spiral surface growth with multi-terraces and highly crystallized texture. For the γ-Na0.7CoO2 thin film grown on the (1 1 1) SrTiO3 substrate, the nano-islands of ∼30 nm diameter on the hexagonal grains are observed. These islands indicate that the growth mode changes from step-flow growth mode to Stranski-Krastanow (SK) growth mode. On the (1 1 1) MgO substrate, the large grains formed by excess adatoms covering an aperture between hexagonal grains are observed. These experimental demonstrations and controllability could provide opportunities of strain effects of NaxCoO2, physical properties of thin films, and growth dynamics of heterogeneous epitaxial thin films. 相似文献
53.
Kyung Ah Jeon Hyo Jeong Son Chang Eun Kim Jong Hoon Kim Sang Yeol Lee 《Physica E: Low-dimensional Systems and Nanostructures》2007,37(1-2):222
ZnO nanowires were fabricated on c-plane (0 0 0 1), a-plane (1 1 2¯ 0) sapphire, and boron doped p-type (1 0 0) Si substrates in vacuum furnace by simple physical vapor deposition. Room temperature photoluminescence spectra of the nanowires show the near band-edge emission and the deep-level green light emission. The ZnO nanowires formed on sapphire (1 1 2¯ 0) substrates exhibited enhancement on optical properties and better crystalline structures than those of nanowires grown on other substrates. The formation mechanism and the effect of substrate direction on structural and optical properties of the nanowires are discussed. 相似文献
54.
We fabricated high quality epitaxial Bi0.9Ho0.1FeO3 thin films which exhibited the tetragonally stained structure with a c/a ratio of about 1.04. The Bi0.9Ho0.1FeO3 thin film showed a good ferroelectric property with the high remanent polarization (Pr) of about 80 μC/cm2. The ferromagnetic hysteresis loop with a clear remanent magnetization was shown. The coercive field and the remanent magnetization of the Bi0.9Ho0.1FeO3 film are 6200 Oe and 1.7 emu/g, respectively. The abrupt conduction due to space charge limited (SCL) was revealed in leakage current density versus electric field. 相似文献
55.
A new butenolide, designated odoratinolide (1), was isolated from the bark of the Vietnamese medicinal plant Machilus odoratissima. Its structure was determined by spectroscopic analyses. 相似文献
56.
Jae-Dong Son 《Queueing Systems》2008,60(1-2):71-85
We consider a discrete-time admission control problem in a company operating in service industries with two classes of customers. For the first class of customers, the company then (1) has an option to accept or reject him/her (admission control), or (2) decides on an offering price (pricing control). The second-class (sideline) customers are only served if no first-class customers are in the system, and this yields the sideline profit. In this paper, we discuss both admission control and pricing control problems within an identical framework, and we examine the properties of the optimal policies to maximize the total expected present discounted net profits. We show that when the sideline profit is large, the optimal policies may not be monotone in the number of first-class customers in the system. 相似文献
57.
Merritt Smith Kaitlyn Stambaugh Lauren Smith Hye-Jin Son Amanda Gardner Scott Cordova Krystal Posey Donald Perry Alexandru S. Biris 《Vibrational Spectroscopy》2009,49(2):288-297
Adsorption properties of acetylsalicylic acid (AA), ibuprofen and acetaminophen deposited from volatile solvents with varying protic/aprotic properties on vacuum-evaporated silver films were characterized using surface-enhanced infrared absorption (SEIRA) and surface-enhanced Raman spectroscopy (SERS). SERS preferentially enhances monolayer Raman shifts, while SEIRA can enhance the infrared absorbance of the monolayer and multilayers. To our best knowledge, this is the first reported study of these molecules using a combination of SERS/SEIRA. SERS revealed that AA and ibuprofen adsorbed ionically in monolayers, independent of the deposition solvents used in the process. SEIRA experiments showed that AA multilayers condensed molecularly using a deposition solvent with polar bonds. However, when an alkane deposition solvent with non-polar bonds such as n-heptane was used, AA adsorbed as acetylsalicylate ions in the first few multilayers, while ibuprofen always adsorbed as the free acid in the multilayer. These ionization trends depend upon the affinity of AA and ibuprofen for the underlying silver film. TPD experiments on silver powders further demonstrated that ibuprofen affinity for silver was less than AA. Furthermore, SEIRA indicated that acetaminophen adsorbed as multilayers of metastable polymorphs using protic or polar aprotic deposition solvents. Protic deposition solvents gave higher quality SERS spectra of an acetaminophen monolayer in comparison to polar aprotic deposition solvents. Such studies could find significant applications in biochemical and nanotechnology processes such as drug delivery, catalysis, and tissue engineering and will contribute to the understanding of the impact and fate of analgesics released into the environment. 相似文献
58.
Journal of Visualization - An unbalanced panel is a dataset in which at least one subject is not observed some times. Moreover, each subject is recorded with irregular periods and intervals.... 相似文献
59.
Gopalakrishnan Aridoss Min Sung Kim Se Mo Son Jong Tae Kim Yeon Tae Jeong 《先进技术聚合物》2010,21(12):881-887
Organic–inorganic composites composed of electrically conducting copolymer p‐phenylenediamine‐ co‐o‐aminophenol and carboxylic acid functionalized multi‐walled carbon nanotubes [poly(pPD‐co‐oAP)/c‐MWNTs] were prepared via in situ emulsion pathway using sodium dodecyl sulphate (SDS) as an emulsifier and potassium persulphate as an oxidant. Acid functionalized MWNTs were used as cores in the formation of tubular shells of the composites. TEM and FESEM analysis showed that a tubular layer of coated copolymer film of several nanometer thicknesses is present on the c‐MWNTs surfaces. FT‐IR spectra endorsed the formation of composites. TGA results indicated that the decomposition temperatures of composites were higher than the bare copolymer. UV‐visible absorption spectra of diluted colloidal dispersion of composites were similar to those of the bare copolymer. The composites were also confirmed by XRD and XPS. Room‐temperature conductivity increases with an increasing fraction of c‐MWNTs. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
60.