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Nanchang, China

Guo S.F.,Southwest University | Zhang H.J.,Chongqing University | Liu Z.,Hong Kong Polytechnic University | Chen W.,Hong Kong Polytechnic University | Xie S.F.,Jiangxi Academy of science
Electrochemistry Communications | Year: 2012

It is well recognized that amorphous alloys usually offer much higher resistance to corrosion over their conventional counterparts in most aqueous solutions. Whereas, in this work, we reported an anomalous corrosion resistance of an arc melting Zr 62.3Cu 22.5Fe 4.9Al 6.8Ag 3.5 crystalline alloy, which was superior to that of the same composition in glassy state in simulated seawater. It was revealed that the easy formation of a highly protective Zr- and Al-enriched oxide layer at the surface of the crystalline alloy is responsible for the extremely high corrosion resistance. The current finding not only presents an excellent alloy candidate for potential application in seawater but provides a new insight into the understanding of corrosion behavior of amorphous/crystalline alloys in demanding corrosive media. © 2012 Elsevier B.V.

Hua X.,Nanchang University | Hua X.,Jiangxi Academy of science | Li Y.,Nanchang University | Min Z.,China Electronics Technology Group Corporation
Journal of Alloys and Compounds | Year: 2014

Intermetallic compounds (IMCs) formations of Bi-containing Sn0.7Cu/Cu interface were studied for soldering at four levels of temperatures (240, 260, 280 and 300 °C) and isothermal aging at 150 °C. It was found that addition of Bi into the Sn0.7Cu eutectic solder caused the excessive formations of IMCs during the soldering reaction and thereafter in aging condition. The interfacial IMC layer was composed of Cu60- Sn5 and Cu3Sn layers after liquid soldering for Sn0.7Cu/Cu, Sn0.7Cu0.7Bi/Cu and Sn0.7Cu1.3Bi/Cu joints. With the increasing soldering temperature, the thickness of IMC layers (including Cu6Sn5 and Cu3Sn IMCs) increased linearly. After various days of aging, a comparatively planar IMC layer at the solder/Cu interface was observed than that of the as-soldered joints. The growth of IMC layer during aging for Sn0.7Cu, Sn0.7Cu0.7Bi and Sn0.7Cu1.3Bi solders followed the diffusion control mechanism. And the interfacial IMC layers were thicker with higher Bi content in solder alloy since the Bi could result in more chemical bonds between Cu atoms or between Cu and Sn atoms to be broken, which made more Cu and Sn atoms activated. © 2013 Elsevier B.V. All rights reserved.

Jiang Y.,Nanchang University | Du Y.,Nanchang University | Zhu X.,Nanchang University | Xiong H.,Nanchang University | And 3 more authors.
Carbohydrate Polymers | Year: 2012

The physicochemical properties of the pectins extracted from Akebia trifoliata var. australis peel with hydrochloric acid and citric acid, namely HEP and CEP, were evaluated as compared with citrus pectin (CP). X-ray diffraction confirmed that CP had more well defined crystal than HEP and CEP. The DE values of HEP, CEP and CP were 59.46%, 76.64% and 71.03%, respectively. CP exhibited the highest viscosity-average molecular weight of 64,848 Da, followed by HEP (45,353 Da) and CEP (28,877 Da). In general, the emulsion activity of HEP and CEP increased as oil concentration was increased, while HEP showed the strongest emulsion activity among the three pectins. Textural analysis demonstrated that the gelling properties of three pectins decreased with increase in pH, and CP displayed superiority in hardness (9.03 g), while CEP was the poorest (1.45 g). All results suggested that A. trifoliata var. australis had the potential in producing pectin for commercial food industry application. © 2011 Elsevier Ltd. All rights reserved.

Liu Y.,Nanchang University | Shao S.,Nanchang University | Xu C.,Nanchang University | Yang X.,Nanchang University | Lu D.,Jiangxi Academy of science
Materials Letters | Year: 2012

The wear behavior of Mg-1.5Zn-0.15Gd alloy before and after cryogenic treatment (CT) has been investigated by dry sliding wear test and scanning electron microscope (SEM). The experimental result shows that the wear resistance of the alloys has been significantly improved after CT. The observation worn surface indicates that abrasive wear is the main wear mechanism of Mg-1.5Zn-0.15Gd alloy. The friction coefficient and wear rate decrease with the increase of CT duration, which is attributed to the increase of volume fraction of the secondary phase particles and its refinement due to the CT. Moreover, the alloy after cryogenic treatment exhibits a much smoother worn surface. The wear mechanism of the alloy before and after CT has been discussed. © 2012 Elsevier B.V. All rights reserved.

Chen Y.,Nanjing Forestry University | Chen Y.,Jiangxi Academy of science
PloS one | Year: 2014

BACKGROUND: Variegation in flower color is commonly observed in many plant species and also occurs on ornamental peaches (Prunus persica f. versicolor [Sieb.] Voss). Variegated plants are highly valuable in the floricultural market. To gain a global perspective on genes differentially expressed in variegated peach flowers, we performed large-scale transcriptome sequencing of white and red petals separately collected from a variegated peach tree.RESULTS: A total of 1,556,597 high-quality reads were obtained, with an average read length of 445 bp. The ESTs were assembled into 16,530 contigs and 42,050 singletons. The resulting unigenes covered about 60% of total predicted genes in the peach genome. These unigenes were further subjected to functional annotation and biochemical pathway analysis. Digital expression analysis identified a total of 514 genes differentially expressed between red and white flower petals. Since peach flower coloration is determined by the expression and regulation of structural genes relevant to flavonoid biosynthesis, a detailed examination detected four key structural genes, including C4H, CHS, CHI and F3H, expressed at a significantly higher level in red than in white petal. Except for the structural genes, we also detected 11 differentially expressed regulatory genes relating to flavonoid biosynthesis. Using the differentially expressed structural genes as the test objects, we validated the digital expression results by using quantitative real-time PCR, and the differential expression of C4H, CHS and F3H were confirmed.CONCLUSION: In this study, we generated a large EST collection from flower petals of a variegated peach. By digital expression analysis, we identified an informative list of candidate genes associated with variegation in peach flowers, which offered a unique opportunity to uncover the genetic mechanisms underlying flower color variegation.

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