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The potential for electrifying industrial utility systems in existing chemical plants

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applied Energy 2025年 392卷

作者： Bielefeld, Svenja Cvetković, Miloš Ramírez, Andrea Engineering Systems and Services Department Faculty of Technology Policy and Management Delft University of Technology Delft Netherlands Electrical Sustainable Energy Department Faculty of Electrical Engineering Mathematics & Computer Science Delft University of Technology Delft Netherlands Department of Chemical Engineering Faculty of Applied Science Delft University of Technology Delft Netherlands

The electrification of utility systems in energy-intensive plants is a promising measure for decarbonising the chemical industry in the short term. However, with the increasing deployment of renewable energy sources, the variability of electricity prices will become a challenge for plants with continuous and constant energy demand. It is thus uncertain whether electrification can become financially viable. This work models the electrification of utility systems in combination with storage technologies for five chemical plants with existing fossil fuel-based utility generation and uses historical data as energy price scenarios. The results show that partial electrification is cost-effective when using electricity is cheaper than natural gas for more than 600 h. Regarding the portfolio of technologies, electric boilers are installed first, followed by thermal energy storage and batteries. Hydrogen is not cost-effective in any of the scenarios explored. This is independent of the type of plant, the available grid connection capacity, and the minimal load of existing fossil fuel-based utility generation. This work thus highlights the potential for electrifying industrial utility systems and the role that electric boilers and energy storage units can play in electrification. © 2025 The Author(s)

关键词： Chemical plants

Two-step solvent post-treatment on PTAA for highly efficient and stable inverted perovskite solar cells

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Photonics Research 2020年第10期8卷 I0002-I0012页

作者： YANG LI CHAO LIANG GAOPENG WANG JIELEI LI SHI CHEN SHIHE YANG CUICHUANG XING HUI PAN Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao SAR999078China Guangdong Key Laboratory of Nano-Micro Material Research School of Chemical Biology and BiotechnologyShenzhen Graduate SchoolPeking UniversityShenzhen 518055China Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of MacaoMacao SAR999078China

Modifying the surface of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)with toluene during the high-speed spin-coating process of dimethylformamide considerably improves the wettability and morphology of PTAA and results in improvement of the crystallinity and absorption of perovskite *** hole mobility and ohm contact have also been improved *** with these improved parameters,inverted perovskite solar cells with high efficiency of 19.13%and long-term stability could be achieved,which are much better than those with untreated ***,our devices can keep 88.4%of the initial power conversion efficicncy after 30 days of storage in ambient air.

关键词： film. perovskite ambient

Length Scales in Brownian yet Non-Gaussian Dynamics

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Physical Review X 2021年第3期11卷 031002-031002页

作者： José M. Miotto Simone Pigolotti Aleksei V. Chechkin Sándalo Roldán-Vargas Leiden Institute of Advanced Computer Science 2333 CA Leiden Netherlands Biological Complexity Unit Okinawa Institute for Science and Technology and Graduate University Onna Okinawa 904-0495 Japan Institute for Physics and Astronomy University of Potsdam 14476 Potsdam-Golm Germany Akhiezer Institute for Theoretical Physics Kharkov 61108 Ukraine Max Planck Institute for the Physics of Complex Systems 01187 Dresden Germany Department of Applied Physics Faculty of Sciences University of Granada 18071 Granada Spain

According to the classical theory of Brownian motion, the mean-squared displacement of diffusing particles evolves linearly with time, whereas the distribution of their displacements is Gaussian. However, recent experiments on mesoscopic particle systems have discovered Brownian yet non-Gaussian regimes where diffusion coexists with an exponential tail in the distribution of displacements. Here we show that, contrary to the present theoretical understanding, the length scale λ associated with this exponential distribution does not necessarily scale in a diffusive way. Simulations of Lennard-Jones systems reveal a behavior λ∼t1/3 in three dimensions and λ∼t1/2 in two dimensions. We propose a scaling theory based on the idea of hopping motion to explain this result. In contrast, simulations of a tetrahedral gelling system, where particles interact by a nonisotropic potential, yield a temperature-dependent scaling of λ. We interpret this behavior in terms of an intermittent hopping motion. Our findings link the Brownian yet non-Gaussian phenomenon with generic features of glassy dynamics and open new experimental perspectives on the class of molecular and supramolecular systems whose dynamics is ruled by rare events.

关键词： Brownian motion Collective behavior Diffusion Gels Glassy systems Liquids Extreme event statistics Molecular dynamics

SPECTRAL NON-CONCENTRATION NEAR THE TOP FOR UNIMODULAR RANDOM GRAPHS

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arXiv 2024年

作者： Fraczyk, Mikolaj Hayes, Ben Sudan, Madhu Zhao, Yufei Faculty of Mathematics and Computer Science Jagiellonian University ul. Lojasiewicza 6 Kraków30-348 Poland Department of Mathematics University of Virginia Kerchof Hall 141 Cabell Drive CharlottesvilleVA22904 United States School of Engineering and Applied Sciences Harvard University CambridgeMA United States Massachusetts Institute of Technology CambridgeMA United States

In recent work on equiangular lines, Jiang, Tidor, Yuan, Zhang, and Zhao showed that a connected bounded degree graph has sublinear second eigenvalue multiplicity. More generally they show that there cannot be too many eigenvalues near the top of the spectrum. We extend this result to infinite unimodular random graphs. As a corollary, the spectral distribution of the adjacency operator cannot have an atom at the top. For an infinite regular expander, we deduce that the singularity of the spectral measure at the top satisfies µG[(1 − θ)ρ, ρ] θc for some constant c > 0, where ρ is the spectral radius of the adjacency operator of the graph. This implies new general estimates on the return probabilities of random walks. Copyright © 2024, The Authors. All rights reserved.

关键词： Eigenvalues and eigenfunctions

Eliminating Crossings in Ordered Graphs

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arXiv 2024年

作者： Agrawal, Akanksha Cabello, Sergio Kaufmann, Michael Saurabh, Saket Sharma, Roohani Uno, Yushi Wolff, Alexander Indian Institute of Technology Chennai Madras India Faculty of Mathematics and Physics University of Ljubljana Ljubljana Slovenia Institute of Mathematics Physics and Mechanics Ljubljana Slovenia Department of Computer Science Tübingen University Tübingen Germany Institute of Mathematical Sciences Chennai India University of Bergen Bergen Norway Graduate School of Informatics Osaka Metropolitan University Sakai Japan Universität Würzburg Würzburg Germany

Drawing a graph in the plane with as few crossings as possible is one of the central problems in graph drawing and computational geometry. Another option is to remove the smallest number of vertices or edges such that the remaining graph can be drawn without crossings. We study both problems in a book-embedding setting for ordered graphs, that is, graphs with a fixed vertex order. In this setting, the vertices lie on a straight line, called the spine, in the given order, and each edge must be drawn on one of several pages of a book such that every edge has at most a fixed number of crossings. In book embeddings, there is another way to reduce or avoid crossings;namely by using more pages. The minimum number of pages needed to draw an ordered graph without any crossings is its (fixed-vertex-order) page number. We show that the page number of an ordered graph with n vertices and m edges can be computed in 2m nO(1) time. An O(log n)-approximation of this number can be computed efficiently. We can decide in 2O(d √k log(d+k)) nO(1) time whether it suffices to delete k edges of an ordered graph to obtain a d-planar layout (where every edge crosses at most d other edges) on one page. As an additional parameter, we consider the size h of a hitting set, that is, a set of points on the spine such that every edge, seen as an open interval, contains at least one of the points. For h = 1, we can efficiently compute the minimum number of edges whose deletion yields fixed-vertex-order page number p. For h >1, we give an XP algorithm with respect to h + p. Finally, we consider spine+t-track drawings, where some but not all vertices lie on the spine. The vertex order on the spine is given;we must map every vertex that does not lie on the spine to one of t tracks, each of which is a straight line on a separate page, parallel to the spine. In this setting, we can minimize in 2n nO(1) time either the number of crossings or, if we disallow crossings, the number of tracks. © 2024, CC BY.

关键词： Computational geometry

Corrigendum to “Developing polymer nanocomposite films of ZnO/NiFe 2 O 4 nanohybrids, polyvinyl pyrrolidone, and chitosan for flexible electromagnetic applications and energy storage devices” [Ceram. Int. 50 (2024) 28794–2880]

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Ceramics International 2025年

作者： Hessa A. Alsalmah Adel Bandar Alruqi Omer Nur A. Rajeh Department of Physics College of Science Imam Mohammad Ibn Saud Islamic University (IMSIU) Riyadh 11623 Saudi Arabia Department of Physics Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Department of Science and Technology Linkoping University Campus Norrkoping SE-60174 Norrkoping Sweden Physics Department Faculty of Applied Science Amran University Sana’a Yemen

Visualizing Quantum Circuit Probability estimating computational action for quantum program synthesis

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arXiv 2023年

作者： Bach, Bao Gia Kundu, Akash Acharya, Tamal Sarkar, Aritra Faculty of Computer Science and Engineering Ho Chi Minh City University of Technology Viet Nam Viet Nam Joint Doctoral School Silesian University of Technology Gliwice Poland Institute of Theoretical and Applied Informatics Polish Academy of Sciences Gliwice Poland Independent Researcher Bengaluru India Quantum Machine Learning Research group Quantum Computing Division QuTech Netherlands Quantum Intelligence Research team Department of Quantum & Computer Engineering Delft University of Technology Netherlands

This research applies concepts from algorithmic probability to Boolean and quantum combinatorial logic circuits. A tutorial-style introduction to states and various notions of the complexity of states are presented. Thereafter, the probability of states in the circuit model of computation is defined. Classical and quantum gate sets are compared to select some characteristic sets. The reachability and expressibility in a space-time-bounded setting for these gate sets are enumerated and visualized. These results are studied in terms of computational resources, universality and quantum behavior. The article suggests how applications like geometric quantum machine learning, novel quantum algorithm synthesis and quantum artificial general intelligence can benefit by studying circuit probabilities. © 2023, CC BY-NC-SA.

关键词： Machine learning

Bounding and Computing Obstacle Numbers of Graphs

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arXiv 2022年

作者： Balko, Martin Chaplick, Steven Ganian, Robert Gupta, Siddharth Hoffmann, Michael Valtr, Pavel Wolff, Alexander Department of Applied Mathematics Faculty of Mathematics and Physics Charles University Czech Republic Maastricht University Netherlands Institute of Logic and Computation Technische Universität Wien Austria Department of Computer Science & Information Systems BITS Pilani Goa Campus India Department of Computer Science ETH Zürich Switzerland Institut für Informatik Universität Würzburg Germany

An obstacle representation of a graph G consists of a set of pairwise disjoint simply-connected closed regions and a one-to-one mapping of the vertices of G to points such that two vertices are adjacent in G if and only if the line segment connecting the two corresponding points does not intersect any obstacle. The obstacle number of a graph is the smallest number of obstacles in an obstacle representation of the graph in the plane such that all obstacles are simple polygons. It is known that the obstacle number of each n-vertex graph is O(nlog n) [Balko, Cibulka, and Valtr, 2018] and that there are n-vertex graphs whose obstacle number is Ω(n/(log log n)2) [Dujmović and Morin, 2015]. We improve this lower bound to Ω(n/log log n) for simple polygons and to Ω(n) for convex polygons. To obtain these stronger bounds, we improve known estimates on the number of n-vertex graphs with bounded obstacle number, solving a conjecture by Dujmović and Morin. We also show that if the drawing of some n-vertex graph is given as part of the input, then for some drawings Ω(n2) obstacles are required to turn them into an obstacle representation of the graph. Our bounds are asymptotically tight in several instances. We complement these combinatorial bounds by two complexity results. First, we show that computing the obstacle number of a graph G is fixed-parameter tractable in the vertex cover number of G. Second, we show that, given a graph G and a simple polygon P, it is NP-hard to decide whether G admits an obstacle representation using P as the only obstacle. © 2022, CC BY.

关键词： Graph theory

An electrical model characterization of an electronic nose chemical sensor using a programmable system-on-a-chip based AFE

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An electrical model characterization of an electronic nose c...

International Young Engineers Forum (YEF-ECE)

作者： Joã o J. M. Santos Susana I. C. J. Palma Carina Esteves Hugo Gamboa Joã o Pedro Oliveira Ana C. A. Roque Department of Electrical and Computer Engineering NOVA School of Science and Technology NOVA University of Lisbon Caparica Portugal Associate Laboratory i4HB &#x2013 Institute for Health and Bioeconomy NOVA School of Science and Technology NOVA University of Lisbon Caparica Portugal UCIBIO &#x2013 Applied Molecular Biosciences Unit Department of Chemistry NOVA School of Science and Technology NOVA University of Lisbon Caparica Portugal LIBPhys - Laboratory for Instrumentation Biomedical Engineering and Radiation Physics NOVA School of Science and Technology NOVA University of Lisbon Caparica Portugal Center for Technology and Systems (CTS) &#x2013 UNINOVA NOVA School of Science and Technology NOVA University of Lisbon Caparica Portugal

ISBN: (数字)9781665467315

ISBN: (纸本)9781665467322

The diagnosis of many diseases involves invasive detection methods, which are both painful and stressing for patients. In the last decades, the ever-growing development in electronic nose (E-Nose) technology made them great candidates for non-invasive disease detection methods. Such devices mimic the human olfactory system through a set of sensors which produce signals that can be associated with diseases. Recently, a class of low-cost and innovative ionogel sensors, developed by our group demonstrated their full applicability in E-Nose systems, opening a new and promising approach to the field. However, the operation of such sensor needs a background calibration phase which relies on the correct characterization and parameterization of the corresponding electrical sensor *** paper proposes a model characterization methodology based on a set of frequency responses acquisitions of the sensor, under several humidity conditions. To obtain a flexible acquisition tool capable of acquiring accurate results, an analog front-end (AFE) circuit to interface with the interdigitated electrode (IDE) sensors is presented. Such AFE circuit is fully implemented using a programmable system-on-a-chip (PSoC), helping to reduce system size and cost. Lastly, a comparison between the electrical model and data acquired with the proposed system is presented.

关键词： Electrodes Chemical sensors Humidity Sensor phenomena and characterization Electronic noses Sensor systems Sensors