Laser Joining of Ti3Al-Based Alloy to Ni-Based Superalloy using a Titanium Interlayer

Xiao-Long Cai,Da-Qian Sun,Hong-Mei Li,Hong-Ling Guo,Yan Zhang,Ying-ying Che 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.8

Joining Ti3Al-based alloy to Ni-based superalloy is of great interest for applications in the aerospace fields. Direct welding of these two materials was very difficult and the joint usually fractured during laser welding which cannot form an effective welding joint. In this work, a pure titanium interlayer with a thickness of 0.4 mm was used between the base metals. The results indicated that the addition of titanium interlayer has a great effect on the joint performance. No macrocracks were found through the whole joint. The average room-temperature tensile strength of the joint with titanium was 177 MPa which still much lower than the two base metals. The weak link of the dissimilar joint was the Ti3Al/weld interface. The presence of Ti2Ni, α2-Ti3Al and AlNi2Ti brittle intermetallic compounds in the Ti3Al/weld interface deteriorated the joint properties.

A Systematic Review of Risk Factors for Brain Metastases and Value of Prophylactic Cranial Irradiation in Non-Small Cell Lung Cancer

Sun, Dian-Shui,Hu, Li-Kuan,Cai, Ying,Li, Xiao-Mei,Ye, Lan,Hou, Hua-Ying,Wang, Cui-Hong,Jiang, Yu-Hua Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Background: The incidence of brain metastases (BM) varies in patients with non-small cell lung cancer (NSCLC), calls into question the value of prophylactic cranial irradiation (PCI). It is possible that clinicopathologic characteristics are associated with the development of BM, but these have yet to be identified in detail. Thus, we conducted the present meta-analysis on risk factors for BM and the value of PCI in patients with NSCLC. Methods: Eligible data were extracted and the risk factors for BM and the value of PCI in patients with NSCLC were analyzed by calculating the pooled odds ratio (OR). Heterogeneity was detected using Q and I-squared statistics, and publication bias was tested by funnel plots and Egger's test. Results: Six randomized controlled trials with a focus on the value of PCI and 13 eligible studies with a focus on risk factors for BM were included. PCI significantly reduced the incidence of BM in patients with NSCLC (p=0.000, pooled OR=0.34, 95% confidence interval = 0.37-0.59). Compared with non-squamous cell carcinoma, squamous cell carcinoma was associated with a low incidence of BM in patients with NSCLC (p=0.000, pooled OR=0.47, 95% confidence interval =0.34-0.65). The funnel plot and Egger's test suggested that there was no publication bias in the current meta-analysis. Conclusions: This meta-analysis provides statistical evidence that compared with non-squamous cell carcinoma, squamous cell carcinoma can be used as a predictor for BM in patients with NSCLC, and PCI might reduce the incidence of BM in patients with NSCLC, but does not provide a survival benefit.

The complete mitochondrial genome sequence of the little grebe (Tachybaptus ruficollis)

Mei-dong Jing,Ling Huang,Yi-cheng Wang,Yi Zou,Xiao-min Sun,Jie Gong 한국유전학회 2017 Genes & Genomics Vol.39 No.1

Podicipediformes comprises one family (Podicipedidae) including 6 genera, 22 species, and the phylogenetic placement of this order was still in debate. In this study, we sequenced the complete mitochondrial genome (mitogenome) of little grebe (Tachybaptus ruficollis) in Podicipediformes, and explored the phylogenetic position of this order with mitogenome sequences of 21 species from ten families in seven orders. The genome was 16,688 bp in length, and contained 37 genes typical to avian mitogenomes and one control region. The gene organization and characters were similar with other two mitogenomes available in Podicipediformes to date. Phylogenetic tree was constructed with Bayesian method based on mitogenome sequences excluding the control regions. The results supported the closest relationship between Podicipediformes and Phoenicopteriformes, and the topology of our tree was generally similar with the conclusions of previous molecular systematic investigations. Our results furtherly proved the validity of mitogenome data in taxonomic and phylogenetic studies.

Two New Coumarin Glucosides from the Roots of Angelica apaensis and Their Anti-Platelet Aggregation Activity

Xiao, Wei-Lie,Shen, Yun-Heng,Niu, Xue-Mei,Sun, Han-Dong,Li, Sheng-Hong 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.7

Two new coumarin glucosides, $11-O-{\beta}-D-glucopyranosyl$ thamnosmonin (1) and $12-O-{\beta}-D-glucopyranosyl$ gosferol (2), were isolated from the roots of Angelica apaensis. Their structures were elucidated spectroscopically. Both compounds showed weak inhibitory effects on rabbit platelet aggregation induced by PAF, AA and APD.

Association Between XRCC1 Gene Polymorphisms and Risk of Glioma Development: A Meta-analysis

Sun, Jian-Ying,Zhang, Chun-Yang,Zhang, Zhen-Jun,Dong, Yan-Fang,Zhang, An-Long,Wang, Zhi-Wei,Mei, Xiao-Long Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Objective: Previous studies of the association between X-ray cross-complementing group 1 (XRCC1) gene polymorphisms and the gliomas risk have yielded conflicting results, and thus a meta-analysis was performed to provide a more accurate estimation. Methods: A computerized literature search of 5 electronic databases was conducted to identify the relevant studies. Fixed or random effect models were selected based on the heterogeneity test. Publication bias was estimated using Begg's funnel plots and Egger's regression test. Results: A total of 11 studies (3,810 cases and 6,079 controls), 7 studies (2,928 cases and 5,048 controls), and 4 studies (1,461 cases and 2,593 controls) were finally included in the analyses of the association between XRCC1 Arg399Gln, Arg194Trp, and Arg280His polymorphisms and glioma risk, respectively. The pooled results showed that GlnGln carriage was associated with moderately increased risk of gliomas in Asians (GlnGln vs. ArgArg, OR=1.490, 95%CI 1.031-2.153; GlnGln/ArgGln vs. ArgArg, OR=1.321, 95%CI 1.037-1.684), whereas a marginal association was revealed in Caucasians. For the Arg194Trp polymorphism, although a significant association was shown in the homozygous genotype comparisons (TrpTrp vs. ArgArg, OR = 2.209, 95%CI 1.398-2.945), no significant link was found on subgroup analysis stratified by ethnicity. With regard to the Arg280His polymorphism, no significant association was found in each comparison. No particular study was found to significantly influence the pooled results, and no potential publication bias was detected. Conclusions: This meta-analysis suggested that the XRCC1 Arg399Gln polymorphism is moderately associated with increased risk of gliomas in Asians, while Arg194Trp and Arg280His polymorphisms demonstrated no significant influence. Due to the limited studies and the potential confounders, further studies are needed to confirm these results.

Molecular Cloning and Characterization of a Novel Cold-Adapted Family VIII Esterase from a Biogas Slurry Metagenomic Library

( Xiao Jie Cheng ),( Xu Ming Wang ),( Tian Lei Qiu ),( Mei Yuan ),( Jiang Uang Sun ),( Jun Lian Gao ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.11

A novel esterase gene, est01, was successfully unearthed from a biogas digester microbiota metagenomic library. The 1,194 bp est01 gene encodes a protein of 44,804 Da (designated Est01). The amino acid sequence of Est01 shows only moderate (33%) identity to a lipase/ esterase. Phylogenetic analysis and biochemical characterization confirmed that Est01 is a new member of family VIII esterases. The purified Est01 from recombinant Escherichia coli BL21 (DE3) showed high hydrolytic activity against short-chain fatty acid esters, suggesting that it is a typical carboxylesterase rather than a lipase. Furthermore, the Est01 was even active at 10°C (43% activity remained), with the optimal temperature at 20°C, and had a broad pH range from 5.0 to 10.0, with the optimal pH of 8.0. These properties suggest that Est01 is a cold-adaptive esterase and could have good potential for low-temperature hydrolysis application.

Intermedins A and B; New Metabolites from Schisandra propinqua var. intermedia

Hong-Mei Li,Chun Lei,Yong-Ming Luo,Xiao-Nian Li,Xiao-Lei Li,Jian-Xin Pu,San-Yun Zhou,Rong-Tao Li,Han-Dong Sun 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.6

A new dibenzocyclooctadiene lignan, intermedin A (1), and a new natural bisabolane sesquiterpenoid, intermedin B (2), were isolated from the aerial parts of Schisandra propinqua var. intermedia. Their structures were elucidated on the basis of extensive spectroscopical analysis.

Diversity and composition of microbiota during fermentation of traditional Nuodeng ham

Zhang Xiao-mei,Dang Xi-jun,Wang Yuan-bing,Sun Tao,Wang Yao,Yu Hong,Yang Wu-song 한국미생물학회 2021 The journal of microbiology Vol.59 No.1

The microbial community is one of the most important factors in shaping the characteristics of fermented food. Nuodeng ham, traditionally produced and subjected to 1–4 years of fermentation, is a dry fermented food product with cultural and economic significance to locals in southwestern China. In this study, we aimed to characterize the microbiota and physicochemical profiles of Nuodeng ham across different stages of fermentation. Ham samples from each of the four years were analyzed by sequencing bacterial 16S rRNA gene and fungal internal transcribed spacer sequence, in order to characterize the diversity and composition of their microflora. A total of 2,679,483 bacterial and 2,983,234 fungal sequences of high quality were obtained and assigned to 514 and 57 genera, respectively. Among these microbes, Staphylococcus and Candida were the most abundant genera observed in the ham samples, though samples from different years showed differences in their microbial abundance. Results of physicochemical properties (pH, water, amino acid, NaCl, nitrate and nitrite contents, and the composition of volatile compounds) revealed differences among the ham samples in the composition of volatile compounds, especially in the third year samples, in which no nitrite was detected. These results suggest that the structure and diversity of microbial communities significantly differed across different stages of fermentation. Moreover, the third year hams exhibits a unique and balanced microbial community, which might contribute to the special flavor in the green and safe food products. Thus, our study lends insights into the production of high quality Nuodeng ham.

ent-Abietane Diterpenoids from Isodon xerophilus

Li Mei Li,Jian Xin Pu,Wei Lie Xiao,Han-Dong Sun 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.6

Three new ent-abietanoids, named xerophilusins XIV–XVI, and four known analogues, as well as four known chemical constituents were isolated from the leaves of Isodon xerophilus. Their structures were elucidated by extensive spectroscopic studies, and comparison with literature data. In addition, the cytotoxic activity of the ent-abietanoids against chronic myelogenous leukemia (K562), stomach adenocarcinoma (MKN45), and hepatocellular carcinoma (HepG2) human cell lines was investigated and no activities were observed.

Influence mechanism of the compositions in coal-fired flue gas on Hg0 oxidation over commercial SCR catalyst

Jian Mei,Pengxiang Sun,Xin Xiao,Qi Zhang,Hui Zhao,Yongfu Guo,Shijian Yang 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.75 No.-

Optimizing the performance of commercial SCR catalyst (i.e., V2O5–WO3/TiO2) for Hg0 oxidationremained stagnant as the influence mechanism of the compositions offlue gas on Hg0 oxidation wasunclear. In this work, the mechanism of Hg0 oxidation and the influence mechanism of the compositionsofflue gas on Hg0 oxidation over V2O5–WO3/TiO2 were investigated. The reaction orders of Hg0 oxidationover V2O5–WO3/TiO2 in regard to both the concentrations of Hg0 and HCl in gas phase wereapproximately 0. Hence, Hg0 oxidation over V2O5–WO3/TiO2 primarily followed the Langmuir–Hinshelwood mechanism, and the elementary reactions of Hg0 oxidation primarily involved the physicaladsorption of Hg0, the formation of Cl* radial, and the reaction of physically adsorbed Hg0 and Cl* radial. SO2, NO, H2O, and NH3 not only restrained the Cl* radial formation but also disturbed the reaction ofphysically adsorbed Hg0 and Cl* radial. Meanwhile, the physical adsorption of Hg0 was restrained by bothH2O and NH3. Hence, Hg0 oxidation over V2O5–WO3/TiO2 was obviously restrained when SO2, NO, H2O,and NH3 were present influe gas.