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  • Author or Editor: X. Zhu x
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Abstract  

A procedure for determining Pu in environmental soil using238Pu as a yield tracer is described. The method involves radiochemical separation and electrodeposition onto a stainless steel disc followed by alpha-spectrometric measurement with a solid-state detector. In order to eliminate error in calculation caused by238Pu contained in original samples, a new calculating method is introduced in this paper. By using this method, the activity of238Pu contained in original samples can be substracted from the total activity of samples, to which the238Pu tracer is added. This procedure has been applied satisfactorily to the determination of Pu in a soil reference sample, which was supplied by the Institute of Metrological Science of China.

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Summary

Yanghuo Sanqi tablet (YST), combined prescription mainly derived from the leaves of herba epimedii and the roots of Panax notoginseng, is a traditional Chinese medicine (TCM). Flavonoids (icarrin, epimedin A, epimedin B, epimedin C, and baohuoside I) and saponins (notoginsenoside R1, ginsenoside Rgl, and ginsenoside Rbl) are considered as the main bioactive compounds of YST. However, there is no report on quality control of TCMs by simultaneous determination of above-mentioned flavonoids and saponins so far. In this work, for the first time, a high-performance liquid chromatography-diode array detector-evaporative light-scattering detector (HPLC-DAD-ELSD) method was developed to evaluate the quality of YST through a simultaneous determination of five major active flavonoids and three main saponins. Optimum separations were obtained with a Zorbax SB-C18 column by gradient elution with acetonitrile-water as the mobile phase. The drift tube temperature of ELSD was set at 105 °C, and the nebulizing gas flow rate was 2.5 L min−1. The fully validated method was successfully applied to quantify the eight bioactive components in three lot products. This simple, low-cost, and reliable HPLC-DAD-ELSD method provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

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Summary

Yanghuo Sanqi tablet (YST), combined prescription mainly derived from the leaves of Herba epimedii and the roots of Panax notoginseng, is a traditional Chinese medicine (TCM). Flavonoids (icarrin, epimedin A, epimedin B, epimedin C, and baohuoside I) and saponins (notoginsenoside R1, ginsenoside Rgl, and ginsenoside Rbl) are considered as the main bioactive compounds of YST. However, there is no report on quality control of TCMs by simultaneous determination of above-mentioned flavonoids and saponins so far. In this work, for the first time, a high-performance liquid chromatography-diode array detector-evaporative light scattering detector (HPLC-DAD-ELSD) method was developed to evaluate the quality of YST through a simultaneous determination of five major active flavonoids and three main saponins. Optimum separations were obtained with a Zorbax SB-C18 column by gradient elution with acetonitrile-water as the mobile phase. The drift tube temperature of ELSD was set at 105 °C, and the nebulizing gas flow rate was 2.5 L min−1. The fully validated method was successfully applied to quantify the eight bioactive components in three lot products. This simple, low-cost, and reliable HPLC-DAD-ELSD method provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

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Abstract  

The dilution enthalpies of D-mannitol and D-sorbitol in aqueous sodium chloride solution at various concentrations have been determined by isothermal microcalorimetry at 298.15 K. The homogeneous enthalpic interaction coefficients over a quite large range of concentration of aqueous sodium chloride solutions have been calculated according to the excess enthalpy concept. The results show that enthalpic pairwise interaction coefficients (h 2) of D-mannitol and D-sorbitol are positive in aqueous sodium chloride solution and become more positive with increase of the concentration of sodium chloride. The results are interpreted in terms of the different conformations of the two polyols, solute-solute and solute-solvent interactions involved by solvent effects.

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Abstract  

An Al2(WO4)3 target bombarded with a proton beam (28.5 MeV, 20 A) for 1 hour was completely dissolved in about 5 ml of hot 2N NaOH and the clear solution was neutralized with 2N HCl. The resulted white precipitate of Al2(WO4)3 can be separated from the solution by centrifugation and decantation. The supematant containing radioactive Re as ReO 4 was loaded onto a column (1 cm×10 cm) of activated alumina (100–200 mesh). Eluted with 10 ml of saline, the carrier-free ReO 4 was collected, while the small amount of Al2(WO4)3 in the supematant was adsorbed on the column. The total yield of ReO 4 was 94.7% and the breakthrough of WO 4 2– , only 1.0·10–6 M. The whole separation process can be accomplished within 30 minutes. This rapid and efficient Re/W separation protocol is applicable to the preparation of carrier-free186Re, when an enrichel Al2(186WO4)3 target is used.

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Abstract  

It is proposed to use 14 MeV neutrons tagged by the associated particle neutron time-of-flight technique (APnTOF) to identify the fillers of unexploded ordnances (UXO) by characterizing their carbon, nitrogen and oxygen contents. To facilitate the design and construction of a prototype system, a preliminary simulation model was developed, using the Geant4 toolkit. This work established the toolkit environment for (a) generating tagged neutrons, (b) their transport and interactions within a sample to induce emission and detection of characteristic gamma-rays, and (c) 2D and 3D-image reconstruction of the interrogated object using the neutron and gamma-ray time-of-flight information. Using the modeling, this article demonstrates the novelty of the tagged-neutron approach for extracting useful signals with high signal-to-background discrimination of an object-of-interest from that of its environment. Simulations indicated that an UXO filled with the RDX explosive, hexogen (C3H6O6N6), can be identified to a depth of 20 cm when buried in soil.

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A rapid, simple, and practical high-performance liquid chromatographic method (HPLC) was developed and validated for the simultaneous determination of norephedrine (NME), norpseudoephedrine (NMP), ephedrine (E), pseudoephedrine (PE), and methylephedrine (ME) in traditional Chinese medicines (TCM) which contained Ephedrae Herba (Ephedra). This analysis could be accomplished within 12.5 min with an Alltima Phenyl Column by isocratic elution using a mixture of KH2PO4 (20 mM)-acetonitrile (96:4, v/v) as the mobile phase at a flow-rate of 0.6 mL min−1 and a wavelength of 210 nm. This method was successfully applied to quantify ephedra alkaloids in both Ma-xing-gan-shi decoction and Ephedra decoction. The concentration of total ephedra alkaloids (4.62 mg mL−1) in Ma-xing-gan-shi decoction was much lower than that (7.10 mg mL−1) in Ephedra decoction. Furthermore, the concentration of NME, NMP, E, PE, and ME was significantly lower in Ma-xing-gan-shi decoction than that in Ephedra decoction, respectively. The method was easily acceptable and would be popular with most analytical laboratories.

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Abstract  

Polyacrylamide (PAM), poly(N,N-dimethylacrylamide) (PDMA) and poly(N,N-diethylacryl-amide) (PDEA) were synthesized by plasma-initiated polymerization. Both wet and dry polymers were prepared. The states of the water absorbed in the wet and dry samples were studied directly by means of TG, and the stabilities of the dry polymers in the process of thermal treatment were investigated by FT-IR. The activation energy of release of the bonded water was calculated by the Kissinger method. The water absorbed in the polymers was found to be in two states, i.e. weakly-bonded water and bonded water, and the absorbed water content varied with the monomer concentration, the plasma duration time and the type of polymer.

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Seed germination is a new beginning for the crop life cycle, which is closely related to seed sprouting and subsequent plant growth and development, and ultimately affects grain yield and quality. Salt stress is one of the most important abiotic stress factors that restrict crop production. Therefore, it is highly important to improve crop salt tolerance and sufficient utilization of saline-alkali land. In this study, we identified the phosphorylated proteins involved in salt stress response by combining SEM, 2-DE, Pro-Q Diamond staining and tandem mass spectrometry. The results showed that salt stress significantly inhibited seed germination and starch degradation. In total, 14 phosphorylated protein spots (11 unique proteins) in the embryo and 6 phosphorylated protein spots (4 unique proteins) in the endosperm were identified, which mainly involved in stress/defense, protein metabolism and energy metabolism. The phosphorylation of some proteins such as cold regulated proteins, 27K protein, EF-1β and superoxide dismutase could play important roles in salt stress tolerance.

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Summary

An efficient and robust method for analyzing constituents of a well-known traditional Chinese medicine (TCM) formula SiWu decoction (SWD) contains Angelicae Sinensis Radix (ASR), Chuanxiong Rhizoma (CR), Paeoniae Radix Alba (PRA), and Rehmanniae Radix Praeparata (RRP) by ultra high-performance liquid chromatography (UHPLC)/time-of-flight mass spectrometry (TOF-MS) was established. The method efficiently applied to the separation of 75 compounds, including organic acids, phthalides, phenylpropanoid glycosides, iridoid glycosides, monoterpene glycosides, and galloyl glycosides in the complex prescription, 52 compounds in this study can be unambiguously identified or tentatively characterized. The separation was achieved within 20 min at the optimized chromatographic conditions. Our study provided a reliable and high-efficient method for the understanding of the chemical basis of SWD.

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