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  • Author or Editor: Tao Wang x
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A simple and accurate high-performance thin-layer chromatography (HPTLC)-bioautographic method was developed for the quantitative analysis of magnolol and honokiol in the herbal medicine Magnoliae officinalis Cortex. The samples were separated on a silica gel HPTLC plate with a mixture solution of toluene-methanol (10:1, v/v) as the mobile phase. Spots were visualized by dipping in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*) reagent and measured at a wavelength of 550 nm in a reflection mode, scanning after derivatization for 40 min. The method had excellent linearity (r 2 = 0.9939 for magnolol and r 2 = 0.9989 for honokiol, respectively) in the concentration range of 0.16–0.97 mg spot−1 for both analytes. The recoveries were 94.5–105.9% for magnolol and 86.6–103.4% for honokiol, respectively. The established HPTLC-bioautographic method was evaluated comprehensively in quantitative and antioxidant activity analysis of magnolol and honokiol in Magnoliae officinalis Cortex and various plants.

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The effect of different solid components of calcareous soil on the retention of Sr was investigated by using batch technique and selective extraction method. The sorption and desorption isotherms of Sr on the untreated calcareous soil and the three treated soils were determined at 20°C, pH 7.8±0.2 and in the presence of 0.001 M CaCl2. It was found that all isotherms are linear and that the sorption of Sr on the calcareous soil can be described by a reversible sorption process and the sorption mechanism is mainly ion exchange.

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To investigate the prevalence and characteristics of the practice of explicitly giving authors equal credit in publications of major anesthesiology journals. Four major anesthesiology journals (Anesthesia and Analgesia (AA), Anesthesiology, British Journal of Anaesthesia (BJA) and Pain) were searched manually to identify original research articles published between January 1st, 2001 and December 31st, 2010 with respect to equally credited authors (ECAs). It was found that all journals explicitly gave authors equal credit, and articles with ECAs accounted for a greater proportion of the total number of articles published in each journal in 2010 versus that in 2000 (AA: 3.3% vs. 0%; Anesthesiology: 7.1% vs. <1%; BJA: 5.7% vs. 0%; Pain: 11.0% vs. <1%). The number of ECAs articles tended to increase significantly yearly in all journals (P < 0.0001 for each journal). The first two authors in the byline received equal credit in most cases. Furthermore, the ECAs articles involved institutions from different countries and regions and were sponsored by various funds. However, no specific guidance concerning this practice was provided in the instructions to authors in the four journals. It is increasingly common to give authors equal credit in original research articles in major anesthesiology journals. Detailed guidelines regarding this practice are warranted in future.

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36 kinds of mixed carbonate molten salts were prepared by mixing potassium carbonate, lithium carbonate, sodium carbonate in accordance with different proportions. The data of melting point and latent heat are measured by the analysis of DSC curves of 36 kinds of salts, which show that the majority of ternary carbonate’s melting points are close at around 400 °C. 24 kinds of eutectic molten salts were selected among 36 kinds of molten salts. With high latent heat, ternary carbonate salt has the potential to be employed for phase change thermal storage. The costs for phase change thermal storage of 24 kinds of carbonate salts are calculated. Finally, 13 kinds of ternary carbonate salts with lower cost for phase change thermal storage are recommended, where there are 6 kinds of mixed carbonates have the considerably larger latent heat of melting.

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The effect of various solid soil components on the retention of Cs was investigated by using batch technique and selective extraction method. The sorption and desorption isotherms of Cs on the untreated, calcareous soil and the three treated soils were determined at 20°C, pH 7.8±0.2 and in the presence of 0.001M CaCl2. It was found that all isotherms are nonlinear, and that the sorption-desorption hysteresis on the calcareous soil actually occurs on the same time scale.

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The distribution coefficients of 47 elements from Na to Bi on untreated calcareous soil, treated soil to remove CaCO3 and treated soil to remove both CaCO3 and organic matter, respectively, were determined by using a multitracer technique. The variation of the distribution coefficients of 47 elements was explained in terms of chemical bond formation and hydration. The effect of different solid components of the calcareous soil on the adsorption was investigated.

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Co–Mo–O–B amorphous catalysts were prepared by the chemical reduction method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), inductively coupled plasma (ICP) and X-ray photoelectron spectroscopy (XPS). The hydrodeoxygenation (HDO) properties of these catalysts were tested using phenol as the model compound. The catalyst preparation time had no influence on their amorphous structure but a great effect on the catalyst surface composition and the HDO activity. With the prolongation of preparation time, the catalyst particle size and the relative content of Co on the catalyst surface were increased gradually. The conversion of phenol could be as high as 100% with a selectivity of 99.6% for deoxygenation. The aromatics content in the products could be decreased to below 2% and the total H/C atomic ratio could be improved to 1.98. The pseudo first-order reaction rate constant of the phenol transformation on Co–Mo–O–B amorphous catalyst was high to 0.67 mL/(g catalyst s). The main reaction route in the HDO of phenol on Co–Mo–O–B amorphous catalyst proceeded with hydrogenation–dehydration rather than direct hydrogenolysis.

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Th(NO3)4 was irradiated with 25 MeV/nucleon 40Ar ion beam. The target material irradiated was dissolved in 12 mol/l HCl and the Th in the HCl solution was extracted with 20% (V/V) TBP solution in CCl4 successively, then the TBP solution remaining in the aqueous phase after 4 successive extractions was stripped with benzene. A carrier-free and salt-free multitracer solution containing 38 elements from Be to Bi and 67 radionuclides was prepared. The convenient extraction method was developed for the separation between the target material Th(NO3)4 and the large number of fission products.

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Although significant progress has been made on Agrobacterium -mediated wheat transformation, the current methodologies use immature embryos as recipient tissues, a process which is labor intensive, time consuming and expensive. In this study, we have managed to develop an Agrobacterium -based transformation scheme using explants derived from mature embryos. Based on transient expression of β -glucuronidase (GUS) marker, mature embryo halves prepared from freshly imbibed seeds were generally most susceptible to Agrobacterium -mediated T-DNA transfer. According to the results of callus induction and shoot production, Yumai 66 and Lunxuan 208 showed higher selection and regeneration efficiency than Bobwhite. In line with this finding, fertile T 0 transgenic plants were most readily obtained for both spring and winter wheat when mature embryo halves were used for co-inoculation by Agrobacterium cells. The presence of the antibiotic selection marker ( nptII , encoding neomycin phosphotransferase II) in the T 0 plants was revealed by both genomic PCR amplification and the enzyme-linked immunosorbent assay (ELISA). Additional analysis showed that the transgene was stably inherited from the two different generations and segregated normally among the T 1 progenies. Further development along this line will raise the efficiency of wheat transformation and increase the use of this approach in the molecular breeding of wheat crop.

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