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1.
以钇(III)离子作为模板, 以4-乙烯吡啶(4-VP)、乙酰丙酮(Hacac)和钇(III)形成的三元配合物为功能单体、乙二醇二甲基丙烯酸酯(EDMA)为交联剂, 采用本体聚合法合成了钇(III)离子配位分子印迹聚合物. 系统研究了印迹聚合物对钇(III)离子的吸附性和选择性. 结果表明, 印迹聚合物对钇(III)离子有很好的亲和性, 达到吸附平衡的时间为60 min, 最大吸附量为12.4 mg•g−1, 重复使用时性能稳定, 而且印迹聚合物对钇(III)离子具有较强的选择性识别能力.  相似文献   

2.
The effects of concentration, pH and anions on the adsorption behaviour of xylenol orange (XO) on the strong anion exchangers, Amberlite IRA-400 and Hitachi 2632 are described. The adsorption behaviour of the XO complexes of Ce(III), Y(III), Sc(III) and U(VI) on the Amberlite IRA-400 resin as a function of XO concentration and pH is reported. A continuous-flow radiometric detector is used to investigate the separations of the Ce(III)—Sc(III), Y(III)—Sc(III), and Ce(III)—Y(III) pairs on the XO-form Hitachi 2632 resin column by pH control. Satisfactory separations of the Ce(III)—Sc(III) and Y(III)—Sc(III) pairs are achieved.  相似文献   

3.
This work presents an electrochemical study of Y(III) ions on W electrode and liquid Zn electrode and co-reduction mechanism of Y(III) and Zn(II) on W electrode in LiCl-KCl eutectic melts. Cyclic voltammogram and current reversal chronopotentiogram revealed that the electrochemical reaction of Y(III) on W electrode proceeds a single step mechanism of Y(III) to Y(0). On liquid Zn electrode, the deposition potential of Y(III) is more positive than that on W electrode due to the formation of Y-Zn solution and the reduction process was found to be a diffusion controlled and quasi-reversible at lower scan rate of 0.1 V/s. Based on the results of cyclic voltammometry, square wave voltammetry, and chronopoteniometry, the Y-Zn intermetallics could be formed by co-reduction process of Y(III) and Zn(II) on W electrode in LiCl-KCl-ZnCl2-YCl3 molten salts. Moreover, the electrochemical extracting metallic Y was conducted by galvanostatic and potentiostatic electrolysis on liquid Zn electrode. Electrolysis products consisted of Zn and YZn12 phases characterized by scanning electron microscopy with energy dispersive spectrometry and X-ray diffraction. Meanwhile, the change of Y(III) concentration in LiCl-KCl eutectic melts was detected by inductive coupled plasma atomic emission spectrometer and the extraction efficiency could be estimated.  相似文献   

4.
The effect of Y(III) and Gd(III) coactivator ions on the intensity of Eu(III) and Tb(III) luminescence in monomer and polymer mixed-metal complexes was studied. Isomorphic replacement of Eu(III) and Tb(III) ions by Y(III) and Gd(III) ions in macromolecular complexes led to sensitization of Eu(III) and Tb(III) ion luminescence. A mechanism of columinescence was suggested. It involves a charge transfer and the ligand orbitals and the vacant orbitals of Eu(III) and Tb(III) ions and coactivators.  相似文献   

5.
A new zirconium vanadate (Zr–V) ion-exchanger was synthesized and characterized for fast and selective separation procedure of 90Y from 89Sr. The method was based on 90Y(III) sorption from aqueous HCl solution containing 89Sr(II) onto Zr–V gel exchanger. The kinetics of Y(III) sorption from HCl solution by Zr–V exchanger was subjected to Weber–Morris, Lagergren, Bhattacharya and Venkobachar, and Bt models. Initially, the uptake of Y(III) onto the exchanger was fast followed by kinetically first-order sorption with an overall rate constant, K Lager = (3.55 ± 0.03) × 10?4 min?1. Film and intraparticle transport are the two steps that might influence Y(III) sorption. The negative values of ΔG of 90Y retention dictate that, the process is a spontaneous. The negative values of ΔH and ΔS reflect the exothermic nature of 90Y(IIsorption and the random uptake of 90Y(III) onto Zr–V sorbent. Zr–V exchanger offers unique advantages of 90Y(III) retention over conventional solid sorbents in rapid and effective separation of traces of 90Y(III) from Sr. The exchanger was successfully packed in column for an effective separation of 90Y.  相似文献   

6.
The extraction and preconcentration of a metal complex via surfactant-mediated phase separation was studied. A sensitive, selective and low-cost methodology for the determination of micro amounts of thorium, lanthanum and yttrium ions, using Eriochrome Cyanine R (ECR) with a flotation step prior to spectrophotometric determination was developed. The precipitate in the scum layer was quantitatively collected, stripped with 4 ml of 3% HCl and measured spectrophotometrically at 540 nm for Th(IV) and at 650 nm for both La(III) and Y(III). The stripping of Th(IV), La(III) and Y(III) from the scum layer was carried out in one step with different mineral acids. The stripping efficiency was found to be quantitative in the case of HCl. An excess amount of ECR was used to eliminate the interfering effects of various foreign species. The proposed procedure was applied to the determination of Th(IV), La(III) and Y(III) spiked in natural water samples and in some ore samples. Additionally, the mechanism of flotation of the metal chelate was proposed to be due to a physical interaction between the metal chelate and the oleic acid surfactant through the Van der Waals force.  相似文献   

7.
邻菲罗啉单氮氧化物(PhenNO),分子内存在较大的共轭π键,对过渡金属离子具有良好的配位性能,其中某些配合物具有荧光。迄今为止,Sc、Y与该配体的配合物尚未见文献报道。本文在非水介质中合成出Sc(Ⅲ)、Y(Ⅲ)盐与PhenNO的五个新配合物,研究了它们的组成及其有关性质。由于Sc(Ⅲ)和Y(Ⅲ)的离子半径不同,它们的配位行为及其配合物的性质应有差异,试验结果证实了预测的结果。  相似文献   

8.
The complexes of the reagent 5-Br-PADAP with the metal ions La(III), Ce(III), and Y(III) have been studied.The composition and stability of these complexes have been determined. A sensitive spectrophotometric procedure for the determination of the metal ions La(III), Ce(III), and Y(III) has been proposed. The limitations of this procedure and the effect of other ions have been studied.  相似文献   

9.
2,4,5-Trimethoxybenzoates of Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), Lu(III) and Y(III) are crystalline, hydrated salts with colours typical for M(III) ions. The carboxylate group is a bidenate, chelating ligand. The complexes of Tb(III), Dy(III) and Ho(III) are dihydrates while those of Er(III), Tm(III), Yb(III), Lu(III) and Y(III) are trihydrates. These compounds are characterized by low symmetry. On heating in air to 1273 K, the 2,4,5-trimethoxybenzoates of heavy lanthanides(III) and yttrium(III) decompose in two steps. At first they dehydrate to form anhydrous salts which next are decomposed to the oxides of the respective metals. The values of the enthalpy of dehydration process were determined. The solubility in water at 293 K for all heavy lanthanides(III) and yttrium(III) are in the orders of 10-3-10-4 mol dm-3. The magnetic moments of the complexes were determined in the temperature range 77-300 K.  相似文献   

10.
A novel "ditopic" ligand containing two monophosphinate triacetate DOTA-like units linked by a thiourea bridge has been synthesized and its complexes with Ln3+ ions (Ln = Y, Eu, Gd, Dy) investigated by NMR spectroscopy and relaxometry. The presence of one water molecule in the first coordination sphere has been determined by the measurement of the dysprosium(III)-induced 17O NMR shifts. The 1H and 31P NMR spectra of the Eu(III) derivative indicate a higher abundance of the fast-exchanging twisted square antiprismatic (m) isomer than the isomeric square antiprismatic (M; m/M = 3:2) complex. The analysis of the 89Y and 13C T1 NMR relaxation times in the Gd(III)/Y(III) mixed complex have provided useful structural information. Values of ca. 6.3 and 8.2 A for the Gd...Y and Gd...C distances, respectively, have been estimated which indicate a rather compact solution structure. This result finds support in the value of the relaxivity whose increase (at 20 MHz and 298 K) on passing from the monomeric (5.7 s(-1) mM(-1)) to the ditopic complex (8.2 s(-1) mM(-1)) can be attributed to the doubling of the inner-sphere term following the doubling of the molecular size. The structural and dynamic relaxivity-controlling parameters were assessed by a simultaneous fitting of the variable temperature 17O NMR and 1H NMRD relaxometric data. The mean water residence lifetime (298tauM) has been found to be 53 ns, one of the shortest values reported for ditopic complexes. The reorientational correlation time is two times longer (298tauR = 183 ps) than the corresponding value of the parent monomeric Gd(III) complex, thus supporting the view of a limited degree of internal rotation. The possible influence of magnetic Gd-Gd coupling has been excluded by a comparison of the 1H NMRD profiles of the homodinuclear Gd(III)/Gd(III) and the heterodinuclear Gd(III)/Y(III) complexes.  相似文献   

11.
N,N,N',N'-tetraoctyl diglycolamide (TODGA) has been used as the stationary phase in an extraction chromatography resin (XCR) material prepared for evaluating the uptake and the separation behaviour of (90)Y and (90)Sr from acidic feeds. Chromosorb-W was used as the solid support material while the feed solution was usually 4M HNO(3). The batch uptake studies have suggested almost no Sr(II) uptake while Y(III) uptake increased with acidity up to 4M HNO(3) beyond which a decrease in the K(d,w) values were observed. Column studies were carried out and breakthrough profiles were obtained for both Y(III) and Sr(II). No breakthrough of Y(III) was noticed even when >50 column volumes of the feed (carrier free (90)Y at 4 M HNO(3)) was passed through the column while about 20 column volumes were required for the breakthrough of Y(III) when the feed contained 1 g/L Y in 4 M HNO(3) spiked with (90)Y tracer. The reusability of the column was also studied which indicated in the deterioration of the column performance as shown by the sharp fall in the breakthrough volumes and was attributed to the probable leaching of the reagent from the support material. The role of absorbed dose was also investigated for Y(III) uptake. Separation of carrier free (90)Y tracer was carried out by loading the column with (90)Sr and eluting with 0.01M solutions of HNO(3) as well as EDTA. The purity of the product was ascertained by half-life method.  相似文献   

12.
The complexes of heavy lanthanides and yttrium with 2,3-dimethoxybenzoic acid of the formula: Ln(C9h9O4)3·nH2O, where Ln=Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), Lu(III), Y(III), and n=2 for Tb(III), Dy(III), Ho(III), Y(III), n=1 for Er(III), Tm(III), n=0 for Yb(III) and Lu(III) have been synthesized and characterized by elemental analysis, ir spectroscopy, thermogravimetric studies and x-ray diffraction measurements. The complexes have colours typical for Lnł3+ ions (Tb(III), Dy(III), Tm(III), Yb(III), Lu(III), Y(III) - white; Ho(III) - cream and Er(III) - salmon). the carboxylate groups in these complexes are a symmetrical, bidentate, chelating ligand or tridentate chelating-bridging. they are isostructural crystalline compounds characterized by low symmetry. On heating in air to 1273 k the 2,3-dimethoxybenzoates of heavy lanthanides and yttrium decompose in various ways. The complexes of Tb(III), Dy(III), Ho(III), Er(III), Tm(III) and Y(III) at first dehydrate to form anhydrous salts which next are decomposed to the oxides of the respective metals. 2,3-dimethoxybenzoates of Yb(III) and Lu(III) are directly decomposed to oxides. When heated in nitrogen the hydrates also dehydrate in one step to form the anhydrous complexes that next form the mixture of carbon and oxides of respective metals or their carbonates. The solubility of the yttrium and heavy lanthanide 2,3-dimethoxybenzoates in water at 293 k is of the order of 10-2 mol dm-3. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
Carbonate-assisted hydrolysis of Y or Yb(III) ions in the presence of the trivacant Wells-Dawson polyoxoanion, alpha-[P(2)W(15)O(56)](12-), produced two polyoxometalate-supported Y- or Yb(III)-hydroxo/oxo clusters, which have been characterized by single-crystal X-ray structure determination. The structure of the Y complex consists of a distorted Y(4)(OH)(4) cubane cluster encapsulated by two lacunary alpha-[P(2)W(15)O(56)](12-) units, while the Yb cluster features a hexametallic core centered around a mu(6)-oxo atom with each Yb(3)(III) triangular face capped by an oxo or a hydroxo group. Magnetization measurements of the ytterbium(III) derivative suggested that intermolecular dipolar exchange is present at low temperatures (below 15 K). Despite its absence in the structures themselves, control experiments show that carbonate not only functions in the hydrolysis, it also influences the structure of the complexes by complexation to yttrium and the f-block elements.  相似文献   

14.
Journal of Radioanalytical and Nuclear Chemistry - To separate Y(III) from a Sr(II)–Y(II) mixture, two silica-based adsorbents, CMPO/SiO2-P and (CMPO?+?Dodec)/SiO2-P were prepared...  相似文献   

15.
Reaction of A-alpha-PW(9)O(34)(9)(-) with YCl(3) in an aqueous Na(2)CO(3) solution produces a dianion-encapsulated A-type sandwich polyoxometalate, (YOH(2))(3)(CO(3))(A-alpha-PW(9)O(34))(2)(11)(-). The X-ray structure of this complex reveals that three Y(III) ions are sandwiched between two A-alpha-PW(9)O(34)(9)(-) moieties and that a carbonate dianion is encapsulated in the same plane as the three Y(III) atoms. The oxygen atoms of the CO(3)(2)(-) are sitting at the midpoints of the sides of the triangle formed by the three Y(III) ions. (31)P and (13)C NMR studies confirm that this complex is significantly more stable than the analogous A-type sandwich polyoxometalates containing divalent metals.  相似文献   

16.
The position of scandium and yttrium within lanthanides in respect to the enthalpies of solution of anhydrous rare earth halides has been discussed. It has been indicated that although the respective shift of Sc(III) as a quasi-heavy lanthanide is less pronounced than for Y(III), the overall covalency within the trivalent ions of the scandium group, Ln(III) and An(III) included, is the most pronounced for Sc(III) due to participation of the empty orbitals in bonding: Sc(III)>An(III)>Ln(III)> Y(III). The irregularity of this trend is produced by the superimposed participation of the 5f (An(III)) and, to a lesser extent, of the 4f (Ln(III)) orbitals in bonding. The crucial factor of a maximum difference between the product and substrate coordination number (CN) of the central ion for covalency, separation factor and isotope effect in chemical exchange is emphasized.  相似文献   

17.
IntroductionItiswellknownthatyttriumcanbeusedinmanyfields ,suchasmetallurgy ,ceramics ,lasersandelectron ics ,especiallyinfluorescentmaterialswhoseneedforhighpurityyttriumoxideisincreasing .InChina ,there sourceofyttriumisrich ,andthehighpureyttriumisbe ingo…  相似文献   

18.
The polyamino ligand 1,4,7-tris(2-aminoethyl)-1,4,7-triazacyclononane (1) has been used to synthesise two new ligands by Schiff-base condensation with methyl sodium acetyl phosphonate to give ligand L and methyl sodium 4-methoxybenzoyl phosphonate to give ligand L1 in the presence of lanthanide ion as templating agent to form the complexes [Ln(L)] and [Ln(L1)](Ln = Y, La, Gd, Yb). Both ligands L and L1 have nine donor atoms comprising three amine and three imine N-donors and three phosphonate O-donors and form Ln(III) complexes in which the three pendant arms of the ligands wrap around the nine-coordinate Ln(III) centres. Complexes with Y(III), La(III), Gd(III) and Yb(III) have been synthesised and the complexes [Y(L)], [Gd(L)] and [Gd(L1)] have been structurally characterised. In all the complexes the coordination polyhedron about the lanthanide centre is slightly distorted tricapped trigonal prismatic with the two triangular faces of the prism formed by the macrocyclic N-donors and the phosphonate O-donors. Interestingly, given the three chiral phosphorus centres present in [Ln(L)] and [Ln(L1)] complexes, the three crystal structures reported show the presence of only one diastereomer of the four possible. 1H, 13C and 31P NMR spectroscopic studies on diamagnetic [Y(L)] and [La(L)] and on paramagnetic [Yb(L)] complexes indicate the presence in solution of all the four different diastereomers in varying proportions. The stability of complexes [Y(L)] and [Y(L1)] in D2O in both neutral and acidic media, and the relaxivity of the Gd(III) complexes, have also been investigated.  相似文献   

19.
Liu Y  Sun X  Luo F  Chen J 《Analytica chimica acta》2007,604(2):107-113
A new material (IL923SGs) composed of ionic liquids and trialkyl phosphine oxides (Cyanex 923) for Y(III) uptake was prepared via a sol-gel method. The hydrophobic ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate (C8mim+PF6) was used as solvent medium and pore templating material. The extraction of Y(III) by IL923SGs was mainly due to the complexation of metal ions with Cyanex 923 doped in the solid silica. Ionic liquid was stably doped into the silica gel matrix providing a diffusion medium for Cyanex 923, and this will result in higher removal efficiencies and excellent stability for metal ions separation. IL923SGs were also easily regenerated and reused in the subsequent removal of Y(III) in four cycles.  相似文献   

20.
Al(III), Ga(III), and In(III) complexes with octaphenyltetraazaporphine and halide axial ligands of the composition [(X)MTAP] (X = F, Cl, Br) and In(III) complexes with bidentate ligands of the composition [(Y)InTAP] (Y = nitrite (NO2) and 2,3-naphthodiolate (NpO2)) were synthesized. The acid–basic properties of the complexes were studied in the proton-donor media and the concentration stability constants of the acidic forms obtained at the first protonation stage were determined. The effect of the nature of a metal and extra ligand on the basic properties of meso-nitrogen atom in macrocyclic ligand was discussed.  相似文献   

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