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Enhanced activity and durability of FeCoCrMoCbY nanoglass in acidic hydrogen evolution reaction

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Journal of Materials Science & Technology 2024年第3期170卷 212-220页

作者： Mengyang Yan Shuangqin Chen Shangshu Wu Xuechun Zhou Shu Fu Di Wang Christian Kübel horst Hahn Si Lan Tao Feng Herbert Gleiter Institute of Nanoscience School of Material Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Institute of Nanotechnology Karlsruhe Institute of TechnologyKarlsruhe 76021Germany

In the present work,a multi-element nanoglass(m-NG)of FeCoCrMoCbY is obtained first time by the laser ablation combined with inert gas condensation(laser-IGC)*** with the conventional rapid-quenched metallic glass(MG)with identical composition,the Fe-based m-NG demonstrates a superior performance as a self-supported electrocatalyst for hydrogen evolution reaction(HER)in acidic *** enhanced HER activity of m-NG is proposed to be closely related to its high en-ergy states,which is originated from the unique inhomogeneous nanostructures with a high density of low-coordinated ***,the Fe-based m-NG exhibits an outstanding comprehensive catalytic performance even beyond the commercial Pt/C catalyst in long-term test due to its self-optimization *** work not only opens the way to the preparation of m-NGs by the novel laser-IGC technique,but also makes a great contribution to developing low-cost,high-efficient,and super-durable HER electrocat-alysts in acidic environment.

关键词： Nanoglass Inert gas condensations High energy states Hydrogen evolution reactions

Tracking moving magnetic features in the photosphere

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1737-1748页

作者： bchner Jrg Max-Planck-Institut fr Sonnensystemforschung

This research aims for an objective identification, tracking, and a statistical analysis of the Moving Magnetic Features (MMFs) around sunspots using SOHO/MDI high-resolution magnetograms. To this end, we develop a computerized tracking program and study the motion and magnetism of the outflows of MMFs around 26 sunspots. Our method locates 4-27 MMFs per hour, with higher counts for large sunspots. We differentiate MMFs into type α that have a polarity opposite to the parent sunspots, and type β that share the sunspot's polarity. These sunspots' MMF subsets exhibit a wide range of central tendencies which have distinctive correlations with the sunspots. In general, α-MMFs emerge farther from the sunspot, carry less flux, and move faster than β-MMFs. The typical α/β-MMFs emerge at 2.2 - 8.1/0.1 - 3.2 Mm outside the penumbra limb, with lifetimes of 1.1 - 3.1/1.3 - 2.0 h. They are 1.1 - 6.6/1.4 - 3.6 Mm2 in area and carry 1.4 - 12.5/4.8 - 11.4 ×1018 Mx of flux. They travel a distance of 2.7 - 5.9/2.8 - 3.6 Mm with the speed of 0.5 - 0.9/0.4 - 0.7 km/s. Compared to the α-MMFs produced by large sunspots, those of small spots are smaller. They emerge closer to sunspot, move farther, live longer, and carry less flux. β-MMFs show much less correlation with the sunspots. The flux outflow carried by the MMFs ranges from 0.2 to 8.3 × 1019Mx· h-1 and does not show obvious correlation with the sunspots' evolution. The frequency distributions of the MMFs' distance traveled, area, and flux are exponential. This suggests the existence of numerous small, weak, and short-timescale magnetic objects which might contribute to the sunspot flux outflow.

关键词： sun activity magnetic fields photosphere sunspots moat moving magnetic features

black hole shadows in Einstein-bel-Robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： b.Hamil b.C.Lütfüoğlu Laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-bel-Robinson (EbR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EbR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-bel-Robinson gravity plasma

Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： M.b.KIRKHAM Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the Moon or Mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the Moon and Mars.

关键词： soils soil bases

Water Vapor Information from Satellite and Its Applications

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Advances in Atmospheric Sciences 2024年第1期41卷 188-189页

作者： b.J.SOHN School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle because it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

CompactChain:an efficient stateless chain for UTXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： b Swaroopa REDDY T Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UTXO(Unspent Transaction Output)based blockchain systems into two RSA *** first accumulator is called Transaction Output(TXO)commitment which represents the TXO *** second one is called Spent Transaction Output(STXO)commitment which represents the STXO *** this work,we discuss three algorithms:(i)To update the TXO and STXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)To prove the transaction’s validity by providing a membership witness in TXO commitment and non-membership witness against STXO commitment for a coin being spent by a user;(iii)To update the witness for the coin that is not yet spent;The experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(Transactions per second(TPS)).

关键词： stateless blockchain RSA Accumulator STXO commitment TXO commitment UTXO Non-interactive Proof of Exponentiation(NI-PoE) Transactions per second(TPS)

Extended quantum molecular dynamics model predicts new breathing modes in 36Ar bubble nuclei

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Nuclear Science and Techniques 2024年第10期35卷 268-270页

作者： Joseph b.Natowitz Department of Chemistry and Cyclotron Institute Texas A&M UniversityCollege Station

In theoretical investigations of36Ar published by Ge Ren et al.（Phys Lett b 138990,2024）,36Ar bubble nuclei,char acterized by central density depletions,were studied using the extended quantum molecular dynamics *** novel density distributions—microbubble,bubble,and cluster resonances—were identified,each showing distinc spectral signatures in the gamma-ray decay spectrum o the isoscalar monopole ***,the oscillation frequency of the bubble mode mirrors macroscopic bubble dynamics,bridging classical and quantum phenomena in atomic *** exploration of exotic nuclei,driven by advances in large-scale radioactive ion beam facilities,reshapes nuclea physics,particularly as regards the complex structures and behaviors of atomic *** structures and deforma tions[1–3]challenge traditional models.

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Closing the Experiment-Modeling-Perturbation Loop in Whole-brain Neuroscience

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Neuroscience bulletin 2024年第8期40卷 1212-1214页

作者： Misha b.Ahrens Janelia Research Campus Howard Hughes Medical InstituteAshburnVAUSA

Understanding the mechanisms by which the central nervous system processes information,forms memories,makes decisions,and executes actions is a challenging *** is an interdisciplinary field in which cell biology,anatomy,network theory,and other scientific disciplines come together to jointly push our knowledge of brain function forward.

关键词： execute knowledge jointly

Quantized autoencoder(QAE)intrusion detection system for anomaly detection in resource-constrained loT devices using RT-loT2022 dataset

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Cybersecurity 2024年第2期7卷 13-27页

作者： b S Sharmila Rohini Nagapadma Depatment of Electronics and Communication Engineering The National Institute of EngineeringMysoreKarnataka 570008India

In recent years,many researchers focused on unsupervised learning for network anomaly detection in edge devices to identify *** deployment of the unsupervised autoencoder model is computationally expensive in resource-constrained edge *** study proposes quantized autoencoder(QAE)model for intrusion detection systems to detect *** is an optimization model derived from autoencoders that incorporate pruning,clustering,and integer quantization *** autoencoder uint8(QAE-u8)and quantized autoencoder float16(QAE-f16)are two variants of QAE built to deploy computationally expensive Al models into Edge ***,we have generated a Real-Time Internet of Things 2022 dataset for normal and attack *** autoencoder model operates on normal traffic during the training *** same model is then used to reconstruct anomaly traffic under the assumption that the reconstruction error(RE)of the anomaly will be high,which helps to identify the ***,we study the performance of the autoencoders,QAE-u8,and QAE-f16 using accuracy,precision,recall,and F1 score through an extensive experimental *** showed that QAE-u8 outperforms all other models with a reduction of 70.01%in average memory utilization,92.23%in memory size compression,and 27.94%in peak CPU ***,the proposed QAE-u8 model is more suitable for deployment on resource-constrained IoT edge devices.

关键词： IoT constrained system