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Thermal Degradation and Kinetic Study of Cassava Rhizome for Torrefaction Application

IOP Conference Series: Earth and Environmental science 2019年第1期401卷

作者： P Sirinwaranon D Atong V Sricharoenchaikul Interdisciplinary Program in Environmental Science Graduated School Chulalongkorn University Bangkok 10330 Thailand National Metal and Materials Technology Center (MTEC) National Science and Technology Development Agency (NSTDA) Thailand Science Park Pathum Thani 12120 Thailand Faculty of Engineering Department of Environmental Engineering Chulalongkorn University Bangkok 10330 Thailand

Thermal decomposition kinetics of cassava rhizome (CR) is an important key in the torrefaction process. Kinetic analysis of the cassava rhizome torrefaction was investigated using a thermogravimetric analyser in which CR weight loss is measured under nitrogen atmosphere from ambient temperature to 973K at 5, 10, 20, and 30 Kmin−1. Two model-free iso-conversional methods, Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) have been used to determine activation energies as a function of the extent of degradation. In this work, the CR particles were separated into 3 study groups, 0.125-0.425 mm, 0.425-0.850, and 0.850-2 mm. The average activation energies calculated by using the methods are relatively similar for all three-particle size samples. The average activation energy values calculated by FWO method were 170.509, 172.593, and 130.149 kJmol−1, respectively. These data were comparable to KAS method in which the average activation energy numbers were 170.647, 177.276, and 128.620 kJmol−1. Both methods indicated that the activation energy was relatively constant until the conversion of 0.5. The pre-exponential factor values from FWO and KAS ranged 4.87E+17 s−1 and 7.28E+14 s−1, respectively. The experimental results show that kinetic parameters from both methods are suitable and effective to help describe the thermal degradation of the cassava rhizome.

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Band gap and band alignment prediction of nitride based semiconductors using machine learning

arXiv

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arXiv 2018年

作者： Huang, Yang Yu, Changyou Chen, Weiguang Liu, Yuhuai Li, Chong Niu, Chunyao Wang, Fei Jia, Yu International Laboratory for Quantum Functional Materials of Henan School of Physics and Engineering Zhengzhou University Zhengzhou450001 China Materials Science and Engineering Program University of California San Diego La JollaCA92093 United States National Center for International Joint Research of Electronic Materials and Systems School of Information Engineering Zhengzhou University Zhengzhou450001 China Quantum Materials Research Center College of Physics and Electronic Engineering Zhengzhou Normal University Zhengzhou450044 China Institute of Materials and Systems for Sustainability Nagoya University Nagoya464-8603 Japan Key Laboratory for Special Functional Material of Ministry of Education School of Materials Science Henan University Kaifeng475004 China

Nitride has been drawing much attention due to its wide range of applications in optoelectronics and remains plenty of room for materials design and discovery. Here, a large set of nitrides have been designed, with their band gap and alignment being studied by first-principles calculations combined with machine learning. Band gap and band offset against wurtzite GaN accurately calculated by the combination of screened hybrid functional of HSE and DFT-PBE were used to train and test machine learning models. After comparison among different techniques of machine learning, when elemental properties are taken as features, support vector regression (SVR) with radial kernel performs best for predicting both band gap and band offset with prediction root mean square error (RMSE) of 0.298 eV and 0.183 eV, respectively. The former is within HSE calculation uncertainty and the latter is small enough to provide reliable predictions. Additionally, when band gap calculated by DFT-PBE was added into the feature space, band gap prediction RMSE decreases to 0.099 eV. Through a feature engineering algorithm, elemental feature space based band gap prediction RMSE further drops by around 0.005 eV and the relative importance of elemental properties for band gap prediction was revealed. Finally, band gap and band offset of all designed nitrides were predicted and two trends were noticed that as the number of cation types increases, band gap tends to narrow down while band offset tends to go up. The predicted results will be a useful guidance for precise investigation on nitride engineering. Copyright © 2018, The Authors. All rights reserved.

关键词： Energy gap

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Enhancing the yield and quality of Kemiri Sunan crude oil by preliminary extraction of feedstock

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Journal of Physics: Conference Series 2019年第1期1295卷

作者： S Supriyadi P Purwanto P H Hermawan Doctoral Program of Environmental Science School of Postgraduate Studies Diponegoro University Semarang- Indonesia Department of Mechanical Engineering Universitas PGRI Semarang Semarang- Indonesia Department of Chemical Engineering Faculty of Engineering Diponegoro University Semarang Indonesia Department of Electrical Engineering Faculty of Engineering Diponegoro University Semarang – Indonesia

Biodiesel is an alternative fuel produced by chemical reaction between vegetable oil or animal fat with alcohol and catalyst. The preliminary treatment in extraction of biodiesel feedstock is an important process to obtain maximum yield of crude oil. This study aims to find optimal preliminary treatment on extraction of Kemiri Sunan seed in order to produce crude oil with maximum yield and quality. The research investigated the effects of screw press machine rotation and duration of steaming process. Three levels of duration of steaming used were 30, 60 and 90 minutes. Observations of crude oil yield, moisture content, free fatty acid content, kinematic viscosity, density and color were done. The result suggested that the rotation of screw press machine affected the crude oil yield. The duration of steaming process affected the oil yield, free fatty acid content, kinematic viscosity, density and color. The best oil yield result of 70.3% was obtained from the combination of heating duration of 60' and screw rotation of 25 RPM.

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Atomic-scale mechanism of internal structural relaxation screening at polar interfaces

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Physical Review B 2018年第18期97卷 180103(R)-180103(R)页

作者： Mingqiang Li Xiaoxing Cheng Ning Li Heng-Jui Liu Yen-Lin Huang Kaihui Liu Ying-Hao Chu Dapeng Yu Long-Qing Chen Yuichi Ikuhara Peng Gao Electron Microscopy Laboratory and International Center for Quantum Materials School of Physics Peking University Beijing 100871 China Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China Department of Materials Science and Engineering The Pennsylvania State University University Park Pennsylvania 16802 USA Department of Materials Science and Engineering National Chung Hsing University Taichung 40227 Taiwan Republic of China Department of Materials Science and Engineering National Chiao Tung University Hsinchu 30010 Taiwan Republic of China Collaborative Innovation Centre of Quantum Matter Beijing 100871 China State Key Laboratory for Mesoscopic Physics School of Physics Peking University Beijing 100871 China Institute of Physics Academia Sinica Taipei 11529 Taiwan Republic of China Department of Physics South University of Science and Technology of China Shenzhen 518055 China Institute of Engineering Innovation The University of Tokyo Tokyo 113-8656 Japan Nanostructures Research Laboratory Japan Fine Ceramic Centre Nagoya 456-8587 Japan

The effective screening of the polarization bound charge is a prerequisite to stabilize the ferroelectricity in ferroelectric thin films. Here, by combining annular bright field imaging and electron energy-loss spectroscopy (EELS) in an aberration-corrected scanning transmission electron microscope with phase-field simulations, we investigate the screening mechanism by quantitatively measuring the structural relaxation at Pb(Zr0.2Ti0.8)O3/SrTiO3 interfaces. We find that the thickness of the interfacial layer is ∼3.5 unit cells (∼1.4 nm) in a domain with upward polarization and ∼5.5 unit cells (∼2.2 nm) in a domain with downward polarization. Phase-field simulations, an EELS analysis, and a lattice parameter analysis verify the existence of interfacial oxygen vacancies accounting for the narrower interfacial layer in the domain with upward polarization. Our study indicates the internal structural relaxation at the interface is the dominant mechanism for the polarization charge screening for ferroelectric films grown on insulating substrates and has implications for our understanding of domain switching in ferroelectric devices.

关键词： Ferroelectricity Surface & interfacial phenomena Thin films Electron energy loss spectroscopy Transmission electron microscopy

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Effects of carbon fiber on mechanical and electrical properties of fly ash geopolymer composite

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materials Today: Proceedings 2018年第6期5卷 14017-14025页

作者： Panjasil Payakaniti Supree Pinitsoonthorn Prasit Thongbai Vittaya Amornkitbamrung Prinya Chindaprasirt Materials Science and Nanotechnology Program Department of Physics Faculty of Science Khon Kaen University Khon Kaen 40002 Thailand Integrated Nanotechnology Research Center Department of Physics Faculty of Science Khon Kaen University Khon Kaen 40002 Thailand Nanotec-KKU Center of Excellence on Advanced Nanomaterials for Energy Production and Storage Khon Kaen University Khon Kaen 40002 Thailand Sustainable Infrastructure Research and Development Center Department of Civil Engineering Faculty of Engineering Khon Kaen University Khon Kaen 40002 Thailand

High calcium fly ash geopolymer composite was prepared by incorporating short carbon fiber in the geopolymer matrix. The carbon fiber (CF) content was varied from 0 to 1%, the liquid to ash ratio was controlled at 0.5. The workability, mechanical and electrical properties of the geopolymer composites were examined. The result showed that the incorporation of 0.5%CF and above resulted in the ductile failure of specimen. The increasing CF content also resulted in decreasing workability and mechanical strength. The electrical resistivity was also reduced and was more stable to the curing age and temperature. The cyclic voltammetry (CV) curve of 60°C curing provided less peaks than that of 25°C.

关键词： Geopolymer Alkaline activated binder Mechanical Properties Electrical properties

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Potassium Metal Batteries: Stable Potassium Metal Anodes with an All‐Aluminum Current Collector through Improved Electrolyte Wetting (Adv. Mater. 49/2020)

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Advanced materials 2020年第49期32卷 2070365-2070365页

作者： Pengcheng Liu Yixian Wang Hongchang Hao Swastik Basu Xuyong Feng Yixin Xu Jorge Anibal Boscoboinik Jagjit Nanda John Watt David Mitlin Materials Science and Engineering Program & Texas Materials Institute (TMI) The University of Texas at Austin Austin TX 78712‐1591 USA Center for Functional Nanomaterials Brookhaven National Laboratory Upton NY 11973 USA Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37830 USA Center for Integrated Nanotechnologies Los Alamos National Laboratory Los Alamos NM 87545 USA

An explorer is kayaking in uncharted territory, representing the exciting scientific pursuit of emerging metal batteries (MBs). Water is flowing smoothly over the jagged rocks, representing dendrite‐free metal anodes as well as enhanced electrolyte wetting, both due to geometrical roughness. The electric eels underneath represent potassium‐based energy storage, as they utilize potassium and sodium ions for electricity. In article number 2002908, Pengcheng Liu, David Mitlin, and co‐workers present a route via improved electrolyte wetting toward stable potassium metal batteries with an all‐aluminum current collector.

关键词： lithium metal batteries lithium–sulfur batteries potassium‐ion batteries potassium–sulfur batteries sodium metal batteries

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A mixed convection heat transfer benchmark test case: The prismatic-core advanced high temperature reactor 17

A mixed convection heat transfer benchmark test case: The pr...

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17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, NURETH 2017

作者： Alameri, Saeed A. Addad, Yacine King, Jeffrey C. Department of Nuclear Engineering Khalifa University of Science and Technolog P.O. Box 127788 Abu Dhabi United Arab Emirates Nuclear Science and Engineering Program Department of Metallurgical and Materials Engineering Colorado School of Mines 1500 Illinois Street GoldenCO80401 United States

A thermal-hydraulic sub-channel calculation for a Prismatic-core Advanced High Temperature Reactor (PAHTR) design is investigated. In particular, the investigation focuses on the Star-CCM+’s global discretization error order, with this finite volume code, for forced and mixed convection heat transfer cases pertinent to the nuclear industry. To achieve this, the commercial code Star-CCM+ is used to study the flow and thermal hydraulic conditions of a single coolant channel. First the CFD model for a single channel of the PAHTR is benchmarked and validated against existing correlations for developing forced convection flow. This comparison has allowed a Verification and Validation (V&V) of the commercial code Star-CCM+. The obtained results with the reactor’s operating heat flux values reveal that the flow within the PAHTR core remains in the developing mixed convection regime. Nusselt number and friction coefficient profiles along the pipe’s streamwise direction are directly affected by the heat flux magnitude and distribution. In fact, existing correlations either;do not take buoyancy effects in account or are not within the flow conditions range, hence, the CFD predictions are used to produce more suitable correlations taking in account this mixed convection regime. As for the commercial code used, the global numerical error of the Star-CCM+ CFD code is, as expected, approaching the 2nd order. © 2016 Association for Computing Machinery Inc. All Rights Reserved.

关键词： Hydraulics

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Suppressing decoherence in quantum plasmonic systems by spectral hole burning effect

arXiv

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arXiv 2020年

作者： You, Jia-Bin Xiong, Xiao Bai, Ping Zhou, Zhang-Kai Yang, Wan-Li Png, Ching Eng Kwek, Leong Chuan Wu, Lin 1 Fusionopolis Way #16-16 Connexis 138632 Singapore State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Yat-sen University Guangzhou510275 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan430071 China Centre for Quantum Technologies National University of Singapore 3 Science Drive 2 117543 Singapore MajuLab CNRS-UNS-NUS-NTU International Joint Research Unit UMI 3654 Singapore National Institute of Education and Institute of Advanced Studies Nanyang Technological University 1 Nanyang Walk 637616 Singapore School of Electrical and Electronic Engineering Block S2.1 50 Nanyang Avenue 639798 Singapore

Quantum plasmonic systems suffer from significant decoherence due to the intrinsically large dissipative and radiative dampings. Based on our quantum simulations via a quantum tensor network algorithm, we numerically demonstrate the mitigation of this restrictive drawback by hybridizing a plasmonic nanocavity with an emitter ensemble with inhomogeneously-broadened transition frequencies. By burning two narrow spectral holes in the spectral density of the emitter ensemble, the coherent time of Rabi oscillation for the hybrid system is increased tenfold. With the suppressed decoherence, we move one step further in bringing plasmonic systems into practical quantum applications. Copyright © 2020, The Authors. All rights reserved.

关键词： Quantum theory

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Photoemission spectroscopic evidence for the dirac nodal line in monoclinic semimetal SrAs3

arXiv

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arXiv 2019年

作者： Song, Y.K. Wang, G.W. Li, S.C. Liu, W.L. Lu, X.L. Liu, Z.T. Li, Z.J. Wen, J.S. Yin, Z.P. Liu, Z.H. Shen, D.W. State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai200050 China School of Physical Science and Technology ShanghaiTech University Shanghai200031 China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing100049 China Department of Physics Center for Advanced Quantum Studies Beijing Normal University Beijing100875 China National Laboratory of Solid State Microstructures Department of Physics Nanjing University Nanjing210093 China University of Chinese Academy of Sciences Beijing100049 China Shanghai200050 China Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing210093 China

Topological nodal-line semimetals with exotic quantum properties are characterized by symmetry-protected line-contact bulk band crossings in the momentum space. However, in most of identified topological nodalline compounds, these topological non-trivial nodal lines are enclosed by complicated topological trivial states at the Fermi energy (EF), which would perplex their identification and hinder further applications. Utilizing angle-resolved photoemission spectroscopy and first-principles calculations, we provide compelling evidence for the existence of Dirac nodal-line fermions in the monoclinic semimetal SrAs3, which are close to EFand away from distraction of complex trivial Fermi surfaces or surface states. Our calculation indicates that two bands with opposite parity are inverted around Y near EF, which results in the single nodal loop at the G-YS plane with a negligible spin-orbit coupling effect. We track these band crossings and then unambiguously identify the complete nodal loop quantitatively, which provides a critical experimental support to the prediction of nodal-line fermions in the CaP3family of materials. Hosting simple topological non-trivial bulk electronic states around EFand no interfering with surface states on the natural cleavage plane, SrAs3is expected to be a potential platform for topological quantum state investigation and applications. Copyright © 2019, The Authors. All rights reserved.

关键词： Surface states

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The PLATO mission

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Experimental Astronomy 2025年第3期59卷 1-111页

作者： Rauer, Heike Aerts, Conny Cabrera, Juan Deleuil, Magali Erikson, Anders Gizon, Laurent Goupil, Mariejo Heras, Ana Walloschek, Thomas Lorenzo-Alvarez, Jose Marliani, Filippo Martin-Garcia, César Mas-Hesse, J. Miguel O’Rourke, Laurence Osborn, Hugh Pagano, Isabella Piotto, Giampaolo Pollacco, Don Ragazzoni, Roberto Ramsay, Gavin Udry, Stéphane Appourchaux, Thierry Benz, Willy Brandeker, Alexis Güdel, Manuel Janot-Pacheco, Eduardo Kabath, Petr Kjeldsen, Hans Min, Michiel Santos, Nuno Smith, Alexis Suarez, Juan-Carlos Werner, Stephanie C. Aboudan, Alessio Abreu, Manuel Acuña, Lorena Adams, Moritz Adibekyan, Vardan Affer, Laura Agneray, François Agnor, Craig Aguirre Børsen-Koch, Victor Ahmed, Saad Aigrain, Suzanne Al-Bahlawan, Ashraf Alcacera Gil, Ma de los Angeles Alei, Eleonora Alencar, Silvia Alexander, Richard Alfonso-Garzón, Julia Alibert, Yann Allende Prieto, Carlos Almeida, Leonardo Alonso Sobrino, Roi Altavilla, Giuseppe Althaus, Christian Alvarez Trujillo, Luis Alonso Amarsi, Anish Ammler-von Eiff, Matthias Amôres, Eduardo Andrade, Laerte Antoniadis-Karnavas, Alexandros António, Carlos Aparicio del Moral, Beatriz Appolloni, Matteo Arena, Claudio Armstrong, David Aroca Aliaga, Jose Asplund, Martin Audenaert, Jeroen Auricchio, Natalia Avelino, Pedro Baeke, Ann Baillié, Kevin Balado, Ana Ballber Balagueró, Pau Balestra, Andrea Ball, Warrick Ballans, Herve Ballot, Jerome Barban, Caroline Barbary, Gaële Barbieri, Mauro Barceló Forteza, Sebastià Barker, Adrian Barklem, Paul Barnes, Sydney Barrado Navascues, David Barragan, Oscar Baruteau, Clément Basu, Sarbani Baudin, Frederic Baumeister, Philipp Bayliss, Daniel Bazot, Michael Beck, Paul G. Belkacem, Kevin Bellinger, Earl Benatti, Serena Benomar, Othman Bérard, Diane Bergemann, Maria Bergomi, Maria Bernardo, Pierre Biazzo, Katia Bignamini, Andrea Bigot, Lionel Billot, Nicolas Binet, Martin Biondi, David Biondi, Federico Birch, Aaron C. Bitsch, Bertram Bluhm Ceballos, Paz Victoria Bódi, Attila Bognár, Zsófia Boisse, Isabelle Bolmont, Emeline Bonanno, Alfio Bonavita, Institut für Planetenforschung Deutsches Zentrum für Luft- und Raumfahrt DLR Rutherfordstrasse 2 Berlin 12489 Germany Fachbereich Geowissenschaften Institut für Geologische Freie Universität Berlin Malteserstr. 74-100 Berlin 12249 Germany Institute of Astronomy KU Leuven Leuven Belgium CNRS CNES LAM Aix Marseille University Marseille France Max Planck Institute for Solar System Research Göttingen Germany LESIA Paris Observatory PSL University Sorbonne University Paris Cité University CNRS Meudon France ESTEC European Space Agency Noordwijk Netherlands ESAC European Space Agency Madrid Spain Centro de Astrobiología CSIC-INTA Campus ESAC Madrid Spain Center for Space and Habitability University of Bern Bern Switzerland INAF - Osservatorio Astrofisico di Catania Catania Italy Department of Physics and Astronomy University of Padua Padua Italy Department of Physics University of Warwick Coventry United Kingdom Astronomical Observatory of Padova INAF - Italian National Institute for Astrophysics Padua Italy Armagh Observatory and Planetarium College Hill Armagh United Kingdom Geneve Observatory University of Geneve Geneve Switzerland IAS University of Paris-Saclay Orsay France AlbaNove University Centre Stockholm University Stockholm Sweden Department of Astrophysics University of Vienna Vienna Austria Department of Astronomy University of Sao Paulo Sao Paulo Brazil Astronomical Institute of the Czech Academy of Sciences Ondřejov Czech Republic Department of Physics and Astronomy Aarhus University Aarhus Denmark Institute for Space Research SRON Leiden Netherlands Instituto de Astrofísica e Ciências do Espaço CAUP Universidade do Porto Porto Portugal Departamento de Física e Astronomia Faculdade da Ci ncias Universidade do Porto Porto Portugal Mullard Space Science Laboratory University College London Holmbury Saint Mary United Kingdom Dept. Theoretical Physics and the Cosmos University of Granada Granada Spain Centre for Plan

PLATO (PLAnetary Transits and Oscillations of stars) is ESA’s M3 mission designed to detect and characterise extrasolar planets and perform asteroseismic monitoring of a large number of stars. PLATO will detect small planets (down to <2REarth) around bright stars (<11 mag), including terrestrial planets in the habitable zone of solar-like stars. With the complement of radial velocity observations from the ground, planets will be characterised for their radius, mass, and age with high accuracy (5%, 10%, 10% for an Earth-Sun combination respectively). PLATO will provide us with a large-scale catalogue of well-characterised small planets up to intermediate orbital periods, relevant for a meaningful comparison to planet formation theories and to better understand planet evolution. It will make possible comparative exoplanetology to place our Solar System planets in a broader context. In parallel, PLATO will study (host) stars using asteroseismology, allowing us to determine the stellar properties with high accuracy, substantially enhancing our knowledge of stellar structure and evolution. The payload instrument consists of 26 cameras with 12cm aperture each. For at least four years, the mission will perform high-precision photometric measurements. Here we review the science objectives, present PLATO‘s target samples and fields, provide an overview of expected core science performance as well as a description of the instrument and the mission profile towards the end of the serial production of the flight cameras. PLATO is scheduled for a launch date end 2026. This overview therefore provides a summary of the mission to the community in preparation of the upcoming operational phases. © The Author(s) 2025.

关键词： Asteroseismology Exoplanets PLATO mission

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