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  • Author or Editor: L. Peng x
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Abstract  

Several interpolation theorems on martingale Hardy spaces over weighted measure spaces are given. Our proofs are based on the atomic decomposition of martingale Hardy spaces over weighted measure spaces. As applications of interpolation theorems, some inequalities of martingale transform operator are obtained.

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Abstract  

The biological activity of a kind of hetero-bimetallic Schiff-base complex was studied using Escherichia coli (E. coli) cell as the target. By microcalorimetry, the difference of anti-bacterial activity between the binuclear Schiff-base and the ligand was determined and analyzed. To analyze the inhibition of the bacterial growth internally, the E. coli cells grown in the presence of hetero-bimetallic Schiff-base complex were observed by scanning electron microscopy. The images in high resolution revealed the damage of outer cell membrane caused the inhibitory effect on E. coli. Inductively coupled plasma-mass spectrometry results proved the absorption of the complex by cells, which confirmed the interaction between the Schiff-base and biological macromolecule.

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Abstract  

Three samples of silicon dioxide were syhthesized and their surface areas were measured. A thermo-chemical cycle was designed to calculate the molar formation enthalpy. The molar formation enthalpy, Δf H m Φ, for three amorphous silica with the Langmuir surface area 198.0854, 25.1108 and 11.9821 m2 g−1 gave −895.52, −910.86 and −915.67 kJ mol−1, respectively. With the increasing surface area, the values of Δf H m Φ increased accordingly. The results suggest that the silica with larger surface area is more unstable. The wetting heat was also measured by adding the silica powder into water. With the rehydration of the more SiOH groups on the surface, the larger surface areas of silica lead to the more wetting heat. A smaller particle has the more unstable hydroxyl groups and surface energy.

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Abstract  

The standard molar enthalpy of combustion of cholesterol was measured at constant volume. According to value of Δr U m θ(−14358.4±20.65 kJ mol−1), Δr H m θ(−14385.7 kJ mol−1) of combustion reaction and Δf H m θ(2812.9 kJ mol−1) of cholesterol were obtained from the reaction equation. The enthalpy of combustion reaction of cholesterol was also estimated by the average bond enthalpies. By design of a thermo-chemical recycle, the enthalpy of combustion of cholesterol were calculated between 283.15∼373.15 K. Besides, molar enthalpy and entropy of fusion of cholesterol was obtained by DSC technique.

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Abstract  

Retention indexes (RI's) on SE-30 and Carbowax 20M columns are characteristic and can be used for identification purposes. A method for predicting RI on the basis of the number of atoms and contributions from substituents and functional groups is discussed. This method establishes a structure retention index relationship (SRIR), capable of relating structure to RI and is useful for suggesting structure to match with radioactive peaks. Examples of labeled side products tentatively identified in this manner are given.

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Summary

In the present paper, a simple and reliable high-performance liquid chromatography-diode array detection (HPLC-DAD) method was developed both for quantitative determination and fingerprint analysis of Agrimonia pilosa Ledeb for quality control. Under the optimized HPLC conditions, seven bioactive compounds including rutin, quercetin-3-rhamnoside, luteoloside, tiliroside, apigenin, kaempferol, and agrimonolide were determined simultaneously. For fingerprint analysis, 11 common peaks were selected as the characteristic peaks to evaluate the similarities of 16 different samples collected from different origins in China. Besides, hierarchical cluster analysis (HCA) was also performed to evaluate the variation of the raw materials. This is the first report of using a simple method for quality control of A. pilosa Ledeb through multi-component determination and chromatographic fingerprint analysis to the best of our knowledge.

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The purpose of this study was to investigate the effects of endophytic fungi from tartary buckwheat on the host sprout growth and functional metabolite production. Without obvious changes in the appearance of the sprouts, the exogenous fungal mycelia elicitors notably stimulated the sprout growth and rutin accumulation, and the stimulation effect was mainly depended on the mycelia elicitor species along with its treatment dose. Three endophytic fungi Fat6 (Bionectria pityrodes), Fat9 (Fusarium oxysporum) and Fat15 (Alternaria sp.) were screened to be the most effective candidates for promoting F. tataricum sprout growth and rutin production. With application of polysaccharide (PS, 150 mg/l) of endophyte Fat6, PS (200 mg/l) of endophyte Fat9, and PS (150 mg/l) of endophyte Fat15, the rutin yield was effectively increased to 47.89 mg/(100 sprouts), 45.85 mg/(100 sprouts) and 46.83 mg/(100 sprouts), respectively. That was about 1.5- to 1.6-fold compared to the control culture of 29.37 mg/(100 sprouts). Furthermore, the present study revealed that the biosynthesis of the functional flavonoid resulted from the stimulation of the phenylpropanoid pathway by mycelia polysaccharide treatments. Application of specific fungal elicitors could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts.

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Abstract  

A microcalorimetric technique was used to evaluate the influence of La3+ on mitochondria isolated from the liver tissue of Avian chicken. By means of LKB-2277 bioactivity monitor, ampoule method at 37C, we obtained the thermogenic curves of the metabolism of mitochondria. After isolation from the chicken liver tissue, mitochondria still have metabolic activity and can live for a long time depending on the stored nutrients. In order to analyze the results, the maximum power (P m) and the decline rate constants (k d) were obtained. The addition of La3+ results in an increase of the maximum heat production and decline rate constants. Furthermore, values of P m and k d are linked to the concentration of La3+. According to the thermogenic curves under different conditions, it is clear that metabolic mechanism of mitochondria has been changed with the addition of La3+.

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This study was to examine the effects of four fungal polysaccharides, namely exo-polysaccharide (EPS), water-extracted mycelia polysaccharide (WPS), sodium hydroxideextracted mycelia polysaccharide (SPS), and hydrochloric-extracted mycelia polysaccharide (APS) obtained from the endophytic fungus Bionectra pityrodes Fat6, on the sprout growth and flavonoids production of Fagopyrum tataricum. Without obvious changes in the appearance of the sprouts, the exogenous polysaccharide elicitors notably stimulated the sprout growth and functional metabolites accumulation, and the stimulation effect was mainly depended on the polysaccharide species along with its treatment dose. With application of 150 mg/l of EPS, 150 mg/l of WPS and 200 mg/l of SPS, the total rutin and quercetin yield of buckwheat sprouts was effectively increased to 49.18 mg/(100 sprouts), 50.54 mg/(100 sprouts), and 52.27 mg/(100 sprouts), respectively. That was about 1.57- to 1.66-fold in comparison with the control culture of 31.40 mg/(100 sprouts). Moreover, the present study revealed the accumulation of bioactive flavonoids resulted from the stimulation of the phenylpropanoid pathway by fungal polysaccharide treatments. It could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts applied with specific fungal elicitors.

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