کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1269615 1496882 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Sensitivity of free radicals production in acoustically driven bubble to the ultrasonic frequency and nature of dissolved gases
ترجمه فارسی عنوان
حساسیت تولید رادیکال های آزاد در حباب های آکوستیکی منجر به فرکانس اولتراسونیک و ماهیت گازهای حل شده
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی (عمومی)
چکیده انگلیسی

Central events of ultrasonic action are the bubbles of cavitation that can be considered as powered microreactors within which high-energy chemistry occurs. This work presents the results of a comprehensive numerical assessment of frequency and saturating gases effects on single bubble sonochemistry. Computer simulations of chemical reactions occurring inside a bubble oscillating in liquid water irradiated by an ultrasonic wave have been performed for a wide range of ultrasonic frequencies (213–1100 kHz) under different saturating gases (O2, air, N2 and H2). For O2 and H2 bubbles, reactions mechanism consisting in 25 reversible chemical reactions were proposed for studying the internal bubble-chemistry whereas 73 reversible reactions were taken into account for air and N2 bubbles. The numerical simulations have indicated that radicals such as OH, H, HO2 and O are created in the bubble during the strong collapse. In all cases, hydroxyl radical (OH) is the main oxidant created in the bubble. The production rate of the oxidants decreases as the driving ultrasonic frequency increases. The production rate of OH radical followed the order O2 > air > N2 > H2 and the order becomes more remarkable at higher ultrasonic frequencies. The effect of ultrasonic frequency on single bubble sonochemistry was attributed to its significant impact on the cavitation process whereas the effects of gases were attributed to the nature of the chemistry produced in the bubble at the strong collapse. It was concluded that, in addition to the gas solubility, the nature of the internal bubble chemistry is another parameter of a paramount importance that controls the overall sonochemical activity in aqueous solutions.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ultrasonics Sonochemistry - Volume 22, January 2015, Pages 41–50
نویسندگان
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