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Science China(Physics,Mechanics & Astronomy) 2020年第9期63卷 105-110页

作者： Ning An Meng Tang Shuai Hu HuangLin Yang WeiJia Fan ShiMing Zhou xuepeng qiu Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092China

Antiferromagnets(AFMs)with chiral noncollinear spin structure have attracted great attention in recent ***,the existing research has mainly focused on hexagonal chiral AFMs,such as Mn3Sn,Mn3Ga,Mn3Ge with low crystalline ***,we present our systematical study for the face-centered cubic noncollinear antiferromagnetic *** varying the alloy composition(x),we have successfully fabricated antiferromagnetic Mn1-xPtx epitaxial films on MgO substrates and have observed a crystalline structure transition from L10 MnPt to L12 *** Mn3Pt exhibits a large anomalous Hall effect,which is in the same order of magnitude as those of ferromagnetic ***,a large thickness-evolved strain effect is revealed in Mn3Pt films by X-ray diffraction(XRD)analysis based on the Scherrer *** work explores Mn3Pt as a promising candidate for topological antiferromagnetic spintronics.

关键词： anomalous Hall effect noncollinear antiferromagnet strain effect L10 and L12 alloys

Effect of Draw Ratio on the Morphologies and Properties of BPDA/PMDA/ODA Polyimide Fibers

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Chemical Research in Chinese Universities 2014年第1期30卷 163-167页

作者： ZHANG Chunling ZHANG Qiong XUE Yanhu LI Guomin LIU Fangfang qiu xuepeng JI Xiangling GAO Lianxun College of Materials Science and Engineering Jilin University Changchun 130025 P. R. China Polymer Composite Engineering Laboratory Chinese Academy of Sciences Changchun 130022 P. R. China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 R R. China

3,3,4,4-Biphenyltetracarboxylic dianhydride/pyromellitic dianhydride/4,4-oxydianiline（BPDA/PMDA/ODA） polyimide copolymer fibers with different draw ratios were prepared from the imidization of polyacrylic acid（PAA） fibers via a dry-jet wet-spinning *** morphologies,microcrystal orientations,thermal stabilities,and mechanical properties were investigated via scanning electron microscopy（SEM）,wide angle X-ray diffraction（WAXD）,thermogravimetric analysis（TGA）,and tensile *** order to acquire fibers with better mechanical performance,we aimed at obtaining the optimal draw *** during thermal imidization resulted in a decreased diameter of fiber from 25.8 μm to 16.9 μm corresponding to draw ratio from 1 to *** results show that the degree of the orientation of the undrawn sample is 64.1％,whereas that of the drawn sample is up to 82％.The as-spun fiber and those with different draw ratios all exhibit high thermal stabilities,i.e.,the temperature at a mass loss of 5％ can reach as high as 570 ℃.The tensile strengths and tensile modulus of the fibers increase with the draw ratios,and the maximum tensile strength and modulus are 0.90 and 12.61 GPa,respectively.

关键词： Polyimide Draw ratio Morphology Orientation Mechanical property

Preparation and Properties of Imidazole-containing Polyimide/Silica Hybrid Films

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Chemical Research in Chinese Universities 2014年第6期30卷 1047-1050页

作者： MA Xiaoye MA Xiaofei qiu xuepeng LIU Fangfang JIN Rizhe KANG Chuanqing GUO Haiquan GAO Lianxun Polymer Composite Engineering Laboratory Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China" CAST- Xi 'an Institute of Space Radio Technology China Academy of Space Technology Xi' an 710000 P. R. China

Imidazole-containing polyimide/silica（PI/SiO2） hybrid films were prepared from 3,3＇,4,4＇-biphenyltetra- carboxylic dianhydride（BPDA） and 2,2＇-di（p-aminophenyl）-5,5＇-bibenzimidazole in N,N-dimethylacetamide（DMAc） by sol-gel method and thermal imidization. The hybrid film with high silica mass fraction up to 40% was transparent. Scanning electron microscope（SEM） and transmission electron microscope（TEM） results of the film indicate a ho- mogeneous dispersion of silica nanoparticles in the polyimide matrix. One hybrid film PI/SiO2 with 15% SiO2 exhi- bits better mechanical properties with a tensile strength of 222 MPa, an elongation at break of 12%, and a tensile modulus of 5.66 GPa. The reinforced mechanism on mechanical Drooerties was also studied.

关键词： Polyimide Silica Benzimidazole Sol-gel method

Promotion Mechanism of H2O for Stereoselectivity in Pd(Ⅱ)-catalyzed C—H Aryiation of Diarylphosphinamides with Arylboronic Acids

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Chemical Research in Chinese Universities 2020年第5期36卷 843-846页

作者： CAI Yanchun JIAO Long qiu Xuepcng DU Zhijun Polymer Composites Engineering laboratory Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

On the basis of a series of control experiments and nuclear magnetic resonance analyses,it is discovered that Boc-protected amino acid ligand coordinated to Pd center is partly replaced by N,N-dimethylformamide,and H2O can inhibit coordination of N,N-dimethylformamide to Pd *** novel action mechanism perfectly explains H2O promotion for stereoselectivity in Pd(II)-catalyzed C—H aryiation of diarylphosphinamides with arylboronic acids.

关键词： C-H activation Stereoselectivity Water Ligand exchange

Ni-Catalyzed Cross Coupling ofAryl Grignard Reagents with Aryl Halides in a Nonpolar Solvent and an Efficient Synthesis of Biaryls Under Neat Conditions

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Chemical Research in Chinese Universities 2016年第1期32卷 55-61页

作者： WU Qiang JIN Rizhe KANG Chuanqing CHEN Wenhui BIAN Zheng MA Xiaoye DING Jinying GUO Haiquan qiu xuepeng GAO Llanxun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China University of Chinese Academy of Sciences Beo'ing 100864 P. R. China

This study details Ni-catalyzed cross coupling of aryl Grignard reagents with aryl halides in toluene, a nonpolar solvent with a high boiling point. The reaction was applied for the synthesis of various biaryls in good yields without the introduction of a large steric ligand. The Kumada-Tamao-Corriu（KTC） reaction in toluene was then successfully modified to proceed under neat conditions for the efficient syntheses of symmetrical biaryls, particularly in large-scale preparations. Unactivated aryl chlorides show higher reactivity than aryl bromides, particularly under neat conditions. Mechanistic investigations suggest a radical procedure for the catalytic cycle, and the origin of the radical intermediates being aryl halides.

关键词： Cross-coupling Nickel Biaryl Reaction mechanism Neat condition

热亚胺化过程中气氛和拉力对BPDA-PDA聚酰亚胺纤维结构与性能的影响

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高等学校化学学报 2017年第1期38卷 150-158页

作者：杨文轲刘芳芳张恩菘邱雪鹏姬相玲中国科学院长春应用化学研究所高分子物理与化学国家重点实验室高分子复合材料工程实验室长春130022 中国科学院大学北京100049

研究了3,3',4,4'-联苯四酸二酐-对苯二胺(BPDA-PDA)型聚酰胺酸(PAA)纤维热亚胺化过程中气氛和拉力对聚酰亚胺(PI)纤维结构和性能的影响.热处理过程中,恒温处理5 min时,虽然不同气氛下纤维的表面形貌并无明显差异,但N_2气下所得纤维的力... 详细信息

研究了3,3',4,4'-联苯四酸二酐-对苯二胺(BPDA-PDA)型聚酰胺酸(PAA)纤维热亚胺化过程中气氛和拉力对聚酰亚胺(PI)纤维结构和性能的影响.热处理过程中,恒温处理5 min时,虽然不同气氛下纤维的表面形貌并无明显差异,但N_2气下所得纤维的力学性能明显优于空气下的样品,N2气保护作用下,最高断裂强度和初始模量分别达到1.25和65.0 GPa.恒温处理40 min时,N_2气对纤维表面形貌有明显的保护作用.但对于力学性能,气氛的影响仅在450℃时表现得非常明显.低于450℃时,长时间的热处理成为影响纤维力学性能的主要因素,气氛的影响变得不明显.高于450℃时,在N_2气和空气中的纤维皆发生明显的降解,从而严重影响其力学性能.热亚胺化过程中施加的拉力会促进纤维热酰亚胺化过程中的膨胀.随着拉力的增加PI纤维长度增加,同时直径减小.PI纤维轴上(004)晶面的间距、晶粒尺寸、线性热膨胀系数(为负值)的绝对值及玻璃化转变温度都随热处理时拉力的增加而增大.纤维的断裂强度随拉力的变化基本保持在0.90GPa左右,断裂伸长率随着拉力增加稍有下降,纤维的初始模量随拉力的增大而增加.

关键词：聚酰亚胺纤维聚酰胺酸热亚胺化气氛拉力

基于氟碳表面活性剂插层水滑石的聚酰亚胺纳米复合材料的制备与性能

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高等学校化学学报 2016年第2期37卷 403-408页

作者：郭海泉马晓野金日哲康传清邱雪鹏高连勋中国科学院长春应用化学研究所高分子物理与化学国家重点实验室长春130024 中国科学院大学北京100039

以氟碳表面活性剂全氟辛基磺酸钾为插层剂,通过离子交换制备插层水滑石,并以其为填料,通过原位插层聚合方法,制备了水滑石/氟碳表面活性剂/聚酰亚胺纳米复合材料.用X射线衍射、红外光谱和热失重等方法分析插层水滑石结构.结果表明,全氟... 详细信息

以氟碳表面活性剂全氟辛基磺酸钾为插层剂,通过离子交换制备插层水滑石,并以其为填料,通过原位插层聚合方法,制备了水滑石/氟碳表面活性剂/聚酰亚胺纳米复合材料.用X射线衍射、红外光谱和热失重等方法分析插层水滑石结构.结果表明,全氟辛基磺酸钾插层水滑石后,水滑石的层间距由0.76 nm增加到2.52 nm,在水滑石层间构建了氟碳链的微环境.这种氟化水滑石可剥离分散于聚酰亚胺基体中,改善了纳米复合材料的气体阻隔性能、介电性能和机械性能.这种影响不仅体现无机纳米片层的杂化效果,而且展示出氟碳链的特点.

关键词：氟碳表面活性剂水滑石聚酰亚胺纳米复合材料

Antisymmetric planar Hall effect in rutile oxide films induced by the Lorentz force

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Science Bulletin 2024年第15期69卷 2362-2369页

作者： Yongwei Cui Zhaoqing Li Haoran Chen Yunzhuo Wu Yue Chen Ke Pei Tong Wu Nian Xie Renchao Che xuepeng qiu Yi Liu Zhe Yuan Yizheng Wu Department of Physics State Key Laboratory of Surface PhysicsFudan UniversityShanghai 200433China Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan UniversityShanghai 200433China Center for Advanced Quantum Studies and Department of Physics Beijing Normal UniversityBeijing 100875China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438China Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092China Zhejiang Laboratory Hangzhou 311100China Shanghai Research Center for Quantum Sciences Shanghai 201315China Shanghai Key Laboratory of Metasurfaces for Light Manipulation Fudan UniversityShanghai 200433China

The conventional Hall effect is linearly proportional to the field component or magnetization component perpendicular to a film. Despite the increasing theoretical proposals on the Hall effect to the in-plane field or magnetization in various special systems induced by the Berry curvature, such an unconventional Hall effect has only been experimentally reported in Weyl semimetals and in a heterodimensional superlattice. Here, we report an unambiguous experimental observation of the antisymmetric planar Hall effect(APHE) with respect to the in-plane magnetic field in centrosymmetric rutile RuO_(2) and IrO_(2) single-crystal films. The measured Hall resistivity is found to be linearly proportional to the component of the applied in-plane magnetic field along a particular crystal axis and to be independent of the current direction or temperature. Both the experimental observations and theoretical calculations confirm that the APHE in rutile oxide films is induced by the Lorentz force. Our findings can be generalized to ferromagnetic materials for the discovery of anomalous Hall effects and quantum anomalous Hall effects induced by in-plane magnetization. In addition to significantly expanding knowledge of the Hall effect, this work opens the door to explore new members in the Hall effect family.

关键词： Antisymmetric planar Hall effect Lorentz force Rutile oxide films Crystal symmetry

碳纤维三向织物/环氧树脂复合材料的制备与力学性能

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高等学校化学学报 2020年第4期41卷 838-845页

作者：沙迪禹旭敏赵将马小飞王汉夫刘芳芳邱雪鹏中国科学院长春应用化学研究所高分子复合材料工程实验室长春130022 中国空间技术研究院西安分院西安710100 中国科学院长春应用化学研究所高分子物理与化学国家重点实验室长春130022

选择不同纱线间距[即二经(纬)纱之间的中心距]尺寸的碳纤维三向织物,采用热压成型技术制备了碳纤维三向织物/环氧树脂复合材料.研究了纱线间距及样品裁剪角度等对力学性能的影响,并与碳纤维二向织物/环氧树脂复合材料的力学性能进行对比... 详细信息

选择不同纱线间距[即二经(纬)纱之间的中心距]尺寸的碳纤维三向织物,采用热压成型技术制备了碳纤维三向织物/环氧树脂复合材料.研究了纱线间距及样品裁剪角度等对力学性能的影响,并与碳纤维二向织物/环氧树脂复合材料的力学性能进行对比.结果表明,随着纱线间距尺寸从2 mm增加到6 mm,0°方向断裂强度从221.7 MPa下降到148.1 MPa,撕裂强力从1000 N下降到600 N;90°方向断裂强度从50.0 MPa下降到22.1 MPa,撕裂强力从330 N下降到100 N;顶破强力从424 N下降到216 N.这些力学性能的逐渐降低是单位面积的碳纤维增强体含量减少和织物的孔洞增大共同作用的结果.纱线间距为2 mm的碳纤维三向织物复合材料在0°(以纬纱为基准),30°,45°,60°和90°方向的断裂强度分别为221.7,48.5,44.3,227.7和50.0 MPa,即断裂强度在0°和60°方向大于在30°,45°及90°方向.由三向织物的编织原理可知,0°与60°方向完全相同,因此其断裂强度相似,且样品中有一组纱线与外加载荷平行,对形变破坏具有一定的约束作用,而30°,45°和90°方向样品中三组纱线所在的方向均和外加载荷存在一定的夹角,有效分散外加载荷的能力减弱.对比碳纤维三向织物/环氧树脂复合材料与碳纤维二向织物/环氧树脂复合材料的断裂强度、撕裂强力和顶破强力发现,前者的综合性能明显优于后者,碳纤维三向织物/环氧树脂复合材料的断裂强度、撕裂强力、顶破强力分别为221.7 MPa,1000 N和424 N,三向织物的优势得到凸显,为后续制备多种类型的碳纤维三向织物复合材料及应用奠定了基础.

关键词：碳纤维三向织物环氧树脂复合材料力学性能

基于2,5-二(4-氨基苯)嘧啶聚酰亚胺的合成及性能表征

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高分子学报 2007年第3期17卷 262-266页

作者：夏爱香吕光华邱雪鹏丁孟贤高连勋中国科学院长春应用化学研究所高分子物理与化学国家重点实验室

1,5-二氮杂戊二烯盐(vinamidium salts)与4-硝基苯甲脒盐在碱性物质的存在下发生成环反应得含嘧啶环的硝基化合物;硝基化合物用Pd/C和水合肼还原得到棒状含氮芳杂环二胺——2,5-二(4-氨基苯基)嘧啶.通过1H-NMR,13C-NMR,IR,MS及元素分析... 详细信息

1,5-二氮杂戊二烯盐(vinamidium salts)与4-硝基苯甲脒盐在碱性物质的存在下发生成环反应得含嘧啶环的硝基化合物;硝基化合物用Pd/C和水合肼还原得到棒状含氮芳杂环二胺——2,5-二(4-氨基苯基)嘧啶.通过1H-NMR,13C-NMR,IR,MS及元素分析确证了含氮芳杂环二胺及其中间产物的结构.这种二胺或加一定量对苯二胺与均苯二酐(PMDA)或联苯二酐(BPDA)通过两步法聚合获得一系列聚酰亚胺,通过红外、动态力学、静态力学、热重分析、广角X射线衍射等实验测试了该类聚合物的结构、热性能、机械性能及结晶性能.

关键词：聚酰亚胺嘧啶热性能机械性能