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  • Author or Editor: G. Liu x
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Abstract  

Thermal behaviors of two mixed-ligand complexes, [Ni(PMPP-SAL)(Py)3] and [Cu(PMPP-SAL)Py]·MeOH, (PMPP-SAL=1-phenyl-3-methyl-4-(salicylidene hydrazide)-propenylidene-pyrazolone-5, Py=pyridine), were studied by TG-DTG-DTA in dynamic air atmosphere. The complexes show the loss of pyridine molecule is followed by the decomposition of the PMPP-SAL anion and give respective metal oxides as residues. Meanwhile, the Ozawa-Flynn-Wall model-free analyses and multivariate non-linear regressions were applied to perform single and overall steps optimization. Kinetic parameters were given and the most probable mechanism functions were suggested in this study.

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Abstract  

The extraction of U(VI) with newly synthesized alkylamide, N,N-diethyloctadecanamide (DEODA), has been studied. The dependence of the extraction on nitric acid concentration, DEODA concentration and temperature from nitric acid solution has been considered. The extracted species has also been investigated using FT-IR spectrometry. The related themodynamic functions were calculated.

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Abstract  

The determination of the total selenium in different materials is now a routine task for many laboratories. A few problems, however, still remain concerning the choice of an efficient digestion technique and an accurate and precise detection method. For this purpose, we investigated the action of various reagents used for the wet digestion of different materials. Efficient digestion combined with preconcentration were successfully applied to biological samples. Using PIXE, selenium can be detected at 5 ppb level in a short time. The overall performance of wet digestion and PIXE methods were tested with some standard reference materials.

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Abstract  

The enthalpies of dilution, Δdil H m, have been measured for LiCl+Li2B4O7+H2O system at T=298.15 K by using a RD496-III microcalorimeter. A suitable measurement method was used to obtain the better data of the enthalpies of dilution for the ternary mixing solutions to low concentrations. The relative apparent molar enthalpies, L ϕ, have been determined and the relationships between L ϕ and ionic strength I at different molal fractions of Li2B4O7 were obtained. The effect of the borate Li2B4O7 on the heat properties for the studied system was discussed.

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Abstract  

The crystallization dynamics of Nylon 66/Nylon 6 blends, the crystalline/crystalline polymer blends, was analyzed by DSC under isothermal conditions. The crystal growth rate (G) and the nucleation rate (N) depended on both the degree of supercooling (ΔT) and the blend mass fraction (ϕ). The ΔT /T m 0 values obtained at the fixed G, which corresponded to the chemical potential difference of molecules between liquid and crystal states, and the surface free energy parameters evaluated from G and N depended on ϕ for blends. The results suggested that Nylon 66/Nylon 6 blends with ϕN66≥0.80 or ϕN66≤0.15 are miscible.

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Abstract  

Thermal, chemical and rheological properties of ultraviolet aged asphalt binder were characterized by differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) and dynamic shear rheometer (DSR), respectively. Asphalt binder samples were made with different film thickness (50, 100, 200 and 500 μm) and suffered different ageing time (0, 48, 96 and 144 h), at a certain UV radiant intensity of 20 w m–2 in a self-made accelerated ageing oven. The results indicate that the UV light ageing would lead to the improvement of thermal behavior and the growth of the glass transition temperature of asphalt binder. This type of ageing can be also reflected from the FTIR spectra in terms of the characteristic peaks of the carbonyl groups and sulphoxides. The UV light ageing can change some rheological parameters of asphalt binder, such as complex modulus and phase angle. The ageing degrees of asphalt binder by this type of ageing test are mainly related to the ageing time and film thickness of the sample.

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Abstract  

Poly(AN—co—St) (PAS) and poly(AN—St—MMA)(PASM) were synthetized by emulsion polymerisation. The glass transition temperatures (T g) of the copolymers and the relationship between T g and the components of the copolymers were investigated by differential scanning calorimetry. The results show that T g for the AN—St bipolymers has apeak value in the range 115–118°C at a content of 50 mass% St. When methyl methacrylate was added, the T g of the terpolymer was decreased by about 2–6°C.The thermostability and the activation energy E of degradation were determined by thermogravimetric analysis.

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Wheat yellow rust resistance gene Yr17 was originated from the wheat-Aegilops ventricosa introgression, and still effective on the adult plant in Southern China. The previous studies located the gene Yr17 on the translocation of 2NS-2AS using the molecular and cytological markers. In the present study, we screened new PCR-based markers to map the gene Yr17 region from the investigation of a segregating 120 F2 population. All markers including four EST-PCR markers, a SCAR (sequence characterized amplified region) and a PLUG (PCR based landmark unique gene) marker specific to Yr17 gene were mapped on the chromosome 2AS, and located on the chromosomal deletion bin 2AS5-0.8–1.00 region. Based on the wheat-rice collinearity, we found that the sequences of the Yr17 gene linked markers were comparatively matched at rice chromosome 4 and chromosome 7. However, the identified closely linked genomic sequence of Yr17 gene is most likely collinear with genomic region of rice chromosome 4. The newly produced PCR based markers closely linked to Yr17 gene will be useful for the marker-assisted selection in wheat breeding for rust resistance.

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Stripe rust, caused by Puccinia striiformis f. sp. tritici, was one of the most disaster foliar diseases for wheat-growing areas of the world. Thinopyrum intermedium has provided novel resistance genes to multi-fungal disease, and new wheat-Th. intermedium derivatives for stripe rust resistance still need to develop for wheat breeding. Wheat line X484-3 was selected from a cross between wheat line MY11 and wheat-Th. intermedium ssp. trichophorum partial amphiploid TE-1508, and was characterized by genomic in situ hybridization (GISH) and functional molecular markers. Chromosome counting revealed that the X484-3 was 2n = 44 and GISH analysis using Pseudoroegneria spicata genomic DNAas a probe demonstrated that X484-3 contained a pair of St-chromosomes from Th. intermedium donor parents. The functional molecular markers confirmed that introduced St-chromosomes belonging to linkage group 7, indicating that line X484-3 was a 7St addition line. The resistance observation displayed that the introduced Th. intermedium ssp. trichophorum derived chromosomes 7St were responsible for the stripe rust resistances at adult plant. The identified wheat-Th. intermedium chromosome 7St addition line X484-3 can be used as a donor in wheat breeding for stripe rust resistance.

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With the continuous expansion of the global dairy trade market, the quality and safety of the Chinese dairy market have a wide and far-reaching impact on the world. Based on the development of the dairy scandal in the past few years in China, this study illustrates the serious damage of melamine on human health and the negative impact on the dairy industry in China.

This study shows that the lack of effective government regulations is a key reason for dairy market failure. Consumers are lacking confidence in the quality of Chinese dairy products and the government's market regulations. The Chinese dairy market will continue to rely on imported dairy products. By analyzing the typical cases of the dairy market in China, this study aims to provide a guide for dairy industries in other countries.

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