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In this work, the binding interaction between a new bismuth(III) Schiff base complex |[Bi(valen)]Cl·2H2O}[H2 valen=N,N'-bis(2-hydroxy-3-methoxyphenylmethylidene)-2,6-pyridinediamine, C21H19N3O4] and bovine serum albumin(BSA) was studied via fluorescence quenching method. The static quenching constant K LB and some thermodynamic parameters(e.g., ΔG θ, ΔH θ and ΔS θ) of the interaction were estimated. In particular, the binding site between the complex and BSA was explored by molecular docking. On the basis of the mechanism of Forster energy transfer, the binding distance between the bismuth(III) Schiff base complex and BSA(Trp.213) as well as the transfer efficiency was obtained. Furthermore, the effect of the bismuth(III) Schiff base complex on the con-formation of BSA was investigated using synchronous fluorescence spectroscopy.

A mononuclear salen-type complex [Cu( vanen )(H 2 O)] was synthesized from the ligand [H 2 vanen = N , N - ethylene-bis(3-methoxysalicylideneimine)] and Cu(OAc) 2 ·H 2 O. Based on Hess law, a reasonable thermochemical cycle was designed. According to the cycle, the standard molar enthalpies of dissolution of samples in the calorimetric solvent of DMF ( N , N -dimethylformamide) were determined, respectively. The standard molar enthalpy change of the coordination reaction (Δ r H m θ ) was calculated to be -(16.61 ± 0.54) kJ/mol. Combined with some relevant literature data, the standard molar enthalpy of formation (Δ f H m θ ) of the complex was obtained to be -(756.5 ± 2.4) kJ/mol. At the temperature of 32 ℃, the metabolic thermogenetic curves of S. pombe under the influence of the complex with different concentration were determined by using a TAM air isothermal calorimeter. The relationships of the concentration of the complex with the microbial growth rate constant ( k ) of S. pombe , inhibition ratio (I), the half inhibition concentration (IC 50 ), the maximum heat output power ( P max ) and the time it took ( t max ) were analyzed. The results indicated that the complex possessed the Hormesis effect, which promoted the growth of S. pombe at lower concentration, but inhibited the growth at higher concentration.

采用均匀沉淀法，在20%的乙醇水溶液中，用水杨酸、维生素B3与稀土硝酸盐合成了一类新的稀土三元配合物. 通过元素分析、化学分析、摩尔电导、红外光谱、紫外光谱、热重-微分热重分析等手段对配合物的结构和性质进行表征，确定了它们的组成通式为[RE（C 7 H 5 O 3 ） 2 （C 6 H 4 NO 2 ）·H 2 O] （RE = La，Ce，Nd）. 维生素B3吡啶环上的N原子和水杨酸的酚羟基均未参与配位，两种配体均是脱质子后以羧酸根与RE 3+ 离子配位，且成键以离子性为主，兼有部分共价性. 在298.15 K，用精密的溶解-反应热量计分别测量了配位反应相关各物质的溶解焓，根据盖斯（Hess）定律求得合成反应的标准摩尔反应焓Δ r H m θ 分别为： （180.61 ± 0.72）、（187.25 ± 0.68）和（185.61 ± 0.26）kJ/mol. 进而求出配合物的标准摩尔生成焓为：Δ f H m θ [La（C 7 H 5 O 3 ） 2 （C 6 H 4 NO 2 ）·H 2 O（s），298.15 K] = -（2493.9 ± 2.9）、Δ f H m θ [Ce（C 7 H 5 O 3 ） 2 （C 6 H 4 NO 2 ）·H 2 O（s），298.15 K] = -（2441.0 ± 2.8）和 Δ f H m θ [Nd（C 7 H 5 O 3 ） 2 （C 6 H 4 NO 2 ）·H 2 O（s），298.15 K] = -（ 2463.1 ± 2.9）kJ/mol.

The reaction of cerium chloride heptahydrate with salicylic acid and thioproline produced [Ce(Hsal)2·(tch)]·2H2O [Hsal = salicylate (C7H5O3−), tch = thioprolinate (C4H6NO2S−))], which was isolated and characterized by IR, elemental, chemical, and thermogravimetric analysis. The standard molar enthalpies of solution of [CeCl3·7H2O(s)], [2C7H6O3(s)], [C4H7NO2S(s)], and [Ce(Hsal)2·(tch)·2H2O(s)] in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO), and 3 mol·L−1 HCl were determined by calorimetry to be ΔsHmΘ[CeCl3·7H2O(s), 298.15 K] = −(42.22 ± 0.37) kJ·mol−1, ΔsHmΘ[2C7H6O3(s), 298.15 K] = (45.54 ± 0.37) kJ·mol−1, ΔsHmΘ[C4H7NSO2(s), 298.15 K] = (21.91 ± 0.60) kJ·mol−1, and ΔsHmΘ[Ce(Hsal)2·(tch)·2H2O(s), 298.15 K] = −(30.87 ± 0.39) kJ·mol−1. The enthalpy change of the reaction CeCl3·7H2O(s) + 2C7H6O3(s) + C4H7NO2S(s) = [Ce(Hsal)2·(tch)]·2H2O(s) + 3HCl(g) + 5H2O(l) was determined to be ΔrHmΘ = (263.12 ± 0.95) kJ·mol−1. From data in the literature, through Hess’s law, the standard molar entha...

A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution enthalpies of SmCl3·6H2O(s), o-HNBA(s) and phen·H2O(s) in mixed solvent (VHCl :VDMF:VDMSO=2:2:1) were determined by calorimetry at 298.15 K. The enthalpy change of the reaction was determined to be ΔrHθm=252.49±1.60 kJ/mol. Using the relevant data in the literature and a thermochemical recycle according to Hess's Law, the standard molar enthalpy of formation of [Sm(o-NBA)3 phen]2 (s) was estimated to ΔfHθm=−4109.2±7.3 kJ/mol.

The product from the reaction of neodymium chloride hexahydrate with salicylic acid and thioproline, [Nd(Hsal) 2 ·(tch)]·2H 2 O, was synthesized and characterized by IR, elemental analysis, molar conductance, thermogravimetric analysis, and chemical analysis. The standard molar enthalpies of solution of NdCl 3 ·6H 2 O(s), [2C 7 H 6 O 3 (s)], C 4 H 7 NO 2 S(s), and [Nd(Hsal)2·(tch)]·2H 2 O(s) in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO), and 3 mol·L ―1 HCl were determined by calorimetry to be Δ s H Θ m [NdCl 3 ·6H 2 O(s), 298.15 K] = ―(51.94 ± 0.14) kJ·mol ―1 , Δ s H Θ m [2C 7 H 6 O 3 (s), 298.15 K] = (52.96 ± 0.48) kJ·mol ―1 , Δ s H Θ m [C 4 H 7 NO 2 S(s), 298.15 K] = (23.50 ± 0.23) kJ·mol ―1 , and Δ s H Θ m {[Nd(Hsal) 2 · (tch)]·2H 2 O(s), 298.15 K} = ―(41.76 ± 0.50) kJ·mol ―1 . The enthalpy change of the reaction NdCl 3 ·6H 2 O(s) + 2C 7 H 6 O 3 (s) + C 4 H 7 NO 2 S(s) = [Nd(Hsal) 2 ·(tch)]·2H 2 O(s) + 3HCl(g) + 4H 2 O(l) was determined to be Δ r H Θ m = (172.57 ± 0.75) kJ·mol ―1 . From data in the literature, through Hess' law, the standard molar enthalpy of formation of [Nd(Hsal) 2 ·(tch)]·2H 2 O(s) was estimated to be Δ f H Θ m {[Nd(Hsal) 2 ·(tch)]·2H 2 O(S), 298.15 K} = -(2867.1 ± 8.6) kJ·mol ―1 .