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Zirconium nitride as a highly efficient nitrogen source to synthesize the metal nitride clusterfullerenes

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Science China Chemistry 2021年第1期64卷 29-33页

作者： yuxi lu Jie Zhang Chong Zhao Mingzhe Nie Chunru Wang Taishan Wang Beijing National Laboratory for Molecular Sciences Key Laboratory of Molecular Nanostructure and NanotecnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Metal nitride clusterfullerenes(NCFs)have significant applications in molecular electronics,biomedical imaging,and nonlinear optical devices due to their unique ***,their wide applications are limited by the production *** this work,the yields of metal nitride clusterfullerenes M3N@C80(M=Y,Sc,Gd)were greatly enhanced by utilizing zirconium nitride(Zr N)as an efficient nitrogen source for the arc-discharge *** with the traditional synthetic route using N2gas as nitrogen source,the Zr N inside graphite tube can be vaporized simultaneously with metal and graphite,and then afford the high concentration of nitrogen atoms in the arc region,which will promote the formation of metal nitride clusterfullerenes *** Zr N can promote the yields of Y3N@C80,Sc3N@C80and Gd3N@C80,revealing the universal applicability of Zr N as a highly efficient nitrogen ***,the yield of Sc3N@C80was greatly improved when adding Zr N,and it shows over double yield compared to traditional synthetic route using *** addition,Zr N can also enhance the yields of paramagnetic azametallofullerene M2@C79N due to the high concentration of nitrogen atoms in the arc *** new method enhances the production quantity of metal nitride clusterfullerenes and azametallofullerenes,and it will greatly promote the research and application of these molecular carbon materials.

关键词： metal nitride clusterfullerenes zirconium nitride nitrogen source high yield arc-discharge method

Synergistic modulation of spin and fluorescence signals in a nano-Saturn assembled by a metallofullerene and cycloparaphenylene nanohoop

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Nano Research 2023年第2期16卷 3372-3378页

作者： Jie Zhang Zhenlin Qiu Chong Zhao yuxi lu Wang Li Linshan Liu Chunru Wang Yuanzhi Tan Taishan Wang Beijing National Laboratory for Molecular Sciences Key Laboratory of Molecular Nanostructure and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China University of Chinese Academy of Sciences Beijing 100049China School of Pharmacy Guizhou Medical UniversityGuiyang 550025China

Spin-based interdisciplinary research has attracted considerable attention,and various applications in magnetic memory,quantum science,and precision measuring technology have been *** this study,we induced a fluorescence property in a spin-active molecule by supramolecular assembly and realized a synergistic modulation of its spin and fluorescence properties.A Saturn-shaped supramolecular complex was synthesized using a spin-active metallofullerene Sc_(3)C_(2)@C80 with a fluorescent nanohoop of tetra-benzothiadiazole-based[12]cycloparaphenylene(TB[12]CPP),and its spin and fluorescence properties were comprehensively ***-dependent electron paramagnetic resonance(EPR)spectroscopy and fluorescence analyses were *** changes in the EPR signals and fluorescence peaks were discovered in the temperature range of 170–290 *** on nuclear magnetic resonance observations and theoretical calculations,a temperature-dependent host–guest interaction between Sc_(3)C_(2)@C_(80)and a nanohoop was demonstrated,which explained the synchronous changes in the EPR signals and fluorescence peaks for Sc_(3)C_(2)@C_(80)⊂TB[12]*** application of Sc_(3)C_(2)@C_(80)as a molecular spin system to probe the host–guest interaction was also *** results show that the supramolecular assembly can be used to design advanced spin systems coupled with optical and magnetic behaviors based on paramagnetic and luminescent molecules.

关键词： metallofullerene nanohoop electron spin fluorescence host–guest interaction

A molecular brake hoop for the motion of metal atoms inside fullerene cage

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Science China Chemistry 2022年第8期65卷 1601-1606页

作者： yuxi lu Chong Zhao Jie Zhang Wang Li Jiayi Liang Linshan Liu Yongguang Li Chunru Wang Taishan Wang Beijing National Laboratory for Molecular Sciences Key Laboratory of Molecular Nanostructure and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Pharmacy Guizhou Medical UniversityGuian New District 550025China College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 311121China

Molecular machines have attracted extensive attention due to their fancy concept and their potential to influence the science and *** dynamic motion of encapsulated metallic clusters is a distinctive character for endohedral *** the development of molecular rotors based on metallofullerenes,the most challenging issue is how to control the motion of untouchable metallic cluster inside fullerene *** this work,we report a molecular brake hoop for the motion of metal atoms inside fullerene cage.A cycloparaphenylene of[12]CPP was employed to hoop the metallofullerene and produce two supramolecular complexes of Sc_(3)N@C_(80)⊂[12]CPP and Sc_(2)C_(2)@C_(82)⊂[12]***,the temperature-dependent ^(45)Sc nuclear magnetic resonance spectroscopy(NMR)was employed to detect the motion of internal Sc_(3)N and Sc_(2)C_(2) clusters.^(45)Sc NMR results reveal that the[12]CPP can slow down the rotation of internal metallic cluster through host-guest interaction,and thus the[12]CPP can be considered as a molecular brake hoop for the internal metal motion of ***,by means of this molecular brake hoop,the motion of metal atoms inside fullerene cage have expanded range of *** addition,theoretical calculations on Sc_(3)N@C_(80)⊂[12]CPP were executed to illustrate the molecular orientation as well as internal Sc_(3)N *** study would promote the research of endohedral metallofullerene as a molecular rotor.

关键词： metallofullerene molecular rotor molecular brake supramolecular complex dynamic motion

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Ferroelectric,magnetic,and optical properties of Aurivillius compound Bi_(5)FeTi_(2.5)Co_(0.5)O_(15)

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Journal of Materiomics 2018年第4期4卷 353-359页

作者： Hui Sun Yuying Wu Xi Xie yuxi lu Tianshu Yao Jiansheng Zhong Xiaobing Chen College of Physics Science and Technology Yangzhou UniversityYangzhou225002China Guangling College of Yangzhou University Yangzhou225002China

Bi_(5)FeTi_(2.5)Co_(0.5)O_(15)(BFTC)ceramics was successfully synthesized using the sol-gel *** exhibits simultaneously visible-light response,ferroelectric and weak ferromagnetic orders at room *** narrow band gap of 2.06 eV was determined via the UVevis diffuse absorption *** x-ray photoelectron spectroscopy results show that the Fe ions in the samples is 3 t and 2 t valence states while the doped Co ions is 2 t valence *** BFTC sample undergoes a ferromagnetic-like transition at~552 *** ferromagnetism is mainly due to spin-canting of Fe-based and Co-based sublattices via Dzyaloshinskii-Moriya(DM)*** loss and dielectric modulus exhibit the characteristics of dielectric relaxation,which can be ascribed to oxygen/vacancy *** results reveal many potentially useful physical phenomena and open a new avenue to design of novel solar-energy conversion devices and multiferroic applications.

关键词： Aurivillius phase Weak ferromagnetism Optical properties Co-doping

Effects of Ni substitution on multiferroic properties in Bi_(5)FeTi_(3)O_(15) ceramics

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Chinese Physics B 2021年第10期30卷 595-602页

作者： Hui Sun Jiaying Niu Haiying Cheng yuxi lu Zirou Xu Lei Zhang Xiaobing Chen College of Physics Science and Technology Yangzhou UniversityYangzhou 225002China School of Sino-German Engineering Shanghai Technical Institute of Electronics&InformationShanghai 201411China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China

The single-phase multiferroic Bi_(5)Fe_(1−x)NixTi_(3)O_(15)(BFNT-x,x=0,0.1,0.2,0.3,0.4,and 0.5)ceramics were synthesized by a sol-gel auto-combustion method,and their microstructures,ferroelectric,magnetic,and dielectric properties were investigated in *** samples belong to layer-perovskited Aurivillius phase containing four perovskite units sandwiched between two Bi-O *** substitution can not only improve ferroelectricity but also enhance the magnetic *** BFNT-0.2 sample shows the largest remnant polarization(2Pr∼11.6µC/cm^(2))and the highest remnant magnetization(2Mr∼0.244 emu/g).The enhancement of the magnetic properties may mainly originate from the spin canting of Fe/Ni-O octahedra via Dzyaloshinskii-Moriya(DM)*** order to explore the influence of valance state of magnetic ions on the properties,the x-ray photoelectron spectroscopy was carried ***,structural,ferroelectric,and magnetic transitions were also investigated.

关键词： layer-perovskited oxides ferroelectricity weak ferromagnetism phase transition

基于并行全连接卷积神经网络模型的室内可见光信道的最优灯源布局

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光学学报 2022年第13期42卷 35-47页

作者：张慧颖卢宇希梁誉王凯吉林化工学院信息与控制工程学院吉林吉林132022

针对室内LED灯源光强分布不平坦、传统Lambert模型未考虑非直射信道、环境中噪声和干扰、障碍物遮挡、室内边界及不规则房间布局等问题,提出基于并行全连接-卷积神经网络(PFCNN)模型的室内可见光定位(VLP)最优灯源布局方案。通过采集现... 详细信息

针对室内LED灯源光强分布不平坦、传统Lambert模型未考虑非直射信道、环境中噪声和干扰、障碍物遮挡、室内边界及不规则房间布局等问题,提出基于并行全连接-卷积神经网络(PFCNN)模型的室内可见光定位(VLP)最优灯源布局方案。通过采集现场灯源坐标、功率和朝向角等灯源信息及其对应的接收平面光强分布构建指纹库数据集,并用蒙特卡罗方法衡量光强分布平坦度参数;提出采用全连接神经网络和并行全连接神经网络建立可见光信道模型;基于PFCNN模型构建光强平坦度预测模型;采用动量粒子群优化K-Means++(Mot-PSO-K-Means++)算法实现最优灯源布局。仿真分析可知:并行全连接神经网络相比全连接神经网络精确度提升84.69%;在5 m×5 m×3 m的室内空间中,4-LED布局下光强平坦度达到92.00%,光强范围为340~440 lx;12-LED布局下光强平坦度达到91.00%,光强范围为980~1120 lx。该方案有更高的平坦度、较强适用性,可应用于实际室内VLP场景,为室内VLP深入研究提供理论支撑。

关键词：光通信室内可见光信道最优灯源布局全连接神经网络并行全连接-卷积神经网络蒙特卡罗方法 Mot-PSO-K-Means++ 可见光定位

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引入知识增强和对比学习的知识图谱补全

计算机工程 2024年第7期50卷 112-122页

作者：刘娟段友祥陆誉翕张鲁中国石油大学(华东)计算机科学与技术学院山东青岛266580

知识图谱补全是提高知识图谱质量的重要手段,主要分为基于结构和基于描述的方法。基于结构的补全方法对图谱中常见的长尾实体推理性能表现不佳,基于描述的补全方法在描述信息利用和负样本信息学习方面存在不足。针对上述问题,提出基于... 详细信息

知识图谱补全是提高知识图谱质量的重要手段,主要分为基于结构和基于描述的方法。基于结构的补全方法对图谱中常见的长尾实体推理性能表现不佳,基于描述的补全方法在描述信息利用和负样本信息学习方面存在不足。针对上述问题,提出基于知识增强的知识图谱补全方法KEKGC。设计一种特定模板,将三元组及其描述信息通过人工定义的模板转换为连贯的自然语言描述语句输入预训练语言模型,增强语言模型对三元组结构知识与描述知识的理解能力。在此基础上,提出一种对比学习框架来提高链接预测任务的效率与准确率,通过建立记忆库存储实体嵌入向量,从中选择正负样本并结合Info NCE损失进行训练。实验结果显示,相较于MEM-KGC,KEKGC在WN18RR数据集上链接预测任务的平均倒数秩(MRR)提升了5.5,Hits@1、Hits@3、Hits@10指标分别提升了2.8、0.7、4.2个百分点,三元组分类任务准确率达到94.1%,表明所提方法具有更高的预测准确率与更好的泛化能力,尤其对于长尾实体,能够有效提升图谱补全的效果与效率。

关键词：知识图谱预训练语言模型链接预测对比学习实体描述

六角GaM(M=S/Se/Te)的电子结构和力学性质的第一性原理计算

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功能材料 2024年第5期55卷 5134-5140页

作者：路羽茜张鑫李世娜山西大学理论物理研究所太原030006 山西大学量子光学与光量子器件国家重点实验室太原030006 承德应用职业技术学院河北承德067000

依据密度泛函理论(DFT)对层状六角P63/mmc结构的GaM(M=S/Se/Te)进行电子结构与弹性力学特性的模拟研究。优化后的P63/mmc-GaM(M=S/Se/Te)的晶格,与实验结果相吻合。采用HSE06泛函得到的带隙值比PBE得到的与实验值更接近。应变能-应变(E... 详细信息

依据密度泛函理论(DFT)对层状六角P63/mmc结构的GaM(M=S/Se/Te)进行电子结构与弹性力学特性的模拟研究。优化后的P63/mmc-GaM(M=S/Se/Te)的晶格,与实验结果相吻合。采用HSE06泛函得到的带隙值比PBE得到的与实验值更接近。应变能-应变(E-S)和应力-应变(S-S)两种方法得到的P63/mmc-GaM(M=S/Se/Te)的单晶弹性常数都符合弹性力学稳定性准则。在更接近文献值的应力-应变(S-S)法基础上,对3种材料的多晶弹性模量等力学特性进行了后续分析。泊松比和B/G值表明,P63/mmc-GaM(M=S/Se/Te)显现出脆性。各向异性因子、杨氏模量E、剪切模量G及线性压缩系数β的三维立体图分别展示了材料的弹性各向异性程度。在零温零压下,P63/mmc-GaM(M=S/Se/Te)在[100]方向上的第一横向声速最大,在[001]方向上两个横波TA1和TA2的速度最慢。

关键词：密度泛函理论六角P63/mmc-GaM(M=S/Se/Te) 电子结构力学性质各向异性

双水杨醛邻苯二胺柱前衍生-高效液相色谱法测定茶叶中的Pb^(2+)

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色谱 2017年第8期35卷 843-847页

作者：卢玉曦栾锋刘惠涛烟台大学化学化工学院山东烟台264005

建立了利用双水杨醛邻苯二胺希夫碱(SALOPHEN)作为衍生剂结合高效液相色谱(HPLC)测定茶叶中Pb^(2+)含量的方法。Hypersil ODS2 C18反相色谱柱(250 mm×4.6 mm,5μm)为固定相,甲醇-水(80∶20,v/v)为流动相,检测波长为226 nm,反应体系pH为... 详细信息

建立了利用双水杨醛邻苯二胺希夫碱(SALOPHEN)作为衍生剂结合高效液相色谱(HPLC)测定茶叶中Pb^(2+)含量的方法。Hypersil ODS2 C18反相色谱柱(250 mm×4.6 mm,5μm)为固定相,甲醇-水(80∶20,v/v)为流动相,检测波长为226 nm,反应体系pH为10.0。结果表明,样品中Pb^(2+)的线性范围为0.1~30 mg/L,线性相关系数为0.998 8,检出限为0.01 mg/L,加标回收率为91.87%~96.96%。该方法具有较高的灵敏度和稳定性,适用于茶叶中Pb^(2+)的检测。

关键词：高效液相色谱双水杨醛邻苯二胺希夫碱重金属离子茶叶