亚氨基二乙酸树脂吸附钇(Ⅲ)的研究

The adsorption behavior and mechanism of a novel chelate resin, iminodiacetic acid resin (IDAAR) for Y(Ⅲ) were investigated. The statically saturated adsorption capacity is 102mg·g^-1 resin at 298K in HAc-NaAc medium at pH 5.7. Y(Ⅲ) adsorbed on IDAAR can be reductively eluted by 1.0～4.0mol·L^-1 HCl used as eluant and the elution percentages are almost as high as 100%. The resin can be regenerated and reused without apparent decrease in adsorption capacity. The apparent adsorption rate constant is k₂₉₈=3.36×10^-5s^-1. The adsorption behavior of IDAAR for Y(Ⅲ) conforms to Freundlich′s model reasonably. The thermodynamic adsorption parameter, enthalpy change ΔH of IDAAR for Y(Ⅲ) is 18.6kJ·mol^-1. The complex molar ratio of the functional group of IDAAR to Y(Ⅲ) is about 3∶1. The adsorption mechanism of IDAAR for Y(Ⅲ) was examined by using chemical method and IR spectrometry.     

复盐法制备无水氯化镁的热解机理及动力学研究

The complex compound (MgCl₂·C₆H₅NH₂·HCl·6H2O) was prepared by reaction of C₆H₅NH₂·HCl with MgCl₂·6H₂O. Reaction mechanism and kinetics of the compounds decomposition were studied by means of the TG-DTA-MS coupling technique and the TG-DTA technique. The results show that there are four steps in the complex′s thermal decomposition, the first two steps correspond to the loss of six crystal waters and the last two steps loss one Aniline hydrochloride. The first three steps belong to the R2 mechanism with 2-dimentional phase boundary reaction as the control step, and the last step belongs to the D3 with 3-dimensional diffusion (sphere Jander equ.) as the control step. The apparent active energy of four steps are, 127.4 kJ·mol^-1, 124.8 kJ·mol^-1, 142.3 kJ·mol^-1 and 329.0 kJ·mol^-1, respectively and the frequency factor are 1.28 × 10¹⁸ s^-1, 7.94 × 10¹⁵ s^-1, 5.98 × 10¹⁶ s^-1 and 4.39 × 10³⁴ s^-1, respectively.     

Temperature effected sorption of europium(III) onto 1-(2-pyridylazo)-2-naphthol impregnated polyurethane foam

Summary The sorption of Eu(III) ions onto PAN loaded PUF has been optimized and investigated under the influence of various temperatures, i.e., 303, 313 and 323 K. Maximum retention (>96%) of Eu(III) ions (1.79^. 10^-5M) onto PAN loaded PUF (7.75 mg^. ml^-1) was achieved after 30-minute equilibration time from pH 7 buffer solution. The variation of sorption with temperature yields the thermodynamic parameters ΔH=79±2 kJ^. mol^-1, ΔS=276±7 kJ^. mol^-1. K^-1and ΔG=-1.4±0.1 kJ^. mol^-1at 298 K. The positive value of enthalpy and negative free energy show endothermic and spontaneous nature of sorption, respectively. The sorption data followed Freundlich, Dubinin-Radushkevich (D-R) and Langmuir isotherms at all the three given temperatures. The Freundlich constant 1/n=0.70, 0.62 and 0.55 and sorption capacities C_m=10.8 mmol^. g^-1, 6.1 mmol^. g^-1and 4.4 mmol^. g^-1, respectively, decreased with increasing temperature. Similarly, the sorption capacities of D-R isotherm X_m=197.6 μmol^. g^-1, 201.2 μmol^. g^-1and 137.4 μmol^. g^-1, also decreased with temperature. However, the sorption free energy E=10.2 kJ^. mol^-1, 11.2 kJ^. mol^-1and 12.7 kJ^. mol^-1, increased with temperature. The monolayer coverage (Q) computed from Langmuir isotherm was 11.1±0.6 μmol^. g^-1and remains constant at all the three temperatures investigated. However, the binding energy constant bincreased with temperature. The relationship of bwith temperature and differential heat of adsorption (ΔH_diff) have been evaluated and discussed.     

杂多酸盐K7[PTi2W10O40]·6H2O与牛血清白蛋白相互作用的研究

Under the imitated physiological condition of animal body, the interactions of heteropoly salt (PM-19) with bovine serum albumin (BSA) were investigated by fluorescence and absorption spectroscopy. It was shown that this compound had a quite strong ability to quench the fluorescence launching from BSA. After analyzing the fluorescence quenching data according to Stern-Volmer equation and Lineweaver-Burk double-reciprocal equation, we found that BSA had reacted with PM-19 and formed a certain new compound. The quenching belonged to static fluorescence quenching. According to Lineweaver-Burk equation, the forming constants of the compound (298 K: 2.68 × 10⁵ L·mol^-1; 304 K: 2.19 × 10⁵ L·mol^-1; 310 K: 1.82 × 105 L·mol^-1) and the thermodynamic parameters (ΔH=-24.72 kJ·mol^-1; ΔS=20.97 J·mol^-1·K^-1 / 20.92 J·mol^-1·K^-1/ 20.97 J·mol^-1·K^-1; ΔG=-30.97 kJ·mol^-1/ -31.08 kJ·mol^-1/-31.22kJ·mol^-1) at the corresponding temperatures were obtained. The latter shows that binding power between them is mainly electrostatic interaction. Based on F?rster′s non-radiation energy transfer mechanism, the binding locality (r=4.14 nm) was calculated between donor and accepter. The effect of PM-19 on the conformation of BSA was also analyzed by synchronous fluorescence spectroscopy.     

Lu(Et2dtc)3(phen)的生成反应焓变、摩尔热容和恒容燃烧能测定

A ternary solid complex Lu(Et₂dtc)₃(phen) has been obtained from the reaction of hydrated lutetium chloride with sodium diethyldithiocarbamate (NaEt₂dtc), and 1,10-phenanthroline (o-phen·H₂O) in absolute ethanol. IR spectrum of the complex indicates that Lu³⁺ binds with sulfur atom in the Na(Et₂dtc)₃ and nitrogen atom in the o-phen. The enthalpy change of liquid-phase reaction of formation of the complex, Δ_rH_m^Ө (l), was determined to be (-32.821 ± 0.147 ) kJ·mol^-1 at 298.15 K by an RD-496 Ⅲ type heat conduction microcalormeter. The enthalpy change of the solid-phase reaction of formation of the complex, Δ_rH_m^Ө (s), was calculated to be (104.160 ± 0.168) kJ · mol^-1 on the basis of an appropriate thermochemistry cycle. The thermodynamics of liquid-phase reaction of formation of the complex was investigated by changing the temperature of liquid-phase reaction. Fundamental parameters, such as the activation enthalpy (ΔH_≠^Ө), the activation entropy (ΔS_≠^Ө), the activation free energy (ΔG_≠^Ө), the apparent reaction rate constant (k), the apparent activation energy (E), the pre-exponential constant (A) and the reaction order (n), were obtained by combination the reaction thermodynamic and kinetic equations with the data of thermokinetic experiments. The molar heat capacity of the complex, c_m, was determined to be (82.23 ± 1.47) J·mol^-1·K^-1 by the same microcalormeter. The constant-volume combustion energy of the complex, Δ_cU, was determined as (-17 898.228 ± 8.59) kJ·mol^-1 by an RBC-Ⅱtype rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, Δ_cH_m^Ө, and standard enthalpy of formation, Δ_fH_m^Ө, were calculated to be (-17 917.43 ± 8.11) kJ·mol^-1 and (-859.95 ±10.12) kJ·mol^-1, respectively.     

Cu(Ⅱ)-牛磺酸缩水杨醛席夫碱-邻菲咯林三元配合物的合成、晶体结构及性质

The title complex was synthesized by reaction of taurine salicylic schiff base(TSSB), O-phenanthroline(phen) and cupric acetate in water-ethanol solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 498.00. The crystal structure of the title complex belongs to orthorhombic system with space group Pbcn and cell parameters: a=3.107 2(4) nm, b=1.289 09(18) nm, c= 1.034 78(14) nm; and V=4.144 7(10) nm³, Z=8, D_c=1.596 g·cm^-3, μ=1.197 mm^-1, F(000)=2 048. The compound is an one-dimensional chain complex of infinite length which are connected with hydrogen bonds. The Cu(Ⅱ) was coordinated by two oxygen atoms and three nitrogen while the o atoms of Ac- groups did not participate in the coordination. The Cu(Ⅱ) formed a distorted tetragonal pyramid and the capacities of coordination to Cu(Ⅱ) of atoms was discussed. Besides, the TG-IR of the complex was analyzed. The kinetics of the thermal decomposition reaction of the complex was studied under a non isothermal condition by TG-IR. TG and DTG curves indicate that the complex decomposed in three stages: (?) The kinetic parameters were obtained from the analysis of TG,DTG cures by OZAWA-Flynn-Wall method, and the activation energy and the value of A of the three stages are 74.98 kJ·mol^-1, 286.65 kJ·mol^-1, 87.55 kJ·mol^-1; 9.66×10⁸ s^-1,1.82×10²⁸ s^-1, 3.09×10³s^-1, respectively.     

L-苏糖酸锰的制备及标准生成焓

The pink powder of manganese L-threonate was obtained by extracting with alcohol the concentrated solution derived from the reaction between L-threonic acid solution prepared by double decomposition reaction of calcium L-threonate with oxalic acid and superfluous manganese oxide at 80℃ for certain time. The composition of the new compound was determined by chemical and elemental analyses and its formula fits Mn(C₄H₇O₅)₂·H₂O, the IR spectra indicated that Mn²⁺ in the compound coordinates to oxygen atom of the carboxyl group, while the proton of the carboxyl group is dissociated, it was assumed that the coordination number of Mn²⁺ was 4. The results of TG-DTG showed that the compound have fairish stability, the intermediate and final product of the thermal de-composition of the compound are Mn(C₄H₇O₅)₂ and MnO₂, respectively. The constant volume combustion energy of the compound, Δ_cE, were determined by a precise rotating-bomb calorimeter at 298.15K, it was (-3384.30±1.21)kJ·mol^-1, its standard enthalpy of Combustion,Δ_cH_m^?,and standard enthalpy of formation,Δ_fH_m^? , were calculated. They are (-3383.07±1.21)kJ·mol^-1 and (-2 571.68±1.63)kJ·mol^-1, respectively.     

MULTIDENTATE LIGAND EXCHANGE KINETICS:REACTIONS OF AMINOCARBOXYLATO-FERRATE(Ⅲ) COMPLEXES WITH 4-(2-PYRIDYLAZO) RESORCINOL

The kinetics and mechanism of ligand substitution reactions of nitnlotriacetatoiron(Ⅲ),(Fe(NTA)],and N-(2-hydroxycthyl)-ethylencdiaminetriacetatoiron(Ⅲ),[Fe(HEDTA)],complexes with 4-(2-pyridylazo) resorcinol (Par) has been investigated at pH=9.0±0.02,I=0.1mol·l^-1 (NaClO₄,and temp.=25±0.1℃ and 30±0.1℃ respectively. The reaction has been studied spectrophotometrically at 496 nm. (λmax of Fe(Par)₂. In both reactions the final product was [Fe(Par)₂]^-. The values of second order rate constants for NTA and HEDTA exchange reactions are (10.0±0.8)×10¹¹·mol^-1·s^-1 and (2.7±0.1)×10^-1·mol^-1·s_-1 respectively. The reactions of NTA and HEDTA exchange were studied in the pH range 6-9.5 and 7-10.85 respectively. The rate of reacton of [Fe(NTA)] with HPar^- first increases with pH and then levels off. However,in the case of [Fe(HEDTA)] reaction,the rate increases monotonically with increase of pH in the specified range.     

钐-邻硝基苯甲酸与1，10-邻菲咯啉配合物的热分解动力学

The complex of Sm₂(o-NBA)₆(PHEN)₂ (o-NBA, o-Nitrobenzoate; PHEN, 1,10-phenanthroline) was prepar-ed and characterized by elemental analysis, IR and UV spectraoscopy. The thermal decomposition mechanism of Sm₂(o-NBA)₆(PHEN)₂ was studied under a static air atmosphere by TG-DTG. The thermal decomposition kinetics of the complex for the first stage was studied under non-isothermal condition. The most probable mechanism functions of the thermal decomposition reaction for the first stage are: G(α)=[-ln(1-α)]^1/2, f(α)=2(1-α)[-ln(1-α)]^1/2. The activation energy E for the first stage is 259.50 kJ·mol^-1, the pre-exponential factor A is 36.19×10¹⁸ min^-1. The lifetime equation at weight-loss of 10% was deduced as lnτ=-36.70+27 572.12/T by isothermal thermogravimetric analysis.     

CH2(COO)2Cu·2H2O热分解的非等温动力学研究

The thermal dehydration and decomposition kinetics of CH₂(COO)₂Cu·2H₂O were investigated using the non-isothermal method by thermogravimetry (TG) technique in N₂. The iterative iso-conversional methods were applied to calculate the activation energy E_a of dehydration and decomposition， and the most probable mechanism function G(α) was determined by means of the master plots method. The pre-exponential factor A was obtained on the basis of E_a and G(α). Kinetic parameters (E_a and lnA) of dehydration were given as: E_a=139.79 kJ·mol^-1， ln(A/s^-1)=47.38. The mechanism function of the dehydration was G(α)=[-ln(1-α)]^2/3， and the decomposition of CH₂(COO)₂Cu proceeds to completion by two distinct reactions. These two reactions overlap in the transition process (0.45<α<0.65). Kinetic parameters (E_a and lnA )of the first reaction of decomposition were: E_a=201.15 kJ·mol^-1， ln(A/s^-1)=52.29， and the mechanism function was G(α)=[1-α]^-0.37. And in the second reaction G(α)=α+(1-α)ln(1-α)， E_a=156.74 kJ·mol^-1， ln(A/s^-1)=39.58.     

锆-氘反应热力学特性研究

The p-c-T curves and the relation between equilibrium pressure and temperature of deuterium absorption and desorption from zirconium were measured in the temperature range of 400～675 ℃. Equilibrium pressure of the absorption and desorption at different temperatures were given and then the thermodynamic parameters and the deuterium absorption capacity were determined according to Vant Hoff equation. There are different changes of enthalpy and entropy when zirconium changes to different phases. The change of enthalpy in the phase of α plus δ is -98.9 kJ·mol^-1 in the temperature range of 400～475 ℃. The changes of enthalpy in the first and second plateau are -75.1 kJ·mol^-1 and -161.7 kJ·mol^-1, respectively in the temperature range of 525～675 ℃. The corresponding changes of entropy are -66.5 J·K^-1·mol^-1, -32.4 J·K^-1·mol^-1 and -146.5 J·K^-1·mol^-1, respectively. There are obvious lagging effects when zirconium desorbs deuterium.     

新生态二氧化锰的性质及pH值影响除砷效果的研究

Fresh MnO₂ was prepared by oxide reduction using KMnO₄ and MnSO₄. The structure and property of the products were characterized by TEM, SEM, XRD and BET, and the effect of pH value was studied on the removal of both As(Ⅴ) and As(Ⅲ). The results show that δ-MnO₂ is spherical, its specific surface is 325 m²·g^-1 with lots of hydroxyl on the surface. Adsorption of fresh MnO₂ of As(Ⅲ) was a corporate action of both oxide reaction and electrostatic adsorption, but the adsorption of As(Ⅴ) was due to electrostatic and anion exchange adsorption.     

水合偏硼酸钾的热化学研究

Hydrated potassium monoborate(KBO₂·4/3H₂O) was obtained from an aqueous solution in a mole ratio of K₂O∶B₂O₃=2∶1 and characterized by powder X-ray diffraction(XRD)， infrared spectroscopy(FT-IR) and Raman spectroscopy. The enthalpy of solution of hydrated potassium monoborate， KBO₂·4/3H₂O， in approximately 1mol·dm^-3 aqueous hydrochloric acid was determined. Together with the previously determined enthalpies of so-lution of H₃BO₃ in approximately 1mol·dm^-3 HCl(aq) ，and of KCl in aqueous(hydrochloric acid+boric acid)， the standard molar enthalpy of formation of -(1411.11±0.84)kJ·mol^-1 for KBO₂·4/3H₂O was obtained from the standard molar enthalpies of formation of KCl(s)， H₃BO₃(s)， and H₂O(l). The standard molar entropy of formation of -422.94J·K^-1·mol^-1 and standard molar entropy of 163.47J·K^-1·mol^-1 for KBO₂·4/3H₂O were calculated from the thermodynamic relations. A group contribution method is applicable to KBO₂·4/3H₂O.     

配合物[Mn(bipy)3](ClO4)2的晶体结构和热分析研究

The complex [Mn(bipy)₃]·(ClO₄)₂ was synthesied and characterized by X-ray diffraction. X-ray diffraction result for the single crystal showed that the crystal belongs to triclinic, space group P1, a=0.8123(2),b=1.1024(2), c=1.8646(4)nm,α=102.30(3)°,β=91.00(3)°,γ=99.69(3)°,V=1.6056(6)nm³,Z=2,D_c=1.494g·cm^-3. The thermal decomposition of [Mn(bipy)₃](ClO₄)₂ occurred in a three steps pattern. The reaction mechanism of the first step decomposition was deduced as n(1-α)[-ln(1-α)](n-1)/n with the activation energy of 130kJ·mol^-1.     

壳聚糖/Pb(Ⅱ)模板壳聚糖膜与Pb(Ⅱ)螯合反应的动力学及机理探讨

Chitosan and chitosan membranes with Pb(Ⅱ) ion as template were studied. The adsorption isotherms were correlated by dc/dt=-kcⁿ at the temperature of 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃. By means of linear correlation, the shapes of the isotherm curves were similar to the kinetic function of 2/c^1/2=-kt and the apparent activation energy for with chitosan(123.8 kJ·moL^-1) was larger than that of membrane with Pb(Ⅱ) ion(92.3kJ·moL^-1). The chitosan membrane with Pb(Ⅱ) ion template was better “memory” function. The adsorption mechanism of chitosan with Pb(Ⅱ) was studied by IR and XPS. The results indicated that the nitrogen in -NH₂ and the oxygen in C₃-OH of chitosan were coordination atoms.     

牛血清白蛋白与两种金属配合物的作用研究

The interaction of Methylthymol Blue(MTB)-Zinc(Ⅱ) compound and Alizarin Red S(ARS)-Aluminum(Ⅲ) compound with Bovine serum albumin (BSA) was investigated by UV-Vis spectrophotometric method in acidic buffer solution. MTB-Zn(Ⅱ)-BSA was a blue color compound, which possesses maximum absorption at 613 nm with 172 nm, 174 nm and 18 nm of red shift compared to the MTB, MTB-BSA and MTB-Zn(Ⅱ) complexes respectively. Dual wavelength substantial amount ratio method, balance dialysis substantial amount ratio method and unity wavelength substantial amount ratio method were compared. The following results were obtained: the apparent molar absorptivity of MTB-Zn(Ⅱ) with BSA was ε=2.20×10⁴ L·mol^-1·cm^-1. Conditional proportion were defined, n_MTB∶n_Zn(Ⅱ)∶n_BSA=2∶2∶1; condition combination constant, K=2.07×1010. Combination proportion were defined, n_ARS∶n_Al(Ⅲ)∶n_BSA=6∶4∶1. Condition equilibrium constant of reaction of ARS-Al(Ⅲ) with BSA was K=8.80×10⁸. The apparent molar absorptivity of ε=2.65×10⁴ L·mol^-1·cm^-1. It is suggested that combination between BSA and MTB-Zn(Ⅲ) is due to coordination force. That combination between BSA and ARS-Al(Ⅲ) is due to the coordination bond and electrostatic force.     

高岭石无定形化的动力学研究

Amorphous kaolinite derivatives were prepared through mixing kaolinite with HCOOK and KOH solution. Ki-netics of kaolinite being turned into amorphous derivatvies was investigated by XRD. It showed that the transfor-mation included dynamic and diffuse controlling stages. And the active energy E₁=26.8kJ·mol^-1; E₂=12.2 kJ·mol^-1. TEM and SEM images showed that particle size of the amorphous derivatives was about 50nm. And the amorphous derivatives seemed like alumnsilicate gel， accompanied by some aggregates.     

CsCl-TmCl3-HCl-H2O(25 ℃)的相平衡及其固相化合物

The equilibrium solubilities of the quaternary system CsCl-TmCl₃-HCl-H₂O was determined at 25 ℃ and the corresponding equilibrium diagram was constructed. The diagram is a complicated system with limited solid solutions and formation of a new compound 3CsCl·2TmCl₃·14H₂O. The new compound has been characterized by XRD, TC-DTG and fluorescence spectrometry. Results show that upconversion spectrum exhibits at 335 nm when exciting at 860 nm, and fluorescence spectrum exhibits at 295 nm and 385 nm when exciting at 240 nm. The compound loses its crystal water by four steps at 50 to 250 ℃. Using a heat conduction calorimeter, the standard molar enthalpy of dissolution of 3CsCl·2TmCl₃·14H₂O was determined to be (-11.601 ± 0.050) kJ·mol^-1 at 298.15 K.     

微乳液--1-(2-吡啶偶氮)-2-萘酚体系测定Co(Ⅱ)

The spectrohpotometric determination of Co(Ⅱ) was studied with 1-( 2 -pyridylazo)-2-naphthol in the sodium dodecyl sulphate/n-heptane/water micr oemulsion medium.The apparent molar absorptivity is 1.84×10⁴ L^.mol -1^.cm^-1 at 575 nm.Beer's law is obeyed in the range of 0～ 50 μg/25 mL for Co(Ⅱ).     

钴配合物的合成晶体结构及活性研究

The complex [Co₂Cl₂(EGTB)]·(ClO₄)₂·5H₂O was synthesized in methanol-aqueous solution and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic with space group of P2₁/c. The cell parameters are a=1.42231(2)nm,b=2.53181(3)nm,c=1.43392(2)nm,β=102.0518(5)°, Z=4, F(000)=2360,D_c=1.508g·cm^-3, The final R=0.0788,wR₂=0.232, The catalytic rate constant of the dismutation of superoxide radicals has been obtained by means of photo reduction of nitroblue tetrazolium(NBT),and it is 1.875×10⁶mol^-1·L·s^-1.