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Structural heredity of TiC and its influences on refinement behaviors of AlTiC master alloy

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中国有色金属学会会刊：英文版 2003年第4期13卷 790-793页

作者：王振卿刘相法柳延辉张均燕于丽娜边秀房 key laboratory of Liquid Structure and heredity of Materials

heredity of microstructure in AlTiC master alloy, grain refiners, was analyzed. It is found that, for morphologies and distributions of TiC particles, there are visible heredity which originates from raw materials or processing methods of Al melt, and will ultimately be transferred to the solid state structure through the melt stage, and this phenomenon can cause hereditary influences on refinement: formation of chain like TiC morphology results in rapid refinement fading behavior; distribution of TiC along grain boundaries greatly reduces refinement efficiency. Controlling of structural heredity through proper selections of raw materials and processing parameters is of great importance in obtaining ideal microstructures and improving refinement behaviors of AlTiC master alloys.

关键词： AlTiC合金碳化钛结构遗传铝合金精炼

Mechanical properties and microstructure of Fe-Al/Al_2O_3 composite with Cr,Mo and Ti

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中国有色金属学会会刊：英文版 2003年第4期13卷 860-863页

作者：李爱民孙康宁毕见强尹衍升张玉军 key laboratory for Liquid Structure and heredity of Materials

When Cr, Mo and Ti were added to Fe Al/Al 2O 3 composite, the bending strength and fracture toughness of the composite were increased sharply. The highest value of bending strength can exceed 600 MPa and the average value of fracture toughness exceed 12 MPa·m 1/2 . With increasing content of Mo and Ti, the bending strength and fracture toughness both express the trend of increasing first and then decreasing. When the alloying elements were added to the composites the alloying extent is improved. The fracture mode of the composites are mainly transcrystalline.

关键词： Fe-Al合金费尔合金机械性能显微结构 Fe-Al/Al2O3复合材料铬锰钛

Effect of Sn on as-cast ageing behavior of Al-Si-Mg alloy

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中国有色金属学会会刊：英文版 2003年第3期13卷 626-631页

作者：王桂青边秀房段佑峰张均艳 The key laboratory of Liquid Structure and heredity of Materials

The effect of minor additions of Sn on the as cast ageing behavior of Al 11Si 0.35Mg alloy was investigated. It is shown that precipitation has been retarded in Sn containing alloy and more time is needed to reach its peak hardness,which is bigger than that of the base alloy. Analysis of the kinetic data shows that Sn addition does not change the growth dependent parameter n , but increases the nucleation density dependent parameter k . TEM results show that there are little precipitates in Sn containing alloy at the initial stage of as cast ageing. However, the Sn addition increases the net density of precipitates during as cast ageing, because there are many dislocation loops formed as ageing progresses and Sn segregated at the edges of dislocation loops, which acts as the nuclei of precipitates.

关键词：成核密度铝合金锡时效铸造铝合金析出 TEM

Correlation between local clusters and structure of Al_(71) Cu_(29) melt

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中国有色金属学会会刊：英文版 2003年第2期13卷 344-347页

作者：陈莹边秀房孙民华王丽 key laboratory of Liquid Structure and heredity of Materials

The structures of Al 14 Cu 12 clusters were optimized by B3LYP method and the six geometries ground states were obtained. Al 71 Cu 29 alloy melt has been investigated using X ray diffractometry at 700 ℃. The experimental data were compared with calculated results to find the relation between the structures of Al Cu clusters and melt structure. It is shown that there exists a strong interaction between Al and Cu atoms. The bond length in some geometries is very close to the experimental atomic distance. Such optimized geometries have close correlation with the liquid structure of Al Cu alloy.

关键词：铝合金熔炼结构 X射线衍射组织

Differentiation of expression profi les of two calcineurin subunit genes in chicken skeletal muscles during early postnatal growth depending on anatomical location of muscles and breed

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Journal of Integrative Agriculture 2016年第5期15卷 1085-1094页

作者： SHAN Yan-ju XU Wen-juan SHU Jing-ting ZHANG Ming SONG Wei-tao TAO Zhi-yun ZHU Chun-hong LI Hui-fang key laboratory for poultry Genetics and breeding of Jiangsu Province Institute of Poultry Science Chinese Academy of Agricultural Science

Calcineurin（Cn or CaN） is implicated in the control of skeletal muscle fiber phenotype and hypertrophy. However, little information is available concerning the expression of Cn in chickens. In the present study, the expression of two Cn subunit genes（Cn Aα and Cn B1） was quantified by q PCR in the lateral gastrocnemius（LG, mainly composing of red fast-twitch myofibers）, the soleus（mainly composing of red slow-twitch myofibers） and the extensor digitorum longus（EDL, mainly composing of white fast-twitch myofibers） from Qingyuan partridge chickens（QY, slow-growing chicken breed） and Recessive White chickens（RW, fast-growing chicken breed） on different days（1, 8, 22, 36, 50 and 64 days post-hatching）. Although Cn Aα and Cn B1 gene expressions were variable with different trends in different skeletal muscles in the two chicken breeds during postnatal growth, it is highly muscle phenotype and breed specific. In general, the levels of Cn Aα and Cn B1 gene expressions of the soleus were lower than those of EDL and LG in both chicken breeds at the same stages. Compared between the two chicken breeds, the levels of Cn Aα gene expression of the three skeletal muscles in QY chickens were higher than those in RW chickens on days 1 and 22. However, on day 64, the levels of both Cn Aα and Cn B1 gene expressions of the three skeletal muscles were lower in QY chickens than those in RW chickens. Correlation analysis of the levels of Cn Aα and Cn B1 gene expressions of the same skeletal muscle showed that there were positive correlations for all three skeletal muscle tissues in two chicken breeds. These results provide some valuable clues to understand the role of Cn in the development of chicken skeletal muscles, with a function that may be related to meat quality.

关键词： calcineurin chicken skeletal muscle expression

Electromagnetic Characteristic of Twin-wire Indirect Arc Welding

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 123-131页

作者： SHI Chuanwei ZOU Yong ZOU Zengda WU Dongting key laboratory of Liquid Structure and heredity of Materials Shandong University

Traditional welding methods are limited in low heat input to workpiece and high welding wire melting rate. Twin-wire indirect arc（TWIA） welding is a new welding method characterized by high melting rate and low heat input. This method uses two wires one connected to the negative electrode and another to the positive electrode of a direct-current（DC） power source. The workpiece is an independent, non-connected unit. A three dimensional finite element model of TWIA is devised. Electric and magnetic fields are calculated and their influence upon TWIA behavior and the welding process is discussed. The results show that with a 100 A welding current, the maximum temperature reached is 17 758 K, arc voltage is 14.646 V while maximum current density was 61 A/mm2 with a maximum Lorene force of 84.5 ~tN. The above mentioned arc parameters near the cathode and anode regions are far higher than those in the arc column region. The Lorene force is the key reason for plasma velocity direction deviated and charged particles flowed in the channel formed by the cathode, anode and upper part of arc column regions. This led to most of the energy being supplied to the polar and upper part of arc column regions. The interaction between electric and magnetic fields is a major determinant in shaping TWIA as well as heat input on the workpiece. This is a first study of electromagnetic characteristics and their influences in the TWIA welding process, and it is significant in both a theoretical and practical sense.

关键词： twin-wire indirect arc welding electromagnetic simulation

Preparation and mechanical properties of Fe_3Al/Al_2O_3 nano-/micro-composite

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中国有色金属学会会刊：英文版 2003年第6期13卷 1376-1380页

作者：尹衍升龚红宇范润华王昕谭训彦 key laboratory for Material Liquid Structure and heredity of Education Ministry

Al2O3 matrix composites reinforced with Fe3Al nano-particles were fabricated by hot processing at 1 4501 600 ℃. The effect of Fe3Al content on the densification, mechanical properties and microstructure of the composites was investigated. The results show that some elongated Al2O3 grains are observed. Fe3Al particles are mainly situated at grain boundaries of the matrix while smaller particles are trapped within the alumina grains. The addition of Fe3Al nanoparticles improves the mechanical properties of alumina. The maximum strength and toughness of the Fe3Al/Al2O3 nanocomposites are 832 MPa and 7.96 MPa·m1/2, respectively.

关键词： Fe3Al/Al2O3 纳米复合材料铝合金制备机械性能

Effect of yttrium on thermal stability and crystallization behavior of Nd_(60)Fe_(20)Al_(10)Ni_(10) amorphous alloys

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Journal of Rare Earths 2008年第5期26卷 735-740页

作者：张莎莎田学雷孔凡利 key laboratory of Liquid Structure and heredity of Materials Ministry of Education Shandong University

The effect of yttrium on the thermal stability and crystallization behavior of Nd-Fe-Al-Ni amorphous alloys was investigated using X-ray diffraction （XRD）, differential scanning calorimeter （DSC）, and transmission electron microscopy （TEM）.The results indicated that the as-cast Nd60Fe20Al10Ni10-xYx（X=-0, 2） amorphous alloys were fabricated with some quenched-in crystals, which could be restrained by Y. With the effect of yttrium, both the crystallization temperature and exothermic peak shifted to higher temperatures, illustrating that the thermal stability could be improved. The addition of Y changed the crystallization process and final crystallization results. Moreover, the crystallites in the amorphous matrix became more homogeneous and smaller. Meanwhile, Y was useful for the passivation of oxygen in chemistry and restrained the negative effect of oxygen. The activation energies of the start of crystallization and peaking were 1.21 and 1.16 eV, respectively, according to the Kissinger equation.

关键词： Nd-based amorphous alloy quenched-in crystals thermal stability crystallization behavior activation energy rare earths

In ovo leptin administration affects hepatic lipid metabolism and microRNA expression in newly hatched broiler chickens

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Journal of Animal Science and Biotechnology 2012年第2期3卷 77-85页

作者： Yan Hu Rui Zhang Yanhong Zhang Jing Li Roland Grossmann Ruqian Zhao key laboratory of Animal Physiology&Biochemistry Nanjing Agricultural University Nanjing210095China key laboratory of poultry heredity&breeding Institute of Poultry Science of Jiangsu ProvinceYangzhou225003China Department of Functional Genomics&Bioregulation Institute of Animal Science Mariensee31535NeustadtGermany

Background： A leptin-like immunoreactive substance has been found in chicken eggs and has been implicated in serving as a maternal signal to program offspring growth and metabolism. In the present study, we investigated the effects of in ovo leptin administration on hatch weight, serum and hepatic concentrations of metabolites and hormones, as well as on the expression of genes involved in hepatic lipid metabolism and the predicted microRNAs （miRNAs） targeting the affected genes. To this end we injected fertile eggs with either 0.5 μg of recombinant murine leptin or vehicle （PBS） before ***： Prenatally leptin-exposed chicks showed lower hatch weight, but higher liver weight relative to the body weight, compared to the control group. In ovo leptin treatment increased the hepatic content and serum concentration of leptin in newly hatched chickens. The hepatic contents of triglycerides （TG） and total cholesterol （Tch） were decreased, whereas the serum levels of TG, Tch and apolipoprotein B （ApoB） were increased. The hepatic mRNA expression of sterol regulator element binding protein 1 （SREBP-1c）, SREBP-2, hydroxy-3-methylglutaryl coenzyme A reductase （HMGCR） and cholesterol 7a-hydroxylase 1 （CYP7A1） was significantly up-regulated, as was the protein content of both SREBP-1 c and SREBP-2 in hepatic nuclear extracts of leptin-treated chickens. Moreover, out of 12 miRNAs targeting SREBP-1c and/or HMGCR, five were significantly up-regulated in liver of leptin-treated chicks, including gga-miR-200b and gga-miR-429, which target both SREBP-1c and ***： These results suggest that leptin in ovo decreases hatch weight, and modifies hepatic leptin secretion and lipid metabolism in newly hatched broiler chickens, possibly via microRNA-mediated gene regulation.

关键词： Broiler chickens In ovo manipulation Leptin Lipid metabolism Liver MicroRNA SREBPs