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121.
Yu. A. Kumzerov L. S. Parfen’eva I. A. Smirnov H. Misiorek J. Mucha A. Jezowski 《Physics of the Solid State》2003,45(1):57-60
The thermal conductivity of crystalline chrysotile asbestos made up of hollow tubular Mg3Si2O5(OH)4 filaments is measured in the range 5–300 K. The paper discusses the possibility of using this material in studies of the thermal conductivity of thin filaments of metals and semiconductors incorporated into the channels of crystalline chrysotile asbestos tubes. 相似文献
122.
We provide a rigorous derivation of an asymptotic formula for perturbations in the eigenvalues caused by the presence of a finite number of inhomogeneities of small diameter with conductivity different from the background conductivity. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
123.
The Belavkin equation, describing the continuous measurement of the position of a quantum particle, is studied. A rigorous
representation of its solution by means of an infinite dimensional oscillatory integral (Feynman path integral) defined on
the complex Cameron-Martin space is given.
Received: 7 January 2002 / Revised version: 20 June 2002 / Published online: 19 December 2002
Mathematics Subject Classification (2000): 81, 81S40, 60H15
Key words or phrases: Belavkin equation – Continuous measurement – Quantum theory – Oscillatory integrals – Feynman path integrals 相似文献
124.
D. Amutha Rani Y. Yamamoto S. Mohri M. Sivakumar Y. Tsujita H. Yoshimizu 《Journal of Polymer Science.Polymer Physics》2003,41(3):269-273
In this study, a novel stepwise extraction method has been examined. The guest molecules housed between the helices of the clathrate δ form of syndiotactic polystyrene can be removed completely with this method. A systematic study of the preparation of a solvent‐free mesophase (emptied clathrate) membrane, its helical and residual solvent contents, and its structural transformations has been performed. In this first attempt, an enhancement in the TTGG helical content has been observed in the extracted membrane, and a conceptual mechanism is proposed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 269–273, 2003 相似文献
125.
126.
V. Bradnova M. M. Chernyavsky L. Just S. P. Kharlamov A. D. Kovalenko M. Haiduc K. A. Kotel’nikov V. A. Krasnov V. G. Larionova F. G. Lepekhin A. I. Malakhov G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova N. A. Salmanova B. B. Simonov S. Vokal P. I. Zarubin 《Physics of Atomic Nuclei》2003,66(9):1646-1650
A physical program of irradiation of emulsions in beams of relativistic nuclei named the BECQUEREL Project is reviewed. It is destined to study in detail the processes of relativistic fragmentation of light radioactive and stable nuclei. The expected results would make it possible to answer some topical questions concerning the cluster structure of light nuclei. Owing to the best spatial resolution, the nuclear emulsions would enable one to obtain unique and evident results. The most important irradiations will be performed in the secondary beams of He, Be, B, C, and N radioactive nuclei formed on the basis of JINR Nuclotron beams of stable nuclei. We present results on the charged state topology of relativistic fragmentation of the 10B nucleus at low energy-momentum transfers as the first step of the research. 相似文献
127.
K.S. Govinder 《Journal of Mathematical Analysis and Applications》2003,287(2):399-404
Linear nth order (n?3) ordinary differential equations have been shown to possess n+1, n+2 or n+4 Lie point symmetries. Each class contains equations which are equivalent under point transformation. By taking the example of third order equations, we show that all linear equations are equivalent if the class of transformation is broadened to include nonlocal transformations and hence the representative of this class of equations is y(n)=0. 相似文献
128.
David S. McGuinness Edward L. Marshall Vernon C. Gibson Jonathan W. Steed 《Journal of polymer science. Part A, Polymer chemistry》2003,41(23):3798-3803
Hetero‐bimetallic Fe(II) alkoxide/aryloxides were evaluated as initiators for the ring‐opening polymerization of rac‐lactide. [(THF)NaFe(OtBu)3]2 ( 1 ) and [(THF)4Na2Fe(2,6‐diisopropylphenolate)4] ( 2 ) (THF = tetrahydrofuran) both polymerized lactide efficiently at room temperature, with complex 1 affording better control over the molecular weight parameters of the resultant polymer. At conversions below 70%, a linear increase in molecular weight with conversion was observed, indicative of a well‐controlled polymerization process. Complex 2 is the first example of a dianionic Fe(II) alkoxide and has been structurally characterized to reveal a distorted square planar FeO4 array in which both Na counterions bridge two aryloxide ligands and are further complexed by two THF ligands. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3798–3803, 2003 相似文献
129.
The surface of hydrogen-sensitive GaAs Schottky diodes is modified by nonpolishing etching and by producing quantum wells and quantum dots in the space-charge region of the semiconductor. The sensitivity to hydrogen is found to increase by a factor of 8–37 after the etching and by two or three orders of magnitude after the introduction of quantum wells and dots. It is shown that the increased sensitivity is associated with the lowering of the barrier at the Pd/GaAs interface, the retardation of hydrogen diffusion into GaAs due to the presence of strained quantum-size layers, and an increase in the recombination current. The presence of the recombination component is supported by luminescence from the quantum wells and quantum dots, as well as from the GaAs substrate. The etch composition is shown to be a decisive factor in raising the sensitivity. 相似文献
130.
In this paper we consider the numerical approximation of steady and unsteady generalized Newtonian fluid flows using divergence free finite elements generated by the Powell–Sabin–Heindl elements. We derive a priori and a posteriori finite element error estimates and prove convergence of the method of successive approximations for the steady flow case. A priori error estimates of unsteady flows are also considered. These results provide a theoretical foundation and supporting numerical studies are to be provided in Part II. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献