As a new form of traditional Chinese medicine (TCM), Zuojin pill extract is made containing Coptidis rhizoma (the rhizome of Coptis chinesis Franch. [Ranunculaceae]) and Euodiae fructus (the unripe fruit of Euodia rutaecarpa [Juss.] Benth. [Rutaceae]) at the ratio of 6:1 (w/w) and has been most widely used in TCM to treat gastro-intestinal disorders. However, the quality control is insufficient. For establishing an analysis method for the effective quality control of Zuojin pill extract, the active components of three protoberberine alkaloids (coptisine, palmatine, berberine, components from C. rhizoma) and two indolequinoline alkaloids (evodiamine, rutaecarpine, components from E. fructus) in Zuojin pill extract were determined simultaneously by high-performance liquid chromatography. Chromatographic separations were performed on an Inertsil ODS-3 column (4.6 mm × 250 mm, 5 μm). Elution was carried out at 25°C under isocratic conditions by using 25 mmol L−1 KH2PO4-25 mmol L−1 SDS-acetonitrile (1:1:2, v/v/v, adjusted pH to 3.0 using phosphoric acid) as a mobile phase with a flow rate of 0.5 mL min−1. Detection wavelength was set at 264 nm. Good linearity was obtained with correlation coefficient higher than 0.999 for all the analytes over the investigated concentration ranges. Three batches of Zuojin pill extract were successfully analyzed. The average percentages of coptisine, palmatine, berberine, evodiamine, and rutaecarpine in Zuojin pill extract were 5.35%, 3.92%, 16.64%, 0.03%, and 0.03%, respectively. Consequently, these protoberberine and indolequinoline alkaloids could be identified and determined easily by the established high-performance liquid chromatography (HPLC) method which can be used to evaluate and control the quality of Zuojin pill extract.
Effects of nano-metal powders (aluminum and nickel) addition on the thermooxidative degradation of binder PEG in air atmosphere
from 20 to 350°C were studied by TG/DTA and in-situ FTIR. TG/DTA results showed that the addition of nano-Al slowed down the
degradation process of PEG in the early period but accelerated the process in the late period; the addition of nano-Ni made
the PEG degradation process begin as soon as melted. The in-situ FTIR results showed that nano-Ni promoted the thermooxidative
degradation of PEG in air, and made the degradation process of PEG complete much earlier.
Authors:L. Liu, T. Zhao, X. M. Cheng, C. H. Wang, and Z. T. Wang
Harmaline and harmine accounted for more than 70% in composition in extracts of P. harmala. More attention, however, should be paid to the other alkaloids which would be favorable or unfavorable to the efficacy and safety of the products. It was necessary to determine these trace alkaloids in the extracts; thereafter, most of them have been characterized. Diglycoside vasicine, vasicine, vasicinone, harmalol, harmol, tetrahydroharmine, 8-hydroxy-harmine, ruine, harmaline, and harmine were separated and identified with reference substances and characteristic MS spectra in extracts by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Three trace alkaloids, vasicine, harmalol, and harmol were determined using the developed chromatographic separation method subsequently. The average contents of vasicine, harmalol, and harmol in extracts of ten batches were 2.53 ± 0.73, 0.54 ± 0.19, and 0.077 ± 0.03%, respectively. The total content of the three alkaloids was 3.23 ± 0.90% (from 1.81 to 4.48%). For rough estimation of all the relative alkaloids except of harmaline and harmine, the average total areas of all peaks in extracts varied from 4.35 to 26.64% detected at 220, 254, 265, 280, and 380 nm, respectively. The results indicated that area normalization method was powerless for the quality evaluation for traditional herb medicine consisting of numerous compounds with highly differential features. It might be concluded that LC-MS or HPLC could be utilized as a qualitative and quantitative analytical method for quality control of the extracts from seeds of P. harmala L.
Authors:S. Wang, Z. Tan, Y. Di, F. Xu, M. Wang, L. Sun, and T. Zhang
As one primary component of Vitamin B3, nicotinic acid [pyridine 3-carboxylic acid] was synthesized, and calorimetric study and thermal analysis for this compound
were performed. The low-temperature heat capacity of nicotinic acid was measured with a precise automated adiabatic calorimeter
over the temperature rang from 79 to 368 K. No thermal anomaly or phase transition was observed in this temperature range.
A solid-to-solid transition at Ttrs=451.4 K, a solid-to-liquid transition at Tfus=509.1 K and a thermal decomposition at Td=538.8 K were found through the DSC and TG-DTG techniques. The molar enthalpies of these transitions were determined to be
ΔtrsHm=0.81 kJ mol-1, ΔfusHm=27.57 kJ mol-1 and ΔdHm=62.38 kJ mol-1, respectively, by the integrals of the peak areas of the DSC curves.
Authors:C. Li, C. Wang, X. Liu, Z. Zheng, L. Wang, Q. Zhu, M. Kang, T. Chen, and C. Liu
In terms of pre-safety assessment of a potential site for high-level radioactive wastes disposal in China, the geochemical
behavior of key radionuclides which tend to be released from the repository must be thoroughly investigated. 99Tc is a long-lived fission product with appreciable productivity in nuclear fuel, and Tc (+7) has unlimited solubility in
near-field geochemical environments. In this study, the effects of ionic strength and humic acid on 99TcO4− sorption and diffusion in Beishan granite were investigated with through-diffusion and batch sorption experiments. Results
indicated that the effective diffusion coefficients (De) of 99TcO4− in Beishan granite varied from 1.07 × 10−12 to 1.28 × 10−12 m2/s without change with ionic strength, while the distribution coefficients (Kd) negatively correlated with ionic strength of the rock/water system. This study also indicates that there is no evident influence
of humic acid concentration on the diffusion behavior of 99TcO4− in Beishan granite, due to the limited interaction between humic acid and 99TcO4−.
Authors:J. Li, W. Dai, G. Xiao, H. Wang, Z. Zhang, and T. Wu
99Tc is an important radionuclides related to repository safety assessment. The mobility pertechnetate (TcO4−) can be reduced to immobility technetium(IV) hydrous oxides (TcO2·nH2O) by Fe(II)-bearing minerals. In China, Gaomiaozi (GMZ) bentonite is regarded as the favorable candidate backfilling material
for the HLW repository, which is contained some FeO. The diffusion behavior of 99Tc was investigated in GMZ bentonite by through- and out-diffusion methods. The effective diffusion coefficient (De), the accessible porosity (εacc), apparent diffusion coefficient (Da) and distribution coefficient (Kd) were decreased with the increasing of dry density. The De values were (2.8 ± 0.2) × 10−11 m2/s and (3.5 ± 0.2) × 10−12 m2/s at dry density of 1,600 and 1,800 kg/m3, respectively. It was indicated that the dominating species was TcO4− during the diffusion processing. While, out-diffusion results showed that part of TcO4− may be reduced by Fe(II). The relationship of De and εacc could be described by Archie’s law with exponent n = 2.4 for 99Tc diffusion in GMZ bentonite. Furthermore, the relationship between Da and dry density (ρ) was exponential.
Authors:M.-H. Wang, Z.-C. Tan, Q. Shi, L.-X. Sun, and T. Zhang
heat capacities of 2-benzoylpyridine were measured with an automated adiabatic
calorimeter over the temperature range from 80 to 340 K. The melting point,
molar enthalpy, ΔfusHm,
and entropy, ΔfusSm,
of fusion of this compound were determined to be 316.49±0.04 K, 20.91±0.03
kJ mol–1 and 66.07±0.05 J mol–1
K–1, respectively. The purity of the compound
was calculated to be 99.60 mol% by using the fractional melting technique.
The thermodynamic functions (HT–H298.15) and (ST–S298.15) were calculated based
on the heat capacity measurements in the temperature range of 80–340
K with an interval of 5 K. The thermal properties of the compound were further
investigated by differential scanning calorimetry (DSC). From the DSC curve,
the temperature corresponding to the maximum evaporation rate, the molar enthalpy
and entropy of evaporation were determined to be 556.3±0.1 K, 51.3±0.2
kJ mol–1 and 92.2±0.4 J K–1
mol–1, respectively, under the experimental
Authors:C.L. Liu, X.Y. Wang, Z.M. Wang, S.S. Li, C.T. Xin, H.F. Wang, B. Li, and L. Jiang
The migration of 99Tc in a weak loess aquifer was investigated in-situ with undisturbed aquifer medium columns. The columns were obtained horizontally at a depth of 3236 m in an Underground Research Facility (URF). Quartz containing 3H (HTO) and 99Tc (in the form of 99TcO4-) was introduced into one end of the columns and the columns were covered tightly. Aquifer water was introduced into the columns directly from an experimental shaft in the UFR. Effluents from the columns were collected and the activity of 3H and 99Tc were determined with a liquid scintillation analyzer. The breakthrough curves of 3H and 99Tc indicate that 99Tc migrates a little faster than that 3H does in the aquifer.
Authors:X. Han, Y. Sun, T. Wang, Zh. Lin, Sh. Li, F. Zhao, Z. Liu, J. Yi, and X. Ren
The effects of fullerenes, including fellerene soot (FS), extracted fullerene soot (EFS) and pure C60 on the thermal decomposition of ammonium perchlorate (AP) compared with traditional carbon black (CB) catalyst has been studied
by employing thermogravimetry (TG), differential thermal analysis (DTA), infrared spectroscopy (IR) and ignition temperature
experiments. The results showed that the addition of CB and FS to AP reduced the activation energy as well as the temperature
at maximum decomposition rate, but that of EFS and pure C60 had little effect on the thermal decomposition of AP, and among all catalysts, FS was the best one.
Authors:Y. C. Xiao, L. T. Liu, J. J. Bian, C. Q. Yan, L. Ye, M. X. Zhao, Q. S. Huang, W. Wang, K. Liang, Z. F. Shi, and X. Ke
Shuganjieyu (SGJY) capsule is a classical formula widely used in Chinese clinical application. In this paper, an ultra-performance liquid chromatography coupled with electrospray ionization and ion trap mass spectrometry has been established to separate and identify the chemical constituents of SGJY and the multiple constituents of SGJY in rats. The chromatographic separation was performed on a C18 RRHD column (150 × 2.1 mm, 1.8 μm), while 0.1% formic acid–water and 0.1% formic acid–acetonitrile was used as mobile phase. Mass spectral data were acquired in both positive and negative modes. On the basis of the characteristic retention time (Rt) and mass spectral data with those of reference standards and relevant references, 73 constituents from the SGJY and 15 ingredients including 10 original constituents and 5 metabolites from the rat plasma after oral administration of SGJY were identified or tentatively characterized. This study provided helpful chemical information for further pharmacology and active mechanism research on SGJY.