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Acta Metallurgica Sinica(English Letters) 2022年第8期35卷 1291-1300页

作者： Haoyang Yu Wei Fang Jinfei Zhang Jiaxin Huang Jiaohui Yan Xin Zhang Juan Wang jianhang feng Fuxing Yin School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology Tianjin 300132China Institute of Materials and Processing Guangdong Academy of SciencesGuangzhou 510650China

The influences of minor Cu addition(2 and 4 at.%)on the microstructural evolution and room-temperature mechanical property of metastable Co_(35)Cr_(25)Fe_(30)Ni_(10)are systemically investigated in the present study.The results indicate that the thermally induced hexagonal close-packed(HCP)phase is absent when Cu was added,due to the increase in stacking fault energy(SFE).The 2%-Cu-added alloys showed the largest total elongation of 69%among the three alloys.With the addition of Cu content reaching 4 at.%,heterogeneous grain structures composed of coarse grains(~9μm)and fine grains(~4μm)and Cu-rich precipitates near the grain boundary are observed,showing the highest yield strength.Additionally,the segregation state of Cu was quantitatively characterized by electron probe microanalysis(EPMA).And effects of Cu addition on microstructures and tensile properties of(Co_(35)Cr_(25)Fe_(30)Ni_(10))_(100-x) Cu _(x) are also discussed.The findings are beneficial to comprehensively understand the Cu-containing complex concentrated alloys.

关键词： Complex concentrated alloy High entropy alloy Cu addition Microstructures Mechanical properties

Effect of titanium and rare earth microalloying on microsegregation,eutectic carbides of M2 high speed steel during ESR process

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Journal of Rare Earths 2020年第9期38卷 1030-1038,I0005页

作者： Fuxing Yin Lu Wang Zhixia Xiao jianhang feng Lin Zhao School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Research Institute for Energy Equipment Materials Hebei University of TechnologyTianjin 300130China Tianjin Key Laboratory of Materials Laminating Fabrication and Interfacial Controlling Technology Tianjin 300130China Central Iron and Steel Research Institute Beijing 100081China

The effects of RE and Ti microalloying during electroslag remelting(ESR)process on the microsegregation and morphology of eutectic M2C carbides in M2 high speed steel were investigated.The results show that the addition of 0.2 wt%RE can alleviate the segregation of C,W,Mo,V and Cr,while the morphology of eutectic M2C carbides hardly changes.The microalloying with the addition of 0.5 wt%Ti has the lowest degree of microsegregation due to the improvement of primary dendrites by the effective heterogeneous nucleating agent of(Ti,V)(C,N)particles.The addition of Ti makes the mo rphology of M2C carbides change from rod-like or maze-like shape into a coarse feathery shape,exhibiting anisotropic facet growth characteristics.For the microalloying of 0.2 wt%RE and 0.5 wt%Ti,the segregation of the main metal alloying elements is slightly more severe than that of the addition of only RE or Ti.Under the combined action of RE and Ti,the feathery eutectic M2C becomes thinner and shorter and tends to be isolated or distributed in a discontinuous network.

关键词： Microsegregation Morphology Eutectic carbides High speed steel Electroslag remelting Rare earths

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高速列车盘形制动器热-结构耦合方法研究

铁道科学与工程学报 2024年第2期21卷 456-464页

作者：刘楠金星史建航王炳锟施玉奇丰明阳中车青岛四方车辆研究所有限公司山东青岛266031 中车制动系统有限公司山东青岛266031

盘形制动器热负荷计算是高速列车制动盘研发设计的关键环节,其计算结果是列车运行参数配置的依据。开发合适的计算方法建立计算精度高、工况适用性广的热-结构耦合计算模型是盘形制动器热负荷计算的关键问题。针对动车组用轴装制动盘制... 详细信息

盘形制动器热负荷计算是高速列车制动盘研发设计的关键环节,其计算结果是列车运行参数配置的依据。开发合适的计算方法建立计算精度高、工况适用性广的热-结构耦合计算模型是盘形制动器热负荷计算的关键问题。针对动车组用轴装制动盘制动过程,充分考虑制动闸片和制动盘的几何特性、运动特性和载荷工况,提出位移梯度循环法,基于ABAQUS软件建立盘形制动器摩擦副三维瞬态传热有限元模型,运用位移梯度循环法推导出热流加载式,用以计算制动过程中产生的摩擦热流,解决摩擦作用沿制动盘周向差异造成的耦合结果偏差。运用位移梯度循环法对制动盘进行热-结构耦合分析,并将仿真结果与试验数据、现场调研成果进行对比,通过仿真与试验结果的峰值温度误差率、相关性系数等统计学指标及现场调研观测结果评定该模型的计算精度及工况适用性。研究结果表明:基于位移梯度循环法的热-结构耦合模型可有效模拟制动盘在制动过程中温度变化规律且具有良好的重复性与稳定性,结构场分析出的制动盘热裂纹失效易发位置与该型号制动盘装车运用情况相符。研究成果可有效模拟高速列车在制动时制动盘的热-结构耦合过程,尤其在大轴重下的持续制动或间隔制动工况下,制动时间越长,计算精度越高。

关键词：高速列车盘形制动器热-结构耦合热负荷计算位移梯度循环法

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人机混合智能决策范式及作战应用研究

计算机科学 2024年第6期51卷 272-281页

作者：丁炎炎冯建航叶玲郑少秋刘凡河海大学计算机与软件学院南京210098 哈尔滨工程大学水下机器人技术重点实验室哈尔滨150001 中国电子科技集团公司第二十八研究所南京210007

人机混合智能结合机器智能和人类智能,充分发挥机器和人类各自的智能优势,实现智能的跨载体和跨认知。作为一种新型智能形式,人机混合智能具有广泛的应用前景。人机混合智能决策将人的思维引入机器智能系统中,利用多智能协同完成对某种... 详细信息

人机混合智能结合机器智能和人类智能,充分发挥机器和人类各自的智能优势,实现智能的跨载体和跨认知。作为一种新型智能形式,人机混合智能具有广泛的应用前景。人机混合智能决策将人的思维引入机器智能系统中,利用多智能协同完成对某种任务或问题的混合决策。针对现有的人机混合智能决策研究缺少整体性的理论描述和分类对比,且缺少针对军事领域的作战决策系统的架构描述,从协同交互手段和决策阶段的角度对通用人机混合决策范式进行分类和比较,分析了不同范式下的人机混合智能决策系统在作战方面的应用。此外,总结了目前人机混合智能决策范式和系统存在的问题,并展望了未来的发展方向。

关键词：人机混合智能混合决策人在环内人在环上人在环外

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孕育处理和保温时间对高镍铬组织和性能影响

钢铁 2024年第1期59卷 139-147页

作者：杨宏略肖志霞冯建航陈佳崎陈兴富刘杰兵石立勇河北工业大学材料科学与工程学院天津300131 邢台德龙机械轧辊有限公司河北邢台054035

高镍铬铸铁组织中石墨和共晶碳化物的合理匹配,可使高镍铬轧离心复合轧辊具有优异的强度和硬度以及良好的抗热冲击和热裂性。然而当孕育不合理时,碳化物和石墨不仅不会得到有效改善,甚至会形成夹杂物恶化材料性能;同时,在轧辊生产过程中... 详细信息

高镍铬铸铁组织中石墨和共晶碳化物的合理匹配,可使高镍铬轧离心复合轧辊具有优异的强度和硬度以及良好的抗热冲击和热裂性。然而当孕育不合理时,碳化物和石墨不仅不会得到有效改善,甚至会形成夹杂物恶化材料性能;同时,在轧辊生产过程中,因铁水冶炼工艺和浇铸工艺的不稳定,导致冶炼后期铁水在中间包中保温时间存在不确定性。基于此,研究了高镍铬铸铁在熔炼后期分别保温3、5和7h,以及浇注前分别添加质量分数为0.4%、0.8%、1.2%的硅铁孕育剂后,铸态组织中的碳化物和石墨变化机制,比较了不同保温时间和孕育处理对铸铁材料硬度的影响规律。结果表明,随着保温时间的延长,高镍铬铸铁组织中的石墨平均尺寸与体积分数增加,但数量密度减少,共晶碳化物出现明显细化且含量减少;保温3h的样品经孕育处理后,能够有效促进石墨形核,但延长保温时间后即使提高孕育剂加入量,石墨平均尺寸和数量密度也无明显改善;保温低于5h时,孕育处理可使共晶碳化物含量减少,但延长保温时间后孕育处理使共晶碳化物含量增加。随着保温时间延长,高镍铬铸铁的硬度逐渐降低;当保温时间大于5h时,经孕育处理的样品的硬度能提高16HRC。研究表明,在高镍铬铸铁熔炼过程中,保温时间应控制在3h内,保温过长会导致石墨过度长大并降低石墨数量,此时仍可通过添加质量分数为0.4%~1.2%的孕育剂来增加石墨数量,但保温超过5h后即使添加孕育剂也无法有效提高石墨数量。

关键词：高镍铬铸铁孕育处理保温时间石墨共晶碳化物

融合多元文本信息和注意力机制的方面级情感分类方法

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计算机与数字工程 2024年第3期52卷 903-908页

作者：冯勇徐健航王嵘冰徐红艳辽宁大学信息学院沈阳110036

为了解决当前情感分类方法对于文本信息利用不充分并且缺乏对用户偏好的考虑从而导致情感分类准确率不高的问题,论文引入注意力机制来处理多元文本,并利用SRNN模型来充分地提取文本的隐藏特征,提出了一种融合多元文本信息和注意力机制... 详细信息

为了解决当前情感分类方法对于文本信息利用不充分并且缺乏对用户偏好的考虑从而导致情感分类准确率不高的问题,论文引入注意力机制来处理多元文本,并利用SRNN模型来充分地提取文本的隐藏特征,提出了一种融合多元文本信息和注意力机制的方面级情感分类方法。该方法以电商平台为研究对象,综合利用商品简介文本和用户评论文本,首先利用注意力机制使两种文本信息互相作用,得到融合了多元文本的表示向量;然后分别在正向和反向上进行处理以充分地提取文本的隐藏特征;最后对评论信息中涉及的不同方面分别以对应的方面处理模块进行训练,根据用户偏好得到其最感兴趣的方面,将特征向量输入该方面处理模块中,进行方面级情感极性计算,最终得到情感分类结果。论文在豆瓣数据集上进行了对比实验,实验结果表明,论文所提方法在准确率和F1值上相较于当前主流的基于LSTM、CNN的方法都有明显提升。

关键词：情感分类方面级多元文本注意力机制 SRNN

锂/钠-氯二次电池的最新进展——从材料构建到性能评估

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储能科学与技术 2024年第6期13卷 1824-1834页

作者：杨建航冯文婷韩俊伟魏欣茹马晨宇毛常明智林杰孔德斌青岛科技大学材料科学与工程学院山东青岛266042 中国石油大学(华东)高端化工与能源材料研究中心中国石油大学(华东)新能源学院山东青岛266580

传统锂离子电池的能量密度已难以满足日益增长的更高能量密度的需求。开发新型高能量密度二次电池是最为有效的一个策略。近期,基于商用一次锂-亚硫酰氯锂电池衍生而来的锂/钠-氯二次电池因其高能量密度而备受关注,成为替代传统锂离子... 详细信息

传统锂离子电池的能量密度已难以满足日益增长的更高能量密度的需求。开发新型高能量密度二次电池是最为有效的一个策略。近期,基于商用一次锂-亚硫酰氯锂电池衍生而来的锂/钠-氯二次电池因其高能量密度而备受关注,成为替代传统锂离子电池的有力竞争者。本文围绕锂/钠-氯二次电池的最新研究进展,综述了正极载体、负极及电解液等关键组分构建研究及其对电化学性能的影响。在正极载体方面,系统阐述了碳材料、共轭框架聚合物等载体设计对锂/钠-氯二次电池首次放电容量、可逆容量、倍率性能和温度的影响;在电解液方面,详细分析了针对反应机理、中间相产物和电解液腐蚀问题的解决策略;并简要介绍了适用于锂/钠-氯二次电池的新型合金负极。基于正极载体的理性设计与电解液系统优化,锂/钠-氯二次电池在新型二次电池领域已初现峥嵘,循环寿命可达500圈,尤其是在极端服役环境中表现优异(可在-80℃工作,电流密度最大可达16 A/g)。然而,氯物种转化动力学速率慢、活性氯物种利用率低以及氯物种对负极等的腐蚀难题仍然是限制其性能进一步提升的瓶颈,也是未来亟待解决的挑战所在。

关键词：锂/钠-氯二次电池高能量密度电极材料设计结构性能关系电化学反应动力学

维普期刊数据库博看期刊

副球菌TH21-44胞外多糖的结构表征及其抗氧化活性探究

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中国食品添加剂 2024年第6期35卷 1-7页

作者：马博文张博源黄亮周佳赵帅黄峰屈建航河南工业大学生物工程学院郑州450001

针对副球菌(Paracoccus sp.)TH21-44所产胞外多糖(exopolysaccharide,EPS),通过离子交换层析分离纯化,结合全波段扫描、电子显微镜、高效液相色谱及凝胶渗透色谱等,解析其化学组分和结构,并探究TH21-44 EPS对DPPH、ABTS+以及羟自由基清... 详细信息

针对副球菌(Paracoccus sp.)TH21-44所产胞外多糖(exopolysaccharide,EPS),通过离子交换层析分离纯化,结合全波段扫描、电子显微镜、高效液相色谱及凝胶渗透色谱等,解析其化学组分和结构,并探究TH21-44 EPS对DPPH、ABTS+以及羟自由基清除能力和还原能力,评估TH21-44 EPS的抗氧化活性。结果表明,副球菌TH21-44的EPS由两种多糖组分构成,其中EPS-1为主成分,其总糖占比92.63%,并含有少量蛋白和硫酸盐,表观结构呈现粗糙且致密多孔的片状或树杈状,单糖组成以葡萄糖、半乳糖和甘露糖为主;抗氧化结果表明,EPS-1在5 mg/mL浓度时,对DPPH和羟自由基的清除力分别为59.61%和78.55%,EPS-1为3 mg/mL浓度时对ABTS清除力达99.36%,与Vc持平。本研究结果可为微生物胞外多糖的菌种资源开发和应用提供参考。

关键词：副球菌胞外多糖结构表征抗氧化

Engineering plants to secrete affinity-tagged pathogen elicitors for deciphering immune receptor complex or inducing enhanced immunity

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Journal of Integrative Plant Biology 2020年第6期62卷 761-776页

作者： Shuang Miao Jiuer Liu jianhang Guo Jian-feng Li Guangdong Provincial Key Laboratory of Plant Resources State Key Laboratory of BiocontrolMOE Key Laboratory of Gene Function and RegulationSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

Plant cells mount plenty of pattern-recognition receptors(PRRs)to detect the microbe-associated molecular patterns(MAMPs)from potential microbial pathogens.MAMPs are overrepresented by proteinaneous patterns,such as the flg22 peptide from bacterial flagellin.Identification of PRR receptor complex components by forward or reverse genetics can be time/labor-consuming,and be confounded by functional redundancies.Here,we present a strategy for identifying PRR complex components by engineering plants to inducibly secrete affinity-tagged proteinaneous MAMPs to the apoplast.The PRR protein complexes bound to self-secreted MAMPs are enriched through affinity purification and dissected by mass spectrometry.As a proof of principle,we could capture the flg22 receptor FLS2 and co-receptor BAK1 using Arabidopsis plants secreting FLAG-tagged flg22 under estradiolinduction.Moreover,we identified receptor-like kinases LIK1 and PEPR1/PEPR2 as potential components in the FLS2 receptor complex,which were further validated by protein–protein interaction assays and the reverse genetics approach.Our study showcases a simple way to biochemically identify endogenous PRR complex components without overexpressing the PRR or using chemical crosslinkers,and suggests a possible crosstalk between different immune receptors in plants.A modest dose of estradiol can also be applied to inducing enhanced immunity in engineered plants to both bacterial and fungal pathogens.

关键词： immunity complex mount

Human 8-cell embryos enable efficient induction of disease-preventive mutations without off-target effect by cytosine base editor

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Protein & Cell 2023年第6期14卷 416-432页

作者： Yinghui Wei Meiling Zhang Jing Hu Yingsi Zhou Mingxing Xue jianhang Yin Yuanhua Liu Hu feng Ling Zhou Zhifang Li Dongshuang Wang Zhiguo Zhang Yin Zhou Hongbin Liu Ning Yao Erwei Zuo Jiazhi Hu Yanzhi Du Wen Li Chunlong Xu Hui Yang Center for Reproductive Medicine International Peace Maternity and Child Health HospitalInnovative Research Team of High-level Local Universities in ShanghaiSchool of MedicineShanghai Jiao Tong UniversityShanghai 2000301.Center for Reproductive MedicineInternational Peace Maternity and Child Health HospitalInnovative Research Team of High-level Local Universities in ShanghaiSchool of MedicineShanghai Jiao Tong UniversityShanghai 200030China Institute of Neuroscience State Key Laboratory of NeuroscienceKey Laboratory of Primate NeurobiologyCAS Center for Excellence in Brain Science and Intelligence TechnologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China Lingang Laboratory Shanghai Research Center for Brain Science and Brain-Inspired Intelligence TechnologyShanghai 200031China Center for Reproductive Medicine Ren Ji HospitalSchool of MedicineShanghai Key Laboratory for Assisted Reproduction and Reproductive GeneticsShanghai Jiao Tong UniversityShanghai 200127China The MOE Key Laboratory of Cell Proliferation and Differentiation School of Life SciencesGenome Editing Research CenterPeking UniversityBeijing 100871China Center for Reproductive Medicine Shandong UniversityJinan 250012China Center for Reproductive Medicine Anhui Provincial Maternal and Child Health HospitalHefei 230001China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518000China Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefei 230022China

Approximately 140 million people worldwide are homozygous carriers of APOE4(ε4),a strong genetic risk factor for late onset familial and sporadic Alzheimer’s disease(AD),91%of whom will develop AD at earlier age than heterozygous carriers and noncarriers.Susceptibility to AD could be reduced by targeted editing of APOE4,but a technical basis for controlling the off-target effects of base editors is necessary to develop low-risk personalized gene therapies.Here,we first screened eight cytosine base editor variants at four injection stages(from 1-to 8-cell stage),and found that FNLS-YE1 variant in 8-cell embryos achieved the comparable base conversion rate(up to 100%)with the lowest bystander effects.In particular,80%of AD-susceptibleε4 allele copies were converted to the AD-neutralε3 allele in humanε4-carrying embryos.Stringent control measures combined with targeted deep sequencing,whole genome sequencing,and RNA sequencing showed no DNA or RNA off-target events in FNLS-YE1-treated human embryos or their derived stem cells.Furthermore,base editing with FNLS-YE1 showed no effects on embryo development to the blastocyst stage.Finally,we also demonstrated FNLS-YE1 could introduce known protective variants in human embryos to potentially reduce human susceptivity to systemic lupus erythematosus and familial hypercholesterolemia.Our study therefore suggests that base editing with FNLS-YE1 can efficiently and safely introduce known preventive variants in 8-cell human embryos,a potential approach for reducing human susceptibility to AD or other genetic diseases.

关键词： human embryo APOE4 disease-preventive mutations base editor