掺铒联吡啶钌为探针分子压敏漆的制备及氧猝灭特性

以2,2′-联吡啶,三氯化钌(RuCl3),氯化铒(ErCl3)为原料合成了铒掺杂的探针分子。将探针分子加入到铕掺杂的硅溶胶基质中获得了铕、铒共掺杂的压敏漆样品。采用IR,SEM,EDS及荧光发射光谱对探针分子和压敏漆进行了表征。红外光谱结果表明,探针分子中联吡啶的结构没有被破坏。扫描电镜观察发现探针分子呈片状,EDS测试发现探针分子表面含有Er,Ru等元素。紫外吸收光谱表明压敏漆的最佳吸收波段位于200~500 nm处,选择410 nm作为激发光源,压敏漆在590 nm处有很强的荧光发射,并且随着空气压力的增大(即氧分子浓度的增加),压敏漆的荧光发射强度降低,说明压敏漆具有较好的氧猝灭特性。     

不同稀土掺杂温敏漆的制备及性能研究

以RuCl3,联吡啶为原料,并在其中分别加入氯化铒、氯化钕和氯化钆,制备了铒掺杂、钕掺杂及钆掺杂联吡啶钌探针分子,将三种探针分子分别加入到MMA中,在引发剂引发下进行聚合,获得三种稀土掺杂的温敏漆样品.对探针分子及温敏漆进行了红外光谱、紫外吸收和荧光光谱测试.红外光谱测试结果表明,探针分子中联吡啶钌的结构没有被破坏.紫外吸收光谱表明温敏漆的最佳吸收波段位于200～550 nm范围内.选择410 nm作为激发光源,发现三种温敏漆在610 nm左右有很强的荧光发射峰,并且随着温度的升高,三种温敏漆的荧光强度均减弱,说明具有良好的温度猝灭特性,其中钆掺杂温敏漆灵敏度最强.     

Eu0.5La0.5（TTA）3/PMMA温敏漆的制备及性能研究

以氯化铕、氯化镧、噻吩甲酰基三氟丙酮(TTA)为原料合成了Eu0.5La0.5(TTA)3探针分子,将探针分子与甲基丙烯酸甲酯(MMA)混合后聚合,获得Eu0.5La0.5(TTA)3/PMMA温敏漆。采用红外光谱、扫描电镜、紫外吸收光谱及荧光光谱对探针分子及温敏漆性能进行了表征。红外光谱表明,Eu(La)与TTA形成配位键,且镧的掺入并未改变Eu(TTA)3结构;SEM照片显示探针分子为片状晶体;紫外吸收光谱表明,探针分子的最佳吸收波段位于226～381 nm处。340 nm激发下,发现温敏漆在613 nm处具有最强荧光发射峰,且镧的掺杂对Eu(TTA)3发光存在增益作用;不同温度下荧光光谱表明,随着温度的升高,温敏漆荧光发射强度逐渐减弱,说明温敏漆具有良好的温度猝灭特性。     

稀土钇掺杂Eu(TTA)3/PMMA温敏漆的制备及性能分析

本文以氯化铕、氯化钇、噻吩甲酰基三氟丙酮(TTA)为原料合成了钇掺杂Eu(TTA)3探针分子。将探针分子掺杂到聚甲基丙烯酸甲酯(PMMA)基质中,获得稀土钇掺杂Eu(TTA)3/PMMA温敏漆。采用IR、紫外吸收光谱和激发发射光谱对探针分子结构及温敏漆荧光特性进行了表征。红外光谱表明,稀土Eu(Y)与TTA形成配位键,且钇的掺入未改变Eu(TTA)3结构。紫外吸收光谱表明,探针分子的最佳吸收波段位于290~376 nm处。激发发射光谱表明,在340 nm激发下,温敏漆在614 nm处有最强发射峰,且钇对Eu(TTA)3发光具有增益作用,当钇含量为50%时,增益作用最强。不同温度下发射光谱表明,随着温度的升高,温敏漆的荧光发射强度逐渐减弱,说明温敏漆具有良好的温度猝灭特性,且掺入钇后温敏漆的测温灵敏度有所提高。     

以Eu(DBM)3Bipy为荧光探针的温敏漆的制备及性能表征

利用氯化铕(EuCl_3)、二苯甲酰甲烷(DBM)和联吡啶(Bipy)为原料合成了Eu(DBM)_3Bipy探针分子,并将探针分子掺入到甲基丙烯酸甲酯(MMA)中,在过氧化苯甲酰(BPO)引发剂的作用下聚合,获得温敏漆Eu(DBM)_3Bipy/PMMA。采用红外光谱仪、紫外吸收光谱仪、扫描电子显微镜和荧光光谱仪对探针分子的结构、形貌、发光性能和温敏漆的温度猝灭性能进行了表征。红外及紫外吸收光谱分析发现稀土离子Eu3+与配体配位成键,成功合成Eu(DBM)_3Bipy探针分子;扫描电镜及能谱分析表明Eu(DBM)_3Bipy探针分子呈碎片状,大小约为150 nm,且主要由C、N、O和Eu四种元素组成;荧光光谱表明,在367 nm激发下,Eu(DBM)_3Bipy探针分子的最佳发射波长位于612 nm,且第二配体Bipy对Eu(DBM)_3的荧光发射具有增益作用。在不同温度下测试温敏漆的荧光发射特性,发现温敏漆Eu(DBM)_3Bipy/PMMA在40~90℃温度区间内具有良好的荧光温度猝灭特性,测温灵敏度最高的温度区间位于40~60℃。     

以Eu(DBM)3Bipy为荧光探针的温敏漆的制备及性能表征

利用氯化铕（EuCl₃）、二苯甲酰甲烷（DBM）和联吡啶（Bipy）为原料合成了Eu（DBM）₃Bipy探针分子,并将探针分子掺入到甲基丙烯酸甲酯（MMA）中,在过氧化苯甲酰（BPO）引发剂的作用下聚合,获得温敏漆Eu（DBM）₃Bipy/PMMA。采用红外光谱仪、紫外吸收光谱仪、扫描电子显微镜和荧光光谱仪对探针分子的结构、形貌、发光性能和温敏漆的温度猝灭性能进行了表征。红外及紫外吸收光谱分析发现稀土离子Eu³⁺与配体配位成键,成功合成Eu（DBM）₃Bipy探针分子;扫描电镜及能谱分析表明Eu（DBM）₃ Bipy探针分子呈碎片状,大小约为150 nm,且主要由C、N、O和Eu四种元素组成;荧光光谱表明,在367 nm激发下,Eu（DBM）₃ Bipy探针分子的最佳发射波长位于612 nm,且第二配体Bipy对Eu（DBM）₃的荧光发射具有增益作用。在不同温度下测试温敏漆的荧光发射特性,发现温敏漆Eu（DBM）₃Bipy/PMMA在40~90℃温度区间内具有良好的荧光温度猝灭特性,测温灵敏度最高的温度区间位于40~60℃。     

含均二苯乙烯荧光探针的合成及其对金属离子的识别研究

通过Wittig-Horner反应合成了两个含有均二苯乙烯发色团, 一端为N,N-双(2-乙酰氧乙基)氨基受体, 另一端分别为N,N-二甲氨基(DMDE)或N,N-二苯氨基(DPDE)的荧光探针分子. 进行了NMR和MS表征. 测试了加入不同金属离子时探针分子的吸收和荧光光谱变化. 加入Ag+和Zn2+, DMDE在420 nm处出现强的荧光峰, 在600 nm的荧光峰先增强后减弱, 认为发生了分子间的荧光共振能量转移. 而DPDE在加入Ag+和Zn2+, 420 nm处无荧光发射, 600 nm处的荧光红移并减弱.     

镱铒共掺硅酸盐玻璃三波段光致发光特性数值分析

考虑两级合作上转换、激发态吸收、交叉弛豫等非线性效应,建立了镱铒共掺硅酸盐玻璃材料9个能级的11个速率方程。唯象地构造了合作上转换系数随镱铒掺杂浓度的变化函数,数值模拟了镱铒共掺硅酸盐玻璃1530,664,549nm 3个波段的光致发光强度与掺杂浓度、抽运功率的变化关系。计算结果表明：掺铒浓度一定,镱浓度增加时,对于1530nm荧光而言,有最佳的掺镱浓度,但红光和绿光荧光强度随掺镱浓度始终增强;保持镱铒掺杂浓度不变,抽运功率增加时,3种荧光强度均单调增强,差别在于增幅速率不同,且近红外光强有饱和趋势。计算结果与实验测量相吻合。     

稀土(Gd3+,La3+)对Eu(p-MOBA)3phen/PMMA荧光及温敏特性的影响

以稀土氧化物(Eu_2O_3,Gd_2O_3,La_2O_3)、对甲氧基苯甲酸(p-MOBA)、菲咯啉(phen)为原料制备了不同稀土离子(Gd~(3+),La~(3+))掺杂的Eu(p-MOBA)_3phen探针分子。将所合成的探针分子与甲基丙烯酸甲酯(MMA)混合,以过氧化苯甲酰(BPO)为引发剂引发聚合,制得不同稀土(Gd~(3+),La~(3+))掺杂的Eu(p-MOBA)_3phen/PMMA温敏漆样品。利用扫描电镜、紫外-可见吸收光谱、红外光谱和荧光光谱对探针分子的形貌、结构、发光性能及温敏漆的荧光温度猝灭特性进行表征。红外光谱、紫外可见吸收光谱及扫描电镜能谱分析表明,Eu~(3+)与配体p-MOBA、phen成功配位,且掺入的稀土离子(Gd~(3+),La~(3+))未改变Eu(p-MOBA)_3phen结构,说明掺入的稀土离子(Gd~(3+),La~(3+))部分取代了Eu~(3+)。荧光光谱表明,稀土离子(Gd~(3+),La~(3+))的掺入对Eu(p-MOBA)_3phen的发光均具有增益作用,并且相应的温敏漆在50～100℃温度范围内都具有良好的荧光温度猝灭特性。而且相比于镧掺杂的Eu(p-MOBA)_3phen/PMMA,钆掺杂的Eu(p-MOBA)_3phen/PMMA具有更强的荧光发射和更高的测温灵敏度。可见,不同的稀土(Gd~(3+),La~(3+))对Eu(p-MOBA)_3phen/PMMA的荧光及温敏特性影响是不同的。     

([Ru(bpy)_3]~(2+)-Eu(TTA)_3Phen)/PMMA温敏漆的制备及性能研究

合成了[Ru(bpy)3]2+和Eu(TTA)3Phen两种探针分子,并将两者与甲基丙烯酸甲酯(MMA)混合,在引发剂BPO作用下进行聚合,获得具有温度响应性能的([Ru(bpy)3]2+-Eu(TTA)3Phen)/PMMA温敏漆。采用IR、紫外吸收光谱和荧光光谱对探针分子的结构及温敏漆的荧光特性进行了表征。红外光谱和紫外吸收光谱表明:Ru与2,2'-联吡啶分子通过双氮配位,有O→Eu配位键形成。荧光光谱表明:温敏漆样品的温度猝灭性能较好,并且在不同温度范围内测温灵敏度不同,由452 nm激发时,温敏漆样品在25~45℃范围内测温灵敏度高,最强的荧光发射峰位于584 nm;由342 nm激发时,在45~65℃范围内测温灵敏度高,最强的荧光发射峰位于612 nm。     

Complexes of lanthanum,gadolinium, and erbium iodides with acetamide: Synthesis and structure

New acetamide complexes of lanthanum, gadolinium, and erbium iodides of the composition LnI₃ · 4AA · 4H₂ O (Ln = La, Gd, Er; AA = CH₃CONH₂) are synthesized and studied. The synthesized complexes are characterized by the data of chemical analysis and IR spectroscopy and are studied by X-ray diffraction analysis. The coordination of the ligands (water and acetamide molecules) by the lanthanum, gadolinium, or erbium atom occurs through the oxygen atoms. The coordination polyhedron of the Ln atom is a distorted square antiprism. The iodide ions are not coordinated and exist in the external sphere.     

Synthesis，Crystal Structure and Infrared Spectrum of Lanthanum Dinuclear Coordination Compound with Alanine：〔La_2（ala）_4（H_2O）_8〕·（ClO_4）_6

Ｓｙｎｔｈｅｓｉｓ，ＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅａｎｄＩｎｆｒａｒｅｄＳｐｅｃｔｒｕｍｏｆＬａｎｔｈａｎｕｍＤｉｎｕｃｌｅａｒＣｏｏｒｄｉｎａｔｉｏｎＣｏｍｐｏｕｎｄｗｉｔｈＡｌａｎｉｎｅ：〔Ｌａ_２（ａｌａ）_４（Ｈ_２Ｏ）_８〕·（ＣｌＯ_４）_６...     

Thermal investigations of dehydration of lanthanide(iii) 5-nitroanthranilates

The 5-nitro-2-anthranilates of lanthanum(III), samarium(III), terbium(III), erbium(III) and lutetium(III) were obtained as hydrates having 2.5 mol of water molecules per 1 mol of compound. The compounds are isostructural. The processes of dehydration and rehydration were investigated. The first step of dehydration does not cause the change of crystal structure. The entire dehydration gives anhydrous compounds with different structure than the structure of hydrates. However, the dehydration of La, Sm, Tb and Er is reversible - the rehydration process gives the complexes having the same crystal structure as the initial compounds. Only the anhydrous lutetium complex under the influence of moisture does not give the starting compound. This revised version was published online in July 2006 with corrections to the Cover Date.     

Molecular dynamics study of the coordination sphere of trivalent lanthanum in a highly concentrated LiCl aqueous solution: a combined classical and ab initio approach

The first coordination sphere of trivalent lanthanum in a highly concentrated (14 M) lithium chloride solution is studied with a combination of classical molecular dynamics and density functional theory based first principle molecular dynamics. This method enables us to obtain a solvation shell of La3+ containing 2 chloride ions and 6 water molecules. After refinement using first principle molecular dynamics, the resulting cation-water and cation-anion distances are in very good agreement with experiment. The 2Cl- and the 6 water molecules arrange in a square antiprism around La3+. Exchange of water molecules was also observed in the first-principle simulation, with an intermediate structure comprising 7 water molecules stable for 2.5 ps. Finally, evaluation of dipole moments using maximally localized Wannier functions shows a substantial polarization of the choride anions and the water molecules in the first solvation shell of trivalent lanthanum.     

Coordination of ions in aqueous solutions of erbium chloride from X-ray diffraction data

Aqueous solutions of erbium chloride were studied by X-ray diffraction over a broad range of concentrations under standard conditions. The prepeaks observed in the experimental scattering intensity curves were interpreted. The solutions were found to possess two types of structures. Saturated and concentrated solutions down to molar ratio of 1 : 20 have a quasi-crystalline structure defined by inter-ion interactions. Dilute solutions form a water-like structure characterized by a tetrahedral network of hydrogen bonds between water molecules. It was found that prepeaks can also be seen in the intensity curves of dilute solutions, which implies that these solutions retain the so-called long-range order.     

Azido Homoalanine is a Useful Infrared Probe for Monitoring Local Electrostatistics and Sidechain Solvation in Proteins

The use of IR probes to monitor protein structure, deduce local electric field, and investigate the mechanism of enzyme catalysis and protein folding has attracted increasing attention. Here, the azidohomoalanine (Aha) is considered as a useful IR probe. The intricate details of the distinct effects of backbone peptide bonds and H-bonded water molecules on the azido stretch mode of the IR probe Aha were revealed by carrying out QM/MM MD simulations of two variants of the protein NTL9, NTL9-Met1Aha and NTL9-Ile4Aha and comparing the resulting simulated IR spectra with experiments.     

Thermogravimetric investigation of scandium,yttrium and the rare earth metal diliturates

Thermolysis curves for scandium, yttrium, lanthanum, cerium(III), neodymium, samarium, gadolinium, dysprosium and erbium diliturates are described, Scandium diliturate forms a 15-hydrate which dehydrates in 3 steps. The other diliturates all form 12-hydrates which dehydrate smoothly. All of the anhydrous diliturates are thermally stable to about 240°.Solubilities in water for scandium, yttrium, lanthanum, cerium(lll), neodymium, samarium. gadolinium, dysprosium and erbium diliturates are given. Scandium diliturate is the most soluble and neodymium diliturate the least soluble. Solubilities of rare earth diliturates not investigated can be predicted approximately.Methods for thermogravimetric determination of yttrium, lanthanum, neodymium, samarium, gadolinium, dyprosium, and erbium as the diliturates have been developed. The precipitates are quite dense, easily handled and filterable. Weighing as the diliturate salts gives these determinations a very favorable gravimetric factor.     

Specific features of the structure of a lanthanum nitrate complex with ethylenediamine

Anhydrous lanthanum nitrate and its complexes with one and two ethylenediamine molecules are calculated by the ab initio B3LYP/LANL2DZ quantum-chemical method. An ethylenediamine molecule is shown to coordinate preferentially through one amino group, and a hydrogen bond is formed between the coordinated amino and nitrato groups. An ethylenediamine complex of lanthanum nitrate is synthesized, and its composition and thermal stability are determined. The IR spectra of the ethylenediamine complex of lanthanum nitrate confirm the presence of the intramolecular hydrogen bond in this complex.     

Solvation structure and ion complexation of La3+ in a 1 molal aqueous solution of lanthanum chloride

H/D isotopic substitution neutron scattering and X-ray scattering have been used to investigate the short and intermediate range solution structure in a 1 m aqueous solution of lanthanum chloride. To improve the reliability of the local structural information on the cation environment, information has been incorporated from Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy data into the applied analytical framework. The markedly different structural sensitivities of the experimental probes allow the construction of a detailed three-dimensional atomistic model using the Empirical Potential Structure Refinement (EPSR) technique. The results show that at the investigated concentration La(3+) is hydrated by eight water molecules and one chloride ion, forming an inner-sphere ion complex in which the water molecules maintain angular configurations consistent with a tricapped trigonal prism configuration. This local geometry considerably disrupts the bulk solvent structure.