bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid one-pot microwave-assisted synthesis and defect engineering of UiO-66 for enhanced CO2 capture
Authors: Kang Dong A. , Mohamed Amro M. O. , Murphy Christian , Ramos Andres , Economou Ioannis G. , Kim Jinsoo , Jeong Hae-Kwon
Published: November 2024

UiO-66 and its derivative consisting of zirconium oxide clusters and terephthalate-based linkers stand out as some of the most extensively studied MOFs for various applications owing to their exceptional stability.
RGAM: A refined global attention mechanism for medical image segmentation
Authors: Ning Gangjun , Liu Pingping , Dai Chuangye , Sun Mingsi , Zhou Qiuzhan , Li Qingliang
Published: November 2024

Attention mechanisms are popular techniques in computer vision that mimic the ability of the human visual system to analyse complex scenes, enhancing the performance of convolutional neural networks (CNN). In this paper, the authors propose a refined global attention module (RGAM) to address known shortcomings of existing attention mechanisms: (1) Traditional channel attention mechanisms are not refined enough when concentrating features, which may lead to overlooking important information. (2) The 1‐dimensional attention map generated by traditional spatial attention mechanisms make it difficult to accurately summarise the weights of all channels in the original feature map at the same position. The RGAM is composed of two parts: refined channel attention and refined spatial attention. In the channel attention part, the authors used multiple weight‐shared dilated convolutions with varying dilation rates to perceive features with different receptive fields at the feature compression stage. The authors also combined dilated convolutions with depth‐wise convolution to reduce the number of parameters. In the spatial attention part, the authors grouped the feature maps and calculated the attention for each group independently, allowing for a more accurate assessment of each spatial position’s importance. Specifically, the authors calculated the attention weights separately for the width and height directions, similar to SENet, to obtain more refined attention weights. To validate the effectiveness and generality of the proposed method, the authors conducted extensive experiments on four distinct medical image segmentation datasets. The results demonstrate the effectiveness of RGAM in achieving state‐of‐the‐art performance compared to existing methods.
Open data for modelling the impacts of electric vehicles on UK distribution networks: Opportunities for a digital spine
Authors: Flower Isaac , Li Furong , Padget Julian
Published: November 2024

This paper provides a detailed overview of the current snapshot of available open data for modelling the impacts of electric vehicles (EVs) on the UK distribution network, highlighting opportunities for a digital spine. We are the first to review open data available for UK distribution networks, focusing on spatial data. We also explore data for census small geographies, vehicle ownership, EV charger locations and data on their usage. Several issues are identified, including inconsistencies in dataset availability, file naming conventions, feature definitions and geographic discrepancies. We specifically analyse EV charger connection data for secondary distribution substations from two UK Distribution Network Operators (DNOs). The validity of the data is assessed by comparing it to known public charger locations from OpenChargeMap. While one DNO provides data coverage for >95% of its substations, it is valid for only 24.1% of substations with at least one public charger. Conversely, the other DNO provides data coverage for 1% of its substations due to privacy‐related obfuscation, with data valid for 98.3% of substations with at least one public charger. Addressing these challenges through standardised data‐sharing practices and implementing a digital spine could enhance the accuracy and reliability of EV‐grid integration models. These improvements are essential for facilitating the seamless integration of EVs into the grid and supporting the transition to a sustainable energy system.
IMP‐DETR: Optimization model for defect detection of injection‐moulded products
Authors: Liu Anzhan , Han Lei
Published: November 2024

Injection‐moulded products may have a variety of defects in production. Failing to detect and fix the defects may reduce product quality and lead to safety issues. An injection‐moulded product defect detection model, injection‐moulded product‐detection transformer (IMP‐DETR), is proposed to address the challenges of diversity, small size, and complex background in injection‐moulded products. The model constructs a feature extraction backbone network with the inverted residual mobile block module to extract key information and reduce interference from irrelevant backgrounds while maintaining lightweight. The small object fusion pyramid feature fusion network is used to capture rich texture information from small objects to improve the detection performance of fuzzy and small‐sized defects. Additionally, the Conv3XC‐Fusion module is designed to resolve the problem of integrating multi‐scale features, improving the stability of detection. Due to the lack of publicly available datasets for injection‐moulded product defects, custom dataset containing 2500 defect images was constructed. The experimental results indicate that the mean average precision of the IMP‐DETR model reaches 82.4%. Compared to other benchmark object detection models, IMP‐DETR demonstrates superior detection performance and a smaller model size, which is suitable for application in real scenarios.
Sustainable Gastronomy and Disaster Vulnerability in Majalengka District
Authors: Putri Dias Pratami , Bridha Risya Ladiva , Insani Hurry Mega , Hindayani Purna , Priatini Woro , Tsaniah Ilmiati
Published: November 2024

The study addressed sustainability and vulnerability in hazards in Majalengka District, focusing on the gastronomic sector. Sustainable gastronomy emphasizes environmental responsibility, social equity, and economic viability in food production until consumption. Sustainable gastronomic tourism is a crucial component of sustainable tourism development, but its durability may be compromised by a natural hazards. This study analyze the relationship between sustainable gastronomy and vulnerability to hazards in Majalengka District. The research involved mapping the distribution of culinary tourism places, vulnerability analysis, and stakeholder interviews. The method used is the Geographic Information System (GIS) method, assisted by the Global Positioning System (GPS), determine locations, with hazard data from INARISK. The results showed that the distribution of culinary tourism in Majalengka Regency is not always related to the level of vulnerability to natural hazards. The analysis revealed that gastronomic location is related to vulnerability to extreme weather disasters. Additionally, factors such as accessibility, risk planning and management, and community participation, play an important role in the sustainability of the gastronomic sector. This research is crucial for formulating sustainable tourism development strategies that consider hazard vulnerability, enhancing our understanding of sustainable gastronomic tourism’s potential to mitigate and adapt to natural hazards in Majalengka Regency.
Banana blossom as a local resource-based emergency food innovation fusion food product
Authors: Bridha Risya Ladiva , Putri Dias Pratami , Priatini Woro , Sabila Salwa Siti , Tsaniah Ilmiati , Insani Hurry Mega
Published: November 2024

This research aims to explain the innovation of emergency food products based on “Fusion Food” which uses banana blossoms as the main ingredient. Banana blossoms, a local and underutilized ingredient abundant in tropical regions, are the focus. In the context of food crises and natural disasters, innovation in emergency food products becomes increasingly important. The study combines banana blossoms with various ingredients to create a nutritious, long-lasting emergency food. Researchers conducted experiments in processing banana blossoms and combining them with other ingredients with interesting flavors and textures. The results of the research on the experimental design tested three formulations in organoleptic tests on 30 semi-trained panelists to see the level of preference (hedonics) for one of the recipe formulations. The Banana Heart Samosa SJP2 received the highest preference score of 4.14. The frozen banana blossom samosas have a shelf life of over three months, with optimal consumption within three months. Half-cooked samosas last less than three days in the refrigerator, under nine hours unrefrigerated, and cooked samosas last less than two days. This research highlights the significance of innovative emergency food products that meet nutritional needs and offer diverse flavors, potentially enhancing food security during emergencies.
Mapping Schools Vulnerability to Earthquakes: Case Study of Cianjur Earthquake 21 November 2022
Authors: Yani Yani , Tusam Mohamad , Larasaty Dwi , Isnaini Nur
Published: November 2024

Earthquakes are unpredictable disasters that cause a lot of damage, such as the destruction of infrastructure and casualties. Indonesia has a high level of earthquake risk. One of the earthquakes that occurred was the Cianjur earthquake in November 2022, caused by the movement of the Cugenang fault. This earthquake caused many houses and public facilities, including schools, to be damaged. This study aims to map schools that are vulnerable to earthquakes as one of the early warning systems to improve disaster preparedness. The classification is based on the earthquake vulnerability map provided by BMKG. The research method used is Geographic Information System (GIS). Data from the earthquake hazard map and the distribution of schools were then analyzed using the overlay technique. From the results of this processing, three earthquake hazard zones were determined, namely the forbidden zone, the restricted zone, and the conditional zone. There are two schools with a percentage of 6.45% in the forbidden zone, seven schools with a percentage of 22.58% in the restricted zone, and 22 schools with a percentage of 70.97% in the conditional zone. More schools are in the conditional zone; therefore, it is necessary to increase earthquake disaster awareness.
Understanding The Scope of Regional Geography: A Perspective from Indonesia’s Geographic Region
Authors: Astari Annisa Joviani , Aliyan Silmi Afina , Bratanegara Alnidi Safarach , Muslim Ahmad Bukhori , Nurawaliyah Vira Islami , Mohamed Assem Abdelmonem Ahmed
Published: November 2024

Studying the regional geography of one country means expanding all associat ed physiographic and human aspects, as well as their interrelation and distributions. This study aims to seek an answer to what actually the scope of geographic region to b e studied to understand one country’s geographic region. We took Indonesia as a case as Indonesia has a very unique geographic position as well as its archipelago. The met hod of this research is using content analysis from related literatures, and from the results of forum group discussions as well as short survey to the foreign summer cours e participants regarding the Indonesia’s geographic region. The results of this study shown the scopes have been identified including the territorial boundaries, continent boundary, administrative border, and its position; physical and landscape; biodiversit y and natural resources; marine resources; the culture: ethnic groups, languages, arts, customs; natural disasters and tourism. Those scopes have been found effective and a ttractive for the participants who joint the summer program. Nevertheless, we also inc luded how the global connectedness to the Indonesian geographic region as a new perspe ctive of regional geography.
Impact of kampung siaga bencana on increasing disaster preparedness in the community of West Bandung regency
Authors: Pratiwi Rahayuni Tyas , Rohmat Dede , Ruhimat Mamat
Published: November 2024

The focus of this research is to look at the impact of Kampung Siaga Bencana on improving community disaster preparedness in Cipada Village and Cililin Village, both in West Bandung Regency. Cipada Village and Cililin Village are the only villages in West Bandung Regency that are designated as Kampung Siaga Bencana. This study is based on the Kampung Siaga Bencana theory, which is a community-based disaster mitigation technique. The descriptive method and quantitative methodology are used in this study. Questionnaires and interviews were used to collect data, which was then analyzed using statistics. The findings revealed that 1) the Kampung Siaga Bencana influence on Cipada Village was only 0.33 or less than 0.5. This implies that the value of the impact or relationship between disaster preparedness villages and readiness is low value. 2) The research findings for Cililin Village are 0.773 or greater than 0.5. This indicates that the the impact or interaction between Kampung Siaga Bencana and Cililin Village preparedness is quite significant. In conclusion, there are differences in the results in the two villages because Cililin Village is a disaster-prone village, and many Kampung Siaga Bencana programs are implemented and applied well in the village. In contrast to Cipada Village, which is not prone to disasters.
Spatial modeling for estimating land prices of new autonomous region candidates lembang city
Authors: Wulandari Ervika Putri , Fahrezi Agil Akbar , Fachri Hana Taqiyyah , Arrafi Muhammad , Arrasyid Riko
Published: November 2024

The population in Indonesia which reaches ± 268 million people causes the population’s need for land to increase. Land has an important role in the development of area, all aspects of development will be related to the need for land. Lembang as one of the sub-districts that is predicted to be a New Regional Candidate which will be used as a research area to determine land prices. For mapping is used by Geographic information system method based on several parameters. The preparation consists of literature review and data collection, in process of inputting data into GIS is used scoring for the data analysis step. The results obtained have five classes of land price estimates consisting of very low, medium, high, and very high land price estimation classes. The land value zone in CDOB Lembang City varies, starting from the highest price in the range of Rp. 16,020,000 20,000,000, and the lowest in the range of Rp. 100,000 – 4,080,000. The price of this land is quite varied, but in accordance with the conditions of land use and tourism conditions which are quite varied too.
Spatial Structure of Accomodation Distribution In Belitong Unesco Global Geopark
Authors: Fitriyani E. , Wulung S.R.P. , Abdullah C.U. , Yuliawati A. K. , Rahayu A. N. E. , Fadilah M.A.N
Published: November 2024

The purpose of this study is to map the geographical distribution of lodging in Belitung, a popular tourist site that is where the spice route is being rebuilt. The amount of accommodations, which included homestays, non-star hotels, and star hotels, was examined using a variety of geographic data analysis techniques. Up till 2021, 88 lodgings were found. Additionally, according to the findings of mapping the availability of lodging, these accommodations were located in relation to region, natural conditions, and growth stages of the tourism destination, offering additional value to prepare lodging for the development of Belitong Unesco Global Geoparks.
Evaluation of Machine Learning Models for Mapping Food Crops using Sentinel-2A Imagery in West Java, Indonesia
Authors: Ridwana Riki , Kamal Muhammad , Arjasakusuma Sanjiwana , Rabbi Muh Fiqri Abdi
Published: November 2024

Data on the distribution patterns and locations of food crops are crucial for monitoring and controlling the sustainability of agricultural resources and guaranteeing food security. Plant classification based on machine learning has been widely used to detect food crop areas. However, there are still challenges in mapping plant types and plant area effectively and efficiently. The aim of this research is to evaluate machine learning models in mapping and calculating the area of food crops (rice) in West Java Province, Indonesia. Google Earth Engine is used in this study as a big data cloud computing platform for remote sensing. Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) Sentinel2A imagery is utilized to employ time series data as input characteristics for the three most popular machine learning models: Support Vector Machine (SVM), Random Forest (RF), and Classification and Regression Trees (CART). The research results show that the three machine learning models are able to map and calculate the area of food crops in West Java, Indonesia. The RF algorithm produces the highest overall accuracy rate (98.51%) and is the fastest in the accuracy assessment and image classification process compared to the SVM and CART algorithms.
Economic recovery of cultural tourism village communities affected by Covid-19 using the SDGS program
Authors: Supriadi Acep , Supriyono  , Nugraha Dadi Mulyadi , Gumelar Abih , Nur Muhammad
Published: November 2024

The Covid-19 pandemic has had an impact on the economy of cultural tourism village communities. The aim of this research is to formulate and analyze strategic steps for economic recovery of cultural tourism village communities through village government policies. This needs to be done considering the impact of the Covid-19 pandemic which has resulted in economic difficulties for the cultural tourism village community. The recovery of the community’s economy towards a new normal period needs to be carried out immediately so that it does not impact cultural tourism village destinations. This research uses a case study method in Rancakalong District, Sumedang Regency. Data collection techniques were obtained through literature studies and online interviews with village officials, tourism village managers and local communities. The analysis was carried out qualitatively by reducing the data resulting from research findings. The research results show that the economic recovery of cultural tourism village communities can be carried out with the policy of 1) Providing guidance to small business actors; 2) providing creative economy business capital loan assistance; and 3) training in marketing village cultural tourism products and destinations globally.
Bibliometric analysis: Research trends of environmental literacy in higher education from 2019 to 2023
Authors: Arif Muhammad
Published: November 2024

Environmental literacy needs to be provided to prospective teacher students. The ability to environmental literacy will help future teachers manage environmentally-based learning. The purpose of this research is to describe the forms of environmental literacy teaching and the instruments used to assess the environmental literacy of prospective teacher students. This research is a bibliometric study. A total of 85 pieces of literature were found in the search using the Publish or Perish (PoP) application from 2019 to 2023, and after a literature analysis process, 22 articles were deemed relevant to answer the research questions. The results of this research show that the forms of environmental literacy improvement courses used in higher education are: 1) providing materials followed by real environmental problem-solving projects, 2) providing materials followed by pedagogic projects, 3) project-based learning using microcontroller technology, 4) STEM-oriented learning, and 5) inquiry-based learning. The instruments used include multiple-choice tests, interviews, and questionnaires. Environmental literacy improvement-oriented learning is widely applied to students majoring in elementary education, science education, and biology education.
Urban Heat Island Study Based on Remote Sensing and Geographic Information System: Correlation between Land Cover and Surface Temperature
Authors: Somantri Lili , Himayah Shafira
Published: November 2024

Significant changes in urban environmental characteristics such as altered land use and a higher population density contribute to the formation of the urban heat island (UHI) phenomena. Remote sensing technology and Geographic Information Systems (GIS) have now become effective tools for analysing the UHI phenomenon. This research uses the literature review method. The objectives of this study were to review: 1) General studies of the UHI phenomenon, 2) UHI studies in the context of remote sensing and GIS, and 3) Application GIS and remote sensing to examine the connection between surface temperature and land cover in the context of urban heat island effects. The UHI is formed related to the change in urban structure and land cover, such as an increase in building and road surfaces and a reduction in green open areas. The UHI phenomenon has significant impacts on thermal comfort, air quality and energy efficiency in urban areas. UHI measurements can be made by analyzing Land Surface Temperature (LST). LST can giver information on change in time and space of the Earth’s surface temperature. This review can offer a more thorough comprehension of the variables influencing UHI. and its impact on the urban environment as well as a collection of technical remote sensing and GIS methods that can be applied to map the UHI phenomenon.
Building extraction from unmanned aerial vehicle imagery using Mask-RCNN (case study: Institut Teknologi Sepuluh Nopember, Surabaya)
Authors: Ramadhani Anisa , Alya Nurul Fitri
Published: November 2024

Due to their individual shape, form, texture and colour variations, the automatic extraction of a building from high-resolution aerial photographs continues to be complicated. The Mask Region-based Convolutional neural network (Mask R-CNN) has shown recent improvements in object detection and extraction for updating data, which are superior to other methods. In this paper, a dataset consisting of aerial photography images acquired by aircraft in the urban and educational area of Institut Teknologi Sepuluh Nopember Surabaya to explore the potential of using Mask R-CNN, the art model, for instance, segmentation to automatically detect building footprints, which are essential attributes that define the urban fabric (which is critical to accelerating land cover updates with high highly accurate in terms of area and spatial assessment). The objective of this study was to implement Artificial Intelligence, especially with the Mask-RCNN method to perform building footprint detection. To enable this, aerial imagery was clipped into chip-sized images as training data for the model to learn. The model appeared to result in 73% precision. The model also shows the loss value graph, which represents the data well. Further study could focus on improving the precision of the model, which could also improve the result better.
Revealing Sukamandi Village as a sustainable tourism destination in Subang Regency, Indonesia
Authors: Rahman Gilang Nur , Dede Moh. , Sukriah Erry , Pratama Armandha Redo , Anggasta Giovani , Mukaromah Choirunisa , Muhammad Kautsar , Widiawaty Millary Agung , Rosita Rosita , Marhanah Sri
Published: November 2024

Sukamandi Village in Subang Regency, Indonesia, demonstrates significant potential for developing nature-based tourism as part of national and regional initiatives to promote community welfare. This research aims to reveal Sukamandi village as a sustainable tourism destination in Subang Regency. We used a qualitative approach to assess Sukamandi’s tourism potential, utilizing field surveys, interviews, literature reviews, and tourist satisfaction data. The research reveals that Sukamandi Village possesses strong natural attractions, primarily Bukit Jamali and Curug Cibingbin, complemented by picturesque mountain vistas, clear rivers, clove plantations, and local agricultural products. A trial itinerary with six local and international tourists yielded positive feedback, particularly regarding scenic views and local cuisine. However, the study identifies several challenges hindering optimal tourism development: 1) Tourism management remains largely voluntary, lacking a professional team for consistent, high-quality service; 2) Limited accessibility, with small roads and considerable distances between attractions, poses logistical challenges; 4) Inadequate internet and cellular connectivity affects the tourist experience to upload their activities. To realize Sukamandi’s full tourism potential and drive local economic growth, the study recommends enhancing physical and digital accessibility, upgrading infrastructure, implementing comprehensive disaster risk management, and increasing tourism promotion efforts.
Activity Space for Online Activities: An Opportunity for Building Resilience in Industry 4.0 Era and Post-Covid-19 Pandemic
Authors: Puspita Iredo Bettie , Kurniawan Andri , Marfai Muh Aris
Published: November 2024

Industry 4.0 era and the Covid-19 pandemic have driven a transformation in online activities, enabling people to engange in various tasks from anywhere, which in turn has altered spatial behavior. This study explored the correlation between the characteristics of online activities and the choice of activity space represented in land use patterns. The study classifies online activities into seven clusters using the SelfOrganizing Mapping (SOM) introduced by Kohonen. The spatial distribution of these clusters is visually represented on a land-use map overlay. The study employs Contingency Coefficient C analysis to assess the correlation between online activity characteristics and space selection. The results of data analysis of online activity actors in Semarang City and Yogyakarta City showed that the online activities were spatially distributed at random. This is supported by a chi-square significance value above 0.05 and a Contingency Coefficient C value around 0.3, indicating no significant correlation between the characteristics of online activities and space choice. These findings suggest that online activities can be conducted anywhere, without specific spatial requirements, thereby reducing physical exposure in urban areas. The reduced physical exposure of an area was one indicator of urban resilience from the physical and environmental aspects.
Development of interactive multimedia based on lectora inspire to improve understanding about disaster mitigation material in senior high school
Authors: Wirda Tria Rahma , Sugandi Dede
Published: November 2024

Media that gives pupils a comprehensive grasp is necessary to improve comprehension of disaster mitigation content. One of the teaching strategies that can raise the standard of geography instruction is information and communication technology-based learning. An application for creating interactive learning multimedia and e-learning content is called Based Lectora Inspire. The purpose of this study was to: (1) develop and find out the feasibility of interactive multimedia based on Lectora inspire about disaster mitigation materials as a geography learning medium (2) determine the effectiveness of the Lectora inspire media that was developed to improve the results of students understanding of the material. The four steps of the Borg and Gall model needs analysis, multimedia model design, media development, and multimedia evaluation are used in this study’s Research and Development (R&D) methodology. The study’s findings indicate that: (1) With a very good category, interactive multimedia based on Lectora inspire on disaster mitigation materials can be used as a geography learning tool; (2) Lectora-inspired interactive multimedia effectively enhances comprehension of disaster mitigation content. Compared to audio-visual media, interactive multimedia based on lectora has a greater impact on enhancing comprehension of disaster mitigation in this study.
Humanitarian supply chain redesign using a GIS-based two-stage stochastic model: a case study of earthquake in Tehran
Authors: Mousazadeh Mohammad , Aminpour Mohammad Hossein
Published: November 2024

The world has experienced many natural and human-made disasters recently. Such disasters can vary from a local residence to a city or even affect a nation or broader areas. This paper presents a multi-objective mixed integer linear programming model for redesigning the humanitarian supply chain network. The proposed two-stage stochastic model optimizes some pre-disaster and post-disaster strategic and tactical decisions, i.e., the location and capacities of facilities, allocation and flow decisions, and pre-positioning strategies. The model aims at minimizing the total fixed and operational costs of the network, minimizing the total distance in the network, and maximizing the total utility of the network. The presented model is validated by examining a real case study focusing on the outbreak of an earthquake in Tehran, the capital city of Iran. Finally, the Pareto optimal solutions of the model are found using the improved augmented ε-constraint method, and some managerial implications are presented.
Stimulation and enhancement of superconductivity by external electromagnetic radiation (review)
Authors: Dmitriev V. M. , Khristenko E. V.
Published: November 2024

The results of experimental and theoretical investigations on the stimulation and enhancement of superconductivity by external electromagnetic radiation in narrow long [L > ξ (T)] and short [L < ξ (T)] specimens of Sn, In, and Al in a field of frequencies of 7 MHz to 150 GHz are given. The dependence of the effect on the size, material, and purity of the specimens is examined. The experimental results presented here as well as results obtained by other authors are shown to be in good agreement with the conclusions of the microscopic theories of Éliashberg and Aslamazov and Larkin.
Self-blocking tunnel currents and current-voltage characteristics of S-I-S tunnel contacts
Authors: Seminozhenko V. P.
Published: November 2024

Nonequilibrium states in a superconductor are considered for quasiparticle injection at eV − 2Δ ≪ 2Δ, where eV is the voltage across the contact and Δ is the energy gap. It is shown that the excess of excitations over the equilibrium value (which are localized in the main above the gap) results in a self-blocking quasiparticle tunnel current. The relative magnitude of the effect is determined by the barrier transparency and also by the thickness of the films forming the tunnel contact, as well as by the potential difference. The nonequilibrium suppression of the superconducting gap on quasiparticle injection is considered for various limiting cases. The scope for determining Δ from tunnel experiments with homogeneous contacts is discussed.
Theory of metamagnetic transitions in ErB4
Authors: Vitebskii I. M.
Published: November 2024

A model is given that describes the phase transitions in ErB4 induced by an external magnetic field along the tetragonal axis; the crystal symmetry and some additional assumptions about the nature of the phase transitions enable one to express the exchange-interaction constants in terms of the critical fields. All the rare-earth tetraborides are isomorphous, so the argument can be extended to other such compounds.
Thermal expansion of solid methane and conversion processes
Authors: Aleksandrovskii A. N. , Kokshenev V. B. , Manzhelii V. G. , Tolkachev A. M.
Published: November 2024

The thermal expansion of pure solid methane, methane containing oxygen and nitrogen impurities, and a solid solution of 75% CH4 + 25% CD4 was investigated in the temperature range 2−4°K. The temperature dependence of thermal expansion in methane of equilibrium spin modification composition was determined. The connection between the negative thermal expansion coefficient of methane and conversion processes was established experimentally, in qualitative agreement with the basic conclusions of the theoretical studies by Yamamoto and coworkers. Characteristic conversion times and their temperature dependence above 5.8°K were derived from the analysis of the variation in time with changing temperature of the dimensions of pure methane specimens. It was found that O2 and N2 impurities affect considerably the thermal expansion of methane of equilibrium spin modification composition. The orientationally disordered sublattices turned out to be more sensitive to the effect of impurities. An explanation is suggested for the influence of impurities with quadrupole intermolecular interaction on the thermal expansion of methane. A study of the methane-deuteromethane solution permitted us to find distinctive features of thermal expansion in the orientationally ordered phase of CH4.
Absorption of second sound in superfluid He3–He4 mixtures
Authors: Dikina L. S. , Kotenev G. Ya. , Rudavskii É. Ya.
Published: November 2024

Absolute measurements of the coefficient of absorption of second sound in superfluid He3–He4 mixtures with concentrations of 0.5% to 10% He3 are carried out in the temperature range from 1.3 to 2°K. It is found that at sufficiently low temperatures the absorption of second sound decreases considerably as the He3 content increases, and its temperature dependence exhibits nonmonotonic behavior with a broad absorption minimum.
Electrically controlled Josephson elements
Authors: Bevza Yu. G. , Karamushko V. I. , Kel’man É. A. , Tzach G. G. , Dmitrenko I. M.
Published: November 2024

Current-controlled cross-shaped thin-film structures are investigated. The nonstationary Josephson effect, the characteristics of which are determined by the value of the controlling current, is obtained near Tc on the current-controlled weak link. Long films that formed a cross-shaped structure had a high degree of homogeneity. The irradiation-induced critical current enhancement observed in these strips is described well by Éliashberg’s theory. After formation of the weak link the relative increase of the irradiation-induced critical current becomes larger and, simultaneously, the absolute current values decrease.
Superconductivity and phonon spectrum of the bismuth–thallium system
Authors: Svistunov V. M. , Dikii A. P. , D’yachenko A. I.
Published: November 2024

Electron tunneling in Bi–Tl films (55−90 at.% Bi) at pressures up to 12 kbar is studied experimentally. For component concentrations near that of Bi2Tl, the tunnel conductivity, which corresponds to the low-energy portion of the Bi–Tl phonon spectrum, reveals features that disappear at pressures P ≥ 3.5 kbar. These data demonstrate that there is a phonon instability near the phase equilibrium boundaries. Based on experimental data, the electron–phonon interaction functions α2(ω)F(ω) are reconstructed and on their basis changes observed in superconducting properties are analyzed.
Stability of the magnetic phases of antiferromagnets in a high-frequency magnetic field
Authors: Gerasimchuk V. S. , Gorobets Yu. I.
Published: November 2024

The influence of a high-frequency magnetic field on the stability of the magnetic phases of uniaxial antiferromagnets coexisting in spin-reorientational phase transitions of the first kind of Morin type and phase transitions of the first kind of the antiferromagnet-ferromagnet type, is investigated. It is shown that the lability fields and temperature bands of the coexistence of the magnetic phases can change substantially under the effect of a rapidly oscillating magnetic field, and the points of the phase transitions themselves can also be shifted.
Increased luminescence of the quasi-one-dimensional antiferromagnet CsMnCl3·2H2O in a magnetic field
Authors: Bron R. Ya. , Eremenko V. V. , Matyushkin É. V. , Shapiro V. V.
Published: November 2024

The influence of a strong magnetic field upon the luminescence intensity of CsMnCl3·2H2O is studied for the temperature interval 4–20°K. The observed strengthening of the luminescence is explained in terms of an excitonic luminescence mechanism induced by an external field which produces a noncollinearity of the magnetic structure.
The specific heat of layered structures
Authors: Anders É. E. , Sukharevskii B. Ya. , Shestachenko L. S.
Published: November 2024

This paper considers the effect of the distinctive features of the phonon spectrum of layered structures, i.e., the existence of a flexural branch, on their thermodynamic characteristics. A method proposed for processing experimental data on the specific heat permits important parameters of the phonon spectrum of layered crystals to be determined. Fairly good agreement is found to exist between the experimentally measured specific heat of layered crystals and that calculated with the assumption of partial excitation of degrees of freedom for the low-frequency region of the phonon spectrum within the framework of the Lifshitz model. An analysis is made of the temperature dependence of the specific heat for a number of layered substances according to the data in the literature as well the results of our own measurements of the specific heat of In4Se3 single crystals in the temperature range from 2 to 80°K.
Low-temperature statistical characteristics of moving dislocations
Authors: Vydashenko V. N. , Landau A. I.
Published: November 2024

Using computer simulation techniques, we studied the distribution function ω(α) of angles α at which a dislocation meets point obstacles (stoppers) randomly distributed in the glide plane as well as the distribution function ω(l) of dislocation segment lengths l, i.e., distances between neighboring stoppers along the dislocation. The low-temperature (T⟶0) asymptotic forms for the functions ω(α) and ω(l) are obtained, and their dependences on the number N¯ of point obstacles the dislocation is suspended upon as well as on the time interval during which the dislocation moves through the network of obstacles are studied. For comparison we present data concerning the distributions ω(α) and α (l) in the initial configuration which forms as the dislocation is suspended on the network of point obstacles at the initial moment of loading, as well as data on the high-temperature (T⟶∞) asymptotic forms of the distribution functions ω(α) and ω(l).
The dynamic behavior of the order parameter of superconductors
Authors: Makeev A. I. , Mitsai Yu. N.
Published: November 2024

The dynamic behavior of the order parameter of thin superconducting films in an electromagnetic field has been investigated. The singularities in the behavior of the order parameter at the external field frequencies ω0 = Δ/n are discussed.
Temperature dependence of the lattice thermal conductivity of certain solid solutions based on titanium, vanadium, and tantalum at low temperatures
Authors: Zlobintsev G. M. , Iliev L. B. , Kozinets V. V. , Merisov B. A. , Ogneva É. M. , Ovcharenko V. I. , Pervakov V. A.
Published: November 2024

The lattice thermal conductivity of certain solid solutions based on titanium, vanadium, and tantalum was measured over the 5−50 °K temperature range. Here its electron and lattice components are separated. The lattice component in all materials is found to follow the relation λL~Tn below 10 °K. The power exponent is different for each base metal. These differences are interpreted in terms of the model of transition metals with impurities [J. Ziman, Electrons and Phonons, Inostr. Lit., Moscow (1962) p. 488; N. Morton, Cryogenics 17, 335 (1977)].
Investigation of the electrical resistivity of bismuth crystal whiskers under tension
Authors: Gaidukov Yu. P. , Danilova N. P. , Shcherbina-Samoilova M. B.
Published: November 2024

The dependences of the resistivity without a magnetic field and the quantum oscillation frequencies during strains of the simple tension type are investigated simultaneously in bismuth crystal whiskers at 4.2 °K. Four kinds of anomalous resistivity changes are detected. It is shown that a change in Fermi surface topology can be accompanied by anomalies in the behavior of the resistivity at the same time as anomalies not accompaned by a change in Fermi surface topology are possible.
Average ion pair formation energy in liquid and solid xenon
Authors: Obodovskii I. M. , Pokachalov S. G.
Published: November 2024

The current-voltage characteristics of a gridded parallel plate ionization chamber filled with liquid or solid xenon are studied under irradiation with 137Cs γ rays. The mean free path of the electrons in condensed xenon was found to exceed 50 cm. The values obtained for the average energy of ion pair formation were WCr = 12.1±0.3 eV for the crystal and Wl = 13.6±0.2 eV for the liquid.
Magnetoacoustic size effects in the intermediate state of superconductors
Authors: Bezuglyi E. V.
Published: November 2024

Features of acoustic absorption in the intermediate state of a superconducting metal with a complex conduction electron dispersion law are investigated theoretically for an arbitrary frequency and orientation of the sound wave vector. Giant oscillations on open orbits are detected. The generality of the mechanism for the origination of thermomagnetic and magnetoacoustic effects in the intermediate state due to the presence of a periodic “superstructure” in momentum space is established.
Limiting critical transverse magnetic fields of gallium
Authors: Lazarev B. G. , Semenenko E. E. , Tutov V. I.
Published: November 2024

The limiting transverse critical magnetic fields of distorted thin (90 – 40 Å) films of gallium are investigated. It is found that the maximum critical fields necessary for total breakdown amount to 180,000 Oe and the coefficient A = 3.5 (Hc = A. 104Tc). Thus, for the maximum distortion of ultrathin layers of gallium, the value of the critical magnetic field exceeds the paramagnetic limit. Based on the investigations carried out, the assumption was made that layers of thickness 90 Å are formed in the γ- modification. The superconductivity temperature after annealing to 100–150°K of gallium layers, with a thickness of less than 90 Å, increases and the maximum value of Tc of the annealed layers amounts to 7.6°K. There are no transformation processes for these layers. Spin-orbit scattering for gallium is approximately a factor of 3 less than for bismuth. The density of states with reduction of thickness of the gallium layers also is reduced.
The excited triplet state of nitrogen A3Σu+ in cryogenic crystals
Authors: Poltoratskii Yu. B. , Fugol’ I. Ya.
Published: November 2024

A study was made of the distinctive features of the Vegard–Kaplan transition in the spectral region from 3000 to 1700 Å in pure crystalline nitrogen and in solutions with inert elements. Relations are obtained for the dependence of the concentration quenching of luminescence from high-lying vibrational levels and a mechanism of vibrational relaxation is proposed. An analysis is made of the temperature and concentration effects as well as the magnitude of the matrix displacement. A possible mechanism for the occurrence of a triplet structure of vibronic bands is discussed.
Spatial separation of opposite charges and formation of dipole complexes in stratified 3He–4He liquid solutions
Authors: Monarkha Yu. P.
Published: November 2024

It is proposed that stratification of 3He–4He liquid solutions be used for spatial separation of opposite charges and for the formation of new neutral quasiparticles with a large dipole moment (diplons) in helium. The diplon binding energy is calculated and collective excitations in the proposed system are considered. An analysis is made of the new experimental capabilities which may be provided by such quasiparticles for the study of the surface properties of quantum fluids.
Liquid-crystal phase transition in a system of surface electrons at temperatures below 0.3°K
Authors: Rybalko A. S. , Esel’son B. N. , Kovdrya Yu. Z.
Published: November 2024

An inflection is observed in the pressing electric field dependence of the mobility of electrons localized on the surface of liquid helium at temperatures below T = 0.3°K. The position of this inflection is determined by temperature and charge concentration. It is shown that the inflection corresponds to a liquid to crystal phase transition in the surface electron system. The observed change in the character of the mobility dependence upon transition to a crystalline electron structure agrees well with theoretical concepts.
Taxonomy of the Nicotiana megalosiphon species complex (Solanaceae; Nicotiana section Suaveolentes): analyses of RADseq data identifies a new cryptic species
Authors: Chase Mark W. , Christenhusz Maarten J. M. , Cauz-Santos Luiz A. , Dodsworth Steven , Palsson Ruth , Conran John G. , Nollet Felipe , Samuel Rosabelle
Published: November 2024

The Nicotiana megalosiphon Van Heurck & Müll.Arg. species complex has been shown to be composed of several morphologically cryptic species similar to N. simulans N.T.Burb. Using phylogenetic and population genetic approaches (maximum likelihood, co-ancestry, admixture proportions, Bayesian species delimitation and coalescent methods), we demonstrate that there is an additional undescribed species in this complex. The species limits of N. latifolia M.W.Chase & Christenh., N. latzii M.W.Chase, R.W.Jobson & Christenh., N. megalosiphon, N. sessilifolia (P.Horton) M.W.Chase & Christenh. and N. simulans, previously circumscribed based solely on a phylogenetic approach, are confirmed in the new analyses and a new species, N. palssonae M.W.Chase & Christenh., is described. A map of species distributions and a key to the species of the N. megalosiphon species complex are provided.
Soundin(g(k)) ethnic in Toronto
Authors: Walker James A.
Published: November 2024

Research on ethnolects tends to focus on qualitative salient features rather than quantitative differences in
variables shared across the speech community. This study examines ethnolinguistic variation in the realization of word-final velar
nasals in the English of Toronto, Canada. Over 4,000 tokens were extracted from sociolinguistic interviews with 50 residents of
Toronto stratified by ethnicity, generation and sex, and coded for a series of linguistic and social factors. While speakers
largely share linguistic conditioning, there are significant differences between social groups. A language-transfer explanation is
not supported by comparing ethnic orientation scores with overall rates. An explanation based on intersecting social factors
receives support by examining participant levels of education. Findings suggest that the meaning of velar nasals cuts across
several social dimensions.
Degree of foreign accent and contrastive characterization
Authors: Kashkarova Polina
Published: November 2024

Past research on American telecinematic media suggested that foreign-accented English often marked contrastive
characters. However, studies addressing Hollywood’s representations of individual groups of non-native speakers of English have
been scant. Moreover, although the degree of foreign accent in character depiction was commented on, apparently being meaningful,
it was not systematically assessed. This article analyzes the use of various degrees of foreign accentedness in the portrayals of
Russian characters in 36 Hollywood films released in the post-Soviet period. Focusing on contrastive roles, determined as
negative, criminal, and comic, the study identifies their correlation with stronger foreign accents. In addition, characters with
elite occupations display a higher degree of foreign accentedness than characters with mainstream occupations, which is explained
by the less perceived threat of the latter, hence, less need to be cast as a linguistic other. The findings indicate that the
accent portrayals of Russians in American cinema are biased and reflect a broader standard language ideology in the US. The study
also provides support for the supposition that negative attitudes toward Russian English in the US are prompted by unfavorable
images of cinematic Russians.