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981.
蔡海涛 《数学物理学报(B辑英文版)》1995,(2)
TWOBOUNDEDHALFORTHOTROPICPLANEMATERIALSWITHCRACKSCaiHaitao(蔡海涛)(CentralSouthUniversityofTechnology,Changsha410083,China)Abstr... 相似文献
982.
Nguyen Ba Chanh Christian Hauw Alain Meresse Madeleine Rey-Lafon Laure Ricard 《Journal of Physics and Chemistry of Solids》1985,46(12):1413-1420
The existence of three main crystalline phases (called III, II and I) in (C12H25NH3)2CdCl4 has been revealed by differential scanning calorimetry. X-ray diffraction and spectroscopic studies. The crystal- lographic evolution with increasing temperature appears to be monoclinic (III) → orthorhombic (II) → tetragonal (I). The low temperature phase III is the only ordered structure. The phase transition (III-II), which is of first order type, corresponds to an order-disorder mechanism involving the organic part of the structure (alkylammonium chains) whereas the phase transition (II-I), which is of second-order type, is related to the arrangement of the mineral matrix (octahedra of perovskite layers). An intermediate disordered form II', stable in a very narrow temperature range and structurally similar to the form II, has also been observed, so that the transformation (III-II) proceeds, in fact, in two steps (III-II'-II). The variation enthalpies observed at the transitions (III-II'-II) and analyzed through an order-disorder mechanism demonstrate the high disorder of the alkylammonium chains in form II, in agreement with spectroscopic results. No thermal anomaly or spectroscopic modification is observed for the high temperature transition (II-I). 相似文献
983.
William R. Folks Sidhartha K. Pandey Greg Pribil Dennis Slafer Monis Manning Glenn Boreman 《International Journal of Infrared and Millimeter Waves》2006,27(11):1553-1571
High resolution reflective ellipsometry is used to study freely suspended plastic films. We determine room temperature optical
constants in the infrared for a variety of plastics using ellipsometry. The films are typically 6 to 100 μm thick and measurements
are performed from near infrared to long wave-IR. The setup includes modeling software to fit the ellipsometric data to a
generalized oscillator model. The films studied include acrylics, fluoropolymers, and variations of polyethylene, polystyrene,
and polyvinyl chloride (PVC) among others. We are able to determine in-plane and out-of-plane optical constants. Transmission
spectra from FTIR measurements are plotted and compared with ellipsometry results. 相似文献
984.
Integral curves of characteristic vector fields of real hypersurfaces in nonflat complex space forms
In this paper, we study real hypersurfaces all of whose integral curves of characteristic vector fields are plane curves in
a nonflat complex space form.
相似文献
985.
Within the framework of nonrelativisitic quantum electrodynamics we consider a single nucleus and N electrons coupled to the radiation field. Since the total momentum P is conserved, the Hamiltonian H admits a fiber decomposition with respect to P with fiber Hamiltonian H(P). A stable atom, respectively ion, means that the fiber Hamiltonian H(P) has an eigenvalue at the bottom of its spectrum. We establish the existence of a ground state for H(P) under (i) an explicit bound on P, (ii) a binding condition, and (iii) an energy inequality. The binding condition is proven to hold for a heavy nucleus and the energy inequality for spinless electrons. 相似文献
986.
L. Wang V.I. Perevalov S.A. Tashkun B. Gao L.-Y. Hao 《Journal of Molecular Spectroscopy》2006,237(2):129-136
The absorption spectrum of the natural sample of nitrous oxide has been recorded at Doppler limited resolution with a Fourier-transform spectrometer in the spectral range 5000-10 000 cm−1. Ten cold bands (8Σ − Σ and 2Σ − Π), thirteen hot bands (11Π − Π, Σ − Σ, and Δ − Δ) of 14N216O and the 3ν3 band of 14N15N16O have been newly detected. The uncertainty of the line position determination is estimated to be about 0.005 cm−1 for unblended lines. The assignment of the spectrum has been done with the help of the prediction performed within the framework of the polyad model of effective Hamiltonian. The spectroscopic parameters Gv, Bv, Dv, Hv, and qv have been determined for all newly detected bands. The line intensities of 13 weak bands have been measured. The uncertainty of the obtained line intensity values varies from 7 to 13%. 相似文献
987.
Batrice Vedel 《Applied and Computational Harmonic Analysis》2006,21(3):305-323
The Mumford process X is a stochastic distribution modulo constant and cannot be defined as a stochastic distribution invariant in law by dilations. We present two expansions of X—using wavelet bases—in X=X0+X1 which allow us to confine the divergence on the “small term” X1 and which respect the invariance in law by dyadic dilations of the process. 相似文献
988.
Mohammed Omar Keng Chuah Kozo Saito Akira Numasato Masahito Sakakibara 《Infrared Physics & Technology》2006,48(3):240-248
This paper describes a newly-developed automated thermal system for detection of seeds on newly painted car shells. The system’s novel approach is to use thermal emission; previously applied techniques relied on light reflection strategies. The system is described beginning with analytical modeling of the underlying detection theory to verification on a pilot run in an automotive production line. Parker’s flash procedure, using a thermal detector, was performed to extract the thermal properties of inspected panels. New computer logic developed in-house for processing the acquired thermograms is also presented. 相似文献
989.
Tamerlan T. Magkoev 《Surface science》2007,601(14):3143-3148
Interaction of carbon monoxide and oxygen on the surface of titania/Au(1 1 1) inverse model catalyst held at 200 K has been studied by reflection absorption infrared spectroscopy. It was found that CO adsorbs on the oxide/Au perimeter interface, whereas no or very weak adsorption was observed on Au(1 1 1) or titania surface, respectively. Exposing of such species to oxygen results in their decay possibly due to carbon dioxide formation. Efficiency of this effect is higher at lower CO initial concentration which points at the importance of free surface sites for the reaction process. 相似文献
990.
We have studied self-assembled monolayers (SAMs) of asymmetric dialkyldisulfide derivatives of the form CH3-(CH2)11+m-S-S-(CH2)11-OH with m = −4, −3, 0, +2 and +4 on gold. Sub-nanoscale changes in the length of the CH3-terminated alkylchain have been used to selectively protrude one particular end group in the resulting film. The alteration of the chain length in only two methylene units already results in changes of surface properties, which have been detected with local (chemical force microscopy) and macroscopic (contact angle) techniques. In particular, advancing contact angles can be adjusted between 40° and 80°. The adhesion between a hydrophobic tip and these SAMs in water is determined by the chemical nature of the protruding end group. Chemical force microscopy, X-ray photoelectron spectroscopy and infrared reflection absorption spectroscopy have shown that these SAMs are composed of mixed, well-packed CH3- and OH-alkylthiolate branches. The surface composition ratio is close to 1:1 for all investigated SAMs. 相似文献