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  • Author or Editor: Ping Zhang x
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In this paper we introduce differential subordination and superordination properties for certain subclasses of analytic functions involving certain linear operator, and obtain sandwich-type results for the functions belonging to these classes.

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A field experiment was conducted in China during winter season of 2001–2002 to study the response of time of nitrogen application on two cultivars (Xiumei 3 and 92-11) of barley. Apart from basal dose of 40 kg N/ha, 110 kg N/ha was applied at tillering (T 1 ) or in two equal splits at tillering and boot stages (T 2 ) or at boot stage (T 3 ). Cultivar 92-11 attained significantly lower plant height at boot stage and number of spikes/plant but took significantly more number of days to heading, registered significantly more chlorophyll content in leaves at different growth stages, produced significantly more number of grains/spike, grain weight/spike, single grain weight, N concentration at boot stage and consequently produced significantly higher grain yield (3764 kg/ha) than cultivar Xiumei 3 (3201 kg/ha). Application of nitrogen at boot stage significantly reduced the plant height at both stages, dry matter accumulation, days taken to heading, leaf chlorophyll content at boot stage, grains per spike, grain weight per spike and individual grain weight but recorded significantly higher chlorophyll content in leaves at heading stage and higher N content as compared to its application at tillering. Split application of nitrogen at tillering and boot stages also recorded significantly better growth and yield attributes, N concentration and grain yield than its application at boot stage alone but was at par with nitrogen applied at tillering except grain weight per spike. Consequently application of nitrogen at tillering or its split application at tillering and boot stages produced statistically similar (4052 and 3816 kg/ha, respectively) but significantly higher grain yield than its application at boot stage (2500 kg/ha).

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The effect of time of nitrogen application and position of kernels in spike on kernel weight, protein content, β-amylase activity and β-glucan content were examined in two cultivars of barley. Cultivar 92-11 produced significantly bold kernels and lower β-glucan content with slightly lower protein content and higher β-amylase activity than cultivar Xiumei 3. Time of nitrogen application significantly influenced the quality parameters studied. Application of 110 kg N/ha at tillering produced significantly higher kernel weight and significantly lower protein content as well as β-glucan content as compared to its application made at boot stage. β-Amylase activity was also lowest in case of nitrogen applied at tillering stage. There were significant differences between two cultivars for quality parameters when kernels were selected from different spike positions or where specific plant part was removed at heading. The highest 1000-kernel weight was recorded in 92-11 (52.5%) with removal of side tillers and in Xiumei 3 (42.2%) from the middle portion of spike; whereas for protein content, opposite trend was obtained. β-Amylase activity in both cultivars was the highest when middle portion of spike was removed. The lowest β-glucan contents in 92-11 and Xiumei 3 were registered with removal of flag leaf and in Xiumei 3 with the removal of middle portion of spike.

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Journal of Thermal Analysis and Calorimetry
Authors: Xue-Gang Chen, Shuang-Shuang Lv, Ping-Ping Zhang, Lu Zhang and Ying Ye

Abstract

In this study, we ashed rice hull in air and nitrogen, respectively, and systematically investigated the effects of ashing temperature and atmosphere on the structures, morphologies, and pore characteristics of rice hull ash (RHA). All RHA samples are amorphous materials with porous structures. IR spectra revealed that RHA that ashed in air (WRHA) exhibit more polar groups on the surface than that of ashed in nitrogen (BRHA). The silica and carbon contents, BET surface area, and pore volume of BRHA increase with ashing temperature. When ashed in air, however, the silica content of WRHA increases and carbon content decreases with temperature. The BET surface area and pore volume of WRHA increase with temperature firstly and decline subsequently due to the closure of pores. Compared with WRHA, BRHA shows higher surface areas, micropore volumes, carbon contents, and lower mesopore fractions and silica contents. This study provides essential information for choosing a suitable thermal treatment of rice hull for a given adsorbate.

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A simple, rapid, and effective high-performance thin-layer chromatographic (HPTLC) method has been established for differentiating among the polysaccharides present in six traditional Chinese medicines (TCM), Cordyceps sinensis, Ganoderma lucidum, Astragalus memberanaceus, Panax ginseng, Panax quinquefolii , and Panax notogiseng . Acid hydrolyzates of the polysaccharides were analyzed by HPTLC with two detection reagents, aniline-diphenylamine-phosphoric acid and ninhydrin, and scanning densitometry. The compounds were separated on silica gel plates with chloroform- n -butanol-methanol-acetic acid-water 4.5:12.5:5:1.5:1.5 ( v/v ) as mobile phase. Seven monosaccharides and two glucuronic acids were used as reference compounds. The results showed that hydrolysis of polysaccharides can release specific molecules present in the herbal species in addition to the monosaccharides present. This is useful for distinguishing the origins of the polysaccharides in Chinese medicines.

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Abstract  

In this study, the microcalorimetric method was applied to investigate the activity of berberine on Shigella dysenteriae (S. dysenteriae). Heat flow power (HFP)–time curves of the growth metabolism of S. dysenteriae affected by berberine were determined using the thermal activity monitor (TAM) air isothermal microcalorimeter, ampoule mode, at 37 °C. By analyzing these curves and some quantitative parameters using multivariate analytical methods, similarity analysis (SA) and principal component analysis (PCA), the antibacterial activity of berberine on S. dysenteriae could be accurately evaluated from the change of the two main parameters, the maximum heat flow power P m 2 and total heat output Q t: berberine at low concentration (25 μg mL−1) began to inhibit the growth of S. dysenteriae, high concentrations (50–200 μg mL−1) of berberine had strong antibacterial activity on S. dysenteriae, when the concentration of berberine was higher (250–300 μg mL−1), this antibacterial activity was stronger. All these illustrated that the antibacterial activity of berberine on S. dysenteriae was enhanced with the increase of the concentration of this compound. Berberine can be used as potential novel antibacterial agent for treating multidrug-resistant Shigella. This work provided a useful idea of the combination of microcalorimetry and multivariate analysis for studying the activity of other compounds or drugs on organisms.

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Abstract  

Using a LKB-2277 bioactivity monitor, stop-flow mode, the power–time curves of Candida albicans growth at 37 °C affected by berberine were measured. The check experiments were studied based on agar cup method to observe the inhibitory diameter and serial dilution method to determine the minimal inhibitory concentration (MIC) of berberine on C. albicans growth. By analyzing the quantitative thermogenic parameters taken from the power–time curves using correspondence analysis (CA), we could find that berberine at a low concentration (5.0 μg mL−1) began to inhibit the growth of C. albicans and at a high concentration (75.0 μg mL−1) completely inhibited C. albicans growth. The anti-fungal activity of berberine could also be expressed as half-inhibitory concentration IC50, i.e., 50% effective in this inhibition. The value of IC50 of berberine on C. albicans was 34.52 μg mL−1. The inhibitory diameters all exceeded 10 mm in test range and the MIC was 500 μg mL−1. Berberine had strong anti-fungal effect on C. albicans growth. This work provided an important idea of the combination of microcalorimetry and CA for the study on anti-fungal effect of berberine and other compounds. Compared with the agar cup method and serial dilution method, microcalorimetry not only offered a useful way for evaluating the bioactivity of drugs, but also provides more information about the microbial growth and all this information was significant for the synthesis and searching of antibiotics.

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Periodica Mathematica Hungarica
Authors: Peter Buczkowski, Gary Chartrand, Christopher Poisson and Ping Zhang
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Flow chemistry has attracted significant interest in pharmaceutical development, where substantial efforts have been directed toward the design of continuous processes. Here, we report a total synthesis of atropine in flow that features an unusual hydroxymethylation and separation of several byproducts with high structural similarity to atropine. Using a combination of careful pH control in three sequential liquid—liquid extractions and a functionalized resin, atropine is delivered by the flow system with >98% purity.

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Abstract  

Uranyl luminescences in phosphoric acid system has been studied. Uranyl excited by a nitrogen laser shows single or biexponential luminescence decays in the phosphoric acid system. When the uranyl ion or phosphoric acid concentration are lower, a single exponential luminescence decay appears, whereas at higher uranyl ion or phosphoric acid concentrations, biexponential decay is observed. Time-resolved spectra of uranyl in this system are measured. The reasons of the phenomena are tentatively established.

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