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Zakharov A. V. Rozenko S. A. 《Journal of Communications Technology and Electronics》2019,64(4):430-438
Journal of Communications Technology and Electronics - Microstrip band-pass filters (BPFs) containing quarter-wavelength resonators and a Π-shaped half-wavelength resonator placed next to each... 相似文献
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SF Zakharov SH Kwok H Sokoloff HT Chang SP Radko A Chrambach 《Canadian Metallurgical Quarterly》1998,19(10):1625-1630
An automated gel electrophoresis apparatus, recently available commercially, allows one to follow the band during electrophoresis in real time, and lends itself therefore to an evaluation of bandwidth as a function of migration time (the dispersion coefficient), resolution and band shape. These determinations assume the constancy of band area with migration time and at various gel concentrations. The purpose of the present study was to verify these assumptions. Representative proteins and sodium dodecyl sulfate (SDS)-proteins, either natively fluorescent or fluorescein carboxylate labeled, were found to exhibit band areas which approach constancy as a function of migration time in both agarose and polyacrylamide gel electrophoresis, provided that (i) the protein concentration under the band was low enough to obviate self-quenching of fluorescence; (ii) the separation of the protein of interest from contaminants had progressed sufficiently during the time at which band areas were measured; (iii) the baseline under the peak was sufficiently well defined. However, band areas decrease with increasing gel concentration. Protein peaks exhibited leading and trailing tails. The ratio of the combined tail area to total area appeared to be near-constant at varying migration times. However, that ratio increases with increasing gel concentration. The tail area does not appear to be an artifact of fluorometric detection since it is reproduced upon fluorimetric analysis of the protein eluted from gel slices after electrophoresis. However, it may be due to photochemical destruction under the conditions of repetitive fluorometric peak detection. 相似文献
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Forty-seven children afflicted with acute leukemia were studied at the Tata Memorial Hospital Bombay to record the occurrence of oral manifestations prior to and during chemotherapy. Lymphadenopathy was the most frequent single finding suggestive of leukemia during head and neck examination. Gingival abnormalities, bleeding gums and oral mucosal pallor were the other findings on initial oral examination. Due to immunosuppression caused by the chemotherapy drugs oral mucosal ulcerations, uncontrolled herpes, candidiasis and pseudomoniasis were observed. 相似文献
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Alexey S. Matveev Andrey V. Savkin 《Mathematics of Control, Signals, and Systems (MCSS)》2002,15(2):120-144
This paper deals with qualitative analysis of the so-called switched fluid networks. Such networks are used to model communication,
computer, and flexible manufacturing systems. We prove that for any deterministic network from a specific class, there exists
a finite number of limit cycles attracting all the trajectories of the system. Furthermore, we determine this number.
Date received: March 11, 2000. Date revised: January 19, 2001. 相似文献
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Dynamics of a single fluxon in an annular Josephson junction is studied in the presence of an externally applied magnetic
field H. Due to the interaction of the fluxon with the radial field component, the fluxon moves in a potential well which
height is proportional to H. Several spectacular features of fluxon dynamics analogous to the motion of a particle in a washboard
potential are clearly observed experimentally. Periodic revolutions of the fluxon in the junction lead to a potential induced
emission of plasma waves. These waves are indicated by a resonance at a certain fluxon velocity which depends on the junction
length. Good agreement between experiment, theoretical model and numerical simulations is found. 相似文献