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SSRN 2023年

作者： Trzebiatowska, Patrycja Jutrzenka Maramorosz, Zofia Baluk, Mateusz A. Gazda, Maria Ecieza, Arantxa Zaleska-Medynska, Adriana Department of Environmental Technology Faculty of Chemistry University of Gdansk Gdańsk80-308 Poland Institute of Nanotechnology and Materials Engineering Faculty of Applied Physics and Mathematics Gdansk University of Technology Gabriela Narutowicza 11/12 Gdańsk80-233 Poland Group‘Materials+Technologies’ Department of Chemical and Environmental Engineering University of the Basque Country Plaza Europa Donostia-San Sebastián20018 Spain

chemical recycling of polycarbonate (PC) allows for obtaining valuable chemicals including monomers. However, it often needs the use of catalysts for mild reaction parameters and high conversion rates. In this work, we present the chemical recycling of PC using metal-organic frameworks (MOFs) as catalysts for a methanolysis reaction. The catalytic activity of various amine-containing MOFs, namely ZIF-8, MAF-6, and UiO-66-NH2, was explored due to their basic active sites, favourable for PC depolymerisation. Characterisation of MOFs included X-ray diffraction, infrared spectroscopy, scanning electron microscopy and isotherm Brunauer–Emmett–Teller analysis. We examined the impact of reaction parameters: temperature, catalyst content, and time, on PC recycling efficiency. Additionally, the post-synthetic modification (PSM) of MOF-5 was performed to determine its influence on catalytic activity. The methanolysis yielded two monomers: bisphenol A (BPA) and dimethyl carbonate (DMC). The conversion rate was calculated and also confirmed via nuclear magnetic resonance. The methanolysis of PC with MOF catalysts demonstrated enhanced conversion rates compared to the reaction without a catalyst, particularly with ZIF-8 and MAF-6 achieving nearly 100% PC conversion. The successful PSM of MOF-5 with ethylenediamine led to increased PC conversion. Also, the MOF-based catalysts were recovered and reused for up to three cycles. © 2023, The Authors. All rights reserved.

关键词： Scanning electron microscopy

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PPDONet: Deep Operator Networks for Fast Prediction of Steady-State Solutions in Disk-Planet Systems

arXiv

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arXiv 2023年

作者： Mao, Shunyuan Dong, Ruobing Lu, Lu Yi, Kwang Moo Wang, Sifan Perdikaris, Paris Department of Physics and Astronomy University of Victoria VictoriaBCV8P 5C2 Canada Department of Chemical and Biomolecular Engineering University of Pennsylvania PhiladelphiaPA19104 United States Department of Computer Science University of British Columbia VancouverBCV6T 1Z4 Canada Graduate Group in Applied Mathematics and Computational Science University of Pennsylvania PhiladelphiaPA19104 United States Department of Mechanical Engineering and Applied Mechanics University of Pennsylvania PhiladelphiaPA19104 United States

We develop a tool, which we name Protoplanetary Disk Operator Network (PPDONet), that can predict the solution of disk-planet interactions in protoplanetary disks in real-time. We base our tool on Deep Operator Networks (DeepONets), a class of neural networks capable of learning non-linear operators to represent deterministic and stochastic differential equations. With PPDONet we map three scalar parameters in a disk-planet system - the Shakura & Sunyaev viscosity α, the disk aspect ratio h0, and the planet-star mass ratio q - to steady-state solutions of the disk surface density, radial velocity, and azimuthal velocity. We demonstrate the accuracy of the PPDONet solutions using a comprehensive set of tests. Our tool is able to predict the outcome of disk-planet interaction for one system in less than a second on a laptop. A public implementation of PPDONet is available at https://***/smao-astro/PPDONet. Copyright © 2023, The Authors. All rights reserved.

关键词： Open source software

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Classic Fluorophores With a Horizontal Alignment for Enhancing Light Outcoupling Efficiency (≈30%) and External Quantum Efficiency (≈7%) of Near Ultraviolet (λmax < 400 nm) Organic Light-Emitting Diodes

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Advanced Optical Materials 2023年第8期11卷

作者： Lee, Jian Haur Huang, Jing-Xiang Chen, Chia-Hsun Lee, Yi-Ting Chan, Chin-Yiu Dzeng, Yi-Chung Tang, Po-Wen Chen, Chi Adachi, Chihaya Chiu, Tien-Lung Lee, Jiun-Haw Chen, Chin-Ti Sustainable Chemical Science and Technology Taiwan International Graduate Program and Institute of Chemistry Academia Sinica Taipei11529 Taiwan Department of Applied Chemistry National Yang Ming Chiao Tung University Hsinchu30010 Taiwan Department of Electrical Engineering Graduate Institute of Photonics and Optoelectronics National Taiwan University Taipei10617 Taiwan Kyushu University Fukuoka819-0395 Japan Research Center for Applied Sciences Academia Sinica Taipei11529 Taiwan Department of Electrical Engineering Yuan Ze University Taoyuan32003 Taiwan

Based on the classic 1,1′:4′,1″-terphenyl fluorophore, a novel near-ultraviolet (NUV) fluorescent BB4Ph (4,4″′-bis(2,3,4,5-tetraphenylphen-1-yl)(1,1′:4′,1″-terphenyl) is designed, synthesized, and characterized. BB4Ph exhibits a NUV fluorescence with a λmax of 373 and 380 nm in solution and as a thin film, respectively. The grazing incidence wide-angle X-ray scattering (GIWAXS) reveals BB4Ph having a high value of order parameter (SGIWAXS) of 0.59 for a molecular layer array normal to the substrate;the angle-dependent photoluminescence (ADPL) measurement shows Θ (horizontal–dipole ratios) as high as 95% with the neat film. The non-doped BB4Ph organic light-emitting diodes (OLEDs) show external quantum efficiency (EQE) up to 5.24% with 1931 Commission Internationale de l’ Eclairage coordinates (CIEx,y) of (0.16, 0.04), a NUV electroluminescence. With 4P-Cz (9,9′-(1,1′:4′,1″:4″,1′″-quaterphenyl-4,4′″-diyl)dicarbazole) as a dopant emitter, doped BB4Ph OLEDs show the highest EQE of 6.99% and a NUV 1931 CIEx,y (0.16, 0.04). The photoluminescence quantum yield is measured for the thin film of BB4Ph and 4P-Cz:BB4Ph as 68% and 96%, respectively. Hence, the low limits of light outcoupling efficiency (ηout) of the two individual OLEDs are estimated as 31% and 29%, respectively. © 2023 Wiley-VCH GmbH.

关键词： Thin films

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Using Diffusion Maps to Analyze Reaction Dynamics for a Hydrogen Combustion Benchmark Dataset

arXiv

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arXiv 2023年

作者： Ko, Taehee Heindel, Joseph Guan, Xingyi Head-Gordon, Teresa Williams-Young, David Yang, Chao Department of Mathematics Penn State University University ParkPA16802 United States Kenneth S. Pitzer Theory Center Department of Chemistry University of California BerkeleyCA94720 United States Departments of Bioengineering and Chemical and Biomolecular Engineering University of California BerkeleyCA94720 United States Applied Mathematics and Computational Research Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Chemical Sciences Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States

We use local diffusion maps to assess the quality of two types of collective variables (CVs) for a recently published hydrogen combustion benchmark dataset1 that contains ab initio molecular dynamics trajectories and normal modes along minimum energy paths. This approach was recently advocated in2 for assessing CVs and analyzing reactions modeled by classical molecular dynamics simulations. We report the effectiveness of this approach to molecular systems modeled by quantum ab initio molecular dynamics. In addition to assessing the quality of CVs, we also use global diffusion maps to perform committor analysis as proposed in.2 We show that the committor function obtained from the global diffusion map allows us to identify transition regions of interest in several hydrogen combustion reaction channels. Copyright © 2023, The Authors. All rights reserved.

关键词： Molecular dynamics

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Dynamics of a millimeter size drop exposed to MHz-frequency surface acoustic wave in the underlying solid substrate

arXiv

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arXiv 2023年

作者： Li, Y. Diez, J.A. D'Addesa, J. Manor, O. Cummings, L.J. Kondic, L. Department of Chemical Engineering Technion - Israel Institute of Technology Haifa32000 Israel Instituto de Física Arroyo Seco Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil7000 Argentina Department of Mathematical Sciences Center for Applied Mathematics and Statistics New Jersey Institute of Technology NewarkNJ07102 United States

We present an experimental, theoretical, and computational study of the spreading of a millimetric silicon oil drop under the excitation of a surface acoustic wave (SAW), traveling in the underlying solid substrate. Our fully time-dependent theoretical model is formulated within the long wave approach, and accounts carefully for the interaction between fluid dynamics and acoustic driving. While an approach similar to ours was used in previous works to analyze the dynamics of micron-scale films of oil and water under SAW excitation, the acoustic forcing was associated with boundary layer flow, i.e., Schlichting and Rayleigh streaming, and with acoustic radiation pressure. For the case considered here (millimetric thickness drops), the acoustic forcing is related to the Eckart streaming: the forcing mechanism is a result of variations in the Reynolds stress in the liquid, which is associated with variations in the intensity of ultrasonic wave leakage off the attenuating SAW under the drop. Schlichting and Rayleigh streaming contributions are usually negligible in this case. We find, in both experiments and simulations, that following an initial transient, where the oil drop deforms to accommodate the acoustic stress therein, the drop accelerates to reach translation at approximately constant speed for long times, while leaving a thin wetting layer behind. Our model suggests that the drop’s steady speed is due to the quasi-steady shape of the drop’s main body at long times, which is itself a consequence of the rate of SAW attenuation, which depends on the thickness of the liquid body above. The SAW attenuation is weak under air and the micron-thick liquid trail left behind the drop;it becomes significant once the SAW reaches the main body of the drop. Hence, the forcing on the drop is approximately the same, irrespective of its distance to the source of the SAW. The translating drop’s speed is found to be dependent on the drop size, as well as on the SAW intensity. The

关键词： Drops

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Spatiotemporal PET reconstruction with attenuation and motion correction

Spatiotemporal PET reconstruction with attenuation and motio...

引用

IEEE Symposium on Nuclear Science (NSS/MIC)

作者： E. Cece P. V.F.J. Meyrat O. Verdier E. Torino M. Colarieti-Tosti Division of Biomedical Imaging KTH Royal Institute of Technology Stockholm Sweden Department of Chemical Engineering Materials and Production University of Naples Federico II Naples Italy Department of Computing Mathematics and Physics HVL Western Norway University of Applied Sciences Bergen Norway Centro Interdipartimentale di Ricerca sui Biomateriali (CRIB) University of Naples Federico II Naples Italy

The diagnostic power of Positron Emission Tomography for early stage lung cancer is challenging since the lesion dimensions are comparable with the spatial resolution of modern clinical scanners and their contrast is decreased by respiratory motion. Moreover, strong artifacts in reconstructed images are introduced by attenuation, resulting in depression of activity in the middle of the image. In this paper we propose a modified version of Maximum Likelihood Activity and Attenuation (MLAA) algorithm, the Morphed-MLAA (M-MLAA), which, given gated data, jointly corrects for patient motion during the acquisition by composing the forward and backward operators with the registration fields between the different gates. The registration fields are evaluated with the deep-learning model Synthmorph. The main advantage of the proposed algorithm is that it makes use of the entire projection data set, thus improving the lesion signal-to-noise ratio, compared to the case in which images are reconstructed from a subset of the data. Our proposed algorithm has been tested on the XCAT phantom with some added lung lesions and shows improved performance for the detection and reconstruction of some of them; this improved performance is corroborated by the evaluation of two figures of merit (PSNR and RC). Our results show the potential of M-MLAA algorithm, but, at the same time, also that there is still space for improvements, since some lesions are better detected by the other more classical approaches, as MLAA single or total gates reconstructions.

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Red blood cell passage through deformable interendothelial slits in the spleen: Insights into splenic filtration and hemodynamics

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Computers in Biology and Medicine 2024年 182卷 109198-109198页

作者： Li, Guansheng Li, He Ndou, Papa Alioune Franco, Mélanie Li, Xuejin MacDonald, Ian Dao, Ming Buffet, Pierre A. Karniadakis, George Em Division of Applied Mathematics Brown University ProvidenceRI02906 United States School of Chemical Materials and Biomedical Engineering University of Georgia AthensGA30602 United States Université Paris Cité and Université des Antilles Inserm Biologie Intégrée du Globule Rouge Paris75015 France Laboratoire d'Excellence du Globule Rouge Paris75015 France Department of Engineering Mechanics and Center for X-Mechanics Zhejiang University Hangzhou Zhejiang310027 China Department of Medical Biophysics Schulich School of Medicine and Dentistry Western University LondonON Canada Department of Materials Science and Engineering Massachusetts Institute of Technology CambridgeMA02139 United States

The spleen constantly clears altered red blood cells (RBCs) from the circulation, tuning the balance between RBC formation (erythropoiesis) and removal. The retention and elimination of RBCs occur predominantly in the open circulation of the spleen, where RBCs must cross submicron-wide inter-endothelial slits (IES). Several experimental and computational studies have illustrated the role of IES in filtrating the biomechanically and morphologically altered RBCs based on a rigid wall assumption. However, these studies also reported that when the size of IES is close to the lower end of clinically observed sizes (less than 0.5 μm), an unphysiologically large pressure difference across the IES is required to drive the passage of normal RBCs, sparking debates on the feasibility of the rigid wall assumption. In this work, We propose two deformable IES models, namely the passive model and the active model, aiming to explore the impact of the deformability of IES on the filtration function of the spleen. In the passive model, we implement the worm-like string model to depict the IES's deformation as it interacts with blood plasma and allows RBC to traverse. In contrast, the active model involved regulating the IES deformation based on the local pressure surrounding the slit. To demonstrate the validity of the deformable model, we simulate the filtration of RBCs with varied size and stiffness by IES under three scenarios: (1) a single RBC traversing a single slit;(2) a suspension of RBCs traversing an array of slits, mimicking in vitro spleen-on-a-chip experiments;(3) RBC suspension passing through the 3D spleen filtration unit known as'the splenon’. Our simulation results of RBC passing through a single slit show that the deformable IES model offers more accurate predictions of the critical cell surface area to volume ratio that dictate the removal of aged RBCs from circulation compared to prior rigid-wall models. Our biophysical models of the spleen-on-a-chip indicate a hi

关键词： Hemodynamics

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A Spectral Analysis of the Nonlinear Schröedinger Equation in the Co-Exploding Frame

arXiv

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arXiv 2022年

作者： Jon Chapman, S. Kavousanakis, Mihalis E. Charalampidis, E.G. Kevrekidis, I.G. Kevrekidis, P.G. Mathematical Institute University of Oxford AWB ROQ Woodstock Road OxfordOX2 6GG United Kingdom School of Chemical Engineering National Technical University of Athens Athens15780 Greece Mathematics Department California Polytechnic State University San Luis ObispoCA93407-0403 United States Department of Chemical and Biomolecular Engineering Department of Applied Mathematics and Statistics Johns Hopkins University BaltimoreMD21218 United States Department of Mathematics and Statistics University of Massachusetts AmherstMA01003-4515 United States

The nonlinear Schrödinger model is a prototypical dispersive wave equation that features finite time blowup, either for supercritical exponents (for fixed dimension) or for supercritical dimensions (for fixed nonlinearity exponent). Upon identifying the self-similar solutions in the so-called "co-exploding frame", a dynamical systems analysis of their stability is natural, yet is complicated by the mixed Hamiltonian-dissipative character of the relevant frame. In the present work, we study the spectral picture of the relevant linearized problem. We examine the point spectrum of 3 eigenvalue pairs associated with translation, U(1) and conformal invariances, as well as the continuous spectrum. We find that two eigenvalues become positive, yet are attributed to symmetries and are thus not associated with instabilities. In addition to a vanishing eigenvalue, 3 more are found to be negative and real, while the continuous spectrum is nearly vertical and on the left-half (spectral) plane. Finally, the subtle effects of the boundaries are also assessed and their role in the observed weak eigenvalue oscillations is clarified. © 2022, CC0.

关键词： Eigenvalues and eigenfunctions

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Changes in fluoride removal ability of chicken bone char with changes in calcination time

International Journal of Ceramic Engineering and Science

引用

International Journal of Ceramic engineering and Science 2020年第2期2卷 83-91页

作者： Kikuchi, Masanori Arioka, Yuki Tafu, Masamoto Irie, Mitsuteru Bioceramics Group National Institute for Materials Science Tsukuba Japan Master's Program in Life Science Innovation University of Tsukuba Tsukuba Japan Department of Applied Chemistry and Chemical Engineering Toyama College National Institute of Technology Toyama Japan Faculty of Engineering University of Miyazaki Miyazaki Japan

Changes in fluoride removal ability of chicken bone char (CBC) were investigated by both remained amounts of carbon including organic substances and crystallite size of hydroxyapatite in the CBC. Carbon contents in CBC were controlled by heating time at 600°C. Although temperature for crystal-grain growth for HAp, 650°C, was higher than 600°C, crystallite size of HAp in CBC increased with heating time. Fluoride ion removal ability positively related to the amount of remaining carbon and negatively related to the square of crystallite size, as an index of surface area, of HAp. These results suggested that fluoride ion removal from water by CBC is not only by ion exchange and/or dissolution-precipitation process, but also by adsorption by carbon and/or temporal capture of fluoride ion by microstructure of carbonate in CBC before immobilize it in apatite structure. © 2019 The Authors. International Journal of Ceramic engineering & Science published by Wiley Periodicals, Inc. on behalf of American Ceramic Society.

关键词： Crystallite size

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Exploring Environmentally Friendly Corrosion Inhibitors: Insights from Natural and Biomass Residue-Derived Compounds

SSRN

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SSRN 2024年

作者： Othman, Norinsan Kamil Mohammed, Naba Jasim Yusop, Muhammed Rahimi Al-Gburi, Ahmed Jamal Abdullah Materials Science Program Department of Applied Physics Faculty of Science and Technology University Kebangsaan Malaysia Selangor Bangi43600 Malaysia Faculty of Science and Technology School of Chemical Sciences and Food Technology University Kepangsaan Malaysia Selangor Bangi43600 Malaysia Faculty of Electronics and Computer Engineering Universiti Teknikal Malaysia Melaka Hang Tuah Jaya Melaka Durian Tunggal76100 Malaysia

In this investigation, we explored the corrosive effects of date palm seed extracted from natural sources and biomass residues on mild steel in a solution of 0.5 M hydrochloric acid (HCl), employing a combination of experimental and theoretical approaches. Our objective was to scrutinize the interaction of the inhibitor with the metal surface, analyze experimental data, and elucidate how the structural characteristics of the inhibitors influence the corrosion process. The experimental results indicated that as the immersion time and temperature increased, the inhibitory effectiveness declined. Notably, the highest level of inhibition occurred when the concentration of date palm seed extract (DPSE) reached 1100 ppm, showcasing peak inhibitory effects of 95.8% and 97.8% through potentiodynamic polarization and electrochemical impedance spectroscopy techniques, respectively. Additionally, an analysis using X-ray diffraction (XRD) was conducted to scrutinize the chemical composition of the mild steel's surface. The adsorption data were evaluated using adsorption isotherms, revealing that DPSE adhered to the Langmuir adsorption isotherm on the mild steel surface. The Langmuir model exhibited the highest linear regression coefficient value and a slope close to unity. The Gibbs free energy () values suggested that the protection afforded by DPSE involved physical and spontaneous absorption. Examination of the results pertaining to the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) indicated that the carboxyl (COOH) group and the C=C bond were the principal regions exhibiting elevated electron acceptance activity. These components were found to be crucial in the adsorption process on the surface of iron (Fe). © 2024, The Authors. All rights reserved.

关键词： Electrochemical impedance spectroscopy

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