An investigation of film wavy structure in annular flow using two simultaneous LIF approaches

The paper is devoted to development and validation of film thickness measurement techniques in interfacial gas-liquid flows. The specific flow investigated here is that of downwards (co-flowing) annular flow in a vertical pipe, however, many of the observations and findings are transferable to similar flow geometries. Two advanced spatially resolved techniques, namely planar laser-induced fluorescence and brightness-based laser-induced fluorescence , are used simultaneously in the same area of interrogation. A single laser sheet is used to excite fluorescence along one longitudinal section of the pipe, and two cameras (one for each method) are placed at different angles to the plane of the laser sheet in order to independently recover the shape of the interface along this section. This allows us to perform a cross-validation of the two techniques and to analyse their respective characteristics, advantages and shortcomings

An investigation of film wavy structure in annular flow using two simultaneous lif approaches

The paper is devoted to development and validation of film thickness measurement techniques in interfacial gas-liquid flows. The specific flow investigated here is that of downwards (co-flowing) annular flow in a vertical pipe, however, many of the observations and findings are transferable to similar flow geometries. Two advanced spatially resolved techniques, namely planar laser-induced fluorescence and brightness-based laser-induced fluorescence, are used simultaneously in the same area of interrogation. A single laser sheet is used to excite fluorescence along one longitudinal section of the pipe, and two cameras (one for each method) are placed at different angles to the plane of the laser sheet in order to independently recover the shape of the interface along this section. This allows us to perform a cross-validation of the two techniques and to analyse their respective characteristics, advantages and shortcomings.Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016

The investigation of hydrogen accumulation in zirconium alloy by thermostimulated gas evolution method

Thermostimulated gas evolution from zirconium alloy saturated by hydrogen E_125 versus deformation degree has been studied. Samples of zirconium were subjected to straining with relative lengthening 2,5; 5,0 and 10,0 %, then they were saturated with hydrogen by electrolyte method at current density 0,5 A/sm2 during 4 hours. Or vice versa, they were first saturated with hydrogen being subjected to deformation afterwards. The deformation of alloy samples results in trap formation with different energies of hydrogen bond. In this case both bond energy and hydrogen quantity caught in traps depends on both deformation size and succession of «deformation-saturation» actions. The values of hydrogen bond energies in traps are estimated. Types of traps are defined

Hemodynamic disorders in twin newborns in early neonatal period

Objectives: to show the relationship between heart disfunction and hemostasis disorders in twin newborns. Methods: the echocardiographic and hemostatic assessment were performed in 40 twin newborns (bichorial twins -1st group) and 40 twin newborns (monochorionic twins — 2d group). 30 term singleton newborn infants were included in the comparison group. All newborns were investigated in early neonatal period. Clinical parameters, anamnestic history, hemostatic and echocardiographic data were assessed. Results: the relationship between echoCG parameters of contractile and pump function and changes of rheological parameters was demonstrated in newborn twins. Conclusion: twin newborns are in group risk for heart disfunction and rheological disorders in early neonatal period. The depression of the heart contractile and pump function was demonstrated. These newborns have lower coagulation and fibrinolitic potentials and could be considered as risk group on hemorrhagic complications in early neonatal period.Цель работы: показать взаимосвязь нарушений дисфункции сердца и гемостаза в раннем неонатальном периоде у новорожденных двоен путем зхокардиографии и исследования системы гемостаза. Материалы и методы: обследовано 40 детей из бихориальных двоен (I группа) и 40 детей из монохориальных двоен (II группа). В группу сравнения вошли 30 доношенных новорожденных детей. Дети были обследованы в течение раннего неонатального периода. Оценивались анамнестические, клинические, гемостазиологические, эхокардиографические показатели. Результаты: в результате исследования выявлено зависимость между изменением параметров сократительной и насосной функций сердца и нарушением реологии крови у новорожденных двоен. Выводы: новорожденные из двое являются группой высокого риска по формированию нарушений работы сердца и реологических свойств крови в раннем неонатальном периоде. В этом периоде наблюдается депрессия сократительной и насосной функций сердца у новорожденных из двоен. Дети из монохориальных двоен имеют более низкий свертывающий и фибринолитический потенциал и соответственно составляют группу риска по развитию геморрагических осложнений в раннем неонатальном периоде

КЛИНИЧЕСКОЕ СОСТОЯНИЕ И ХЕМИЛЮМИНЕСЦЕНТНАЯ АКТИВНОСТЬ НЕЙТРОФИЛЬНЫХ ГРАНУЛОЦИТОВ БОЛЬНЫХ РАСПРОСТРАНЕННЫМ ГНОЙНЫМ ПЕРИТОНИТОМ В ДИНАМИКЕ ПОСЛЕОПЕРАЦИОННОГО ПЕРИОДА

The aim of this study was to evaluate the clinical condition and to study the chemiluminescent activity of granulocytes of patients with widespread purulent peritonitis in the dynamics of post-operative treatment. The severity of the patients was determined by the SAPS scale, the presence of systemic inflammatory response syndrome was assessed by the criteria of the ACCP/SCCM. Severity and prognosis of the disease was evaluated using the Mannheim peritonitis index and the index of abdominal cavity. The severity of multiple organ failure at admission to the hospital and in postoperative period dynamics were determined by the scale of the SOFA. The study of lucigenin- and luminal-dependent chemiluminescence of neutrophils in peritonitis were taken on admission to the hospital, and on the 7th, 14th and 24th day of the postoperative period. There were a variety of systemic complications (tertiary peritonitis, perforation of hollow organs, abscesses of the abdominal cavity and other) in patients with widespread purulent peritonitis 2nd severity in 96,2% of cases. The mortality rate among patients amounted to 22.2%. It was found in the study of neutrophils chemiluminescent activity that intensity of the “respiratory burst” in pre- and postoperative periods in patients with peritonitis is defined mainly by the synthesis level of secondary reactive oxygen species. The level of synthesis of superoxide radicals by neutrophils in a state of relative dormancy, increased by 14 days after the operation and is reduced to the reference level to the 21st day. In the preoperative period and before the end of the observation level of synthesis of secondary reactive oxygen species by neutrophils of patients with peritonitis was increased, but is on the background of the slow activation of enzymes, providing a “respiratory burst”. Trend towards normalization of neutrophils chemiluminescent activity in the blood of patients with peritonitis by the end of the observation period (24th day of the postoperative period).Целью исследования явилась оценка клинического состояния и изучение хемилюминесцентной активности нейтрофильных гранулоцитов больных распространенным гнойным перитонитом в динамике послеоперационного лечения. Степень тяжести состояния больных определяли по шкале SAPS, наличие синдрома системной воспалительной реакции – по критериям ACCP/SCCM. Тяжесть и прогноз заболевания оценивали с помощью Мангеймского индекса перитонита и индекса брюшной полости. Наличие и степень выраженности полиорганной недостаточности при поступлении и в динамике послеоперационного периода определяли по шкале SOFA. Исследование люцигенин- и люминол-зависимой хемилюминесценции нейтрофилов при перитоните производили при поступлении в стационар, а также на 7-е, 14-е и 24-е сут послеоперационного периода. У обследованных больных с диагнозом «Распространенный гнойный перитонит 2-й степени тяжести» в 96,2% случаев наблюдались различные системные осложнения (третичный перитонит, перфорации полых органов, абсцессы брюшной полости и др.). Летальность среди обследованных составила 22,2%. При исследовании хемилюминесцентной активности нейтрофильных гранулоцитов установлено, что у больных перитонитом в до- и послеоперационном периодах интенсивность «дыхательного взрыва» определяется преимущественно уровнем синтеза вторичных активных форм кислорода. Уровень синтеза супероксид-радикала нейтрофилами, находящимися в состоянии относительного покоя, повышается только на 14-сут после операции и снижается до контрольных значений к 21-м сут. При индукции «дыхательного взрыва» уровень синтеза супероксид-радикала повышается на 7-е сут послеоперационного периода и остается высоким до конца наблюдения. За весь период наблюдения уровень синтеза вторичных активных форм кислорода нейтрофилами больных перитонитом повышен на фоне замедленной активации ферментов, обеспечивающих «дыхательный взрыв». К концу периода наблюдения (24-е сут послеоперационного периода) выявляется тенденция к нормализации хемилюминесцентной активности нейтрофилов крови больных перитонитом

Study of disturbance wave development in downwards annular flows with a moving frame‐of‐reference brightness‐based laser‐induced fluorescence method

A novel moving frame-of-reference brightness-based laser-induced fluorescence (MFoR-BBLIF) method was developed and demonstrated in downwards co-current air–water annular flows. The method was applied to study the downstream develop- ment of individual disturbance waves in flows over a range of conditions (ReL = 276–1321, ReG = 39,500–79,000). In this method, the optical measurement system, and hence, the region of interrogation (ROI) was translated physically along the length of the test-section with a velocity close to that of individual disturbance waves to obtain the velocities of individual disturbance-waves as a function of downstream distance from the inlet. It was found that the velocities of individual distur- bance waves increase with both downstream distance and gas–liquid flow conditions. In addition, the variation in the wave velocities was more significant at higher gas and liquid Reynolds numbers. The approach can be integrated with many other contactless measurement methods, and can also be used over a range of translation speeds (not necessarily in a “Lagrangian” manner) to study the evolution of important advecting flow phenomena