Ультрафиолетовое излучение импульсно–периодических разрядов высокого давления в ксеноне

Pulsed quartz-jacketed high-pressure xenon lamps, operating in the periodic pulse repetition modes, despite the appearing UV radiation sources of other types, remain a critical component of the processing equipment used in photochemistry, photo-medicine, nanoelectronics, biology, etc. Their main advantages, namely high power and radiation energy are slightly devalued by a relatively low efficiency of the shortwave radiation. Available literature data concerning the influence of various factors on the energy level of short-wave radiation in xenon need to be systematised and generalised because they have been obtained under conditions of uncontrolled quartz-jacketed transmission. The transmission of quartz can degrade after a while and, in addition, undergo great changes during the pulse. Besides, as a rule, in the literature, there is no detailed description of a complete kit of experimental setting. As a result, to analyse the factors affecting the efficiency of studying in the UV range is difficult, and there arises a relevant problem to optimise this type of discharge parameters to increase the efficiency in the range of 220-400 nm. A mathematical model of the radiation source, realistically describing the processes in the xenon plasma and in the stabilising envelope, can be a reliable ground for such a study. The paper shows an impact of the discharge channel diameter and length, the filling pressure of xenon, the pulse duration, the parameters of discharge circuit, and the current of pilot arc on the radiation yield. Based on the simulation-found relationship of internal plasma parameters (temperature distributions, fields of particle concentration and radiation, dynamics of electrical resistance of discharge channel, and plasma emission spectra) with radiation characteristics of discharge, are determined conditions to ensure the greatest radiation yield in the UV region.  The experimental data prove the computational results. A material obtained gives practice-critical guidelines for development and correct selection of the short-wave radiation source.Импульсные ксеноновые лампы высокого давления в кварцевой оболочке, работающие в режимах периодического следования импульсов, несмотря на появление источников УФ- излучения других типов остаются важнейшим компонентом технологического оборудования, применяемого в фотохимии, фотомедицине, наноэлектронике, биологии и т.д. Главные их достоинства -  высокая мощность и энергия излучения - несколько обесценивает относительно низкая эффективность излучения в коротковолновой области. Имеющиеся литературные данные о влиянии различных факторов на уровень энергии коротковолнового излучения разрядов в ксеноне нуждаются в систематизации и обобщении, т.к. они получены в условиях неконтролируемого значения пропускания кварцевой оболочки. Пропускание кварца может деградировать со временем и, кроме того,  сильно меняться в течение импульса. Кроме того,  в литературе отсутствует, как правило, детальное описание полного набора условий проведения эксперимента. В итоге анализ факторов, влияющих на  эффективность изучения в УФ- области затруднен, и возникает актуальная задача оптимизации параметров разрядов указанного типа с целью увеличения КПД в области 220-400 нм. Надежной основой для проведения такой работы может служить расчетно- теоретическое исследование с помощью  математической модели источника излучения, реалистично описывающей процессы в плазме ксенона и стабилизирующей оболочке. В работе  показано влияние на  выход излучения диаметра и длины разрядного канала, давления наполнения ксенона, длительности импульса, параметров разрядного контура, тока дежурной дуги. На основе устанавливаемой при моделировании связи внутренних параметров плазмы (температурных распределений, полей концентрации частиц и радиации, динамики электрического сопротивления канала разряда и спектров излучения плазмы) с радиационными характеристиками разряда определены условия, обеспечивающие наибольший выход излучения в УФ- области. Результаты вычислений  подтверждены экспериментальными данными. Полученныйматериал дает важные для практики ориентиры для разработки и правильного выбора источника излучения коротковолнового диапазона

MAGNETIZED PLASMA PARAMETRIC RESONANCE IN NON-MONOCHROMATIC PUMP-WAVE

No abstract availabl

Ultraviolet Radiation of Repetitively Pulsed High-pressure Discharges in Xenon

Pulsed quartz-jacketed high-pressure xenon lamps, operating in the periodic pulse repetition modes, despite the appearing UV radiation sources of other types, remain a critical component of the processing equipment used in photochemistry, photo-medicine, nanoelectronics, biology, etc. Their main advantages, namely high power and radiation energy are slightly devalued by a relatively low efficiency of the shortwave radiation. Available literature data concerning the influence of various factors on the energy level of short-wave radiation in xenon need to be systematised and generalised because they have been obtained under conditions of uncontrolled quartz-jacketed transmission. The transmission of quartz can degrade after a while and, in addition, undergo great changes during the pulse. Besides, as a rule, in the literature, there is no detailed description of a complete kit of experimental setting. As a result, to analyse the factors affecting the efficiency of studying in the UV range is difficult, and there arises a relevant problem to optimise this type of discharge parameters to increase the efficiency in the range of 220-400 nm. A mathematical model of the radiation source, realistically describing the processes in the xenon plasma and in the stabilising envelope, can be a reliable ground for such a study. The paper shows an impact of the discharge channel diameter and length, the filling pressure of xenon, the pulse duration, the parameters of discharge circuit, and the current of pilot arc on the radiation yield. Based on the simulation-found relationship of internal plasma parameters (temperature distributions, fields of particle concentration and radiation, dynamics of electrical resistance of discharge channel, and plasma emission spectra) with radiation characteristics of discharge, are determined conditions to ensure the greatest radiation yield in the UV region.  The experimental data prove the computational results. A material obtained gives practice-critical guidelines for development and correct selection of the short-wave radiation source

Ultrasonic Intensification of Mass Transfer in Organic Acid Extraction

The mechanism of ultrasonic extraction was discovered and analyzed in detail for the liquid membrane technique from the consideration of the specific features of the radial vibrations of a droplet of the dispersed phase placed into an immiscible continuous phase subjected to ultrasonic irradiation. Analytical formulas were derived for the rate of mass transfer as a function of the amplitude of acoustic pressure oscillations and the time of ultrasonic treatment of an extraction system. Conditions for achieving the maximum efficiency of the extraction of a substance under the stimulating effect of ultrasound were analyzed. A nonlinear equation was derived for the radial vibrations of a spherical droplet of the dispersed phase in an immiscible continuous phase under forcing in the form of acoustic pressure periodically changing with time. Experimental study of the dependence of sulfosalicylic acid distribution on time in an aqueous two-phase system with ultrasound shows good agreement of experimental results with the calculations performed

Modelling of the Erosive Dissolution of Metal Oxides in a Deep Eutectic Solvent—Choline Chloride/Sulfosalicylic Acid—Assisted by Ultrasonic Cavitation

Here we report on the results concerning the influence of ultrasound on the dissolution process of metal oxides CoO, Ni2O3 and Mn2O3 in choline chloride/sulfosalicylic acid as a deep eutectic solvent. The mechanism of dissolution under cavitation conditions with ultrasonic assistance is described. Theoretical research resulted in equations describing the dissolution process kinetics and linking its basic parameters. Optimal conditions for the most effective ultrasound application were found. Experimental data on dissolution kinetics of metal oxides in deep eutectic solvents was also obtained. It was discovered that experimental data correlates well with theoretical calculations, which confirms the correctness of developing a picture about the physicochemical nature of the process under study

Correction of the recording artifacts and detection of the functional deviations in ECG by means of syndrome decoding with an automatic burst error correction of the cyclic codes using periodograms for determination of code component spectral range

Aims This paper describes a novel approach to the analysis of electrocardiographic data based on the consideration of the repetitive P, Q, R, S, T sequences as cyclic codes. In Part I we introduce a principle similar to the syndrome decoding using the control numbers, which allows correcting the noise combinations. Materials and methods We propose to apply the burst-error-correcting algorithms for automatic detection of the ECG artifacts and the functional abnormalities, including those compared to the reference model. Our approach is compared to the symbolic dynamics methods. During the automated search of the code components (i.e. point values and spectral ranges one-to-one corresponding to P, Q, R, S, T) considered in Part II, the authors apply the Lomb-Scargle periodogram method with the phase control which allows to determine the code components not only from the main harmonics, but also using the sidebands, avoiding the phase errors. Results The results of the method testing on rats with the heart failure using a simplified telemetric recording from the implantable chips are given in Part III. A complete independence of the results of the determination of the code points (fingerprints) from the variables for which the calculation is performed is shown. We also prove the robustness of the above approach with respect to the most types of the non-adaptive filtration. Conclusion The above method can be useful not only for experimental medicine, but also for veterinary and clinical diagnostic practice. This method is adequately reproduced both on animals and human ECG, except for some constant values