jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Tomoyuki Onuma | N. ONO | Satoshi Okamoto
Source: Journal of the Magnetics Society of Japan (article, 2024-12-31)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Feature Analysis on Iron Loss Behaviors of Various Soft Magnetic Cores under DC Bias Fields To realize a highly efficient power converter, it is very important to reduce the energy loss of passive magnetic components such as transformers and inductors in the high frequency region. Core loss behavior under DC bias magnetic fields is crucial for characterizing inductor performance. Various core loss behaviors have been reported so far, that is, the iron loss of some cores decreases with the DC bias fields while that of the others increases. These various core loss behaviors under DC bias fields have not been fully elucidated. In this study, the parameters for core loss behaviors under DC bias fields were investigated through the feature extraction of B-H curves of various soft magnetic cores with different materials and different permeabilities. Principal component analysis revealed that the slope and curvature of B-H curves are major components that are strongly correlated with core loss. Changes in the slope and curvature were found to positively and negatively contribute to core loss, respectively. Therefore, the various core loss behaviors under DC bias fields are understood to be a consequence of these two competitive factors. Feature (linguistics) ; Materials science ; Pattern recognition (psychology) ; Computer science ; Artificial intelligence Magnetic Properties and Applications ; Non-Destructive Testing Techniques ; Induction Heating and Inverter Technology
Authors: Carsten Speckmann | Kimmo Mustonen | Diana Propst | Clemens Mangler | Jani Kotakoski
Source: arXiv (Cornell University) (preprint, 2024-11-05)
Field: Materials Science — Materials Chemistry

Electron-irradiation effects on monolayer MoS2 at elevated temperatures The effect of electron irradiation on 2D materials is an important topic, both for the correct interpretation of electron microscopy experiments and for possible applications in electron lithography. After the importance of including inelastic scattering damage in theoretical models describing beam damage, and the lack of oxygen-sensitivity under electron irradiation in 2D MoS2 were recently shown, the role of temperature has remained unexplored on a quantitative level. Here we show the effect of temperature on both the creation of individual defects as well as the effect of temperature on defect dynamics. Based on the measured displacement cross section of sulphur atoms in MoS2 by atomic resolution scanning transmission electron microscopy, we find an increased probability for defect creation for temperatures up to 150°C, in accordance with theoretical predictions. However, higher temperatures lead to a decrease of the observed cross sections. Despite this apparent decrease, we find that the elevated temperature does not mitigate the creation of defects as this observation would suggest, but rather hides the created damage due to rapid thermal diffusion of the created vacancies before their detection, leading to the formation of vacancy lines and pores outside the measurement's field of view. Using the experimental data in combination with previously reported theoretical models for the displacement cross section, we estimate the migration energy barrier of sulphur vacancies in MoS2 to be 0.26 +- 0.13 eV. These results mark another step towards the complete understanding of electron beam damage in MoS2. Monolayer ; Irradiation ; Electron ; Materials science ; Chemistry ; Nanotechnology ; Physics ; Nuclear physics 2D Materials and Applications ; MXene and MAX Phase Materials ; Chalcogenide Semiconductor Thin Films
Authors: Dr. Mark Roberts | Derek Schuurman | Porter P. Lowry II | Lucienne Wilmé | Patrick O. Waeber
Source: Madagascar Conservation & Development (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

Madagascar’s proposed domestic rosewood trade undermines species protection and exposes fatal flaws in the CITES regime Madagascar’s proposal to expand its domestic trade in rosewood by allowing the use of logs from its “official” stockpiles, which have been embargoed, undermines international conservation efforts and exposes critical weaknesses in the CITES regime. Despite the listing of all Malagasy rosewood species on CITES Appendix II and the implementation of a trade moratorium, illegal exports of rosewood persist, driven by criminal syndicates exploiting gaps in enforcement and forest governance. The proposal to remove 30,000 logs from CITES jurisdiction, purportedly for domestic use, lacks adequate safeguards to prevent their diversion into international markets and trade. This move threatens to set a dangerous precedent for other countries, potentially facilitating illegal trade in other rare or endangered species. Immediate, stringent oversight and effective enforcement mechanisms are essential to mitigate these risks and uphold global conservation objectives. La proposition de Madagascar d'élargir son commerce intérieur de bois de rose en autorisant l'utilisation des grumes provenant de ses stocks « officiels », qui avaient été placés sous embargo, compromet les efforts internationaux de conservation et révèle des faiblesses critiques dans le régime de la CITES. Malgré l'inscription de toutes les espèces de bois de rose malgache à l'Annexe II de la CITES et la mise en place d'un moratoire sur leur commerce, les exportations illégales de bois de rose persistent, alimentées par des réseaux criminels exploitant les failles de l'application des lois et de la gouvernance forestière. La proposition de retirer 30 000 grumes de la juridiction de la CITES, soi-disant pour un usage domestique, ne présente pas les garanties suffisantes pour empêcher leur détournement vers les marchés internationaux illégaux. Cette mesure risque de créer un précédent pour d'autres pays, en facilitant potentiellement le commerce illégal d'autres espèces rares ou en danger. Une surveillance immédiate et rigoureuse, accompagnée de mécanismes d'application efficaces sont essentiels pour atténuer ces risques et maintenir les objectifs mondiaux de conservation. CITES ; Enforcement ; Listing (finance) ; Law enforcement Wood and Agarwood Research ; African Botany and Ecology Studies ; Conservation, Biodiversity, and Resource Management
Authors: L. Fleres | J. Venara | M. Cuozzo | S. Fargier | C. Mahé | E. El Haber | F. Goutelard | F. Carrel
Source: SPIRE - Sciences Po Institutional REpository (article, 2024-05-27)
Field: Materials Science — Materials Chemistry

Characterization of nuclear-irradiated graphite by non-destructive beta spectrometry using a MLEM deconvolution algorithm International audience Deconvolution ; Characterization (materials science) ; Mass spectrometry ; Graphite ; Algorithm ; Nuclear graphite ; Physics ; Radiochemistry ; Computer science ; Materials science ; Irradiation ; Nuclear physics ; Chemistry ; Optics Graphite, nuclear technology, radiation studies ; Nuclear Physics and Applications ; Electron and X-Ray Spectroscopy Techniques
Authors: М.Г. Баширов | E.M. Bashirova | I.G. Yusupova | Д.Ш. Акчурин
Source: E3S Web of Conferences (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Study of the relationship between the parameters of electromagnetic-acoustic transformation and the stress-strain state of the metal to solve the problem of remote monitoring of power equipment The implementation of Russia’s energy strategy provides for the creation of an intelligent control system for active-adaptive electrical networks of the electric power complex, which contains a system for remote diagnostic monitoring of energy equipment, including metal load-bearing structures of electrical energy generation, transmission and consumption facilities. Promising in this regard is the use of a high-performance electromagnetic-acoustic method, which allows non-contact detection of metal defects and monitoring of their stress-strain state. But existing electromagnetic-acoustic diagnostic tools do not have sufficient sensitivity and information content to solve this problem. The article presents the results of experimental studies aimed at identifying and processing informative parameters of electromagnetic-acoustic transformation for the implementation of remote diagnostic monitoring of the stress-strain state and metal damage of power equipment. Based on the research results, it was proposed to use a frequency model formed as a result of spectral analysis of the electromagnetic-acoustic transducer signal as an integral parameter characterizing the state of the metal. Acoustics ; Energy (signal processing) ; Power (physics) ; State (computer science) ; Electric power ; Transducer ; SIGNAL (programming language) ; Stress (linguistics) ; Transformation (genetics) ; Electromagnetic radiation ; Electric potential energy ; Electromagnetic interference ; Computer science ; Transmission (telecommunications) ; Sensitivity (control systems) ; Electronic engineering ; Automotive engineering ; Engineering ; Telecommunications ; Physics ; Optics Material Properties and Failure Mechanisms ; Engineering Diagnostics and Reliability ; Non-Destructive Testing Techniques
Authors: Т. Б. Никуличева | В. С. Захвалинский | I. S. Nikulin | Vitaly Vyazmin
Source:  (article, 2024-12-11)
Field: Materials Science — General Materials Science

EPOXY COMPOSITE BASED ON WHISKERS CRYSTALS CaSO4•2H2O For the functioning of business entities, a favorable economic climate is needed.The article suggests areas of action for the development of small and medium-sized businesses in various areas of action to create favorable conditions for doing business and developing the region: resources, real sector, institutional, financial, innovation, infrastructure, markets and human capital.The implementation of the proposed activities in the areas of action will allow achieving the strategic goals for the development of small and medium-sized businesses.The values of target indicators for the development of small and medium-sized businesses in the Donetsk People's Republic by 2033 are presented. Whiskers ; Epoxy ; Composite number ; Materials science ; Composite material ; Composite epoxy material Material Properties and Applications
Authors: Hakan Duman
Source: DergiPark (Istanbul University) (article, 2024-06-02)
Field: Chemistry — Analytical Chemistry

Forecasting Soybean Production in Turkey: A Comparative Analysis of Automated and Traditional Methods Türkiye’s climate and soil are well-suited for the cultivation of oilseed crops, which are of vital importance to various industries and human and animal diets. Among oilseeds, soybeans, a legume, possess a distinctive nutritional profile. While existing research covers soybean production in Türkiye, this study aims to: a) evaluate production levels using different forecasting algorithms to identify the most accurate model, and b) based on the chosen model, forecast future production and assess the current and future entrepreneurial potential of the soybean industry in Türkiye.Soybean production data (1990-2022) from TURKSTAT was divided into training (n=25) and test (n=8) sets for cross-validation. By applying univariate time series methods, including ARIMA, SES, NNAR, MN, and Naive to the training dataset, it was found that ARIMA (1,1,1) performed best according to test set RMSE values. The performance ranking (in terms of RMSE) was as follows: ARIMA (13019) &amp;lt; SES (13888) &amp;lt; Naive (14240) &amp;lt; NNAR (58393) &amp;lt; MN (80418). Notably, for this dataset, the performance of automated processes was relatively worse than that of manual methods, suggesting that relying solely on automated methods may lead to suboptimal forecasting results. These findings underscore the importance of human oversight in the use of automated algorithms for time series forecasting and highlight the need for caution when employing automated methods.The ARIMA (1,1,1) model predicts a flat trend in production from 2023 to 2032, with an initial production volume of 154 516 tonnes and a slight decline to 153 607 tonnes. This predicted stagnation implies that, in the context of economic and population growth, soybean production will fall further behind domestic demand, leading to increased import reliance. These findings are of serious importance to farmers and policymakers alike, as they can assist in the formulation of informed decisions pertaining to resource allocation, crop planning, and market strategies. Local producers may potentially benefit from increased production efficiency, improved competitiveness, and potential revenue growth by catering to both domestic and export markets. Furthermore, an understanding of these trade dynamics can assist stakeholders in identifying potential avenues for collaboration or investment within the Turkish soybean industry. Further analysis of these results is ongoing in order to gain deeper insights into the factors influencing soybean production trends in Türkiye. Production (economics) ; Computer science ; Economics Spectroscopy and Chemometric Analyses
Authors: Maksym Omelian
Source: Mechanics and Advanced Technologies (article, 2024-12-26)
Field: Materials Science — General Materials Science

Finite-element two-stage modelling of stress-strain state parameters of a planar truss with parallel chords This paper investigates a planar truss with parallel belts made of VCt3ps steel. The stress-strain state (SSS) of such a truss is studied using a two-stage numerical modelling method based on the application of LIRA-SAPR 2016 R5 and ANSYS Workbench 14.5 software packages.The main problem is to improve the accuracy of determining the parameters of the stress-strain state of flat trusses, which will reduce their material consumption and design complexity. This will facilitate the optimization of manufacturing processes in construction and engineering.The paper proposes a two-stage modelling methodology that involves the use of two software packages. At the first stage, a finite-element model is created in LIRA-SAPR, where the preliminary parameters of the SSS are determined. At the second stage, this model was detailed in ANSYS Workbench. Critical zones in the truss nodes where stresses are maximum were identified, which is key for further design.The modelling efficiency is due to the integration of data from both software packages. This makes it possible to compensate for the limitations of each of them separately, in particular in modelling nodes with stress concentrations. The methodology provides visibility of the stress-strain state parameters, which contributes to the effective analysis of the data obtained.The work demonstrates the effectiveness of a two-stage approach to modelling the stress-strain state, which has made it possible to achieve efficiency in determining the parameters of the stress-strain state of a truss. The combination of LIRA-CAD and ANSYS allows to effectively take into account both the overall strength characteristics of the structure and local deformations and stress concentration zones.The results of the study can be applied in the construction of industrial and public buildings, bridges, as well as in other industries, including mechanical engineering, where parallel girders are used. The methodology ensures the optimisation of material costs and labour costs during design, which is critical for large-scale engineering projects. Truss ; Planar ; Finite element method ; Stress (linguistics) ; Stress–strain curve ; Structural engineering ; Computer science ; Engineering Material Properties and Applications ; Innovations in Concrete and Construction Materials ; Advanced Theoretical and Applied Studies in Material Sciences and Geometry
Authors: Nabilah Abdul Samad | Dayang Norulfairuz Abang Zaidel | Nor Alafiza Yunus | Ida Idayu Muhamad | Yanti Maslina Mohd Jusoh | Daniel Joe Dailin | Joko Sulistyo
Source: Journal of Advanced Research in Fluid Mechanics and Thermal Sciences (article, 2024-02-04)
Field: Materials Science — Materials Chemistry

Kinetics Modelling of Moringa Oleifera Leaves using Microwave Drying The drying kinetics of (Moringa Oleifera) leaves were studied at various microwave power levels (300, 500, 800, and 1000 W) using an existing drying mathematical model. The best-fitted mathematical models of the drying curves were determined by considering the coefficient of determination (R2), SSE, and RMSE based on the experimental drying data of moringa leaves. For drying M. oleifera leaves, three out of six models exhibited the optimum drying behaviour with the highest R2 and lowest SSE and RMSE values, with R2, SSE, and RMSE values ranging from 0.92-0.98, 0.09-0.3, and 0.06-0.10, respectively. Besides, the effective moisture diffusivity of moringa oleifera leaves during microwave drying varied from 1.56 × 10-8 to 5.49 × 10-8 m2/s. The values of D0 and Ea from microwave drying of Moringa oleifera leaves were estimated as 9.0 x 10-8 m2/s and 17.53 W/g. Moringa ; Microwave ; Environmental science ; Botany ; Chemistry ; Biology ; Engineering ; Food science Thermal and Kinetic Analysis ; Moringa oleifera research and applications
Authors: Jan Rimbala | Jan Kynčl | Jan Koller | Ghaeth Fandi
Source: Energies (article, 2024-09-09)
Field: Materials Science — Materials Chemistry

Utilizing Connection of Multiple Peltier Cells to Enhance the Coefficient of Performance Peltier cells are commonly used in low-power cooling applications, such as automotive refrigerators and electronics temperature regulation systems. These applications are typically low-energy in nature. There is currently a growing emphasis on energy conservation and waste heat utilization in the energy industry. This paper explores the possibility of improving the heating or cooling coefficient of performance (COP) of Peltier cells through intelligent serial and parallel connections. The purpose of this work is to raise the question of whether it would be possible to reconsider the concept of harnessing the “energy” potential of Peltier cells. The utilized model is in line with the current state of the art, and the case study is based on parameters measured on a commercially available Peltier cell. The resulting COP, when considering current materials, remains inferior to the COP of compressor-based heat pumps. For low-power devices, it can represent a technically and economically comparable solution. Connection (principal bundle) ; Thermoelectric effect ; Materials science ; Computer science ; Mathematics ; Mechanical engineering ; Physics ; Engineering ; Thermodynamics Advanced Thermoelectric Materials and Devices ; Advanced Battery Technologies Research ; Energy Harvesting in Wireless Networks
Authors: P C Ayu | K Alfi | A Salsabila | Karina Nola Sinamo | Nur Ulina Warnisyah Sebayang
Source: IOP Conference Series Earth and Environmental Science (article, 2024-11-01)
Field: Chemistry — Analytical Chemistry

Authentication of arabika and robusta Mandailing coffee based on NIR spectroscopy and PCA method Abstract Flavor of coffee is influenced by so many factors, from the cultivation, the harvesting to the processing stage. Beside that, the variety will also provide a difference in its flavor and also price. It will be very detrimental, from economic perspective, if there is a mixing between the arabica and robusta coffee in one place. As we know to separate both arabica and robusta beans can not be done in a fast way mechanically. Therefore, a fast, objective and non destructive analysis is needed to be performed in order to address the authenticity issue of coffee beans. This study was using NIR Spesctroscopy and PCA method to classify the coffee based on its variety. Result showed that, both the arabica and robusta coffee beans could be separated 100% without any data pretreatment. This also is strengthen by the chemical data from proximate content which showed that four components showed a significant difference in both coffee varieties. Spectroscopy ; Authentication (law) ; Chemistry ; Analytical Chemistry (journal) ; Environmental science ; Chromatography ; Geography ; Physics ; Archaeology Spectroscopy and Chemometric Analyses ; Coffee research and impacts ; Food Chemistry and Fat Analysis
Authors: Hui‐Fen Huang | Jian-Yuan Wang
Source: Preprints.org (preprint, 2024-07-29)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Terahertz Dielectric Metasurface for Reconfigurable Multifunctional Holographic Imaging with Dual-Mode Controlled by Graphene Metasurface constitutes one of the most promising technologies for holographic imaging; however, the work for terahertz (THz) metasurface holographic imaging is relatively limited. Here, we propose a THz dielectric geometric-propagation phase metasurface, which can operate dual-mode (reflection and transmission) and reconfigurable multifunctional holographic imaging. The dual-mode is realized by controlling the Fermi energy level (Ef) of the graphene integrated into the metasurface unit, and the reconfigurable three-channel holographic imaging in reflection or transmission mode are achieved by switching the feed polarization among left-handed circular polarization (LCP), right-handed circular polarization (RCP) and linear polarization (LP). The metasurface is designed based on the transmission mode, and a physical model for switching to the reflection mode is established. For the first time to the best of our knowledge, a reflection-transmission dynamic modulation THz holographic imaging metasurface has been developed. The holographic metasurface operates in transmission mode at Ef = 0.1 eV, and in reflection mode at Ef = 0.9 eV. Compared with recently published holographic imaging metasurfaces, the proposed metasurface offers the following advantages: high holographic efficiencies (42.5% to 49%), more holographic imaging channels, dynamic modulation dual-mode operations, and reconfigurability. Holography ; Terahertz radiation ; Optics ; Reconfigurability ; Polarization (electrochemistry) ; Reflection (computer programming) ; Transmission (telecommunications) ; Optoelectronics ; Materials science ; Dielectric ; Physics ; Computer science ; Telecommunications Metamaterials and Metasurfaces Applications ; Antenna Design and Analysis ; Millimeter-Wave Propagation and Modeling
Authors: David Vargas-Cano | Federico Félix Hahn Schlam | José Luis Rodríguez de la O | Alejandro F. Barrientos-Priego
Source: Revista Brasileira de Fruticultura (article, 2024-01-01)
Field: Chemistry — Analytical Chemistry

‘Ataulfo’ mango maturity index prediction using the AS7262 spectral sensor Abstract ‘Ataulfo’ mango is highly produced in Mexico, being harvested when it reaches its physiological maturity. This process takes at least another month for the fruit to reach consumption maturity. Warehouses and markets present important losses as the ready-to-eat status is unknown. Maturity status is determined by measuring slow and destructive physicochemical variables. An optical device based on the AS7262 spectral sensor was connected to the ESP32 microcontroller and measurements were correlated with soluble solids content (SSC), dry matter (DM) and firmness of mangoes obtained from the local market. Data analysis was carried out by partial least squares (PLS) regression, classification, regression tree (CART) and random forest (RF) models. With PLS, SST and firmness were predicted with R2 of 0.61 and 0.76, respectively. The root mean squared error of prediction (RMSEP) was 0.91 for SSC and 0.67 for firmness. With the CART model, classification accuracy was 90% for SSC and 87% for firmness of intact mango fruits. Index (typography) ; Maturity (psychological) ; Statistics ; Mathematics ; Horticulture ; Computer science ; Biology ; Psychology ; World Wide Web Spectroscopy and Chemometric Analyses ; Advanced Chemical Sensor Technologies ; Smart Agriculture and AI