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Production and characterization of polymeric nanocomposite foams based on starch and cellulose nanofibers from oil palm mesocarp fiber

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Applied Nanoscience (Switzerland) 2025年第2期15卷 1-11页

作者： Souza, Mariana Costa Gonçalves, Ana Paula Bispo da Silva Oliveira, Emanoel Igor dos Santos, Juscivaldo Passos Lazzari, Lídia Kunz Zattera, Ademir José José, Nadia Mamede Chemical Engineering Graduate Program Polytechnic School Federal University of Bahia Bahia Salvador Brazil Department of Education Federal Institute of Education Science and Technology Feira de Santana Bahia Brazil Postgraduate Program in Process Engineering and Technologies University of Caxias Do Sul Rio Grande Do Sul Caxias Do Sul Brazil

The demand for sustainable and eco-friendly materials has promoted studies over the years to explore different polymeric materials that meet requirements such as biodegradability and sustainability. In this context, biopolymer materials based on cellulose nanoparticles and starch from different botanical sources have been investigated, aiming to achieve satisfactory performance. The present study aims to develop and characterize cassava starch foams based on density, scanning electron microscopy (SEM), and three-point flexure tests, and to evaluate the effect of cellulose nanofibers obtained from palm mesocarp fibers using the ultrafine friction grinding method after different processing times, characterized by X-ray diffractometry (XRD), microscopy, and chemical composition, as a reinforcing filler. The chemical composition and scanning electron microscopy revealed the effectiveness of the cellulose isolation process, with the analysis of the chemical composition revealing a cellulose content of 55.70% in the fibers after pulping and bleaching, in addition to changes in the visual characteristics of the material after the process aimed at isolating the cellulose. After grinding, XRD showed an increase in crystallinity (76.1% at the maximum grinding time), along with typical microscopy images of cellulose nanofibers. The analysis of the obtained nanocomposites provided insights into the role of these nanostructures in the thermo-expanded starch matrix, indicating that the nanofibers promoted changes such as an increase in mechanical properties and crystallinity, which contributed to improving overall mechanical performance. A 67.48% increase in flexural strength was achieved for the formulation with cellulose nanofibers that underwent 150 min of grinding, without causing major variations in density. © King Abdulaziz City for science and Technology 2025.

关键词： Starch

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Design and development of an integrated enset processing machine suitable for central highland farmers of west shewa zone Ethiopia

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Discover Agriculture 2025年第1期3卷 1-26页

作者： Jima, Beka Adugna Kolhe, Kishor Purushottam Jiru, Moera Gutu Agricultural Machinery Engineering Program Department of Mechanical Engineering School of Mechanical Chemical and Materials Engineering at Adama Science and Technology University Adama Ethiopia Department of Mechanical Engineering School of Mechanical Chemical and Materials Engineering at Adama Science and Technology University Adama Ethiopia

The development of Integrated Enset processing technology is significant for the easy availability of stable food in the current condition for fulfilling the pangs of hunger in Ethiopia, currently; individual manual technologies such as decortication, corm granting, bulla extraction, and fermenting techniques eventually contribute to utilizing food security such as Kocho, which is not affordable for the marginal farmers of Ethiopia. However, there is a lack of integrated compromise of the all-function process of corm granting, decortication, and pulverization in one machine wholesome of the product such as Kocho, and bulla within consuming time and labor. Therefore, it is decided to design and develop an integrated enset processing machine for central high land of Ethiopian farmers with high-quality production. The physical and mechanical properties of the enset is studied to get an efficient and robust design of the various components. The overall design and development of proposed machine components were carried out at Adama science and Technology University, Ethiopia by using ANSYS 2023 R1 software by considering the engineering economics and material specifications as per ASTM standards. The process parameters of the proposed machine are identified as feed rate, drum speed, concave to drum clearance, power requirement, etc. Also, the enset characteristics were considered as decorticating and granting, fiber cutting resistance, fiber length, dimension, shape, and weight. The overall developed enset integrated machine assembles are analyzed for granting and decorticating with drum clearance and bulla extraction throughput capacity, reliability, simplicity, safety, and overall cost. The machine's safety from a Design Perspective is checked and validated by a simulation study on the critical parts subjected to higher stresses. The cost of available individual decorticators, granting, pulverized, and bulla squeezer machines is costly to the farmer’s community. Theref

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Circularly polarized luminescence signals of photoresponsive liquid crystals and their applications

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Journal of Materials Chemistry C 2025年第19期13卷 9453-9464页

作者： Bao, Shengwen Li, Shan Tang, Ziran Wan, Yunhui Zhou, Guoquan Yang, Zehui Sun, Deli Ye, Danfeng Zhu, Liangliang School of Resources and Environmental Engineering Shanghai Polytechnic University No. 2360 Jinhai Road Shanghai201209 China College of Material Science and Chemical Engineering Ningbo University of Technology Ningbo315211 China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Fudan University Shanghai200438 China Zhe jiang Institute Tianjin University 201 Fenghua Road Ningbo315211 China

Photoresponsive liquid crystals have attracted much research attention due to their advantages of precision and non-contact regulation, among which the circularly polarized luminescence (CPL) properties have become a focal point in the field of liquid crystal research. Although photoluminescent crystals and CPL materials have been individually reviewed, there is a lack of a systematic review that comprehensively summarizes photoresponsive liquid crystal CPL and its mechanisms, influencing factors and applications. In order to study these molecules and their importance in scientific research in more depth, this paper reviews the research progress of photo responsive liquid crystal CPL, clarifies the interaction relationship between photo regulation and liquid crystal CPL, analyses the influence of doping ratios on their performance, and discusses advanced applications based on liquid crystal CPL. In addition, this paper highlights the importance of regulating the helical structure of liquid crystal systems by means of photos and the related mechanisms, and provides an outlook on the future development of this field. © 2025 The Royal Society of Chemistry.

关键词： Liquid crystals

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Enhancing compatibility and biodegradability of polylactic acid/biomass composites through torrefaction of forest residue

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Journal of Bioresources and Bioproducts 2025年第1期10卷 51-61页

作者： June-Ho Choi Myeong Rok Ahn Chae-Hwi Yoon Yeon-Su Lim Jong Ryeol Kim Hyolin Seong Chan-Duck Jung Sang-Mook You Jonghwa Kim Younghoon Kim Hyun Gil Cha Jae-Won Lee Hoyong Kim Center for Bio-based Chemistry Korea Research Institute of Chemical Technology(KRICT)Ulsan 44429South Korea Department of Wood Science and Engineering College of Agriculture and Life SciencesChonnam National UniversityGwangju 61186South Korea Interdisciplinary Program in IT-Bio Convergence System Chonnam National UniversityGwangju 61186South Korea

This study investigated the effects of torrefaction on forest residue(FR)and its subsequent ap-plication as a bulk-loading filler in polylactic acid(PLA)*** enhanced the chemical properties of FR,improving its compatibility with PLA,and the crystallinity increased from 24.9%to 42.5%.The process also improved the hydrophobicity of PLA/biomass composites,as demonstrated by the water contact angle of 76.1°,closely matching that of neat PLA(76.4°).With the introduction of 20%modified biomass properties after torrefaction treatment,the tensile strength of PLA/biomass composite increased from 58.7 to 62.3 ***,the addition of torrefied forest residue(TFR)accelerated biodegradation by increasing the onset of degrada-tion and inhibiting *** 90 d,the biodegradability of PLA/biomass composites reached 94.9%,which had a 6.9%increase compared to the neat PLA(88.8%).Overall,this study highlights the potential of torrefaction in enhancing both the physical properties and biodegrad-ability of PLA-based composites,contributing to a more sustainable approach to reducing plastic pollution.

关键词： Forest residue Torrefaction Bulk-loading filler Polylactic acid composite Hydrophobicity Tensile strength Biodegradability

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Zero Thermal Expansion Metamaterial Designs for Space Structures

Zero Thermal Expansion Metamaterial Designs for Space Struct...

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AIAA science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Lu, Wei-Chun Oudghiri-Idrissi, Othman Poli, Andrea Arruda, Ellen M. Tol, Serife Department of Mechanical Engineering University of Michigan 2350 Hayward St Ann ArborMI48109 United States Fariborz Maseeh Department of Civil Architectural and Environmental Engineering The University of Texas at Austin 301 E. Dean Keeton St AustinTX78712 United States Department of Mechanical Engineering Macromolecular Science and Engineering Program University of Michigan 2350 Hayward St Ann ArborMI48109 United States

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

The precision of space structures is sensitive to high-temperature variation during on-orbit operations. This work develops zero thermal expansion (ZTE) metamaterials that can be integrated into space structures to restrict large thermal deformation under precision requirements. The proposed bi-material ZTE metamaterial beams show extremely low coefficients of thermal expansion (CTE) for a wide temperature variation. Static and dynamic analyses are conducted on the designed metamaterials for performance evaluation. The proposed ZTE beam elements are integrated into a 48-meter rib of a space RF antenna to enhance its thermal precision over a wide temperature range. Further, experimental validation of the ZTE truss beam design is conducted in a thermal chamber to demonstrate its low thermal deformation compared to a reference aluminum truss beam. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Trusses

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The Influence of Silicon Dioxide as a Fuel Additive in a Diesel Engine Fuelled by Pure Palm Oil 4

The Influence of Silicon Dioxide as a Fuel Additive in a Die...

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4th International Symposium on Advances and Innovation in Mechanical engineering, ISAIME 2023

作者： Prahmana, Rico Aditia Darmanto, Prihadi Setyo Reksowardojo, Iman Kartolaksono Prakoso, Tirto Juangsa, Firman Bagja Doctoral Program of Mechanical Engineering Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung Bandung40132 Indonesia Program Study of Mechanical Engineering Faculty of Industrial Technology Institut Teknologi Sumatera South Lampung35365 Indonesia Thermal Science and Engineering Research Group Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung Bandung Indonesia Department of Chemical Engineering Faculty of Industrial Technology Institut Teknologi Bandung Bandung40132 Indonesia Program Study of Mechanical Engineering Faculty of Industrial Technology Universitas Pertamina Jakarta12220 Indonesia

In the last decade, the Indonesian government has implemented a program to use biodiesel as a substitute for fossil diesel to reduce dependence on fossil fuels. On the other hand, the development of biodiesel as an alternative fuel to replace fossil diesel has several challenges, one of which is the production of biodiesel, which is more complicated and requires a long process. However, the direct use of crude palm oil (CPO) in diesel engines is not recommended because it has many drawbacks. Research recently shows that fuel additives in diesel engines have promising prospects. Therefore, to solve the problem, this study used pure palm oil (PPaO) as the primary fuel, with the addition of silicon oxide (SiO2) as a fuel additive in diesel engines. The results showed that using SiO2 additive in PPaO can increase thermal efficiency by 18.8% at 60% load compared to diesel fuel (DF). Nevertheless, using this fuel increased specific fuel consumption (SFC) by 3.9% on average and increased the opacity by 153% compared to diesel fuel. These results indicate that SiO2 has the potential to be developed as an effective additive to PPaO fuel that can improve the efficiency and performance of diesel engines. © 2025 Institute of Physics Publishing. All rights reserved.

关键词： Biodiesel

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Advances in vat photopolymerization: early-career researchers shine light on a path forward

RSC Applied Polymers

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RSC Applied Polymers 2025年第3期3卷 574-591页

作者： Dhand, Abhishek P. Bean, Ren H. Chiaradia, Viviane Commisso, Alex J. Dranseike, Dalia Fowler, Hayden E. Fraser, Julia M. Howard, Holden Kaneko, Takashi Kim, Ji-Won Kronenfeld, Jason M. Mason, Keldy S. Pashley-Johnson, Fred Porcincula, Dominique H. Segal, Maddison I. Yu, Siwei Saccone, Max A. Department of Bioengineering University of Pennsylvania Philadelphia PA United States Sandia National Laboratories Albuquerque NM United States Department of Chemistry RCSI University of Medicine and Health Sciences Dublin Ireland Macromolecular Engineering Laboratory Department of Mechanical and Process Engineering ETH Zurich Zurich Switzerland Department of Chemistry University of Wisconsin-Madison Madison WI United States Materials Engineering Division Lawrence Livermore National Laboratory United States Department of Chemistry and Biochemistry University of California Santa Barbara CA United States Department of Chemical Engineering Kyungpook National University Daegu South Korea Department of Chemistry Stanford University Stanford CA United States Department of Chemistry The University of Texas at Austin Austin TX United States School of Chemistry and Physics Centre for Materials Science Queensland University of Technology (QUT) Brisbane QLD Australia Centre of Macromolecular Chemistry (CMaC) Department of Organic and Macromolecular Chemistry Faculty of Sciences Ghent University Ghent Belgium Thomas Lord Department of Mechanical Engineering & Material Science Duke University Durham NC United States Department of Chemistry University of Washington Seattle WA United States Department of Chemical Engineering Stanford University Stanford CA United States Paul M. Rady Department of Mechanical Engineering University of Colorado Boulder Boulder CO United States

Vat photopolymerization (VP) has emerged as a promising additive manufacturing technique to allow rapid light-based fabrication of 3D objects from a liquid resin. Research in the field of vat photopolymerization spans across multiple disciplines from engineering and materials science to applied chemistry and physics. This perspective brings together early-career researchers from various disciplines in academia and national laboratories around the world to summarize the most recent advancements with special emphasis on the research highlighted as part of the Gordon Research Conference (GRC) 2024 meeting on Additive Manufacturing of Soft Materials. We provide an outlook on next-generation polymer processing methods from synthesis of novel materials to multimodality manufacturing and performance engineering. Further, this article combines the ideas of many of these junior researchers to present a vision for the future of the field by highlighting the challenges and opportunities that lie ahead. © 2025 RSC.

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Combustion Profile of Bio-pellet Produced from Sawdust Using Wet Torrefaction Method with Various Concentrations of Acetic Acid 4

Combustion Profile of Bio-pellet Produced from Sawdust Using...

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4th International Symposium on Advances and Innovation in Mechanical engineering, ISAIME 2023

作者： Pertiwi, Indah Ayu Muhammad Abubakar Setiawan, Adi Iskandar, Rizky Magister Program in Renewable Energy Engineering Faculty of Engineering Universitas Malikusssaleh Jalan Batam Bukit Indah Lhokseumawe24352 Indonesia Chemical Engineering Department Faculty of Engineering Universitas Malikussaleh Kampus Bukit Indah Muara Satu Lhokseumawe24352 Indonesia Mechanical Engineering Vocational Education Study Program Faculty of Teaching and Educational Science Universitas Malikussaleh Cot Teungku Nie Reuleut Muara Batu Aceh Utara24355 Indonesia Mechanical Engineering Department Faculty of Engineering Universitas Malikusssaleh Jalan Batam Bukit Indah Lhokseumawe24352 Indonesia

Sawdust is one of the industrial wastes which naturally contains low energy density. An effective method is needed to utilize this biomass as a solid fuel product. This work aimed to investigate the physical and combustion properties of bio-pellets produced from sawdust under the wet torrefaction method. To prepare sawdust bio-pellet a number of steps were carried out including the wet torrefaction process, dough preparation, pelletizing, and drying. Wet torrefaction was performed by hydrothermally treating the sample in an autoclave at a temperature of 130°C and pressure of 2 atm (g) for 80 minutes. For the hydrothermal process, the used acetic acid solution was varied with variations of 1.3 M, 1.8 M, and 2.3 M. Properties of the product were analyzed under proximate and bomb calorimetry analyses. To evaluate the combustion properties a purposely built test apparatus was developed equipped with a data logger system. Based on the results it can be observed that increases in torrefaction temperature and acetic acid concentration resulted in an increase in the calorific value as well as decreases in the ash content. The highest calorific value was 4745 kcal/kg obtained from sawdust torrefied in acetic acid with a concentration of 2.3 M at a temperature of 130?. This sample also exhibits the lowest ash content which is only 1.97%. The combustion test disclosed a maximum combustion temperature of 589? with a burning rate of 0.711 g/min. Overall, the wet torrefaction applied in this investigation was beneficially enhanced the properties of bio-pellet products. © 2025 Institute of Physics Publishing. All rights reserved.

关键词： Sawdust

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Fluorescent Sodium Alginate Hydrogel-Carbon Dots Sensor for Detecting Perfluorooctanoic Acid in Potable Water

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Analytical Chemistry 2025年第18期97卷 10075-10084页

作者： Mohammadi, Somayeh Sandoval-Pauker, Christian Dorado, Zayra N. Senftle, Thomas P. Pankow, Robert Sharifan, Hamidreza Department of Chemistry and Biochemistry University of Texas at El Paso El PasoTX79968 United States Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Metallurgical & Materials Engineering The University of Texas at El Paso 500 West University Avenue El PasoTX79902 United States Department of Chemical and Biomolecular Engineering Rice University HoustonTX77005 United States Environmental Science and Engineering Program University of Texas at El Paso El PasoTX79968 United States

Per- and polyfluoroalkyl substances (PFASs), especially perfluorooctanoic acid (PFOA), are emerging environmental and health concerns due to their persistence, resistance to degradation, and bioaccumulation. In this study, we developed a sensitive and selective detection platform based on a sodium alginate (SA) hydrogel modified with nitrogen and fluorinated carbon dots (N,F-CDs) to enhance the detection of PFOA in natural and engineered water systems. The SA hydrogel-N,F-CD composite exhibited strong fluorescence at 480 nm after optimization, achieving a detection limit as low as 0.001 ppt. The sensor was characterized by using Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FT-IR), Powder X-ray Diffraction (PXRD), X-ray Photoelectron Spectroscopy (XPS), and zeta potential spectroscopy, revealing its structural integrity, functional groups, and the surface charge of the SA hydrogel-N,F-CDs network. Sensitivity assessments demonstrated a linear fluorescence response to PFOA concentrations ranging from 1 to 66 ppq. Selectivity tests confirmed the sensor’s ability to distinguish PFOA from other perfluorinated compounds, with minimal interference from other substances. The practical applicability of the sensor was validated using spiked recovery experiments with tap water samples from various locations, achieving recovery rates between 94% and 106.6%. This sensor offers a reliable, efficient, and highly sensitive platform for the detection of PFAS, demonstrating its potential for real-world PFAS-monitoring applications. © 2025 American chemical Society.

关键词： Fourier transform infrared spectroscopy

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Deciphering Self-Assembly Mechanisms of IRMOF-n-Inspired Three-Dimensional Cubic-Symmetry Nanoporous Crystals from Multiscale Simulations

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Chemistry of Materials 2025年第10期37卷 3799-3812页

作者： Ardila, Katherine Liu, Tsung-Wei Gómez-Gualdrón, Diego A. Pak, Alexander J. Department of Chemical and Biological Engineering Colorado School of Mines 1601 Illinois Street Golden 80401 CO United States Materials Science Program Colorado School of Mines 1601 Illinois Street Golden 80401 CO United States Quantitative Biosciences and Engineering Program Colorado School of Mines 1601 Illinois Street Golden 80401 CO United States

The formation mechanisms of metal−organic frameworks (MOFs) are not fully understood. Therefore, experimental realization of potential “breakthrough” MOFs is hindered by uncertainty in the synthesis conditions that would allow the constituent nodes and linkers to self-assemble into the targeted MOF structure. Here, a multiscale endeavor using density functional theory (DFT) calculations, followed by metadynamics with DFT-informed classical atomistic potentials, followed by standard molecular dynamics (MD) and Hamiltonian replica exchange (HREX) simulations with a metadynamics-informed, coarse-grained (CG) model, was used to study the self-assembly mechanism of cubic-symmetry porous crystals inspired by the IRMOF-n family of MOFs. Mechanistic differences were examined for different values of node-linker coordination strength─understood as the free energy penalty for breaking a coordination bond in a solvated environment. Our integrated analyses of HREX-derived free energy surfaces and standard MD trajectories indicate that at coordination strengths typical of the IRMOF-n family in dimethylformamide (DMF) (i.e., 52 kJ/mol), disassembled nodes and linkers are favored to overcome a small 1.3 kJ/mol free energy barrier to first form solid amorphous clusters, which then overcome a series of barriers (the largest of which is 3.7 kJ/mol) to heal and form ordered, more stable, cubic-symmetry crystals. This healing seems to occur through the splintering/reattaching of small clusters from/to large clusters. Our analyses also suggest that if coordination strength is moderately weakened (e.g., to 40 kJ/mol), crystals form without the preliminary formation of amorphous clusters. However, further coordination strength weakening (e.g., to 36 kJ/mol) makes the formation of sizable crystals unfavorable thermodynamically. On the other hand, strengthening the coordination would increase the free energy barrier to heal the amorphous clusters into crystals. Accordingly, if coordination b

关键词： Hamiltonians

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