bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Environmental Factors Affecting the Quality of Neopyropia yezoensis Cultivated in the Yellow Sea
Authors: Huang Danlin , Sun Zhenjie , Wang Lijun , Feng Zezhong , Niu Jianfeng , Ye Qing , Wang Guangce
Published: February 2023

To investigate the potential influences of nutrients and solar irradiance of the sea area on the laver industry, Neopyropia yezoensis samples and the corresponding surface water were collected at different sites in Haizhou Bay and the Jimo aquafarm, and the solar irradiance was recorded on-site. Then the cellular compositions and the nutrients of seawater were determined. A comparative experiment was also designed to investigate the effect of strong light on the cellular composition of N. yezoensis. Gray correlation analysis showed that the seawater nutrient levels and solar irradiance had a similar correlation degree of 0.6 to 0.8, which indicated similar effects on algal cellular composition. Compared with those samples collected from Haizhou Bay, the algae cultivated at the Jimo aquafarm had higher contents of total protein and hydrolyzable polysaccharides. In addition, the content of chlorophyll a was relatively lower and that of β-carotene higher in the early-stage samples. The results of the comparative experiment showed that the decrease in light intensity on algae promoted the synthesis of chlorophyll a and R-phycoerythrin. It is speculated that the nutrient deficiency in the seawater and the resulting high transparency of the water make the algae more exposed to strong light conditions. This may be the reason for the poor glossiness and hardness of the laver products made from the cultivated algae in the north Yellow Sea. Thus, it puts forward specific requirements for the modification of N. yezoensis cultivation techniques in the north Yellow Sea.
A Survey on Model-Based Control and Guidance Principles for Autonomous Marine Vehicles
Authors: Degorre Loïck , Delaleau Emmanuel , Chocron Olivier
Published: February 2023

With the increasing number of applications for both surface and underwater autonomous vehicles, a great amount of control methods and guidance principles has been developed over the years. This work proposes a review of the most common of these methods. It is mainly focused on model-based nonlinear control methods and guidance principles. Notably, this work details examples and variations of model-based linearizing controllers, applications of line of sight guidance, sliding mode controllers and several other less common control methods for both fully-actuated and underactuated vehicles. Additionally, this work proposes an alternative definition of underactuation with respect to the task allowing for a better understanding of the consequences of underactuation on control. Comparison of fully-actuated and underactuated cases shows how control laws can be used to solve the problems of underactuation and what mechanisms can be used to compensate for the lack of actuation on a degree of freedom. The reviewed methods are compared and discussed with respect to their capabilities, limitations and suitability for typical tasks.
Life-Cycle Cost Assessment Using the Power Spectral Density Function in a Coastal Concrete Bridge
Authors: Hadizadeh-Bazaz Mehrdad , Navarro Ignacio J. , Yepes Víctor
Published: February 2023

Recently, the repair and maintenance of structures has been necessary to prevent these structures’ sudden collapse and to prevent human and financial damage. A natural factor in marine environments that destroys structures and reduces their life is the presence of chloride ions. So regular health monitoring of concrete coastal buildings for on-time repair is essential. This study investigates the performance of the power spectral density (PSD) method as a non-destructive damage-detection method to monitor the location and amount of damage caused by chloride ions during a structure’s life using different approaches according to life-cycle assessment (LCA) and life-cycle cost assessment (LCCA). In this regard, chloride corrosion damage dependent on zone distance from seawater was first calculated to obtain the service life of each part of a coastal concrete bridge according to the conventional method. Based on rebar corrosion each year, the next stage forecasted the bridge’s concrete deterioration. The PSD method monitored the annual loss of reinforcement cross-sectional area, changes in dynamic characteristics such as stiffness and mass, and the bridge structure’s life using sensitivity equations and the linear-least-squares algorithm. Finally, according to the location and quality of damage in each year of bridge life until the end of life, LCC and maintenance and repair costs of the PSD method were compared with the conventional method. The results showed that this strategy was very effective at lowering and optimizing the costs of maintenance and repair caused by chloride corrosion.
Reducing Ship’s Energy Consumption through Accommodation and Cargo Spaces Lights Automation
Authors: Dimitranov Dilyan , Belev Blagovest
Published: February 2023

The effective use of energy proposes using less energy to achieve the same goal. The International Maritime Organization started using criteria for ship’s energy efficiency in 2013, when the new International Convention for the Prevention of Pollution from Ships, Annex VI, was adopted. The purpose of the Annex is to improve the ships’ energy efficiency through the use of new technologies such as improved hull design, and new propulsion systems, including innovations in energy management. One of the topics for improving the car carriers’ energy efficiency is the constantly working lights in the superstructure and on the car decks. Lights’ energy consumption may be negligible on most ships, but on car carriers, the consumption is of greater magnitude. This article presents a survey of the improvement of energy consumption on board a car carrier during regular voyages as well as the cost-effectiveness of introducing light control automation. The authors of this article review an example of light automation set up to control the lights in a ship’s superstructure and on the car decks. The implementation of such a system and the different types of automation are also reviewed. This research is towards new regulations, established by Maritime Environment Protection Committee and implemented in shipping since 1 November 2022. Conclusions for practical use are extracted.
Co-Application of Silver Nanoparticles and Symbiotic Fungus Piriformospora indica Improves Secondary Metabolite Production in Black Rice
Authors: Solanki Shikha , Lakshmi G. B. V. S. , Dhiman Tarun , Gupta Samta , Solanki Pratima R. , Kapoor Rupam , Varma Ajit
Published: February 2023

In the current research, unique Nano-Embedded Fungus (NEF), made by the synergic association of silver nanoparticles (AgNPs) and endophytic fungus (Piriformospora indica), is studied, and the impact of NEF on black rice secondary metabolites is reported. AgNPs were synthesized by chemical reduction process using the temperature-dependent method and characterized for morphological and structural features through UV visible absorption spectroscopy, zeta potential, XRD, SEM-EDX, and FTIR spectroscopy. The NEF, prepared by optimizing the AgNPs concentration (300 ppm) in agar and broth media, showed better fungal biomass, colony diameter, spore count, and spore size than the control P. indica. Treatment with AgNPs, P. indica, and NEF resulted in growth enhancement in black rice. NEF and AgNPs stimulated the production of secondary metabolites in its leaves. The concentrations of chlorophyll, carotenoids, flavonoids, and terpenoids were increased in plants inoculated with P. indica and AgNPs. The findings of the study highlight the synergistic effect of AgNPs and the fungal symbionts in augmenting the secondary metabolites in leaves of black rice.
Polyketides as Secondary Metabolites from the Genus Aspergillus
Authors: Bai Xuelian , Sheng Yue , Tang Zhenxing , Pan Jingyi , Wang Shigui , Tang Bin , Zhou Ting , Shi Lu’e , Zhang Huawei
Published: February 2023

Polyketides are an important class of structurally diverse natural products derived from a precursor molecule consisting of a chain of alternating ketone and methylene groups. These compounds have attracted the worldwide attention of pharmaceutical researchers since they are endowed with a wide array of biological properties. As one of the most common filamentous fungi in nature, Aspergillus spp. is well known as an excellent producer of polyketide compounds with therapeutic potential. By extensive literature search and data analysis, this review comprehensively summarizes Aspergillus-derived polyketides for the first time, regarding their occurrences, chemical structures and bioactivities as well as biosynthetic logics.
Genotypic Analysis of the Population Structure in Malassezia globosa and Malassezia restricta
Authors: Hadrich Ines , Khemakhem Nahed , Ilahi Amin , Trabelsi Houaida , Sellami Hayet , Makni Fattouma , Neji Sourour , Ayadi Ali
Published: February 2023

The molecular characterization of Malassezia spp. isolates from animals and humans has not been thoroughly studied. Although a range of molecular methods has been developed for diagnosing Malassezia species, they have several drawbacks, such as inefficiency in differentiating all the species, high cost and questionable reproducibility. The present study aimed to develop VNTR markers for genotyping Malassezia isolated from clinical and animal samples. A total of 44 M. globosa and 24 M. restricta isolates were analyzed. Twelve VNTR markers were selected on seven different chromosomes (I, II, III, IV, V, VII and IX), six for each Malassezia species. The highest discriminatory power for a single locus was obtained with the STR-MG1 marker (0.829) and STR-MR2 marker (0.818) for M. globosa and M. restricta, respectively. After the analysis of multiple loci, 24 genotypes were noted among 44 isolates in M. globosa, with a discrimination index D of 0.943 and 15 genotypes were noted among 24 isolates in M. restricta, with a discrimination index D of 0.967. An endogenous infection was detected in two patients. Different genotypes of M. globosa strains colonized one patient. Interestingly, VNTR markers analysis revealed a carriage between a breeder and his dog in three cases for M. globosa and two for M. restricta. The FST (0.018 to 0.057) values indicate a low differentiation between the three populations of M. globosa. These results suggest a dominant clonal mode of reproduction in M. globosa. The typing of M. restricta showed a genotypic diversity of the strains, which can cause various skin pathologies. However, patient five was colonized with strains having the same genotype collected from different body parts (back, shoulder). VNTR analysis was capable of identifying species with high accuracy and reliability. More importantly, the method would facilitate monitoring Malassezia colonization in domestic animals and humans. It was shown that the patterns are stable and the method is discriminant, making it a powerful tool for epidemiological purposes.
Renewing Lost Genetic Variability with a Classical Yeast Genetics Approach
Authors: Gupte Ameya Pankaj , Pierantoni Debora Casagrande , Conti Angela , Donati Leonardo , Basaglia Marina , Casella Sergio , Favaro Lorenzo , Corte Laura , Cardinali Gianluigi
Published: February 2023

Due to their long domestication time course, many industrial Saccharomyces cerevisiae strains are adopted in numerous processes mostly for historical reasons instead of scientific and technological needs. As such, there is still significant room for improvement for industrial yeast strains relying on yeast biodiversity. This paper strives to regenerate biodiversity with the innovative application of classic genetic methods to already available yeast strains. Extensive sporulation was indeed applied to three different yeast strains, specifically selected for their different origins as well as backgrounds, with the aim of clarifying how new variability was generated. A novel and easy method to obtain mono-spore colonies was specifically developed, and, to reveal the extent of the generated variability, no selection after sporulation was introduced. The obtained progenies were then tested for their growth in defined mediums with high stressor levels. A considerable and strain-specific increase in both phenotypic and metabolomic variability was assessed, and a few mono-spore colonies were found to be of great interest for their future exploitation in selected industrial processes.
Association of Oral Health with Risk of Rheumatoid Arthritis: A Nationwide Cohort Study
Authors: Chang Yoonkyung , Chung Min Kyung , Park Jung-Hyun , Song Tae-Jin
Published: February 2023

Periodontitis and rheumatoid arthritis (RA) are inflammatory diseases that share many similarities. We aimed to investigate the associations of periodontitis and oral hygiene status and behaviors with RA in a nationwide general population cohort. Participants from the National Health Screening cohort database of Korea who underwent oral health screening by dentists between 2003 and 2004 were included. The occurrence of RA was analyzed according to the presence of periodontitis, oral health examination findings, and behaviors. Overall, 2,239,586 participants were included. During a median of 16.7 years, RA occurred in 27,029 (1.2%) participants. The risk for incident RA was higher when participants had periodontitis (hazard ratio (HR) 1.2, 95% confidence interval (CI), 1.08−1.24) and an increased number of missing teeth (HR 1.5, 95% CI, 1.38−1.69). In contrast, better oral hygiene behaviors, such as a higher frequency of daily tooth brushing (HR 0.76, 95% CI 0.73–0.79, p for trend <0.001) and a recent history of dental scaling (HR 0.96, 95% CI 0.94–0.99), were associated with a lower occurrence of RA. Periodontitis and increased missing teeth were associated with an increased risk of RA. Maintaining good oral hygiene through frequent tooth brushing and regular dental scaling may reduce the risk of RA occurrence.
Performance of US and European Exchange Traded Funds: A Base Point-Slack-Based Measure Approach
Authors: Henriques Carla O. , Neves Maria E. , Conceição Jeremias A. , Vieira Elisabete S.
Published: February 2023

This study evaluates the performance of United States (US) and European Exchange Traded Funds (ETFs) using the non-oriented version of the base point-slack-based measure (BP-SBM) Data Envelopment Analysis (DEA) model, which allows for handling negative data that can arise in some of the metrics traditionally used in this type of analysis. Our findings show that US efficient ETFs are considered benchmarks more often than European efficient ETFs. Nonetheless, it was possible to conclude that European inefficient ETFs were generally less inefficient than US ETFs. Our findings also show that ETFs’ efficiency (particularly for US ETFs) in the short run is more related to risk than to profitability factors. This implies that as the time horizon lengthens, the importance of profitability factors for the ETFs’ financial performance grows.
Protected Areas in the Function of Sustainable Tourism Development—A Case of Deliblato Sands Special Nature Reserve, Vojvodina Province
Authors: Trišić Igor , Privitera Donatella , Ristić Vladica , Štetić Snežana , Milojković Danka , Maksin Marija
Published: February 2023

The Deliblato Sands Special Nature Reserve (SNR) is located in the Autonomous Province of Vojvodina (Northern Serbia). The favorable position implies the proximity to large cities with which it has good traffic connections. Romania, Hungary, Bulgaria, Croatia, and other countries from the region represent a dispersive zone. The topic of this paper is the function that the SNR has in sustainable tourism development. The objective of this work is the analytical research of the available written data, as well as those obtained after the conducted survey. The basis of the research is to find out how and to what extent the SNR contributes to sustainable tourism development. The research was carried out by measuring the value of sustainable tourism indicators, and examining the attitudes of residents, visitors, and students about the current state of sustainable tourism and the importance of the SNR for future tourism development. Respondents were selected using a random sample method. The authors used qualitative and quantitative methodologies in the paper. This research examined the SNR sustainable development by measuring sustainability indicators and surveying 1884 respondents (714 residents, 620 visitors, and 550 students) about sustainable tourism in the SNR. The obtained data were analyzed and presented with the help of SPSS v. 21 software. The research results can be used to create national and international strategies for sustainable tourism development.
Assessing the Relative and Combined Effects of Network, Demographic, and Suitability Patterns on Retail Store Sales
Authors: Wang Junyi , Robinson Derek T.
Published: February 2023

Despite challenges associated with acquiring proprietary sales data, there exists a wealth of literature using different types of data (e.g., spending, demographic, geographic) to understand or represent different drivers of retail store sales. We contribute to the spatial analysis of drivers of retail store sales by analyzing the relative influence of road networks, demographic, and suitability variables on retail store sales within the home-improvement sector. Results demonstrate that the inclusion of variables describing the road network pattern is more influential in predicting store sales than demographic and suitability variables with linear models (e.g., ordinary- and partial-least squares regression) as well as with a non-linear mathematical model derived using artificial intelligence. The analysis builds on previous research estimating consumer spending and a big-data suitability analysis for site selection that incorporates spatial interaction models, location quotient, and other unique criteria that are typically used in isolation. The overarching contribution of our results is the demonstration that network patterns can play a critical role in retail store sales, especially when regressions, analogs, and other simple methods for site selection are used.
Digital Mapping of Soil Properties Using Ensemble Machine Learning Approaches in an Agricultural Lowland Area of Lombardy, Italy
Authors: Adeniyi Odunayo David , Brenning Alexander , Bernini Alice , Brenna Stefano , Maerker Michael
Published: February 2023

Sustainable agricultural landscape management needs reliable and accurate soil maps and updated geospatial soil information. Recently, machine learning (ML) models have commonly been used in digital soil mapping, together with limited data, for various types of landscapes. In this study, we tested linear and nonlinear ML models in predicting and mapping soil properties in an agricultural lowland landscape of Lombardy region, Italy. We further evaluated the ability of an ensemble learning model, based on a stacking approach, to predict the spatial variation of soil properties, such as sand, silt, and clay contents, soil organic carbon content, pH, and topsoil depth. Therefore, we combined the predictions of the base learners (ML models) with two meta-learners. Prediction accuracies were assessed using a nested cross-validation procedure. Nonetheless, the nonlinear single models generally performed well, with RF having the best results; the stacking models did not outperform all the individual base learners. The most important topographic predictors of the soil properties were vertical distance to channel network and channel network base level. The results yield valuable information for sustainable land use in an area with a particular soil water cycle, as well as for future climate and socioeconomic changes influencing water content, soil pollution dynamics, and food security.
Extraction of Urban Built-Up Areas Using Nighttime Light (NTL) and Multi-Source Data: A Case Study in Dalian City, China
Authors: Li Xueming , Song Yishan , Liu He , Hou Xinyu
Published: February 2023

The rapid urban development associated with China’s reform and opening up has been the source of many urban problems. To understand these issues, it is necessary to have a deep understanding of the distribution of urban spatial structure. Taking the six districts of Dalian as an example, in this study, we integrated the enhanced vegetation index, points of interest, and surface temperature data into night light data. Furthermore, herein, we analyze the kernel density of the points of interest and construct three indices using image geometric mean: a human settlement index (HSI), a HSI-POI (HP) index, and a HSI-POI-LST (HPL) index. Using a support vector machine to identify the land type in Dalian’s built-up area, 1000 sampling points were created for verification. Then, the threshold boundary corresponding to the highest overall accuracy of each index and kappa coefficient was selected. The relevant conclusions are as follows: As compared with the other three types of data, the HPL index constructed in this study exhibited natural and social attributes, and the built-up area extracted using this method had the highest accuracy, a high image spatial resolution, and was able to overcome the omission issues observed when using one or two data sources. In addition, this method produces richer spatial details of the actual built-up area and provides more choices for assessing small-scale urban built-up areas in future research.
Teacher Beliefs and Practices of Language Assessment in the Context of English as a Lingua Franca (ELF): Insights from a CPD Course
Authors: Tsagari Dina , Reed Kirstin , Lopriore Lucilla
Published: February 2023

English as a lingua franca (ELF) has challenged English language teaching and learning and has recently impacted teacher education as well as teacher beliefs and practices. Nevertheless, there are very few studies exploring teachers’ beliefs and practices towards ELF-aware assessment. Within the framework of an online ERASMUS+ course, the current study investigated the perceptions of English language teachers towards assessment within two multilingual contexts, Norway and Italy. The data were collected through the assessment course activities and final assignments. The findings showed that most teachers were in agreement with balancing ELF-aware teaching and assessment but struggled to address formative and summative assessment mandates in their multilingual contexts. The evolving classroom context that characterizes multilingual settings demands teachers to develop flexibility and innovation as part of their language assessment literacy trajectories. This study has several implications for language teachers, teacher trainers, and future researchers.
Self-Similar Patterns from Abiotic Decarboxylation Metabolism through Chemically Oscillating Reactions: A Prebiotic Model for the Origin of Life
Authors: Papineau Dominic , Devine Kevin , Nogueira Bernardo Albuquerque
Published: February 2023

The origin of life must have included an abiotic stage of carbon redox reactions that involved electron transport chains and the production of lifelike patterns. Chemically oscillating reactions (COR) are abiotic, spontaneous, out-of-equilibrium, and redox reactions that involve the decarboxylation of carboxylic acids with strong oxidants and strong acids to produce CO2 and characteristic self-similar patterns. Those patterns have circular concentricity, radial geometries, characteristic circular twins, colour gradients, cavity structures, and branching to parallel alignment. We propose that COR played a role during the prebiotic cycling of carboxylic acids, furthering the new model for geology where COR can also explain the patterns of diagenetic spheroids in sediments. The patterns of COR in Petri dishes are first considered and compared to those observed in some eukaryotic lifeforms. The molecular structures and functions of reactants in COR are then compared to key biological metabolic processes. We conclude that the newly recognised similarities in compositions and patterns warrant future research to better investigate the role of halogens in biochemistry; COR in life-forms, including in humans; and the COR-stage of prebiotic carbon cycling on other planets, such as Mars.
Microbiome in Lower Urinary Tract Symptoms (LUTSs): Mapping the State of the Art with Bibliometric Analysis
Authors: Mostafaei Hadi , Salehi-Pourmehr Hanieh , Rahnama’i Mohammad Sajjad , Mostafaei Helia , Shariat Shahrokh F. , Hajebrahimi Sakineh
Published: February 2023

Background: The main objective of this study is to provide the first characterization of the current research field of the clinical microbiome in LUTSs. Methods: First-of-its-kind scientometric insight into the historical development and structural state of the discipline is provided by a field analysis, mapping, and sub-analysis of articles for future research. On 22 December 2022, the entire Scopus database was searched without language or date restrictions. Search terms included “Chronic prostatitis”, OR “Interstitial cystitis”, OR “Lower urinary tract symptoms”, OR “Lower urinary tract dysfunction”, OR “Overactive bladder”, OR “Incontinence”, OR “Urolithiasis”, OR “Urothelium”, OR “Urine”, OR “Urology”, OR “urinary disorder”, OR “Pathophysiology”, OR “Benign prostatic hyperplasia”, OR “Benign prostatic enlargement”, AND “Microbiota”, OR “Microbiome”, OR “Urobio-ma”, OR “Urobiota; microflora”. The author and institutional data were transformed using the analytical tool Biblioshiny (a Shiny app for Bibliometrix), which took into account variations in author spelling as well as institutional naming and subgroups. Results: The specified search strategy was able to locate 529 documents from 267 sources published from 1981 to 2022. The average number of years from publication was 4.59 years. The authors with the most publications were Wolfe AJ and Brubaker I. The top three most collaborative networks were Loyola University Chicago, Loyola University Medical Center, and the University of California San Diego. The most frequently occurring words among the 50 nodes were: human, humans, nonhuman, female, adult, article, microbiology, microflora, microbiota, and controlled study. Frontiers in Cellular and Infection Microbiology and the International Urogynecology Journal, followed by Nature Reviews Urology, were the top three most relevant sources in microbiome research in urology. Conclusions: One of the most crucial requirements for developing research policies and anticipating the scientific requirements of researchers is paying attention to the evolution of various scientific fields. Understanding research gaps and future needs in microbiome research in urology can be effectively understood by paying attention to the models, maps, and visualizations used in this research, which are the results of systematic analysis of scientific products in the most esteemed scientific journals in the world.
The Mitochondrial tRNASer(UCN) Gene: A Novel m.7484A>G Mutation Associated with Mitochondrial Encephalomyopathy and Literature Review
Authors: Borgione Eugenia , Lo Giudice Mariangela , Santa Paola Sandro , Giuliano Marika , Di Blasi Francesco Domenico , Di Stefano Vincenzo , Lupica Antonino , Brighina Filippo , Pettinato Rosa , Romano Corrado , Scuderi Carmela
Published: February 2023

Mitochondrial tRNASer(UCN) is considered a hot-spot for non-syndromic and aminoglycoside-induced hearing loss. However, many patients have been described with more extensive neurological diseases, mainly including epilepsy, myoclonus, ataxia, and myopathy. We describe a novel homoplasmic m.7484A>G mutation in the tRNASer(UCN) gene affecting the third base of the anticodon triplet in a girl with profound intellectual disability, spastic tetraplegia, sensorineural hearing loss, a clinical history of epilepsia partialis continua and vomiting, typical of MELAS syndrome, leading to a myoclonic epilepticus status, and myopathy with severe COX deficiency at muscle biopsy. The mutation was also found in the homoplasmic condition in the mother who presented with mild cognitive deficit, cerebellar ataxia, myoclonic epilepsy, sensorineural hearing loss and myopathy with COX deficient ragged-red fibers consistent with MERRF syndrome. This is the first anticodon mutation in the tRNASer(UCN) and the second homoplasmic mutation in the anticodon triplet reported to date.
Effect of Cu-Doped Carbon Quantum Dot Dispersion Liquid on the Lubrication Performance of Polyethylene Glycol
Authors: Liu Shusheng , Yu Xiuqian , Hu Enzhu , Su Enhao , Chen Yanjie , Wang Jianping , Hu Kunhong , Xu Yong , Hu Xianguo , Zhong Hua
Published: February 2023

Energy saving and reduced consumption of key materials such as bearings in high-end equipment can be realized by synthesizing a new lubricating functional additive, copper-doped carbon quantum dot dispersion liquid (Cu-CQDs) via hydrothermal reaction with glycerol, cupric chloride dihydrate, and choline chloride as raw materials. The influence of the dispersion liquid containing Cu-CQDs nanoparticles on the lubricating properties of polyethylene glycol (PEG200) was investigated on a four-ball friction tester. The wear scars of steel balls after friction were analyzed using a scanning electron microscope accompanied by energy dispersive spectroscopy (SEM/EDS), photoelectron microscopy, and Raman spectroscopy. The results revealed the friction and wear mechanism of Cu-CQDs. Cu-CQDs dispersion liquid can significantly enhance the lubrication performance of PEG. The average friction coefficient of PEG containing 2.0 wt% Cu-CQDs dispersion liquid was 40.99% lower than that of pure PEG. The friction and wear mechanism can be ascribed to friction, inducing Cu-CQDs to participate in the formation of boundary lubricating film, resulting in a low friction coefficient and wear scar diameter.
The Impact of TPA Auxiliary Donor and the π-Linkers on the Performance of Newly Designed Dye-Sensitized Solar Cells: Computational Investigation
Authors: Bouzzine Si Mohamed , Abdelaaziz Alioui , Hamidi Mohamed , Al-Zahrani Fatimah A. M. , Zayed Mohie E. M. , El-Shishtawy Reda M.
Published: February 2023

The efficiency of the newly designed dye-sensitized solar cells (DSSCs) containing triphenylamine, diphenylamine (TPA), phenothiazine, and phenoxazine as donors and triazine, phenyl with D1-D2-π-linker-π-(A)2 architecture has been investigated using density functional theory (DFT) and time-dependent (TD-DFT) methods. These methods were used to investigate the geometrical structures, electronic properties, absorption, photovoltaic properties, and chemical reactivity. Furthermore, the calculated results indicate that different architectures can modify the energy levels of HOMO and LUMO and reduce the energy gap. The absorption undergoes a redshift displacement. This work aims at calculating the structural geometries and the electronic and optical properties of the designed dyes. Furthermore, the dye adsorption characteristics, such as the optoelectronic properties and the adsorption energies in the TiO2 clusters, were calculated with counterpoise correction and discussed.
Microstructural Evolution and Mechanical Performance of Two Joints of Medium-Mn Stainless Steel with Low- and High-Alloyed Steels
Authors: Khedr Mahmoud , Ibrahim I. Reda , Jaskari Matias , Ali Mohammed , Abdel-Aleem Hamed A. , Mahmoud Tamer S. , Hamada Atef
Published: February 2023

In this work, 2 mm thick medium-Mn austenitic stainless steel (MMn–SS) plates were joined with austenitic NiCr stainless steel (NiCr–SS) and low-carbon steel (LCS) using the gas tungsten arc welding technique. A precise adjustment of the welding process parameters was conducted to achieve high-quality dissimilar joints of MMn–SS with NiCr–SS and LCS. The microstructural evolution was studied using laser scanning confocal and electron microscopes. Secondary electron imaging and electron backscatter diffraction (EBSD) techniques were intensively employed to analyze the fine features of the weld structures. The mechanical properties of the joints were evaluated by uniaxial tensile tests and micro-indentation hardness (HIT). The microstructure of the fusion zone (FZ) in the MMn–SS joints exhibited an austenitic matrix with a small fraction of δ-ferrite, ~6%. The tensile strength (TS) of the MMn–SS/NiCr–SS joint is significantly higher than that of the MMn–SS/LCS joint. For instance, the TSs of MMn–SS joints with NiCr–SS and LCS are 610 and 340 MPa, respectively. The tensile properties of MMn–SS/LCS joints are similar to those of BM LCS, since the deformation behavior and shape of the tensile flow curve for that joint are comparable with the flow curve of LCS. The HIT measurements show that the MMn–SS/NiCr–SS joint is significantly stronger than the MMn–SS/LCS joint since the HIT values are 2.18 and 1.85 GPa, respectively.
Dynamic Stability of Nanobeams Based on the Reddy’s Beam Theory
Authors: Huang Youqin , Huang Richeng , Zhang Jiachang
Published: February 2023

The dynamic stability of nanobeams has been investigated by the Euler-Bernoulli and Timoshenko beam theories in the literature, but the higher-order Reddy beam theory has not been applied in the dynamic stability evaluation of nanobeams. In this work, the governing equations of the motion and dynamic stability of a nanobeam embedded in elastic medium are derived based on the nonlocal theory and the Reddy’s beam theory. The parametric studies indicate that the principal instability region (PIR) moves to a lower frequency zone when length, sectional height, nonlocal parameter, Young’s modulus and mass density of the Reddy nanobeam increase. The PIR shifts to a higher frequency zone only under increasing shear modulus. Increase in length makes the width of the PIR shrink obviously, while increase in height and Young’s modulus makes the width of the PIR enlarge. The sectional width and foundation modulus have few effects on PIR.
Porous Polymer Materials for CO2 Capture and Electrocatalytic Reduction
Authors: Wang Hui , Wang Genyuan , Hu Liang , Ge Bingcheng , Yu Xiaoliang , Deng Jiaojiao
Published: February 2023

Efficient capture of CO2 and its conversion into other high value-added compounds by electrochemical methods is an effective way to reduce excess CO2 in the atmosphere. Porous polymeric materials hold great promise for selective adsorption and electrocatalytic reduction of CO2 due to their high specific surface area, tunable porosity, structural diversity, and chemical stability. Here, we review recent research advances in this field, including design of porous organic polymers (POPs), porous coordination polymers (PCPs), covalent organic frameworks (COFs), and functional nitrogen-containing polymers for capture and electrocatalytic reduction of CO2. In addition, key issues and prospects for the optimal design of porous polymers for future development are elucidated. This review is expected to shed new light on the development of advanced porous polymer electrocatalysts for efficient CO2 reduction.
Variation in Juvenile Long Bone Properties as a Function of Age: Mechanical and Compositional Characterization
Authors: Vázquez Sanz Claudia , Victoria Rodríguez Ignacio , Forriol Francisco , Tejado Elena , Lopez-Valdes Francisco J.
Published: February 2023

Bone is a heterogeneous, hierarchical biocomposite material made of an organic matrix filled with a mineral component, which plays an important role in bone strength. Although the effect of the mineral/matrix ratio on the mechanical properties of bone during aging has been intensively investigated, the relationship between the mechanical properties and the chemical composition of bone with age requires additional research in juvenile individuals. In this study, bone coupons from bovine and ovine animal species were machined from cortical areas of long bones to quantify whether the variation in mechanical properties at different stages of development is related to the change in the composition of bone tissue. An energy-dispersive X-ray detector (EDX) attached to a scanning electron microscope (SEM) was used to perform a compositional analysis of the tissue. In addition, nanoindentation analyses were carried out to address how the elastic modulus changed with age. Nonparametric statistical analyses found significant differences (p < 0.05) in Ca content and elastic modulus between species, but no differences were found within each species with development. A multiple linear regression model found that the elastic modulus was significantly related to the decrease in P and C in the samples, to the animal species (larger in bovine), and development, although not linearly. This model also found an interaction between Ca and development that could explain the lack of significance of the relationship between the elastic modulus and development in the univariate models.
Minimizing the Main Strains and Thickness Reduction in the Single Point Incremental Forming Process of Polyamide and High-Density Polyethylene Sheets
Authors: Rosca Nicolae , Oleksik Mihaela , Rosca Liviu , Avrigean Eugen , Trzepieciński Tomasz , Najm Sherwan Mohammed , Oleksik Valentin
Published: February 2023

Polymeric materials are increasingly used in the automotive industry, aeronautics, medical device industry, etc. due to their advantage of providing good mechanical strength at low weight. The incremental forming process for polymeric materials is gaining increasing importance because of the advantages it offers: relatively complex parts can be produced at minimum cost without the need for complex and expensive dies. Knowing the main strains and especially the thickness reduction is particularly important as it directly contributes to the mechanical strength of the processed parts, including in operation. For the design of experiments, the Taguchi method was chosen, with an L18 orthogonal array obtained by varying the material on two levels (polyamide and polyethylene) and the other three parameters on three levels: punch diameter (6 mm, 8 mm and 10 mm), wall angle (50°, 55° and 60°) and step down (0.5 mm, 0.75 mm and 1 mm). The output parameters were strain in the x direction, strain in the y direction, major strain, minor strain, shear angle and thickness reduction. Two analyses were conducted: signal-to-noise ratio analysis with the smaller-is-better condition and analysis of variance. The optimum values for which the thickness was reduced were the following: wall angle of 50°, punch diameter of 10 mm and step down of 0.75 mm.
Forming Limit Analysis of Thin-Walled Extruded Aluminum Alloy Tubes under Nonlinear Loading Paths Using an Improved M-K Model
Authors: Zhu Haihui , Lin Yanli , Chen Kelin , He Zhubin
Published: February 2023

To meet the requirement of lighter weight and better performance in tube hydroforming, one of the most important tasks is to accurately predict the forming limit of thin-walled tubes under nonlinear loading paths. This work established the M-K+DF2012 model, a combination of the M-K model and the DF2012 ductile fracture criterion, for the forming limit prediction of thin-walled tubes under nonlinear loading paths. In this model, the failure of the groove is determined by the DF2012 criterion, and the corresponding strains in the uniform region are the limit strains. The limit strains of an AA6061 aluminum alloy tube under a set of linear loading paths and two typical nonlinear loading paths were tested. Parameter values of the M-K+DF2012 model for the tube were determined based on the experimental limit strains under linear loading paths, and the limit strains under the two nonlinear loading paths were predicted. Then the strain-based forming limit diagram (ε-FLD) and the polar effective plastic strain FLD (PEPS-FLD) of the tube under different pre-strains were predicted and discussed. The results show that the limit strains of the tube are obviously path-dependent, and the M-K+DF2012 model can reasonably capture the limit strains of the tube under both linear and nonlinear loading paths. The predicted ε-FLD shows a strong dependence on the pre-strain, while the predicted PEPS-FLD is weakly strain path-dependent and almost path-independent on the right-hand side for the AA6061 tube.
Correlation-Driven Topological Transition in Janus Two-Dimensional Vanadates
Authors: Hussain Ghulam , Fakhredine Amar , Islam Rajibul , Sattigeri Raghottam M. , Autieri Carmine , Cuono Giuseppe
Published: February 2023

The appearance of intrinsic ferromagnetism in 2D materials opens the possibility of investigating the interplay between magnetism and topology. The magnetic anisotropy energy (MAE) describing the easy axis for magnetization in a particular direction is an important yardstick for nanoscale applications. Here, the first-principles approach is used to investigate the electronic band structures, the strain dependence of MAE in pristine VSi2Z4 (Z = P, As) and its Janus phase VSiGeP2As2 and the evolution of the topology as a function of the Coulomb interaction. In the Janus phase the compound presents a breaking of the mirror symmetry, which is equivalent to having an electric field, and the system can be piezoelectric. It is revealed that all three monolayers exhibit ferromagnetic ground state ordering, which is robust even under biaxial strains. A large value of coupling J is obtained, and this, together with the magnetocrystalline anisotropy, will produce a large critical temperature. We found an out-of-plane (in-plane) magnetization for VSi2P4 (VSi2As4), and an in-plane magnetization for VSiGeP2As2. Furthermore, we observed a correlation-driven topological transition in the Janus VSiGeP2As2. Our analysis of these emerging pristine and Janus-phased magnetic semiconductors opens prospects for studying the interplay between magnetism and topology in two-dimensional materials.
Effect of Titanium and Molybdenum Cover on the Surface Restructuration of Diamond Single Crystal during Annealing
Authors: Okotrub Alexander V. , Sedelnikova Olga V. , Gorodetskiy Dmitriy V. , Fedorenko Anastasiya D. , Asanov Igor P. , Palyanov Yury N. , Lapega Alina V. , Gurova Olga A. , Bulusheva Lyubov G.
Published: February 2023

Diamond is an important material for electrical and electronic devices. Because the diamond is in contact with the metal in these applications, it becomes necessary to study the metal–diamond interaction and the structure of the interface, in particular, at elevated temperatures. In this work, we study the interaction of the (100) and (111) surfaces of a synthetic diamond single crystal with spattered titanium and molybdenum films. Atomic force microscopy reveals a uniform coating of titanium and the formation of flattened molybdenum nanoparticles. A thin titanium film is completely oxidized upon contact with air and passes from the oxidized state to the carbide state upon annealing in an ultrahigh vacuum at 800 °C. Molybdenum interacts with the (111) diamond surface already at 500 °C, which leads to the carbidization of its nanoparticles and catalytic graphitization of the diamond surface. This process is much slower on the (100) diamond surface; sp2-hybridized carbon is formed on the diamond and the top of molybdenum carbide nanoparticles, only when the annealing temperature is raised to 800 °C. The conductivity of the resulting sample is improved when compared to the Ti-coated diamond substrates and the Mo-coated (111) substrate annealed at 800 °C. The presented results could be useful for the development of graphene-on-diamond electronics.
Multifunctional BiOI/SiO2/Fe3O4@n-Docosane Phase-Change Microcapsules for Waste Heat Recovery and Wastewater Treatment
Authors: Jing Jianwei , Liu Huan , Wang Xiaodong
Published: February 2023

Waste heat and organic contaminants are significant issues in water pollution, which has caused ecological problems and threatened human health. To provide an effective solution for wastewater recovery, we designed a novel type of multifunctional phase-change microcapsule. This type of microcapsule was synthesized using n-docosane as a core and a SiO2/Fe3O4 composite as a base shell through in situ interfacial polycondensation with the assistance of a Fe3O4 nanoparticle as a Pickering emulsion stabilizer, followed by the deposition of BiOI nanosheets on the surface of the SiO2/Fe3O4 composite shell. Benefiting from the n-docosane core, the resultant microcapsules obtained phase-change enthalpies of 46.8–115.7 J/g for absorbing waste heat from wastewater. The deposited BiOI nanosheets promoted photocatalysis for the microcapsules to degrade organic contaminants in wastewater. Owing to the magnetic response of the Fe3O4 nanoparticles, the separability and recyclability of the microcapsules were improved significantly by magnetic separation. Moreover, the microcapsules demonstrate outstanding phase-change reversibility, thermal cycling stability, and shape stability due to the tight SiO2/Fe3O4 composite shell. This study provides a promising approach for designing and developing multifunctional phase-change microcapsules for waste heat recovery and wastewater treatment.
Protection of Patinated Bronze with Long-Chain Phosphonic Acid/Organic Coating Combined System
Authors: Mikić Dajana , Otmačić Ćurković Helena
Published: February 2023

Bronze cultural heritage in urban areas is susceptible to decay due to the significant amount of pollutants present in the air. This causes the dissolution of bronze and the patina on its surface. The efficient protection of outdoor bronze cultural heritage is still an unresolved problem. The aim of this work is to investigate 16-phosphonohexadecanoic acid as an environmentally friendly and non-toxic corrosion inhibitor for patinated bronze. The corrosion protection of sulphide-patinated bronze by phosphonic acid alone and in combination with acrylic coating Paraloid B-72 is examined. In order to achieve efficient corrosion protection, various parameters of the phosphonic acid application were studied. The efficiency of protection is examined by electrochemical impedance spectroscopy (EIS) during the immersion in simulated acid rain solution and after exposure to a corrosion chamber. It was found that the studied phosphonic acid provides corrosion protection to patinated bronze and significantly improves the protective properties of Paraloid B72. This was also confirmed by scanning electron microscopy (SEM) examination of the coating surface after exposure to a corrosive environment.
Preparation and Performance of Multilayer Si-B-C-N/Diamond-like Carbon Gradient Films
Authors: Duan Jiaqi , Li Minghan , Wang Wenzhi , Huang Ziming , Jiang Hong , Ma Yanping
Published: February 2023

Si-B-C-N/diamond-like carbon (DLC) gradient films with different layers were prepared on a glass substrate by radio frequency magnetron sputtering, and the structure and surface morphology of the resulting films were analyzed by scanning electron microscopy, Raman spectrometry, and X-ray photoelectron spectroscopy. The mechanical and optical properties of the films were studied using a multifunctional material mechanical testing system, UV-Vis spectrophotometer, and micro-Vickers hardness tester. The gradient structure promotes the formation of sp3 bonds and improves the hardness and optical transmittance of the resulting films. Among the prepared films, the single-layer Si-B-C-N/DLC gradient film shows the highest optical transmittance (97%). Film–substrate adherence is strengthened by the introduction of the gradient structure. The best adhesion was obtained with a double-layer Si-B-C-N/DLC gradient film. Suitable anti-wear properties were exhibited in both dry (0.18) and wet (0.07) conditions. In this paper, evaluation of the microstructural, optical, and mechanical properties of the films could provide new insights into improvements in the bonding force of glass-based DLC films and enrich the experimental data of DLC multilayer film systems.