bluuebunny/crossref_metadata_2025 huggingface dataset:
Hematodinium perezi (Dinophyceae: Syndiniales) in Morocco: The First Record on the African Atlantic Coast and the First Country Record of a Parasite of the Invasive Non-Native Blue Crab Callinectes sapidus
Authors: Lamkhalkhal Amal , Rahmouni Imane , Selfati Mohamed , Hamid Aicha , Kmentová Nikol , Vanhove Maarten P.M. , Bazairi Hocein
Published: June 2024

Dinoflagellates belonging to the genus Hematodinium are key parasites of marine crustaceans, primarily decapods. In this study, we document the first report of H. perezi Chatton & Poisson, 1930 on the African Atlantic coast. This is also the first parasite record in the invasive non-native Atlantic blue crab Callinectes sapidus Rathbun, 1896 in Morocco. Specimens of C. sapidus were sampled in winter 2023 from two Ramsar sites on the Moroccan Atlantic, namely Merja Zerga and Oualidia Lagoons, and were screened to detect the presence of parasites in their hemolymph. Based on staining fresh hemolymph smears, we did not detect Hematodinium in any of the 36 investigated individuals (20 and 16 from Merja Zerga and Oualidia Lagoons, respectively), probably due to methodological artifacts. The PCR-based method was revealed to be more accurate in diagnosing the Hematodinium parasite. It showed that at Merja Zerga Lagoon, 13 individuals of C. sapidus were infected by the parasite (prevalence: 65%) in comparison to four at Oualidia Lagoon (25%). Genetic analysis, based on the ITS1 rDNA gene from Hematodinium, confirmed the sequences as being those of Hematodinium perezi.
Fully Coupled Hydrodynamic–Mooring–Motion Response Model for Semi-Submersible Tidal Stream Turbine Based on Actuation Line Method
Authors: Wang Guohui , Zhang Jisheng , Lin Xiangfeng , Chen Hao , Wang Fangyu , Liu Siyuan
Published: June 2024

The modeling of floating tidal stream energy turbine (FTSET) systems demands significant computational resources, especially when incorporating fully coupled models that integrate hydrodynamics, mooring, motion response, and their interactions. In this study, a novel hybrid numerical model for FTSET systems has been developed, utilizing the open-source software OpenFOAM. The hydrodynamic characteristics of three-bladed vertical-axis turbines are simulated in steady, three-dimensional wave–current numerical tanks using an unsteady actuator line method (UALM). The interFoam two-phase Navier–Stokes solver within OpenFOAM is utilized to manage the kinematic characteristics of the floating platform. Mooring dynamics are addressed using the mass–spring–damper model (MoorDyn), and turbine wake dynamics are resolved using a buoyancy-modified RANS turbulence model. The comprehensive model can simulate wave, flow, mooring dynamics, platform motion, and the interactions between the turbine and platform within FTSET systems. To validate the model, several scenarios are analyzed, and experiments are conducted to validate the numerical results. The model accurately predicts platform motion responses and mooring line tensions, especially under wave–current conditions, capturing the interconnected effects of platform motion during turbine rotation. Additionally, the model extends predictions of turbine–platform wake development and interaction.
An Experimental Study on Estimating the Quantity of Fish in Cages Based on Image Sonar
Authors: Zhu Guohao , Li Mingyang , Hu Jiazhen , Xu Luyu , Sun Jialong , Li Dazhang , Dong Chao , Huang Xiaohua , Hu Yu
Published: June 2024

To address the highly demanding assessment of the quantity of fish in cages, a method for estimating the fish quantity in cages based on image sonar is proposed. In this method, forward-looking image sonar is employed for continuous detection in cages, and the YOLO target detection model with attention mechanism as well as a BP neural network are combined to achieve a real-time automatic estimation of fish quantity in cages. A quantitative experiment was conducted in the South China Sea to render a database for training the YOLO model and neural network. The experimental results show that the average detection accuracy mAP50 of the improved YOLOv8 is 3.81% higher than that of the original algorithm. The accuracy of the neural network in fitting the fish quantity reaches 84.63%, which is 0.72% better than cubic polynomial fitting. In conclusion, the accurate assessment of the fish quantity in cages contributes to the scientific and intelligent management of aquaculture and the rational formulation of feeding and fishing plans.
Immediate Radiological Risk Evaluation after a Hypothetical Radioactive Off-Site Release Event
Authors: Lobato Ana Carolina Lodi , Gavazza Sérgio , Santos Avelino , Curzio Rodrigo Carneiro , Andrade Edson R.
Published: June 2024

This study used an analytical computational model to evaluate safe zones in contaminated areas that may result from a hypothetical significant off-site release from a nuclear power plant. The model, considering local atmospheric stability, wind direction, and location, calculates the expected total effective dose equivalent (TEDE) and potential safety zones. This research, focused on an area near a nuclear facility affected by an accidental release, used SCALE and HotSpot Health Physics codes to simulate the reactor’s core inventory content and off-site release. This study’s findings underscore that the risk of developing solid cancer (testing morbidity) is influenced by both local atmospheric stability and the composition of the potentially affected population (primarily age and sex). These findings, backed by an analytical approach, can significantly influence logistical and operational planning. The utilization of computer simulations can also aid in creating flexible response scenarios to real events.
Chronic Pelvic Pain in Congestion Pelvic Syndrome: Clinical Impact and Electromyography Pelvic Floor Activity Prior to and after Endovascular Treatment
Authors: Corvino Fabio , Giurazza Francesco , Coppola Milena , Tomasello Antonio , Coletta Francesco , Sala Crescenzo , Villani Romolo , de Martino Bernardo Maria , Corvino Antonio , Niola Raffaella
Published: June 2024

Background: This study aims to characterize the clinical impact of endovascular treatment in Chronic Pelvic Pain (CPP) patients due to Pelvic Congestion Syndrome (PCS) and to assess the diagnostic value of surface electromyography (sEMG) studies of pelvic floor musculature (PFM) in PCS patients pre- and post-endovascular treatment. Between January 2019 and July 2023, we studied consecutive patients who were referred for interventional radiology assessment and treatment to a tertiary trauma care hospital, had evidence of non-obstructive PCS from Magnetic Resonance Imaging (MRI), had sEMG of PFM and who had undergone endovascular treatment. The primary outcome was clinical, defined as a change in symptom severity after endovascular treatment. The secondary outcome was a difference in the sEMG values pre- and post-endovascular therapy. Results: We included 32 women (mean age 38 years). CPP was the leading symptom in 100% patients, followed by dysmenorrhea (75%) and post-coital pain (68.7%). Endovascular therapy included ovarian vein embolization in 28 patients (87.5%) and internal iliac vein embolization in only 2 patients (6.2%). After a median of 8 (range 6–10) months from endovascular treatment, 29 (90%) of patients reported an improvement of the main symptoms, and 15 (46%) were symptom-free. The sEMG values did not show a statistical difference pre- and post-PCS endovascular treatment. Conclusions: Endovascular treatment appeared to be highly effective in CPP due to PCS and was associated with a low rate of complication. sEMG study could be useful in revealing alterations of PFM electrophysiology, but a difference pre- and post-embolization in PCS patients was not demonstrated.
Data Model for the Comprehensive Management of Biobanks and Its Contribution to Personalized Medicine
Authors: Sánchez-López Ana María , Catalina Purificación , Franco Fernando , Panadero-Fajardo Sonia , Rejón Juan David , Romero-Sánchez María Concepción , Puerta-Puerta Jose Manuel , Aguilar-Quesada Rocío
Published: June 2024

Biobanks are infrastructures essential for research involving multi-disciplinary teams and an increasing number of stakeholders. In the field of personalized medicine, biobanks play a key role through the provision of well-characterized and annotated samples protecting at the same time the right of donors. The Andalusian Public Health System Biobank (SSPA Biobank) has implemented a global information management system made up of different modules that allow for the recording, traceability and monitoring of all the information associated with the biobank operations. The data model, designed in a standardized and normalized way according to international initiatives on data harmonization, integrates the information necessary to guarantee the quality of results from research, benefiting researchers, clinicians and donors.
Mechanisms of Stimulation of Small- and Medium-Sized Entrepreneurship: The Experience of Kazakhstan
Authors: Kazbekova Damira , Petrova Mariana , Sushchenko Olena , Belgibayeva Anargul , Mitkov Milen
Published: June 2024

This study aimed to investigate the prerequisites, factors, and mechanisms for stimulating economic growth in small and medium-sized enterprises (SMEs), using the manufacturing industry of the Republic of Kazakhstan as a case study. Econometric tools, including statistical methods, regression analysis, time series analysis, scenario development methods, and the decision tree method, were employed to analyze the data. This research employed a range of scientific and applied methods, resulting in practical outcomes that can be utilized by SMEs to model various development scenarios. The key factors influencing SME development, such as the costs of technological innovations, average monthly wages, level of innovative activity, and investments in fixed capital, were identified. Based on these factors and the diagnosis of the state, a mechanism for state stimulation of entrepreneurship, encompassing financial incentives, tax breaks, infrastructure support, and targeted training programs, was developed. This mechanism includes a system of incentives, goal-setting, and tool formation. This study also developed a model to evaluate the potential impact of measures at the regional level on production volume growth in the manufacturing industry, presenting three scenarios—pessimistic, realistic, and optimistic—for consideration, which are significant for policymakers, practitioners, and stakeholders in the field. Stakeholders, including investors and industry practitioners, can apply the recommended strategies to foster innovation and drive economic growth. This study provided actionable recommendations and a robust framework for stimulating SME growth, offering valuable insights for enhancing the economic resilience and industrial development of Kazakhstan.
A Nature-Inspired Partial Distance-Based Clustering Algorithm
Authors: El Habib Kahla Mohammed , Beggas Mounir , Laouid Abdelkader , Hammoudeh Mohammad
Published: June 2024

In the rapidly advancing landscape of digital technologies, clustering plays a critical role in the domains of artificial intelligence and big data. Clustering is essential for extracting meaningful insights and patterns from large, intricate datasets. Despite the efficacy of traditional clustering techniques in handling diverse data types and sizes, they encounter challenges posed by the increasing volume and dimensionality of data, as well as the complex structures inherent in high-dimensional spaces. This research recognizes the constraints of conventional clustering methods, including sensitivity to initial centroids, dependence on prior knowledge of cluster counts, and scalability issues, particularly in large datasets and Internet of Things implementations. In response to these challenges, we propose a K-level clustering algorithm inspired by the collective behavior of fish locomotion. K-level introduces a novel clustering approach based on greedy merging driven by distances in stages. This iterative process efficiently establishes hierarchical structures without the need for exhaustive computations. K-level gives users enhanced control over computational complexity, enabling them to specify the number of clusters merged simultaneously. This flexibility ensures accurate and efficient hierarchical clustering across diverse data types, offering a scalable solution for processing extensive datasets within a reasonable timeframe. The internal validation metrics, including the Silhouette Score, Davies–Bouldin Index, and Calinski–Harabasz Index, are utilized to evaluate the K-level algorithm across various types of datasets. Additionally, comparisons are made with rivals in the literature, including UPGMA, CLINK, UPGMC, SLINK, and K-means. The experiments and analyses show that the proposed algorithm overcomes many of the limitations of existing clustering methods, presenting scalable and adaptable clustering in the dynamic landscape of evolving data challenges.
The Improving of Sky Gardens’ Environmental Quality from a Health Promotion Perspective
Authors: Li Yan , Du Hongwu
Published: June 2024

The quality of landscape space directly influences public health behaviors, making public assessments of the qualities of the sky garden landscape crucial for optimizing it. This article focuses on three types of typical high-rise building sky garden (plaza-park, rest-stay, and move-pass type) and establishes an evaluation framework for their health promotion characteristics (24 indicators in 7 dimensions) based on existing restorative environment research. Then, questionnaires (354 valid responses) and quantitative calculations were employed to assess the public’s perception of demand in health behaviors and the spatial supply of different sky garden types. Ultimately, the data were processed to propose targeted interventions and recommendations to enhance health benefits using the comprehensive importance-performance analysis method. The results show the following: (1) The public seems to have widely accepted sky gardens in the context of high-density urban environments (near 6.92, below the mean of 7.09). They place greater emphasis on spatial indicators that cater to relaxation activities and show heightened sensitivity toward public facilities (7.32–8.00) that contribute to physical and mental health-related activities. (2) The health promotion performance of different types of sky garden shows significant variation, with the rest-stay sky gardens at the embodied scale demonstrating the greatest competitive advantage. (3) The development of sky gardens has significant potential, and different types of sky garden need to specifically lever-age their characteristics as complementary public spaces.
Protected Areas in the Brazilian Amazon Threatened by Cycles of Property Registration, Cattle Ranching, and Deforestation
Authors: Candino Malena , Brandão A. , Munger J. , Rausch L. , Gibbs H. K.
Published: June 2024

Protected areas (PAs) in the Brazilian Amazon have proven to be critical in preserving the rainforest but face increasing threats. Since 2019, illegal activities and land conflicts involving PAs have escalated due to the weakening of environmental institutions. Therefore, up-to-date research is needed to evaluate agricultural pressures on PAs—including Sustainable Use Areas, Indigenous Territories, and Strictly Protected Areas—given its importance in driving deforestation in the Amazon, and to identify hotspots of concern. We analyzed property registration, deforestation, pasture expansion, and cattle transaction records within 158 PAs in the Brazilian state of Pará, which holds most of the remaining forest and the highest rates of deforestation. Our findings show that nearly a quarter of Pará’s 2019–2022 deforestation occurred within PAs, undermining their effectiveness as conservation tools. Despite prohibitions, we found illegally registered private properties in most PA categories including indigenous territories and over a 100% increase in deforestation within PAs from 2015–2018. Over 90% of PAs contained pasturelands in 2022, but only half of them had registered cattle transactions within their borders, which suggests the presence of clandestine cattle activities in these areas as well. Indirect sales to slaughterhouses coming from PAs increased during the study period, potentially due to efforts by ranchers to obscure such cattle origins from companies that are increasingly monitoring their direct suppliers. Finally, we identified 17 high-risk PAs concentrating most threats. Focusing monitoring efforts on property registries and cattle transactions in these areas could significantly reduce illegal deforestation and illegal cattle ranching. While PAs are considered to be cornerstones of forest conservation efforts, our findings show that current policies fail to prevent cycles of land grabbing, illegal ranching, and deforestation that can eventually lead to the downgrading, downsizing, and degazetting of PAs. Given this context, validating property claims, tracing cattle sales, and penalizing deforestation are urgently needed to halt these cycles that threaten PAs.
Spatial Digital Twin Architecture for the Field Design Process of Oil and Gas Projects in Australia
Authors: Bhandari Sijan , Paudyal Dev Raj , Chadalavada Sreeni
Published: June 2024

This paper aims to develop a conceptual system architecture utilising the land survey data model (LSDM) to manage spatial information associated with field design for oil and gas projects. A widely accepted design science research approach was used, which includes five phases as the foundation phase, development phase, implementation phase, demonstration phase, and validation phase. The developed system architecture consists of five major components: data classes and categories, a data management system, map servers, a visualisation system, and users. This study utilised Unified Modelling Language (UML) diagrams, such as use case, and sequence diagrams to illustrate the relationship between the developed architecture and the field design process and demonstrate workflow and its interaction with stakeholders. A prototype was developed to demonstrate the viability of developed conceptual system architecture. Furthermore, a study area situated near a mining town Chinchilla at the Western Down Regional Council, Queensland, Australia, was selected to validate the prototype in the real world. This study provides a theoretical contribution towards Industrial Revolution 4.0, aiding enhanced decision-making processes within the oil and gas industry and the more effective management of energy resources.
Empowering Rural Development: Evidence from China on the Impact of Digital Village Construction on Farmland Scale Operation
Authors: Zhao Shaoyang , Li Mengxue , Cao Xiang
Published: June 2024

In the global context of rural development in developing countries, the integration of digital technology into agriculture has emerged as a pivotal strategy for modernizing rural areas and boosting agricultural productivity. A focal point of policy initiatives, digital village construction aims to harness digital technology to empower rural development. Despite widespread recognition of its potential benefits for agricultural development, empirical evidence on its specific impacts, particularly on farmland scale operation, remains scarce. This study investigates the relationship between digital village construction and farmland scale operation in China, leveraging data from Sichuan Province’s rural revitalization strategy and Peking University’s Digital Village Index. Our analysis reveals a significant enhancement in farmland scale operation, particularly in non-poverty and non-border villages, after addressing potential endogeneity in the estimation. Mechanism analysis demonstrates that digital village construction drives scaled operation and management through improved agricultural production efficiency, the establishment of agricultural industry systems, and the advancement of agricultural engineering projects. However, its impact varies across village types, underscoring potential disparities in rural development. These findings suggest that continued investment in digital village construction is essential to stimulate rural development, focusing on leveraging digital technologies to enhance agricultural productivity and providing targeted support for remote and underserved rural areas to bridge the digital gap and foster inclusive growth.
Family Language Policy in the Estonian Diaspora in Finland: Language Ideology and Home Language Education
Authors: Aksinovits Larissa , Verschik Anna
Published: June 2024

The article deals with family language policy (FLP) among Estonian families in Finland. The focus is on language beliefs concerning maintenance of Estonian and Estonian home language (HL) classes provided by municipalities free of charge. Using the classical three-component model of FLP by Spolsky (language beliefs, language management, language practices), the analysis concentrates on language beliefs (the importance of Estonian and HL education) and management (real actions that enable children’s involvement in HL classes). The data were collected from eight Estonian families via semi-structured interviews. The caregivers have higher education and stable incomes. All participants emphasized the importance of proficiency in Estonian for their ethnolinguistic identity and the beneficial aspects of HL classes. However, we found discrepancies between beliefs and actual behavior: the children do not attend Estonian HL classes because of complicated logistics and, according to the caregivers, poor language teaching methods (this claim is not supported by any evidence). Such discrepancies between beliefs and management have been attested in various recent studies of other minorities.
Ocimum sanctum as a Source of Quorum Sensing Inhibitors to Combat Antibiotic Resistance of Human and Aquaculture Pathogens
Authors: Issac Abraham Sybiya Vasantha Packiavathy , Arumugam Veera Ravi , Mary Nancy Immaculate , Dharmadhas Jeba Sweetly , Sundararaj Rajamanikandan , Devanesan Arul Ananth , Rajamanickam Ramachandran , Veerapandian Raja , John Bosco John Paul , Danaraj Jeyapragash
Published: June 2024

Biofilms play a decisive role in the infectious process and the development of antibiotic resistance. The establishment of bacterial biofilms is regulated by a signal-mediated cell–cell communication process called “quorum sensing” (QS). The identification of quorum sensing inhibitors (QSI) to mitigate the QS process may facilitate the development of novel treatment strategies for biofilm-based infections. In this study, the traditional medicinal plant Ocimum sanctum was screened for QS inhibitory potential. Sub-MICs of the extract significantly affected the secretion of EPS in Gram-negative human pathogens such as Escherichia coli, Pseudomonas aeruginosa PAO1, Proteus mirabilis, and Serratia marcescens, as well as aquaculture pathogens Vibrio harveyi, V. parahaemolyticus, and V. vulnificus, which render the bacteria more sensitive, leading to a loss of bacterial biomass from the substratum. The observed inhibitory activity of the O. sanctum extract might be attributed to the presence of eugenol, as evidenced through ultraviolet (UV)-visible, gas chromatography-mass spectroscopy (GC–MS), Fourier transformer infrared (FTIR) spectroscopy analyses, and computational studies. Additionally, the QSI potential of eugenol was corroborated through in vitro studies using the marker strain Chromobacterium violaceum.
Dissolution Thermodynamics and Preferential Solvation of Phenothiazine in Some Aqueous Cosolvent Systems
Authors: Martínez Fleming , Peña María Ángeles , Jouyban Abolghasem
Published: June 2024

Published equilibrium mole fraction solubilities of phenothiazine in ethanol, propylene glycol and water as mono-solvents at several temperatures were investigated to find standard apparent thermodynamic quantities of dissolution mixing and solvation based on the van’t Hoff and Gibbs equations. Further, by processing the reported mole fraction solubility values of phenothiazine in some aqueous cosolvent mixtures at T/K = 298.2, the inverse Kirkwood–Buff integrals treatment demonstrated preferential hydration of phenothiazine in water-rich mixtures and preferential solvation of this agent by cosolvents in mixtures of 0.24 < x1 < 1.00 in the {ethanol (1) + water (2)} mixed system and mixtures of 0.18 < x1 < 1.00 in the {propylene glycol (1) + water (2)} mixed system.
Microstructural, Mechanical and Tribological Behaviors of Cu/LLDPE-Based Composite Coatings for Lightweight Applications
Authors: Ben Difallah Basma , Bouaziz Ayda , Horovistiz Ana , Kharrat Mohamed , Dammak Maher , Cardoso César , Pereira António
Published: June 2024

This research work focuses on the development and analysis of copper-filled linear low-density polyethylene (LLDPE) coatings deposited on LLDPE substrate via a thermocompression process. A dry mechanical mixing technique is employed to mix the copper–LLDPE powders. This relevant technology aims to develop new solid lubricating layered composite coatings without a negative environmental impact. Four different materials of the coatings are considered, i.e., LLDPE + 2 wt.% Cu, LLDPE + 6 wt.% Cu, LLDPE + 10 wt.% Cu and LLDPE + 20 wt.% Cu. The microstructural characterizations indicate a good degree of dispersion and adhesion between the continuous and dispersed phases at 20 wt.% Cu coatings. The mechanical properties of the pure polymer and the fully filled composite materials are investigated experimentally using tensile tests and Micro-Vickers hardness. The stiffness, hardness and mechanical strength of the composites are enhanced. Friction tests are also carried out via a linear reciprocating sliding tribometer. The incorporation of copper powder has a significant improvement on the friction and wear properties of the developed coatings. Higher copper powder loading provides a lower friction coefficient and wear volume loss. The best tribological performances are obtained with the LLDPE + 20 wt.% Cu coating. The wear mechanism of the LLDPE substrate is severe adhesive wear, and it becomes mild abrasive wear in case of the 20 wt.% Cu coating.
Synthesis of 2-[(3,4,5-Triphenyl)phenyl]acetic Acid and Derivatives
Authors: Mazik Monika , Seidel Pierre
Published: June 2024

New phenylacetic acid derivatives with potentially valuable biological activities and the ability to act as starting materials for various functionalizations have been prepared by a multi-step synthesis. Starting from 2,6-dibromo-4-methylaniline, the synthetic route involves the construction of the basic aromatic structure (3,4,5-triphenyltoluene) (two steps), followed by its conversion into 2-[(3,4,5-triphenyl)phenyl]acetic acid and derivatives (up to five steps). Based on this multi-step synthesis, five compounds not previously reported in the literature were synthesized; the literature-known 3,4,5-triphenyltoluene was synthesized for the first time in the manner described. This synthesis is applicable for the preparation of numerous new representatives of this class of compounds.
N-Methoxycarbonyl-9,12-Dimethoxy-Norchelerythrine: A Novel Antifungal Type-III Benzo[c]phenanthridine from Zanthoxylum simulans Hance Seedlings
Authors: Cárdenas-Laverde Diego , Quiroga Diego , Coy-Barrera Ericsson
Published: June 2024

Zanthoxylum simulans Hance, commonly known as Sichuan pepper, is a well-known medicinal plant recognized for its potential as a source of bioactive specialized metabolites. As part of our interest in natural antifungal compounds, the present study describes the discovery of an unreported N-alcoxycarbonylbenzo[c]phenanthridinium salt, N-methoxycarbonyl-9,12-dimethoxy-norchelerythrine 1 (a type-III benzo[c]phenanthridine), isolated from Z. simulans seedlings, which were propagated under controlled greenhouse conditions. Six-month seedlings were harvested and subjected to cold acid–base extraction. Chromatographic techniques achieved the isolation of 1 from raw alkaloid extract. The structural elucidation of 1 was accomplished through comprehensive spectroscopic analysis, including nuclear magnetic resonance and high-resolution mass spectrometry. Fusarium oxysporum, a fungal pathogen responsible for substantial agricultural losses, was exposed to different concentrations of the novel compound, exhibiting potent antifungal efficacy (IC50 < 3 µM) and fungicide effects. These findings highlight the potential of benzophenanthridines as antifungal leads and underscore the importance of exploring natural products for agricultural applications.
The Integration of ANN and FEA and Its Application to Property Prediction of Dual-Performance Turbine Disks
Authors: Li Yanqing , Zhang Ziming , Cheng Junyi , Liu Zhaofeng , Yin Chao , Wang Chao , Guo Jianzheng
Published: June 2024

Regulating the microstructure of powder metallurgy (P/M) nickel-based superalloys to achieve superior mechanical properties through heat treatment is a prevalent method in turbine disk design. However, in the case of dual-performance turbine disks, the complexity and non-uniformity of the heat treatment process present substantial challenges. The prediction of yield strength is typically derived from the analysis of microstructures under various heat treatment regimes. This method is time-consuming, expensive, and the accuracy often depends on the precision of microstructural characterization. This study successfully employed a coupled method of Artificial Neural Network (ANN) and finite element analysis (FEA) to reveal the relationship between the heat treatment process and yield strength. The coupled method accurately predicted the location specified and temperature-dependent yield strength based on the heat treatment parameters such as holding temperatures and cooling rates. The root mean square error (RMSE) and mean absolute percentage deviation (MAPD) for the training set are 50.37 and 3.77, respectively, while, for the testing set, they are 50.13 and 3.71, respectively. Furthermore, an integrated model of FEA and ANN is established using a Abaqus user subroutine. The integrated model can predict the yield strength based on temperature calculation results and automatically update material properties of the FEA model during the loading process simulation. This allows for an accurate calculation of the stress–strain state of the turbine disk during actual working conditions, aiding in locating areas of stress concentration, plastic deformation, and other critical regions, and provides a novel reliable reference for the rapid design of the turbine disk.
Effect of Temperature on the Removal of Interferences in the Voltammetric Procedure for the Determination of Cr(VI)
Authors: Grabarczyk Malgorzata , Wardak Cecylia
Published: June 2024

The aim of this paper was to investigate the effect of temperature on the removal efficiency of surfactant-induced interferences. Surfactants were removed as a result of mixing with XAD-7 resin. The study was carried out using the example of Cr(VI) determination by adsorption stripping voltammetry (AdSV). Measurements were carried out using a solution containing Cr(VI), acetate buffer (pH = 6.2), DTPA, KNO3, and different surfactants. Ten mL of the solution was mixed with 0.5 g of XAD-7 resin at different temperatures for 5 min prior to voltammetric measurement. The effect of the mixing temperature of the sample with the resin on the voltammetric Cr(VI) signal in the presence of different surfactants was studied in the range from 20 to 60 °C. The proposed method of removing interference from surfactants by mixing the sample with the XAD-7 resin at 60 °C was used for the determination of trace amounts of Cr(VI) in river water containing non-ionic, anionic, cationic surfactants, and biosurfactants.
Enhanced Wettability and Adhesive Property of PTFE through Surface Modification with Fluorinated Compounds
Authors: Asrafali Shakila Parveen , Periyasamy Thirukumaran , Kim Seong-Cheol , Lee Jae-Woong
Published: June 2024

Polytetrafluoroethylene (PTFE) is prized for its unique properties in electrical applications, but its natural hydrophobicity poses challenges as it repels water and can cause electrical short circuits, shortening equipment lifespan. In this work, the mentioned issue has been tackled by using two different fluorinated compounds, such as perfluorooctanoic acid (PFOA)/perfluorooctanol (PFOL), along with plasma processing to enhance the surface hydrophilicity (water attraction) of PTFE. This method, demonstrated on Teflon membrane, quickly transformed their surfaces from hydrophobic to hydrophilic in less than 30 s. The treated films achieved a water contact angle saturation of around 80°, indicating a significant increase in water affinity. High-resolution C 1s X-ray photoelectron spectroscopy (XPS) confirmed the formation of new bonds, such as -COOH and -OH, on the surface, responsible for enhanced hydrophilicity. Extended plasma treatment led to further structural changes, evidenced by increased intensity in infrared (IR) and Raman spectra, particularly sensitive to vibrations associated with the C-F bond. Moreover, Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR) showed the formation of surface-linked functional groups, which contributed to the improved water attraction. These findings decisively show that treatment with fluoro-compound along with plasma processing can be considered as a highly effective and rapid method for converting PTFE surfaces from hydrophobic to hydrophilic, facilitating its broader use in various electrical applications.
Modern Electromagnetic-Radiation-Shielding Materials Made Using Different Knitting Techniques
Authors: Mikołajczyk Zbigniew , Nowak Iwona , Januszkiewicz Łukasz , Szewczyk Monika , Junak Joanna
Published: June 2024

This paper summarizes the possibility of employing knitted textile barriers as a shield against electromagnetic fields to protect the human body from their negative impact. Ten variants of knitted fabrics made of electrically conductive yarns, steel, and copper wire that differed in stitch pattern, structural parameters, and raw material, were designed, manufactured, and tested. The knitted fabrics produced differed in structural parameters, including course and wale density, surface density, thickness, thread length in the loop, wale and course take-up, volume cover factor, and surface porosity. These parameters were examined in accordance with the research methodology used in knitting. Barrier measurements were taken in the direction of the wales and in the direction of the courses for two frequencies of electromagnetic fields: 2–4 GHz and 4–7 GHz. It was observed that the shielding effectiveness of the manufactured materials depends on the structural parameters of the fabric, the stiches applied, and the type of yarn.
Tribological Properties of Composites Based on Single-Component Powdered Epoxy Matrix Filled with Graphite
Authors: Smoleń Jakub , Stępień Krzysztof , Mikuśkiewicz Marta , Myalska-Głowacka Hanna , Kozioł Mateusz , Godzierz Marcin , Janeczek Henryk , Czakiert Jan
Published: June 2024

Composites based on powdered single-component epoxy matrix are an alternative technological solution for composites produced using liquid epoxy resins. This article describes in detail the process of producing graphite-reinforced composites for tribological applications. The advantages and disadvantages of technological processes where the matrix is a single-component epoxy powder were demonstrated, and the properties of the obtained materials were examined. A series of composite materials with the graphite filler with sizes below 10 μm and below 45 μm and weight additions of 5, 10, 20, 30% were produced. Mechanical tests and tribological tests conducted with the pin-on-block method were performed, and the mechanism of tribological wear was described. The conducted research allowed us to conclude that the incorporation of graphite, regardless of particle size, above 10% by weight results in a significant reduction in the friction coefficient (approximately 40–50% lower than in unfilled epoxy resin), which is beneficial in the production of cheap self-lubricating materials.
The Effect of Nitriding Temperature of AISI 316L Steel on Sub-Zero Corrosion Resistance in C2H5OH
Authors: Kucharska Beata , Kamiński Janusz , Kulikowski Krzysztof , Borowski Tomasz , Sobiecki Jerzy Robert , Wierzchoń Tadeusz
Published: June 2024

In this paper, glow nitriding processes at cathode potential are used at various temperatures to investigate how they affect the corrosion resistance of 316L steel in ethanol at temperatures of 22 °C and −30 °C. Lowering the test temperature reduces the corrosion rate of the nitrided layers. Conversely, glow nitriding at 450 °C improves the corrosion resistance of the tested steel. Increasing the nitriding temperature to 520 °C increases the corrosion rate. It should be noted that the ethyl alcohol solution, due to the lack of aggressive ions, does not cause significant changes in the corrosion rate of the steel. The value of the corrosion current varies in the range of 10−2–10−3 µA/cm2. Nitrided layers increase the contact angle measured for water and are entirely wettable for ethanol. The objective of this study is to evaluate the effect of the nitriding temperature of AISI 316L steel on its corrosion resistance in an ethanol solution at room temperature and at −30 °C.
Study on the Tribological Properties of DIN 16MnCr5 Steel after Duplex Gas-Nitriding and Pack Boriding
Authors: Carrera Espinoza Rafael , Alvarez Vera Melvyn , Wettlaufer Marc , Kerl Manuel , Barth Stefan , Moreno Garibaldi Pablo , Díaz Guillen Juan Carlos , Hernández García Héctor Manuel , Muñoz Arroyo Rita , Ortega Javier A.
Published: June 2024

DIN 16MnCr5 is commonly used in mechanical engineering contact applications such as gears, joint parts, shafts, gear wheels, camshafts, bolts, pins, and cardan joints, among others. This study examined the microstructural and mechanical properties and tribological behavior of different surface treatments applied to DIN 16MnCr5 steel. The samples were hardened at 870 °C for 15 min and then quenched in water. The surface conditions evaluated were as follows: quenched and tempered DIN 16MnCr5 steel samples without surface treatments (control group), quenched and tempered DIN 16MnCr5 steel samples with gas-nitriding at 560 °C for 6 h, quenched and tempered DIN 16MnCr5 steel samples with pack boriding at 950 °C for 4 h, and quenched and tempered DIN 16MnCr5 steel samples with duplex gas-nitriding and pack boriding. Microstructure characterization was carried out using metallographic techniques, optical microscopy, scanning electron microscopy with energy-dispersive spectroscopy, and X-ray diffraction. The mechanical properties were assessed through microhardness and elastic modulus tests using nanoindentation. The tribological behavior was evaluated using pin-on-disc tests following the ASTM G99-17 standard procedure under dry sliding conditions. The results indicated that the surface treated with duplex gas-nitriding and pack boriding exhibited the highest wear resistance and a reduced coefficient of friction due to improved mechanical properties, leading to increased hardness and elastic modulus.
Development and Modification of New or Recycled Materials and Technological Processes towards Sustainable Development
Authors: Liptai Pavol
Published: June 2024

Quality and environmental sustainability are fundamental to the healthy and proper functioning of society on Earth [...]
Structure and Properties of Metastable β Ti–25Nb–8Sn Alloy following Cold Rolling and Aging Treatments
Authors: Hsu Hsueh-Chuan , Wu Shih-Ching , Jian Zhong-Lin , Ho Wen-Fu
Published: June 2024

Metal implants require an elastic modulus close to cortical bone (<30 GPa) to avoid stress shielding and ensure adequate load-bearing strength. The metastable β-type Ti–25Nb–8Sn alloy has a low elastic modulus (52 GPa), but its yield strength (<500 MPa) needs enhancement. This study enhances Ti–25Nb–8Sn’s elastic admissible strain through cold rolling and aging heat treatments, investigating the microstructure’s impact on mechanical and corrosion properties. The results show that lower-temperature aging (<450 °C) leads to ω-phase precipitation, yielding a 300% increase in yield strength (>1900 MPa). However, this also increases the elastic modulus (~80 GPa), limiting the deformation ability. Higher-temperature aging (>500 °C) eliminates the ω phase, transforming it into α precipitates, resulting in a lower elastic modulus (~65 GPa) and improved deformation ability, with substantial yield strength (>1000 MPa). In summary, the optimal process conditions are determined as 90% cold rolling followed by aging treatment at 550 °C. Under these conditions, Ti–25Nb–8Sn achieves the most suitable yield strength (1207 MPa) and high corrosion resistance, retaining a relatively low elastic modulus (64.7 GPa) and high elastic admissible strain (1.93%). This positions it as an ideal material for biomedical implants.
Reactive Infiltration: Effects of Different Parameters
Authors: López-González M. Karla , Figueroa-Quintero Leidy , Villalgordo-Hernández David , Ramos Fernández Enrique V. , Narciso Javier
Published: June 2024

Currently, the production of complex SiC and SiC/SiC parts through reactive infiltration is one of the most widely used technologies, due to its versatility and cost-effectiveness compared to more conventional technologies such as Hot Isostatic Pressing (HIP). This technology, while widely adopted, still faces some debate regarding the mechanisms of infiltration. Questions persist about what determines how infiltration occurs and whether the process is governed by physics (flow dynamics) or chemistry (reactions at the triple line (LT: (contact line between the solid, liquid and gas phases)). The present work provides new strong/consistent proof that reactive infiltration is mainly controlled by chemical reaction.
Parametric Modelling of the Crystalline Microstructure of the MCM41-Type Mesoporous Silica Modified with Derivatives of Alkyls
Authors: Stocki Jarosław , Kuśmierz Marcin , Sofińska-Chmiel Weronika , Stankevič Marek , Puchała Marcin , Kojdecki Marek A. , Gąska Robert , Grajek Henryk
Published: June 2024

A siliceous material in which a framework order was established with a surfactant with sixteen carbon atoms in alkyl chains, MCM-41-C16, was synthesised, surface-modified, and tested regarding the selected physical properties. The pristine material was extracted in an acidic aqueous alcohol and then lined with different surface groups. The properties of four adsorbents were investigated using XRD, X-ray photoelectron spectroscopy, and N2 physisorption techniques. The unit–cell constant was determined from X-ray diffractograms, being in fixed relation to the edge length of the hexagonal frame. The specific surface areas of mesopores and whole crystallites were determined from low-temperature N2-physisorption isotherms. The novelty of this work is a mathematical model of a crystalline microstructure explaining the sizes and shapes of crystalline grains in relation to adsorption features, proposed and successfully tested with the aforementioned experimental data. The roughness of the surface is different from one that is necessary to explain the experimental characteristics quantitatively.
The Microstructural Reconstruction of Variously Sintered Ni-SDC Cermets Using Focused Ion Beam Scanning Electron Microscopy Nanotomography
Authors: Kapun Gregor , Majorovits Endre , Šturm Sašo , Marinšek Marjan , Skalar Tina
Published: June 2024

This work focuses in-depth on the quantitative relationships between primary first-order microstructural parameters (i.e., volume fractions of various phases and particle size distribution) with the more complex second-order topological features (i.e., connectivity of phases, three-phase boundary length (TPBL), interfacial areas, or tortuosity). As a suitable model material, a cermet nickel/samaria-doped ceria (Ni-SDC) is used as an anode in a solid oxide fuel cell (SOFC). A microstructure description of nano-sized Ni-SDC cermets, fabricated at various sintering conditions from 1100 °C to 1400 °C, was performed using FIB-SEM nanotomography. The samples were serially sectioned employing a fully automated slicing procedure with active drift correction algorithms and an auto-focusing routine to obtain a series of low-loss BSE images. Advanced image processing algorithms were developed and applied directly to image data volume. The microstructural–topological relationships are crucial for the microstructure optimisation and, thus, the improvement of the corresponding electrode performance. Since all grains of individual phases (Ni, SDC, or pores) did not percolate, special attention was given to the visualisation of the so-called active TPBL. Based on the determined microstructure characteristics of the prepared Ni-SDC cermets, including simulations of gas flow and pressure drop, thermal treatment at 1200 °C was recognised as the most appropriate sintering temperature.
Implementation and Possibilities of Fuzzy Logic for Optimal Operation and Maintenance of Marine Diesel Engines
Authors: Gharib Hla , Kovács György
Published: June 2024

This paper explores the implementation and possibilities of utilizing fuzzy logic theory for optimal operation and early fault detection in marine diesel engines. It emphasizes its role in managing the complexity and ambiguity inherent in engine performance and preventive maintenance. Preventive maintenance is crucial for ensuring the reliability and longevity of marine diesel engines. Implementing fuzzy logic control (FLC) systems can enhance the preventive maintenance strategies for these engines, leading to reduced downtime, lower maintenance costs, and improved overall performance. Through a comprehensive literature review and analysis of a case study, this paper demonstrates the adaptability, effectiveness, and transformative potential of fuzzy logic systems. Focusing on applications such as engine speed control, performance improvements, and early fault detection, the paper highlights the implementation of fuzzy logic for enhanced predictive capabilities. The study aims to offer a flexible approach to engine management through fuzzy logic, laying the way for significant improvement in optimal marine diesel engine operation.
A Coordinated Mode Switch Control Strategy for a Two-Gear Power-Split Hybrid System
Authors: Sun Qinpeng , Li Xueliang , Liu Xinlei , Wu Wei
Published: June 2024

The hybrid system can extend the range of special vehicles and meet the electrical requirements of on-board equipment. In this paper, the driving force plummet problem of a new two-gear power-split hybrid system was studied during gear switches in a hybrid mode. The dynamic model of a hybrid electric system was established, and the effects of the engine angular acceleration and angular jerk on vehicle power and ride performance were obtained. The optimal ratio of the torque change rate of the motor and engine in the mode switch process was proposed. Considering the battery limitation and the external characteristics of the engine, the method of determining the target speed of the engine during shifting was proposed. Considering the response characteristics of each power source, the dynamic coordinated control strategy of multiple power sources in the mode switch process was proposed. The vehicle dynamics model was established based on the Matlab/Simulink 2020b and verified by simulation and a hardware-in-the-loop (HIL) test. The results show that the dynamic coordinated control strategy can reduce the peak impact by 80.33%, effectively improve the vehicle power and ride performance, and prevent the occurrence of high-current battery charging.