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We prove a Capelli type theorem on the canonical decomposition for multiplicative convolutions of polynomials. We derive then some irreducibility criteria for convolutions of polynomials in several variables over a given field. The irreducibility conditions are expressed only in terms of the degrees of the polynomials in convolution, the degrees of their coefficients, and the degrees of some suitable divisors of the resulting leading coefficient. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Monica Magureanu Daniela Piroi Florin Gherendi Nicolae Bogdan Mandache Vasile Parvulescu 《Plasma Chemistry and Plasma Processing》2008,28(6):677-688
The decomposition of methylene blue (MB) in aqueous solution was investigated using a pulsed corona discharge. The discharge
was ignited in the gas bubbled in the solution through several needle electrodes. The influence of treatment time, volume
of the treated solution and initial concentration of the dye in solution on MB degradation was studied. The effect of the
nature of the gas introduced was also investigated. For the same energy input, MB conversion increased in the order air < argon < oxygen.
When using oxygen, the decomposition of MB exceeded 95% after ~20 min plasma treatment. Higher efficiency was obtained for
higher treated volume and higher initial concentration. At 90% conversion the yield obtained with oxygen was ~5 g/kWh for
an initial concentration of 150 mg/l and a treated volume of solution of 100 ml. 相似文献
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J. J. A. Wijs G. D. Elsdon J. R. Stubbs H. Lührig H. Atkinson A. Azadian G. Spitzer F. W. Epple C. H. Manley H. S. Shrewsbury L. V. Cocks E. Nightingale L. Hoton D. W. Steuart P. Smith G. H. Leopold W. J. de Mooy G. van B. Gilmour S. H. Blichfeldt T. Thornley E. L. Smith H. P. Kaufmann E. R. Bolton und C. Revis 《Fresenius' Journal of Analytical Chemistry》1930,80(7-8):303-314
Ohne Zusammenfassung 相似文献
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Prader-Willi syndrome (PWS) is a multisystem disorder caused by DNA abnormalities involving chromosome 15. Major characteristics are infant hypotonia, hypogonadism, mental retardation, a short stature, atypical facial appearance, and the onset of obesity due to insatiable hunger in early childhood. Also, speech and language abnormalities have been reported including voice disorders. These have seldom been studied in detail, however. This paper reports the results of an acoustic and aerodynamic investigation of the voice in 22 individuals with PWS. Two age groups were distinguished, a group of children [chronological age (CA) 6 years, 7 months through 11 years, 7 months; total intelligence quotient (TIQ) 40-88] and a group of adolescents and adults (CA 17 years, 1 month through 29 years, 5 months; TIQ 41-94). Both aerodynamic and acoustic parameters were obtained and compared with normative data from the Belgian Study Group on Voice Disorders. It was found that voice difficulties do commonly occur in individuals with PWS including impairment of frequency levels, voice quality, and poor aerodynamic capabilities. 相似文献
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