自动赛波特比色仪在油品分析中的应用研究

介绍了自动赛波特比色的分析原理及测定油品颜色时的注意事项,测定了同-样品的手动和自动测定结果,并进行了两个方法的比较.分析了手动和自动比色仪各自在测试样品时产生误差的原因,提出了较好的解决办法.     

PHASE DEPENDENCE OF LUMINESCENT EMISSION OF Eu2+ DOPED SrAl2O4

In this work, we made five samples of SrAl₂O₄: Eu²⁺, Dy³⁺, the α phase and β phase SrAl₂O₄:Eu²⁺,Dy³⁺ powder and pellet samples, and α phase single crystal. We have measured the emission spectra of all the samples. All the emission peaks are around 520 nm, which correspond to the transition from 4f⁶5d¹(²E_g) to 4f⁷(⁸S_7/2) of Eu²⁺ in SrAl₂O₄ host. The intensity of emission of the β phase is stronger than that of the α phase. We believe that it is because the Eu²⁺ ions have occupied the two types of sites in the α phase SrAl₂O₄ host and the lifetime of the transition of Eu²⁺ in the A site is longer than that in the B site. This result also proves that the β phase of the material is brighter than the α phase. In addition, the β phase can be achieved by quenching technique.     

结构稳定的高质量荧光材料CaAl_4O_7:Tb~(3+),Ce~(3+)

在本文中制作了CaAl4 O7:Tb3+,Ce3+新荧光材料。烧结温度为 130 0℃ ,烧结环境为N2 + 5 %H2还原气。TEM实验结果表明样品的粒度小于 1μm。X 射线和HRTEM实验证实 ,样品的晶格点阵十分规则 ,而且没有发现掺杂和助溶剂对基质结构的影响 ,表现出十分好的材料质量。光学实验观测到对应于Tb3+离子的 5D4 到7FJ(J=6 ,5 ,4,3) 的跃迁发射峰在 485 ,5 45 ,5 90和 6 2 0nm。CaAl4 O7:Tb3+,Ce3 +降低了基质结构的不确定性 ,同时保持了Tb3+发光中心的特性。     

LUMINESCENCE OF Bi3+ and Eu2+ DOUBLE CENTERS DOPED IN CaS HOST

In this work, double-center.doped luminescent material CaS:Bi³⁺, Eu²⁺ was made via flux NH₄Cl by sintering in excess sulfur environment. The sample had a purplish red net luminescent color. Excitation spectra at both red, 650 nm and blue, 487 nrn were taken. The red emission from Eu²⁺ center was mainly come from the 4f⁶5d¹ absorption in the CaS host. The blue emission from the Bi³⁺ center on the other hand showed no big difference from the singly doped CaS:Bi³⁺ materials in excitation spectrum. Emission spectra were obtained at excitaton of 270nm and 300nm. Stokes shift was moved about 20-30nm, under different point excitation. Emission peaks of both Bi³⁺ and Eu²⁺ centers appeared at 463nm, 642.5nm by 270nm excitation and 487 nm, 620 nm by 300 nm excitation respectively. After-glow decay cures were also obtained and the shapes of decay curves are similar and it is due to the single hole-trap system by lattice defects.     

近红外光谱法测定缓释制剂中冰片释放量

利用近红外光谱技术与化学计量学方法建立了冰片缓释样品近红外光谱与冰片浓度之间的定量模型,以实现冰片释放量的快速测定。配制与缓释制剂具有相同物质体系的的冰片醇水溶液,获取其近红外光谱,采用偏最小二乘法(PLS)建立冰片含量预测模型并考察了图谱类型、建模样品浓度及建模区间对校正模型和预测结果的影响。结果表明采用原始近红外光谱,在5 314～7 032 cm-1区间,将样品按照中高浓度、低浓度范围建模可以获得最佳校正结果与预测结果。最后采用所建的中高浓度区模型测定了冰片包合物在醇水体系中冰片含量,实现了对缓释制剂冰片累加释放量的快速测定,可为冰片缓释制剂的研发快速提供评价数据。     

片状放大器中片间空气间隔对小尺度自聚焦的影响

从非线性Schr?dinger方程出发,根据线性的近似分析方法,通过把介质片厚度和片间空气间隔转化为线性与非线性传输距离比讨论了系统B积分值和空气间隔对非线性增益谱的影响.着重分析了激光介质片数以及B积分值和非线性增长率之间的关系,并讨论了增长率随B积分值与片数的变化规律.其他参量不变的情况下,片间空气间隔的增大,使增益谱向长波方向移动,而介质片数则对增益谱的最高增益和谱线位置都有影响.同时,对这一现象做了无空气间隔的等效模拟.     

An Orthorhombic Polymorph of Lanthanum Ultraphosphate LaP_5O_（14）：Synthesis, Structure and Density Functional Study

An orthorhombic polymorph of lanthanum ultraphosphate, LaP5O14, was firstly synthesized by the high temperature solid-state reaction and structurally characterized by single-crystal X-ray diffraction technique. It crystallizes in the orthorhombic Pmna space group with a=13.155(3), b=8.816(2), c=9.115(2) , V=1057.1(4) 3 and Z=4. The structure features (P5O14)3-anionic ribbons linked with neighboring LaO8 polyhedra. The title solid-state compound is an insulator. Theoretically calculated energy band structure, density of states (DOS), and optical response function by density function theory (DFT) for LaP5O14 were also performed.     

迁移管形状对希托夫法测定离子迁移数结果的影响

在希托夫法测定Cu~(2+)离子迁移数的物理化学实验教学中,目前常用直形和U形两种类型的迁移管,其中使用U形迁移管从阴极区溶液浓度变化算出的迁移数误差较大。以CuSO_4为电解质,Cu电极为电解电极,采用分光光度法分别测定了通电后直形、U形和n形三种迁移管中CuSO_4溶液浓度随高度的分布情况。研究发现,迁移管的形状对中部区溶液的浓度有较大影响。对于U形和n形迁移管,由于阴极位于迁移管底部,主要受重力作用引起的对流因素的影响,通电后中部区浓度会发生明显改变,并影响到阴极区溶液浓度,导致误差较大;使用直形迁移管受该因素的影响很小,能得到更为准确的结果。     

用高阶对比度研究光束的小尺度自聚焦

提出了高阶对比度这一新参数来描述光束的近场均匀性，并用之研究高功率激光装置中的小 尺度自聚焦现象.分析了高功率光束小尺度自聚焦发生的过程中填充因子、调制度、对比度 及高阶对比度随B积分值的变化，指出高阶对比度在光束出现自聚焦成丝前后有更显著 的变化，所以是描述小尺度自聚焦效应的理想参数. 关键词： 小尺度自聚焦 三阶对比度 四阶对比度 功率谱密度相位噪声