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The stabilization effect of the substituted atoms and the magnetism for intermetallic compounds YFe_(12-x)V_x

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Science China(Physics,Mechanics & Astronomy) 2010年第7期53卷 1239-1243页

作者： MA HuanFeng HUANG Zheng CHEN Bo QIANG WeiRong sun guangai School of Physics Science and Technology Southwest Jiaotong UniversityChengdu 610031China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

Based on the density functional theory(DFT),using linearized augmented plane wave and improved local orbital(APW+lo),the structures and energies of Y,Fe,V,FeV,YFe12-xVx,and Y2Fe17 are optimized and *** is explained that the pure YFe12 with ThMn12-type structure does not exist,and replacing a small fraction of vanadium can stabilize the *** local magnetic moments reveal that the decrease of magnetization of YFe12-xVx does not only correspond to a simple dilution of the iron sublattice magnetization,but also reduce the Fe moments as well with increasing vanadium content.

关键词： YFe12-xVx density functional theory(DFT) magnetic moment stabilization

A neutron diffraction investigation of high valent doped barium ferrite with wideband tunable microwave absorption

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Journal of Advanced Ceramics 2022年第2期11卷 263-272页

作者： Jun LI Yang HONG San HE Weike LI Han BAI Yuanhua XIA guangai sun Zhongxiang ZHOU School of Physics Harbin Institute of TechnologyHarbin 150001China Heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology Harbin Institute of TechnologyHarbin 150001China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory for Neutron Physics of CAEP Institute of Nuclear Physics and ChemistryMianyang 621999China

The barium ferrite BaTi_(x)Fe_(12−x)O_(19)(x=0.2,0.4,0.6,0.8)(BFTO-x)ceramics doped by Ti4+were synthesized by a modified sol–gel *** crystal structure and magnetic structure of the samples were determined by neutron diffraction,and confirm that the BFTO-x ceramics were high quality single phase with sheet *** x increasing from 0.2 to 0.8,the saturation magnetization(M_(s))decreases gradually but the change trend of coercivity(H_(c))is complex under the synergy of the changed grain size and the magnetic crystal anisotropy *** on the high valence of Ti^(4+),double resonance peaks are obtained in the curves of the imaginary part of magnetic conductivity(μ′′)and the resonance peaks could move toward the low frequency with the increase of x,which facilitate the samples perform an excellent wideband modulation microwave absorption *** the x=0.2 sample,the maximum reflection loss(RL)can reach−44.9 dB at the thickness of only 1.8 mm,and the bandwidth could reach 5.28 GHz at 2 mm when RL is less than−10 *** the BFTO-x ceramics show excellent frequency modulation ability varying from 18(x=0.8)to 4 GHz(x=0.4),which covers 81%of the investigated frequency in microwave absorption *** work not only implements the tunable of electromagnetic parameters but also broadens the application of high-performance microwave absorption devices.

关键词： barium ferrite neutron diffraction microwave absorption

Chelating agents role on phase formation and surface morphology of single orthorhombic YMn_2O_5 nanorods via modified polyacrylamide gel route

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Science China Chemistry 2014年第3期57卷 402-408页

作者： WANG ShiFa ZHANG ChuanFei sun guangai CHEN Bo XIANG Xia DING QingPing ZU XiaoTao School of Physical Electronics University of Electronic Science and Technology of China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics

YMn2O5nanorods were synthesized through a modified polyacrylamide gel *** synthesis strategy in this work is based on a sol-gel process using a polyacrylamide gel method in which oxalic acid,citric acid or tartaric acid is employed as the chelating *** the gel routes,oxalic acid was used as a carboxyl chelating agent,while citric acid or tartaric acid was a carboxyl and hydroxyl chelating *** as-prepared samples were characterized by means of techniques such as X-ray powder diffraction(XRD)measurement,thermogravimetric analysis(TG),differential scanning calorimetry analysis(DSC),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),thermal expansion measurement and field-emission scanning electron microscopy(SEM)*** was found that oxalic acid is the best chelating agent with Y(NO3)3·6H2O and Mn(CH3COO)2·4H2O as precursors to prepare a single orthorhombic YMn2O5nanorods at 1000°*** electron microscope observation shows that the morphology of YMn2O5powders is significantly dependent on the chelating *** peaks(single orthorhombic YMn2O5nanorods)at 642,600,573,546,521,493,486,468,448 and 400cm?1were observed from FTIR *** phase,surface morphology and chelation mechanisms of YMn2O5samples have been discussed on the basis of the experimental results.

关键词： YMn2O5 chelating agent thermal expansion nanorods

Effects of deuteration on the structure of NH_4H_2PO_4 crystals characterized by neutron diffraction

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Chinese Physics B 2019年第1期28卷 484-489页

作者： Baoan Liu Lili Zhu Fafu Liu Xun sun Xiping Chen Lei Xie Yuanhua Xia guangai sun Xin Ju Department of Physics University of Science and Technology Beijing School of Materials Science and Engineering Shandong Jiaotong University State Key Laboratory of Crystal Materials Shandong University Neutron Physics Laboratory China Academy of Engineering Physics

A series of deuterated ammonium dihydrogen phosphate(DADP) crystals were grown and their structures were investigated by using powder neutron diffraction method. In the entire composition range, the deuterated level in the crystals is lower compared with the aqueous growth solution. The deuterium segregation coefficient in the crystals decreases with increasing deuterium content of the solution. The deuterium content in the NH_4^+ group is higher than that in H_2PO_4^- *** addition, the variations of lattice parameters are shown here.

关键词： DADP crystal neutron diffraction deuteration level

聚丙烯酰胺凝胶合成尖晶石纳米铝酸锌的络合机理及发光性能

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材料研究学报 2015年第10期29卷 721-728页

作者：孙光壮王仕发孙光爱向霞祖小涛中国工程物理研究院核物理与化学研究所绵阳621900 电子科技大学物理电子学院成都610054

用改进的聚丙烯酰胺凝胶法制备颗粒近似呈球形且粒度均匀的ZnAl2O4纳米颗粒,并制备了3种锌铝摩尔比的ZnAlO样品。XRD结果表明,当锌铝摩尔比为1∶1.8和1∶2时,在900℃煅烧干凝胶制备的样品均为纯相的ZnAl2O4粉体。SEM结果表明,锌铝摩尔比... 详细信息

用改进的聚丙烯酰胺凝胶法制备颗粒近似呈球形且粒度均匀的ZnAl2O4纳米颗粒,并制备了3种锌铝摩尔比的ZnAlO样品。XRD结果表明,当锌铝摩尔比为1∶1.8和1∶2时,在900℃煅烧干凝胶制备的样品均为纯相的ZnAl2O4粉体。SEM结果表明,锌铝摩尔比为1∶2制备的样品其颗粒尺寸随着煅烧温度的提高而增大,且在900℃出现严重的团聚。荧光光谱分析结果表明,激发波长为352nm时出现一个469nm的蓝光发射峰。基于实验结果,研究了其络合机理和发光机理。

关键词：无机非金属材料聚丙烯酰胺凝胶法 ZnAl2 O4 蓝光发射络合机理

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中子散射技术在化学研究中的应用

中国科学：化学 2023年第11期53卷 2237-2249页

作者：刘栋孙光爱彭述明中国工程物理研究院核物理与化学研究所绵阳621999

中子散射在化学、软物质、基础物理、地球科学、工程等领域应用广泛,在不同领域的科学探索过程中发挥了关键作用.中子具有不带电荷、穿透能力强、对轻元素敏感、能够进行无损检测等特点.一方面,弹性中子散射在氢元素富集的化学材料体系... 详细信息

中子散射在化学、软物质、基础物理、地球科学、工程等领域应用广泛,在不同领域的科学探索过程中发挥了关键作用.中子具有不带电荷、穿透能力强、对轻元素敏感、能够进行无损检测等特点.一方面,弹性中子散射在氢元素富集的化学材料体系、高分子体系、生物大分子等体系的结构研究中独具优势;另一方面,非弹性中子散射测量的能量、散射矢量范围与这类材料体系的时间、空间尺度吻合,非常适合化学过程的动力学研究.本文将通过结合中国绵阳研究堆(CMRR)中子散射平台上的应用实例,重点介绍国内外利用小角中子散射、中子反射、中子衍射、非弹/准弹性中子散射等代表性技术在化学反应机理研究、溶液中的化学过程、高分子化学、生物化学、材料化学、核化学和放射化学等领域的典型应用及前景.

关键词：中国绵阳研究堆中子科学平台中子散射化学软物质

D_yFe_(10)Si_2N_x化合物的结构与磁性

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材料研究学报 2006年第3期20卷 327-332页

作者：孙光爱陈波吴二冬杜红林孙凯中国工程物理研究院核物理与化学研究所绵阳621900 中国科学院金属研究所沈阳材料科学国家(联合)实验室沈阳110016 北京大学物理学院北京100871 中国原子能科学研究院核物理所北京102413

利用中子粉末衍射技术确定了77 K温度下化合物中Si原子占位和原子磁矩,研究了DyFe10Si2化合物低温下的结构与磁性．结果表明,在77 K化合物的易磁化方向与ab平面之间有较小的夹角．采用全势能线性缀加平面波((L)APW)+局域轨道(10)方法计... 详细信息

利用中子粉末衍射技术确定了77 K温度下化合物中Si原子占位和原子磁矩,研究了DyFe10Si2化合物低温下的结构与磁性．结果表明,在77 K化合物的易磁化方向与ab平面之间有较小的夹角．采用全势能线性缀加平面波((L)APW)+局域轨道(10)方法计算了DyFe10Si2及其氮化物的磁性和间隙原子效应,分析了化合物中间隙N原子在Si原子不同占位时的作用．结果表明,N原子的杂化作用能提高化合物的饱和磁矩(不显著),使其居里温度有显著的提高(15％-20％)．

关键词：金属材料,DyFe10Si2Nx化合物(x=0,1),中子衍射,(L)APW+lo方法,结构与磁性

利用径向准直器减轻中子应力测量中的赝偏移的模拟研究

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核技术 2012年第2期35卷 117-120页

作者：陈彦舟孙光爱陈波中国工程物理研究院核物理与化学研究所绵阳621900

用中子衍射应力分析谱仪测量无应力样品表面时,衍射峰因装置因素会发生一定的偏移(赝偏移)。使用射线追踪程序SIMRES对减轻赝偏移的方法进行系统研究,使得测量的应力值更为准确且具有重要的实用价值。研究结果表明,使用第一和第二径向... 详细信息

用中子衍射应力分析谱仪测量无应力样品表面时,衍射峰因装置因素会发生一定的偏移(赝偏移)。使用射线追踪程序SIMRES对减轻赝偏移的方法进行系统研究,使得测量的应力值更为准确且具有重要的实用价值。研究结果表明,使用第一和第二径向准直器可有效减轻赝偏移,主要体现在第一径向准直器可以减轻波长效应,第二径向准直器可以减轻峰剪切效应。

关键词：中子衍射应力分析赝偏移径向准直

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SnO_2纳米颗粒的制备及其发光性能

材料研究学报 2014年第6期28卷 420-426页

作者：王云王虹孙光爱陈喜平王仕发中国工程物理研究院核物理与化学研究所绵阳621900

用大分子网络凝胶法合成了氧化锡(SnO2)纳米颗粒。X射线衍射(XRD)结果表明,合成的SnO2纳米颗粒具有四方金红石结构,不含任何杂质相。扫描电镜(SEM)观察发现,制得的SnO2纳米颗粒形貌规整、呈类菱形。荧光光谱结果表明,在326 nm波长的光... 详细信息

用大分子网络凝胶法合成了氧化锡(SnO2)纳米颗粒。X射线衍射(XRD)结果表明,合成的SnO2纳米颗粒具有四方金红石结构,不含任何杂质相。扫描电镜(SEM)观察发现,制得的SnO2纳米颗粒形貌规整、呈类菱形。荧光光谱结果表明,在326 nm波长的光激发下,其荧光光谱由四个主发射带组成,其峰值分别位于379,417,450,470 nm。用230 nm波长的光激发,得到一个740 nm的荧光发射峰。基于实验结果,探讨了纳米SnO2的形成机理和发光机制。

关键词：无机非金属材料大分子网络凝胶法 SnO2 纳米颗粒发光机制