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  • Author or Editor: Y. Jiang x
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Abstract

The phenomenon of all-elements-sleeping-beauties in science is revealed by four special cases. The ‘sleeping beauties’ prick their fingers on the ‘spindles’ so that they fall into sleep then are awakened by their ‘princes’. The authors speculate that the phenomenon could happen in scientific literatures with high quality.

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Abstract  

The production rates (numbers of atoms per gram of the respective elements per second) of 40 radioactive nuclides of 34 elements by neutron capture reactions in a reactor were determined from about 130 photopeaks of the -ray spectra. The ratios of these production rates were called R-matrix elements. These production rates and the respective thermal neutron capture cross sections were used to calculate the respective apparent neutron fluxes at the position of irradiation and the -matrix elements which were the ratios of these apparent neutron fluxes. These matrix elements express clearly the correlations among various elements and thus may be used in the mono-standard or small-number-standards method in neutron activation analysis.

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Abstract  

A series of UO2 2+ complex with monoamide ligand was isolated. The complexes have been characterized with the aid of 13C and 1HNMR spectroscopic studies. The result shows that the amide ligand directly coordinates to the uranyl(VI) ion through its carbonyl group. The change of the value of the chemical shift due to the complexation has been discussed.

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Abstract  

Ammonium niobium oxalate was prepared and characterized by elemental analysis, XRD and FTIR spectroscopy analysis, which confirmed that the molecular formula of the complex is NH4(NbO(C2O4)2(H2O)2)(H2O)3. Dynamic TG analysis under air was used to investigate the thermal decomposition process of synthetic ammonium niobium oxalate. It shows that the thermal decomposition occurs in three stages and the corresponding apparent activation energies were calculated with the Ozawa–Flynn–Wall and the Friedman methods. The most probable kinetic models of the first two steps decomposition of the complex have been estimated by Coats–Redfern integral and the Achar–Bridly–Sharp differential methods.

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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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Abstract  

New special engineering thermoplastics, poly(phthalazinone ether sulfone) (PPES) and poly(phthalazinone ether sulfone ketone) (PPESK), containing phthalazinone are synthesized through step-polymerization. The kinetics of thermal degradation of PPES and PPESK (1/1) in nitrogen is investigated at several heating rates by thermogravimetry (TG). It is concluded that, based on using Satava’s theory, the thermal degradation mechanism of PPESK (1/1) is nucleation and growth, the order of reaction of the degradation process is one (n = 1). In contrast, the thermal degradation mechanism of PPES is a phase boundary controlled reaction and the order of the reaction is two (n = 2). The kinetic parameters, including reaction energy and frequency factor of thermal degradation reaction for PPES and PPESK (1/1) are analyzed using isoconversional Friedman, Kissinger–Akahira–Sunose (K–A–S) and Ozawa method. In addition, the study focus on the influence of heating rate and ratio of ketone/sulfone on thermal stability and the life estimation are described.

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Abstract

High-performance liquid chromatography with a hydrophilic-interaction liquid chromatographic (HILIC) column has been successfully used to retain and separate the polar phosphonic herbicides glyphosate and glufosinate. Online electrospray tandem ion-trap mass spectrometric and DAD detection were used. The effects on the separation of mobile phase acetonitrile content, buffer concentration, and flow rate, and of column temperature, were investigated. With UV-visible detection at 195 nm, LOQ were <850 mg kg−1, showing the method is suitable for product quality control of these herbicides alone or in combination. Tandem mass spectrometric conditions were optimized for ion-trap detection. Quantification was by use of selected reaction monitoring transitions m/z 168 → 150 in negative-ion mode for glyphosate and m/z 182 → 136 in positive-ion mode for glufosinate. Limits of detection (LOD; S/N > 3) were 0.20 and 0.16 ng for glyphosate and glufosinate, respectively, and the respective limits of quantification (LOQ; S/N = 10) were 0.02 and 0.05 mg kg−1. Sample derivatization was not necessary to achieve low detection limits in residue analysis in this study. Recovery from watermelon, spinach, potato, tomato, radish-root, and water fortified with the herbicides ranged from 63.6 to 107.3% and relative standard deviations were <15.3%.

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Aegilops sharonensis (Sharon goatgrass) is a valuable source of novel high molecular weight glutenin subunits, resistance to wheat rust, powdery mildew, and insect pests. In this study, we successfully hybridized Ae. sharonensis as the pollen parent to common wheat and obtained backcross derivatives. F1 intergeneric hybrids were verified using morphological observation and cytological and molecular analyses. The phenotypes of the hybrid plants were intermediate between Ae. sharonensis and common wheat. Observations of mitosis in root tip cells and meiosis in pollen mother cells revealed that the F1 hybrids possessed 28 chromosomes. Chromosome pairing at metaphase I of the pollen mother cells in the F1 hybrid plants was low, and the meiotic configuration was 25.94 I + 1.03 II (rod). Two pairs of primers were screened out from 150 simple sequence repeat markers, and primer WMC634 was used to identified the presence of the genome of Ae. sharonensis. Sequencing results showed that the F1 hybrids contained the Ssh genome of Ae. sharonensis. The sodium dodecyl sulfate polyacrylamide gel electrophoresis profile showed that the alien high molecular weight glutenin subunits of Ae. sharonensis were transferred into the F1 and backcross derivatives. The new wheat-Ae. sharonensis derivatives that we have produced will be valuable for increasing resistance to various diseases of wheat and for improving the quality of bread wheat.

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To study the development of starch granules in polyploid wheats, we investigated the expression of starch synthetic genes between the synthetic hexaploid wheat SHW-L1, its parents T. turgidum AS2255 and diploid Ae. tauschii AS60. The synthetic hexaploid wheat SHW-L1 showed significantly higher starch content and grain weight than its parents. Scanning electron microscopy (SEM) showed that SHW-L1 rapidly developed starch granules than AS2255 and AS60. The amount of B-type granule in AS60 was less than that in SHW-L1 and AS2255. RT-qPCR result showed that the starch synthetic genes AGPLSU1, AGPLSU2, AGPSSU1, AGPSSU2, GBSSI, SSIII, PHO1 and PHO2 expressed at earlier stages with larger quantity in SHW-L1 than in its parents during wheat grain development. The expression of the above mentioned genes in AS60 was slower than in SHW-L1 and AS2255. The expression pattern of starch synthase genes was also associated with the grain weight and starch content in all three genotypes. The results suggested that the synthetic hexaploid wheat inherited the pattern of starch granule development and starch synthase gene expression from tetraploid parent. The results suggest that tetraploid wheat could plays more important role for starch quality improvement in hexaploid wheat.

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