Main results of atmospheric fine structure parameter observation in the lower thermosphere

The capabilities of the radiometeor method of wind measurement increase with the increase of the transmitted power of radar stations fitted with goniometric systems which enables the observation of shower meteors along with sporadic background. In shower observations the meteor zone reflecting area narrows to the echo surface which is perpendicular to the flux radiant. Favorable conditions are created for singling out atmospheric disturbances in which the wave front is parallel to the echo surface which plays, in this case, the role of a frequency filter. For the first time this technique allowed wave disturbances with periods of approx. greater than 4 min. to be measured, with about a 99 percent probability of exceeding the level of the turbulence noise, during the Geminid and Perseid showers. Maximum values of such wave disturbance amplitudes were about 15 to 20 m/s, with lifetimes up to 2 hrs

Exact Results for Spectra of Overdamped Brownian Motion in Fixed and Randomly Switching Potentials

The exact formulae for spectra of equilibrium diffusion in a fixed bistable piecewise linear potential and in a randomly flipping monostable potential are derived. Our results are valid for arbitrary intensity of driving white Gaussian noise and arbitrary parameters of potential profiles. We find: (i) an exponentially rapid narrowing of the spectrum with increasing height of the potential barrier, for fixed bistable potential; (ii) a nonlinear phenomenon, which manifests in the narrowing of the spectrum with increasing mean rate of flippings, and (iii) a nonmonotonic behaviour of the spectrum at zero frequency, as a function of the mean rate of switchings, for randomly switching potential. The last feature is a new characterization of resonant activation phenomenon.Comment: in press in Acta Physica Polonica, vol. 35 (4), 200

Political Selfconsciousness of Captured White General Staff Officers Based on the Materials of Soviet Questionnaires of the Early 1920s

Submitted: 18.09.2022. Accepted: 18.01.2024.Поступила в редакцию: 18.09.2022. Принята к печати: 18.01.2024.На основе советских анкет пленных белых генштабистов начала 1920-х гг., хранящихся в фондах Российского государственного военного архива, рассматривается проблема политической самоидентификации «бывших» в красном плену. Анкетирование бывших белых производилось в целях их учета. Особое значение для оценки взглядов пленных имели разделы анкет об их отношении к событиям Февральской и Октябрьской революции, а также об их актуальных убеждениях. Анализ анкет как массового исторического источника позволяет составить представление об общественно-политической позиции группы пленных белых генштабистов в целом. По большинству вопросов взгляды пленных сходились. Как правило, они принимали Февральскую революцию и не принимали Октябрьскую. Резко критические отзывы звучали о старом режиме. Чрезвычайно интересны объяснения причин неприятия захвата власти большевиками. Для многих приемлемым ответом было указание на непонимание задач новой революции. В то же время некоторые указывали реальные причины такого неприятия — красный террор, развал старой армии, тяжелый Брестский мир. Обращают на себя внимания те стратегии, которые использовали составители анкет при ответах на острые и потенциально опасные вопросы. Нередко в качестве ответов указывалось, что революция носила народный характер, а автор анкеты стремился служить народу или приветствовал народовластие и был солидарен с политикой РКП(б). Отдельные авторы, не желая излагать свои подлинные взгляды, декларативно заявляли о необходимости честно трудиться на благо общества. «Бывшие» старались давать ответы, которые бы понравились новому начальству и контролирующим органам, что позволило бы бывшим белым скорее интегрироваться в командный состав Красной армии и снять с себя дискриминационный статус бывших белых офицеров, состоявших на особом учете.Based on Soviet questionnaires of captured White General Staff officers of the early 1920s kept in the funds of the Russian State Military Archive, this article considers the problem of political self-identification of the “former” officers in Red captivity. The survey of former Whites was carried out to account for them. Sections of questionnaires about the prisoners’ attitude to the events of the February and October Revolutions, as well as about their current beliefs were of particular importance for assessing their views. The analysis of questionnaires as a mass historical source makes it possible to get an idea of the sociopolitical position of the group of captured White General Staff officers. On most issues, the prisoners’ views converged. As a rule, they accepted the February Revolution and did not accept the October Revolution. Also, they were highly critical of the old regime. Explanations of the reasons for the rejection of the seizure of power by the Bolsheviks are of considerable interest. For many, an acceptable answer was an indication of a lack of understanding of the tasks of the new revolution. At the same time, some pointed out the real reasons for such rejection, i.e. the Red Terror, the collapse of the old army, and the hard Brest peace treaty. The strategies used by the questionnaire compilers in answering acute and potentially dangerous questions draw the researchers’ attention. Often, the answers indicated that the revolution was of a popular nature, and the author of the questionnaire sought to serve the people or welcomed the rule of the people and was in solidarity with the policy of the RCP(b). Some authors, not wanting to express their true views, declared the need to work honestly for the benefit of society. The “former” tried to give answers that would appeal to the new superiors and regulatory authorities, which would allow them to integrate into the command structure of the Red Army more quickly and remove from themselves the discriminatory status of former White officers who were on special registry

Wind regime of the mesosphere - Lower thermosphere of the Earth

Nowadays investigations of the wind regime of the mesosphere - lower thermosphere (80-100 km) using ground-based (including radiometeor method) and satellite measurements allow the setting and the decision of the task of the creation the global model of the circulation including background motions and temporal variability. The temporal variability is due to the wide spectrum of temporal and spatial scales of waves existing in the atmosphere. Radiosystem of Kazan University is one of 23 meteor radars operating currently in the World. Radiometeor wind measurements in Kazan University started in 1964. During the period of 1964-1965, the first annual cycle of observation is accomplished. Long cycles of observations accomplished during 1979-2002. Uninterrupted cycle of observations started in November 2002 allowed the detailed structure of the temporal variability in the region of the mesosphere - lower thermosphere. Modern methods of the analysis along with background motions allowed the detection of short-period (5-10 minutes) innergravity waves, tidal waves, planetary waves (2-30 days), seasonal variations (annual and semiannual oscillations). Dynamics of this height region of the atmosphere presents significant scientific and practical interests. Due to propagating from the lower atmosphere waves experience the dissipation and the filtration and affects to the altitudinal and seasonal structure of the circulation we should expect the affection of these waves to the disturbed structure of the ionosphere

2,4-Dithiouracil: the reproducible H-bonded structural motifs in the complexes with 18-membered crown ethers

[[abstract]]2,4-Dithiouracil (DTU) forms in the crystals the H-bonded monohydrates of a 1 : 1 : 1 ratio with 18-crown-6 (18C6) 1, cis,syn,cis-isomer of dicyclohexano-18-crown-6 (DCH6A) 2, and benzo-18-crown-6 (B18C6) 3, while the anhydrous adduct with cis,anti,cis-isomer of dicyclohexano-18-crown-6 (DCH6B) 4 is of a 2 : 1 ratio. In 1–3 the components reproducibly alternate in the chains, while in 4 the chains are built of the alternative centrosymmetric dimers of 2,4-dithiouracil and the molecules of the cis,anti,cis-isomer of dicyclohexano-18-crown-6.[[journaltype]]國外[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子版[[countrycodes]]GB

Nitrides as ammonia synthesis catalysts and as potential nitrogen transfer reagents

In this article, an overview of the application of selected metal nitrides as ammonia synthesis catalysts is presented. The potential development of some systems into nitrogen transfer reagents is also described

Resilience management during large-scale epidemic outbreaks

Assessing and managing the impact of large-scale epidemics considering only the individual risk and severity of the disease is exceedingly difficult and could be extremely expensive. Economic consequences, infrastructure and service disruption, as well as the recovery speed, are just a few of the many dimensions along which to quantify the effect of an epidemic on society's fabric. Here, we extend the concept of resilience to characterize epidemics in structured populations, by defining the system-wide critical functionality that combines an individual’s risk of getting the disease (disease attack rate) and the disruption to the system’s functionality (human mobility deterioration). By studying both conceptual and data-driven models, we show that the integrated consideration of individual risks and societal disruptions under resilience assessment framework provides an insightful picture of how an epidemic might impact society. In particular, containment interventions intended for a straightforward reduction of the risk may have net negative impact on the system by slowing down the recovery of basic societal functions. The presented study operationalizes the resilience framework, providing a more nuanced and comprehensive approach for optimizing containment schemes and mitigation policies in the case of epidemic outbreaks

Redox-controlled potassium intercalation into two polyaromatic hydrocarbon solids

Alkali metal intercalation into polyaromatic hydrocarbons (PAHs) has been studied intensely after reports of superconductivity in a number of potassium- and rubidium-intercalated materials. There are, however, no reported crystal structures to inform our understanding of the chemistry and physics because of the complex reactivity of PAHs with strong reducing agents at high temperature. Here we present the synthesis of crystalline K2Pentacene and K2Picene by a solid–solid insertion protocol that uses potassium hydride as a redox-controlled reducing agent to access the PAH dianions, and so enables the determination of their crystal structures. In both cases, the inserted cations expand the parent herringbone packings by reorienting the molecular anions to create multiple potassium sites within initially dense molecular layers, and thus interact with the PAH anion π systems. The synthetic and crystal chemistry of alkali metal intercalation into PAHs differs from that into fullerenes and graphite, in which the cation sites are pre-defined by the host structure

Room temperature antiferromagnetic order in superconducting X_yFe_{2-x}Se_ 2, (X= Rb, K): a powder neutron diffraction study

Magnetic and crystal structures of superconducting X yFe 2-xSe 2 (X= Rb and K with Tc=31.5 K and 29.5 K) have been studied by neutron powder diffraction at room temperature. Both crystals show ordered iron vacancy pattern and the crystal structure is well described in the I4/m space group with the lattice constants a=8.799, c=14.576 and a=8.730, c=14.115 A, and the refined stoichiometry x=0.30(1), y=0.83(2) and x=0.34(1), y=0.83(1) for Rb- and K-crystals respectively. The structure contains one fully occupied iron position and one almost empty vacancy position. Assuming that the iron moment is ordered only on the fully occupied site we have sorted out all eight irreducible representations (irreps) for the propagation vector k=0 and have found that irreps tau_2 and tau_7 well fit the experimental data with the moments along c-axis. The moment amplitudes amounted to 2.15(3) mu_B, 2.55(3) mu_B for tau_2 and 2.08(6) mu_B, 2.57(3) mu_B for tau_7 for Rb- and K-crystals respectively. Irrep tau_2 corresponds to the Shubnikov group I4/m' and gives a constant moment antiferromagnetic configuration, whereas tau_7 does not have Shubnikov counterpart and allows two different magnetic moments in the structure.Comment: 5 pages, 1 table, 4 figure

Cooling quasiparticles in A(3)C(60) fullerides by excitonic mid-infrared absorption

Long after its discovery, superconductivity in alkali fullerides A(3)C(60) still challenges conventional wisdom. The freshest inroad in such ever-surprising physics is the behaviour under intense infrared excitation. Signatures attributable to a transient superconducting state extending up to temperatures ten times higher than the equilibrium T-c similar to 20 K have been discovered in K3C60 after ultra-short pulsed infrared irradiation-an effect which still appears as remarkable as mysterious. Motivated by the observation that the phenomenon is observed in a broad pumping frequency range that coincides with the mid-infrared electronic absorption peak still of unclear origin, rather than to transverse optical phonons as has been proposed, we advance here a radically new mechanism. First, we argue that this broad absorption peak represents a 'super-exciton' involving the promotion of one electron from the t(1u) half-filled state to a higher-energy empty t(1g) state, dramatically lowered in energy by the large dipole-dipole interaction acting in conjunction with the Jahn-Teller effect within the enormously degenerate manifold of (t(1u))(2)(t(1g))(1) states. Both long-lived and entropy-rich because they are triplets, the infrared-induced excitons act as a sort of cooling mechanism that permits transient superconductive signals to persist up to much higher temperatures