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91.
In 1914 Bohr proved that there is an r (0,1) such that if apower series converges in the unit disk and its sum has modulusless than 1 then, for |z| < r, the sum of absolute valuesof its terms is again less than 1. Recently, analogous resultshave been obtained for functions of several variables. The aimof this paper is to place the theorem of Bohr in the contextof solutions to second-order elliptic equations satisfying themaximum principle. 2000 Mathematics Subject Classification: 35J15, 32A05, 46A35. 相似文献
92.
In this paper, we classify all optimal linear[n, n/2] codes up to length 12. We show that thereis a unique optimal [10, 5, 5] code up to equivalence. 相似文献
93.
Beghin Luisa Knopova Viktoria P. Leonenko Nikolai N. Orsingher Enzo 《Journal of statistical physics》2000,99(3-4):769-781
We analyze the asymptotic behavior of the rescaled solution to the linear Korteweg–de Vries equation when the initial conditions are supposed to be random and weakly dependent. By means of the method of moments we prove the Gaussianity of the limiting process and we present its correlation function. The same technique is applied to the analysis of another third-order heat-type equation. 相似文献
94.
Stanislav V. Averin Petr I. Kuznetzov Victor A. Zhitov Nikolai V. Alkeev 《Optical and Quantum Electronics》2007,39(3):181-192
Solar-blind MSM photodetectors based on the AlGaN heterostructures have been fabricated and investigated. The influence of
material properties on device parameters is discussed. Effect of different buffer layers on the detector performances has
been examined. Detectors exhibit low dark currents and high sensitivity within the range of 250–290 nm. Effect of optical
excitation energy on GaN-based MSM-detector performance is analyzed and discussed. At high excitation level the detector speed
of response is limited by the field screening caused by the space-charge of the holes. The impulse response of GaN-based MSM-detector
is compared favorably with GaAs MSM-device. 相似文献
95.
An upper estimate for the Lempert function of any C
1+ε
-smooth bounded domain in
\mathbbCn{\mathbb{C}^n} is found in terms of the boundary distance. 相似文献
96.
Natalia A. Nikonorova Nikolai N. Smirnov Ricardo Diaz‐Calleja Alexander V. Yakimansky 《Journal of Polymer Science.Polymer Physics》2008,46(14):1488-1496
Local forms of molecular mobility of comb‐like random copolymethacrylates, containing side‐chain nonlinear optical chromophores and amyl‐ or octafluoroamyl‐groups, are studied. In the glassy state, two relaxation processes are found, which are due to reorientation of terminal polar groups (γ2‐process) and rotation of chromophore groups about their long axes (β‐process). For octafluoroamyl‐containing copolymers, the γ2‐process is superposition of the two molecular motions due to reorientation of terminal chromophore groups and ? CF2H groups. The intensity and relaxation times in the range of the γ2‐process depend on the chemical structure and concentration of chromophores in a copolymer. For the β‐process, the molecular mobility weakly depends on the chromophore structure, being mainly determined by the relative lengths of the rigid chromophore and flexible side chains. On the global spectrum of depolarization current it was observed the γ1‐process due to reorientation of (CH2)n spacers between chromophore groups and copolymer backbone. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1488–1496, 2008 相似文献
97.
Donald A. Ross Alexander H. Chu Thomas J. Nikolai Jon M. Ryan Donald G. Schaefer Andrew R. Schmidt 《Adsorption》1999,5(4):391-398
Continuous perfusion cell culture, using albumin containing medium, offers the potential advantages of higher recombinant Prourokinase (r-ProUK) yields, higher initial product purity and increased throughput compared to batch culture technology using medium supplemented with fetal bovine serum. We have characterized the production of r-ProUK in medium supplemented with a lipid rich bovine serum albumin (Albumax) in a perfusion system. The results of these studies showed that it was necessary to modify the r-ProUK batch recovery scheme to process r-ProUK from a perfusion system. To accommodate large volumes of perfusate harvested over a ten to fourteen day production cycle, cation exchange and hydrophobic interaction chromatography (HIC) resins were identified that had increased product binding capacity, better flow characteristics and wider pH ranges which allowed caustic cleaning. The mobile phase composition, pH and ionic strength were modified to improve r-ProUK yields from the identified resins, and procedures were developed to eliminate r-ProUK degradation products. Strategies were defined for processing continuous harvest, which contained four to seven times the amount of r-ProUK of batch harvests. 相似文献
98.
99.
100.
Kocherginsky NM Lvovich VF 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18209-18218
Earlier we have shown that many important properties of ionic aqueous channels in biological membranes can be imitated using simple biomimetic membranes. These membranes are composed of mixed cellulose ester-based filters, impregnated with isopropyl myristate or other esters of fatty acids, and can be used for high-throughput drug screening. If the membrane separates two aqueous solutions, combination of relatively hydrophilic polymer support with immobilized carboxylic groups results in the formation of thin aqueous layers covering inner surface of the pores, while the pore volume is filled by lipid-like substances. Because of these aqueous layers biomimetic membranes even without proteins have a cation/anion ion selectivity and specific (per unit of thickness) electrical properties, which are similar to typical properties of biological membranes. Here we describe frequency-dependent impedance of the isopropyl myristate-impregnated biomimetic membranes in the 4-electrode arrangement and present the results as Bode and Nyquist diagrams. When the membranes are placed in deionized water, it is possible to observe three different dispersion processes in the frequency range 0.1 Hz to 30 kHz. Only one dispersion is observed in 5 mM KH(2)PO(4) solution. It is suggested that these three dispersion features are determined by (a) conductivity in aqueous structures/channels, formed near the internal walls of the filter pores at high frequencies, (b) dielectric properties of the whole membrane at medium frequencies, determined by polymer support, aqueous layers and impregnating oil, and, finally, (c) by the processes in hydrated liquid crystal structures formed in pores by impregnating oil in contact with water at low frequencies. 相似文献