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  • Author or Editor: Y. Zhou x
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Abstract  

The purpose of this paper is to study necessary and sufficient conditions for the Ishikawa iterative sequence with mixed errors of asymptotically quasi-nonexpansive type mappings in Banach spaces to converge to a fixed point in Banach spaces. The results presented in this paper complememt, improve and prefect the corresponding results of [1]–[4] and [7]–[9].

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This study investigated the role of hydrogen sulfide (H2S) in the regulation of ascorbateglutathione (AsA-GSH) cycle by exogenous ABA in wheat leaves under osmotic stress. The results showed that osmotic stress significantly increased the activities of ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR), the ratio of reduced ascorbate to oxidized ascorbate (AsA/DHA) and reduced glutathione to oxidized glutathione (GSH/GSSG), the malondialdehyde content and electrolyte leakage, and the H2S content, compared to control. Exogenous ABA significantly increased above indicators under osmotic stress, compared to osmotic stress alone. Above activity increases except MDHAR activity were suppressed by application of H2S scavenger hypotaurine (HT) and synthesis inhibitor aminooxyacetic acid (AOA). Meanwhile, exogenous ABA significantly decreased malondialdehyde content and electrolyte leakage induced by osmotic stress. Application of HT and AOA reversed above effects of application of exogenous ABA. Application of NaHS can reversed above effects of HT and AOA. Our results suggested that H2S induced by exogenous ABA is a signal that leads to the up-regulation of AsA-GSH cycle.

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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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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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Abstract  

In this paper, the thermogenesis and differential scanning calorimetry (DSC) curves of energy release of the mitochondria isolated from variant strains of cytoplasmic male sterile lines of rices have been determined by using an LKB2277 Bioactivity Monitor and a DuPont 910 differential scanning calorimeter. The regularity and characteristics of the energy release of the mitochondria at constant and changing temperature were investigated, the differences in shape of the curves and the thermodynamic and kinetic characteristics of the thermogenesis of the mitochondria were compared, the thermodynamic and kinetic parameters of energy release of the mitochondria in the thermogenesis increasing stage were calculated, and the experimental thermokinetic equations describing the different thermogenesis processes were established.

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Abstract  

To obtain a biodegradable polymer material with satisfactory thermal properties, higher elongation and modulus of elasticity, a new copolyester, poly(hexylene terephthalate-co-lactide) (PHTL), was synthesized via direct polycondensation from terephthaloyl dichloride, 1,6-hexanediol and oligo(lactic acid). The resulting copolyesters were characterized by proton nuclear magnetic resonance (1H NMR), differential scanning calorimetry (DSC), thermogravimetry (TG) and wide-angle X-ray scattering (WAXS). By using the relative integral areas of the dyad peaks in 1H NMR spectrum of copolyesters PHTL, the sequence lengths of the hexylene terephthalate and lactide units in the resultant copolyesters are 3.5 and 1.5, respectively. Compared to poly(hexylene terephthalate) (PHT), PHTL has lower T m but higher T g due to the incorporation of lactide unit into the main chains of copolyesters. The degradation test of copolyesters under a physiological condition shows that the degradability of PHTL is sped up due to incorporation of lactide segments.

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In the natural populations of common wheat landrace Kaixianluohanmai, there was a phKL gene which promotes homoeologous pairing of wheat-alien hybrids. In the present study, the effects of phKL gene on crossability and homoeologous pairing of Triticum aestivum × Psathyrostachys huashanica Keng ex Kuo hybrids were comparatively analyzed. The crossability of the hybrid between Sichuan wheat landrace Kaixianluohanmai and P. huashanica was highest in all the hybrid combinations with 3.18%. The hybrids T. aestivum (Kaixianluohanmai) × P. huashanica showed a pairing configuration of 21.70 univalents + 2.68 rod bivalents + 0.34 ring bivalents + 0.06 trivalents + 0.02 quadrivalents and 3.54 chiasma per PMC at MI. However, the chiasma in hybrids of CS, CS ph1b , CS ph2a and CS ph2b with P. huashanica was 0.56, 1.90, 0.87 and 0.60, respectively. Compared with the hybrids of CS, CS ph1b , CS ph2a and CS ph2b with P. huashanica , a significant increase in the chiasma of homoeologous pairing was observed in the hybrids of T. aestivum (Kaixianluohanmai) × P. huashanica . The effects were shown in the increment of rod bivalents, ring bivalents and trivalents and reduction of univalents. The results indicated that phKL showed a higher effect on promoting homoeologous pairing than ph1 and ph2 in T. aestivum × P. huashanica . The wheat landrace Kaixianluohanmai with phKL gene is probably a more desirable material for alien gene transferring than Ph2 -deficiency lines.

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Crown rot caused by Fusarium pathogens is one of the most economically destructive diseases of wheat. The objective of this study was to investigate defense-related enzyme responses in wheat seedlings infected with Fusarium graminearum. Three wheat varieties were employed to the experiment. Physiological analysis of varieties indicated that defensive-related enzymes were induced by F. graminearum infection. The superoxide dismutase and peroxidase activities increased dramatically and the phenylalanine ammonia-lyase activity was stimulated to a higher level in resistant variety Hongyouzi than in susceptible variety Wo0102. However, the chitinase activity was higher in susceptible variety Wo0102 than in Hongyouzi after infection. These results suggest that the defense enzymes could be stimulated in wheat seedlings by Fusarium infection.

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