bluuebunny/crossref_metadata_2025 huggingface dataset:
Comment on Matsumoto et al. Remimazolam’s Effects on Postoperative Nausea and Vomiting Are Similar to Those of Propofol after Laparoscopic Gynecological Surgery: A Randomized Controlled Trial. J. Clin. Med. 2023, 12, 5402
Authors: Su Kai , Xue Fu-Shan , Cheng Yi
Published: February 2024

The recent article published in this journal by Matsumoto et al. [...]
Multidisciplinary and Coordinated Management of Osteoporotic Vertebral Compression Fractures: Current State of the Art
Authors: Al Taha Khalid , Lauper Nicolas , Bauer David E. , Tsoupras Andreas , Tessitore Enrico , Biver Emmanuel , Dominguez Dennis E.
Published: February 2024

Osteoporotic vertebral compression fractures (OVCFs) present a significant health concern, affecting a substantial portion of the older adult population worldwide. This narrative review explores the prevalence, diagnostic challenges and management strategies for OVCFs. Despite the increasing incidence and impact on morbidity and mortality, existing clinical guidelines lack consistency and clear diagnostic and therapeutic recommendations. The review addresses key questions faced by physicians dealing with older adult patients experiencing acute back pain, offering insights into triage, radiological assessments and classification systems. We propose a comprehensive algorithm for clearing OVCF, considering clinical presentation, radiological findings and morphological aspects. Emphasis is placed on the importance of medically treating osteoporosis alongside OVCF management. The review encompasses relevant literature from 1993 to 2023, provides a detailed discussion on triage issues and incorporates a clinically oriented classification system developed by the German Society for Orthopaedics and Trauma. The Material and Methods section outlines the extensive literature search carried out in PUBMED, encompassing clinical and experimental studies, systematic reviews and meta-analyses. The articles retained focused mainly on answering critical questions regarding radiological assessments, imaging modalities and the presence of a specific classification system for OVCFs. The review emphasises that the evaluation and management of OVCFs necessitates a multidisciplinary approach involving spine specialists and bone disease experts. It also addresses the role of conservative versus surgical treatments, with a focus on percutaneous vertebral augmentation. The conclusion summarises the algorithm derived for use in emergency departments and general practice, aiming to streamline OVCF management, reduce unnecessary examinations and ensure optimal patient care. The algorithm recommends primary diagnosis using computed tomography, with magnetic resonance imaging reserved for specific cases. The review advocates a holistic approach, integrating medical and surgical interventions to address the complex challenges posed by OVCFs in ageing populations.
Healing Process after High-Intensity Focused Ultrasound Treatment of Benign Skin Lesions: Dermoscopic Analysis and Treatment Guidelines
Authors: Calik Jacek , Zawada Tomasz , Bove Torsten , Dzięgiel Piotr , Pogorzelska-Antkowiak Anna , Mackiewicz Jacek , Woźniak Bartosz , Sauer Natalia
Published: February 2024

Background: High-Intensity Focused Ultrasound (HIFU) has emerged as a precise and non-invasive modality for tissue ablation and healing. This study presents a detailed dermoscopic analysis of skin healing post-High-Intensity Focused Ultrasound (HIFU) treatment, focusing on common benign skin lesions, such as seborrheic keratosis, sebaceous hyperplasia, vascular lesions, and sebaceous nevi. Methods: Prior to HIFU treatment, a comprehensive assessment was conducted, integrating ultrasound scanning and clinical evaluations. The TOOsonix System ONE-M was employed for HIFU treatments, with parameters tailored to each lesion type. Results: A common pattern observed across all lesions includes initial whitening post treatment, followed by scab formation and the development of a pink area with reparative vessels. This study, however, highlights distinct differences in fibrosis patterns and healing timelines across different lesion types. Each lesion type exhibited unique fibrosis patterns post treatment. Flatter variants of seborrheic keratosis healed within a month, displaying hypopigmentation and reparative vessels, alongside a distinct lattice fibrosis pattern in more verrucous forms, which took about two months to heal. Sebaceous hyperplasia, characterized by rapid healing within three weeks, demonstrated fibrosis with pink areas and perpendicular white lines, concluding with a slight depression. Vascular lesions varied in healing time based on depth, with superficial ones showing whitening and crust formation, while deeper lesions had vessel occlusion and size reduction accompanied by concentric fibrotic bands. Sebaceous nevi presented the longest healing duration of three months, characterized by amorphous white-gray structures, scab formation, and the emergence of pink areas with branching vessels, leading to clear skin with reduced white lines. Conclusions: in conclusion, this meticulous clinical evaluation highlights the unique healing characteristics and timelines for each skin lesion type treated with HIFU. These insights are invaluable for optimizing follow-up assessments, identifying potential complications, and refining treatment protocols. By providing detailed insights into the healing timelines and patterns for different types of lesions, patients can be better informed about their post-treatment journey.
Gender-Related Effectiveness of Personalized Post-COVID-19 Rehabilitation
Authors: Rzepka-Cholasińska Alicja , Ratajczak Jakub , Michalski Piotr , Kasprzak Michał , Kosobucka-Ozdoba Agata , Pietrzykowski Łukasz , Grzelakowska Klaudyna , Kubica Jacek , Kryś Jacek , Kubica Aldona
Published: February 2024

Background: Post-COVID-19 syndrome (PCS) may affect a substantial proportion of patients who have had COVID-19. The rehabilitation program might improve the physical capacity, functioning of the cardiopulmonary system, and mental conditions of these patients. This study aimed to investigate the effectiveness of personalized rehabilitation in patients with PCS according to gender. Methods: Adults who underwent a 6-week personalized PCS rehabilitation program were enrolled in a prospective post-COVID-19 Rehabilitation (PCR-SIRIO 8) study. The initial visit and the final visit included the hand-grip strength test, the bioimpedance analysis of body composition, and the following scales: modified Borg’s scale, Modified Fatigue Impact Scale (MFIS), Functioning in Chronic Illness Scale (FCIS), modified Medical Research Council (mMRC) dyspnea scale, and tests: 30 s chair stand test (30 CST), Six-Minute Walk Test (6MWT), Short Physical Performance Battery test (SPPB)e. Results: A total of 90 patients (54% female) underwent the rehabilitation program. Rehabilitation was associated with an increase in skeletal muscle mass (24.11 kg vs. 24.37 kg, p = 0.001) and phase angle (4.89° vs. 5.01°, p = 0.001) and with a reduction in abdominal fat tissue volume (3.03 L vs. 2.85 L, p = 0.01), waist circumference (0.96 m vs. 0.95 m, p = 0.001), and hydration level (83.54% vs. 82.72%, p = 0.001). A decrease in fat tissue volume and an increase in skeletal muscle mass were observed only in females, while an increase in grip strength was noticed selectively in males. Patients’ fatigue (modified Borg’s scale, MFIS), physical capacity (30 CST, 6MWT), balance (SPPB), dyspnea (mMRC), and functioning (FICS) were significantly improved after the rehabilitation regardless of gender. Conclusions: Personalized rehabilitation improved the body composition, muscle strength, and functioning of patients diagnosed with PCS. The beneficial effect of rehabilitation on body composition, hydration, and phase angle was observed regardless of gender.
Lessons from the Archives: Understanding Historical Agricultural Change in the Southern Great Plains
Authors: Carrasco Galvan Georgina Belem , Vadjunec Jacqueline M. , Fagin Todd D.
Published: February 2024

In the US, agriculture rapidly expanded beginning in the 1850s, influenced by homesteader policies and new technologies. With increased production also came widespread land-use/land-cover change. We analyze historical agricultural policies and associated land and water use trajectories with a focus on the Southern Great Plains (SGPs). Rapid changes in agriculture and reoccurring drought led to the infamous Dust Bowl, triggering new agricultural and land management policies, with lasting impacts on the landscape. To understand historical agricultural change, we use mixed methods, including archival literature and historical agricultural census data (1910 to 2017) from three counties in a tri-state (Oklahoma, New Mexico, Colorado) area of the SGPs. Our archival policy and agricultural census analysis illustrates 110 years of agricultural change, showing that agricultural policies and technological advances play an integral role in the development of agroecological systems, especially the Conservation Reserve Program (CRP), the Environmental Quality Incentives Program (EQIP), and the Livestock Forage Disaster Program (LFP). Further, while communities began with distinct agricultural practices, agricultural policy development resulted in increasing uniformity in crop and livestock practices. The results suggest that there are sustainability lessons to be learned by looking to the land and water trajectories and accompanying unintended consequences of the past.
How to Perceive National Governance Networks in the Global Commons of the Earth’s Surface: A Case Study of the Antarctic
Authors: Li Chu , Shen Wenjin
Published: February 2024

The destiny of mankind is closely intertwined, and exploring new paths for the governance of the global commons of the earth’s surface (GCES) has become a worldwide topic. Thus, this paper attempts to carry out the following work by taking the Antarctic as an example: (1) Identify the characteristics of the governance subjects by using a literature review and the inductive analysis method. (2) Construct a network of responsive relationships among the governance subjects based on the evolutionary game approach. This study found the following: (1) A multi-subject participation in governance, i.e., with the Antarctic Treaty parties as the core, the seven major organizations as the main force, the United Nations as the support, enterprises as the emerging force, and other countries as the potential subjects. (2) Response-relational networks have high clustering coefficients and characteristic path lengths close to those of random networks, with significant small-world features of relational networks. (3) As important components of the benefit function, long-term benefits and benefit intensities together influence cooperative strategies for governance in the Antarctic. In the future, we should actively focus on long-term interests based on the concept of a community with a shared future for mankind, improve the governance structure at the right time, and strive to build a robust globalization.
A Classical Molecular Dynamics Study of the Effect of the Atomic Force Microscope Tip Shape, Size and Deformation on the Tribological Properties of the Graphene/Au(111) Interface
Authors: Maden Cem , Ustunel Hande , Toffoli Daniele
Published: February 2024

Atomic force microscopes are used, besides their principal function as surface imaging tools, in the surface manipulation and measurement of interfacial properties. In particular, they can be modified to measure lateral friction forces that occur during the sliding of the tip against the underlying substrate. However, the shape, size, and deformation of the tips profoundly affect the measurements in a manner that is difficult to predict. In this work, we investigate the contribution of these effect to the magnitude of the lateral forces during sliding. The surface substrate is chosen to be a few-layer AB-stacked graphene surface, whereas the tip is initially constructed from face-centered cubic gold. In order to separate the effect of deformation from the shape, the rigid tips of three different shapes were considered first, namely, a cone, a pyramid and a hemisphere. The shape was seen to dictate all aspects of the interface during sliding, from temperature dependence to stick–slip behavior. Deformation was investigated next by comparing a rigid hemispherical tip to one of an identical shape and size but with all but the top three layers of atoms being free to move. The deformation, as also verified by an indentation analysis, occurs by means of the lower layers collapsing on the upper ones, thereby increasing the contact area. This collapse mitigates the friction force and decreases it with respect to the rigid tip for the same vertical distance. Finally, the size effect is studied by means of calculating the friction forces for a much larger hemispherical tip whose atoms are free to move. In this case, the deformation is found to be much smaller, but the stick–slip behavior is much more clearly seen.
Chlorido-pentamethylcyclopentadienyl-[2-(2-pyridyl-кN)-ferrocenyl-кC]-iridium(III)
Authors: Weigand Stefan , Sünkel Karlheinz
Published: February 2024

Treatment of 2-pyridyl-ferrocene wit [Cp*IrCl2]2 in the presence of NaOAc produces the title compound Cp*ClIr[(C5H3C5H4N-кN,кC)Fe(C5H5)] (2) in low yield. A crystal structure determination shows the (SpSIr/RpRIr)-2 enantiomeric pair of diastereomers.
Synthesis and Anti-Inflammatory Activity of (Z)-4-(2-(3-Oxopiperazin-2-ylidene)acetyl)benzoic Acid
Authors: Dmitriev Maksim V. , Khramtsova Ekaterina E. , Apuskin Danila Y. , Andreev Alexander I. , Kovalenko Ilya I. , Mashevskaya Irina V. , Maslivets Andrey N.
Published: February 2024

Non-steroidal anti-inflammatory drugs (NSAIDs) are an important class of medications; however, they have some drawbacks. We are developing a new NSAID with pronounced anti-inflammatory and analgesic activities and a very low toxicity—(Z)-3-(2-oxo-2-(p-tolyl)ethylidene)piperazin-2-one (piron). In this work, we describe the synthesis of the main metabolite of piron—(Z)-4-(2-(3-oxopiperazin-2-ylidene)acetyl)benzoic acid. The anti-inflammatory activity of the synthesized metabolite was determined in vivo.
Relative Entropy Application to Study the Elastoplastic Behavior of S235JR Structural Steel
Authors: Kamiński Marcin , Strąkowski Michał
Published: February 2024

The main issue in this work is to study the limit functions necessary for the reliability assessment of structural steel with the use of the relative entropy apparatus. This will be done using a few different mathematical theories relevant to this relative entropy, namely those proposed by Bhattacharyya, Kullback–Leibler, Jeffreys, and Hellinger. Probabilistic analysis in the presence of uncertainty in material characteristics will be delivered using three different numerical strategies—Monte Carlo simulation, the stochastic perturbation method, as well as the semi-analytical approach. All of these methods are based on the weighted least squares method approximations of the structural response functions versus the given uncertainty source, and they allow efficient determination of the first two probabilistic moments of the structural responses including stresses, displacements, and strains. The entire computational implementation will be delivered using the finite element method system ABAQUS and computer algebra program MAPLE, where relative entropies, as well as polynomial response functions, will be determined. This study demonstrates that the relative entropies may be efficiently used in reliability assessment close to the widely engaged first-order reliability method (FORM). The relative entropy concept enables us to study the probabilistic distance of any two distributions, so that structural resistance and extreme effort in elastoplastic behavior need not be restricted to Gaussian distributions.
Studies of Auxetic Structures Assembled from Rotating Rectangles
Authors: Plewa Julian , Płońska Małgorzata , Junak Grzegorz
Published: February 2024

The subject of the work is analysis, which presents a renowned auxetic structure based on so-called rotating polygons, which has been subject to modification. This modification entails introducing pivot points on unit cell surfaces near rectangle corners. This innovative system reveals previously unexplored correlations between Poisson’s ratio, the ratio of rectangle side lengths, pivot point placement, and structural opening. Formulas have been derived using geometric relationships to compute the structure’s linear dimensions and Poisson’s ratio. The obtained findings suggest that Poisson’s ratio is intricately tied to the structure’s opening degree, varying as the structure undergoes stretching. Notably, there are critical parameter limits beyond which Poisson’s ratio turns positive, leading to the loss of auxetic properties. For elongated rectangles, extremely high negative Poisson’s ratio values are obtained, but only for small opening angles, while with further stretching, the structure loses its auxetic properties. This observed trend is consistent across a broad category of structures comprised of rotating rectangles.
Effects of C and Al Alloying on Constitutive Model Parameters and Hot Deformation Behavior of Medium-Mn Steels
Authors: Guo Guangshun , Wang Mingming , Ji Hongchao , Zhang Xiaoyan , Li Dongdong , Wei Chenyang , Zhang Fucheng
Published: February 2024

Single-pass isothermal hot compression tests on four medium-Mn steels with different C and Al contents were conducted using a Gleeble-3500 thermal simulation machine at varying deformation temperatures (900–1150 °C) and strain rates (0.01–5 s−1). Based on friction correction theory, the friction of the test stress–strain data was corrected. On this basis, the Arrhenius constitutive model of experimental steels considering Al content and strain compensation and hot processing maps of different experimental steels at a strain of 0.9 were established. Moreover, the effects of C and Al contents on constitutive model parameters and hot processing performance were analyzed. The results revealed that the increase in C content changed the trend of the thermal deformation activation energy Q with the true strain. The Q value of 2C7Mn3Al increased by about 50 KJ/mol compared with 7Mn3Al at a true strain greater than 0.4. In contrast, increasing the Al content from 0 to 1.14 wt.% decreased the activation energy of thermal deformation in the true strain range of 0.4–0.9. Continuing to increase to 3.30 wt.% increased the Q of 7Mn3Al over 7Mn by about 65 KJ/mol over the full strain range. In comparison, 7Mn1Al exhibited the best hot processing performance under the deformation temperature of 975–1125 °C and strain rate of 0.2–5 s−1. This is due to the addition of C element reduces the δ-ferrite volume fraction, which leads to the precipitation of κ-carbides and causes the formation of microcracks; an increase in Al content from 0 to 1.14 wt.% reduces the austenite stability and improves the hot workability, but a continued increase in the content up to 3.30 wt.% results in the emergence of δ-ferrite in the microstructure, which slows down the austenite DRX and not conducive to the hot processing performance.
The Mechanical Performance and Reaction Mechanism of Slag-Based Organic–Inorganic Composite Geopolymers
Authors: Xing Xiaotong , Xu Weiting , Zhang Guihua , Wen Xilian
Published: February 2024

A series of organic–inorganic composite geopolymer paste samples were prepared with slag-based geopolymer and three types of hydrophilic organic polymers, i.e., PVA, PAA, and CPAM, by ordinary molding and pressure-mixing processes. The reaction mechanism between slag-based geopolymer and organic polymers was studied by FT-IR, NMR, and SEM techniques. The experimental results showed that the slag-based geopolymer with the addition of 3% PVA presented the highest 28-day flexural strength of 19.0 MPa by means of a pressure-mixing process and drying curing conditions (80 °C, 24 h) compared with the geopolymers incorporating PAA and CPAM. A more homogeneous dispersion morphology was also observed by BSE and SEM for the 3% PVA-incorporated slag-based geopolymer. The FT-IR testing results confirmed the formation of a C–O–Si (Al) bond between PVA and the slag-based geopolymer. The deconvolution of the Q3 and Q2(1Al) species obtained by 29Si NMR testing manifested the addition of PVA and increased the length of the silicon backbone chain in the geopolymer. These findings confirmed that a composite geopolymer with high toughness can be produced based on the interpenetrating network structure formed between organic polymers and inorganic geopolymer.
The Impact of Vegetable Fibres on the Shrinkage and Mechanical Properties of Cob Materials
Authors: Kabore Aguerata , Ouellet-Plamondon Claudiane M.
Published: February 2024

This study examined the shrinkage rate and mechanical properties of cob samples. Cob is a natural building material composed of clay, water, and varying amounts of plant fibres. The red and beige cob materials in this study containing 3% and 6% wheat fibres were manufactured by hand with clay, bulk fibres (short and long fibres), and a 25% water ratio (water/clay) in order to make their manufacture and use on construction sites feasible and simple. The reference samples were mixed with clay, 25% water, and 0% wheat fibre. The mechanical properties were assessed through compression and flexural tests after 28 and 120 days. The results showed that the fibre addition decreased the bulk density of the composites from 1902 kg/m3 to 1264 kg/m3. The compressive strength increased from 1.8 MPa to 4.57 MPa for the red clay samples and from 1.65 MPa to 4.61 MPa for the beige clay samples at 28 days. The compressive strength of each mixture decreased slightly with age for the red and beige clay samples, respectively. Conversely, the flexural strength increased with age for the samples reinforced with 3% and 6% fibres. The results also showed that the cob samples can deform without breaking. Increasing the fibre content in the mix resulted in a significant reduction in the shrinkage rate and an increase in the mass loss rate during thermogravimetric analysis. This analysis showed a total mass loss of approximately 5.64%, 6.12%, and 44.87% for the red clay, beige clay, and fibres, respectively. An average volume shrinkage of 1% was observed for the samples with 6% fibre content. The cob discussed in this article can be used as a filling material. In large quantities, it can be made by hand, with feet protected by boots, or with the use of a mixer. The environmental benefits are considerable, as the raw materials are renewable, and the manufacturing process is less energy-intensive.
Preparation of Chitin Nanofibers and Natural Rubber Composites and Their Triboelectric Nanogenerator Applications
Authors: Petchnui Kattaliya , Uwanno Teerayut , Phonyiem Reilly Mayuree , Pinming Chinathun , Treetong Alongkot , Yordsri Visittapong , Moolsradoo Nutthanun , Klamcheun Annop , Wongwiriyapan Winadda
Published: February 2024

Triboelectric nanogenerators (TENGs) have gained significant attention as promising energy-harvesting devices that convert mechanical energy into electrical energy through charge separation induced by friction and electrostatic induction. In this study, we explore the utilization of biowaste shrimp shell-extracted chitin nanofiber (ChNF) as a viable eco-friendly material for TENG applications. Composite materials were prepared by incorporating ChNF into natural rubber (NRL) at loading levels of 0.1 and 0.2 wt% (NRL/ChNF) to form the TENG triboelectric layer. ChNFs with a uniform width of approximately 10–20 nm were successfully extracted from the shrimp shells through a simple mechanical procedure. The NRL/ChNF composites exhibited enhanced mechanical properties, as evidenced by a higher Young’s modulus (3.4 GPa) compared to pure NRL. Additionally, the NRL/ChNF composites demonstrated an increased dielectric constant of 3.3 at 0.1 MHz. Moreover, the surface potential difference of NRL increased from 0.182 V to 1.987 V in the NRL/ChNF composite. When employed as the triboelectric layer in TENG, the NRL/ChNF composites exhibited significant improvement in their output voltage, with it reaching 106.04 ± 2.3 V. This enhancement can be attributed to the increased dielectric constant of NRL/ChNF, leading to enhanced charge exchange and charge density. This study presents a straightforward and environmentally friendly technique for preparing sustainable natural materials suitable for energy-harvesting devices.
Mechanical Characterization of Multifunctional Metal-Coated Polymer Lattice Structures
Authors: Wang Lizhe , He Liu , Liu Fuyuan , Yuan Hang , Li Ji , Chen Min
Published: February 2024

Metal-coated lattice structures hold significant promise for customizing mechanical properties in diverse industrial applications, including the mechanical arms of unmanned aerial vehicles. However, their intricate geometries pose computational challenges, resulting in time-intensive and costly numerical evaluations. This study introduces a parameterization-based multiscale method to analyze body-centered cubic lattice structures with metal coatings. We establish the validity and precision of our proposed method with a comparative analysis of numerical results at the Representative Volume Element (RVE) scale and experimental findings, specifically addressing both elastic tensile and bending stiffness. Furthermore, we showcase the method’s accuracy in interpreting the bending stiffness of coated lattice structures using a homogenized material-based solid model, underscoring its effectiveness in predicting the elastic properties of such structures. In exploring the mechanical characterization of coated lattice structures, we unveil positive correlations between elastic tensile stiffness and both coating thickness and strut diameter. Additionally, the metal coating significantly enhances the structural elastic bending stiffness multiple times over. The diverse failure patterns observed in coated lattices under tensile and bending loads primarily stem from varied loading-induced stress states rather than external factors. This work not only mitigates computational challenges but also successfully bridges the gap between mesoscale RVE mechanical properties and those at the global structural scale.
Transferability of Temperature Evolution of Dissimilar Wire-Arc Additively Manufactured Components by Machine Learning
Authors: Fagersand Håvard Mo , Morin David , Mathisen Kjell Magne , He Jianying , Zhang Zhiliang
Published: February 2024

Wire-arc additive manufacturing (WAAM) is a promising industrial production technique. Without optimization, inherent temperature gradients can cause powerful residual stresses and microstructural defects. There is therefore a need for data-driven methods allowing real-time process optimization for WAAM. This study focuses on machine learning (ML)-based prediction of temperature history for WAAM-produced aluminum bars with different geometries and process parameters, including bar length, number of deposition layers, and heat source movement speed. Finite element (FE) simulations are used to provide training and prediction data. The ML models are based on a simple multilayer perceptron (MLP) and performed well during baseline training and testing, giving a testing mean absolute percentage error (MAPE) of less than 0.7% with an 80/20 train–test split, with low variation in model performance. When using the trained models to predict results from FE simulations with greater length or number of layers, the MAPE increased to an average of 3.22% or less, with greater variability. In the cases of greatest difference, some models still returned a MAPE of less than 1%. For different scanning speeds, the performance was worse, with some outlier models giving a MAPE of up to 14.91%. This study demonstrates the transferability of temperature history for WAAM with a simple MLP approach.
Preparation and Performance Study of High-Strength and Corrosion-Resistant Cement-Based Materials Applied in Coastal Acid Rain Areas
Authors: Wang Junfeng , Zhang Shaoxuan , Fu Qionglin , Hu Yang , Lu Liulei , Wang Zhihao
Published: February 2024

Investigations regarding the preparation and durability of cement-based materials applied in specific coastal acid rain environments are scarce, particularly those involving the addition of four auxiliary cementitious materials (ACMs) to cement for modification. To improve the durability of concrete structures in coastal acid rain areas, a systematic study was conducted regarding the preparation of high-strength and corrosion-resistant cement-based materials using ACM systems composed of fly ash (FA), granulated blast furnace slag (GBFS), silica fume (SF), and desulfurization gypsum (DG) instead of partial cement. Through an orthogonal experimental design, the effect of the water–binder ratio, cementitious ratio, and replacement cement ratio on the compressive strength, corrosion resistance coefficient, and chloride ion permeability coefficient of the materials were analyzed and the mix proportions of the materials were evaluated and optimized using the comprehensive scoring method. The results show that implementing a FA:GBFS:SF:DG ratio of 2:6:1:1 to replace 60% of cement allows the consumption of calcium hydroxide crystals generated through cement hydration, promotes the formation of ettringite, optimizes the pore structures of cementitious materials, and improves the compressive strength, acid corrosion resistance, and chloride ion permeability of the materials. This study provides a reference for selecting concrete materials for buildings in coastal acid rain environments.
Effect of Graphene on the Performance of Silicon–Carbon Composite Anode Materials for Lithium-Ion Batteries
Authors: Ni Chengyuan , Xia Chengdong , Liu Wenping , Xu Wei , Shan Zhiqiang , Lei Xiaoxu , Qin Haiqing , Tao Zhendong
Published: February 2024

(Si/graphite)@C and (Si/graphite/graphene)@C were synthesized by coating asphalt-cracked carbon on the surface of a Si-based precursor by spray drying, followed by heat treatment at 1000 °C under vacuum for 2h. The impact of graphene on the performance of silicon–carbon composite-based anode materials for lithium-ion batteries (LIBs) was investigated. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) images of (Si/graphite/graphene)@C showed that the nano-Si and graphene particles were dispersed on the surface of graphite, and thermogravimetric analysis (TGA) curves indicated that the content of silicon in the (Si/graphite/graphene)@C was 18.91%. More bituminous cracking carbon formed on the surface of the (Si/graphite/graphene)@C due to the large specific surface area of graphene. (Si/Graphite/Graphene)@C delivered first discharge and charge capacities of 860.4 and 782.1 mAh/g, respectively, initial coulombic efficiency (ICE) of 90.9%, and capacity retention of 74.5% after 200 cycles. The addition of graphene effectively improved the cycling performance of the Si-based anode materials, which can be attributed to the reduction of electrochemical polarization due to the good structural stability and high conductivity of graphene.
Correction: Pontes do Nascimento et al. Synthesis of Mesoporous Zn1−xMxAl2O4 Substituted by Co2+ and Ni2+ Ions and Application in the Photodegradation of Rhodamine B. Materials 2020, 13, 2150
Authors: Pontes do Nascimento Nilson Machado , Machado de Lima Bárbara Ronara , Zamian José Roberto , Ferreira da Costa Carlos Emmerson , Adriano Santos do Nascimento Luís , Luque Rafael , Filho Geraldo Narciso da Rocha
Published: February 2024

In the original publication [...]
Flame-Retardant and Transparent Unsaturated Polyester Based on P/N Liquid Flame Retardants and Modified Halloysite Nanotubes
Authors: Dou Yanli , Ju Aixun , Zhong Zheng , Huo Yutong , Yao Weiguo
Published: February 2024

Unsaturated polyester resin (UPR) with excellent flame retardant is mainly obtained by adding large amounts of flame retardants, usually at the expense of mechanical properties. In this work, a reactive flame retardant containing phosphorus and nitrogen (DOPO-N) was successfully synthesized and incorporated in UPR as a crosslinker. The mechanical and flame-retardant properties of UPR composites were enhanced. UPR/30DOPO-N passed a UL-94 V-1 rating with a limiting oxygen index (LOI) of 30.8%. The tensile strength of UPR/30DOPO-N increased by 24.4%. On this basis, a small amount of modified HNTs (VHNTs) was added to further improve the flame-retardant properties of the composite. With the introduction of 3 wt% VHNTs, the composite passed the UL-94 V-0 rating. The peak of heat release rate (PHRR) and total heat release (THR) of it decreased by 60.7% and 48.3%, respectively. Moreover, the detailed flame-retarding mechanism of DOPO-N and VHNTs was investigated by thermogravimetric infrared spectroscopy (TG-IR), Raman spectra, and X-ray photoelectron spectroscopy (XPS). It was found that DOPO-N played a role in quenching the flame in the gas phase and cooperated with VHNTs to enhance the barrier effect in the condensed phase.
Research on the Surface-State Parameterization of a Refill Friction Stir Spot Welding Joint Made of Aluminum Alloy and Its Connection to the Fracture Mode
Authors: Zhong Hua , Xu Guocheng , Dong Juan , Gu Xiaopeng , Fan Qiuyue
Published: February 2024

Surface features are crucial for assessing welding quality because they serve as an intuitive depiction of the quality of the joint and have a major influence on welding strength. According to the characteristics of the refill friction stir spot welding (RFSSW) process and an analysis of the surface-state and internal morphology of RFSSW joints, a method of predicting the mechanical properties of RFSSW joints based on surface-state characteristics was proposed. In this paper, a laser-ranging sensor was used to characterize the surface state of RFSSW joints, and parametric characterization methods of the surface-state features of RFSSW joints were proposed. On this basis, a support vector machine was used to predict and analyze the fracture mode of RFSSW joints. The accuracy of the analysis of the test samples reached 95.8%. This paper provides a more efficient and convenient new method for the quality evaluation of RFSSW joints.
Application of the Van Cittert Algorithm for Deconvolving Loss Features in X-ray Photoelectron Spectroscopy Spectra
Authors: Speranza Giorgio
Published: February 2024

The convolution of two physical entities, denoted as f and g, delineates the manner in which one entity undergoes modification in response to the other. This transformative process is mathematically represented by the expression f ⨂ g, symbolizing the convolution of the two entities in a resultant function h. Frequently, it becomes imperative to comprehend the magnitude of the induced modifications. From the derived function h, a crucial step involves the separation of the two original signals, a process commonly referred to as deconvolution. Various techniques have been proposed to facilitate the calculation of the deconvolution, with one notable approach originating in 1931 by van Cittert. The algorithm, based on an iterative method, has been scrutinized over time, notably by Bracewell and, more recently, by Jansson. This work represents the current state-of-the-art, focusing specifically on the analysis of Auger spectra obtained through XPS. Emphasis is placed on delineating the procedural aspects of the analysis, and the algorithm utilized in the open-source software RxpsG is comprehensively described.
Investigation into the Effects of Crystalline Admixtures and Coatings on the Properties of Self-Healing Concrete
Authors: Shetiya Ravi Kumar , Elhadad Sara , Salem Ali , Fülöp Attila , Orban Zoltan
Published: February 2024

One fascinating concept for enhancing the durability and lifespan of concrete buildings involves the use of self-healing concrete. This study focuses on the effect of crystalline admixtures and coatings on various properties of self-healing concrete and provides a comparison with traditional concrete. Four different concrete mixtures were prepared to assess their effectiveness in bridging crack openings, their flexural and compressive strengths, and water absorption. Various testing methods, including destructive, semi-destructive, and non-destructive tests, were used in this research. The capacity of the mixes to repair themselves was assessed on the destroyed and semi-destroyed test specimens using crack-healing and microstructure testing. Additionally, all mixtures were also subjected to the slump cone test and air content test in order to investigate the characteristics of the concrete in its fresh state. The findings demonstrate that crystalline coating and admixture combinations have significant potential for healing concrete. The compressive and bending strengths of self-healing concrete mixtures were shown to be slightly higher compared to traditional concrete when the additive dose was increased. Self-healing concrete mixtures also exhibited much lower water absorption, a tightly packed and improved microstructure, and signs of healed gaps, all of which indicate greater durability.
Application of Microfracture Analysis to Fatigue Fractures in Materials through Non-Destructive Tests
Authors: Sánchez-Santana Ulises , Presbítero-Espinosa Gerardo , Quiroga-Arias José María
Published: February 2024

Fatigue fractures in materials are the main cause of approximately 80% of all material failures, and it is believed that such failures can be predicted and mathematically calculated in a reliable manner. It is possible to establish prediction modalities in cases of fatigue fractures according to three fundamental variables in fatigue, such as volume, number of fracture cycles, as well as applied stress, with the integration of Weibull constants (length characteristic). In this investigation, mechanical fatigue tests were carried out on specimens smaller than 4 mm2, made of different industrial materials. Their subsequent analysis was performed through precision computed tomography, in search for microfractures. The measurement of these microfractures, along with their metrics and classifications, was recorded. A convolutional neural network trained with deep learning was used to achieve the detection of microfractures in image processing. The detection of microfractures in images with resolutions of 480 × 854 or 960 × 960 pixels is the primary objective of this network, and its accuracy is above 95%. Images that have microfractures and those without are classified using the network. Subsequently, by means of image processing, the microfracture is isolated. Finally, the images containing this feature are interpreted using image processing to obtain their area, perimeter, characteristic length, circularity, orientation, and microfracture-type metrics. All values are obtained in pixels and converted to metric units (μm) through a conversion factor based on image resolution. The growth of microfractures will be used to define trends in the development of fatigue fractures through the studies presented.
Evaluation Method of Fatigue Life for Asphalt Pavement on the Steel Bridge Deck Based on the Inhomogeneous Poisson Stochastic Process
Authors: Xu Xunqian , Wan Guozhi , Kang Fengyi , Li Shue , Huang Wei , Li Yu , Li Qi , Lv Chen
Published: February 2024

The paving layer on the steel box girder bridge deck is widely used when constructing pavements for steel bridges. Owing to the orthotropic feature of steel decks, a transverse clapboard and rib can lead to a concentration of stress. Consequently, fatigue cracks are often identified in asphalt concrete pavement layers due to re-compaction caused by heavy vehicles. This study aims to derive an evaluation method of fatigue life for asphalt pavement based on the inhomogeneous Poisson stochastic process in view of the highly random and uncertain working conditions of layered composite structures. According to the inhomogeneous Poisson stochastic process, along with Miner’s fatigue damage accumulation theory and the linear elastic fracture mechanics theory, the fatigue life formula could be deduced. Meanwhile, fatigue experiments for asphalt concrete are designed to investigate the correlation between the theoretical formula and the actual fatigue damage life of the material. Compared with the test, the accuracy error is within 10%, which is better than other traditional methods. Therefore, the fatigue life prediction model could better reflect the loading order effect and the interaction between loads, providing a new path for the fatigue reliability design of steel bridge deck asphalt pavement.
Carbon-Based Functional Nanomaterials as Tools for Controlling the Kinetics of Tribochemical Reactions
Authors: Ozimina Dariusz , Kulczycki Andrzej , Janas Dawid , Desaniuk Tomasz , Deliś Maciej
Published: February 2024

The aim of this article is to experimentally determine the role of the environment, consisting of a base oil (PAO), carbon nanomaterials, and optional other additives, as well as the kind of metal in contact with the lubrication film, in the stimulation of zinc dialkyldithiophosphate (ZDDP) additives’ effectiveness during protective film formation. This paper focuses on the role of carbon nanostructures in energy transportation and conversion during tribological processes. An antistatic additive (ASA) (not used in lubricating oils) for jet fuels was added to disturb the process of energy conduction (electric charges) through the lubricant film and thus determine how this disturbance affects the kinetics of the ZDDP triboreaction and, consequently, the linear wear. To achieve this research goal, two types of tribological testing devices were used: an Anton Paar tribometer (TRB) and a triboelectric tribometer (TET). The novelty of the present research is in the use of the method for disturbing the flow of charge/energy through the lubricant film with an antistatic additive for jet fuels, ASA, to influence the impact of this energy on the antiwear properties of ZDDP. The following conclusions were drawn: (1) carbon-based nanostructures, i.e., CNTs, AuCNTs, graphene, and fullerenes, are able to change the rate of chemical reactions of ZDDP during tribological processes; (2) CNTs have the ability to catalyze tribochemical reactions of ZDDP, while graphene and fullerenes are not able to perform this effectively; (3) AuCNT takes the role of an inhibitor during ZDDP’s triboreaction; and (4) by discharging electric charge/energy, ASA, in cooperation with CNT and AuCNT significantly reduces the rate of the ZDDP reaction.
Sliding and Fretting Wear Behavior of Biomedical Ultrafine-Grained TiNbZrTaFe/Si Alloys in Simulated Physiological Solution
Authors: Li Yuhua , Zhang Qian , He Yuxin , Zhao Rong , Chu Jinghui , Niu Libin , Qu Juxin
Published: February 2024

This work investigated the wear behavior of ultrafine-grained Ti65Nb23.33Zr5Ta1.67Fe5 (at.%, TNZTF) and Ti65Nb23.33Zr5Ta1.67Si5 (at.%, TNZTS) alloys fabricated by high-energy ball milling and spark plasma sintering. Wear tests were conducted in a simulated physiological solution under both reciprocating sliding and fretting wear conditions with different loads, frequencies, and stroke lengths. The microstructures, mechanical properties, and anti-wear properties of the investigated alloys were characterized. The results showed that the TNZTF and TNZTS alloys had much less wear volume than the commonly used Ti-6Al-4V (TC4) alloy and commercially pure titanium (CP-Ti). The TNZTF and TNZTS alloys exhibited much more smooth wear surfaces and shallower wear scars compared with TC4 and CP-Ti. The investigated alloys exhibited different wear mechanisms under the reciprocating sliding wear conditions, while they were similar under the fretting wear conditions. Compared with TC4 and CP-Ti, the fabricated TNZTF and TNZTS alloys showed a substantially higher wear resistance, owing to their ultrafine-grained microstructure and superior hardness. Additionally, the addition of Nb and Zr further enhanced the wear resistance by forming a protective Nb2O5 and ZrO2 oxide film. This work provides guidance for designing new biomedical titanium alloys with excellent wear resistance.
Resistance of Concrete with Various Types of Coarse Aggregate to Coupled Effects of Thermal Shocks and Chemicals
Authors: Hossain Muhammad Monowar , Al-Deen Safat , Shill Sukanta Kumer , Hassan Md Kamrul
Published: February 2024

Rigid pavements at military airfields experience surface deterioration within 6–18 months of construction. The cause of this degradation is mainly due to combined exposure to repeated heat shocks from jet engine exhaust and spilled aviation oils (hydrocarbons). Surface degradation occurs in the form of disintegration of aggregates and cement paste into small pieces that pose severe risks of physical injury to maintenance crews or damage to an aircraft engine. Since coarse aggregates typically occupy 60–80% of the concrete volume, aggregates’ thermal properties and microstructure should play a crucial role in the degrading mechanism. At high temperatures, concrete with lightweight aggregates is reported to have better performance compared to concrete with normal-weight aggregate. Thus, the present study carried out a detailed investigation of the mechanical and thermal performance of lightweight aggregate concrete exposed to the combined effects of high temperatures and hydrocarbon oils simultaneously. To replicate harsh airfield operating conditions, standard-sized concrete cylinders were exposed to elevated temperatures using an electric oven. Additionally, a mixture of equal parts of aircraft engine oil, hydraulic oil, and kerosene was applied before each exposure to high temperatures. To identify the resistance of different concrete with various lightweight coarse aggregates, pumice, perlite, lytag (sintered fly ash), and crushed brick were used as lightweight coarse aggregates in concrete. Also, basalt aggregate concrete was used as a reference. After curing, cylinders were tested for the ultimate strength. Later, after every 20 cyclic exposures, three cylinders from each aggregate type were tested for residual comprehensive strength, thermal, chemical, and microstructural (SEM) properties. Overall, concrete with crushed brick aggregate and lytag used in this study showed superior resistance to the simulated airfield conditions. The findings of this study will provide valuable insights to select an appropriate coarse aggregate type for military airfield pavement construction, aiming to effectively minimize surface spalling.
Analysis of Fuzzy Vector Spaces as an Algebraic Framework for Flag Codes
Authors: Bejines Carlos , Ojeda-Hernández Manuel , López-Rodríguez Domingo
Published: February 2024

Flag codes are a recent network coding strategy based on linear algebra. Fuzzy vector subspaces extend the notions of classical linear algebra. They can be seen as abstractions of flags to the point that several fuzzy vector subspaces can be identified to the same flag, which naturally induces an equivalence relation on the set of fuzzy vector subspaces. The main contributions of this work are the methodological abstraction of flags and flag codes in terms of fuzzy vector subspaces, as well as the generalisation of three distinct equivalence relations that originated from the fuzzy subgroup theory and study of their connection with flag codes, computing the number of equivalence classes in the discrete case, which represent the number of essentially distinct flags, and a comprehensive analysis of such relations and the properties of the corresponding quotient sets.
More General Ostrowski-Type Inequalities in the Fuzzy Context
Authors: Latif Muhammad Amer
Published: February 2024

In this study, Ostrowski-type inequalities in fuzzy settings were investigated. A detailed theory of fuzzy analysis is provided and utilized to establish the Ostrowski-type inequality in the fuzzy number-valued space. The results obtained in this research not only provide a generalization of the results of Dragomir but also give an extended version of the Ostrowski-type inequalities obtained by Anastassiou.