Y.P.Lu1
,
2) R.F.Zhu1)
,
T.Q.Lei2)
,
Q.S.Ma3)and M.S.Li1) 1) College of Materials Science and Engineering
,
Shandong University of Technology
,
Jinan 250061
,
China2) Harbin Institute of Technology
,
Harbin 150001
,
China 3) Qingrui Oralimplant Center
,
Shandong Provincial Hospital
,
Jinan 250021
,
China
金属学报(英文版)
Theelectron densitiesonsomeplaneofinvolved cellsin αTitanium and Ti Al , Ti 6 Al 4 V and Au Pd Ptalloys werecalculated through EET. Theresultsshow thatthereexist planes withsimilarelectron density amongα Ti,Ti Al,Ti Vand Au Pd Pt unitcells, which veri fiedtosomeextentthe validity ofthe application of EETand atomic boundary condition inTFDtheoryin biomaterials.
关键词:
biomaterial
,
null
,
null
余庚华
,
仲嘉琪
,
王谨
,
詹明生
量子电子学报
doi:10.3969/j.issn.1007-5461.2012.03.001
Ba原子是光频标的候选者之一,对其进行有效的激光冷却与囚禁需要相关能级的寿命和跃迁几率的信息.Ba原子激发态6s6p3P1能级在激光冷却实验中很重要,通过Hanle效应实验测量了这一能级的寿命和自发辐射率,从理论和实验上研究了探测激光有限线宽和光强对Ba原子基态6s21S0与激发态6s6p3P1之间跃迁(波长791nm)Hanle效应荧光信号的影响.在考虑了激光线宽和光强因素后所得到的激发态6s6p3P1的能级寿命和自发辐射率与其他方法给出的结果符合很好.
关键词:
光谱学
,
能级寿命
,
Hanle效应
,
线宽
,
Ba原子
,
原子频标
杨平
,
张传福
,
戴曦
,
樊友奇
,
湛菁
,
蒋伟燕
中国有色金属学报
采用草酸盐前驱体合成Ti4+、Mg2+掺杂正极材料Li(Ni1/3Co1/3-xMn1/3)MxO2(M=Ti, Mg).利用XRD和SEM对其结构和形貌进行表征,并采用循环伏安、交流阻抗、恒流/恒压充放电测试其电化学性能.结果表明:Ti4+、Mg2+掺杂后晶胞体积增大,大倍率充放电时LiNi1/3Co1/3Mn1/3O2的电化学反应阻抗Rct降低,其大倍率充放电性能得到改善,Ti4+掺杂效果更好;当掺杂量x＝0.025时,材料晶型完整,具有单一的a-NaFeO2层状结构;1C倍率时Li(Ni1/3Co1/3-0.025Mn1/3)Ti0.025O2的第二循环放电容量为143.2 mA-h/g,2C时为128.0 mA-h/g,经100次循环后容量分别为132.5和115.8 mA-h/g,容量保持率为92.53%和90.47%.
关键词:
LiNi1/3Co1/3Mn1/3O2
,
锂离子电池
,
正极材料
,
电化学性能
邱元进
,
杨方
,
刘正才
,
林永辉
,
刘素珍
色谱
doi:10.3724/SP.J.1123.2012.01020
建立了畜禽产品中维吉尼亚霉素M1和S1药物残留检测的液相色谱-串联质谱分析方法.样品以甲醇-乙腈溶液(1:1,V/v)提取,上清液经0.01 mol/L磷酸二氢铵溶液稀释后,Oasis HLB固相萃取小柱净化,Luna C18色谱柱分离,以乙腈和含0.1％(体积分数)甲酸的5 mmol/L乙酸铵水溶液作为流动相进行梯度洗脱,电喷雾正离子模式电离(ESI+).多反应监测(MRM)模式检测,外标法定量.该方法对两物质线性范围均为0.15～10.O μg/L,相关系数r2均大于0.999；定量下限均为0.25 μg/kg.在不同基质中,0.25、0.50、2.5 μg/kg 3个添加水平的平均回收率范围为71.2％～98.4％,精密度范围为3.6％～15.4％.该方法具有快速简便、灵敏度高、准确性强等特点,适用于畜禽产品中维吉尼亚霉素的检测.
关键词:
液相色谱-串联质谱(LC-MS/MS)
,
维吉尼亚霉素M1
,
维吉尼亚霉素S1
,
残留
,
畜禽产品
曹笃盟
,
李志友
,
周科朝
稀有金属材料与工程
采用固相反应法制备了Li1+xV3-yMyO8(M=Mo,P;0≤y≤0.4),研究了不同Mo和P含量对Li1+xV3O8相的影响,并首次对其进行了高温阴极放电性能的研究.结果表明:Mo和P掺杂量分别为y≤0.2和y＜0.2时可获得纯Li1+xV3O8相;Mo掺杂使Li1+xV3O8峰值电压提高0.3 V,比容量提高25%,嵌入的Li+量最高可达x=3.8;P掺杂(y≤0.20)对Li1+xV3O8的峰值电压和比容量影响较小.化学嵌锂实验也证实掺杂后的材料具有更快的Li+嵌入速度.
关键词:
Li1+xV3O8
,
热电池
,
掺杂
,
比容量
朱圆金枝
,
钱斌
,
须静怡
,
孔凡军
,
孙蕾
,
韩志达
,
张平
,
杨刚
,
江学范
功能材料
doi:10.3969/j.issn.1001-9731.2014.增刊(Ⅱ).025
利用高温固相反应法制备了新型三元锂离子电池正极材料 Li2 Ru1/3 Co1/3 M1/3 O3(M＝Mn、Ni、Fe)。通过 X 射线衍射技术和电化学性能测试对Li2 Ru1/3 Co1/3 M1/3 O3的微观结构及其电化学性能进行了表征。研究结果表明,Li2 Ru1/3 Co1/3 Ni1/3 O3和Li2 Ru1/3 Co1/3 Fe1/3 O3为六方层状结构,空间群为 R-3M,而 Li2 Ru1/3 Co1/3 Mn1/3 O3保持了单斜结构；电化学性能测试表明 Li2 Ru1/3 Co1/3 Mn1/3 O3的电化学性能优于掺杂Fe和Ni 的三元材料,该材料具有良好的循环性能,在电流密度为16 mA/g 情况下,首次充电容量达到190 mAh/g,首次放电容量为171 mAh/g,50次循环后容量保持率为98％。
关键词:
锂电池
,
Li2Ru1/3Co1/3M1/3O3正极材料
,
结构
,
电化学性能
孙清池
,
左孝杰
,
徐庭献
,
王裕斌
兵器材料科学与工程
doi:10.3969/j.issn.1004-244X.2001.03.002
研究了软性铌锑-锆钛酸铝Pb(Sb1/2 Nb1/2)ZrTiO3(简称SN)系及硬性锑锰-锆钛酸铅Pb(Mn1/3 Sb2/3)ZrTiO3(简称MS)系压电陶瓷电场E3和应变S1的关系.压电方程为S1=d31 E3,在弱电场下为线性关系.随着电场增加,压电应变系数d31变大,从而不再是常数.当电场E3增大到某一值时d31有极大值,我们称此电场为饱和电场Es.软性SN三元系压电陶瓷的退极化电场Ed为12.7kV/cm,小于它的矫顽场Ec(13.6kV/cm)以及d31极大值(-457pC/N)时的饱和电场Es(14kV/cm).而硬性MS三元系压电陶瓷的退极化电场Ed和d31极大值(-202pC/N)时的饱和电场Es相等,均为24kV/cm,大于它的矫顽电场Ec(18.6kV/cm).软性SN三元系压电陶瓷在较低的电场下就可产生很大的应变.而硬性MS三元系压电陶瓷可以施加很大的反向电场.
关键词:
压电应变系数D31
,
退极化电场Ed
,
矫顽电场Ec
,
饱和电场Es
,
电滞回线
Journal of Physical Chemistry A
The temperature dependence of magnetic susceptibility and sublattice magnetizations were calculated for a Heisenberg Hamiltonian of an S = 1 and S = 1/2 antiferromagnetic alternating spin chain by means of the many-body Green's function theory to show the possible occurrence of a ferrimagnetic phase transition for genuinely organic molecule-based magnets. The S = 1 site in the chain is composed of two S = 1/2 spins coupled by a finite ferromagnetic interaction. From the calculated results, it is found that the sublattice magnetization at low-spin S = 1/2 sites changes its sign from negative to positive with increasing temperature, giving rise to the spin alignments along the chain changing from anti ferromagnetic to ferromagnetic ones, which indicates that there is a magnetic phase transition occurring. Because of the weak intermolecular anti ferromagnetic interactions, the curves of the magnetic susceptibility multiplied by temperature (chi T) against temperature show a round peak at low temperatures, which is well consistent with recent experimental observations, and the ferrimagnetic phase transition could only be detected at an ultralow-temperature region and under very weak,external magnetic fields in practical organic materials. From the analysis of the sublattice magnetizations, it is uncovered that the appearance of the low-temperature peak in the curves of the chi T originates from the ferromagnetic spin alignments for all the spins along the chain, and the intermolecular antiferromagnetic interactions play a pivotal role in ferrimagnetic spin alignments of the magnetic systems. It is also found that the higher spatial symmetry of the intermolecular antiferromagnetic interactions have contributions to stabilize the ferrimagnetic ordering state in the molecule-based magnetic materials.
关键词:
nitrophenyl nitronyl nitroxide;simple classical pictures;numerical-calculations;composite molecules;magnetic-properties;building-blocks;ground-state;component;model;system
