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Utilization of ornamental rock waste as a catalytic support for α-MoO₃ in biodiesel production

Scientific Reports 2025年第1期15卷 1-24页

作者： Sales, H.B. Oliveira, M.S. Silva, A.L. Pereira, H.L. Costa, A.C.F.M. Alves, M.C.F. Laboratory of Ceramic Materials Synthesis (LabSMac) Graduate Program in Materials Science and Engineering (PPGCEMat) Academic Unit of Materials Engineering (UAEMa) Federal University of Campina Grande (UFCG) Rua Aprígio Veloso 882 Bodocongó 58.429-900 PB Campina Grande Brazil Laboratory of Inorganic Materials for Environmental Catalysis Research Department of Chemistry (MATIPECA) Graduate Program in Chemistry (PPGQ) DQ State University of Paraíba (UEPB) Rua Baraúnas 351 Universitário 58.429-500 PB Campina Grande Brazil

This study aimed to explore the use of ornamental stone waste as a support for the α-MoO₃ catalyst to develop efficient and sustainable heterogeneous systems for biodiesel production. The catalysts were characterized using physicochemical techniques including X-ray diffraction with Rietveld refinement, FTIR and Raman spectroscopy, scanning electron microscopy with EDS, transmission electron microscopy, nitrogen adsorption/desorption (BET method), particle size distribution, ammonia temperature-programmed desorption (TPD-NH₃), magnetic measurements, and gas chromatography to analyze simultaneous transesterification/esterification (TES) reactions and quantify methyl and ethyl esters. XRD patterns revealed crystalline phases such as mica-biotite, ferro-tschermakite, albite, quartz, and iron-magnesium silicates—components of the catalytic support—as well as orthorhombic α-MoO₃ phases, also confirmed in the heterogeneous systems. FTIR and Raman analyses showed characteristic vibrational bands, while SEM images displayed irregular agglomerates, corroborated by TEM. Nitrogen adsorption isotherms indicated mesoporous structures with surface areas ranging from 0.615 to 3.87 m²/g. Particle size analysis showed D₅₀ values between 5.02 and 20.00 μm, with total acidity ranging from 77.0 to 245 µmol/g of NH₃. Magnetic tests indicated ferrimagnetic behavior. The catalytic performance confirmed the effectiveness of the waste as a support for α-MoO₃, particularly in the system containing 40% Mo ions (40%σ-MoO₃:Waste), which achieved conversions between 78% and 95%. These findings highlight the environmental and technological potential of the studied catalysts, reinforcing the economic viability and ecological relevance of reusing industrial waste in the sustainable production of biodiesel from waste oils. © The Author(s) 2025.

关键词： And sustainability Green technology Heterogeneous catalysis Industrial waste MoO₃ Waste oils

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Investigating the impact of metal ion variations in terephthalate metal–organic frameworks on the organic solvent nanofiltration performance of mixed matrix membranes

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Journal of Membrane science 2024年 700卷

作者： Ajebe, Eyasu Gebrie Hu, Chien Chieh Lugito, Graecia Hu, Chun-Po Hung, Wei-Song Lee, Kueir-Rarn Lai, Juin-Yih Graduate Institute of Applied Science and Technology Advanced Membrane Materials Research Center National Taiwan University of Science and Technology Taipei Taiwan Chemical Engineering Study Program Faculty of Industrial Technology Institut Teknologi Bandung West Java Indonesia Nanyang Technological University 1 Cleantech Loop Singapore R&D Center for Membrane Technology Chung Yuan University Chungli Taoyuan Taiwan Department of Chemical Engineering and Materials Science Yuan Ze University Chungli Taoyuan Taiwan

Nano-fillers integrated into mixed matrix membranes (MMMs) present promising alternatives for organic solvent nanofiltration (OSN). In this work, our objective is to enhance OSN performance by incorporating terephthalate metal-organic frameworks (M-BDC, where M = Zr or Cu) into a P84 matrix to fabricate M-BDC/P84 composite MMMs. This work focuses on the influence of metal cluster variation on particle size, pore size distribution, and specific surface area of M-BDC, while systematically investigating the impact of M-BDC addition on OSN performance and underlying separation mechanisms. The synthesized membranes underwent comprehensive characterization using SEM, XRD, ATR-FTIR, contact angle, zeta potential, and thermogravimetric analysis. Significantly, all MMMs exhibited superior permeance and methyl blue (MB) rejection compared to P84 membranes. This enhancement is attributed to the improved interfacial contact between M-BDC and P84, as well as their effective dispersion within the membrane matrix. Interestingly, comparative analysis between Cu-BDC/P84 and Zr-BDC/P84 MMMs revealed the latter's superior permeance, attributed to its larger pore size and surface area. The resulting MMMs demonstrated outstanding MB rejection (>96.7%) with ethanol permeance of 21.5 and 19.0 LMH/Bar for Zr-BDC/P84 and Cu-BDC/P84 MMMs, respectively. Furthermore, the stable performance of M-BDC-based MMMs during prolonged MB/ethanol operation underscores their potential significance in the field of OSN, providing valuable insights for future membrane design and application. © 2024 Elsevier B.V.

关键词： Organometallics

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Plasmonic Nanolaser by Silver Nanowire Embedded in CsPbBr3 Quantum Dots

Plasmonic Nanolaser by Silver Nanowire Embedded in CsPbBr3 Q...

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JSAP-OSA Joint Symposia, JSAP 2021

作者： Xing, Di Lin, Cheng-Chieh Won, Phillip Xiang, Rong Chen, Tzu-Pei A. Kamal, A. Syazwan Lee, Yang-Chun Ho, Ya-Lun Maruyama, Shigeo Ko, Seung Hwan Chen, Chun-Wei Delaunay, Jean-Jacques School of Engineering The University of Tokyo Japan International Graduate Program of Molecular Science and Technology National Taiwan University Taiwan Department of Materials Science and Engineering National Taiwan University Taiwan Department of Mechanical Engineering Seoul National University Korea Republic of Center of Atomic Initiative for New Materials National Taiwan University Taiwan

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Reliable operation of Cr2O3:Mg/β-Ga2O3 p-n heterojunction diodes at 600◦C

arXiv

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arXiv 2024年

作者： Callahan, William A. Egbo, Kingsley Lee, Cheng-Wei Ginley, David O'Hayre, Ryan Zakutayev, Andriy Materials Science Center National Renewable Energy Laboratory GoldenCO80401 United States Advanced Energy Systems Graduate Program Colorado School of Mines GoldenCO80401 United States Department of Metallurgical and Materials Engineering Colorado School of Mines GoldenCO80401 United States

β-Ga2O3-based semiconductor heterojunctions have recently demonstrated improved performance at high voltages and elevated temperatures and are thus promising for applications in power electronic devices and harsh-environment sensors. However, the long-term reliability of these ultra-wide band gap (UWBG) semiconductor devices remains barely addressed and may be strongly influenced by chemical reactions at the p-n heterojunction interface. Here, we experimentally demonstrate operation and evaluate the reliability of Cr2O3:Mg/β-Ga2O3 p-n heterojunction diodes at during extended operation at 600◦C, as well as after 30 repeated cycles between 25-550◦C. The calculated pO3-temperature phase stability diagram of the Ga-Cr-O material system predicts that Ga2O3 and Cr2O3 should remain thermodynamically stable in contact with each other over a wide range of oxygen pressures and operating temperatures. The fabricated Cr2O3:Mg/β-Ga2O3 p-n heterojunction diodes show room-temperature on/off ratios >104 at ±5V and a breakdown voltage (VBr) of -390V. The leakage current increases with increasing temperature up to 600◦C, which is attributed to Poole-Frenkel emission with a trap barrier height of 0.19 eV. Over the course of a 140-hour thermal soak at 600◦C, both the device turn-on voltage and on-state resistance increase from 1.08V and 5.34 mΩ-cm2 to 1.59V and 7.1 mΩ-cm2 respectively. This increase is attributed to the accumulation of Mg and MgO at the Cr2O3/Ga2O3 interface as observed from TOF-SIMS analysis. These findings inform future design strategies of UWBG semiconductor devices for harsh environment operation and underscore the need for further reliability assessments for β-Ga2O3 based devices. © 2024, CC BY.

关键词： Gallium compounds

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Empowering Machines to Think Like Chemists: Unveiling Molecular Structure-Polarity Relationships with Hierarchical Symbolic Regression

arXiv

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arXiv 2024年

作者： Lou, Siyu Liu, Chengchun Chen, Yuntian Mo, Fanyang Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai200240 China Ningbo Institute of Digital Twin Eastern Institute of Technology Ningbo315200 China School of Materials Science and Engineering Peking University Beijing100871 China -Preferred Program Peking University Shenzhen Graduate School Shenzhen518500 China

Thin-layer chromatography (TLC) is a crucial technique in molecular polarity analysis. Despite its importance, the interpretability of predictive models for TLC, especially those driven by artificial intelligence, remains a challenge. Current approaches, utilizing either high-dimensional molecular fingerprints or domain-knowledge-driven feature engineering, often face a dilemma between expressiveness and interpretability. To bridge this gap, we introduce Unsupervised Hierarchical Symbolic Regression (UHiSR), combining hierarchical neural networks and symbolic regression. UHiSR automatically distills chemical-intuitive polarity indices, and discovers interpretable equations that link molecular structure to chromatographic behavior. Copyright © 2024, The Authors. All rights reserved.

关键词： Thin layer chromatography

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Effects of nanopores and sulfur doping on hierarchically bunched carbon fibers to protect lithium metal anode

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Carbon Energy 2021年第5期3卷 784-794页

作者： Ji In Jung Sunwoo Park Son Ha Se Youn Cho Hyoung-Joon Jin Young Soo Yun Program in Environmental and Polymer Engineering Inha UniversityIncheonSouth Korea KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoulSouth Korea Carbon Composite Materials Research Center Korea Institute of Science and TechnologyWanju-gunJeollabuk-doSouth Korea Department of Polymer Science and Engineering Inha UniversityIncheonSouth Korea Department of Integrative Energy Engineering Korea UniversitySeoulSouth Korea

Studies on three-dimensional structured carbon templates have focused on how to guide homogeneous lithium metal nucleation and growth for lithium metal anodes(LMAs).However,there is still insufficient evidence for a key factor to achieve their high electrochemical ***,the effects of nanopores and sulfur doping on carbon-based nanoporous host(CNH)electrode materials for LMAs were investigated using natural polymer-derived *** pore-filling behaviors of lithium metal in the nanopores of the CNH electrode materials were first observed by ex situ scanning electron microscopy analysis,where the protective lithium metal nucleation and growth process led to significantly high Coulombic efficiency(CE)of~99.4%and stable 600 *** addition,a comparison study of CNH and sulfurdoped CNH(S-CNH)electrodes,which differ only in the presence or absence of sulfur,revealed that sulfur doping can cause lower electrochemical series resistance,higher CE value,and better cycling stability in a wide range of current densities and number of ***,S-CNH-based LMAs showed high electrochemical performance in full-cell Li-S battery tests using a sulfur copolymer cathode,where a high energy density of 1370Wh kgelectrode−1 and an excellent power density of 4120Wkgelectrode−1 were obtained.

关键词： carbon template Li-S batteries lithium metal anode lithium metal batteries nanoporous carbon sulfur doping

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Revisiting the Assessment of Magnetic Texture of Magnets: The Role of Coercivity

SSRN

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SSRN 2024年

作者： Quispe, Luis T. Antunes, Leonardo F. Baldárrago-Alcántara, Apuniano A. Macedo, Wagner C. Rosa, Marcelo Augusto Rebelo, Querem H.F. Lopes, Leonardo U. Souza, Sérgio Michielon Wendhausen, Paulo Antônio Pereira Magnetic Materials Laboratory MAGMA Federal University of Santa Catarina Florianopolis88040-900 Brazil Graduate Program in Materials Science and Engineering PGMAT Federal University of Santa Catarina Florianopolis88040-900 Brazil Institute of Engineering and Geosciences Federal University of Western Pará Pará Santarém68035-110 Brazil Department of Materials Physics Federal University of Manaus Manaus69077-000 Brazil

A crucial figure of merit of magnets is their magnetic texture, because it is closely related to the maximum remanence a magnet can achieve, hence assessing the magnetic texture is pivotal in terms of magnet’s performance. Fernengel et al. (1996) developed a methodology based on magnetometry, which allows for a quick determination of the texture by calculating the degree of alignment 〈cosθ〉 from the remanent magnetization in directions parallel and perpendicular to the texture axis of the magnet. Although this method provided reliable values, its application was limited to magnets with high degrees of alignment (〈cosθ〉 > 95%), a restriction that was corrected by Quispe et al. (2020). Nevertheless, recent experiments have indicated that the magnetometry technique can introduce errors in texture assessment when the magnet presents high levels of coercivity. This work presents an approach that incorporates a correction factor into the magnetometry technique, accounting for the effect of the coercivity and circumventing this error source in texture assessment. The proposed methodology has been successfully applied to magnets with varying levels of coercivity. © 2024, The Authors. All rights reserved.

关键词： Coercive force

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Thickness, Annealing, and Surface Roughness Effect on Magnetic and Significant Properties of Co40Fe40B10Dy10 Thin Films

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materials 2023年第17期16卷 5995页

作者： Liu, Wen-Jen Chang, Yung-Huang Chiang, Chia-Chin Chen, Yuan-Tsung Wang, Yu-Zhi Wu, Chueh-Lin Lin, Shih-Hung Ou, Sin-Liang Department of Materials Science and Engineering I-Shou University Kaohsiung84001 Taiwan Bachelor Program in Industrial Technology National Yunlin University of Science and Technology 123 University Road Section 3 Douliou64002 Taiwan Department of Mechanical Engineering National Kaohsiung University of Science and Technology Kaohsiung80778 Taiwan Graduate School of Materials Science National Yunlin University of Science and Technology 123 University Road Section 3 Douliou64002 Taiwan Department of Electronic Engineering National Yunlin University of Science and Technology 123 University Road Section 3 Douliou64002 Taiwan Bachelor Program for Design and Materials for Medical Equipment and Devices Da-Yeh University Changhua51591 Taiwan

In this study, Co40Fe40B10Dy10 thin films were deposited using a direct current (DC) magnetron sputtering technique. The films were deposited on glass substrates with thicknesses of 10, 20, 30, 40, and 50 nm, and heat-treated in a vacuum annealing furnace at 100, 200, and 300 °C. Various instruments were used to examine and analyze the effects of roughness on the magnetic, adhesive, and mechanical properties. From the low frequency alternating current magnetic susceptibility (χac) results, the optimum resonance frequency is 50 Hz, and the maximum χac value tends to increase with the increase in the thicknesses and annealing temperatures. The maximum χac value is 0.18 at a film thickness of 50 nm and an annealing temperature of 300 °C. From the four-point probe, it is found that the resistivity and sheet resistance values decrease with the increase in film deposition thicknesses and higher annealing temperatures. From the magnetic force microscopy (MFM), the stripe-like magnetic domain distribution is more obvious with the increase in annealing temperature. According to the contact angle data, at the same annealing temperature, the contact angle decreases as the thickness increases due to changes in surface morphology. The maximal surface energy value at 300 °C is 34.71 mJ/mm2. The transmittance decreases with increasing film thickness, while the absorption intensity is inversely proportional to the transmittance, implying that the thickness effect suppresses the photon signal. Smoother roughness has less domain pinning, more carrier conductivity, and less light scattering, resulting in superior magnetic, electrical, adhesive, and optical performance. © 2023 by the authors.

关键词： Thin films

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Connecting polymer collapse and the onset of jamming

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Physical Review E 2024年第3期109卷 034406-034406页

作者： Alex T. Grigas Aliza Fisher Mark D. Shattuck Corey S. O'Hern Graduate Program in Computational Biology and Bioinformatics Yale University New Haven Connecticut 06520 USA Integrated Graduate Program in Physical and Engineering Biology Yale University New Haven Connecticut 06520 USA Department of Mechanical Engineering and Materials Science Yale University New Haven Connecticut 06520 USA Benjamin Levich Institute and Physics Department The City College of New York New York New York 10031 USA Department of Physics Yale University New Haven Connecticut 06520 USA Department of Applied Physics Yale University New Haven Connecticut 06520 USA

Previous studies have shown that the interiors of proteins are densely packed, reaching packing fractions that are as large as those found for static packings of individual amino-acid-shaped particles. How can the interiors of proteins take on such high packing fractions given that amino acids are connected by peptide bonds and many amino acids are hydrophobic with attractive interactions? We investigate this question by comparing the structural and mechanical properties of collapsed attractive disk-shaped bead-spring polymers to those of three reference systems: static packings of repulsive disks, of attractive disks, and of repulsive disk-shaped bead-spring polymers. We show that the attractive systems quenched to temperatures below the glass transition T≪Tg and static packings of both repulsive disks and bead-spring polymers possess similar interior packing fractions. Previous studies have shown that static packings of repulsive disks are isostatic at jamming onset, i.e., the number of interparticle contacts Nc matches the number of degrees of freedom, which strongly influences their mechanical properties. We find that repulsive polymer packings are hypostatic at jamming onset (i.e., with fewer contacts than degrees of freedom) but are effectively isostatic when including stabilizing quartic modes, which give rise to quartic scaling of the potential energy with displacements along these modes. While attractive disk and polymer packings are often considered hyperstatic with excess contacts over the isostatic number, we identify a definition for interparticle contacts for which they can also be considered as effectively isostatic. As a result, we show that the mechanical properties (e.g., scaling of the potential energy with excess contact number and low-frequency contribution to the density of vibrational modes) of weakly attractive disk and polymer packings are similar to those of isostatic repulsive disk and polymer packings. Our results demonstrate that static

关键词： Jamming Polymer folding Protein folding Single polymer chains

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engineering dimensionality of collective dipole-dipole interactions using a nanophotonic environment

Engineering dimensionality of collective dipole-dipole inter...

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Conference on Lasers and Electro-Optics (CLEO)

作者： Ashwin K. Boddeti Yi Wang Xitlali Juarez Alexandra Boltasseva Hadiseh Alaeian Teri W. Odom Zubin Jacob Elmore Family School of Electrical and Computer Engineering and Birck Nanotechnology Center Purdue University West Lafayette Indiana USA Graduate Program in Applied Physics Northwestern University Evanston IL USA Department of Materials Science and Engineering Northwestern University Evanston Illinois USA Department of Chemistry and Department of Materials Science and Engineering Northwestern University Evanston Illinois USA

We experimentally demonstrate reduced dimensionality in a interacting ensemble of emitters. The well-known stretched exponential decay dynamics, I(t)/I 0 = exp(−γ D t)exp(−αt β ) with β = 0.5 in 3D geometries, is... 详细信息

ISBN: (纸本)9781957171258

关键词： Energy transfer Fluorescence Molecules Spontaneous emission Titanium dioxide

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