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本文研究了铽(Tb)、钇(Y)、钆(Gd)及它们的混合物对铕(Eu)-噻吩甲酰三氟丙酮(TTA)-氯化甲基三烷基铵(N_(263))-Triton X-100体系的共发光效应,发现稀土离子混合物的共发光效应具有线性加和性,用混合共发光体系不仅能保持单个稀土离子的共发光体系的增敏性,而且抗干扰能力增强,并经过实际样品分析的验证,结果令人满意。 相似文献
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稀土混合共发光效应的研究—(铽—钆—钇)—铕—噻吩甲酰三氟丙酮—氯化… 总被引:1,自引:1,他引:1
本文研究了铽(Tb)、钇(Y)、钆(Gd)及它们的混合物对铕(Eu)-噻吩甲酰三氟丙酮(TTA)-氯化甲基三烷基铵(N263)-Triton X-100体系的共发光效应,发现稀土离子混合物的共发光效应具有线性加和性,用混合共发光体系不仅能保持单个稀土离子的共发光体系的增敏性,并经过实际樯品分析的验证,结果令人满意。 相似文献
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用荧光光谱法研究了美他环素(MTC)与β-环糊精(β-CD)形成包合物的荧光光谱特性. 对美他环素与β-环糊精形成包合物的条件、作用机理进行了研究, 探讨了可能的包合方式, 测定了包合物的包合常数和热力学参数ΔH、ΔS和ΔG, 验证了包合反应驱动力. 实验结果表明: MTC与β-CD可形成1∶1的包合物, 包合物的包合常数为382.19 mol/L. 包合过程中, ΔH=-99.10 kJ/moL, ΔS=-286.42JmoL-1K-1, 常温下ΔG<0. 说明包合反应为自发反应, 且是一个焓驱动过程. 在Tris-HCl缓冲溶液中, β-CD的加入生成包结物可显著增强美他环素的荧光强度, 据此建立了测定药物制剂中美他环素的新方法. 该方法的定量线性范围为1.93×10-7~1.45×10-5 mol/L, 检出限为1.45×10-8 mol/L,相对标准偏差为1.2% (n=13). 对药物制剂中美他环素的含量进行了测定, 测定结果与标示量吻合, 平均回收率为102%. 相似文献
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It is found that the fluorescence of Tb-adenosine triphosphate (ATP)-phenanthroline (phen) system can be enhanced by Gd3+. The fluorescence enhancement of the Tb-Gd-ATP-phen system is considered to originate from intramolecular and intermolecular energy transfers, and the energy-insulating sheath effect of Gd-ATP-phen complex. In addition, a new energy transfer pathway in Tb-ATP-phen system is proposed. As a mediator, phen can transfer the energy absorbed by ATP to Tb3+ through the stacking action between aromatic ring of phen and purine ring of ATP. The proposed method has been used to determine trace amount of ATP. The detection limit is 5.4 × 10−9 mol/l, which is about 40 times lower than that of the Tb-ATP-phen system. The proposed method is one of the most sensitive fluoremetries of ATP. 相似文献
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The Reactions of Europium and Yttrium with N‐Iodinetriphenylphosphoraneimine. Crystal Structures of [EuI2(DME)3], [Eu2I(NPPh3)5(DME)] and [Y2I(NPPh3)4(THF)4]+I3– When treated with ultrasound, the reaction of europium metal with INPPh3 in 1,2‐dimethoxyethane (DME) leads to the complexes [EuI2(DME)3] ( 1 ) and [Eu2I(NPPh3)5(DME)] ( 2 ) which are separated from each other by fractional crystallization. On the other hand, the reaction of yttrium metal with INPPh3 under similar conditions in THF gives the ionic phosphoraneiminato complex [Y2I(NPPh3)4(THF)4]+I3– ( 3 ). All complexes are characterized by crystal structure determinations. 1 : Space group P21, Z = 2, lattice dimensions at 188 K: a = 848.9(1); b = 1059.4(1); c = 1227.9(1) pm; β = 93.793(6)°; R = 0.0246. In the molecular structure of 1 the europium atom is eightfold coordinated with a bond angle I–Eu–I of 158.51°. 2 · 2 DME: Space group P1, Z = 2, lattice dimensions at 193 K: a = 1405.5(1); b = 1652.2(2); c = 2203.7(2) pm; α = 89.404(11)°; β = 72.958(11)°; γ = 78.657(11)°; R = 0.0391. In 2 the europium atoms are linked by the μ‐N‐atoms of two (NPPh3–) groups to form a planar Eu2N2 four‐membered ring. One of the Eu atoms is terminally coordinated by the N atoms of two (NPPh3–) groups, thus achieving a distorted tetrahedral surrounding. The second Eu atom is coordinated by the N atom of one (NPPh3–) group, by the terminally bounded iodine atom and by the oxygen atoms of the DME chelate, thus achieving a distorted octahedral surrounding. 3 · 61/2 THF: Space group P1, Z = 2, lattice dimensions at 103 K: a = 1739.7(2); b = 1770.1(2); c = 2153.8(3) pm; α = 74.929(15)°; β = 84.223(14)°; γ = 64.612(12)°; R = 0.0638. In the cation [Y2I(NPPh3)4(THF)4]+ of 3 the yttrium atoms are linked by the μ‐N atoms of two (NPPh3–) groups as well as by the μ‐I atom. One (NPPh3–) ligand and two THF molecules complete the distorted octahedral coordination at each yttrium atom. 相似文献
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《Analytical letters》2012,45(6):1183-1191
Abstract A study of the enhancement effect on the fluorescence intensity of the Eu3+–-thenoyltrifluoroacetone (TTA)–-cetyltri–-methylammonium bromide (CTMAB) and the Dy3+ pyrocatechol–-3,5-disulphonic acid (Tiron) systems by Y3+has been carried out. In the presence of yttrium the fluorescence intensity of the systems was enhanced by a factor of about 100 and 15, respectively. The fluorescence intensity was a linear function of the concentration of europium or dysprosium in the range 1.0 × 10?10–-1.0 × 10?8mol dm?3 and 8.0 × 10?8–-9.0 × 10?6mol dm?3, respectively. The detection limit was 1.0 × 10?11mol dm?3 and 1.0 × 10?10mol dm?3, respectively. The standard addition method was used for the determination of europium or dysprosium in rare earth oxides and gave satisfactory results. The mechanism of enhanced fluorescence was proposed. 相似文献
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钇离子及其阳离子卟啉配合物与金黄色葡萄球菌的相互作用 总被引:14,自引:0,他引:14
用LKB-2277生物活性检测系统考察了Y~(3+),TMP及其阳离子型钇卟啉配合物 {[Y(TMP)(H_2O)_3]Cl, TMP = 5, 10, 15, 20-四(4-甲氧基苯基)卟啉}对金黄色 葡萄球菌全程代谢作用的影响,测定了Y~(3+),TMP和[Y(TMP)(H_2O)_3]Cl对金黄 色葡萄球菌作用的产热曲线,根据产热曲线求算了金黄色葡萄球菌在Y~(3+),TMP ,[Y(TMP)(H_2O)_3]Cl作用下生长代谢的速率常数k_1,k_2,抑制率I_1,I_2,和 半抑制浓度IC_(50)~1,IC_(50)~2等热动力学参数。实验结果表明:Y~(3+),[Y (TMP)(H_2O)_3]Cl对金黄色葡萄球菌的生长代谢有双向调节作用,在低浓度下表现 为刺激作用,高浓度为抑制作用,而TMP对金黄色葡萄球菌的生长代谢主要为抑制 作用,在低浓度下表现为刺激作用,高浓度为抑制作用,而TMP对金黄色葡萄球菌 的生长代谢主要为抑制作用,对金黄色葡萄球菌的抑制作用[Y(TMP)(H_2O)_3]Cl > TMP > Y~(3+)。 相似文献
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钇(Ⅲ)、铽(Ⅲ)、铒(Ⅲ)对氨基苯甲酸配合物共掺杂二氧化硅的光声光谱研究 总被引:1,自引:0,他引:1
合成了Tb(p-ABA)3·H2O和Ln(p-ABA)3·H2O(p-ABA: 对氨基苯甲酸, Ln: Y或Er)配合物共掺杂的SiO2样品. 荧光光谱测定结果表明, Y(p-ABA)3·H2O的引入增强了样品中Tb3+离子的特征发光, 而Er(p-ABA)3·H2O的引入使Tb3+的发光减弱. 光声光谱结果表明, 与Tb3+配合物单掺的样品相比, Tb3+和Y3+配合物共掺样品的光声强度降低; 而Tb3+和Er3+配合物共掺的样品则情况相反. 实验测定了共掺杂样品的相对量子发光效率和发光寿命, 从无辐射跃迁和辐射跃迁的角度提出共发光效应可能的机制. 结合对室温下陈化干燥样品的分析发现, 只有经适当的热处理过程才能在SiO2凝胶中形成具有多核结构的稀土配合物. 相似文献
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利用Bridgman-Stockbarger方法在氩气气氛下生长出KZnF3:Eu^3+单晶,测定了晶体的激发光谱、荧光发射光谱和ESR谱,讨论了Eu离子的取代格位。 相似文献
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The compounds Eu(OH)(CrO4) and Y(OH)(CrO4) were obtained under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction analysis. They are isostructural and crystallize in the monoclinic system, space group P21/n (no. 14) with lattice parameters a = 8.278(1) Å, b = 11.400(2) Å, c = 8.393(1) Å, β = 93.76(2)°, V = 790.3(2) Å3, Z = 4, d = 4.79 g · cm–3 for Eu(OH)(CrO4) and a = 8.151(1) Å, b = 11.362(2) Å, c = 8.285(1) Å, β = 94.23(1)°, V = 765.2(2) Å3, Z = 4, d = 3.85 g · cm–3 for Y(OH)(CrO4). The [EuO8] polyhedra form infinite double chains along the a direction, which are connected by common edges and corners. These double chains are related together in the two other directions by the [CrO4]2– tetrahedra to form a three‐dimensional network in which channels appear parallel to the [100] direction. We examine the structural evolution, as a function of the Ln3+ ionic radius, in the series Ln(OH)(CrO4) compounds (with Ln = Nd, Eu, Gd, Tb, Er, Yb) and Y(OH)(CrO4). To determine the best coordination number of each lanthanide and yttrium ions, different calculations of bond valence sum were realized. 相似文献
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J.L. Ferrari M.A. Cebim M.A. Couto dos Santos 《Journal of solid state chemistry》2010,183(9):2110-2115
Y2O3:Eu3+ (5 mol% Eu3+) and Y2O3:Eu3+ (5 mol% Eu3+) containing 1 mol% of Ag nanoparticles were prepared by heat treatment of a viscous resin obtained via citrate precursor. TEM and EDS analyses showed that Y2O3:Eu3+ (5 mol% Eu3+) is formed by nanoparticles with an average size of 12 nm, which increases to 30 nm when Ag is present because the effect of metal induced crystallization occurs. Ag nanoparticles with a size of 9 nm dispersed in Y2O3:Eu3+ (5 mol% Eu3+) were obtained and the surface plasmon effect on Ag nanoparticles was observed. The emission around 612 nm assigned to the Eu3+ (5D0→7F2) transition enhanced when the Ag nanoparticles were present in the Y2O3:Eu3+ luminescent material. 相似文献
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用溶胶-凝胶法合成无机玻璃、玻璃陶瓷和陶瓷已得到发展。本文报道利用此法低温合成(Ca-Zn)O-Al_2O_3-SiO_2:Eu~(3+),Bi~(3+)发光体的研究结果。所用原料为99.99%的Eu_2O_3、99.99%的金属铝、99.999%的金属铋及CaCO_3、ZnCO_3和Li_2CO_3(提纯)。上述原料用HNO_3(GR)溶解。将计算的摩尔比量的Si(OC_2H_5)_4、C_2H_5OH和CH_3COOH以及Ca(NO_3)_2、Al(NO_3)_3、Zn(NO_3)_2、LiNO_3、Bi(NO_3)_3和Eu(NO_3)_3溶液,在一定的pH值下,在75℃水浴中回流数小时,经水解,缩聚成凝胶。制得 相似文献