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Microstructure and magnetocaloric properties of melt-extracted SmGdDyCoAl high-entropy amorphous microwires

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Rare Metals 2024年第3期43卷 1234-1242页

作者： Shi-Jie wei Hong-Xian shen Lun-Yong Zhang Lin Luo Xin-Xing Tang Jian-Fei Sun Xiao-Qing Li School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China Applied Materials Physics Department of Materials Science and EngineeringKTH-Royal Institute of Technology10044StockholmSweden

This paper presents a systematic investigation of the microstructure and magnetocaloric properties of melt-extracted Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)high-entropy *** fabricated wires exhibited an amorphous structure,and the temperature interval of the undercooled liquid AT was 45 *** microwires underwent a second-order magnetic transition from a ferromagnetic to a paramagnetic state near the Curie temperature(T_(C)=52 K),The maximum magnetic entropy change(-ΔS_M^(max)),the relative cooling power and the refrigeration capacity reached 6.34 J·kg^(-1)·K^(-1).422.09 J·kg^(-1)and 332.94 J·kg^(-1),respectively,under a magnetic field change of 5 *** addition,the temperature-averaged entropy changes with two temperature lifts(3 and 10 K)were 6.32 and 6.27 J·kg^(-1)·K^(-1),*** good magnetocalorie performance highlights the significant potential for the Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)microwires to be used as magnetic refrigerant materials in low-temperature region *** work will serve as a valuable reference for future investigations on low-temperature high-entropy magnetocaloric materials.

关键词： Melt-extraction High-entropy amorphous microwires Magnetocaloric effect Magnetic refrigeration

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Physics of cavitation near particles

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Journal of Hydrodynamics 2024年第1期36卷 102-118页

作者： Jia-xin Yu Xiao-yu Wang Jun-wei shen Jin-sen Hu Xiang-qing Zhang Da-qing He Yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The combined effect of cavitation and silt abrasion presents a great challenge and threat to secure the operation and the efficiency of hydraulic machineries working in sediment-laden *** present paper critically reviews the current research progress on the interaction mechanisms of the bubbles and the ***,the analytical models including boundary treatment methods for predicting the jet dynamics of the bubble collapse near particles are ***,the bubble collapsing dynamics,jet dynamics and shock wave characteristics near particles are revealed both experimentally and ***,the bubble-particle-wall system is investigated with a focus on microjets.

关键词： Cavitation bubble particle jet shock wave

Sulfur doped iron-nitrogen-hard carbon nanosheets as efficient and robust noble metal-free catalysts for oxygen reduction reaction in PEMFC

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Journal of Energy Chemistry 2024年第2期89卷 422-433,I0010页

作者： Bin Liu Jiawang Li Bowen Yan Qi wei Xingyu Wen Huarui Xie Huan He Pei Kang shen Zhi Qun Tian Collaborative Innovation Center of Sustainable Energy Materials School of Physical Science and TechnologyGuangxi UniversityGuangxi Key Laboratory of Electrochemical Energy MaterialsState Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresNanning 530004GuangxiChina

Transition metal-nitrogen-carbon(M-N-C)as a promising substitute for the conventional noble metalbased catalyst still suffers from low activity and durability for oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).To tackle the issue,herein,a new type of sulfur-doped ironnitrogen-hard carbon(S-Fe-N-HC)nanosheets with high activity and durability in acid media were developed by using a newly synthesized precursor of amide-based polymer with Fe ions based on copolymerizing two monomers of 2,5-thiophene dicarboxylic acid(TDA)as S source and 1,8-diaminonaphthalene(DAN)as N source via an amination *** as-synthesized S-Fe-N-HC features highly dispersed atomic Fe Nxmoieties embedded into rich thiophene-S doped hard carbon nanosheets filled with highly twisted graphite-like microcrystals,which is distinguished from the majority of M-N-C with soft or graphitic carbon *** unique characteristics endow S-Fe-N-HC with high ORR activity and outstanding durability in 0.5 M H_(2)SO_(4).Its initial half-wave potential is 0.80 V and the corresponding loss is only 21 m V after 30,000 ***,its practical PEMFC performance is a maximum power output of 628.0 mW cm^(-2)and a slight power density loss is 83.0 m W cm^(-2)after 200-cycle practical ***,theoretical calculation shows that the activity of Fe Nxmoieties on ORR can be further enhanced by sulfur doping at meta-site near FeN_(4)*** results evidently demonstrate that the dual effect of hard carbon substrate and S doping derived from the precursor platform of amid-polymers can effectively enhance the activity and durability of Fe-N-C catalysts,providing a new guidance for developing advanced M-N-C catalysts for ORR.

关键词： Transition metal-nitrogen-carbon Oxygen reduction reaction Hard carbon Amide based polymer reaction Proton exchange membrane cells

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Optimizing the Diameter of Plugging Balls in Deep Shale Gas Wells

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Fluid Dynamics & Materials Processing 2024年第3期20卷 609-624页

作者： Yi Song Zheyu Hu Cheng shen Lan Ren Xingwu guo Ran Lin Kun Wang Zhiyong Zhao Shale Gas Research Institute PetroChina Southwest Oil&Gasfield CompanyChengdu610056China State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China National Pipe Network Group Sichuan East Natural Gas Transmission Pipeline Co. Ltd.Wuhan430205China Fracturing Acidizing Company Downhole Operation Company of Chuanqing Drilling Engineering Co.Ltd.Chengdu610213China

Deep shale gas reserves that have been fractured typically have many relatively close perforation holes. Due to theproximity of each fracture during the formation of the fracture network, there is significant stress interference,which results in uneven fracture propagation. It is common practice to use “balls” to temporarily plug fractureopenings in order to lessen liquid intake and achieve uniform propagation in each cluster. In this study, a diameteroptimization model is introduced for these plugging balls based on a multi-cluster fracture propagationmodel and a perforation dynamic abrasion model. This approach relies on proper consideration of the multiphasenature of the considered problem and the interaction force between the involved fluid and solid phases. Accordingly,it can take into account the behavior of the gradually changing hole diameter due to proppant continuousperforation erosion. Moreover, it can provide useful information about the fluid-dynamic behavior of the consideredsystem before and after plugging. It is shown that when the diameter of the temporary plugging ball is1.2 times that of the perforation hole, the perforation holes of each cluster can be effectively blocked.

关键词： Deep shale gas fracture propagation fluid mechanics fluid-solid coupling perforation hole abrasion

Failure mechanism and simulation for long run-out of the catastrophic rock landslide in the Shanyang Vanadium Mine,China

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Journal of Mountain Science 2024年第9期21卷 2905-2917页

作者： LIU Yinpeng Mumtaz HAIDER David-darnor LAWRENCE LI Tonglu shen wei LI Ping College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Observation and Research Station of Water Cycle and Geological Environment for the Chinese Loess Plateau Ministry of EducationZhengning 745399China

On 12th August 2015,a massive rapid long run-out rock landslide occurred in the Shanyang Vanadium Mine in Shaanxi Province,China,which claimed the lives of 65 *** heavy rainfalls,earthquakes,and mining blasts were recorded before the ***,the failure mechanism and the cause of the long run-out movement are always in *** this paper,we conducted a detailed field investigation,laboratory tests,block theory analysis,and numerical simulation to investigate the failure and long run-out mechanisms of the *** field investigation results show that the source material of the rock landslide is a huge dolomite wedge block bedding on siliceous shale *** compression tests indicate that the uniaxial compression strength of the intact dolomite is 130-140MPa and the dolomite shows a brittle failure *** to the progressive downward erosion of the gully,the dolomite rock bridge at the slope toe became *** the compression stress in the dolomite bridge increased to surpass its strength,the brittle failure of the bridge *** huge potential energy was released following the disintegration of the landslide,which led to the high acceleration of this rock *** 3D discrete element simulation results suggest that the low intergranular friction contributes to the long run-out movement of this rock landslide.

关键词： Rock landslide Gully erosion Long run-out Wedge block Discrete element method

Thermodynamic performance of a cryogenic energy storage system based on natural gas liquefaction

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Energy Storage and Saving 2024年第1期3卷 23-29页

作者： Xiaoqiao Qin Hongbo Tan wei shen Na Wen Yu Sun Department of Refrigeration and Cryogenic Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China Yingde Gases(Shanghai)Group Company Limited Shanghai210035China Technical Institute of Physics and Chemistry CASBeijing100190China

Cryogenic energy storage(CES)is a viable method for grid-scale electrical energy *** the high energy density and mature application of liquefied natural gas(LNG),we proposed an LNG cryogenic energy storage(LNGES)system.A steady-state process model of the LNGES system was established using Aspen *** effects of the natural gas composition and key operating parameters such as the charging pressure,discharging pressure,throttling temperature,and liquid storage pressure on the system performance were investigated.A multi-parameter genetic algorithm model built using the MATLAB software was used to optimize the LNGES system to optimize the round-trip efficiency(RTE).Then,an exergy analysis of the optimal configuration was *** results suggested that the LNGES system could achieve optimal RTE and exergy efficiency values of 60.14%and 71.64%,*** destruction mainly occurred during the compression,throttling,expansion,and heat *** proposed LNGES system could be a promising candidate for the large-scale application of CES technology in power grids and gas networks.

关键词： Cryogenic energy storage Liquefied natural gas Genetic algorithm optimization Round-trip efficiency Exergy analysis

Ferroelectric perovskite PbTiO3for advanced photocatalysis

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Rare Metals 2024年第9期43卷 4038-4055页

作者： Shuang Zhao Shi-Shi shen Lu Han Bo-Chao Tian Na Li wei Chen Xi-Bao Li School of Materials and Metallurgy University of Science andTechnology Liaoning School of Materials Science and Engineering Nanchang Hangkong University Department of Chemistry National University of Singapore

The ferroelectric semiconductor material PbTiO3exhibits remarkable spontaneous polarization and photoelectric properties, positioning it as a promising polar photocatalyst. The internal electric field of ferroelectrics can separate photocarriers and enhance the catalytic performance of photocatalysts. Moreover, when combined with other semiconductors, PbTiO3contributes to the construction of a depolarization field, extending the catalytic applications of PbTiO3catalysts. PbTiO3exhibits optical absorption, semiconductor, and piezoelectric properties. Its piezoelectric polarization field enhances charge separation, modulates band structure, surface charge conduction, and heterojunction interface charge conduction,thereby amplifying photocatalytic activity. This paper begins by examining the structure, properties, and preparation methods of PbTiO3. Subsequently, it delves into the optimization of PbTiO3's structure and performance,exploring applications in photocatalysis as a ferroelectric photocatalyst. Emphasis is placed on the detailed discussion of surface modification, heterostructure formation, and ferroelectric polarization of PbTiO3ferroelectrics. These aspects are thoroughly explored for their role in regulating activity and optimizing the performance of photocatalysis and photopiezoelectric catalysis. In conclusion, the paper addresses the current research status of PbTiO3ferroelectric materials and highlights the challenges that lie *** intention is to provide valuable references for the ongoing research in PbTiO3ferroelectric materials.

关键词： Polarization

Effect of distribution of fines on evolution of cooperation in spatial public goods game

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CHINESE PHYSICS B 2024年第9期33卷 239-245页

作者： Sun, Xing-Ping Bi, Yan-Zheng Kang, Hong-wei shen, Yong Chen, Qing-Yi Yunnan Univ Sch Software Kunming 650000 Peoples R China

In the realm of public goods game, punishment, as a potent tool, stands out for fostering cooperation. While it effectively addresses the first-order free-rider problem, the associated costs can be substantial. Punishers incur expenses in imposing sanctions, while defectors face fines. Unfortunately, these monetary elements seemingly vanish into thin air, representing a loss to the system itself. However, by virtue of the redistribution of fines to cooperators and punishers, not only can we mitigate this loss, but the rewards for these cooperative individuals can be enhanced. Based upon this premise, this paper introduces a fine distribution mechanism to the traditional pool punishment model. Under identical parameter settings, by conducting a comparative experiment with the conventional punishment model, the paper aims to investigate the impact of fine distribution on the evolution of cooperation in spatial public goods game. The experimental results clearly demonstrate that, in instances where the punishment cost is prohibitively high, the cooperative strategies of the traditional pool punishment model may completely collapse. However, the model enriched with fine distribution manages to sustain a considerable number of cooperative strategies, thus highlighting its effectiveness in promoting and preserving cooperation, even in the face of substantial punishment cost.

关键词： public goods game fine distribution cooperation 02.50.Le 02.50.Ng 02.60.Cb 02.70.Uu REPLICATOR DYNAMICS PUNISHMENT REWARDS INVESTMENT ALLOCATION PROVISION SANCTIONS EMERGENCE MECHANISM

RNA m6A dynamic modification mediated by nucleuslocalized FTO is involved in follicular reserve

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Zoological Research 2024年第2期45卷 415-428页

作者： Jiao-Na Zhang Rui-Ting Wang Francesca-Gioia Klinger Shun-Feng Cheng wei shen Xiao-Feng Sun College of Life Sciences Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of ShandongQingdao Agricultural UniversityQingdaoShandong 266109China Department of Biomedicine and Prevention University of Rome Tor VergataRome 00133Italy

In eukaryotic organisms,the most common internal modification of messenger RNA(m RNA)is N6-methyladenosine(m6A).This modification can be dynamically and reversibly controlled by specific enzymes known as m6A writers and *** fat-mass and obesity-associated protein(FTO)catalyzes RNA demethylation and plays a critical role in various physiological and pathological *** research identified dynamic alterations in both m6A and FTO during the assembly of primordial follicles,with an inverse relationship observed for m6A levels and nuclear-localized FTO *** of Fto small interfering RNA(si RNA)altered the expression of genes related to cell proliferation,hormone regulation,and cell chemotaxis,and affected RNA alternative *** of the full-length Fto gene led to changes in m6A levels,alternative splicing of Cdk5,cell proliferation,cell cycle progression,and proportion of primordial ***,overexpression of Fto lacking a nuclear localization signal(NLS)did not significantly alter m6A levels or primordial follicle *** findings suggest that FTO,localized in the nucleus but not in the cytoplasm,regulates RNA m6A demethylation and plays a role in cell proliferation,cell cycle progression,and primordial follicle *** results highlight the potential of m6A and its eraser FTO as possible biomarkers and therapeutic targets.

关键词： m6A FTO Ovary Primordial follicle assembly Alternative splicing

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