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A double-development TLC method has been developed for simultaneous qualitative and quantitative analysis of hydrophilic and lipophilic constituents of Salvia miltiorrhiza (Danshen). The optimized mobile phases dichloromethane-ethyl acetate-formic acid 22:24:10 (ν/ν) and petroleum ether-ethyl acetate-cyclohexane 25:11:14 (ν/ν) were used for the double development on nano-silica gel 60F254 plates. Their characteristic TLC profiles were observed under UV light at 254 and 365 nm and the bands were then revealed by reaction with 5% H2SO4 in EtOH. Quantification of twelve compounds was achieved by densitometry at 260 or 290 nm, with reference at 400 nm. Linearity was quite good (R 2 > 0.99) within the ranges tested. This method could be used for quality control of Danshen.

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Journal of Thermal Analysis and Calorimetry
Authors:
L. Xu
,
Y. De-Jun
,
L. Qiang-Guo
,
L. Ai-Tao
,
Y. Li-Juan
,
J. Qian-Hong
, and
L. Yi

Abstract  

The product from reaction of samarium chloride hexahydrate with salicylic acid and Thioproline, [Sm(C7H5O3)2·(C4H6NO2S)]·2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, and thermogravimetric analysis. The standard molar enthalpies of solution of [SmCl3·6H2O(s)], [2C7H6O3(s)], [C4H7NO2S(s)] and [Sm(C7H5O3)2·(C4H7NO2S)·H2O(s)] in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide(DMSO) and 3 mol L−1 HCl were determined by calorimetry to be Δs H m Φ[SmCl3 δ6H2O (s), 298.15 K]= −46.68±0.15 kJ mol−1 Δs H m Φ[2C7H6O3 (s), 298.15 K]= 25.19±0.02 kJ mol−1, Δs H m Φ[C4H7NO2S (s), 298.15 K]=16.20±0.17 kJ mol−1 and Δs H m Φ[Sm(C7H5O3)2·(C4H6NO2S)]·2H2O (s), 298.15 K]= −81.24±0.67 kJ mol−1. The enthalpy change of the reaction

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$SmCl_3 \cdot 6H_2 O(s) + 2C_7 H_6 O_3 (s) + C_4 H_7 NO_2 S(s) = Sm(C_7 H_5 O_3 )_2 \cdot (C_4 H_6 NO_2 S) \cdot 2H_2 O(s) + 3HCl(g) + 4H_2 O(1)$$ \end{document}
((1)) was determined to be Δs H m Φ =123.45±0.71 kJ mol−1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of Sm(C7H5O3)2(C4H6NO2S)δ2H2O(s) was estimated to be Δs H m Φ[Sm(C7H5O3)2·(C4H6NO2S)]·2H2O(s), 298.15 K]= −2912.03±3.10 kJ mol−1.

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Abstract  

The complex from reaction of neodymium chloride six-hydrate with salicylic acid and 8-hydroxyquinoline, Nd(C7H5O3)2·(C9H6NO), was synthesized and characterized by IR, elemental analysis, molar conductance, and thermogravimatric analysis. The standard molar enthalpies of solution of [NdCl3·6H2O(s)], [2C7H6O3(s)], [C9H7NO(s)] and [Nd(C7H5O3)2·(C9H6NO)(s)] in a mixed solvent of anhydrous ethanol, dimethyl formamide (DMF) and perchloric acid were determined by calorimetry at 298.15 K. Based on Hess’ law, a new chemical cycle was designed, and the enthalpy change of the reaction

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$NdCl_3 \cdot 6H_2 O(s) + 2C_7 H_6 O_3 (s) + C_9 H_7 NO(s) = Nd(C_7 H_5 O_3 )_2 \cdot (C_9 H_6 NO)(s) + 3HCl(g) + 6H_2 O(l)$$ \end{document}
((1)) was determined to be Δr H m Θ=117.89±0.37 kJ mol−1. From data in the literature, through Hess’ law, the standard molar enthalpy of formation of Nd(C7H5O3)2·(C9H7NO)(s) was estimated to be Δf H m Θ[Nd(C7H5O3)2·(C9H6NO)(s), 298.15 K]=−2031.80±8.6 kJ mol−1.

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