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101.
We improve the fermion tunnelling theory proposed by Kerner and Mann, and research into the fermion tunnelling radiation from a Finslerian black hole. The Finsler black hole put forward by Rutz is a solution of Einstein's vacuum field equations in Finsler theory. We study the radiation from the black hole with a semi-classical method, and the result proves that the tunnelling rate depends on the tangent vector. 相似文献
102.
We present a theoretical model for the evolution of mixture concentrations in a micro-pervaporation device, similar to those
recently presented experimentally. The described device makes use of the pervaporation of water through a thin PDMS membrane
to build up a solute concentration profile inside a long microfluidic channel. We simplify the evolution of this profile in
binary mixtures to a one-dimensional model which comprises two concentration-dependent coefficients. The model then provides
a link between directly accessible experimental observations, such as the widths of dense phases or their growth velocity,
and the underlying chemical potentials and phenomenological coefficients. It shall thus be useful for quantifying the thermodynamic
and dynamic properties of dilute and dense binary mixtures. 相似文献
103.
Fei Yu Molin Liu Yuanxing Gui 《The European Physical Journal C - Particles and Fields》2009,60(2):175-179
We employ the metric of Schwarzschild space surrounded by quintessential matter to study the trajectories of test masses on
the motion of a binary system. The results, which are obtained through the gradually approximate approach, can be used to
search for dark energy via the difference of the azimuth angle of the pericenter. The classification of the motion is discussed. 相似文献
104.
Molin Liu Jianbo Lu Yuanxing Gui 《The European Physical Journal C - Particles and Fields》2009,59(1):107-116
On the basis of the 4D momentum, the influence of quintessence on the gravitational frequency shift and the deflection of
light are examined in modified Schwarzschild space. We find that the frequency of a photon depends on the state parameter
of the quintessence w
q: the frequency increases for −1<w
q<−1/3 and decreases for −1/3<w
q<0. Meanwhile, we adopt an integral power number a (a=3ω
q+2) to solve the orbital equation of photon. The photon’s potentials become higher with the decrease of ω
q. The behavior of the bending light sensitively depends on the state parameter ω
q. In particular, for the case of ω
q=−1, there is no influence on the deflection of light by quintessence. Furthermore, according to the H-masers of the GP-A
redshift experiment and long-baseline interferometry, the constraints on the quintessence field in the solar system are presented
here. 相似文献
105.
We study perturbations of black holes absorbing dark energy. Due to the accretion of dark energy, the black hole mass changes. We observe distinct perturbation behaviors for absorption of different forms of dark energy onto the black holes. This provides the possibility of extracting information whether dark energy lies above or below the cosmological constant boundary w=−1. In particular, we find in the late time tail analysis that, differently from the other dark energy models, the accretion of phantom energy exhibits a growing mode in the perturbation tail. The instability behavior found in this work is consistent with the Big Rip scenario, in which all of the bound objects are torn apart with the presence of the phantom dark energy. 相似文献
106.
Sybille Hopman Andreas Fell Kuno Mayer Matthias Mesec Andreas Rodofili Daniel Kray 《Applied Physics A: Materials Science & Processing》2009,95(3):857-866
This paper deals with the development of a new cutting method for thin silicon solar wafers with liquid-jet-guided lasers (LaserMicroJet®, LMJ, and Laser Chemical Processing, LCP). Several laser systems with different wavelengths were tested to find the optimum laser system and processing parameters in terms of efficient material removal and deep laser cutting. Water and potassium hydroxide were used as carrier liquids to enhance laser ablation. The ablation efficiency was defined as a target parameter and experimentally determined by performing single laser grooves. It is demonstrated that the ablation process of LMJ is mainly affected by silicon melting and then removing by the liquid-jet momentum for single laser grooves. Best result for deep laser grooves is achieved if evaporation dominates the ablation process. Better surface quality referred to laser-induced crystalline damage is presented for a cut wafer with LMJ in comparison to a standard multiwire slurry saw. This shows a great potential of wafering with liquid-jet-guided lasers although no optimal liquid media was used. 相似文献
107.
Yew Von Lim Haiming Fan Zexiang Shen Chiang Huen Kang Yuanping Feng Shijie Wang 《Applied Physics A: Materials Science & Processing》2009,95(2):555-562
The silica supported titania nanocomposite thin films with controllable particle size and phase content were successfully
prepared by a convenient post annealing approach involving in solid-solid interfacial reaction. The effects of growth conditions,
such as the annealing temperature and silicon concentration on the particle size and phase content, were systematically studied
by using Atomic force microscopy (AFM), Raman spectroscopy, X-ray diffraction (XRD), and X-ray spectroscopy (XPS). The results
indicate that the silicon concentration is a dominant factor in the morphology, crystallization and phase transformation of
these nanocomposites. A mechanism for the high temperature phase transformation is also proposed based on the migration of
the oxygen vacancies. 相似文献
108.
We describe a microfluidic all-optical technique to measure the thermophoresis of molecules. Within micrometer-thick chambers, we heat aqueous solutions with a micrometer-sized focus of infrared light. The temperature increase of about 1 K is monitored with temperature-sensitive fluorescent dyes. We test the approach in measuring the thermophoresis of DNA. We image the concentration of DNA in a second fluorescence-color channel. DNA is depleted away from the heated spot. The profile of depletion is fitted by the thermophoretic theory to reveal the Soret coefficient. We evaluate the method with numerical 3D calculations of temperature profiles, drift, convection and thermophoretic depletion using finite element methods. The approach opens new ways to monitor thermophoresis at the single molecule level, near boundaries and in complex mixtures. The flexible microfluidic setting is a good step towards microfluidic applications of thermophoresis in biotechnology. 相似文献
109.
Ch. Krauns M. Sumida M. Tagami Y. Yamada Y. Shiohara 《Zeitschrift für Physik B Condensed Matter》1994,96(2):207-212
The liquidus compositions of Y, Sm, Gd, Dy and Yb for a melt with a Ba to Cu ratio of 3 to 5 has been investigated by a) dipping thermally equilibrated (held in the furnace for at least 10 min) MgO single crystals into the melt and analyzing the melt stuck to the MgO by ICP; b) dipping a relatively cool not thermally equilibrated Al2O3 polycrystalline rod into the melt (i.e. effective quenching) and analyzing the melt stuck to the rod by ICP. The measurements have been made in the temperature range from approximately 950° C up to about 1300° C. Following thermodynamic calculations, expressions for the liquidus lines are derived and the enthalpy of dissolution for the various RE123 and RE211 are calculated to be nearly the same for the same melt composition. Nevertheless a small increase of the enthalpy of dissolution with increasing peritetic temperature could be detected. 相似文献
110.
To explore an effect of temperature on the dielectric properties in polyaniline/poly(vinylidene fluoride) (PANI/PVDF) composites, the dielectric properties of these composites with different volumetric fractions of PANI (?PANI) were studied in a wide temperature range. An increase in the effective conductivity (σeff) and dielectric permittivity (?eff) was observed with increasing temperature in all PANI/PVDF composites. Particularly, for the composite with ?PANI = 0.01, less than the percolation threshold (?C = 0.045), the increase in σeff and ?eff was most significant. A tunneling effect could be responsible for the unique dielectric properties. The results provided us useful information related to the microstructure of composites, which was not reported previously. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献