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Ceramics International 2025年

作者： L.B. Nascimento V.G. Domiciano V.C. Pandolfelli RHI Magnesita GmbH Technology Center Leoben Austria Federal University of São Carlos Graduate Program in Materials Science and Engineering São Carlos Brazil RHI Magnesita Research and Development Center Contagem Brazil

Calcium aluminate cement (CAC) is broadly used in refractory compositions due to its advantages, although CaO can affect the castable’s hot properties when silica is present. The need for higher-temperature applications and tougher conditions has led to innovations in high-performance materials, focusing on reducing CAC content and using binders without CaO or SiO 2 . Although progress has been made in their application, these binders still have limitations. Colloidal alumina is particularly promising for generating a silica-free system with higher refractoriness and lower liquid phase formation, depending on the refractory composition. Based on these aspects, this work evaluated the influence of using colloidal alumina as a binder in refractory castables (Al 2 O 3 -SiC-C) for blast furnace main troughs, comparing its properties to a commercially available silica sol castable. The influence of different dispersants, gelling agents and secondary binders on the properties of both sol-bonded castables was investigated. The results indicated that citric acid was the most effective dispersant in providing suitable rheological behavior based on its interaction with alumina particles (electrostatic mechanism), magnesia sinter and calcium aluminate cement. Furthermore, using optimized amounts of citric acid, MgO and CAC, a colloidal alumina-bonded refractory composition with higher green mechanical strength and suitable working time was obtained compared to the colloidal silica castable used as reference.

关键词： Magnesia refractories

Unravelling Exothermic Reaction Dynamics in Polyurethane Polymerization: A Thermo-Kinetic Simulation Approach

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SSRN

SSRN 2023年

作者： Mendija, Leanne Christie C. Dingcong, Roger G. Alfeche, Fortia Louise Adeliene M. Al-Moameri, Harith H. Dumancas, Gerard G. Malaluan, Roberto M. Alguno, Arnold C. Lubguban, Arnold A. Center for Sustainable Polymers Mindanao State University Iligan Institute of Technology Iligan City9200 Philippines Material Science and Engineering Program Graduate School of Engineering Mindanao State University Iligan Institute of Technology Iligan City9200 Philippines Department of Materials Engineering Mustansiriyah University Baghdad10052 Iraq Department of Chemistry The University of Scranton ScrantonPA18510 United States Department of Chemical Engineering and Technology Mindanao State University Iligan Institute of Technology Iligan City9200 Philippines Department of Physics Mindanao State University Iligan Institute of Technology Iligan City9200 Philippines

The pursuit of sustainable polyurethane product development necessitates a profound understanding of precursor materials, particularly polyol since polyurethane properties are heavily influenced by the type of polyol employed during polyurethane production. While traditional polyurethanes are solely derived from hydroxyl functionalized polyols, the emergence of amine-hydroxyl hybrid polyols has garnered significant attention due to their potential for enhancing polyurethane product properties. These hybrid polyols are characterized by the presence of both amine and hydroxyl functional groups. However, characterizing these polyols remains a daunting challenge due to the lack of established experimental testing standards for properties, such as fractional hydroxyl and amine moieties, and thermo-kinetic parameters for amine reactions with isocyanates. To bridge these gaps, this study employed a computational simulation approach to determine the fractions of moieties in both traditional and hybrid polyols. Additionally, this study determined the thermo-kinetic parameters for exothermic isocyanate reactions with amine moieties in hybrid polyols. The computational method integrated energy balance and reaction kinetics analysis for various polyols to elucidate the influence of functional moieties on the thermo-kinetic behavior of polyurethane formations. Validation of the simulated results was conducted by comparing their experimental and simulated gel and foam temperature profiles, highlighting the direct influence of fractional moieties on polyurethane formations. The comparisons revealed an average relative error of less than 5%, indicating the accuracy and credibility of the simulation. Thus, this study represents a pivotal opportunity for advancing knowledge and driving sustainable developments in biobased polyol characterization for polyurethane production streamlining and formulation optimization. © 2023, The Authors. All rights reserved.

关键词： Polymerization

A comparative study of the structural and optoelectronic properties of Al- and Ga-doped ZnO films deposited by atmospheric pressure plasma jet

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Journal of Alloys and Compounds 2025年 1031卷

作者： Chou, Chih-Yun Chiu, Po-Han Chao, Yin-Chun Yen, Hung-Wei Juang, Jia-Yang Program in Nanoengineering and Nanoscience Graduate School of Advanced Technology National Taiwan University Taipei106319 Taiwan Department of Materials Science and Engineering National Taiwan University Taipei106319 Taiwan Department of Mechanical Engineering National Taiwan University Taipei106319 Taiwan

The high cost of gallium has driven interest in aluminum-doped zinc oxide (AZO) as a cost-effective alternative to gallium-doped zinc oxide (GZO). While prior studies have primarily focused on sputtering methods to compare AZO and GZO, research on non-sputtering techniques remains limited. Our previous works demonstrated favorable optoelectronic properties in GZO films deposited via atmospheric pressure plasma jet (APPJ);however, APPJ-deposited AZO has yet to be explored. In this study, we compare AZO and GZO thin films fabricated by APPJ under ambient conditions. We find that the deposition rate of AZO is approximately twice that of GZO under the same processing parameters, due to differences in droplet size from the ultrasonic generator. By adjusting precursor delivery and working distance (the nozzle-to-substrate gap), we can tune film thickness, morphology, and optoelectronic properties, showcasing APPJ's versatility over sputtering. Despite similar precursor concentrations and film thickness, AZO films exhibit lower carrier concentration (∼1 ×1020 cm–3) and mobility (∼7.5 cm2/Vs) than GZO (∼8 ×1020 cm–3 and ∼15 cm²/Vs), attributed to reduced aluminum incorporation (∼0.4 at% vs. ∼2.2 at% in GZO). Reducing the working distance from 2 mm to 1.5 mm improves both films’ structural integrity and optoelectronic performance (figure of merit increases by 140 % for GZO and 100 % for AZO). However, AZO remains inferior to GZO, highlighting the need for further optimization. © 2025 Elsevier B.V.

关键词： Transparent conducting oxides

Two-dimensional perovskites with maximum symmetry enable exciton diffusion length exceeding 2 micrometers

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arXiv 2025年

作者： Hou, Jin Fletcher, Jared Hall, Siedah J. Zhang, Hao Zacharias, Marios Volonakis, George Welton, Claire Mandani, Faiz Metcalf, Isaac Sun, Shuo Zhang, Bo Guo, Yinsheng Reddy, G.N. Manjunatha Katan, Claudine Even, Jacky Sfeir, Matthew Y. Kanatzidis, Mercouri G. Mohite, Aditya D. Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States Department of Chemistry Department of Materials Science and Engineering Northwestern University EvanstonIL60208 United States Photonics Initiative Advanced Science Research Center City University of New York New York10031 United States Department of Physics The Graduate Center City University of New York New York10016 United States Department of Chemical and Biomolecular Engineering Rice University HoustonTX77005 United States Applied Physics Graduate Program Smalley‐Curl Institute Rice University HoustonTX77005 United States Univ Rennes INSA Rennes CNRS Institut FOTON UMR 6082 Rennes35708 France UMR 6226 RennesF-35000 France University of Lille CNRS Centrale Lille Institute Univ. Artois UMR 8181−UCCS− Unité de Catalyse et Chimie du Solide LilleF-59000 France Department of Chemistry University of Nebraska-Lincoln LincolnNE68588 United States

Realizing semiconductors with high symmetry of their crystallographic structures has been a virtue of inorganic materials and has resulted in novel physical behaviors. In contrast, hybrid (organic and inorganic) crystals such as two-dimensional metal halide perovskites exhibit much lower crystal symmetry due to in-plane or out-of-plane octahedral distortions. Despite their amazing ability for photoinduced light emission at room temperature, the Achilles' heel of this attractive class of 2D materials for optoelectronics remains the poor control and lack of performance for charge carrier transport. Inspired by the tremendous charge carrier properties of the 3D cubic perovskite phase (α) of FAPbI3 and combining the use of the appropriate cage cation, the spacer molecule and the temperature and rate of crystallization, we report a new series of FA-based layered two-dimensional perovskites that exhibits the highest theoretically predicted symmetry with a tetragonal P4/mmm space group, resulting in no octahedral distortion in both in-plane and out-of-plane directions. These 2D perovskites present the shortest interlayer distances (4 Å), which results in systematically lower bandgaps (1.7 to 1.8 eV). Finally, the absence of octahedral distortions, results in an exciton diffusion length of 2.5 µm, and a diffusivity of 4.4 cm2s-1, both of which are an order of magnitude larger compared to previously reported 2D perovskites and on par with monolayer transition metal dichalcogenides. © 2025, CC BY.

关键词： Charge carriers

Braiding fractional quantum Hall quasiholes on a superconducting quantum processor

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arXiv 2023年

作者： Kirmani, Ammar Wang, Derek S. Ghaemi, Pouyan Rahmani, Armin Physics Department City College of the City University of New York NY10031 United States IBM Quantum IBM T.J. Watson Research Center Yorktown Heights10598 United States Physics Program Graduate Center of City University of New York NY10031 United States Department of Physics and Astronomy and Advanced Materials Science and Engineering Center Western Washington University BellinghamWA98225 United States

Direct experimental detection of anyonic exchange statistics in fractional quantum Hall systems by braiding the excitations and measuring the wave-function phase is an enormous challenge. Here, we use a small, noisy quantum computer to emulate direct braiding within the framework of a simplified model applicable to a thin cylinder geometry and measure the topological phase. Our algorithm first prepares the ground state with two quasiholes. It then applies a unitary operation controlled by an ancilla, corresponding to a sequence of adiabatic evolutions that take one quasihole around the other. We finally extract the phase of the wave function from measuring the ancilla with a compound error mitigation strategy. Our results open a new avenue for studying braiding statistics in fractional Hall states. Copyright © 2023, The Authors. All rights reserved.

关键词： Wave functions

Effect of Heat Treatment Duration on the Recrystallization and Electrochemical Properties of Cold-Rolled Cantor-Type High-Entropy Alloy

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materials (Basel, Switzerland) 2025年第10期18卷 2298页

作者： Byung-Hyun Shin Jinsurang Lim Doo-In Kim Jung-Woo Ok Seongjun Kim Jinyong Park Jonggi Hong Taekyu Lee Jang-Hee Yoon Je In Lee Yeongnam Regional Center Korea Basic Science Institute Busan 46742 Republic of Korea. School of Materials Science and Engineering Pusan National University Busan 46742 Republic of Korea. Innovative Graduate Education Program for Global High-Tech Materials and Parts Pusan National University Busan 46241 Republic of Korea.

High-entropy alloys (HEAs), such as the Cantor alloy, are considered for various structural applications owing to their excellent corrosion resistance and high strength at low temperatures, typically below -70 °C, including cryogenic conditions. However, during metalworking, introducing stresses and grain refinement can reduce the corrosion resistance of HEAs. Recrystallization heat treatment relieves these stresses and homogenizes the grain structure, thereby restoring their corrosion resistance and physical properties. However, inadequate heat treatment can result in a microstructure in which coarse and refined grains coexist; thus, the corrosion resistance is diminished and the physical properties are compromised. Therefore, a proper heat treatment is essential for achieving the desired corrosion resistance and mechanical properties of HEAs. In this study, a cold-rolled high-entropy Cantor alloy was subjected to heat treatment for various durations, and the conditions were analyzed. The microstructure and electrochemical behavior were examined. The results indicated that the grains coarsened after a heat treatment time of 5 min and the residual stresses decreased for 15 min. The potential increased from -0.20 to -0.09 V, whereas the resistance of the passive layer increased from 39 to 56 kΩ. These findings confirm that in the Cantor alloy, residual stress reduction and recrystallization begin after 5 min of heat treatment at 1100 °C, which contributes to the recovery of corrosion resistance. The corrosion resistance of the Cantor alloy can be effectively controlled through heat treatment. This underscores the importance of optimizing the heat treatment process in the manufacturing of Cantor alloys.

关键词： electrochemical behavior heat treatment time high-entropy alloy microstructure residual stress

Non-linear optics at twist interfaces in h-BN/SiC heterostructures

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arXiv 2023年

作者： Biswas, Abhijit Xu, Rui Alvarez, Gustavo A. Zhang, Jin Christiansen-Salameh, Joyce Puthirath, Anand B. Burns, Kory Hachtel, Jordan A. Li, Tao Iyengar, Sathvik Ajay Gray, Tia Li, Chenxi Zhang, Xiang Kannan, Harikishan Elkins, Jacob Pieshkov, Tymofii S. Vajtai, Robert Birdwell, A. Glen Neupane, Mahesh R. Garratt, Elias J. Ivanov, Tony Pate, Bradford B. Zhao, Yuji Zhu, Hanyu Tian, Zhiting Rubio, Angel Ajayan, Pulickel M. Department of Materials Science and Nanoengineering Rice University HoustonTX77005 United States Sibley School of Mechanical and Aerospace Engineering Cornell University IthacaNY14853 United States Max Planck Institute for the Structure and Dynamics of Matter Center for Free-Electron Laser Science Luruper Chaussee 149 22761 Germany Department of Materials Science & Engineering University of Virginia CharlottesvilleVA22904 United States Center for Nanophase Materials Sciences Oak Ridge National Laboratory Oak RidgeTN37831 United States Department of Electrical and Computer Engineering Rice University HoustonTX77005 United States DEVCOM Army Research Laboratory RF Devices and Circuits AdelphiMD20783 United States Chemistry Division Naval Research Laboratory WashingtonDC20375 United States Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States Flatiron Institute New YorkNY10010 United States

Understanding the emergent electronic structure in twisted atomically thin layers has led to the exciting field of twistronics. However, practical applications of such systems are challenging since the specific angular correlations between the layers must be precisely controlled and the layers have to be single crystalline with uniform atomic ordering. Here, we suggest an alternative, simple and scalable approach where nanocrystalline two-dimensional (2D) film on three-dimensional (3D) substrates yield twisted-interface-dependent properties. Ultrawidebandgap hexagonal boron nitride (h-BN) thin films are directly grown on high in-plane lattice mismatched wide-bandgap silicon carbide (4H-SiC) substrates to explore the twist-dependent structure-property correlations. Concurrently, nanocrystalline h-BN thin film shows strong nonlinear second-harmonic generation and ultra-low cross-plane thermal conductivity at room temperature, which are attributed to the twisted domain edges between van der Waals stacked nanocrystals with random in-plane orientations. First-principles calculations based on time-dependent density functional theory manifest strong even-order optical nonlinearity in twisted h-BN layers. Our work unveils that directly deposited 2D nanocrystalline thin film on 3D substrates could provide easily accessible twist-interfaces, therefore enabling a simple and scalable approach to utilize the 2D-twistronics integrated in 3D material devices for next-generation nanotechnology. © 2023, CC BY.

关键词： Harmonic generation

Cover Feature: Mechanical Bond Induced Enhancement and Purification of Pyrene Emission in the Solid State (Chem. Eur. J. 42/2024)

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Chemistry – A European Journal 2024年第42期30卷

作者： Shu Zhang Ru Zhou Ningjin Zhang Yi An Zhiyang Liu Xu-Man Chen Quan Li Institute of Advanced Materials and School of Chemistry and Chemical Engineering Southeast University Nanjing 211189 China Instrumental Analytical Centre Shanghai Jiao Tong University Shanghai 201100 China Materials Science Graduate Program Kent State University Kent OH 44242 USA

Unraveling the bioenergy production and electron transport characteristics of processed Rheum palmatum L. for antiviral drug development

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Industrial Crops and Products 2023年第1期195卷

作者： Tsai, Po-Wei Hsieh, Cheng-Yang Ting, Jasmine U. Rogio, Kristian Gil G. Lee, Chia-Jung De Castro-Cruz, Kathlia A. Ciou, Yi-Ru Lien, Tzu-Kuan Yang, Ling-Ling Hsueh, Chung-Chuan Chen, Bor-Yann Department of Medical Science Industries College of Health Sciences Chang Jung Christian University Tainan711 Taiwan Ph.D. Program in Clinical Drug Development of Herbal Medicine College of Pharmacy Taipei Medical University Taipei110 Taiwan Department of Chemistry College of Science De La Salle University Metro Manila1004 Philippines School of Chemical Biological and Materials Engineering and Sciences Mapúa University Metro Manila1002 Philippines Graduate Institute of Pharmacognosy College of Pharmacy Taipei Medical University Taipei110 Taiwan Traditional Herbal Medicine Research Center Taipei Medical University Hospital Taipei110 Taiwan Department of Chemical and Materials Engineering National I-Lan University I-Lan260 Taiwan American College of Acupuncture & Oriental Medicine HoustonTX77063 United States

To bridge western and traditional Chinese medicine, research in Chinese medicinal herbs has become an increasing trend for discovering new effective antiviral drugs. In addition, this pioneer study disclosed that synergistic interactions of electron-mediating contents in herbal medicines through electrochemical catalysis of electron shuttles could trigger effective disease treatment via electron transport stimulation as the platform of microbial fuel cells (MFCs) indicated. Hence, this study first attempted to decipher the bioenergy-assisted action of R. palmatum L. for antiviral assessment. Several processing methods can be performed to maximize phytoconstituent extraction and efficiency that can influence the chemical profile and bioactivity of herbal samples. To generate a comparative analysis, R. palmatum L. roots are subjected to several processing methods and are evaluated through phytochemical screening, antioxidant activity, high-performance liquid chromatography analysis, and dual-chambered-MFCs for bioenergy production. Molecular docking analysis of marker substances was also employed to establish the potential of R. palmatum L. for antiviral drug development. Ethanol extracts are revealed to be toxic for MFCs despite having increased phenolic compounds. Overall, vinegar-processed Rheum palmatum water extracts exhibited the highest bioenergy-stimulating capabilities and antioxidant activity. Furthermore, rhein from the same extract was found to exhibit strong binding affinities towards Flaviviridate viruses and can potentially inhibit NS5B polymerase from the Hepatitis C Virus. This study clearly suggests the potential of R. palmatum L. roots as a promising herb for antiviral drug development. This work also provided a novel protocol for prescreening candidate species for antiviral drug development. © 2023 Elsevier B.V.

关键词： Extraction

Magnetism and magnetocaloric properties of Co1−xMnxCr2O4

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arXiv 2023年

作者： Cooley, Joya A. Dairaghi, Gregor Moore, Guy C. Horton, Matthew K. Schueller, Emily C. Persson, Kristin A. Seshadri, Ram Department of Chemistry and Biochemistry California State University FullertonCA92834 United States Department of Physics Carleton College NorthfieldMN55057 United States Applied Physics Graduate Program Northwestern University EvanstonIL60208 United States Department of Materials Science and Engineering University of California Berkeley BerkeleyCA94720 United States Materials Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Materials Research Laboratory University of California Santa BarbaraCA93106 United States Materials Department University of California Santa BarbaraCA93106 United States Molecular Foundry Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Department of Chemistry and Biochemistry University of California Santa BarbaraCA93106 United States

Co1−xMnxCr2O4 crystallizes as a normal spinel in the cubic Fd3m space group, and the end members have been reported to display a region of collinear ferrimagnetism as well as a low-temperature spin-spiral state with variable coherence lengths from 3 nm to 10 nm in polycrystalline samples. Here, we present the synthesis of the entire solid solution, and data showing that the ferrimagnetic ordering temperature as well as the spin-spiral lock-in temperature are tunable with the Co/Mn ratio. The peak magnetocaloric entropy change was determined to be ∆SM = −5.63 J kg −1K −1 in an applied magnetic field change of ∆H = 0 T to 5 T for the Mn end-member at the ferrimagnetic ordering temperature. Using density functional theory (DFT), we explore the shortcomings of the magnetic deformation proxy to identify trends in ∆SM across composition in this spinel system, and explore future extensions of theory to address these discrepancies. Copyright © 2023, The Authors. All rights reserved.

关键词： Temperature