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Strengthening Cu-S Bond Via Rational Design of Tricopper Complex with Superior Π-Acidity for Enhanced Adsorption Desulfurization Selectivity

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SSRN

SSRN 2023年

作者： Feng, Xiaoquan Qu, Lulu Zhang, Yatao Hou, Hongwei Ng, Seik Weng Yang, Guang National Supercomputing Center in Zhengzhou Zhengzhou University Henan Zhengzhou450001 China Green Catalysis Center College of Chemistry Zhengzhou University Henan Zhengzhou450001 China School of Chemical Engineering Zhengzhou University Zhengzhou450001 China Faculty of Applied Sciences UCSI University Kuala Lumpur Cheras Malaysia

Adsorptive desulfurization (ADS) is a promising technique with low energy-consumption process for producing ultra-low sulfur fuels, however, it usually suffers from the low adsorptive selectivity in the presence of organic competitors. Herein, we report a "molecule-based" adsorbent tricopper complex (Cu3pz3) with superior π-acidity for enhancement of adsorption desulfurization selectivity by strengthening Cu-S bond. As expected, the triangular copper(I) complex as adsorbent in low-concentration sulfurous fuel (100 mg S/L) with stubborn competitor (toluene) can achieve a high selectivity, e.g., the S-content (as DBT) can be reduced to ~ 9 mg S/L in the toluene-iso-octane model oil (v:v = 15:85) corresponding to an adsorbent dose of 3.65 g/L, which is much better than the adsorption performance exhibited by the structurally similar– Ag3pz3 in our previous report and other typical porous materials adsorbent. Furthermore, the adsorption mechanism has been investigated at a molecular level, including the identification and structure determination of the adsorption products, theoretical calculation and analysis, which unveils a correlation between the ADS selectivity and the strength of Cu-S bonding. This work provides a new conceptual approach of using zero-dimensional tricopper complex with superior π-acidity as adsorbent for enhancement of adsorption desulfurization selectivity, which can accomplish adsorption desulfurization, also indicating molecular design strategies for further improvement of ADS selectivity. © 2023, The Authors. All rights reserved.

关键词： Adsorption

Lattice distortion tuning resistivity invar effect in high entropy alloys

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arXiv 2025年

作者： Chen, Hao Xu, Yuanji Liu, Lihua Chen, Yue Wróbel, Jan Cong, Daoyong Tian, Fuyang Wang, Yang Institute for Applied Physics University of Science and Technology Beijing Beijing100083 China Department of Mechanical Engineering The University of HongKong Pokfulam Road Hong Kong Faculty of Materials Science and Engineering Warsaw University of Technology Woloska 141 Warsaw02-507 Poland State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing China Department of Mechanical Engineering The University of HongKong Pokfulam999077 Hong Kong Pittsburgh Supercomputing Center Carnegie Mellon University PittsburghPA15213 United States

Materials with an ultra-low temperature coefficient of resistivity are desired for the temperature and flow sensors in high-precision electronic measuring systems. In this work, the Kubo-Greenwood formula, implemented in ab initio molecular dynamics simulations, is employed to predict the finite-temperature resistivity of multi-component alloys with severe lattice distortion. We observe a tiny change in resistivity over a wide temperature range in high-entropy alloys. The electronic resistivity invar effect in B2 Ni25Co25(HfTiZr)50 Elinvar alloys results from a balance between intrinsic and residual resistivity. This effect is associated with atomic displacements from ideal lattice sites, which are caused by lattice thermal vibrations and chemical disorder-induced lattice distortions. It is further evidenced by a decrease in lattice distortion with temperature and changes in the electronic density of states. © 2025, CC BY.

关键词： Electronic density of states

Direct sampling method via Landweber iteration for an absorbing scatterer with a conductive boundary

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arXiv 2023年

作者： Ayala, Rafael Ceja Harris, Isaac Kleefeld, Andreas Department of Mathematics Purdue University West LafayetteIN47907 United States Forschungszentrum Jülich GmbH Jülich Supercomputing Centre Wilhelm-Johnen-Straße Jülich52425 Germany University of Applied Sciences Aachen Faculty of Medical Engineering and Technomathematics Heinrich-Mußmann-Str. 1 Jülich52428 Germany

In this paper, we consider the inverse shape problem of recovering isotropic scatterers with a conductive boundary condition. Here, we assume that the measured far-field data is known at a fixed wave number. Motivated by recent work, we study a new direct sampling indicator based on the Landweber iteration and the factorization method. Therefore, we prove the connection between these reconstruction methods. The method studied here falls under the category of qualitative reconstruction methods where an imaging function is used to recover the absorbing scatterer. We prove stability of our new imaging function as well as derive a discrepancy principle for recovering the regularization parameter. The theoretical results are verified with numerical examples to show how the reconstruction performs by the new Landweber direct sampling method. © 2023, CC BY.

关键词： Iterative methods

Detecting and approximating decision boundaries in low dimensional spaces

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arXiv 2023年

作者： Grajewski, Matthias Kleefeld, Andreas FH Aachen University of Applied Sciences Faculty of Medical Engineering Technomathematics Heinrich-Mußmann-Str. 1 Jülich52428 Germany Forschungszentrum Jülich GmbH Jülich Supercomputing Centre Wilhelm-Johnen-Str. Jülich52425 Germany Institute for Data-Driven Technologies FH Aachen University of Applied Sciences Heinrich-Mußmann-Str. 1 Jülich52428 Germany

A method for detecting and approximating fault lines or surfaces, respectively, or decision curves in two and three dimensions with guaranteed accuracy is presented. Reformulated as a classification problem, our method starts from a set of scattered points along with the corresponding classification algorithm to construct a representation of a decision curve by points with prescribed maximal distance to the true decision curve. Hereby, our algorithm ensures that the representing point set covers the decision curve in its entire extent and features local refinement based on the geometric properties of the decision curve. We demonstrate applications of our method to problems related to the detection of faults, to Multi-Criteria Decision Aid and, in combination with Kirsch’s factorization method, to solving an inverse acoustic scattering problem. In all applications we considered in this work, our method requires significantly less pointwise classifications than previously employed algorithms. © 2023, CC BY.

关键词： Fault detection

Non-planar snake gaits: from Stigmatic-starts to Sidewinding

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arXiv 2023年

作者： Charles, N. Chelakkot, R. Gazzola, M. Young, B. Mahadevan, L. Engineering and Applied Sciences Harvard University CambridgeMA02138 United States Department of Physics Indian Institute of Technology Bombay Mumbai400076 India Department of Mechanical Science and Engineering National Center for Supercomputing Applications Carl R. Woese Institute for Genomic Biology University of Illinois at Urbana-Champaign UrbanaIL United States Department of Anatomy A.T. Still University of Health Sciences Kirksville College of Osteopathic Medicine KirksvilleMO63501 United States Engineering and Applied Sciences Department of Physics Department of Organismic and Evolutionary Biology Harvard University CambridgeMA02138 United States

Of the vast variety of animal gaits, one of the most striking is the non-planar undulating motion of a sidewinder. But non-planar gaits are not limited to sidewinders. Here we report a new non-planar mode used as an escape strategy in juvenile anacondas (Eunectes notaeus). In the S-start, named for its eponymous shape, transient locomotion arises when the snake writhes and bends out of the plane while rolling forward about its midsection without slippage. To quantify our observations, we present a mathematical model for an active non-planar filament that interacts anisotropically with a frictional substrate and show that locomotion is due to a propagating localized pulse of a topological quantity, the link density. A two-dimensional phase space characterized by scaled body weight and muscular torque shows that relatively light juveniles are capable of S-starts but heavy adults are not, consistent with our experiments. Finally, we show that a periodic sequence of S-starts naturally leads to a sidewinding gait. All together, our characterization of a novel escape strategy in snakes highlights the role of topology in locomotion, provides a phase diagram for mode feasibility as a function of body size, and suggests a role for the S-start in the evolution of sidewinding. © 2023, CC BY.

关键词： Topology

On trajectories of complex-valued interior transmission eigenvalues

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arXiv 2022年

作者： Pieronek, Lukas Kleefeld, Andreas Karlsruhe Institute of Technology Institute for Applied and Numerical Mathematics Englerstr. 2 Karlsruhe76131 Germany Forschungszentrum Jülich GmbH Jülich Supercomputing Centre Wilhelm-Johnen-Str. Jülich52425 Germany University of Applied Sciences Aachen Faculty of Medical Engineering and Technomathematics Heinrich-Mußmann-Str. 1 Jülich52428 Germany

This paper investigates properties of complex-valued eigenvalue trajectories for the interior transmission problem parametrized by the index of refraction for homogeneous media. Our theoretical analysis for the unit disk shows that the only intersection points with the real axis, as well as the unique trajectorial limit points as the refractive index tends to infinity, are Dirichlet eigenvalues of the Laplacian. Complementing numerical experiments even give rise to an underlying one-to-one correspondence between Dirichlet eigenvalues of the Laplacian and complex-valued interior transmission eigenvalue trajectories. We also examine other scatterers than the disk for which similar numerical observations can be made. We summarize our results in a conjecture for general simply-connected scatterers. © 2022, CC BY.

关键词： Eigenvalues and eigenfunctions

Matrix-Valued LogSumExp Approximation for Colour Morphology

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arXiv 2024年

作者： Kahra, Marvin Breuß, Michael Kleefeld, Andreas Welk, Martin Institute for Mathematics Brandenburg University of Technology Cottbus-Senftenberg Cottbus03046 Germany Forschungszentrum Jülich GmbH Jülich Supercomputing Centre Wilhelm-Johnen-Straße Jülich52425 Germany University of Applied Sciences Aachen Faculty of Medical Engineering Technomathematics Heinrich-Mußmann-Str. 1 Jülich52428 Germany UMIT TIROL Private University for Health Sciences and Health Technology Eduard-Wallnöfer-Zentrum 1 Hall/Tyrol 6060 Hall Austria

Mathematical morphology is a part of image processing that uses a window that moves across the image to change certain pixels according to certain operations. The concepts of supremum and infimum play a crucial role here, but it proves challenging to define them generally for higher-dimensional data, such as colour representations. Numerous approaches have therefore been taken to solve this problem with certain compromises. In this paper we will analyse the construction of a new approach, which we have already presented experimentally in paper [15]. This is based on a method by Burgeth and Kleefeld [6], who regard the colours as symmetric 2 × 2 matrices and compare them by means of the Loewner order in a bi-cone through different suprema. However, we will replace the supremum with the LogExp approximation for the maximum instead. This allows us to transfer the associativity of the dilation from the one-dimensional case to the higher-dimensional case. In addition, we will investigate the minimality property and specify a relaxation to ensure that our approach is continuously dependent on the input *** Codes 68R01 © 2024, CC BY.

关键词： Mathematical morphology

Numerical Simulation of Radiatively driven Transonic Relativistic Jets

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arXiv 2024年

作者： Joshi, Raj Kishor Chattopadhyay, Indranil Tsokaros, Antonios Tripathi, Priyesh Kumar Manora Peak Nainital263001 India Department of Astronomy Astrophysics and Space Engineering Indian Institute of Technology Indore Khandwa Road Simrol453552 India Department of Physics Deen Dayal Upadhyaya Gorakhpur University Gorakhpur273009 India Department of Physics University of Illinois at Urbana-Champaign UrbanaIL61801 United States National Center for Supercomputing Applications University of Illinois at Urbana-Champaign UrbanaIL61801 United States Research Center for Astronomy and Applied Mathematics Academy of Athens Athens11527 Greece

We perform the numerical simulations of axisymmetric, relativistic, optically thin jets under the influence of the radiation field of an accretion disk. We show that starting from a very low injection velocity at the base, jets can be accelerated to relativistic terminal speeds when traveling through the radiation field. The jet gains momentum through the interaction with the radiation field. We use a relativistic equation of state for multi-species plasma, which self-consistently calculates the adiabatic index for the jet material. All the jet solutions obtained are transonic in nature. In addition to the acceleration of the jet to relativistic speeds, our results show that the radiation field also acts as a collimating agent. The jets remain well collimated under the effect of radiation pressure. We also show that if the jet starts with a rotational velocity, the radiation field will reduce the angular momentum of the jet beam. Copyright © 2024, The Authors. All rights reserved.

关键词： Equations of state

An Approach to Colour Morphological Supremum Formation using the LogSumExp Approximation

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arXiv 2023年

作者： Kahra, Marvin Breuß, Michael Kleefeld, Andreas Welk, Martin Institute for Mathematics Brandenburg University of Technology Cottbus-Senftenberg Cottbus03046 Germany Forschungszentrum Jülich GmbH Jülich Supercomputing Centre Wilhelm-Johnen-Straße Jülich52425 Germany University of Applied Sciences Aachen Faculty of Medical Engineering Technomathematics Heinrich-Mußmann-Straße 1 Jülich52428 Germany UMIT TIROL Private University for Health Sciences and Health Technology Eduard-Wallnöfer-Zentrum 1 Tyrol 6060 Hall Austria

Mathematical morphology is a part of image processing that has proven to be fruitful for numerous applications. Two main operations in mathematical morphology are dilation and erosion. These are based on the construction of a supremum or infimum with respect to an order over the tonal range in a certain section of the image. The tonal ordering can easily be realised in grey-scale morphology, and some morphological methods have been proposed for colour morphology. However, all of these have certain limitations. In this paper we present a novel approach to colour morphology extending upon previous work in the field based on the Loewner order. We propose to consider an approximation of the supremum by means of a log-sum exponentiation introduced by Maslov. We apply this to the embedding of an RGB image in a field of symmetric 2 × 2 matrices. In this way we obtain nearly isotropic matrices representing colours and the structural advantage of transitivity. In numerical experiments we highlight some remarkable properties of the proposed *** Codes 68R01 © 2023, CC BY.

关键词： Mathematical morphology