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Strategy of preparing smCo based films with high coercivity and remanence ratio achieved by temperature and chemical optimization

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Journal of Rare Earths 2024年第7期42卷 1289-1297,I0004页

作者： Yansong Gong Zhaoguo Qiu Sizhe Liang Xinrui Zheng Hongxia Meng Zhigang Zheng Deyang Chen Shengfu Yuan Weixing Xia Dechang zeng J.P.Liu School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Zhongshan R&D Center for Materials Surface and Thin Films Technology of the South China University of Technology Gent Materials Surface Technology(Guangdong)Co.Ltd.Zhongshan528437China Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou510006China Yangjiang Branch Guangdong Laboratory Materials Science and Technology Yangjiang Advanced Alloys LaboratoryYangjiang529500China Laboratory of Rare-Earth Magnetic Functional Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China Department of Physics University of Texas at ArlingtonArlingtonTX76019USA

smCo based films with excellent intrinsic magnetic properties have promising applications in micro-electro-mechanical system(MEMS).However,due to the complexity of phase composition and uncontrollable crystallization degree of smCo hard magnetic phase in the film,both the coercivity(Hc)and remanence(Mr)of films are difficult to enhance *** this paper,smCo based films were deposited with a Cr underlayer and capping layer on single crystal Si substrates via magnetron sputtering *** effects of annealing parameters and sm/Co atomic ratio on the phase structure and coercivity of films are *** adjusting the sm/Co atomic ratio from 1:5 to 1:4,Co soft magnetic phase disappears and the single phase smCo5 is obtained,leading to the increase of coercivity of the films from 30 to 34 *** influence of deposition temperature and Cu doping on magnetic properties of smCo based films was *** the deposition temperature increases from room temperature to 250℃,the coercivity will further increase from 34 to 51 ***,a severe kink is observed in the demagnetization curves due to the poor exchanged *** analysis of transmission electron microscopy(TEM)confirms that the average size of non-hard magnetic amorphous phase exceeds the effective exchanged coupling length of smCo5,which contributes to the decoupling and low remanence ***,doping Cu and applying a post-annealing process can significantly improve the crystallization degree of the *** the coercivity and the remanence ratio of the demagnetization curves are greatly *** propose a plausible strategy to prepare the smCo based films with high coercivity and remanence ratio by temperature and chemical optimization,which can be utilized in high performed MEMS devices.

关键词： Rare earths smCo based films Phase composition Crystallization conditions Coercivity Remanence ratio

吸气式高超声速飞行器突防效能及影响因素分析

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空天技术 2024年第1期2024卷 78-84页

作者：李探奇曾宏刚刘小明中国航空研究院北京航空航天大学

针对吸气式高超声速飞行器能否有效突破蓝方防空拦截阵地，实现对蓝方要地进行打击的问题，分析了突防速度、机动过载等性能指标对吸气式高超声速飞行器突防效能的影响，为吸气式高速飞行器的设计指标论证提供了参考。以高超声速飞行器... 详细信息

针对吸气式高超声速飞行器能否有效突破蓝方防空拦截阵地，实现对蓝方要地进行打击的问题，分析了突防速度、机动过载等性能指标对吸气式高超声速飞行器突防效能的影响，为吸气式高速飞行器的设计指标论证提供了参考。以高超声速飞行器突防搭载标准-6防空导弹的驱逐舰阵地为典型研究场景，建立了基于FlightSim平台的标准-6导弹动力学与制导模型，完成了不同相对位置关系下拦截高超声速飞行器的脱靶量计算，得到了防空导弹对高超声速飞行器的杀伤区范围。对比分析了高超声速飞行器的突防速度、机动过载等指标变化对防空导弹杀伤区的影响，发现高超声速突防可以有效提高杀伤区近界并压缩杀伤区侧界，增加防御方拦截难度与成本，验证了高超声速突防的军事价值。

关键词：突防速度机动过载指标论证制导模型杀伤区高速突防

Magnetic and electrical transport properties in GdAlSi and smAlGe

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Chinese Physics B 2024年第7期33卷 554-560页

作者：巩静王欢马小平曾祥雨林浚发韩坤王乙婷夏天龙 Department of Physics Renmin University of ChinaBeijing 100872China Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Laboratory for Neutron Scattering Renmin University of ChinaBeijing 100872China

We conduct a detailed examination of the magnetic and electrical transport properties in GdAlSi and smAlGe crystals,which possess a LaPtSi-type structure(space group I4_(1)md).The magnetic susceptibility data unambiguously reveal magnetic ordering below a characteristic transition temperature(T_(N)).For GdAlSi,a hysteresis loop is observed in the magnetization and magnetoresistance curves within the ab plane when the magnetic field is applied below T_(N),which is around32 *** specific heat anomalies are detected at 32 K for GdAlSi and 6 K for smAlGe,confirming the occurrence of magnetic *** addition,the extracted magnetic entropy at high temperatures is consistent with the theoretical value of Rln(2J+1) for J=7/2 in Gd^(3+) and J=5/2 in sm^(3+),*** also exhibits Schottky-like specific heat ***,both GdAlSi and smAlGe exhibit positive magnetoresistance and a normal Hall effect.

关键词： crystal growth magnetism magnetotransport properties specific heat

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高地震烈度区复杂地质条件渡槽结构

清华大学学报（自然科学版） 2024年第7期64卷 1264-1277页

作者：张延杰曾显志王海深韩钟骐邓开来潘鹏云南省滇中引水工程有限公司昆明650000 清华大学土木工程系北京100084 西南交通大学土木工程学院成都610031

滇中引水工程规模巨大,面临高地震烈度、多活动断裂、复杂地质条件等众多工程建设难题。渡槽是滇中引水工程中用于跨越河流和山谷等特殊地形的重要输水结构之一,确保渡槽结构安全是保障输水功能持续的关键和前提。针对滇中引水工程渡槽... 详细信息

滇中引水工程规模巨大,面临高地震烈度、多活动断裂、复杂地质条件等众多工程建设难题。渡槽是滇中引水工程中用于跨越河流和山谷等特殊地形的重要输水结构之一,确保渡槽结构安全是保障输水功能持续的关键和前提。针对滇中引水工程渡槽结构,部分学者已开展大量理论分析、模型试验及数值模拟等研究工作,该文归纳分析了相关研究成果,并展望未来的研究趋势,旨在为类似工程的建设和发展提供参考和借鉴。研究表明:水槽相互作用及土结相互作用模拟是准确分析渡槽结构地震响应的关键,形成考虑土体渡槽水体的多物理场耦合分析技术,可为滇中引水工程渡槽结构的数值分析提供技术支撑。在此基础上,研究高地震烈度区、复杂地质条件下渡槽结构的抗震及减隔震性能,分析V形河谷等地形差异对渡槽结构的抗震性能影响机理,阐明不同减隔震措施的减隔震机理。随着社会不断发展,人们对渡槽结构在输水能力和跨越能力方面的需求日益增加,如何进一步保证在高地震烈度区和复杂地质条件下的渡槽结构安全和输水功能持续意义重大。利用槽内水体晃动实现调谐液体阻尼器减震效果、研发新型减隔震装置和渡槽防渗止水是未来重要的发展方向。

关键词：滇中引水渡槽高地震烈度复杂地质地震响应

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基于卷积自编码器的侧信道分析

计算机与现代化 2024年第3期 110-114,121页

作者：曾钟静昕甘刚成都信息工程大学网络空间安全学院四川成都610225

兴趣点作为侧信道分析中的重要指标,准确选择出有效的兴趣点具有重要意义。针对公钥密码算法的聚类模型中兴趣点选择效果不佳,导致低识别率的问题,本文提出一种基于卷积自编码器的兴趣点选择方法。该方法在数据预处理后使用卷积自编码... 详细信息

兴趣点作为侧信道分析中的重要指标,准确选择出有效的兴趣点具有重要意义。针对公钥密码算法的聚类模型中兴趣点选择效果不佳,导致低识别率的问题,本文提出一种基于卷积自编码器的兴趣点选择方法。该方法在数据预处理后使用卷积自编码器来对数据特征进行学习,将其编码输出作为选择的兴趣点,结合聚类算法来完成侧信道攻击,最终成功恢复出密钥。实验以sm2解密算法中的多倍点运算过程作为研究对象,结果显示本文提出的方法可以用于侧信道分析中数据的兴趣点选择,大大提高了神经网络在侧信道分析方面的灵活性和实用性。

关键词：侧信道卷积自编码器聚类 sm2算法兴趣点选择

Study on structure and magnetic entropy changes of Ce_(2-x)Pr_xFe_(16.5)Co_(0.5) alloys

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Rare Metals 2006年第z1期25卷 626-629页

作者： ZHONG Xichun zeng Dechang LUO Zhijian School of Mechanical Engineering South China University of TechnologyGuangzhou 510640 China School of Mechanical Engineering South China University of TechnologyGuangzhou 510640 China School of Mechanical Engineering South China University of TechnologyGuangzhou 510640 China

A series of Ce2-xPrxFe16.5Co0.5 alloys were prepared by arc melting under purified argon atmosphere. The structure and magnetic entropy changes in Ce2-xPrxFe16.5Co0.5 alloys were investigated by means of X-ray diffraction pattern and MPMS XL-7 magnetometer. The experimental results show that the crystal structure of Ce2-xPrxFe16.5Co0.5 alloys keeps in Th2Zn17-type rhombohedral, and the Curie temperature of Ce2-xPrxFe16.5Co0.5 alloys can be shifted to room temperature around by a composition adjustment. The magnetic entropy changes (-Δsm) in Ce2-xPrxFe16.5Co0.5 alloys are relatively large, and a platform of magnetic entropy changes appears near the temperature TC. Ce2-xPrxFe16.5Co0.5 alloys are the potential working media for magnetic refrigeration with their stable chemical properties and especially low price.

关键词： Ce2-xPrxFe16.5Co0.5 alloys magnetic entropy change magnetic refrigeration

高职跨境电商双创人才专创融合课程体系探究——以广东交通职业技术学院为例

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广东交通职业技术学院学报 2024年第2期23卷 111-115页

作者：黄琦琪曾艳英广东交通职业技术学院广东广州510650

作为外贸新业态,跨境电商产业链亟需创新复合型技术技能人才。人才链新变化迫使教育链深化改革契合产业链新需求。专创融合是双创人才培养的有力途径,高职院校应以课程体系构建为着力点,重构跨境电商双创人才专创融合课程体系。本文以... 详细信息

作为外贸新业态,跨境电商产业链亟需创新复合型技术技能人才。人才链新变化迫使教育链深化改革契合产业链新需求。专创融合是双创人才培养的有力途径,高职院校应以课程体系构建为着力点,重构跨境电商双创人才专创融合课程体系。本文以广东交通职业技术学院为例,在分析高职双创教育现状基础上,总结了重构纵横交错的课程体系、搭建校内校外的实践平台、组建三阶递进双创导师团队的广交探索经验,以期为高职院校跨境电商双创人才培养提供有益借鉴。

关键词：跨境电商创新创业专创融合课程体系

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两份海南地方木豆资源的核型分析

草业科学 2024年第7期41卷 1645-1649页

作者：程志号孙长君郭素霞曾学蔚严琳玲吴琼中国热带农业科学院热带生物技术研究所/海南省香蕉遗传改良重点实验室海南海口571101 中国热带农业科学院热带作物品种资源研究所海南海口571101

木豆(Cajanus cajan)是我国热带亚热带地区重要的豆类作物,是一种集粮、饲料、药物为一体的多用途植物,同时,作为先锋植物,在水土保持、土壤改良等方面有重要功能。海南木豆种植时间长、资源多样性高,但细胞遗传学方面的报道目前较少。... 详细信息

木豆(Cajanus cajan)是我国热带亚热带地区重要的豆类作物,是一种集粮、饲料、药物为一体的多用途植物,同时,作为先锋植物,在水土保持、土壤改良等方面有重要功能。海南木豆种植时间长、资源多样性高,但细胞遗传学方面的报道目前较少。本研究以海南两个重要木豆产区‘保亭’和‘白沙’木豆地方资源为材料,通过核型分析发现,‘保亭’木豆核型公式为2n=2x=22=16m+6sm,其中10号染色体有一对随体,相对长度组成为2n=1L+5M2+3M1+2s,为1A型;‘白沙’木豆核型公式为2n=2x=22=20m+2sm,未发现随体,相对长度组成为2n=1L+4M2+5M1+1s,为2A型。本研究结果为木豆资源鉴定提供了新技术,也为种质创新和新品种选育提供参考。

关键词：木豆资源核型分析随体对称性

Task Coordination Organization Model and the Task Allocation Algorithm for Resource Contention of the Syncretic System

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Tsinghua Science and Technology 2016年第4期21卷 459-470页

作者： Danfeng Wu Guangping zeng Di He Zhaopeng Qian Qingchuan Zhang School of Computer&Communication Engineering University of Science&Technology BeijingBeijing 100083China School of Software Liaoning Technical UniversityHuludao 125105China Beijing Key Laboratory of Knowledge Engineering for Materials Science Beijing 100083China Graduate Center City University of New YorkNew YorkNY 10016USA

At present, robot embedded systems have some common problems such as closure and poor dynamic evolution. Aiming at resolving this situation, our paper focuses on improvements to the robot embedded system and sets up a new robot system architecture, and we propose a syncretic mechanism of a robot and SoftMan （sm）. In the syncretic system, the structural organization of the SoftMan group and its modes are particularly important in establishing the task coordination mechanism. This paper, therefore, proposes a coordination organization model based on the SoftMan group, and studies in detail the process of task allocation for resource contention, which facilitates a rational allocation of system resources. During our research, we introduced Resource Requirement Length Algorithm （RRLA） to calculate the resource requirements of the task and a resource conformity degree allocation algorithm of Resource Conformity Degree Algorithm （RCDA） for resource contention. Finally, a comparative evaluation of RCDA with five other frequently used task allocation algorithms shows that RCDA has higher success and accuracy rates with good stability and reliability.

关键词： SoftMan robot syncretic system organization model task allocation game theory