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101.
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, ΔrHmӨ (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, ΔrHmӨ (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 (ΔHӨ), the activation entropy (ΔSӨ), the activation free energy (ΔGӨ), 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, cm, 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, ΔcU, 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, ΔcHmӨ, and standard enthalpy of formation, ΔfHmӨ, were calculated to be (-17 917.43 ± 8.11) kJ·mol-1 and (-859.95 ±10.12) kJ·mol-1, respectively.  相似文献   
102.
在无水乙醇中, 使低水合氯化稀土 (RE = Ho, Er, Tm, Yb, Lu) 与吡咯烷二硫代氨基甲酸铵 (APDC)和1,10-菲咯啉 (o–phen•H2O) 反应, 制得其三元固态配合物. 用化学分析和元素分析确定它的组成为RE(C5H8NS2)3(C12H8N2) (RE = Ho, Er, Tm, Yb, Lu). IR光谱说明RE3+ 分别与3个PDC的6个硫原子双齿配位, 同时与o–phen的2个氮原子双齿配位, 配位数为8. 用精密转动弹热量计测定了它们的恒容燃烧热△cU分别为(-16788.46 ± 7.74), (-15434.53 ± 8.28), (-15287.80 ± 7.31), (-15200.50 ± 7.22)和(-15254.34 ± 6.61) kJ•mol-1; 并计算了它们的标准摩尔燃烧焓△cHmθ和标准摩尔生成焓△fHmθ分别为( -16803.95 ± 7.74), (-15450.02 ± 8.28), (-15303.29 ± 9.28), (-15215.99 ± 7.22), (-15269.83 ± 6.61) kJ • mol-1和 (-1115.42 ± 8.94), (-2477.80 ± 9.15), (-2619.95 ± 10.44), (-2670.17 ± 8.22), (-2650.06 ± 8.49) kJ•mol-1.  相似文献   
103.
L-苏糖酸锰的制备及标准生成焓   总被引:1,自引:0,他引:1  
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, ΔcE, 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,ΔcHm?,and standard enthalpy of formation,ΔfHm? , were calculated. They are (-3383.07±1.21)kJ·mol-1 and (-2 571.68±1.63)kJ·mol-1, respectively.  相似文献   
104.
稀土氨基酸配合物具有消炎、杀菌、降血糖等作用犤1犦。它们的晶体结构和相化学已有报道犤2,3犦。前报犤4犦曾详细报道了稀土硝酸盐与组氨酸配合行为的溶解度图和制备与表征。但文献中未见有关该类配合反应热动力学研究的报道。本文用微量热法对硝酸钐/硝酸镝/硝酸铒与组氨酸的液-液反应进行了热动力学研究。其结果可为这类配合物的反应机理研究和制备提供必要的技术参数。1实验部分1.1试剂RE(NO3)3·6H2O(RE=Sm,Dy,Er)按文献犤5犦的方法制备。L-α-组氨酸为B.R.(上海康达氨基酸厂);纯度>99.5%…  相似文献   
105.
Ten solid complexes of zinc nitrate with L-α-leucine(Leu), L-α-valine(Val), L-α-tryptophan(Try) and L-α-threonine(Thr) were prepared in water. The compositions of these complexes are determined by chemical analysis and elemental analysis, which are identified as Zn(Leu)(NO3)2·2H2O(A), Zn(Leu)2(NO3)2·H2O(B), Zn(Val)(NO3)2·2H2O(C), Zn(Val)2(NO3)2·H2O(D), Zn(Val)3(NO3)2·H2O(E), Zn(Try)(NO3)2·2H2O(F), Zn(Try)2(NO3)2·H2O(G), Zn(Thr)(NO3)2·2H2O(H), Zn(Thr)2(NO3)2·H2O(I) and Zn(Thr)3(NO3)·H2O(J). The constant-volume combustion energies of the complexes, ΔcU(complex), were determined by a precise rotating bomb calorimeter at 298.15K. Standard enthalpies of combustion,ΔcHm?(complex, s, 298.15K), and standard enthalpies of formation, ΔfHm?(complex,s,298.15K) for these complexes were calculated as (4523.22±2.08), (7208.86±4.28), (3442.21±1.85), (5971.21±3.32), (9007.26±4.24), (5802.35±2.14), (10891.58±3.01), (2147.40±1.28), (4120.83±0.99), (6444.68±3.85)kJ·mol-1 and (615.67±2.27), (1863.16±4.60), (1017.34±2.00), (1742.93±3.61), (2245.70±4.73), (1161.18±2.61), (1829.71±4.20), (1632.82±1.43), (1885.55±1.50), (2770.25±4.21)kJ·mol-1, respectively.  相似文献   
106.
确定了Zn(Val)SO4·H2O在水-丙酮中结晶生长的最佳体积比为1:10,用微量热法测定了该结晶生长过程在298.15K时的放热量及产热速率,计算了动力学常数,认为结晶过程符合Burton-Cabrera-Frank位错理论.同时测定了Zn(Val)SO4·H2O于298.15K时在纯水中的溶解焓为(28.46±0.08)kJ·mol-1,计算了Zn(Val)2+(aq)的标准生成焓为(-569.71±3.84)kJ·mol-1.  相似文献   
107.
硫酸锌与组氨酸固液反应的热动力学研究   总被引:6,自引:0,他引:6  
用微热量计对硫酸锌与组氨酸在水中的固液反应进行了热动力学研究。通过实验和计算得出了该反应的热动力学参数(活化焓,活化熵及活化自由能),速率常数和动力学参数(活化能,指前因子及反应级数),并对温度改变对该反应的影响及配合物的合成条件进行了讨论。  相似文献   
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