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  • Author or Editor: L. Xie x
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Abstract  

Recently P. Mache and M. W. Müller introduced the Baskakov quasi-interpolants and obtained an approximation equivalence theorem. In this paper we consider simultaneous approximation equivalence theorem for Baskakov quasi-interpolants.

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Abstract  

We study the L p -saturation for the linear combination of Bernstein-Kantorovich operators. As a result we obtain the saturation class by using K-functional as well as some modulus of smoothness.

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Abstract  

We investigate the relations between decreasing sequences of sets and the insertion of semi-continuous functions, and give some characterizations of countably metacompact spaces, countably paracompact spaces, monotonically countably paracompact spaces (MCP), monotonically countably metacompact spaces (MCM), perfectly normal spaces and stratifiable spaces.

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The metal-organic framework (MOF) is a kind of new type self-assembly porous coordination polymer, which possesses many characteristics such as homologic hole, controllable size of cave, high specific surface area, and good chemical stability. In this study, a three-dimensional framework [Zn2(d-Cam)2(4,4′-bpy)] n with large homochiral channel and the orderly arrangement of left- and right-handed helices was used as chiral stationary phases (CSPs) in gas chromatography (GC). [Zn2(d-Cam)2 (4,4′-bpy)] n -coated open tubular column was prepared by a dynamic coating method for high-resolution GC. Some racemates, isomers, linear alkanes, and alcohols are used as the targets for separation. The column coating properties efficiency, polarity, and selectivity were studied. The experimental results show that the stationary phase has outstanding selectivity and also possesses good recognition ability toward these compounds.

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Lanzou Alkaline Stretched Noodles (LASN) was a traditional staple food in northwest China for nearly 90 years. LASN specialty wheat breeding has become an important target since 1990s. In order to discover the LASN specialty wheat quality requirement for allelic variations at Glu-3 of northwest China spring wheats. Two northwest China spring wheat cultivars and 39 elite F6 breeding lines were adopted to determine the low-molecular-weight glutenin subunits (LMW-GS) composition by one step one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) basing on the protocol of Singh et al. (1991). The results showed that Glu-A3d and Glu-B3g were correlated to high protein content, high volume of SDS-sediment and super dough strength (W). While Glu-A3a was bad to dry gluten content and SDS-sediment as well as dough properties such as dough strength (W) and dough tenacity (P). Moreover, Glu-B3j has not significant influence on flour quality, but it has the negative effect on dough strength (W) and dough extensibility (L). As for LASN quality, Glu-A3d and Glu-B3g were beneficial alleles and Glu-A3a was unbeneficial alleles for LASN quality.

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Rice straw represents a significant energy source for ruminant animals, and fibers and lignin contents of rice straw are negatively related to intake potential of forages. For improvement of the digestibility of rice straw, it is necessary to understand the genetic basis of the related traits. In present study, mapping of quantitative trait loci (QTL) for acid detergent fiber (ADF), neutral detergent fiber (NDF), and acid detergent lignin (ADL) was carried out using a doubled haploid (DH) population derived from a cross between indica variety Zai-Ye-Qing 8 (ZYQ8) and japonica variety Jing-Xi 17 (JX17). The results indicated that all three parameters were continuously distributed among the DH lines, but many DH lines showed transgressive segregation for all the three traits. A total of three main-effect QTLs were identified for ADF and ADL, two of which, qADF-9 and qADL-9, shared the same region on chromosome 9. These two main-effect QTLs explained more than 20% of the total phenotypic variations, whereas the other QTL, qADF-5, explained 12.8% of the total phenotypic variation for ADF. In addition, another two epistatic QTLs, qADF-2 and qADF-3 could explain 17.6% of the total variations. Thus, we concluded that both main-effects and epistatic QTLs were important in controlling the genetic basis of ADF.

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Abstract  

Aluminum (Al) nanopowders with mean diameter of about 50 nm and passivated by alumina (Al2O3) coatings were prepared by an evaporation route: laser heating evaporation. Thermal properties of the nanopowders were investigated by simultaneous thermogravimetric-differential thermal analysis (TG-DTA) in dry oxygen environment, using a series of heating rates (5, 10, 20, 30, 50 and 90°C min−1) from room temperature to 1200°C. With the heating rates rise, the onset and peak temperatures of the oxidation rise, and the conversion degree of Al to Al2O3 varies. However, the specific heat release keeps relatively invariant and has an average value of 18.1 kJ g−1. So the specific heat release is the intrinsic characteristic of Al nanopowders, which can represent the ability of energy release.

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Abstract  

Thermogravimetric analysis (TG) and Fourier transform infrared (FTIR)results of commercial montmorillonite were compared to that exchanged with trimethyloctadecyl quaternary ammonium chloride (SCPX2048), both were treated up to500C. The time-of-flight mass spectrometer (TOF/MS) results of SCPX2048 trapped under300 and 500C were compared with that of N,N,Ntrimethyl-1-dodecanammonium chloride(A 18-50) trapped under 200 and 300C. The degradation mechanism of organic modified montmorillonite was proposed. PMMA-clay nanocomposite was synthesized through intercalation method and its properties were examined by both TG and DSC techniques. The thermal stability and glass transition temperature of montmorillonite filled PMMA increase comparing with that of the pure PMMA.

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Summary  

Sediment core samples were collected in the largest urban Lake Donghu (Stations I and II) in China, and the activities of 210Pb, 226Ra and 137Cs were measured by gamma-ray spectrometry. The sedimentation rates, calculated by 210Pb constant rate of supply (CRS) model, ranged from 0.11 to 0.65 (average 0.39) cm. y-1at Station I, and from 0.21 to 0.78 (average 0.46) cm. y-1at Station II. Sedimentation rate calculated by 137Cs as a time marker was 0.55 cm. y-1at Station II. Based on the average sedimentation rate, we obtained 769 and 147 t. y-1for nitrogen and phosphorus retentions in Lake Donghu sediments, respectively.

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Abstract

In this study, the ability of microRNA-1906 (miR-1906) to attenuate bone loss in osteoporosis was evaluated by measuring the effects of a miR-1906 mimic and inhibitor on the cellular toxicity and cell viability of MC3T3‐E1 cells. Bone marrow-derived macrophage (BMM) cells were isolated from female mice, and tartrate-resistant acid phosphatase signalling was performed in miR-1906 mimic-treated, receptor-activated nuclear factor kappa-B (NF-κB) ligand (RANKL)-induced osteoclasts. In-vivo, osteoporosis was induced by ovariectomy (OVX). Rats were treated with 500 nmol/kg of the miR-1906 mimic via intrathecal administration for 10 consecutive days following surgery. The effect of the miR-1906 mimic on bone mineral density (BMD) in OVX rats was observed in the whole body, lumbar vertebrae and femur. Levels of biochemical parameters and cytokines in the serum of miR-1906 mimic-treated OVX rats were analysed. The mRNA expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), p-38 and NF-κB in tibias of osteoporotic rats (induced by ovariectomy) was observed using quantitative reverse-transcription polymerase chain reaction. Treatment with the miR-1906 mimic reduced cellular toxicity and enhanced the cell viability of MC3T3‐E1 cells. Furthermore, osteoclastogenesis in miR-1906 mimic-treated, RANKL-induced osteoclast cells was reduced, whereas the BMD in the miR-1906 mimic-treated group was higher than in the OVX group of rats. Treatment with the miR-1906 mimic also increased levels of biochemical parameters and cytokines in the serum of ovariectomised rats. Finally, mRNA expression levels of TLR4, MyD88, p-38 and NF-κB were lower in the tibias of miR-1906 mimic-treated rats than in those of OVX rats. In conclusion, the miR-1906 mimic reduces bone loss in rats with ovariectomy-induced osteoporosis by regulating the TLR4/MyD88/NF‐κB pathway.

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