Adsorption of Rare Earth Ion La(Ⅲ) on Yunnan Bowl Tea Surface from Aqueous Solution

The adsorption characteristics of rare earth ion La(Ⅲ) on Yunnan bowl tea surface from aqueous solution and effects of various surfactants on the adsorption were studied. It was found that Yunnan bowl tea can adsorb strongly La(Ⅲ) and pH may affect drastically the adsorption amount of La(Ⅲ). The adsorption law of La(Ⅲ) on Yunnan bowl tea surface follows the Langmuir equation. The maximum adsorption amount of La(Ⅲ) can reach 15 mg·g (-1). A comprehensive adsorption model is suggested according to the experimental results.

稀土Er(Ⅲ)对短程硝化性能的影响及其抑制动力学特性

研究了重稀土元素铒[Er(Ⅲ)]对短程硝化工艺的短期和长期脱氮效能影响,并进行了相关动力学分析。短期实验表明,0~10mg/L的Er(Ⅲ)对AOB菌活性呈现促进作用,20~60mg/L的Er(Ⅲ)对AOB菌活性呈现轻度抑制,80~120mg/L的Er(Ⅲ)则对AOB菌活性呈现重度抑制。AOB菌会吸附大量Er(Ⅲ),在进水Er(Ⅲ)浓度低于60mg/L时,Er(Ⅲ)去除率均大于90%,高于60mg/L后Er(Ⅲ)去除率逐渐降低。ICP-MS和EDS分析结果表明,Er(Ⅲ)可被AOB菌胞外吸附和胞内摄取,其中又以胞外吸附为主。分别采用Vadivelu模型、Hellinga模型、Michaelis-Menten模型和Hill模型对实验结果进行拟合,结果表明通过分段拟合(0~60mg/L和60~120mg/L) Hill模型能较好的描述Er(Ⅲ)对AOB菌的抑制动力学过程,拟合得到的R2分别为0.9879和0.9999,最大基质去除速率qmax(ΔSNPR)分别为2.59mg/(g·h)和7.15mg/(g·h)。长期试验表明,10mg/L的Er(Ⅲ)将使短程硝化系统性能逐渐消失,停止添加Er(Ⅲ)后,反应系统性能也不能恢复。

联苯二甲酸的钐(Ⅲ)配合物的合成、晶体结构及性质研究

在水热条件下,将配体2,2’-联苯二甲酸和Sm_(2)O_(3)反应合成了配合物1([Sm(bda)_(1.5)(H_(2)O)])。利用单晶X-射线、元素分析和热重分析对生成的晶体进行了表征和荧光性、热稳定性等性质检测。结果表明,该晶体属于单斜晶系C 2/c空间群的一维链结构。Sm1(Ⅲ)采取八配位的反四棱柱几何构型,而Sm2(Ⅲ)采取八配位的四棱柱几何构型,羧基分别采用μ2-η^(2):η^(1)和μ2-η^(1):η^(1)两种配位模式,bda^(2-)阴离子作为μ3-桥连结Sm(Ⅲ)离子形成1D链结构;进一步,通过π-π和C-H…π堆积作用形成2D和3D结构。配合物1能发出荧光,在141℃以下稳定存在,最终残留物为Sm_(2)O_(3)。

Synthesis of Eu(Ⅲ) and Tb(Ⅲ) Complexes with New Aryl Amide Type Tetrapodal Ligand and Their Luminescence Properties

A new aryl amide type tetrapodal ligand L (1, 1, 1, 1 tetrakis-{[(2 benzylaminoformyl) phenoxyl]methyl}methane) and its europium and terbium nitrate complexes were synthesized. The luminescence properties of these complexes were also studied.

Intercalation Assembly, Characterization and Luminescent Properties of Novel Supramolecular Composite Materials, Tb(Ⅲ) Complex with Tetrapodal Ligand-Montmorillonite

Two kinds of Tb（ Ⅲ ） complexes with tetrapodal ligand, [TbL（NO3）]^3＋ and [TbL]^3＋ （L： 1,1, 1＇, 1＇-tera （ 2-pyridinecarboxylester ）-di （ trimethylpropane）） were intercalated into the interlayer space of montmorillonite （MT） by ion exchange and coordination reaction of L with the Tb^3＋ ion existing in the interlayer space of Tb-MT respectively. The obtained luminescent supramolecular composite materials, [ TbL （NO3） ]^2＋-MT and [TbL]^3＋-MT were characterized by elemental analysis, XRD, FT-IR, UV-vis and thermal analysis. At the same time, the luminescent properties of the materials were also studied. The results show that the intercalated materials with regular layered structure, good thermal stability and the interlayer spacing （d001） approximates to the size of the complex ions which are located in the interlayer space of MT in the form of a monolayer.

Synthesis and Characterization of Some Lanthanide(Ⅲ) Complexes with 4-[N-(2-methoxybenzylimine)formyl]-2, 3-dimethyl-1-phenyl-3-pyazolin-5-one

A series of seven novel lanthanide（Ⅲ ） nitrato complexes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-phenyl-3-pyazolin-5-one （2mbfa）, were synthesized. These complexes were characterized by elemental analysis, molecular mass determination, conductance and magnetic moment measurements, IR, UV-visible, and ^13CNMR spectral studies, In these complexes, the Schiff base, 2mbfa, acts as neutral bidentate ligand by utilizing the carbonyl oxygen and azomethine nitrogen as donor sites. All the three nitrate ions are also coordinated unidentately with 7 coordination for the lanthanide（Ⅲ） ions with a tentative monocapped octahedral geometry for the complexes. All the seven lanthanide（Ⅲ） complexes have a general formula, [ Ln（2mbfa）：（NO3）3 ].

Crystal Structure and Fluorescent Study of a Binuclear Europium(Ⅲ) Complex

A novel binuclear Eu（Ⅲ） complex [Eu2（dpa dioxide）2（NO3）4（bpdioxide）-（EtOH）] （dpa dioxide = di-2-pyridylamine N,N＇-dioxide, bpdioxide = 2,2＇-bipyridine N,N＇-dioxide） has been synthesized and it exhibits strong and sharp fluorescent emission at 614 nm under UV radiation of 245 nm at room temperature. X-ray structural determination indicates two independent Eu（Ⅲ） ions in the structure with different EuO8N and EuOgN environments. The compound crystallizes in the triclinic system, space group P1, with a = 10.8089（7）, b = 11.4670（8）, c = 17.1440（12） A, α = 92.834（2）, β = 93.854（3）, γ = 95.433（2）°, Z = 2, Dc = 1.876 g/cm3, V= 2107.3（2） A3, F（000） = 1168.0, the final R = 0.032 and wR = 0.086 for 6331 observed reflections with I 〉 2σ（I）.

Synthesis, Structure and Properties of a Two-dimensional Samarium(Ⅲ) Complex of 1,3-Benzenedicarboxylic Acid and 1,10-Phenanthrolin

The title complex [Sm2（bdc）3（phen）2]n （1, H2bdc = 1,3-benzenedicarboxylic acid, phen = 1,10-phenanthrolin）, a new samarium（III） complex based on ligand H2bdc and 1,10-phen- anthrolin, has been hydrothermally synthesized and characterized by elemental analysis, FT-IR, and single-crystal X-ray diffraction. The crystal structure reveals that the Sm（1） centre adopts an eight-coordinated distorted square anti-prism coordination geometry, while the Sm（2） centre adopts a nine-coordinated distorted monocapped square prism coordination geometry. The ligand bdc2- takes two different connecting modes and links the Sm（llI） centers to give rise to a 2D network structure. Further, 2D layers of 1 are connected together to form a 3D structure through C-H-O hydrogen bonding interactions. The luminescent property and thermal stability of complex 1 are studied. 1 belongs to the triclinic system, space group P1 with a = 10.7367（5）, b = 14.3750（7）, c = 13.7505（3）A, a = 92.8840（10）, β = 104.4010（10）, ）, = 98.1400（10）°, Z= 2, V= 2143.44（18） A3, Mr = 1153.44, Dc = 1.787 g/cm3, F（000） = 1128,μ= 2.784 mm-1, the final R = 0.0279 and wR = 0.0720 for 8226 observed reflections with 1 〉 2σ（I）.

Microwave assisted synthesis, spectroscopic, thermal, and antifungal studies of some lanthanide(Ⅲ) complexes with a heterocyclic bishydrazone

A bishydrazone formed by the condensation of isatinmonohydrazone and salicylaldehyde reacted with lanthanide（Ⅲ） chloride to form complexes of the type [Ln（HISA）2Cl3], where, Ln=La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, Nd（Ⅲ）, Sm（Ⅲ）, Eu（Ⅲ）, or Gd（Ⅲ） and HISA= [（2-hydroxybenzaldehyde）-3-isatin]bishydrazone. Both reactions were carried out under microwave conditions. The ligand and the metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV visible, infrared, far infrared, and proton NMR spectral data. The ligand acted as neutral tridentate, coordinating through the carbonyl oxygen, azomethine nitrogen, and phenolic oxygen without deprotonation. The ligand and lanthanum（Ⅲ） complex were subjected to X-ray diffraction studies. The X-ray diffraction pattern of ligand exhibited its crystalline nature and that of the lanthanum（Ⅲ） complex indicated its amorphous character. The thermal decomposition behaviour of the complex, [La（HISA）2Cl3], was examined in the temperature range of 40-800 ℃ using TG, DTG, and DTA. The ligand and the metal complexes were screened for their antifungal activities.

Eu(Ⅲ) complexes involving 1,3,5-triazine diphosphine oxides

The 1,3,5-triazine diphosphine oxide ligands with donor-acceptor properties formed strong complexes with europium（Ⅲ） ion in acetonitrile. Spectrophotometric titrations and mass spectra indicated that two ligands coordinated to one europium ion. The stability constants varied from 11.64 to 14.60 （log 13）. Binary complexes exhibited rather weak luminescence in solution. 1,3,5-triazine diphosphine oxides engaged as co-ligands in Eu（Ⅲ） （2-thenoyltrifluoroacetonate）3 complex contributed to the overall photoluminescence and allowed for excitation with longer wavelengths than the parent complex.

Synthesis and Thermal Decomposition Kinetics of La(Ⅲ) Complex with Unsymmetrical Schiff Base Zwitterion Ligand

A new unsymmetrical solid Schiff base (LLi) was synthesized using L-lysine, o-vanillin and 2-hydroxy-l-naphthaldehyde. Solid La(Ⅲ) complex of this ligand [LaL(NO3)](NO3)·2H2O was prepared and characterized by elemental analyses, IR, UV and molar conductance. The thermal decomposition kinetics of the complex for the second stage were studied under non-isothermal condition by TG and DTG methods. The kinetic equation may be expressed as: dα/dt=A·e-E/RT·(1-α)2. The kinetic parameters(E, A), activation entropy S≠ and activation free-energy G≠ were also gained.

Microwave assisted synthesis,spectroscopy and biochemical aspects of lanthanum(Ⅲ) and praseodymium(Ⅲ) complexes with oxadiazole functionalised dithiocarbazinates

The new lanthanum (Ⅲ) and praseodymium (Ⅲ) complexes of the general formula [Ln(L)3] (Ln=La(Ⅲ) or Pr(Ⅲ); LK=potassium salt of dithiocarbazinates) were prepared by both, conventional thermal and by the use of microwave technology. Elemental analyses, electrical conductance, magnetic moment and electronic, infrared, far-infrared, 1H and 13C NMR spectral studies were used to characterize the complexes. The molecular weights of few complexes were determined by FAB-mass spectra. Nephelauxetic ratio, covalency parameter and bonding parameter for these complexes were also calculated. The probable structures of the complexes were proposed. The antifungal and antibacterial activities of the complexes were evaluated. The activities were correlated with the structures of the compounds.

Syntheses aod Crystal Structures of Rare Earth Complexes with Adamantanecarboxylic Acid, [LnL_3(HL)(H_2O)]_2·2EtOH·2H_2O (Ln=Nd (1), La (2))

The title complexes （LnL3 （HL） （H2O） ]2· 2EtOH·2H2O （Ln= Nd （1）, La （2）, HL=adamantanecarboxylic acid） were prepared and determined by single-crystal X-ray diffraction. Both complexes crystallize in triclinic system with space group P 1^-, cell parameters are： complex （1） a = 1.0556（2） nm, b =1.4913（3） nm, c = 1.4920（3） nm, a = 106.26 （3）°, β=93.51（3）°, γ=97.23（3）°, V=2.2253 （5） nm^3, Dcal=1.409 g · cm^-3, Z = I , F （ 000 ） = 990, μ（Mo Kα） = 1. 225 mm^-1, M, = 1884.50; complex （2） a = 1.0453（2） nm, b = 1.4971（3）nm, c = 1.5052（3） nm, α = 106.07（3）°, β =93.58 （3）°, γ=97.56（3）°, V=2.2391（5）nm^3, Dcal= 1.397 g·cm^-3, Z = 1, F（000） =984, μ（Mo Kα） = 1.015 mm^-1, Mr= 1877.88. The final R and wR are 0. 0396 and 0. 1062 for 8589 （1 ≥ 2σ （I）） observed reflections for complex （1）, 0.0505 and 0. 1344 for 8417 （ 1 ≥ 2σ （1） ） observed reflections for complex （2）, respectively. The crystals are consisted of a binuelear molecule. The coordination geometry of the Ln（ Ⅲ ） ion can be described as trieapped trigonal prism.

Synthesis, Characterization and Crystal Structure of Quaternary Complex of Gadolinium (Ⅲ)

A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 473 and 1.880 in poly crys talline powder at room temperature is quite different from the U spectrum. The c oordination number of Gd 3+ is nine with a monocapped square antiprism geom etry. And the stacking effect was observed in the complex. The crystal of the co mplex belongs to triclinic with space group P 1, a=0.9626(4) n m, b=0.9732(4) nm, c=1.1758(5) nm, α=102.45(1)°, β=108.16(1) °, γ=96.68(2)°, V=1.0018(7) nm3, Z=2, D c=1.80 g·cm -3 , μ(MoKα)=33.63 mm -1, F(000)=530, GOF=1.80, R=0.023 and R w=0.027.

Synthesis, Characterization, Thermal Decomposition Mechanism and Non-Isothermal Kinetics of Salicylaldehyde Salicylhydrazone and Its Complex of Erbium(Ⅲ)

The salicylaldehyde salicylhydrazone and its complex of Er(Ⅲ) were synthesized. The formulae K·4H_2O(HL=[C_(14)H_(10)N_2O_3]^(2-), the bivalent form of the salicylaldehyde salicylhydrazone) were determined by elemental analysis and EDTA volumetric analysis. Molar conductance, IR, UV and X-ray power diffraction were carried out for the characterizations of the complex and the ligand. There are two stable five-numbered and six-numbered circles in the complex. The thermal decompositions of the ligand and the complex with the kinetic study are carried out by non-isothermal thermogravimetry. The stages of the decompositions were identified by TG-DTG curve. The non-isothermal kinetic data were analyzed by means of integral and differential methods. The possible reaction mechanism and the kinetic equation were investigated by the corresponding kinetic parameters.The activation energy value of the main step decomposition are also calculated by Kissinger′s method and Ozawa′s method.

Syntheses and Structural Studies of Nine-Coordinate Mononuclear K[Eu~Ⅲ(edta)(H_2O)_3]·3.5H_2O and Binuclear K_4[Eu~~Ⅲ__2(Httha)_2]·13.5H_2O Complexes

The crystal and molecular structures of K[Eu~Ⅲ(edta)(H_2O)_3]·3.5H_2O (H_4 edta=ethylenediaminetetraacetic acid) and K_4[Eu~~Ⅲ__2(Httha)_2]·13.5H_2O (H_6 ttha=triethylenetetraminehexaacetic acid) complexes were determined by single-crystal X-ray structure analyses. The crystal of K[Eu~Ⅲ(edta)(H_2O)_3]·3.5H_2O complex belongs to orthorhombic crystal system and Fdd2 space group. The crystal data are as follows: a=1.9849(6)nm, b=3.5598(11)nm, c=1.2222(4)nm, V=8.636(5)nm^3, Z=16, M=596.37, D_c=1.835 g·cm^(-3), μ=3.166 mm^(-1) and F(000)=4752. The final R and wR values are 0.0269 and 0.0692 for 2936 [I>2.0σ(I)] reflections, and 0.0317 and 0.0708 for all 7284 unique reflections, respectively. The [Eu~Ⅲ(edta)(H_2O)_3]-complex anion has a nine-coordinate pseudo-monocapped square antiprismatic structure in which the nine coordinate atoms, two N and seven O are from one edta ligand and three water molecules. The crystal of the K_4[Eu~Ⅲ_2(Httha)_2]·13.5H_2O complex belongs to monoclinic system and P2(1)/n space group. The crystal data are as follows: a=1.1337(3) nm, b=2.5753(6) nm, c=2.2138(6) nm, β=102.871(5)°, V=6.301(3) nm^3, Z=4, M=1682.33, D_c=1.773 g·cm^(-3), μ=2.339 mm^(-1) and F(000)=3404. The final R and wR are 0.0514 and 0.0906 for 11144 [I>2.0σ(I)] reflections, and 0.0976 and 0.1068 for all 26048 unique reflections, respectively. The complex molecule is composed of two close parts in structure. Every part around the Eu~Ⅲ ion in the [Eu~~Ⅲ__2(Httha)_2]^(4-) complex anion has a nine-coordinate structure with distorted monocapped square antiprismatic prism, in which the ttha ligand coordinates to one central Eu~Ⅲ ion with three N atoms and four O atoms and to the other Eu~Ⅲ ion with two O atoms.

Structure and Bonding in Some Gd(Ⅲ) Metal Complexes Studied by Three-Dimensional X-Ray Analysis and ^(155)Gd Mssbauer Spectroscopy

Some functional lanthanide metal complexes, such as acetylacetonato complexes, ethylenediaminetetraacetato complexes, were successfully applied for diagnostic technique. The authors are interested in investigating the structure and bonding in lanthanide and actinide metal complexes using 166Er, t55Gd, and 237Np Mtissbauer spectroscopies in connection with single-crystal and/or powder X-ray diffraction, making clear the differences on their structures as well as the differences in the participation of 4f and 5f orbitals in the chemical bonds. In this article, the crystal structures of two novel Gd（Ⅲ） acetylacetonato complexes, Gd（pta）3 · 2H2O （pta = 1,1,1 -trifluoro-5,5-dimethy 1-2,4-hexanedione） and Gd（bfa）3 · 2H2O （bfa = 1, 1, 1 -trifluoro-4-phenyl-2-4-butanedione） were reported. Though both of them were dihydrate and had distorted square antiprismatical structure, Gd（pta）3 · 2H2O crystallizes in the P 2 1/n （#14） monoclinic space group and its lattice parameters are a = 1.4141（6） nm, b = 1.0708（3） nm, c =2.2344（4） nm, β =952.4（2）°, and Gd（bfa）3· 2H2O crystallizes in P 212121 orthorhombic space group and its lattice parameters were a = 1.322 （1） nm, b = 2.295 （1） nm, c = 1. 0786（8） nm. In the meantime, the authors had finished a systematic investigation on the ^155Gd Mossbauer isomer shift （δ） of various Gd（Ⅲ） metal complexes having a different coordination number （C.N.） and different ratios coordinating oxygen to nitrogen. A tendency for the 6 value to decrease with an increase in the C.N, and the number of the nitrogen atom coordinating to Gd was confirmed. This indicated that the Gd-O and/or Gd-N bond in the investigated Gd（Ⅲ） metal complexes had a small covalent contribution, which was possible to be deduced from the O and/or N atoms of the lisands donating electrons to 6s, 5d, and 4f orbitals of Gd.

Hydrothermal Synthesis and Crystal Structure of a New Dimeric Lanthanum (Ⅲ) Complex

A new dimeric lanthanum (Ⅲ) complex [La_2(phen)_2(C_7H_3N_2O_6)_6] (phen=1, 10-phenanthroline) was synthesized by the hydrothermal method and determined by single crystal X-ray diffraction analysis. The La(Ⅲ) ion is coordinated to seven oxygen atoms from five carboxylate groups and two nitrogen atoms from a phen ligand, forming a monocapped square antiprismatic geometry. Six carboxylate groups coordinate to two La(Ⅲ) ions in three modes which are chelating bidentate, bridging bidentate and bridging tridentate. The crystal is triclinic with space group P-1, a=1.2030(4) nm, b=1.2962(5) nm, c=1.3330(5) nm, α=104.410(5)°, β=114.048(4)°, γ=100.054 (4)°, V=1.7467 (10) nm^3, M_r=952.46, Z=2, D_c=1.811 g·cm^(-3), F(000)=944, S=1.017, μ=1.320 mm^(-1), with R1=0.0298 and wR2=0.0625.

Studies on some lanthanide（Ⅲ） complexes with 4-hydroxyantipyrine

Seven new lanthanide（Ⅲ） complexes with 4-hydroxyantipyrine were synthesized. These complexes were characterized by elemental analysis, molar conductance, magnetic moment measurements, FT-IR, electronic and 1HNMR spectra, X-ray powder diffraction, and thermogravimetric studies. The ligand, 4-hydroxyantipyrine （hap）, contained carbonyl oxygen and hydroxyl oxygen as potential donor sites. On coordination, deprotonation occurred and as a result, hap acted as a monobasic bidentate ligand. A coordination number 6 was assigned to the lanthanide（Ⅲ） ions in these complexes with orthorhombic structure. All the complexes were thermally stable-150℃ and underwent decomposition in three stages with the formation of Ln2O3 as the final residues.

Syntheses and Crystal Structure of Nine-Coordinate Mononuclear Na[ EuⅢ (edta)(H2O)3] · 4H2O and Binuclear Na4[Eu2Ⅲ(Httha)2]·10H2O Complexes

The crystal and molecular structures of the Na[Eu Ⅲ (edta) ( H2 O) 3] · 4H2O ( edta = ethylenediaminetetraacetic acid) and Na4[Eu2Ⅲ (Httha)2] · 10H2 O ( ttha = triethylenetetraminehexaacetic acid) complexes were determined by single-crystal X-ray structure analyses.The crystal of Na[ EuⅢ (edta) (H2O)3] · 4H2O belongs to orthorhombic crystal system and Fdd2 space group.The crystal data are as follows: a = 1.9415 (15)nm, b = 3.544(3 )nm, c = 1.203(9)nm, V = 8.327(5)nm3, Z = 16, M = 589.27, Dc= 1.880 g· cm-3, μ= 3.108mm-1 and F(000) = 4704.The final R and wR values are 0.0312 and 0.0750 for 2091[I ＞ 2.0σ (I)] reflections, and 0.0344and 0.0766 for all 3932 unique reflections, respectively.The[EuⅢ (edta) (H2O) 3] - anion has a nine-coordinate pseudo-monocapped square antiprismatic structure in which the nine coordinate atoms, two N and seven O, are from one edta ligand and three water molecules.The crystal of Na4[Eu2Ⅲ (Httha)2] · 10H2O belongs to orthorhombic system and Pccn space group.The crystal data are as follows: a = 2.610(3)nm, b = 2.089(3)nm, c = 2.239(3)nm, V =12.208 ( 28 ) nm3, Z = 8, M = 1548.92, Dc= 1.686g·cm-3,μ = 2.115 mm-1andF(000) = 6272.Thefinal R and wR are 0.0625 and 0.1091 for 9834[I ＞ 2.0σ(I)] reflections, and 0.1608 and 0.1471 for all 37818 unique reflections, respectively.The whole complex molecule is composed of two close parts in which each one has a nine-coordinate structure with distorted monocapped square antiprismatic prism.The ttha ligand in the[Eu2Ⅲ (Httha)2] 4- anion coordinates to one Eu Ⅲ ion with three N atoms and four O atoms and to the other Eu Ⅲ ion with two O atoms.