bluuebunny/crossref_metadata_2025 huggingface dataset:
The Changing Seismic Site Response of the Brienz/Brinzauls Rock Slope Instability: Insights from 5 Years of Monitoring Before, During and After a Partial Collapse in June 2023
Authors: Häusler Mauro , Glueer Franziska , Fäh Donat
Published: December 2024

Unstable rock slopes pose significant hazards, requiring reliable monitoring for effective mitigation. However, existing methods often struggle to capture the dynamic nature of these environments, highlighting the need for enhanced monitoring techniques. This study investigates the Brienz/Brinzauls landslide in Switzerland to deepen our understanding through passive seismic techniques. The objective is to gain insights into the evolving seismic response of active slopes before, during and after collapse events, thus, filling gaps in our understanding of the dynamics of the seismic response of landslides. We deployed automated tracking of seismic parameters spanning 5 years (2018–2023) and covering a partial collapse of the landslide, and tracked resonance frequencies, seismic amplitudes, wavefield polarization, and seismic event occurrences. In addition, we compared the seismic parameters with geodetic surface displacement rates. Over the 5 years, significant seismic parameter shifts were observed associated with increased rock fall events, resonance frequency reductions, and changes in wavefield polarization. Immediate seismic responses during and post-collapse in June 2023 gradually reverted to pre-event conditions within 2 weeks. This study provides new data-driven insights into unstable rock slope behavior, potentially contributing to the development of new ways of seismic early-warning systems. It emphasizes the necessity of ongoing and future monitoring efforts to accurately anticipate future landslide incidents, given the degree of uncertainties in the parameters monitored, for example, caused by transient seismic signals.
Landslides of Moscow River Valley (Russia): Types and Features of their Origin in Different Geological Conditions
Authors: Novikov Pavel V. , Zerkal Oleg V. , Barykina Olga S. , Samarin Eugene N.
Published: December 2024

The Moscow River valley is an actively developed area in Russia within the Moscow agglomeration, where landslide processes are widely developed. There are four main types of landslides here. The greatest hazard for economic activity is large rotational slides. Such landslides differ in size, features of displacement zones and sediments involved in displacement. It was found that landslide massifs formed in different geological conditions have significant differences in internal structure and present-day activity. A detailed study of landslide processes in several areas of the Moscow River valley and its tributaries revealed key features of changes in the internal structure and properties of the main deformable horizons during the development of landslide processes.
Diskussion der Arbeit
Authors: Abels Nele
Published: December 2024

In diesem Kapitel werden die Ergebnisse der Arbeit in Hinblick auf die Forschungsfragen diskutiert, also zu den Bereichen Argumentation (und Beweise) sowie Metakognition. Zudem werden weiterreichende Erkenntnisse dargestellt und erklärt sowie mögliche Einschränkungen der Untersuchung betrachtet.
Datenaufbereitung
Authors: Abels Nele
Published: December 2024

In diesem Kapitel wird die Datenaufbereitung erläutert, wobei Videos (Abschnitt 7.1), Transkripte (Abschnitt 7.2) und Referenzskizzen betrachtet werden (Abschnitt 7.3).
The Roma and their Musical Translations—Between Adaptation and Interpretation
Authors: Piotrowska Anna G.
Published: December 2024

Dieses Kapitel fokussiert auf Übersetzung im Kontext der Strategien – oft subversiver Natur –, die von Roma angewandt werden, insbesondere, aber nicht ausschließlich, in Bezug auf ihre musikalischen Praktiken. Der Begriff „musikalische Übersetzung“ kann auf vielfältige Weise verstanden werden, daher beginnt das Kapitel mit einer Definition, die sich hauptsächlich auf die übersetzerischen Praktiken der Roma und die Rezeption der Roma als Musiker und Entertainer bezieht. Seit dem Mittelalter sind Roma-Musiker Multiplikatoren, möglicherweise Mitautoren und Herausgeber und, wie in diesem Kapitel dargelegt wird, auch Übersetzer musikalischer Ideen.
Probabilistic seismic hazard assessment associated with induced seismicity at geothermal sites in the Upper Rhine Graben (Southern Germany)
Authors: Azari Sisi Aida , Hobiger Manuel , Spies Thomas , Steinberg Andreas
Published: December 2024

The extraction of geothermal energy is associated with induced seismicity. Depending on the extraction parameters, such as injection pressure and volume, the induced seismicity is time-dependent. We investigate the case of the two geothermal power plants of Insheim and Landau, which are located in the Upper Rhine Graben in Southwest Germany. The induced seismicity was observed by a local seismic network consisting of a total of 19 stations, resulting in an earthquake catalog comprising 930 events for the Landau reservoir and 1985 events for the Insheim reservoir, both between 2012 and 2022. Based on this earthquake catalog, seismic source areas are defined for both reservoirs, and a probabilistic seismic hazard assessment (PSHA) is performed. Using temporal subsets of the earthquake catalog, PSHA can also be performed for shorter time ranges, resulting in larger expected PGV values in times of higher induced seismicity. The seismic velocity profiles obtained by site effect studies based on ambient seismic noise measurements highlight relatively large variations of the site effects on short scales in the area. The consequences of these lateral variations on the seismic hazard assessment are also discussed.
Constitution-Building After the Arab Spring
Authors: Biagi Francesco
Published: December 2024

How were post-Arab Spring constitutions drafted? What are the most significant elements of continuity and change within the new constitutional texts? What purposes are these texts designed to serve? To what extent have constitutional provisions been enforced? Have the principles of constitutionalism been strengthened compared to the past? These are some of the key questions Francesco Biagi addresses. Constitution Building After the Arab Spring. A Comparative Perspective examines seven national experiences of constitution building in the Arab world following the 2011 uprisings, namely those of Morocco, Algeria, Tunisia, Libya, Egypt, Syria, and Jordan. This interdisciplinary book, based largely on the author's own work and research in the region, compares these seven national experiences through four analytical frameworks: constitution-drafting and constitutional reform processes; separation of powers and forms of government; constitutional justice; and religion, women and non-Muslims within the framework of citizenship.
CATEGORICAL FOUNDATIONS OF FORMALIZED CONDENSED MATHEMATICS
Authors: ASGEIRSSON DAGUR , BRASCA RICCARDO , KUHN NIKOLAS , NUCCIO MORTARINO MAJNO DI CAPRIGLIO FILIPPO ALBERTO EDOARDO , TOPAZ ADAM
Published: December 2024

Condensed mathematics, developed by Clausen and Scholze over the last few years, proposes a generalization of topology with better categorical properties. It replaces the concept of a topological space by that of a condensed set, which can be defined as a sheaf for the coherent topology on a certain category of compact Hausdorff spaces. In this case, the sheaf condition has a fairly simple explicit description, which arises from studying the relationship between the coherent, regular, and extensive topologies. In this paper, we establish this relationship under minimal assumptions on the category, going beyond the case of compact Hausdorff spaces. Along the way, we also provide a characterization of sheaves and covering sieves for these categories. All results in this paper have been fully formalized in the Lean proof assistant.
Argumentum ad Lunam: Pauline Discourse, “Double Death,” and Competition on the Moon
Authors: Walsh Robyn Faith
Published: December 2024

This article asks what Paul’s claims about cosmology signify in terms of his competitive position on the nature and purpose of the moon. Specifically, in an age in which discourses and demonstrations involving the moon were rife, I argue that Paul is invoking principals shared by writers like Plutarch on the “double death” of the human being (first as soma on the earth, then as psyche/nous in orbit around and on the moon) and that he envisions an afterlife among the stars in pneumatic form that, to the degree it is anthropomorphic, is ideally male. I also posit that this aspect of Paul’s thought has been overlooked, in part due to the idiosyncratic-yet-pervasive translation of doxa in Paul as “glory” rather than in terms related to typologies and judgment, as it is elsewhere in Greek philosophical literature.
“… angels which Thou hast created of snow and of fire”: Bahá’í Angelology and God’s Dialogic Relationship to Humanity
Authors: Hughey Matthew W.
Published: December 2024

Angelology is in a renaissance. Yet the angels of new religious movements in general, and the Bahá’í Faith in particular, remain less examined. In response, I offer a typology of Bahá’í angels as avatars of the Holy Spirit, distinct celestial beings, spiritually evolved people, manifestations of God, and carriers and personifications of divine virtue. These five types respectively function to emphasize the authority of divinity, accentuate the mystery of spiritual reality, reconcile spirituality and materialism through the duality of human nature, position prophets as “manifestations” of God in the context of “progressive revelation,” and attempt to make the unknowable God knowable through the transformation of axiology to ontology. Collectively, Bahá’í angels illumine an understanding of religion as a dialogic relationship. Religion is reconceived as an interactional balance of divine will and human agential choice.
Refractions of Katyn: Photography and Witnessing in Soviet Investigations of Mass Atrocities
Authors: Chan Paula
Published: December 2024

The Soviet Extraordinary State Commission (Chrezvychainaia gosudarstvennaia komissiia, ChGK) was founded on November 2, 1942. From the outset, photography and eyewitnesses were vital resources for conveying the horrors of the German occupation. Refuting accusations that the USSR was responsible for massacring Polish prisoners of war in Katyn forest further magnified the importance of generating an irrefutable record of Nazi guilt. This article examines the efforts of Stalin's government to bury the Katyn lie beneath images of genuine victims of Hitler's regime. Tracing the diverse origins of the ChGK's photographs and supporting testimony brings into focus the reasons why wartime observers found the Soviet falsification convincing. ChGK materials should be approached as artifacts of mass mobilization. By disentangling these pictures and pages from their propagandistic uses, researchers can move closer to understanding the symbiotic relationship between official narratives and personal truths in the USSR as well as the post-Soviet Russian Federation.
A Review of Suspended Sediment Hysteresis
Authors: Jing Tongge , Zeng Yi , Fang Nufang , Dai Wei , Shi Zhihua
Published: December 2024

The study of sediment‐riverflow interactions during discrete hydrological events is vital for enhancing our understanding of the hydrological cycle. Hysteresis analysis, relying on high‐resolution, continuous monitoring of suspended sediment concentration (SSC) and discharge (Q) data, is an effective tool for investigating complex hydrological events. It captures differing sediment dynamic at the same discharge level, which results from the asynchrony between the hydrograph and sediment graph during different phases of the event. However, there has been no comprehensive review systematically addressing the utility and significance of hysteresis analysis in soil and water management. This review synthesizes findings from over 500 global studies, providing a detailed examination of current research. We trace the development and application of hysteresis analysis in hydrology, illustrating its role in classifying and characterizing events, as well as uncovering sediment sources and transport mechanisms. Furthermore, hysteresis analysis has proven effective in identifying critical hydrological events, offering valuable insights for targeted watershed management. Our spatiotemporal analysis of global hysteresis research shows that over 70% of studies are located in semi‐arid and Mediterranean climate zones, with an increasing focus on alpine and tropical regions due to climate change. This review also highlights critical limitations, including the scarcity of high‐resolution data, inconsistent use of quantitative indices, and limited integration of hysteresis patterns into predictive hydrological approaches. Future research should focus on developing region‐specific hydrological models that incorporate hysteresis dynamics, along with standardizing methodologies to apply hysteresis analysis across diverse climatic and geomorphic settings.
AutoML based workflow for design of experiments (DOE) selection and benchmarking data acquisition strategies with simulation models
Authors: Xu Xukuan , Li Donghui , Bi Jinghou , Moeckel Michael
Published: December 2024

Design of experiments (DOE) is an established method to allocate resources for efficient parameter space exploration. Model based active learning (AL) data sampling strategies have shown potential for further optimization. This paper introduces a workflow for conducting DOE comparative studies using automated machine learning. Based on a practical definition of model complexity in the context of machine learning, the interplay of systematic data generation and model performance is examined considering various sources of uncertainty: this includes uncertainties caused by stochastic sampling strategies, imprecise data, suboptimal modeling, and model evaluation. Results obtained from electrical circuit models with varying complexity show that not all AL sampling strategies outperform conventional DOE strategies, depending on the available data volume, the complexity of the dataset, and data uncertainties. Trade-offs in resource allocation strategies, in particular between identical replication of data points for statistical noise reduction and broad sampling for maximum parameter space exploration, and their impact on subsequent machine learning analysis are systematically investigated. Results indicate that replication oriented strategies should not be dismissed but may prove advantageous for cases with non-negligible noise impact and intermediate resource availability. The provided workflow can be used to simulate practical experimental conditions for DOE testing and DOE selection.
Improving small-scale cultivation of Spodoptera frugiperda 9 cells by silanizing glassware
Authors: Worch Kristina , Mühlnickel Benjamin Ole , Pieper Jana , Burse Antje
Published: December 2024

Cultivating insect cells in glass vessels can be challenging. Due to uncontrolled cell adhesion and associated cell loss as well as clumping, the replication of experiments is put at risk. A cost-effective solution to improve and stabilize cultivation may be to silanize glass vessels, making them more hydrophobic and chemically inert. Therefore, the cell growth parameters of Spodoptera frugiperda (Sf) 9 cells were characterized in an experiment comparing silanized and non-silanized vessels of three different sizes. Silanization had a significantly positive effect on living cell count and viability in small-scale cultivation (10 ml culture tubes and 50 ml culture flasks) by reducing adhesion of cells to the vessel walls. The treatment also improved the comparability of the biological replicates by reducing the variance of measurements. No such effects could be observed for larger 250 ml culture flasks. Overall, the results indicate that silanization can improve cultivation, especially when working with small glass vessels.
Detection of Lip, Tongue, Masseter, and Temporalis Muscle Contractions with Electromyography Tools as an Early Diagnostic Medium for Dentoalveolar Malocclusion
Authors: Achmad Harun , Areni Intan Sari , Sumintarti Sumintarti , Ramadhany Sri , Ardiansya Reza , Edy Sarwo , Kuandinata Wesley
Published: December 2024

Objectives This study aims to detect early class I, II, and III malocclusions through the muscle strength of the lips, tongue, masseter, and temporalis.

Materials and Methods The study subjects were 30 pediatric patients with predetermined criteria. The subjects were divided into class I, II, and III malocclusions where each classification of malocclusion amounted to 10 people. Subjects were differentiated according to gender and age. Tongue pressure during swallowing was recorded by a palatal measurement sensor system. The strength of the activity was assessed when the lip muscles resisted as hard as possible the traction plate placed between the teeth and the lips, then the force was connected to an electromyograph (EMG) to be measured. Temporal and masseter muscle contractions were assessed when the muscles performed swallowing, chewing, mouth opening, resting, mouth closing, and biting movements.

Statistical Analysis Data analysis using the SPSS application was performed with the ANOVA test if the data distribution was normal, and if the data distribution was not normal, then the Kruskal–Wallis test was used. Significant data were evaluated by post-hoc tests using least significant difference if the data distribution was normal or the Mann–Whitney test if the data distribution was not normal.

Results It was found that there was a significant difference in the left masseter muscle and left temporalis muscle.

Conclusion EMG can be considered as a tool to detect class I, II, and III malocclusions through muscle contraction. Biting and chewing positions have satisfactory EMG examination results for malocclusion detection. Age and gender of the child may affect the results of EMG examination in certain conditions.
Reparative justice and the victim’s burden: why accepting an apology is not a moral obligation
Authors: Hay Colin
Published: December 2024

A number of authors make a seemingly compelling case for holding the victim of a wrong morally obliged to accept the genuine apology of the wrongdoer. This is a crucial issue in questions of reparative justice, since reparation typically requires not just the giving but also the acceptance of an apology. Yet it is a case that we should ultimately reject. If it is credible to think that the victim might suffer anew in exercising any duty of this kind, that suffering must be factored into the moral reckoning from the outset. It is only if we can be sure that the victim will not suffer again by attending to, and ultimately accepting, the wrongdoer’s apology that it would be right to impose upon her any duty of this kind. Yet, in all non-trivial cases, the victim’s burden is unknowable in advance and has the potential to be considerable. In such situations, I argue, the victim has no duty to accept the wrongdoer’s apology. There are limits, too, to the utility of the bipartite victim-wrongdoer account of reparation on which such arguments are typically predicated. For the harm the wrongdoer causes is not exclusively suffered by the immediate victim but also by the community of all potential victims. Genuine reparative justice requires more than a recalibration of the relative moral standing of the wrongdoer and the victim through the giving and receiving of an apology. I consider how this might be achieved without imposing upon the victim a burden that fails to achieve the moral reckoning anticipated.
Surface excitations in a nonideal Bose gas and surface tension of helium II
Authors: Pikhitsa P. V.
Published: December 2024

Gapless surface excitations in a nonideal Bose gas are investigated. It is shown that besides a capillary wave, two branches of excitations of the phonon type (i.e., surface phonons) exist on the surface of the Bose gas. Together with the capillary mode, these surface phonons fully determine the temperature dependence of the surface tension of helium II at low temperatures.
Asymmetry of the thermal kink response to a current step in homogeneous superconductors
Authors: Bezuglyi A. I. , Shklovskii V. A.
Published: December 2024

The transient process in which the velocity of the thermal kink that arises as a result of a current step attains a new value is considered theoretically. It is shown that when a “fast” kink (|v0| ≫ 1) moves toward the region of the N-phase, the duration of this transient process is v02/4 times longer than in the case of motion toward the region of the S-phase (v0 is the initial kink velocity). The physical meaning of this result is clarified.
Phase transitions in systems with local triplet pairs
Authors: Beloborod’ko S. I. , Pedan A. G. , Kulik I. O.
Published: December 2024

We have studied transitions to the superconducting and charge-density wave (CDW) states as well as antiferromagnetic transitions in systems containing local triplet pairs. In a self-consistent field approximation we calculate the corresponding transition temperatures. It is shown that application of a magnetic field leads to a splitting of the transition to the superconducting state. We consider the possibility of the existence of several phases. We obtain the temperature for the transition to a mixed antiferromagnetic-CDW state. The entire phase diagram of the system is constructed.
Quantum fluctuations in superconducting point contacts
Authors: Khlus V. A.
Published: December 2024

Quantum fluctuations of the phase difference of the order parameter of superconductors in pure S-c-S point contacts are investigated. Expressions for the effective action describing the quantum behavior of the phase difference are derived within the framework of the microscopic theory. The mean-square deviation of the magnetic flux from the classical mean value is determined for a superconducting ring containing a point Josephson junction, and the probability of quantum tunneling decay of a metastable current state is calculated.
Thermal conductivity of solid N2O and CO2
Authors: Kravchenko Yu. G. , Krupskiĭ I. N.
Published: December 2024

An experimental investigation of the thermal conductivity of solid N2O and CO2 in the premelting temperature regions has been carried out. It was established that over a wide temperature range the thermal resistivity of both crystals is described by a linear temperature dependence. It is shown that a libron contribution to the thermal resistivity of the crystals is only sufficiently evident near their triple points. Over the whole temperature range studied there is an appreciable contribution to the thermal resistivity of N2O from processes of phonon scattering by local deviations in the molecular force interaction as a result of the dipole disorder in the crystal.
Jump in the flow stress at the superconducting transition in tin single crystals
Authors: Kirichenko G. I. , Shumilin S. É.
Published: December 2024

The effect of a superconducting transition on the plastic flow of tin single crystals, monitored by the motion of dislocations through the Peierls barrier, is studied in the temperature range 0.5−3.7 K. The stress and temperature dependences of the jump in the flow stress at the N–S transition are obtained.
Magnetoelastic gap and phase transitions
Authors: Frishman A. M.
Published: December 2024

We have studied the long wavelength spectrum of coupled magnetoelastic vibrations. We obtain the dependence of the frequency on the magnitude of the wave vector for the general case without application of any model assumptions as to the form of the system energy. It is shown that in the typical case the magnetoelastic gap (the energy of activation for the quasimagnon part of the spectrum) is nonzero for all values of the external parameters, including the phase transition points. Conditions are found under which the gap may go to zero.
Theory of quantum Bose crystals
Authors: Shevchenko S. I.
Published: December 2024

An attempt is made to explain the recently observed unique plastic properties of parahydrogen: flow of crystals in a gravitational field and superplasticity—fluid-like flow under a load. A detailed microscopic study of a Bose crystal with a small number of zero vacancions is carried out. The wave function of the ground state of the crystal is found; an order parameter is introduced for the condensate fraction of the vacancions; and an equation describing slow changes in the order parameter in space and time is derived. The conditions under which vacancies can appear only near the surface of the crystal are determined. In the situation when the surface layer becomes superfluid, the density of quantum vortices accompanying the flow of transport current along the layer is calculated. The mass flowing along the surface of the crystal in the gravitational field is found.
Electrical conductivity of layered crystals in a quantizing field with scattering by acoustic phonons
Authors: Gorskii P. V.
Published: December 2024

The electrical conductivity of layered semiconductors in a quantizing magnetic field perpendicular to the layers is investigated in the case where the electric and magnetic fields are parallel to one another.
Effect of the boundary between metals on the motion of nonequilibrium quasiparticles in point contacts
Authors: Akimenko A. I. , Ponomarenko N. M. , Yanson I. K.
Published: December 2024

The point-contact spectra of the heterocontacts PrNi5−Me (Me = Cu,Ag,Au). The significant asymmetry of the spectra of the heterocontacts, observed for the first time, in the ballistic state of electron transit is explained by the kinetics of the nonequilibrium quasiparticles (phonons and excitons) on the interface between the electrodes in contact. In the diffusion state this effect is not observed.
High-temperature oscillations in uncompensated bismuth-based alloys
Authors: Bogod Yu. A. , Krasovitskii Vit. B. , Lemeshevskaya E. T.
Published: December 2024

High-temperature oscillations (HTO) in bismuth doped with tellurium and in bismuth–antimony alloys doped with tellurium and tin are studied. It is shown that the period of the oscillations, associated with a given group of charge carriers, is determined by the Fermi energy of both the electrons and the holes.
Spectral and structural studies of ferroelastic phase transitions in the layered molybdates CsDyc Eu1−c(MoO4)2
Authors: El’chaninova S. D. , Ilyushhin A. S. , Litvinenko Yu. G.
Published: December 2024

The c–T phase diagram is obtained for the system of crystals CsDycEu1−c(MoO4)2 in the range of Dy3+ concentrations from 1 to 0.6. The anisotropy of the temperature dependence of the thermal expansion coefficients in a crystal containing an impurity is observed to change. We analyze the peculiarities of the distortions that arise under first-order and second-order phase transitions. We also discuss the mechanism of phase transitions in crystals of the system CsDycEu1−x(MoO4)2 and the role of Jahn-Teller Dy3+ ions in them.
Effects of fluctuations on the tunneling conductance of tin films
Authors: Belogolovskiĭ M. A. , Khachaturov A. I. , Chernyak O. I.
Published: December 2024

The differential resistance of aluminum–insulator–tin tunneling structure is measured. The resistance is found to have peculiarities due to fluctuations of the density of one-particle states in the tin film.
Influence of a diffused impurity layer on the radio-frequency properties of thin slabs
Authors: Kolesnichenko Yu. A.
Published: December 2024

A theory of radio-frequency size effects is developed for a thin metal slab with an impurity layer near one of its faces, the impurities diffusing from a deposited film.
Combination parametric resonance of spin waves
Authors: Borovikov V. S. , Leĭfer P. N. , Frishman A. M.
Published: December 2024

The threshold of the parametric instability of spin waves is calculated as a function of external parameters when the longitudinal magnetic field has a two-frequency microwave component and a monochromatic radio-frequency component.
Characteristic features of electron–phonon scattering in thin films of semimetals
Authors: Butenko A. V. , Bukhshtab E. I. , Komnik Yu. F.
Published: December 2024

The temperature dependence of the phase interruption time of the electron wave function τϕ, determined from measurements of the localized correction to the conductivity, in semimetal films is studied. The quantity τϕ is determined by the electron-electron (τϕ−1~T) and electron-photon (τϕ−1~T2) inelastic scattering processes. The dependence τϕ(T) has a singularity at some temperature T0, below which the quadratic contribution is “frozen out.” The temperature T0 corresponds to the condition that the wavelength of the thermal phonon equals the thickness of the film.
Effect of microwave radiation power on the parameters of the current–voltage characteristics of superconducting channels
Authors: Dmitriev V. M. , Zolochevskii I. V. , Khristenko E. V.
Published: December 2024

The results of an experimental study of the effect of the power of microwave radiation on the dynamics of phase-slip centers (PSC) in superconducting channels are presented. It was established that when an electromagnetic field interacts with the samples the resistance Rd1 (P = 0) of one current PSC approaches (P ≥ Pc) = R1 (R1 is the resistance of one PSC, induced by the microwave field) as the irradiation power increases. This shows that at some power level the electromagnetic radiation plays a determining role in the formation of the PSC.
Stimulated emission of anthracene-doped diphenyl in the low-region of the low-temperature phases of the host crystal
Authors: Gorobchenko V. S. , Naboikin Yu. V. , Ogurtsova L. A. , Pokrovskaya F. S.
Published: December 2024

The two-frequency stimulated emission from an anthracene-doped diphenyl crystal is studied as a function of the temperature in the range 1.6−4.5° K. The anomalous behavior of the stimulated-emission spectrum obtained when the temperature was varied from 12 to 30° K is attributed to the existence of the low-temperature phase II in the host crystal.
Isochoric thermal conductivity of solid CO2
Authors: Konstantinov V. A. , Manzheliĭ V. G. , Levchenko A. V.
Published: December 2024

The isochoric thermal conductivity of CO2 crystals with molar volumes 27.46, 27.72, and 28.15 cm3/mole has been measured in the premelting temperature region. The observed excess in the thermal conductivity λ above the values which follow from a λ ∼ 1/T law is interpreted within the framework of a vacancy transport mechanism. The isochoric activation energies for self-diffusion Qv are determined and the isobaric QP are calculated; a discussion of the results obtained is carried out.
Features of the kinetics of the phase separation of 3He−4He solid solutions at ultralow temperatures
Authors: Mikheev V. A. , Maĭdanov V. A. , Mikhin N. P.
Published: December 2024

The kinetics of the phase separation of 3He−4He solutions has been studied at T =100 m·K by an NMR method. Specimens of solid helium containing 0.54% 3He and with molar volume 20.55 cm3/mole were investigated. An unusually long time for phase separation was found, which depended on the prehistory of the specimen. In the concentrated phase of the phase-separated solution, the spin diffusion of the 3He exhibits a quasi-one-dimensional character, with a value of the diffusion coefficient characteristic of the liquid.
Effect of pinning centers on the dynamic mixed state of superconducting Pb–Bi films
Authors: Prokhorov V. G. , Kaminskii G. G. , Tret’yachenko K. G. , Pan V. M.
Published: December 2024

The IVC (volt-ampere characteristics) and the first derivatives of the IVC of nonuniform Pb−22% Bi films were studied. It is shown that the nonlinear character of the IVC of type II superconductors in the dynamic mixed state is determined by the density of pinning centers.
Vortex-induced transverse voltage in a film
Authors: Glazman L. I.
Published: December 2024

The problem of vortex interaction in a current-loaded film is studied. This interaction can lead to the appearance of a transverse, relative to the transport current, voltage. It appears owing to the recombination of a vortex and an antivortex, which enter the films from opposite sides. The transverse current–voltage characteristic (IVC) of the film is nonmonotonic. As a result of the nonequilibrium state, when the vortices move rapidly hysteresis can appear in the IVC.
Thermodynamic oscillations in periodic magnetic-breakdown structures
Authors: Gvozdikov V. M.
Published: December 2024

The quantization rules, extending the well-known Lifshitz–Onsager relations to the case of coherent motion of electrons along a chain of orbits connected to one another by magnetic-breakdown centers, are derived. It is shown that the amplitude of the l-th harmonic of the oscillations of the thermodynamic potential in such systems differs from the corresponding quantity in the absence of magnetic breakdown by the factor Tl(W), which is a polynomial in the variable W—the probability of magnetic breakdown. The boundary values at the ends of the interval of admissible values of W equal Il(0) = (l),Il(l) = 0. In magnetic-breakdown chains, consisting of alternating small and large orbits, specific magnetic-breakdown oscillations in the factor Il (W), owing to quantum interference effects on a small orbit, appear when the areas of the orbits differ substantially.
Theory of the high-frequency properties of multisublattice, low-dimensional, relativistically noncoIlinear antiferromagnets
Authors: Krivoruchko V. N. , Stepanov A. A. , Yablonskii D. A.
Published: December 2024

The antiferromagnetic resonance frequencies, the high-frequency magnetic susceptibility tensor, and the amplitudes of normal oscillations of a quasi-two-dimensional four-sublattice antiferromagnet with a relativistically noncollinear structure are found. A comparative analysis of the dynamical properties of low-dimensional and three-dimensional four-sublattice antiferromagnets is performed. It is shown that their dynamical behavior differs substantially, and in addition the properties of the low-dimensional multisublattice systems cannot be described on the basis of models with a smaller number of magnetic sublattices.
Evolution of thermal pulses in superfluid helium
Authors: Nemirovskiĩ S. K.
Published: December 2024

The problem of the evolution of thermal pulses in He II for stepwise heat input has been solved on the basis of the hydrodynamic equations of superfluid turbulence. The results obtained are compared with experimental data on nonstationary heating of helium.
Features of the kinetics and a new mechanism for crystallization of obliquely deposited amorphous ytterbium films
Authors: Kuz’menko V. M. , Lazarev B. G. , Mel’nikov V. I.
Published: December 2024

A hitherto unobserved mechanism for the formation of double-layered amorphous–crystalline films of ytterbium at liquid helium temperature has been found. It evidently arises from a lowering of the density of obliquely deposited layers, compared with those deposited normally. The same cause explains the features found in the kinetics of the crystallization of obliquely deposited amorphous ytterbium films; higher values of the activation energy and lower values for the front velocity for avalanche crystallization.
The spectrum of hindered rotation of 14N2 and 15N2 molecules in an Ar matrix
Authors: Aleksandrovskiĩ A. N. , Kosobutskaya E. A.
Published: December 2024

A comparative analysis has been carried out between 2 and 10° K of excess linear expansion coefficients (LEC) determined experimentally for Ar−14N2 and Ar−15N2 solid solutions, due to rotational motion of the nitrogen molecules, and the corresponding values of the excess LEC calculated on the Manz model, 1 taking account of the relaxation of the lattice near the impurity molecules. A method is proposed for separating out the contributions of ortho and para nitrogen molecules to the impurity LEC of the solid solutions. It is shown that the difference between the behavior of the experimental and theoretical values of the excess LEC is determined by a feature of the lowest rotational energy level T1u namely, its splitting into a singlet and a doublet corresponding to a higher energy. The value of the energy gap between them that we determined is 4Beff ≈ 4.2° K on the Manz–Mirsky model, using values of the rotational barrier and of the renormalization coefficient of the rotational constant obtained from dilatometric studies.2
Bisolitons in one-dimensional molecular systems
Authors: Ḃrizhik L. S.
Published: December 2024

A quasione-dimensional molecular chain containing two different quasiparticles with identical parameters (e.g., two excess holes or electrons with oppositely directed spins, where their mutual Coulomb repulsion is not taken into account) is investigated in the presence of deformation interaction. It is shown that solitons described in such systems by the two-component nonlinear Schrödinger equation can form bound states (bisolitons) that are stable at low velocities.
Excitons in argon cryocrystals
Authors: Fugol’ I. Ya. , Savchenko E. V. , Rybalko Yu. I. , Ogurtsov A. N.
Published: December 2024

The thermal evolution of the exciton luminescence spectrum of argon cryocrystals has been studied for the first time in the temperature range 5−40° K. A new maximum has been discovered in the exciton luminescence spectrum and has been identified as corresponding to forbidden transitions from the Γ′3/2 states. We discuss the necessity of taking into account the polariton effects in the luminescence of argon. Self-localized, single-site excitons are proven to exist in the bulk of the sample.
Texture of 3He-B confined between rotating coaxial cylinders
Authors: Gongadze A. D. , Mikeladze S. V.
Published: December 2024

The texture of the directrix of 3He-B confined between rotating coaxial cylinders has been considered, both in the presence of vortices and in the transient regime. It is shown that in this geometry the parameters characterizing the vortex structure can be more accurately measured than in a hollow cylinder.
Liquid phase of surface electrons on helium
Authors: Buntar’ V. A. , Grigor’ev V. N. , Kirichek O. I. , Kovdrya Yu. Z. , Monarkha Yu. P.
Published: December 2024

When the parameter Γ=e2π1/2ns1/2/kt>47 the lifetime τ of surface electrons on liquid helium is much longer when the applied electric field is smaller than its equilibrium value. The increase is due to the appearance of short-range order characteristic of the liquid state.
Topological transitions in superconductors: topology, density of states, and thermodynamics
Authors: Bar’yakhtar V. G. , Zarochentsev E. V. , Lozovskii V. Z. , Khudik B. I.
Published: December 2024

Topological transitions in superconductors are studied. It is shown that a change in the topology of isoenergetic surfaces can lead to the appearance of singularities in the density of states of quasiparticles and to a nonmonotonic temperature dependence of the heat capacity.
Changes in the conducting properties of granular indium films in a metal–insulator transition
Authors: Belevtsev B. I. , Komnik Yu. F. , Fomin A. V.
Published: December 2024

The metal–insulator transition (MIT) in granular indium films, which occurs when the electron localization is enhanced as the thickness of the oxide interlayers between the granules increases, is studied. Attention is devoted primarily to the general characteristics of the change in the electric properties as the MIT is approached and the mechanisms of activated conduction in the dielectric state. It is shown based on an analysis of the experimental curves of the electric resistance versus the temperature and applied electric and magnetic fields that the dielectric state of granular indium films characteristically exhibits hopping conductivity with a variable hopping length, and in addition at sufficiently low temperaturs the conductivity is described by the Shklovskii–Éfros theory, which takes into account the existence of a Coulomb gap.
Theory of the nonlocal electromagnetic generation of ultrasound in alkali metals at low temperatures
Authors: Kaner É. A. , Fal’ko V. L , Sal’nikova L. P.
Published: December 2024

An asymptotically exact theory is developed for the process of conversion of an electromagnetic wave into an acoustic wave in a magnetic field H normal to the surface of an alkali metal. An analytical solution is obtained for an arbitrary degree of anomaly of the skin effect in both the specular and the diffuse reflection of electrons from the surface of the sample and for all values of the magnetic field preceding helicon resonance at the given frequency. The developed theory gives good qualitative correspondence with the results of all published experiments on the conversion of electromagnetic waves into sound in pure potassium at liquid-helium temperatures. Numerical calculations indicate satisfactory quantitative agreement of the theory with experiment, and this leads to the conclusion that the constant in the potential of the deformation interaction of electrons with ultrasound in potassium differs considerably from the constant in the approximation of almost-free electrons.
Conversion of homonuclear molecules in atomic cryomatrices
Authors: Strzhemechnyĭ M. A. , Tokar’ O. I.
Published: December 2024

A theory of the conversion of homonuclear molecules of the type N2 in inert gases is constructed. Underlying the conversion mechanism is the interaction of the nuclear spins of the rotator molecule with atoms of the crystal environment. Since the energy ε transferred to phonons is small, the characteristic conversion time [which is proportional to (ε/θ)3, where θ is the Debye temperature] is very long. The possibility of conversion being observed experimentally should apparently be associated with the stimulation of the conversion by paramagnetic impurities. According to the the estimates made, the characteristic time of O2-stimulated conversion is no more than 3 · 104 h, which is comparable to the conversion times in solid deuterium. The general aspects of conversion kinetics are considered and so are the most promising ways of detecting conversion in a thermal experiment.
Effect of diffusion of aluminum atoms on the magnetoresistance of thin single-crystalline molybdenum plates
Authors: Koval’ V. F. , Vatamanyuk V. I. , Ostroukhov Yu. S. , Panchenko O. A.
Published: December 2024

The effect of the diffusion of aluminum on the magnetoresistance R of thin single-crystalline molybdenum plates is studied. The magnetic field H was oriented perpendicularly to the surface of the sample H‖n‖ [100]. It was found that the period of the Sondheimer oscillations, used to determine the effective depth Δd of penetration of the impurity, changes. Its dependence on the annealing time can be represented as td1/2 and corresponds to the diffusive character of the penetration of aluminum atoms into molybdenum. It was found that R as a function of the magnetic field deviates from the law R ∼ H2 in proportion to the diffusion annealing.
Point-contact spectroscopy of metallic alloys and compounds (review)
Authors: Yanson I. K. , Shklyarevskii O. I.
Published: December 2024

The physical foundations of point-contact spectroscopy of phonons in materials with a short electron mean free path length are presented. It is shown that high-resolution point-contact spectroscopy is possible in the diffusive state of electron passage through the point contact. The dependence of the integral intensity of the point-contact spectra and the relative intensity of the peaks in the spectrum is studied as a function of the elastic electron mean free path length. The phonon features in the point-contact spectra in the presence of Joule heating of the near-contact region are studied. It is found that in heterocontacts thermoelectric effects lead to the appearance of asymmetry in the current-voltage characteristics in the thermal regime. In point contacts consisting of variable-valence compounds or Kondo lattices, the thermal regime can be realized owing to electron–electron collisions. Examples of the application of point-contact spectroscopy in the study of different alloys and compounds, demonstrating the possibility of this new experimental technique, are presented. The objects studied include ordered alloys, alloys with light and heavy impurities giving rise to local and quasilocal pnonon modes, alloys with magnetic impurities, heterophase systems, variable-valence, etc. In the case when the regime of electron passage in the point contact consisting of variable-valence compounds is close to ballistic, elastic resonance scattering of conduction electrons by localized 4f levels, enabling the reconstruction of the position of these levels relative to the Fermi level, occurs.
Excess current in superconducting wide films
Authors: Volotskaya V. G. , Sivakov A. G. , Turutanov O. G.
Published: December 2024

The resistive state arising in wide long films with the suppression of superconductivity by current flow is studied. It is established that for high transport currents a voltage-independent excess current I0 is observed on the current–voltage characteristics. Video images of the resistive state in this region of currents, obtained by the method of laser scanning, indicate that the entire film is in the resistive state. The dependence of I0 on the magnetic field and the microwave power was determined.
Investigation of the distribution of internal magnetic fields in spin glasses at zero temperature
Authors: Skafaru V. V. , Kozhukar’ S. P.
Published: December 2024

The distribution of internal magnetic fields in spin glasses at zero temperature is studied in terms of the Ising model of infinite long-range interaction. The investigation is based on the condition of ground state stability with respect to individual spin flops. This condition is enhanced by the introduction of energy barriers which should stimulate the condition of stability of the vacuum with respect to cluster flipping. The distribution of random energy barriers is described phenomenologically. Multi- and single-state distribution functions of exchange magnetic fields are obtained. The linear behavior of the single-site distribution function at small magnetic fields is shown.
Temperature dependence of the spectrum and phosphorescence decay kinetics of acenaphthenequinone-doped 1,4-dibromonaphthalene crystals
Authors: Avdeenko A. A. , Dobrokhotova V. K. , Naboikin Yu. V. , Tiunov Yu. A. , Chukanova I. N.
Published: December 2024

The behavior of the spectrum and kinetics of phosphorescence of acenaphthenequinone-activated 1,4-dibromonaphthalene crystal is studied in the temperature interval 4.2−7 K. Impurity centers that can form bound excited complexes as the temperature of the crystal is raised were discovered. A series of fundamental facts indicates that spin-selective processes in the system of Zeeman spin sublevels of the triplet state participate in the mechanism of formation of complexes.
Excitonic mechanism of electron-stimulated desorption of crystalline films of inert elements
Authors: Rashba É. I. , Sherman E. Ya.
Published: December 2024

A dynamic theory of electron-stimulated desorption of crystalline films of light inert elements (Ar, Ne), recently studied experimentally, is proposed. The quantum-mechanical model on which the calculations are based is based on exciton self-localization in the near-surface layer, and in addition the self-localization is determined by the negative work function of the electron. The solution of the dynamic equations shows that in the course of the self-localization the atoms acquire sufficient kinetic energy for detachment from the crystal.
Nature of high-frequency oscillations generated by a superconducting film with a resistive state
Authors: Gogadze G. A.
Published: December 2024

It is shown that non-Josephson oscillations can be induced in the resistive state of superconducting films by quantum transitions of quasiparticles (with photon emission) from the resonance level ε1 to the edge of the superconductor energy gap. The genesis of the level ε1 is associated with interference effects between quasiparticles scattered by the boundaries of a phase-slip center. Electrons acquire this energy in the electric field generated by the phase-slip center, as a result of multiple Andreev reflection processes. The temperature dependence of the oscillation frequency qualitatively confirms the experimental data.