Calibrating the {\alpha} parameter of convective efficiency using observed stellar properties

Context. Synthetic model atmosphere calculations are still the most commonly used tool when determining precise stellar parameters and stellar chemical compositions. Besides three-dimensional models that consistently solve for hydrodynamic processes, one-dimensional models that use an approximation for convective energy transport play the major role. Aims. We use modern Balmer-line formation theory as well as spectral energy distribution (SED) measurements for the Sun and Procyon to calibrate the model parameter {\alpha} that describes the efficiency of convection in our 1D models. Convection was calibrated over a significant range in parameter space, reaching from F-K along the main sequence and sampling the turnoff and giant branch over a wide range of metallicities. This calibration was compared to theoretical evaluations and allowed an accurate modeling of stellar atmospheres. Methods. We used Balmer-line fitting and SED fits to determine the convective efficiency parameter {\alpha}. Both methods are sensitive to the structure and temperature stratification of the deeper photosphere. Results. While SED fits do not allow a precise determination of the convective parameter for the Sun and Procyon, they both favor values significantly higher than 1.0. Balmer-line fitting, which we find to be more sensitive, suggests that the convective efficiency parameter {\alpha} is $\approx$ 2.0 for the main sequence and quickly decreases to $\approx$ 1.0 for evolved stars. These results are highly consistent with predictions from 3D models. While the values on the main sequence fit predictions very well, measurements suggest that the decrease of convective efficiency as stars evolve to the giant branch is more dramatic than predicted by models.Comment: 14 pages, 16 figures, accepted for publication in A&

Terahertz Bloch oscillator with a modulated bias

Electrons performing Bloch oscillations in an energy band of a dc-biased superlattice in the presence of weak dissipation can potentially generate THz fields at room temperature. The realization of such Bloch oscillator is a long-standing problem due to the instability of a homogeneous electric field in conditions of negative differential conductivity. We establish the theoretical feasibility of stable THz gain in a long superlattice device in which the bias is quasistatically modulated by microwave fields. The modulation waveforms must have at least two harmonics in their spectra.Comment: 5 page

Prediction of physical-chemical and fire hazard characteristics by carbon chain rules. 2. Carboxylic acids

Investigation of the dependence of physico-chemical and fire hazard properties from the chemical structure of carboxylic acids is carried out. Forecasting of the boiling temperature, the flash point, the temperature and the concentration flammability limits, the heats of combustion and vaporization is performed by the carbon chain rules (CCR). The following empirical equations for the calculation of physico-chemical and fire hazard indices from the conventional carbon chain and from the number of carbon atoms are proposed for the convenience of practical application of the CCR. A comparative analysis of the proposed methods for the flash point calculating and the already known methods of GOST 12.1.044-89, Mendeleev and ACD/Lab 2014 is carried out. It is shown, basically, that the new methods give more accurate calculation results than the comparison design procedures. © Siberian Federal University. All rights reserve

THE NATURE OF CONNECTION BETWEEN CHILD’S ATTACHMENT TO THE MOTHER AND THE EXPERIENCE OF FAMILY WELL-BEING IN ADULTHOOD

Подано дослідження характеру зв’язку типу дитячої прив’язаності до матері із задоволеністю життям у дорослому віці. Прив’язаність до матері розглянуто як найперший зразок відносин із близькою людиною, тому її якість впливає на відносини з партнером. Доведено, що тип прив’язаності до матері в дитинстві визначає можливість проявів уникнення близькості з партнером, тривожності з приводу втрати цієї близькості, а також особливості спілкування та рольових очікувань і домагань у подружжі.Для изучения связи типа детской привязанности к матери с переживанием взрослым человеком благополучия в собственной семье было обследовано 78 респондентов. Выявлены: тип привязанности к матери у взрослого человека (авторская анкета), ролевые ожидания и притязания в браке (опросник «Ролевые ожидания и притязания в браке»        А.Н. Волковой), степень удовлетворенности браком       («Тест-опросник удовлетворенности браком» В.В. Столина, Т.Л. Романовой, Г.П.  Бутенко),  особенности  близких  отношений  (опросник  «Опыт  близких  отношений»           К.  Бреннана  и  Р.К.  Фрейли  в  адаптации                          Т.В. Казанцевой;  особенности общения  в  семье  (методика  «Общение  в  семье»  (Ю.Е.  Алешиной,  Л.Я.  Гозмана, Е.М. Дубовской). Обработка данных была произведена с применением F-критерия Фишера и коэффициента корреляции Пирсона. Получены следующие результаты: тип привязанности к матери в детстве связан с проявлениями близости к партнеру,  тревожности  по  поводу  потери  близких  отношений,  особенностями  общения, ролевыми ожиданиями и притязаниями в браке.Background. Attachment to mother is viewed as the primary sample of bonding with a close person, thus its quality has an impact on the relationships with a partner.Objectives. A research of the nature of connection between child’s attachment to mother and the experience of the family well-being in adulthood is presented.Method. The empirical research was carried out by internet survey with the help of the following methods: “Satisfaction with marriage” by Stolin V., Butenko G., Romanova T.; “Experience of close relationship” by Brennan K. and Freiley P. adapted by Kazantseva T.; “Role expectations and claims in marriage” by Volkova A.; “Communication in the family” by Alyoshina Yu., Gozman L., Dubovski M.; and the author’s survey revealing the type of child’s attachment to mother in adulthood.Fisher criterion F was used for the comparison of different samples; Pearson’s correlation coef?cient was used for the determination of correlation between the type of attachment to mother and components of psychological well-being.Sample. In the course of the research 39 couples living in registered marriage were surveyed, which constitutes 78 respondents aged 23-42.Results. The type of attachment to mother in person’s childhood determines the possibility of displaying avoidance of closeness to the partner, anxiety caused by the loss of closeness as well as peculiarities of communication, role expectations and claims in a couple.Conclusions. People with an indifferent type of attachment often avoid intimacy with a partner, perform well in the sphere of emotional and psychological support of a partner and even exhibit a higher degree of mutual understanding with the partner. People with neurotic type of attachment may experience anxiety about the loss of intimacy with a partner, but this anxiety can make them constantly work on themselves, both in physical terms – with an external attachment or on a psychological level – for the presence of con?dence and safety