Coulomb blockade in metallic grains at large conductance

We study Coulomb blockade effects in the thermodynamic quantities of a weakly disordered metallic grain coupled to a metallic lead by a tunneling contact with a large conductance $g_T$. We consider the case of broken time-reversal symmetry and obtain expressions for both the {\em ensemble averaged} amplitude of the Coulomb blockade oscillations of the thermodynamic potential and the correlator of its {\em mesoscopic fluctuations} for a finite mean level spacing $\delta$ in the grain. We develop a novel method which allows for an exact evaluation of the functional integral arising from disorder averaging. The results and the method are applicable in the temperature range $\delta \ll T \ll E_C$.Comment: 18 pages, 3 figures (revised version

Subcarrier Wave Quantum Key Distribution in Telecommunication Network with Bitrate 800 kbit/s

In the course of work on creating the first quantum communication network in Russia we demonstrated quantum key distribution in metropolitan optical network infrastructure. A single-pass subcarrier wave quantum cryptography scheme was used in the experiments. BB84 protocol with strong reference was chosen for performing key distribution. The registered sifted key rate in an optical cable with 1.5 dB loss was 800 Kbit/s. Signal visibility exceeded 98%, and quantum bit error rate value was 1%. The achieved result is a record for this type of systems

Electrical and light-emitting properties of silicon dioxide co-implanted by carbon and silicon ions

In this paper we explore the electrophysical and electroluminescence (EL) properties of thermally grown 350 nm thick SiO₂ layers co-implanted with Si⁺ and C⁺ ions. The implanting fluencies were chosen in such a way that the peak concentration of excess Si and C of 5-10 at.% were achieved. Effect of hydrogen plasma treatment on electroluminescent and durability of SiO₂ (Si,C) - Si-system is studied. Combined measurements of charge trapping and EL intensity as a function of the injected charge and current have been carried out with the aim of clarifying the mechanisms of electroluminescence. EL was demonstrated to have defect-related nature. Cross sections of both electron traps and hole traps were determined. EL quenching at a great levels of injected charge is associated with strong negative charge capture, following capture of positive charge leading to electrical breakdown of SiO₂ structures

Effects of plasma heating on the magnitude and distribution of plasma flows in the helical divertor of the Uragan-3M torsatron

Recently, a strong up-down asymmetry in the poloidal distributions of diverted plasma flows has been observed in the l = 3/m = 9 Uragan-3M torsatron, in many features similar to what have been observed in the l = 2 Heliotron E heliotron/torsatron. With this asymmetry, the predominant outflow of the diverted plasma is directed with the ion toroidal drift. On this basis, the asymmetry can be related to the space non-uniformity of the charged particle loss. In the work reported, the magnitude of divertor flow in U-3M and the vertical asymmetry in its distribution are studied as functions of the heating parameter P/, P being the power absorbed in the plasma, and are juxtaposed with corresponding P-related changes in the density and fast ion content in the plasma. As P/ increases, an increase of fast ion content and of particle loss, on the one hand, and an increase of divertor flow magnitude and of vertical asymmetry of the flow, on the other hand, are observed. A mutual accordance between these processes validates the hypothesis on a dominating role of fast particle loss in formation of vertical asymmetry of divertor flows in helical devices

Formation of ITB in the vicinity of rational surfaces in the Uragan-3M torsatron

It was shown that there is the possibility of ITB formation in the vicinity of rational surfaces in a torsatron magnetic configuration. The formation of ITB is accompanied by fast change of plasma poloidal rotation velocity, radial electric field and its shear and the decrease of plasma density fluctuations. After the ITB formation the transition to the improved plasma confinement takes place. The transition stars when electron temperature in the region of rational surfaces is sufficient to satisfy the condition υTe/uei>>2πR0 (here υTe is electron thermal velocity and uei is the frequency of ion – electron collisions, and R0 is the major radius of the torus). Such a regime can be maintained during the whole duration of RF discharge without any disturbances.Показано, що існує можливість формування внутрішнього теплового бар’єру (ВТБ) в плазмі ВЧ розряду в околиці раціональних поверхонь в торсатронній магнітній конфігурації. Формування ВТБ супроводжується бистрими змінами швидкості полоідального обертання плазми, радіального електричного поля и його шира і зменшенням флуктуацій густини плазми поблизу раціональних поверхонь. Після формування ВТБ спостерігається перехід в режим поліпшеного утримання плазми. Час переходу зменшується із збільшенням ВЧ потужності нагріву.Показано, что имеется возможность формирования внутреннего теплового барьера (ВТБ) в плазме ВЧ разряда в окрестности рациональных поверхностей в торсатронной магнитной конфигурации. Формирование ВТБ сопровождается быстрыми изменениями скорости полоидального вращения плазмы, радиального электрического поля и его шира и уменьшением флуктуаций плотности плазмы вблизи рациональных поверхностей. После формирования ВТБ наблюдается переход в режим улучшенного удержания плазмы. Время перехода сокращается с увеличением ВЧ мощности нагрева

Energy Liberation in the Flow of Fluid inside the Circular Couette System with Opposed Rotation of Cylinders

The paper presents the design of a heat generator intended for efficient conversion of kinetic wind energy into thermal energy. The design is based on the circulation of the viscous working liquid in the system of cylindrical ring channels, which are formed by the “rotors” rotating opposite (towards) to each other. The results of experiments on measuring the heat capacity of heat generators in different operational modes are presented. The analysis of the obtained results is carried out

Media consumption of different cohorts: TV and Internet

The article considers the dynamics of the TV and Internet consumption of different cohorts under the dramatic changes in the Russian media landscape. In the last decade, the media environment has reached the mass scale in the use of the latest communication technologies based on the high-speed mobile Internet and its various apps. The results of the comparison of the studies of 2012 and 2017 indicate multidirectional trends: an increase in the average daily time of the Internet use in the middle-age and partly elder cohorts, and a moderate increase in the younger groups. The duration of TV viewing is a cyclic phenomenon determined by the stages of life cycle and socialization: the TV consumption of the same cohorts tends to decrease in a five-year interval. According to the theory of media substitution, the Internet is partly a functional alternative to TV for it allows the needs of the audience to be more fully satisfied and to develop on the basis of new technological opportunities. The article also considers features of the media consumption of the digital generation (millennials). This group is internally very different: it consists of several age and social-professional subgroups with serious differences in the average daily TV and Internet consumption. All these trends of the media consumption changed under the covid-19 crisis: changes in the mode of life and a fundamentally different information agenda determined an increase in the media use, primarily TV and the Internet. The long-term trend of the gradual decrease of the TV-audience changed: the average TV viewing increased in all cohorts. Under the crisis, the leading functions of the media - information and recreation - are more in demand than before

Социальные представления о covid-19 в условиях нестабильной информационной среды (исследование середины 2021 года)

The relevance of studying the social consequences of the covid-19 is determined by the fact that this transforming event affected the most diverse aspects of life in the Russian society. The article presents the results of the survey conducted on the sample of the Moscow residents in mid-2021. The majority of respondents considered the coronavirus as a dangerous disease that should be taken seriously. The phenomenon of coronavirus, due to its complexity, poor knowledge and mass distribution, has acquired not only a biomedical, but also a political, economic and media dimension. The information field about the origin, sources and measures to combat this disease experienced changes over time and was often contradictory. A typological analysis showed that there are several groups with different social ideas about the origin, control measures and social consequences of the covid-19. A significant group - about a half of respondents - shared ideas that were alternative to the official and dominant interpretation of the coronavirus in the information field. The study revealed that the agreement on the dangers of the coronavirus was combined with the priority of personal choice of means to combat it. The majority of respondents (61 %) were against the introduction of mandatory vaccination: among the most popular motives were doubts about its effectiveness and fears of its side effects; the priority of individual choice and the rights of citizens rather than the state. A statistically significant relationship was found between attitudes towards mandatory vaccination and trust in government: a low level of agreement with mandatory vaccination obviously correlates with a low level of trust in leading social-political institutions. The authors show that the Russian media discourse on the need for mass vaccination was accompanied by a wide spread of ideas that rigidly differentiate Russian citizens, which cannot but cause concerns about the tasks of ensuring social stability and unity of the Russian society.Актуальность изучения социальных следствий covid-19 определяется тем, что это трансформирующее событие повлияло на самые разные стороны жизни российского общества. В статье приведены результаты опроса о коронавирусной инфекции, проведенного среди жителей столичного мегаполиса в середине 2021 года. Подавляющее большинство респондентов рассматривали коронавирус как опасное заболевание, к которому следует относиться со всей серьезностью. Феномен коронавируса в силу своей сложности, слабой изученности и массовости распространения приобрел не только медико-биологическое, но и политико-экономическое и медийное измерение. Информационное поле о происхождении, источниках и мерах борьбы с заболеванием испытывало изменения во времени и было зачастую противоречивым. Типологический анализ показал, что в обществе существует несколько групп с разными социальными представлениями о происхождении, мерах борьбы и социальных последствиях covid-19. Значительная по численности группа - около половины респондентов - разделяли представления, во многом альтернативные по отношению к официальной и доминирующей в информационном поле интерпретации коронавируса. Исследование показало, что широкое согласие с опасностью коронавируса сочеталось с приоритетом личного выбора средств борьбы с ним. Большинство опрошенных (61 %) было против введения обязательной вакцинации: среди наиболее популярных мотивов - сомнения в ее эффективности и опасения побочных эффектов; приоритет индивидуального выбора и прав граждан, нежели государства. Была обнаружена статистически значимая связь между отношением к обязательной вакцинации и доверием к власти: невысокий уровень согласия с обязательной вакцинацией очевидным образом соотносится с низким уровнем доверия к ведущим социально-политическим институтам. Показано, что российский медийный дискурс о необходимости массовой вакцинации сопровождался широким распространением построений, жестко дифференцирующих российских граждан, что не может не вызывать озабоченности в связи с задачами обеспечения социальной стабильности и единства общества

Unprecedented Coordination-Induced Bright Red Emission from Group 12 Metal-Bound Triarylazoimidazoles

Arylazoimidazoles are important dyes which were intensively studied in the past. In contrast, triarylazoimidazoles (derivatives which carry aryl substituents at the imidazole core) received almost no attention in the scientific literature. Here, we report a new family of simple and easily accessible triarylazoimidazole-group 12 metal complexes, which feature highly efficient photo-luminescence emission (Φ up to  0.44). Novel compounds exhibit bright red emission in solution, which could be excited with a visible light