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Chirality enables thermal magnon transistors

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 161-166页

作者： Tao Yu Chengyuan Cai Gerrit e.w.Bauer School of Physics Huazhong University of Science and TechnologyWuhan 430074China .wPI-AIMR and Institute for Materials Research and SCIS Tohoku UniversitySendai 980-8577Japan Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China

we report a theory of thermal spin pumping into proximity magnets under a transverse-bias-driven heat flow of magnons in magnetic films when the dipolar coupling to the magnetic gate is tuned to be “chiral”. while there is no rectification of the magnon current in the film, we predict that chirality diverts a large percentage(50% for perfect chirality) of it into the gate. This transverse thermal spin pumping effect can be controlled by rotating the film magnetization and may help manage the heat flow in future magnonic circuits.

关键词： magnon chirality quantum transport transistor

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTlU İsmail e.KIlIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

Supramolecular Polymerization of Hydrogen-Bonded Trimers in Bulk and Aqueous Medium

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CCS Chemistry 2024年第6期6卷 1458-1465页

作者： Freek V.de Graaf Stef A.H.Jansen Sandra M.C.Schoenmakers Bas van Genabeek Marle e.J.Vleugels Bart w.l.van den Bersselaar e.w.Meijer Ghislaine Vantomme Institute for Complex Molecular Systems Laboratory of Macromolecular and Organic ChemistryEindhoven University of Technology5600 MBEindhoven School of Chemistry and RNA Institute University of New South WalesSydneyNew South Wales 2052

Synthetic molecules that form functional noncovalent assemblies in water have received much attention for their potential applications as *** this work,we introduce a novel water-compatible monomer based on the phthalhydrazide moiety that assembles into hydrogen-bonded trimeric *** bulk,the material exhibits a cylindrical nanostructure in the liquid-crystalline phase at elevated temperatures,morphologically distinct from the crystalline lamellar *** water,these molecules effectively form cylinders in a one-dimensional fashion,yielding fibrous *** formation of these supramolecular polymers follows a cooperative mechanism,as evidenced by denaturation *** trimerized pattern represents a new category of aqueous su pramolecular polymers with future prospects for functional complex molecular systems.

关键词： noncovalent chemistry supramolecular polymers hydrogen bonding cooperativity nanostructure

efficient fidelity estimation: alternative derivation and related applications

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Communications in Theoretical Physics 2024年第9期76卷 18-22页

作者： Diego S Starke Marcos l w Basso Jonas Maziero Physics Department Center for Natural and Exact Sciences Federal University of Santa Maria Center for Natural and Human Sciences Federal University of ABC Avenue of the States

In[***.A 107 012427 (2023)],Baldwin and Jones prove that Uhlmann–Jozsa’s fidelity between two quantum statesρandσ,i.e.,■,can be written in a simplified form as ■.In this article,we give an alternative proof of this result,using a function power series expansion and the properties of the trace *** approach not only reinforces the validity of the simplified expression but also facilitates the exploration of novel dissimilarity functions for quantum states and more complex trace functions of density operators.

关键词： Chebyshev polynomials efficient fidelity estimation Rényi entropy Ulhmann-Jozsa fidelity

effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： F.Animah C.Keles w.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber Canopy air curtain Silica

Highly enhanced UV absorption and light emission of monolayer wS_(2)through hybridization with Ti_(2)N MXene quantum dots and g-C_(3)N_(4)quantum dots

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Opto-electronic Advances 2024年第6期7卷 31-39页

作者： Anir S.Sharbirin Rebekah e.Kong wendy B.Mato Trang Thu Tran eunji lee Jolene w.P.Khor Afrizal l.Fadli Jeongyong Kim Department of energy Science Sungkyunkwan UniversitySuwon 16419Republic of Korea

Two-dimensional(2D)transition metal dichalcogenides(TMD)are atomically thin semiconductors with promising optoelectronic applications across the visible ***,their intrinsically weak light absorption and the low photoluminescence quantum yield(PlQY)restrict their performance and potential use,especially in ultraviolet(UV)wavelength light *** dots(QD)derived from 2D materials(2D/QD)provide efficient light absorption and emission of which energy can be tuned for desirable light *** this study,we greatly enhanced the photon absorption and PlQY of monolayer(1l)tungsten disulfide(wS_(2))in the UV range via hybridization with 2D/QD,particularly titanium nitride MXene QD(Ti_(2)N MQD)and graphitic carbon nitride QD(GCNQD).with the hybridization of MQD or GCNQD,1lwS_(2)showed a maximum Pl enhancement by 15 times with 300 nm wavelength excitation,while no noticeable enhancement was observed when the excitation photon energy was less than the bandgap of the QD,indicating that UV absorption by the QD played a crucial role in enhancing the light emission of 1l-wS_(2)in our 0D/2D hybrid *** findings present a convenient method for enhancing the photo-response of 1l-wS_(2)to UV light and offer exciting possibilities for harvesting UV energy using 1l-TMD.

关键词： monolayer TMD wS_(2) 2D-derived quantum dots UV absorption energy transfer

when Fleeing Matters:Differences in escape Behaviours of Three Northeast Asian Anurans

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Asian Herpetological Research 2024年第1期15卷 41-48页

作者： Yoonjung YI Zoljargal PUReVDORJ Irina MASlOVA Yikweon JANG Amaël BORZÉe laboratory of Animal Behaviour and Conservation College of Life SciencesNanjing Forestry UniversityNanjing 210037JiangsuChina Division of ecoScience and Department of life Sciences Ewha Womans UniversitySeoul 03760Republic of Korea Department of Biology School of MathematicsMongolian State University of EducationUlaanbaatar 210648Mongolia Department of Forest and environmental Resources Chungnam National UniversityDaejeon 34134Republic of Korea Federal Scientific Center of the east Asia Terrestrial Biodiversity Far Eastern Branch of Russian Academy of SciencesVladivostok 690022Russia

Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of *** species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body ***,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR *** examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body *** raddei and *** had a longer FID than ***,and *** also had a longer DF than *** trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all *** suggests that the treefrog *** used a strategy to stay immobile even when they were detected,and the toad *** reacted quicker and more sensitively to predators despite the presence of *** *** had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three *** results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.

关键词： amphibian distance fled escape behaviour flight initiation distance predation

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On B(5,20) 2-Groups

AlGeBRA COllOQUIUM 2024年第3期31卷 429-440页

作者： Alhassan, e. A. Tan, Y. l. li, Y. Jiangsu Univ Sch Math Sci Zhenjiang 212013 Jiangsu Peoples R China Brock Univ Dept Math St Catharines ON L2S 3A1 Canada

A finite group G is said to be a B( n, k) group if for any n-element subset { a(1) , & mldr; , a(n) } of G, | { a(i) a(j )| 1 <= i, j <= n } | <= k . It is of interest to characterize the structure of B( n, k) groups ... 详细信息

A finite group G is said to be a B( n, k) group if for any n-element subset { a(1) , & mldr; , a(n) } of G, | { a(i) a(j )| 1 erest to characterize the structure of B( n, k) groups for n( n+1 ) /2 e B( 5, k) groups for 15 e been investigated by several authors. In this paper, we give a complete characterization of B( 5, 20) 2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n, k) groups small squaring property central extension GAP

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt C.M.Saporetti l.C.Oliveira e.Pereira Department of Computational and Applied Mechanics Federal University of Juiz de Fora Department of Computational Modeling Polytechnic Institute Rio de Janeiro State University Petrobras Department of Stratigraphy and Paleontology Rio de Janeiro State University

Rock samples' TOC content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In light of these efforts, the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOC. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. Core samples from the YuDong-Nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOC. The results show that, independent of the metaheuristic used to guide the model selection, optimized extreme learning machines attained the best performance scores according to six metrics. Such hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning evolutionary algorithms Geology