49 research outputs found
Mechanism of fragmentation and atomization of molecular ions in gasdynamic transport cell
The fragmentation of molecular ions formed upon the electrospraying of a sample and transported through the gasdynamic system of a mass spectrometer equipped with an IESAP (Ion Extraction from Solution at Atmospheric Pressure) source has been experimentally studied. It is established that ion fragmentation in a Kantorowicz-Gray type cell takes place in the immediate vicinity of a skimmer port, apparently, as a result of collisions between ions (accelerated in an electric field) and stagnant gas. Molecular mechanisms of fragmentation are considered and it is concluded that this process can take place in a single ion-molecule collision even
Spectroscopy of Helium Isotope 6He
The excited states of heavy helium isotope 6He were studied in stopped pion absorption in the reactions 9Be
Vertical transport and electroluminescence in InAs/GaSb/InAs structures: GaSb thickness and hydrostatic pressure studies
We have measured the current-voltage (I-V) of type II InAs/GaSb/InAs double
heterojunctions (DHETs) with 'GaAs like' interface bonding and GaSb thickness
between 0-1200 \AA. A negative differential resistance (NDR) is observed for
all DHETs with GaSb thickness 60 \AA below which a dramatic change in the
shape of the I-V and a marked hysteresis is observed. The temperature
dependence of the I-V is found to be very strong below this critical GaSb
thickness. The I-V characteristics of selected DHETs are also presented under
hydrostatic pressures up to 11 kbar. Finally, a mid infra-red
electroluminescence is observed at 1 bar with a threshold at the NDR valley
bias. The band profile calculations presented in the analysis are markedly
different to those given in the literature, and arise due to the positive
charge that it is argued will build up in the GaSb layer under bias. We
conclude that the dominant conduction mechanism in DHETs is most likely to
arise out of an inelastic electron-heavy-hole interaction similar to that
observed in single heterojunctions (SHETs) with 'GaAs like' interface bonding,
and not out of resonant electron-light-hole tunnelling as proposed by Yu et al.
A Zener tunnelling mechanism is shown to contribute to the background current
beyond NDR.Comment: 8 pages 12 fig
Сердечно-легочная реанимация у больных с ожирением
Objective: an analysis of literature covering the effects of morbid obesity on various aspects of cardiopulmonary resuscitation (CPR) and its outcomes. Currently, there is no specific standard for CPR in morbidly obese patients (body mass index ≤ 30). Significant constitutional, anatomical, and physiological factors can lead to negative treatment outcomes in people with significant excess weight. The review presents study results evaluating the effectiveness of the essential components of CPR in obese patients. In particular, it discusses issues of indirect cardiac massage and defibrillation, airway management and ventilation, venous access, and pharmacokinetics of drugs used during CPR. It demonstrates that CPR in obese patients has its own characteristics not mentioned in official recommendations and guidelines.Цель обзора: проанализировать имеющиеся в литературе данные о влиянии ожирения на различные аспекты проведения и исход мероприятий сердечно-легочной реанимации (СЛР). В настоящее время не существует особого стандарта проведения СЛР для пациентов с ожирением (избыточное или патологическое накопление жира с повышением индекса массы тела ≤ 30). Однако наличие у людей с избыточной массой тела значимых конституционально-анатомических и физиологических особенностей может явиться существенным фактором, способным негативно влиять как на ее проведение, так и на результат. Приведены результаты исследований, посвященных оценке эффективности применения наиболее существенных компонентов СЛР у больных с ожирением. Рассмотрены, в частности, вопросы проведения непрямого массажа и дефибрилляции, обеспечения проходимости дыхательных путей и вентиляции, обеспечения венозного доступа, фармакокинетики лекарственных средств, используемых во время СЛР. Показано, что проведение СЛР у пациентов с ожирением имеет свои особенности, которые пока не находят отражения в официальных документах и рекомендациях, но которые необходимо знать
Photoemission study of nano SiC epitaxial layers synthesized by a new method of the atom substitution in Si crystal lattice
Cardiopulmonary resuscitation in obese patients
Objective: an analysis of literature covering the effects of morbid obesity on various aspects of cardiopulmonary resuscitation (CPR) and its outcomes. Currently, there is no specific standard for CPR in morbidly obese patients (body mass index ≤ 30). Significant constitutional, anatomical, and physiological factors can lead to negative treatment outcomes in people with significant excess weight. The review presents study results evaluating the effectiveness of the essential components of CPR in obese patients. In particular, it discusses issues of indirect cardiac massage and defibrillation, airway management and ventilation, venous access, and pharmacokinetics of drugs used during CPR. It demonstrates that CPR in obese patients has its own characteristics not mentioned in official recommendations and guidelines
Spectroscopy of superheavy hydrogen isotopes
The superheavy hydrogen isotopes 4H and 5H have been investigated in the stopped pion absorption on 9Be. Three states of 4H were proposed in the reaction channel 9Be( π{ - }, dt)X. Four states of 5H were proposed in the reaction channels 9Be(π{ - }, pt)X and 9Be(π{ - }, dt)X. The excited states of 5H can decay into free nucleons