铕对小麦根细胞钙调素及NAD激酶的影响研究

研究了Eu对小麦根细胞内钙调素的含量和活性以及对受钙调素调控的专一性酶NAD激酶的影响。结果表明，Eu^3＋有类似Ca^2＋的作用，影响受Ca^2＋浓度调控的信号系统关键蛋白——钙调素的活性和含量变化。从而引起钙调素调控酶NAD激酶的活性改变，最终影响细胞内生理生化过程。认为稀土离子对生物体的Hormesis效应町能与稀土离子对细胞信号传递系统的影响有关，稀土离子可能通过影响细胞信号系统来调节细胞内的各种生理生化变化，形成稀土元素生物效应的多样性特征。     

Potentiometric, luminescence and NMR study of the interaction of Eu with glyceryl phosphates

Complexation of europium(III) with glyceryl-1- and -2-phosphates has been studied by metal ion luminescence, ¹H and ¹³C NMR spectroscopy and potentiometry. From the luminescence and NMR studies, the formation of a 1:1 inner-sphere complex, in which the glyceryl phosphate is directly bound to the metal, is confirmed. Similar apparent binding constants at pH 2 were obtained by the three methods. Values obtained by NMR at pH 2 are 53 M⁻¹ and 12 M⁻¹ for glyceryl-1- and -2-phosphate, respectively. By comparison with literature data on related systems it is suggested that the ligands bind through the phosphate group. To obtain structural information from the NMR data, complexation has also been studied with the lanthanide ions Dy(III), Er(III) and Gd(III) using both chemical shift and relaxation data. From this, metal-proton distance ratios have been calculated. Comparison of ¹H and ¹³C NMR spectral data in the presence of paramagnetic lanthanides suggests conformational equilibria in the solutions. From the potentiometric studies, global formation constants have been determined, and speciation diagrams obtained over the pH range 1.5pH7.0 for ligand/metal ratios of 1 and 30. Implications of these results on lanthanide induced fusion of phospholipid membranes are discussed.     

Synthesis of Eu(III) and Tb(III) Complexes with Two New Amide Type Podands and Their Luminescence Properties

ＩｎｔｒｏｄｕｃｔｉｏｎＬａｎｔｈａｎｉｄｅｃｏｍｐｌｅｘｅｓｈａｖｅａｔｔｒａｃｔｅｄｍｕｃｈａｔｔｅｎｔｉｏｎｂｅｃａｕｓｅｏｆｔｈｅｉｒｉｍｐｏｒｔａｎｔａｐｐｌｉｃａｔｉｏｎｓ .1ＩｎｐａｒｔｉｃｕｌａｒＥｕ(ＩＩＩ)ａｎｄＴｂ(ＩＩＩ)ｃａｎｂｅｃｈａｒａｃｔｅｒｉｚｅｄｂｙｌｏｎｇ ｌｉｖｅｄ(ｍｓｔｉｍｅｓｃａｌｅ)ａｎｄｓｔｒｏｎｇｌｕｍｉｎｅｓｃｅｎｔｅｌｅｃｔｒｏｎｉｃａｌｌｙｅｘ ｃｉｔｅｄｓｔａｔｅｓ ,ｗｈｉｃｈｍａｋｅｓｔｈｅｍｉｍｐｏｒｔａｎｔｉｎａｎａｌｙｔｉｃａｌｃｈｅｍ…     

Crystal Structure and Luminescence of a Europium Coordination Polymer {[Eu(p-MOBA)_3·2H_2O]·0.5H_2O· 0.5(4,4′-bipy)}_∞

ＩｎｔｒｏｄｕｃｔｉｏｎＭｏｎｏｎｕｃｌｅａｒ ,ｄｉｎｕｃｌｅａｒａｎｄｐｏｌｙｍｅｒｉｃｔｙｐｅｓｏｆｃｒｙｓ ｔａｌｓｔｒｕｃｔｕｒｅｓｆｏｒｌａｎｔｈａｎｉｄｅｃｏｍｐｌｅｘｅｓｗｉｔｈｂｅｎｚｏｉｃａｃｉｄａｎｄｉｔｓｄｅｒｉｖａｔｉｖｅｓｈａｖｅｂｅｅｎｏｂｔａｉｎｅｄｂｅｃａｕｓｅｏｆｔｈｅｖａｒｉ ａｔｉｏｎｏｆｂｒｉｄｇｉｎｇｆｏｒｍｓｆｏｒｃａｒｂｏｘｙｌａｔｅｇｒｏｕｐａｎｄｃｏｏｒｄｉｎａ ｔｉｏｎａｂｉｌｉｔｙｏｆｄｉａｍｍｉｎｅｌｉｇａｎｄｓ ,ｓｕｃｈａｓ 1,10 ｐｈｅｎａ…     

Luminescence Properties of Terbium-, Cerium-, or Europium-Doped α-Sialon Materials

New interesting luminescent α-sialon (M_(m/val+)^val+ Si_12-(m+n) Al_(m+n)OnN_(16−n)) (M=Ca, Y) materials doped with Ce, Tb, or Eu have been prepared and their luminescence properties studied. These show that Tb and Ce are in the 3+ and Eu in the 2+ state. Low-energy 4f↔5d transitions are observed as compared to the luminescence of these ions doped in oxidic host-lattices. This is partially explained by the nitrogen-rich coordination of the rare-earth ion and partially by the narrow size of the lattice site. The latter gives rise to a strong crystal-field splitting of the 5d band and a rather large Stokes shift for Ce³⁺ and Eu²⁺ (6500-7500 and 7000-8000 cm⁻¹, respectively). For (Y,Tb)-α-sialon the Tb³⁺ 4f→5d excitation band (∼260 nm) is in the low-energy host-lattice absorption band (?290 nm), giving rise to a strong absorption for 254-nm excitation, but a low quantum efficiency. The latter is due to photoionization processes or selective excitation of Tb³⁺ at the defect-rich surface, resulting in radiationless transitions. Ce- and Eu-doped Ca-α-sialon show bright long-wavelength luminescence (maxima at 515-540 and 560-580 nm for Ce and Eu, respectively) with a high quantum efficiency and high absorption for 365- and 254-nm excitation. The Eu²⁺ emission intensity and absorption increases for increasing m, which is explained by the Eu²⁺ richer α-sialon composition. The position of the Eu^2α emission does not shift with changing composition of the host-lattice (m, n values), indicating that the local coordination of the Eu²⁺ ion is hardly dependent on the matrix composition.     

SrO—Al2O3—SiO2：Eu^3＋,Bi^3＋发光体的溶胶—凝胶法合成

制备无机固体材料大都采用高温固相反应,1971年Dislich报导了用溶胶-凝胶法制备多组份固体材料。近年来,有报导利用此法研制玻璃、玻璃陶瓷和陶瓷。我们在过去工作的基础上,合成了SrO-Al_2O_3-SiO_2:Eu~(3 ),Bi~(3 )发光体,研究了从凝胶至发光晶体的转变过程、Eu~(3 )和Bi~(3 )在SrO-Al_2O_3-SiO_2基质中的发光性质以及Bi~(3 )对 EU~(3 )的能量传递。     

镧系元素光化学 Ⅳ 铁和铈对光还原分离铕的影响

本文在水溶液中以1:1HCOOH～HCOONa做自由基清除剂,Na_2SO_4做光还原产物Eu~(2+)沉淀剂,研究了杂质铁和含量变化对光还原分离铕的影响,并用紫外光谱证明了体系中是光反应生成的Fe和Ce~(4+)对发生氧化,致使Eu~(2+)光还原生成Eu~(2+)速度减慢,铕的收率下降。     

Crystal Structure of Complex Tris（4,4,4—trifluoro—1—pheny1—1,3—butanedione）（1,10—phenanthroline）Europium（Ⅲ）

The complex Eu(btfa)₃ (phen) (btfa=4,4,4‐trifluoro‐1‐phenyl‐1, 3‐butanedione, phen = 1,10‐phenanthroline) has been prepared and characterized by elemental analysis, IR and UV spectroscopies. The crystal and molecular structures of the complex have been determined by X‐ray diffraction analysis. It belongs to the monoclinic crystal system, space group P2₁/c with a = 0.9700(2) nm, b = 3.7450(5) nm, c = 1.0917(3) nm, β = 92.51(2)°, V = 3.962(1) nm⁵, Z = 4, D_c = 1.639 g/cm³, μ = 1.676 mm^?1, F(000) = 1936, R₁, = 0.0388, wR₂ = 0.0775. Structure analysis shows that the europium(III) ion is coordinated to six oxygen atoms of β‐diketonate anions and two nitrogen atoms of phenanthroline molecule. The coordination polyhedron is an approximate square antiprism.     

2-噻吩乙醛酸-三苯基氧化膦-铕配合物的合成、结构表征及荧光性能的研究

用硝酸铕、2-噻吩乙醛酸(HL)和三苯基氧化膦(TPPO)合成了一种新型固体发光配合物;用元素分析、电导率、红外光谱和核磁共振确定了该配合物的分子式为EuL3TPPPO((H2O)2;在室温下测定了该配合物的荧光激发光谱和发射光谱;配合物中Eu(Ⅲ)离子的3个主要跃迁5D0→7F1,5D0→7F2和5D0→7F4分别位于593.4,618.8和699.4 nm.该固体配合物于室温下被紫外灯照射可以发出很强的红色荧光.IR光谱中2-噻吩乙醛酸在与稀土铕离子形成配合物后,vas(-COO-)由钠盐的1632 cm-1移至1612 cm-1,vs(-COO-)由1389 cm-1移至1409cm-1;vc=o(α-酮基)由HL的1654 cm-1移至1662 cm-1.配合物的vEu-o吸收峰出现在541 cm-1.在1HNMR谱图中,噻吩环上的3个氢原子的化学位移在形成配合物后移向高场;三苯基氧化膦中苯环上5种不同环境的质子的化学位移在形成配合物后向低场移动.TG分析证明,该固态配合物于空气中在常温至190℃以内是稳定的.     

含稀土铕(Ⅲ)配位聚合物的研究

将铕的有机配合物NaEu(TTA)4与聚（苯乙烯-丙烯酸）（PSAA）反应制备了铕配位聚合物[Eu(Ⅲ）-TTA-PSAA]，用电导、DTA-TGA、荧光光谱等对其进行了表征。由于配合物中存在着Eu^3 分别与TTA^-和PSAA分子中羧基的配位作用，并进一步交联，因此配合物样品均不溶于大部分有机溶剂，只能溶于N，N-二甲基甲酰胺和丙三醇/异丙醇的混合溶剂，且耐热性得到提高。配合物为褐色固体，在常温、紫外光下发出红光，主要是由于Eu^3 离子的^5D0→^7F2跃进。讨论了pH值对配合物荧光强度的影响，当pH=10时，合成的配合物具有最好的荧光性。