bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Dynamic Characteristics of Resilient Mount Under Preload
Authors: Park Sung-Ju , Park Byoungjae , Lee Joo-Yeob , Shin Yun-Ho , Jeong Chae-Lim , Kim Sung-Jae , Kim Kookhyun
Published: October 2024

Resilient mounts are essential for anti-vibration and shock absorption applications, making accurate predictions of their static and dynamic behaviors critical for effective design and mechanical performance. This study investigates static and dynamic characteristics of resilient mounts to predict their effects. Tension, compression, and shear tests were performed under quasi-static loading conditions to obtain stress-strain cycle curves. This study includes a review of the Yeoh hyperelastic model, which consists of three parameters, and discusses the calibration of these parameters to describe the hyperelastic material behavior. The parameters were validated through numerical analysis by comparing them with experimental results from quasi-static tests on the resilient mount. The dynamic behavior was further analyzed using modal analysis and frequency response simulations under various preload conditions. Results show that increasing preload significantly shifts the transmissibility curves and resonance peaks to lower frequencies. This study offers valuable insights into static and dynamic characteristics of resilient mounts, contributing to the design and optimization of vibration isolation systems for naval applications.
Strength Development and Environmental Impact of Waste-Glass-Based Cements Activated with Portland Cement, NaOH, Na-Silicate or Na-Carbonates at Ambient Temperature
Authors: Lemesre Louise , Idir Rachida , Cyr Martin
Published: October 2024

This paper presents an experimental approach to the study of the compressive strength, isothermal calorimetry and life cycle assessment (LCA) of alkali-activated pastes based on soda–lime–silica glass, established to investigate the effect of the nature and proportion of the activator. Four different activators are compared: Portland cement, sodium silicate, sodium carbonate (at four percentages by weight: 5, 10, 15 and 25 wt% relative to glass) and sodium hydroxide (3.5 wt%). Portland cement and sodium carbonate were added in dry form (powder), while sodium hydroxide (pellets) and silicate were used in solution. At room temperature, glass exhibited slow reaction kinetics, with mechanical performance increasing significantly beyond 28 days of curing. The nature of the activator had a direct impact on the mechanical performance of the activated glass. Cement-activated pastes and those containing 25 wt% of sodium carbonate developed strength at an early age (0–7 days). The other activators showed lower strength development before 28 days of reaction. While a higher activator content improved short-term performance, it also increased the environmental impact, primarily due to the activator. The LCA, conducted on 11 indicators, revealed that the environmental impact was largely driven by the type and amount of activator used. A performance impact indicator (PII) related to global warming was introduced to compare pastes with different performance values. At an early age (0–28 days), the PII was lower when the activator level was high but decreased over time as the strength improved. In terms of long-term performance (360 days), hydroxide and sodium carbonate (10 wt%) achieved compressive strengths of 91 and 74 MPa, respectively. These systems offered a balance between high performance and a reduced environmental impact, making them of interest for sustainable applications.
Effect of Recycled Asphalt Mixture and Solid Waste-Based Solidification Materials on Performance of Cold-Regenerated Asphalt Mixture
Authors: Shu Benan , Zeng Guodong , Ma Yunlong , Ren Yanfei , Zhu Maocong
Published: October 2024

In this study, an aging asphalt mixture was regenerated by a waste-based rejuvenator and cemented by solid waste-based solidification materials (SSMs). A splitting test, wheel tracking test, and three-point bending test were conducted to evaluate the properties of the regenerated asphalt mixture (RAM). The results reveal that the properties of the asphalt mixture were not diminished or were moderately enhanced by the 30% substitution of RAP. With the substitution of RAP to 100%, the splitting tensile strength, dynamic stability, and splitting strength ratio were decreased by 13%, 15%, and 5%, respectively. With the 100% substitution of SSMs for cement, the compressive strength, dynamic stability, flexural strain, and splitting strength ratios of the RAM were increased by 40%, 32%%, 14%, and 8%, respectively. The lightweight components can be supplemented, and low-temperature deformation and interlayer flowability can be improved by the incorporation of the rejuvenator. The generation of hydrated calcium silicate and ettringite for SSMs is greater than those of cement. The massive generation of ettringite has been observed to increase the solid phase volume by 120%, which may facilitate a more complete filling of the remaining pores in the RAM due to water evaporation. The regeneration and cement on green and the high performance of the rejuvenator and the SSM markedly enhanced RAM performance.
Deep Learning-Based Reconstruction of 3D Morphology of Geomaterial Particles from Single-View 2D Images
Authors: Zhao Jiangpeng , Xie Heping , Li Cunbao , Liu Yifei
Published: October 2024

The morphology of particles formed in different environments contains critical information. Thus, the rapid and effective reconstruction of their three-dimensional (3D) morphology is crucial. This study reconstructs the 3D morphology from two-dimensional (2D) images of particles using artificial intelligence (AI). More than 100,000 particles were sampled from three sources: naturally formed particles (desert sand), manufactured particles (lunar soil simulant), and numerically generated digital particles. A deep learning approach based on a voxel representation of the morphology and multi-dimensional convolutional neural networks was proposed to rapidly upscale and reconstruct particle morphology. The trained model was tested using the three particle types and evaluated using different multi-scale morphological descriptors. The results demonstrated that the statistical properties of the morphological descriptors were consistent for the real 3D particles and those derived from the 2D images and the model. This finding confirms the model’s validity and generalizability in upscaling and reconstructing diverse particle samples. This study provides a method for generating 3D numerical representations of geological particles, facilitating in-depth analysis of properties, such as mechanical behavior and transport characteristics, from 2D images.
Fully Physically Crosslinked Hydrogel with Ultrastretchability, Transparency, and Freezing-Tolerant Properties for Strain Sensor
Authors: Shang Pengbo , Ji Yang , Ji Feng
Published: October 2024

Nowadays, conductive hydrogels show significant prospects as strain sensors due to their good stretchability and signal transduction abilities. However, traditional hydrogels possess poor anti-freezing performance at low temperatures owing to the large number of water molecules, which limits their application scope. To date, constructing a hydrogel-based sensor with balanced stretchability, conductivity, transparency, and anti-freezing properties via simple methods has proven challenging. Here, a fully physically crosslinked poly(hydroxyethyl acrylamide)–glycerol–sodium chloride (PHEAA–Gl–NaCl) hydrogel was obtained by polymerizing hydroxyethyl acrylamide in deionized water and then soaking it in a saturated NaCl solution of glycerol and water. The PHEAA–Gl–NaCl hydrogel had good transparency (~93%), stretchability (~1300%), and fracture stress (~287 kPa). Owing to the presence of glycerol and sodium chloride, the PHEAA–Gl–NaCl hydrogel had good anti-freezing properties and conductivity. Furthermore, the PHEAA–Gl–NaCl hydrogel-based strain sensor possessed good sensitivity and cyclic stability, enabling the detection of different human motions stably and in a wide temperature range. Based on the above characteristics, the PHEAA–Gl–NaCl hydrogel has broad application prospects in flexible electronic materials.
Chromatic Adaption of Two Universal Composites: Spectrophotometric Analysis
Authors: Zotti Francesca , Ferrari Francesca , Penazzo Mattia , Lanzaretti Giorgia , Zerman Nicoletta
Published: October 2024

Objective: The purpose of this study was to evaluate the chromatic adaptability and color stability of two different composite resins, Omnichroma and Estelite Bulk-Fill Flow, in Class V restorations at different times. Materials and methods: Standardized Class V cavities were prepared on the labial surface of 34 extracted intact and noncarious human permanent molars. The dental elements were randomly divided into two groups according to the resin composite material. Group 1 was restored with Omnichroma (Tokuyama Dental Corporation Inc., Tokyo, Japan) and Group 2 was restored with Estelite BulkFill Flow Universal (Tokuyama Dental Corporation Inc., Tokyo, Japan). Color properties were assessed using a spectrophotometer, SpectroShadeTM Micro (MHT Optic Research, Niederhasli, Switzerland), at baseline (T0), immediately after Class V restoration (T1), 24 h after restoration (T2) and after thermocycling (T3) (ISO/TS 11405, 2015 protocol). Color difference (ΔE) was analyzed with a Student’s t-test and a Wilcoxon–Mann–Whitney test to evaluate the differences, in terms of chromatic adaptability, between the two materials (inter-group analysis) while Kruskal–Wallis test e Two-way ANOVA statistical tests were used to evaluate the color stability of each material over time (intra-group analysis). Results: Regarding the inter-group analysis, there were no statistically significant differences between the two materials in all the comparisons: T0–T1 (p = 0.9025), T0–T2 (p = 0.2779), T0–T3 (p = 0.4694). Moreover, both groups showed an average ΔE > 2. In the intra-group analysis, no statistically significant differences were observed in either Group 1 (p = 0.954) or Group 2 (p = 0.8654). Conclusions: The in vitro color matching, assessed by spectrophotometry, of the two tested resin composites does not vary at different time intervals. Furthermore, even though both composites use different mechanisms to produce the color the human eye perceives, they show very similar chromatic adaptability.
Exploring the Impact of 3D Printing Parameters on the THz Optical Characteristics of COC Material
Authors: Kaluza Mateusz , Walczakowski Michal , Siemion Agnieszka
Published: October 2024

In terahertz (THz) optical systems, polymer-based manufacturing processes are employed to ensure product quality and the material performance necessary for proper system maintenance. Therefore, the precise manufacturing of system components, such as optical elements, is crucial for the optimal functioning of the systems. In this study, the authors investigated the impact of various 3D printing parameters using fused deposition modeling (FDM) on the optical properties of manufactured structures within the THz radiation range. The measurements were conducted on 3D printed samples using highly transparent and biocompatible cyclic olefin copolymer (COC), which may find applications in THz passive optics for “in vivo” measurements. The results of this study indicate that certain printing parameters significantly affect the optical behavior of the fabricated structures. The improperly configured printing parameters result in the worsening of THz optical properties. This is proved through a significant change in the refractive index value and undesirable increase in the absorption coefficient value. Furthermore, such misconfigurations may lead to the occurrence of defects within the printed structures. Finally, the recommended printing parameters, which improve the optical performance of the manufactured structures are presented.
Raman Spectroscopy Investigations of Ribbeck Meteorite
Authors: Dudek Mariusz , Grabarczyk Jacek , Jakubowski Tomasz , Zaręba Paweł , Karczemska Anna
Published: October 2024

On 21 January 2024, asteroid 2024BX1, discovered the three hours before, fell to Earth south of Ribbeck in the Havelland region of Germany. In this study, fragments of the Ribbeck meteorite, characterized by white and gray colors lithology, were examined for their chemical and phase compositions. The white lithology fragment exhibited a homogeneous chemical and phase structure typical of orthopyroxene, which crystallizes in the orthorhombic system. The gray lithology fragment showed a greater diversity in chemical and phase compositions. Raman spectra analysis revealed that, in addition to the pyroxenes found in the white lithology fragment, minerals from the olivine group (fayalite and forsterite) were also present, along with plagioclase and sulfur in pure crystalline form.
Molecular Dynamics, Dielectric Properties, and Textures of Protonated and Selectively Deuterated 4′-Pentyl-4-biphenylcarbonitrile Liquid Crystal
Authors: Tritt-Goc Jadwiga , Knapkiewicz Magdalena , Harmata Piotr , Herman Jakub , Bielejewski Michał
Published: October 2024

Using liquid crystals in near-infrared applications suffers from effects related to processes like parasitic absorption and high sensitivity to UV-light exposure. One way of managing these disadvantages is to use deuterated systems. The combined 1H and 2H nuclear magnetic resonance relaxometry method (FFC NMR), dielectric spectroscopy (DS), optical microscopy (POM), and differential scanning calorimetry (DSC) approach was applied to investigate the influence of selective deuteration on the molecular dynamics, thermal properties, self-organization, and electric-field responsiveness to a 4′-pentyl-4-biphenylcarbonitrile (5CB) liquid crystal. The NMR relaxation dispersion (NMRD) profiles were analyzed using theoretical models for the description of dynamics processes in different mesophases. Obtained optical textures of selectively deuterated 5CB showed the occurrence of the domain structure close to the I/N phase transition. The dielectric measurements showed a substantial difference in switching fields between fully protonated/deuterated 5CB and selectively deuterated molecules. The DSC thermograms showed a more complex phase transition sequence for partially deuterated 5CB with respect to fully protonated/deuterated molecules.
Strength and Environmental Performance Evaluation of Weathered Hydrocarbon Contaminated Soil Treated with Modified Plantain Peels—A Low Carbon Remediation Solution
Authors: Jumbo Raphael B. , Booth Colin , Abbey Samuel
Published: October 2024

This study investigated the structural and environmental recovery of weathered hydrocarbon-contaminated soils using low-carbon solutions and aimed to ascertain the suitability of the remediated soils for engineering purposes. 25% (w/w) of ground ripe (RPP) and unripe (UPP) waste plantain peels were each added to 1 kg weathered hydrocarbon-contaminated soil samples and monitored for 90 days. Biological, physicochemical, and engineering properties were analysed for all samples in triplicates. After 90 days of remediation, RPP and UPP nutrients degraded the mid-distillate hydrocarbon alkanes by 93% and 88%, while the heavier hydrocarbon alkanes were degraded by 83% and 85%, respectively. The polyaromatic hydrocarbons (PAHs) had 89% and 93% degradation for RPP and UPP-treated soils, respectively, while the natural attenuation sample had 28% degradation. The soil compressive strength increased by 16% and 19% for RPP and UPP-treated soils, respectively, whereas the natural attenuation soil compressive strength remained fairly constant. It was observed that the remediated soil cohesion, angles of internal friction, maximum dry density, and optimum moisture content all improved as the remediation proceeded, which subsequently showed that the remediation influenced the engineering properties of the contaminated soils. Therefore, the remediation of the contaminated soil improved the structural suitability of the soils.
Pt-TiO2 Systems for Enhanced Hydrogen Production from Glycerol: Direct vs Sequential Incorporation Through Photodeposition
Authors: Carozo Ana M. , López-Tenllado Francisco J. , Herrera-Beurnio M. Carmen , Hidalgo-Carrillo Jesús , Martín-Gómez Juan , Estevez Rafael , Ariza-Pérez Alejandro , Urbano Francisco J. , Marinas Alberto
Published: October 2024

Pt-TiO2 systems are the most widely used photocatalysts in the production of green hydrogen from glycerol photoreforming. To incorporate metals on the surface of materials, photodeposition is the most used method because it employs mild conditions. However, despite its use, there are some parameters that have not been deeply studied, such as the appropriate metal loading and the method itself, to obtain a better dispersion of Pt. In this work, six Pt-TiO2 catalysts were synthesized by a classical photodeposition method employing UV radiation. The studied Pt wt.% range was 0.15–0.60 wt.%, being incorporated in one step or in subsequent ones. HRTEM analyses showed that both methods allowed a homogeneous distribution of Pt, and in both, the particle size was around 2.3–3.6 nm, increasing with metal loading. The photocatalytic activity of materials was tested in glycerol photoreforming under UV radiation, and the 0.45 wt.% Pt-containing solid that had been synthesized in one step was the one that allowed the highest hydrogen production. This might suggest that around 0.40% is the appropriate metal loading for hydrogen production under these conditions and that incorporating the desired metal percentage in one step is the most efficient method in terms of energy and time savings.
Conversion of Lignin to Nitrogenous Chemicals and Functional Materials
Authors: Li Yan , Li Jingrong , Ren Bo , Cheng Haiyang
Published: October 2024

Lignin has long been regarded as waste, readily separated and discarded from the pulp and paper industry. However, as the most abundant aromatic renewable biopolymer in nature, lignin can replace petroleum resources to prepare chemicals containing benzene rings. Therefore, the high-value transformation of lignin has attracted the interest of both academia and industry. Nitrogen-containing compounds and functionalized materials are a class of compounds that have wide applications in chemistry, materials science, energy storage, and other fields. Converting lignin into nitrogenous chemicals and materials is a high-value utilization pathway. Currently, there is a large amount of literature exploring the conversion of lignin. However, a comprehensive review of the transformation of lignin to nitrogenous compounds is lacking. The research progress of lignin conversion to nitrogenous chemicals and functional materials is reviewed in this article. This article provides an overview of the chemical structure and types of industrial lignin, methods of lignin modification, as well as nitrogen-containing chemicals and functional materials prepared from various types of lignin, including their applications in wastewater treatment, slow-release fertilizer, adhesive, coating, and biomedical fields. In addition, the challenges and limitations of nitrogenous lignin-based materials encountered during the development of applications are also discussed. It is believed that this review will act as a key reference and inspiration for researchers in the biomass and material field.
Comparison of Immersion and Portable Ultrasonic Housing to Quantify the Adhesive Bond Thickness and Sizing of Foreign Objects
Authors: Blackman Nathaniel J. , Blandford Benjamin M. , Jack David A.
Published: October 2024

High-performance materials, such as carbon fiber laminates, are costly to manufacture and are often used in demanding environments requiring the use of high-resolution non-destructive testing (NDT) methods to confirm the integrity of the parts. One NDT method that has shown promise for qualifying carbon fiber laminates is the use of immersion ultrasound with spherically focused probes. However, many parts may not be submersible in an immersion tank due to size or material constraints. These parts must be scanned with contact transducers with inferior resolutions or with expensive and messy systems such as bubblers. This research presents the use of a novel housing system that allows for the use of focused immersion transducers in an out-of-tank portable ultrasonic scanning application. This work presents a comparison between scans taken using a custom high-resolution immersion system and scans taken using the presented housing. There are a wide variety of potential inspection applications for this novel system, and the present work focused on two specific applications: the quantification of the spatially varying adhesive thickness in bonded carbon fiber laminates and the quantification of foreign object inclusions in carbon fiber laminates. The results presented show that scans using the portable housing are comparable in quality to scans performed using an immersion system. Specifically, both inspection approaches had an average error of 0.04 mm when quantifying the adhesive thickness of a bonded composite, and for the foreign object detection, the error in quantifying the dimensions of the embedded foreign object was 0.1 mm and 0.2 mm for the immersion system and the portable inspection system, respectively. The demonstration was performed in a laboratory setting, but a discussion is provided for the necessary improvements needed to extend the system for use in field applications.
Effect of Microalloying Rare-Earth Nd on Microstructure Evolution and Mechanical Property of Cu Alloy
Authors: Zhang Mingyi , Yang Jichun , Huang Chongyuan , Ying Puyou , Huan Yong , Liu Fei
Published: October 2024

Cu alloys have been widely used in the manufacture of liners because of their high density, good plasticity, and excellent thermal conductivity. In order to achieve excellent jet stability and penetration performance, it is necessary to further improve the mechanical properties of Cu-based liners. Nevertheless, the simultaneous enhancement of strength and ductility of the Cu alloys remains a huge challenge due to the strength–ductility trade-off phenomenon of metals/alloys. In this study, the microstructure evolution of rare earth Nd-modified Cu alloy and its effect on mechanical properties were investigated using OM, SEM, EBSD, and TEM techniques. The results show that the ultimate tensile strength (218 MPa) and elongation (50.7%) of sample 1 without Nd are the lowest. With increasing Nd content; the tensile strength and elongation of the samples increase; and the mechanical properties of sample 4 are the best, with a tensile strength of 278.6 MPa and elongation of 65.2%. In addition, with the increase in Nd content, not only is the grain size of the Cu-Nd alloy refined, but also the strength and plasticity are improved so that the strength–ductility trade-off phenomenon is improved. The strength improvement is mainly attributed to grain refinement strengthening, dispersion strengthening, and strain hardening. The increase in ductility is mainly related to the improvement of the microstructure heterogeneity by the Nd element.
Selective Precipitation of REE-Rich Aluminum Phosphate with Low Lithium Losses from Lithium Enriched Slag Leachate
Authors: Marcinov Vladimír , Oráč Dušan , Klimko Jakub , Takáčová Zita , Pirošková Jana , Jankovský Ondřej
Published: October 2024

Currently, recycling of spent lithium-ion batteries is carried out using mechanical, pyrometallurgical and hydrometallurgical methods and their combination. The aim of this article is to study a part of the pyro-hydrometallurgical processing of spent lithium-ion batteries which includes lithium slag hydrometallurgical treatment and refining of the obtained leachate. Leaching was realized via dry digestion, which is an effective method capable of transferring over 99% of the present metals, such as Li, Al, Co, Cu, and others, to the leachate. In this work, the influence of three types of precipitation agents (NaOH, NH4OH, Na3PO4) on the precipitation efficiency of Al and Li losses was investigated. It was found that the precipitation of aluminum with NaOH can result in the co-precipitation of lithium, causing total lithium losses up to 40%. As a suitable precipitating agent for complete Al removal from Li leachate with a minimal loss of lithium (less than 2%), crystalline Na3PO4 was determined under the following conditions: pH = 3, 400 rpm, 10 min, room temperature. Analysis confirmed that, in addition to aluminum, the precipitate also contains the REEs La (3.4%), Ce (2.5%), Y (1.3%), Nd (1%), and Pr (0.3%). The selective recovery of these elements will be the subject of further study.
An Affordable Dual Purpose Spray Setup for Lithium-Ion Batteries Thin Film Electrode Deposition
Authors: Aivaliotis Dimitris , Vernardou Dimitra
Published: October 2024

This work presents a versatile and cost-effective spray setup that integrates both compressed air spray and electrospray techniques, specifically designed for small-scale laboratory use. This setup provides researchers with an accessible tool to explore spray methods for growing battery electrodes. While these techniques hold significant industrial promise, affordable and simple methods for their use in research settings have been limited. To address this, the setup includes custom control software and detailed information on costs and materials, offering an easy-to-implement solution. The system was tested with three samples per technique, using identical settings, to evaluate the repeatability of each method and gain insights into the uniformity and structure of the resulting films. The structural and morphological characteristics of the samples were analyzed using X-ray diffraction and scanning electron microscopy. The air-spray samples showed greater consistency and repeatability, whereas the electrospray samples exhibited better deposition results in terms of material coverage and higher crystallinity films. Cracking was observed in the air-spray samples, which was related to thermal stress, and both techniques exhibited solvent evaporation issues. The issues encountered with the setup and samples are summarized, along with possible solutions and the next steps for future upgrades and research.
Kinetic Study of Oxidation of Ag-Sn-Zn Solid Solution Powders via Hot Mechanochemical Processing
Authors: Guzmán Danny , Figueroa Augusto , Soliz Alvaro , Guzmán Alexis , Aguilar Claudio , Galleguillos-Madrid Felipe M. , Portillo Carlos , Shah Syed Ismat
Published: October 2024

Ag-based electrical contact materials are essential in low-voltage devices such as relays, switches, circuit breakers, and contactors. Historically, Ag-CdO composites have been preferred due to their superior electrical and thermal conductivities, resistance to arcing, and mechanical strength. However, the toxicity of Cd has led to increased restrictions on its use. With the aim of contributing to the development of a new environment-friendly, Ag-Zn2SnO4-based electrical contact material, the kinetics of the hot mechanochemical oxidation of a Ag-Sn-Zn solid solution obtained by mechanical alloying were investigated. The results indicated that the proposed synthesis route produces Ag-based composites with a homogeneous distribution of nanoscale Zn2SnO4 precipitates, which is unattainable through conventional material processing methods. This kinetic study established that the mechanochemical oxidation of the Ag-Sn-Zn solid solution follows the Johnson–Mehl–Avrami–Kolmogorov model. An analysis of the microstructure and the relationship between the activation energy “Ea” and the Avrami exponent “n” from experimental data fitting suggests that the primary mechanism for the oxidation of the Ag-Sn-Zn solid solution during the hot mechanochemical process is related to the three-dimensional oxide growth being limited by oxygen diffusion after its immediate initial nucleation.
Assessing the Effect of Specimen Preparation Methods on DSR Test Results of Bitumen Using Factorial Design Analysis
Authors: Sheidaei Maya , Zhu Jiqing , Agardh Sven
Published: October 2024

A two-level three-factor factorial design experiment was conducted to study the influences of three critical specimen preparation parameters on the measurement results of bitumen by a dynamic shear rheometer (DSR). The investigated factors were (1) the pre-heating temperature (HT) for manufacturing the specimen, (2) the bonding temperature (BT) onto the rheometer, and (3) the trimming (Trim) operation for preparing the specimen after bonding. The analysed data were the measured shear modulus |G*|, phase angle δ, and the characteristic temperatures of bitumen’s specific stiffness TX with corresponding phase angle δTX according to the European standard EN 14770:2023. Five types of bitumen were tested, including three penetration grades and two modified bitumen specimens (with polymer and wax additives). In addition, a repeatability evaluation of the test results was conducted. We found that the trimming operation for preparing the specimen has a noticeable impact when using smaller plates (PP08) for the DSR measurement. At higher test temperatures when using larger plates (PP25), the trimming operation does not significantly impact the measured parameters, in contrast to the HT and BT. Except for bitumen type 70/100, modified binders are more susceptible to variation in the analysed parameters than unmodified ones. The three-way interaction Trim:BT:HT tends to cause relatively little variation in measured data. Interactions between two factors Trim:BT, Trim:HT, and BT:HT contribute more to the fluctuation in δ value than in TX and |G*|. The variation employed in this study affects the test repeatability of wax-modified bitumen significantly; however, for unmodified binders the repeatability of TX and δTX are within 0.4–2.1 °C and 0.3–3.1°, respectively.
Friction-Induced Near-Infrared Emission and Its Mechanism
Authors: Hu Shaodong , Li Junhao , Xu Xuefeng
Published: October 2024

Triboluminescence (TL) is an optical phenomenon in which light is emitted from the surface of a material when subjected to pressure or shear forces. Due to its potential applications in non-destructive testing, radiation sources, and spectroscopic probes, TL has garnered increasing attention over the past two decades. However, experimental observations in the infrared spectrum remain limited, and its emission mechanism has not yet been fully understood. In this study, significant emission in the near-infrared spectrum was experimentally observed from the tribo-pairs of Cr/YSZ and quartz/YSZ. The results indicate that the Tribo-Induced Near-Infrared Light Emission consists of three peaks, in which the 780 nm peak is related to the electronic transition between the 3d5/2 and 3d3/2 orbitals of Y3+ ions, while the 880 nm and 990 nm peaks can be attributed to hole centers and T-type centers in the intrinsic defects of YSZ, respectively. Additionally, experiments reveal that the Cr/YSZ tribo-pair exhibits a redshift of 11–18 nm at the 780 nm peak compared to the quartz/YSZ tribo-pair. To explain the cause of the redshift phenomenon, X-ray photoelectron spectroscopy and UV-Vis absorption spectroscopy were used to measure the energy level spacing between the 3d5/2 and 3d3/2 orbitals of Y3+ and the bandgap width of YSZ before and after friction, respectively. We found that the bandgap width of the doped YSZ decreases after friction, which is often accompanied by a reduction in the energy level spacing between the 3d5/2 and 3d3/2 orbitals of Y3+. The extent of the reduction in energy level spacing varies with different dopants, leading to the redshift phenomenon.
Embedded Resistance as a Technique to Monitor Concrete Curing
Authors: Nkongolo Etienne Beya , Kevern John T.
Published: October 2024

The use of membrane-forming curing compounds on fresh concrete has been widely adopted by many States’ Departments of Transportation as it is feasible where there is a deficiency of water, on sloping surfaces where curing with water is challenging, and in cases where large areas like pavement have to be cured. However, the evaluation of the curing compound application effectiveness is difficult because most of the evaluation test methods are not performed during the early age of the concrete. Moreover, the ASTM C156 standards test of water retention for the qualification of curing compounds has met criticism as the moisture retention is performed only on the mortar specimens, with a fixed application rate and curing condition. Therefore, in this study, the embedded resistance technique was used as a test replacement for the moisture retention test to assess concrete curing. The findings from this study showed that a correlation can be found between the moisture retention test and the embedded resistance test. Based on the findings, the embedded resistance test could be a suitable replacement for the moisture loss test, because the test is much simpler and quicker to be performed both in the lab and in the field.
CsPbBr3 and Cs2AgBiBr6 Composite Thick Films with Potential Photodetector Applications
Authors: Sotelo-Lerma Merida , Fernandez-Izquierdo Leunam , Ruiz-Molina Martin A. , Borges-Doren Igor , Haroldson Ross , Quevedo-Lopez Manuel
Published: October 2024

This paper investigates the optoelectronic properties of CsPbBr3, a lead-based perovskite, and Cs2AgBiBr6, a lead-free double perovskite, in composite thick films synthesized using mechanochemical and hot press methods, with poly(butyl methacrylate) as the matrix. Comprehensive characterization was conducted, including X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), UV–visible spectroscopy (UV–Vis), and photoluminescence (PL). Results indicate that the polymer matrix does not significantly impact the crystalline structure of the perovskites but has a direct impact on the grain size and surface area, enhancing the interfacial charge transfer of the composites. Optical characterization indicates minimal changes in bandgap energies across all different phases, with CsPbBr3 exhibiting higher photocurrent than Cs2AgBiBr6. This is attributed to the CsPbBr3 superior charge carrier mobility. Both composites showed photoconductive behavior, with Cs2AgBiBr6 also demonstrating higher-energy (X-ray) photon detection. These findings highlight the potential of both materials for advanced photodetector applications, with Cs2AgBiBr6 offering an environmentally Pb-free alternative.
Application of Linear Mixed-Effects Model, Principal Component Analysis, and Clustering to Direct Energy Deposition Fabricated Parts Using FEM Simulation Data
Authors: Pazireh Syamak , Mirazimzadeh Seyedeh Elnaz , Urbanic Jill
Published: October 2024

The purpose of this study is to investigate the effects of toolpath patterns, geometry types, and layering effects on the mechanical properties of parts manufactured by direct energy deposition (DED) additive manufacturing using data analysis and machine learning methods. A total of twelve case studies were conducted, involving four distinct geometries, each paired with three different toolpath patterns based on finite element method (FEM) simulations. These simulations focused on residual stresses, strains, and maximum principal stresses at various nodes. A comprehensive analysis was performed using a linear mixed-effects (LME) model, principal component analysis (PCA), and self-organizing map (SOM) clustering. The LME model quantified the contributions of geometry, toolpath, and layer number to mechanical properties, while PCA identified key variables with high variance. SOM clustering was used to classify the data, revealing patterns related to stress and strain distributions across different geometries and toolpaths. In conclusion, LME, PCA, and SOM offer valuable insights into the final mechanical properties of DED-fabricated parts.
Nutshell Materials as a Potential Eco-Friendly Biosorbent for the Effective Extraction of UV Filters and Parabens from Water Samples
Authors: Narloch Izabela , Wejnerowska Grażyna , Kosobucki Przemysław
Published: October 2024

UV filters and parabens, as ingredients of cosmetics, are commonly occurring water pollutants. In our work, nutshells were used as biosorbents in the developed analytical procedure for the determination of UV filters and parabens in water samples. The shells obtained from walnuts, hazelnuts, peanuts and pistachios were applied as biosorbents. The proposed analytical method can be used as a powerful alternative to other methods for the analysis of UV filters and parabens in water samples. A method of carrying out the sorption step and its parameters, i.e., the effect of time, pH, and salt addition, was developed. A method for the desorption of analytes was also developed, in which the type and volume of solvent, and the desorption time, were established. The recoveries were in the range of 59–117% for benzophenones and lower recoveries from 14 to 75% for parabens. The results showed that nutshells can be used as low-cost, efficient and eco-friendly biosorbents for the determination of parabens and UV filters in water samples. These materials can be used as a ‘greener’ replacement for the commercially available adsorbents for the extraction of cosmetic ingredients from the environment.
Low-Energy Desalination Techniques, Development of Capacitive Deionization Systems, and Utilization of Activated Carbon
Authors: Elawadi Gaber A.
Published: October 2024

Water desalination technology has emerged as a critical area of research, particularly with the advent of more cost-effective alternatives to conventional methods, such as reverse osmosis and thermal evaporation. Given the vital importance of water for life and the scarcity of potable water for agriculture and livestock—especially in the Kingdom of Saudi Arabia—the capacitive deionization (CDI) method for removing salt from water has been highlighted as the most economical choice compared to other techniques. CDI applies a voltage difference across two porous electrodes to extract salt ions from saline water. This study will investigate water desalination using CDI, utilizing a compact DC power source under 5 volts and a standard current of 2 amperes. We will convert waste materials like sunflower seeds, peanut shells, and rice husks into activated carbon through carbonization and chemical activation to improve its pore structure. Critical parameters for desalination, including voltage, flow rate, and total dissolved solids (TDS) concentration, have been established. The initial TDS levels are set at 2000, 1500, 1000, and 500 ppm, with flow rates of 38.2, 16.8, and 9.5 mL/min across the different voltage settings of 2.5, 2, and 1.5 volts, applicable to both direct and inverse desalination methods. The efficiency at TDS concentrations of 2000, 1500, and 1000 ppm remains between 18% and 20% for up to 8 min. Our results indicate that the desalination process operates effectively at a TDS level of 750 ppm, achieving a maximum efficiency of 45% at a flow rate of 9.5 mL/min. At voltages of 2.5 V, 2 V, and 1.5 V, efficiencies at 3 min are attained with a constant flow rate of 9.5 mL/min and a TDS of 500 ppm, with the maximum desalination efficiency reaching 56%.
Multiscale Models of CVD Process: Review and Prospective
Authors: Tian Yu , Yan Zefan , Jiang Lin , Liu Rongzheng , Liu Bing , Shao Youlin , Yang Xu , Liu Malin
Published: October 2024

Chemical vapor deposition (CVD) is a crucial technique in the preparation of high-quality thin films and coatings, and is widely used in various industries including semiconductor, optics, and nuclear fuel, due to its operation simplicity and high growth rate. The complexity of the CVD process arises from numerous parameters, such as precursor chemistry, temperature, pressure, gas flow dynamics, and substrate characteristics. These multiscale parameters make the optimization of the CVD process a challenging task. Numerical simulations are widely used to model and analyze the CVD complex systems, and can be divided into nanoscale, mesoscale, and macroscale methods. Numerical simulation is aimed at optimizing the CVD process, but the inter-scale parameters still need to be extracted in modeling processes. However, multiscale coupling modeling becomes a powerful method to solve these challenges by providing a comprehensive framework that integrates phenomena occurring at different scales. This review presents an overview of the CVD process, the common critical parameters, and an in-depth analysis of CVD models in different scales. Then various multiscale models are discussed. This review highlights the models in different scales, integrates these models into multiscale frameworks, discusses typical multiscale coupling CVD models applied in practice, and summarizes the parameters that can transfer information between different scales. Finally, the schemes of multiscale coupling are given as a prospective view. By offering a comprehensive view of the current state of multiscale CVD models, this review aims to bridge the gap between theory and practice, and provide insights that could lead to a more efficient and precise control of the CVD process.
The Dissolution Behavior of Pyrite and Chalcopyrite During Low-Temperature Pressure Oxidation: Chalcopyrite Influence on Pyrite Oxidation
Authors: Karimov Kirill , Tretiak Maksim , Rogozhnikov Denis , Dizer Oleg
Published: October 2024

The research of this paper was carried out on the low-temperature (100 ± 2 °C) pressure (0.2–0.8 MPa) leaching of pyrite, chalcopyrite and their mixture. According to experiments on chalcopyrite dissolution, increasing the oxygen pressure from 0.2 up to 0.8 MPa had a slight effect on chalcopyrite dissolution. Oxygen pressure and initial sulfuric acid concentration in the range of 10–50 g/L had the greatest positive effect on the pyrite oxidation. The SEM and EDX mappings indicate the chalcopyrite and pyrite surfaces to be passivated by elemental sulfur. The oxidation degree of pyrite in its mixture with chalcopyrite increased significantly from 54.5 up to 80.3% in 0–240 min. The reaction time is relative to the dissolution of the individual mineral, while the dissolution of chalcopyrite remained virtually unchanged. The addition of Cu (II) and Fe (III) ions does not influence pyrite dissolution when chalcopyrite is added in a leaching process, which can be explained by the formation of an electrochemical link between the minerals. The positive effect of chalcopyrite addition is associated with a decreased formation of elemental sulfur on the surface of pyrite. The described method can be used for the hydrometallurgical processing of copper raw materials with increased pyrite content, as well as for the pretreatment of copper concentrates with gold-rich pyrite concentrates to increase the recovery of gold and silver.
Soft Matter Electrolytes: Mechanism of Ionic Conduction Compared to Liquid or Solid Electrolytes
Authors: Yasui Kyuichi , Hamamoto Koichi
Published: October 2024

Soft matter electrolytes could solve the safety problem of widely used liquid electrolytes in Li-ion batteries which are burnable upon heating. Simultaneously, they could solve the problem of poor contact between electrodes and solid electrolytes. However, the ionic conductivity of soft matter electrolytes is relatively low when mechanical properties are relatively good. In the present review, mechanisms of ionic conduction in soft matter electrolytes are discussed in order to achieve higher ionic conductivity with sufficient mechanical properties where soft matter electrolytes are defined as polymer electrolytes and polymeric or inorganic gel electrolytes. They could also be defined by Young’s modulus from about 105 Pa to 109 Pa. Many soft matter electrolytes exhibit VFT (Vogel–Fulcher–Tammann) type temperature dependence of ionic conductivity. VFT behavior is explained by the free volume model or the configurational entropy model, which is discussed in detail. Mostly, the amorphous phase of polymer is a better ionic conductor compared to the crystalline phase. There are, however, some experimental and theoretical reports that the crystalline phase is a better ionic conductor. Some methods to increase the ionic conductivity of polymer electrolytes are discussed, such as cavitation under tensile deformation and the microporous structure of polymer electrolytes, which could be explained by the conduction mechanism of soft matter electrolytes.
Role of Morphology on Zinc Oxide Nanostructures for Efficient Photoelectrochemical Activity and Hydrogen Production
Authors: Fallatah Ahmad , Kuku Mohammed , Alqahtani Laila , Bubshait Almqdad , Almutairi Noha S. , Padalkar Sonal , Alotaibi Abdullah M.
Published: October 2024

Energy generation today heavily relies on the field of photocatalysis, with many conventional energy generation strategies now superseded by the conversion of solar energy into chemical or thermal energy for a variety of energy-related applications. Global warming has pointed to the urgent necessity of moving away from non-renewable energy sources, with a resulting emphasis on creating the best photocatalysts for effective solar conversion by investigating a variety of material systems and material combinations. The present study explores the influence of morphological changes on the photoelectrochemical activity of zinc oxide nanostructures by exploiting electrodeposition and capping agents to control the growth rates of different ZnO facets and obtain well-defined nanostructures and orientations. A zinc nitrate (Zn (NO3)2) bath was used to electrodeposit ZnO nanostructures on an indium tin oxide glass (ITO) substrate at 70 °C with an applied potential of −1.0 V. Ethylenediamine (EDA) or ammonium fluoride (NH4F) were added as capping agents to the zinc nitrate bath. Extensive evaluation and characterization of the photoelectrochemical (PEC) capabilities of the resulting morphology-controlled zinc oxide nanostructures confirmed that altering the ZnO morphology can have positive impacts on PEC properties.
State of Charge Estimation for Lithium-Ion Battery Based on Fractional-Order Kreisselmeier-Type Adaptive Observer
Authors: Murakami Tomoki , Ohmori Hiromitsu
Published: October 2024

For the safe and efficient use of lithium-ion batteries, the state of charge (SOC) is a particularly important state variable. In this paper, we propose a method for the online estimation of SOC and model parameters based on a fractional-order equivalent circuit model. Firstly, we constructed a fractional-order battery model that includes pseudo-capacitance and determined the values of the circuit elements offline using the least squares method from actual input–output data based on the driving profile of an automobile. Compared to the integer-order battery model, we confirmed that the proposed fractional-order battery model has higher accuracy. Secondly, we constructed a fractional-order Kreisselmeier-type adaptive observer as an observer that performs state estimation and parameter adjustment simultaneously. Applying the general adaptive law to the battery model results in a redundant design with many adjustable parameters, so we proposed an adaptive law that reduces the number of adjustable parameters without compromising the stability of the observer. The effectiveness of the proposed method was verified through numerical simulations. As a result, the high estimation accuracy and convergence of the proposed adaptive law were confirmed.