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1.
采用液相色谱流动相为0.05mol·L~(-1)草酸和0.095mol·L~(-1)氢氧化锂,流速为1.0ml·min~(-1);柱后衍生试剂为0.001mol·L~(-1)PAR+0.3mol·L~(-1)氨水+0.1mol·L~(-1)乙酸,流速为1.0ml·min~(-1),进样体积为20μl,检测波长为500nm,同时对Pb~(2+)、Cu~(2+)、Cd~(2+)、Co~(2+)、Zn~(2+)和Ni~(2+)检测。方法可用于水样检测。  相似文献   

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Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail. A cooperative vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2, 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.  相似文献   

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A series of Ln(Ⅲ) dipivaloylmethanates Ln(dpm)3 has been obtained. The crystal structures of Tm(dpm)3(1) and Yb(dpm)3(2) were determined by X-ray analysis at 200(2) K(Pmn21, Z = 2; a = 17.7509(8), b = 10.5805(4), с = 9.8380(4) ?, V = 1847.7(1) ?3 for(1) and a = 17.7272(6), b = 10.5882(3), с = 9.8440(3) ?, V = 1847.7(1) ?3 for(2)). These data complete the structural evaluation of lanthanoid tris-dipivaloylmethanates. Compounds 1 and 2 are isostructural to the complexes Ln(dpm)3(Ln = Er and Lu). It is demonstrated that the volatility of trisdipivaloylmethanates of rare earth elements increases from the complex of Lu to that of La.  相似文献   

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(N2H5)2GeF6 and (N2H6)2(GeF6)F2 have been prepared by reactions of N2H4·H2O and N2H6F2 with fluorogermanic acid. The solids have been characterized by chemical analysis and vibrational spectra. X-ray diffraction study has shown that crystals of (N2H5)2GeF6 are monoclinic, space group P 21/n, with unit-cell dimensions a = 6.015 (2), b = 5.249 (1), c = 11.181 (2) Å, β = 100.15 (2)o, and Z = 2. There are N2H5+ cations and GeF62? anions in the crystals interconnected by hydrogen bonds of the type NH····F and NH····N.  相似文献   

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Hopîrtean E  Liteanu C  Vlad R 《Talanta》1975,22(10-11):912-913
The paper reports the results obtained in the complexometric determination of Bi(3+), Fe(3+) and Cr(3+) by using an Hg(2+)-sensitive membrane-electrode for the end-point indication. The determination of Bi(3+) and Fe(3+) is performed after addition of mercuric complexonate from which these cations release Hg(2+) by means of which the electrode senses the equivalence point. In the case of Cr(3+) an excess of complexone is added and the surplus is titrated with a standard solution of Hg(2+) in the presence of the Hg(2+)-sensitive membrane-electrode.  相似文献   

8.
离子色谱法测定水中钙和镁   总被引:7,自引:0,他引:7  
水的硬度测定,通常采用EDTA滴定法,文中改用离子色谱法测定,一次进样后同时测定水样中mg.L^-1级的钙和镁,然后换算成以mg.L^-1,硕酸钙表示的硬度,方法的回民率在98.2-102.0%之间,相对标准偏差为0.94%-1.21%,具有简便,快速,准确的特点。  相似文献   

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采用溶胶-凝胶法制备了Yb3+和Er3+掺杂的GdAlO3荧光粉体.XRD结果表明样品为正交晶系结构.研究了不同波长激发下的室温发射光谱以及上转换发光光谱.结果表明样品在1550 nm处有很强的荧光发射,并且在样品中存在显著的Yb3+到Er3+之间的能量传递过程.980 nm红外光激发下的上转换发光光谱表明样品有绿色和...  相似文献   

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利用Hg2+与DNA中胸腺嘧啶(T)结合的高度特异性和纳米金在石英晶体微天平(QCM)上的信号放大作用,设计了一种简便灵敏的Hg2+检测方法.纳米金采用柠檬酸钠还原法制备,其表面用末端带巯基的寡核苷酸探针进行自组装修饰,并用6-巯基己-1-醇(MCH)部分取代表面探针,以减少杂交空间位阻.结果表明,寡核苷酸链长为9bp、T个数为7的序列具有较高灵敏度;线性范围为5.0~100 nmol/L;检出限为2.0 nmol/L;Ca2+、Mg2+等其它金属离子无明显干扰.用于环境水样中Hg2+的测定, RSD<2.9%;加标回收率为97.3%~101.2%  相似文献   

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BaFCl:Ce^3+和BaFCl:Gd^3+晶体中的发光中心   总被引:1,自引:0,他引:1  
运用不同的固相反应条件制备或后处理了几种BaFCl:RE~(3+)(RE=Ce或Gd)晶体,测定了它们的荧光光谱,对照并分析光谱数据和不同条件下可能引入晶体缺陷的情况,推论出晶体中存在有2类发光中心,即由RE_(?)-F_(?)和RE_(?)-F_(?)缔合体构成的中心。  相似文献   

14.
A series of pyrazole and triazole based dinucleating ligands have been synthesized and their complexation potential for metal ions, which exhibit square planar coordination geometry has been studied. In the case of Cu(2+) the complexation equilibria in solution have been determined using pH titrations. Species with 1 : 1 stoichiometry [CuLH(n)], 2 : 1 stoichiometry [Cu(2)LH(m)], and of dimeric nature [Cu(2)L(2)H(p)], have been detected and their overall stability constants have been measured. The reactivity of the dinuclear species [Cu(2)LH(-1)] towards phosphate ester hydrolysis have shown that the OH-functionality incorporated in some of the ligands does not enhance the hydrolysis rate. Several ligands were reacted with Pt(2+) to give insoluble dinuclear species [Pt(2)LI(3)]. One of them was studied by X-ray diffraction and shows that the two Pt(2+) are bridged by the pyrazolide group and by one I(-). The remaining two positions are occupied by the amino group in alpha position of the heterocyclic ring and a terminal I(-). The nearly planar [Pt(2)LI(3)] units form sheets in the crystals, which are about 4 A apart and thus indicate pi stacking interactions.  相似文献   

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钇-铕-美他环素-CTMAB稀土共发光体系的研究及分析应用   总被引:1,自引:0,他引:1  
利用荧光光谱法研究了钇-铕-美他环素(MTC)-CTMAB体系的稀土共发光效应,最佳形成条件,并对其作用机理进行了探讨,提出了测定MTC的荧光分光光度法。结果表明,共发光体系的荧光强度与MTC的浓度在1.0×10-7mol/L~1.5×10-5mol/L范围内呈良好的线性关系,其检出限为3.6×10-8mol/L。采用标准加入法测定了药物制剂中的MTC。  相似文献   

16.
用主温固相法合成了Yb3+、Bi3+共掺的YVO4,研究了Bi3+的掺入对YVO4:Yb3+发光光谱的影响和近红外发光的敏化作用.X射线衍射图谱研究表明:掺入Yb3+、Bi3+之后,基质YVO4的晶格结构没有发生明显变化.Bi3+的掺入不仅显著增强了样品中Yb3+的特征远红外发光强度,还使YVO4:Yb3+激发光谱的范围红移,当Bi3+掺入的摩尔分数从0增加到0.05时,样品的最强激发峰位置从335nm红移至352 nm,激发光谱范围由300-360 nm扩宽至300-430 nm.优化的Bi3+掺入量为0.03.初步讨论了VO43-,Bi3+Yb3+间的能量传递机理.结果表明Bi3-的共掺使YVO4:Yb3+样品对长波紫外光的响应性能大大改善,作为一种基于量子剪裁的光谱转换材料,可以更好地匹配太阳光的能量谱,有助于提高硅太阳能电池的光电转换效率.  相似文献   

17.
We report efficient white upconversion luminescence in Yb(3+)-, Er(3+)- and Tm(3+)-doped monophasic and biphasic Y(2)BaZnO(5) phosphors under 977 nm near-infrared excitation and at low excitation power densities (down to ~25 mW mm(-2)).  相似文献   

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根据流动注射-化学发光的通用实验装置图,设计并通过标准光刻技术,湿化 学刻蚀及热键合技术制作了玻璃微芯片。在该芯片上将毛细管电泳分离与化学发光 检测相联用,鲁米诺和H_2O_2化学发光反应溶液通过实验室自制的微流泵输送。对 所用电压,缓冲溶液和发光试剂流速等实验条件进行了优化。在所选的最佳条件下 ,成功地实现了金属离子Cu~(2+),Co~(2+),Ni~(2+)的电泳分离-化学发光检测, 过渡金属离子。  相似文献   

20.
Cerium and europium codoped yttrium aluminum garnet(YAG:Ce,Eu) nanophosphors were prepared by sol-gel method.We systematically explored the structure,composition,morphology and photoluminescence(PL) properties by using X-ray diffraction,scanning electron microscope,high resolution transmission electron microscope,energy dispersive spectrometer,photoluminescence emission and excitation spectra techniques,and focused on clarifying the change of local structure surrounding Ce~(3+) ions by utilizing advanced quantitative ~(27)Al magic angle spinning nuclear magnetic resonance spectroscopy.The results show that the lattice constant slightly increases as the Ce~(3+) and Eu~(3+) ions incorporate,and the geometric distortion of local structure surrounding Ce~(3+) activator introduced by the incorporated Eu~(3+) coactivator causes the variation of crystal field,which results in red shift of Ce~(3+) PL emitting in YAG:Ce,Eu nanophosphor.Furthermore,the YAG:Ce,Eu nanophosphors could exhibit several sharp and narrow ~5D_0 → ~7F_J(J = 1~4) emissions of Eu~(3+) ion besides the classic broad ~5d_1 → ~4f(~2F_(5/2),~2F_(7/2)) emissions of Ce~(3+) ion under near ultraviolet(UV) excitation.  相似文献   

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