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EuBa_(2)Cu_(3)O_(7-δ)超导带材中掺杂相对He^(+)离子辐照缺陷演化及超导电性的影响

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物理学报 2024年第8期73卷 305-316页

作者：赵珀王建强陈梅清杨金学苏钲雄卢晨阳刘华军洪智勇高瑞西安交通大学核科学与技术学院西安710049 中国科学院等离子体物理研究所合肥230031 合肥国际应用超导中心合肥230071 上海超导科技股份有限公司上海201203

为探究稀土钡铜氧化物(REBCO)第二代高温超导带材中掺杂相对离子辐照缺陷演化及超导电性的影响机理,本文采用能量为1.4 MeV的He^(+)离子对国产化未掺杂和掺杂摩尔分数3.5%BaHfO_(3)(BHO)的EuBa_(2)Cu_(3)O_(7-δ)带材进行三种不同剂量... 详细信息

为探究稀土钡铜氧化物(REBCO)第二代高温超导带材中掺杂相对离子辐照缺陷演化及超导电性的影响机理,本文采用能量为1.4 MeV的He^(+)离子对国产化未掺杂和掺杂摩尔分数3.5%BaHfO_(3)(BHO)的EuBa_(2)Cu_(3)O_(7-δ)带材进行三种不同剂量的室温辐照实验并退火.电学性能测试表明,随着辐照剂量的增加,掺杂带材的临界电流密度仍均高于未掺杂带材并且下降程度更小.透射电镜表征结果证明,超导层中通过掺杂BHO纳米相引入局域应变改变了辐照He缺陷的迁移行为,在一定范围内修复了损伤的超导结构,提高了带材载流能力的辐照耐受性.同时BHO纳米柱作为强钉扎中心使得掺杂带材临界电流密度的磁场依赖性和温度依赖性受辐照影响更小.不同于中子或重离子辐照后,通过退火可以恢复材料一定程度的超导电性,本文中大剂量He^(+)离子辐照的两种带材经氧气氛退火后,其电学性能继续恶化.相比于未掺杂带材,掺杂带材中BHO产生的局域应变在高温下抑制了辐照He缺陷在三维方向上的尺寸增长,改变了磁通钉扎特性,延缓了因氦泡长大而造成的超导层结构无序和非晶化.本研究为评估REBCO超导带材在辐照环境下的工况服役行为提供了参考依据.

关键词： REBCO超导带材辐照损伤临界电流密度微观结构表征

Study on the mechanism and reaction characteristics of metal-supported phosphogypsum as oxygen carrier in a chemical looping gasification application

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Journal of Environmental Sciences 2024年第4期138卷 428-438页

作者： Jing yang Yujie Ren Shuoyu chen Jinsuo lu School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

This study aimed to explore the chemical looping gasification(CLG)reaction characteristics of the metal-supported composite phosphogypsum(PG)oxygen carriers(OCs)and the thermodynamic *** FactSage 7.1 thermodynamic simulation was used to explore the oxygen release and H_(2)S removal *** experimental results showed that the syngas yield of CLG with PG-CuFe_(2)O_(4)was more than that with PG-Fe_(2)O_(3)20/CuO40 or PG-Fe_(2)O_(3)30/CuO30 OC at 1023 K when the water vapor content was ***,the maximum syngas yield of the CO selectivity was 70.3% and of the CO_(2)selectivity was 23.8%.The H_(2)/CO value was 0.78,and the highest carbon conversion efficiency was 91.9% in PG-CuFe_(2)O_(4)at the gasification temperature of 1073 *** metal-supported PG composite oxygen carrier was proved not only as an oxygen carrier to participate in the preparation of syngas but also as a catalyst to catalyze coal gasification ***,both the experimental results and FactSage 7.1 thermodynamic analysis revealed that the trapping mechanism of H_(2)S by composite OCs was as follows:CuO first lost lattice oxygen as an oxygen carrier to generate Cu_(2)O,which,in turn,reacted with H_(2)S to generate Cu_(2)*** study provided efficient guidance and reference for OC design in CLG.

关键词： Metal-supported composite phosphogypsum Reaction characteristics Thermodynamic mechanism Chemical looping gasification

Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions

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Nuclear Science and Techniques 2024年第1期35卷 134-144页

作者： Yi-Ping Xu Si-lu chen Dan-yang Pang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China School of Physics Beihang UniversityBeijing 100191China

The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave *** target nuclei included both stable and unstable nuclei,and the incident energies reached 200 *** results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 ***,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive *** average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 ***,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.

关键词： Microscopic optical model potential (p,d)transfer Spectroscopic factors

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一种可降低结构性变化的本体演化算法

计算机技术与发展 2024年第6期34卷 45-52页

作者：陆晨阳袁嵩高峰顾进广武汉科技大学计算机科学与技术学院湖北武汉430065 湖北省智能信息处理与实时工业系统重点实验室湖北武汉430065 中冶南方连铸技术工程有限责任公司湖北武汉430223

在Web语义环境中,如何降低本体在不断演化的过程中的结构性变化是一项具有挑战性的任务。针对这一问题,提出了一种本体演化算法,旨在降低本体演化过程中的结构性变化,从而提高本体的稳定性和可维护性。与传统的本体演化方法主要关注实... 详细信息

在Web语义环境中,如何降低本体在不断演化的过程中的结构性变化是一项具有挑战性的任务。针对这一问题,提出了一种本体演化算法,旨在降低本体演化过程中的结构性变化,从而提高本体的稳定性和可维护性。与传统的本体演化方法主要关注实体间关系不同,该文在计算本体演化代价时在实体频率和实体间关系频率的基础上综合考虑了实体之间的概念关系,从而实现了对实体影响的更细粒度分析。此外,还提出新的附加演化策略,以便在演化过程中选取最优的演化策略,保留更多复杂的语义关系以实现最小结构性变化。实验结果表明,提出的演化方法在处理涉及复杂语义关系的本体演化时表现出色,有效地降低了演化代价并提高了本体演化前后的结构相似度。这些研究成果在Web语义环境中对本体进行演化和更新方面具有重要意义,为本体工程领域提供了有益的改进方向和实践经验。

关键词：本体本体演化语义关系演化策略结构性变化

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Synthesis of uniform two-dimensional MoS_(2) films via thermal evaporation

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Nano Research 2024年第4期17卷 3217-3223页

作者： Xue-Wei lu Zhewei Li chen-Kai yang Weijia Mou Liying Jiao Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

Two-dimensional(2D)molybdenum disulfide(MoS_(2))holds great potential for various applications such as electronic devices,catalysis,lubrication,anti-corrosion and so *** evaporation is a versatile thin film deposition technique,however,the conventional thermal evaporation techniques face challenges in producing uniform thin films of MoS_(2) due to its high melting temperature of 1375℃.As a result,only thick and rough MoS_(2) films can be obtained using these *** address this issue,we have designed a vacuum thermal evaporation system specifically for large-scale preparation of MoS_(2) thin *** using K2MoS4 as the precursor,we achieved reliable deposition of uniform polycrystalline MoS_(2) thin films with a size of 50 mm×50 mm and controllable thickness ranging from 0.8 to 2.4 *** approach also allows for patterned deposition of MoS_(2) using shadow masks and sequential deposition of MoS_(2) and tungsten disulfide(WS_(2)),similar to conventional thermal evaporation ***,we have demonstrated the potential applications of the obtained MoS_(2) thin films in field effect transistors(FETs),memristors and electrocatalysts for hydrogen evolution reaction(HER).

关键词： thermal evaporation molybdenum disulfide two-dimensional memristors hydrogen evolution reaction

Oils with different degree of saturation:effects on ileal digestibility of fat and corresponding additivity and bacterial community in growing pigs

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1657-1668页

作者： lu Wang Yifan chen Yuansen yang Nuo Xiao Changhua Lai State Key Laboratory of Animal Nutrition Ministry of Agriculture and Rural Affairs Feed Industry CentreChina Agricultural UniversityNo.2 Yuanmingyuan West RoadHaidian DistrictBeijing 100193China College of Animal Science and Technology Hebei Agricultural UniversityHebei 071000China

Background Oils are important sources of energy in pig *** combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of oil *** experiment was conducted to evaluate the effects of oils with different degree of saturation on the fat digestibility and corresponding additivity and bacterial community in growing *** Eighteen crossbred(Duroc×Landrace×Yorkshire)barrows(initial body weight:29.3±2.8 kg)were surgically fitted with a T-cannula in the distal *** experimental diets included a fat-free basal diet and 5 oil-added *** 5 oil-added diets were formulated by adding 6%oil with different ratio of unsaturated to saturated fatty acids(U:S)to the basal *** 5 oils were palm oil(U:S=1.2),canola oil(U:S=12.0),and palm oil and canola oil were mixed in different proportions to prepare a combination of U:S of 2.5,3.5 and 4.5,*** The apparent and standardized ileal digestibility(AID and SID)of fat and fatty acids increased linearly(Plues(P<0.05).The abundance of Romboutsia and Turicibacter in pigs fed diet containing palm oil was greater than that in rapeseed oil treatment group,and the two bacteria were negatively correlated with SID of C16:0,C18:0 and SFA(P<0.05).

关键词： Additivity Bacterial community Fat and fatty acids Growing pigs Ratio of unsaturated to saturated fatty acids Standardized ileal digestibility

Assessing the energy release characteristics during the middle detonation reaction stage of aluminized explosives

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Defence Technology（防务技术） 2024年第3期33卷 270-277页

作者： Kun yang Lang chen Danyang Liu Bin Zhang Jianying lu Junying Wu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows significant ***,at present,there are few effective methods for evaluating the energy release characteristics of the middle reaction stage of such explosives,which can have a duration of tens to hundreds of *** present work demonstrates an approach to assessing the midstage of an aluminized explosive detonation based on a water push test employing a high degree of *** this method,the explosive is contained in a steel cylinder having one end closed that is installed at the bottom of a transparent water *** detonation,the gaseous products expand in one direction while forcing water ahead of *** resulting underwater shock wave and the interface between the gas phase products and the water are tracked using an ultra-high-speed framing and streak *** shock wave velocity in water and the expansion work performed by the gaseous detonation products were calculated to assess the energy release characteristics of aluminized explosives such as CL-20 and RDX in the middle stage of the detonation *** the middle stage of the detonation process of these aluminized explosives,the aluminum reaction reduced the attenuation of shock waves and increased the work performed by gas phase products.A higher aluminum content increased the energy output while the presence of oxidants slowed the energy release *** work demonstrates an effective means of evaluating the performance of aluminized explosives.

关键词： Aluminized explosive Non-ideal detonation Water push test Energy release

Frustrated superconductivity and sextetting order

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 168-176页

作者： Zhiming Pan chen lu Fan yang Congjun Wu Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China New Cornerstone Science Laboratory Department of PhysicsSchool of ScienceWestlake UniversityHangzhou 310024China School of Physics Beijing Institute of TechnologyBeijing 100081China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

The superconducting state typically favors a uniform spatial distribution akin to ***,the pair-densitywave state exhibits sign changes in the pairing order,leading to potential frustrations in phase *** propose a mechanism to the sextetting order stemming from the frustrations in the phase coherence of a pair-density-wave state,whose spatial modulation manifests a vortex-antivortex honeycomb *** classical ground state configurations are mapped to Baxter's three-coloring model,revealing a macroscopic degeneracy accompanied by extensive *** phase coherence problem intertwines the U(1)phases and the vorticity *** the resultant color and phase fluctuations suppress the pair-densitywave order,they maintain the sextetting order above the superconducting transition temperature(T_(c)).The 1/3-fractional vortex emerges as the fundamental topological defect in the sextetting *** novel mechanism of frustrated superconductivity provides an alternative explanation for the experimental observed fractional oscillations in CsV_(3)Sb_(5).

关键词： frustrated superconductivity pair density wave charge-6e order

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Vehicle Abnormal Behavior Detection Based on Dense Block and Soft Thresholding

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Computers, Materials & Continua 2024年第6期79卷 5051-5066页

作者： Yuanyao lu Wei chen Zhanhe Yu Jingxuan Wang Chaochao yang School of Information Science and Technology North China University of TechnologyBeijing100144China School of Electrical and Control Engineering North China University of TechnologyBeijing100144China

With the rapid advancement of social economies,intelligent transportation systems are gaining increasing *** to these systems is the detection of abnormal vehicle behavior,which remains a critical challenge due to the complexity of urban roadways and the variability of external *** research on detecting abnormal traffic behaviors is still nascent,with significant room for improvement in recognition *** address this,this research has developed a new model for recognizing abnormal traffic *** model employs the R3D network as its core architecture,incorporating a dense block to facilitate feature *** approach not only enhances performance with fewer parameters and reduced computational demands but also allows for the acquisition of new features while simplifying the overall network ***,this research integrates a self-attentive method that dynamically adjusts to the prevailing traffic conditions,optimizing the relevance of features for the task at *** temporal analysis,a Bi-LSTM layer is utilized to extract and learn from time-based data *** research conducted a series of comparative experiments using the UCF-Crime dataset,achieving a notable accuracy of 89.30%on our test *** results demonstrate that our model not only operates with fewer parameters but also achieves superior recognition accuracy compared to previous models.

关键词： Vehicle abnormal behavior deep learning ResNet dense block soft thresholding