Investigation of Cu Interlayer on Joint Formation of Ti/Mg Bimetal Fabricated by Liquid–Solid Compound Casting Process

Fulin Wen,Jianhua Zhao,Kaiqing Feng,Miaowang Yuan,Dengzhi Zheng,Cheng Gu,Bei Xu 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

In this paper, TC4/AZ91D bimetallic composites has been prepared by liquid–solid compound casting process adaptingvarious thickness of Cu coating. The effects of Cu coating thickness on the evolution of interface microstructures and jointmechanical properties are investigated. The results indicate that metallurgical bonded joints are obtained with Cu coatingthickness ranging from 36.7 to 51.4 μm. With the increase of Cu coating thickness, the interface microstructure evolvesfrom δ-Mg + Mg2Cueutectic structure to Mg–Cu intermetallic compound (IMC) Cu2Mg+ Mg2Cuand Mg–Al–Cu ternaryintermetallic compound. The calculation results of formation enthalpy and chemical potential of Mg–Al–Cu system suggestthat Cu element prefers to react with Mg element and formed Mg–Cu IMC. In particular, when Cu coating thickness reaches36.7 μm, the average shear strength of the bimetal reaches a maximum of 65.3 MPa. Further increasing Cu coating thicknessleads to the generation of thick Mg2CuIMC layer and Mg2Cu+ Cu2Mgmixed IMC layer which are proved to be harmful tothe shear strength of TC4/AZ91D bimetals. All the fracture surfaces of the bimetallic composites exhibite to have a brittlefracture morphology. However, the fracture location is different with each other. For Cu coating thickness of 36.7 μm, theinterface fractures at the δ-Mg + Mg2Cueutectic structure, while the interface fractures at the Cu2Mg+ Mg–Al–Cu ternaryintermetallic layers when Cu coating thickness is 44.2 μm and 51.4 μm.

Large-scale production of (2,4-DHB)nM micro-nano spheres by spray drying and their application as catalysts for ammonium perchlorate

Wen-yuan Zhao,Tong-lai Zhang,Li-nong Zhang,Li Yang,Zun-ning Zhou 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.38 No.-

A series of 2,4-dihydroxybenzoates {(2,4-DHB)nMs, M = Pb(II), Cu(II), Fe(III), Ni(II) and Co(II), n = 2 or 3}micro-nano spheres with controllable size and morphology were successfully prepared by spray dryingmethod with water or acetone as a solvent. TEM and SEM illustrated that the (2,4-DHB)nMs micro-nanospheres had core–shell or solid structure. The formation of the core–shell structure of the samples wasinterpreted in terms of the mechanism of spray drying. The results of laser particle analyzer revealed thatprecursor concentration (PC) and particle size distribution (PSD) of the samples were well fitted withpower function. The thermal decomposition of ammonium perchlorate (AP) in the presence of the (2,4-DHB)nMs micro-nano spheres, investigated by differential scanning calorimetry (DSC), showed theyeffectively lowered the decomposition temperature of AP and exhibited various catalytic performancefor AP decomposition.

Streptomyces xinghaiensis sp. nov., isolated from marine sediment.

Zhao, Xin-Qing,Li, Wen-Jun,Jiao, Wen-Ce,Li, Yan,Yuan, Wen-Jie,Zhang, Yu-Qin,Klenk, Hans-Peter,Suh, Joo-Won,Bai, Feng-Wu Society for General Microbiology 2009 International journal of systematic and evolutiona Vol.59 No.11

<P>A novel actinomycete, strain S187(T), was isolated from a marine sediment sample collected from Xinghai Bay, Dalian, China. Growth occurred on ISP medium 2 containing 0-9 % NaCl and at pH 6.0-9.0 and 10-45 degrees C. The cell wall of strain S187(T) contained the isomer ll-diaminopimelic acid as the diagnostic diamino acid. The predominant menaquinones were MK-9(H(6)) (40.8 %), MK-9(H(8)) (38.2 %) and MK-9(H(2)) (8.8 %). The major fatty acids were iso-C(16 : 0) (29.6 %), anteiso-C(15 : 0) (14.0 %) and anteiso-C(17 : 0) (11.6 %). Cells contained phosphatidylethanolamine, phosphatidylinositol, phosphatidylglycerol, phosphatidylinositol mannosides and one unknown phospholipid. The G+C content of the genomic DNA was 72.01 mol%. The 16S rRNA gene sequence of the isolate had similarities of 98.1 and 97.5 % with those of Streptomyces flavofuscus NRRL B-8036(T) (=DSM 41426(T)) and Streptomyces albiaxialis DSM 41799(T), respectively, showing that the novel strain should be assigned to the genus Streptomyces. DNA-DNA hybridizations with the two above-mentioned Streptomyces species showed 31.4 and 46.9 % relatedness, respectively. Moreover, the three strains differed in some physiological and biochemical properties. Thus, on the basis of phenotypic and genotypic analyses, it is proposed that strain S187(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces xinghaiensis sp. nov. is proposed; the type strain is S187(T) (=NRRL B-24674(T)=CCTCC AA 208049(T)=KCTC 19546(T)).</P>

The Effects of Spaceflight on Soluble Protein, Isoperoxidase, and Genomic DNA in Ural Licorice (Glycyrrhiza uralensis Fisch.)

Gao, Wen-Yuan,Fu, Rong-Zhao,Fan, Lei,Zhao, Shu-Ping,Paek, Kee-Yoeup 한국식물학회 2000 Journal of Plant Biology Vol.43 No.2

We investigated the effects of weightlessness, and ionizing radiation plus weightlessness, on changes in the levels of soluble protein, isoperoxidase, and genomic DNA, respectively, in a medicinal plant-ural licorice (Glycyrrhiza uralen-sis)-after a 15-d spaceflight in a recoverable satellite. Both the weightlessness samples (Ws) and the ionizing radiation plus weightlessness samples (IR/Ws) showed increases in soluble protein content or peroxidase activity, compared with the ground control (Gc). Moreover, the increased isoperoxidase activity for the IR/Ws group was significantly greater than for the Ws, compared with the controls. Likewise, distinctive RAPD profiles were generated among the Ws, the IR/Ws, and the Gc. The Ws and IR/Ws yielded 66 and 78 polymorphic RAPD fragments, respectively, based on bulk template DNA, along with 19 selected primers. Therefore, weightlessness alone can trigger genomic alterations, to some extent, and may even result in modulation of gene expression, whereas ionizing radiation would probably enhance the effect of weightlessness.

Physiological and microstructural responses of two Rhododendron cultivars to high temperature and low light

Yuan Li,Wen Liang,Bing Zhao 한국원예학회 2020 Horticulture, Environment, and Biotechnology Vol.61 No.3

Rhododendrons ( Rhododendron ) are ornamental plants that exhibit poor thermotolerance. To provide a theoretical basis forthe production and application of Rhododendron in summer, effects of high temperature and low light stress on the growth,physiological characteristics (including photosynthesis), and leaf structure of Rhododendron were explored. Two Rhododendroncultivars, Rh. ‘Fen Zhenzhu’ and Rh. ‘Zhuangyuan Hong’, were selected. Rhododendron plants were subjected tostress in 6-day intervals in an artifi cial climate box with 37.5, 75, 112.5, and 150 μmol m −2 s −1 photosynthetic photon fl uxat 38 °C. The leaf anatomical parameters and physiological indexes, including gas exchange parameters, relative water content,relative conductivity, chlorophyll and osmotic substance contents, malondialdehyde and hydrogen peroxide levels, andenzyme activity, of Rhododendron under high temperature and diff erent low light levels were measured. The results showedthat the combined stressors of high temperature and low light caused damage to leaves, such as loss of water, cell membranedamage, decreased net photosynthetic rate, and changes in leaf structure. Additionally, with the decreased light intensitycaused more damage, and diff erent damage mechanisms were found in diff erent cultivars and treatments.

Stability analysis of uncertain switched systems via delay partitioning

Wen-xiu Zhao,Yuan-Gong Sun 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

In this paper, by using the delay partitioning approach, new stability criteria in terms of linear matrix inequalities are established for uncertain switched linear system with delay. It is shown that the given method allows less conservative upper bound of delay as the number of delay partitioning increases. Numerical examples are also given to illustrate the main results.

XIAP Associated Factor 1 (XAF1) Represses Expression of X-linked Inhibitor of Apoptosis Protein (XIAP) and Regulates Invasion, Cell Cycle, Apoptosis, and Cisplatin Sensitivity of Ovarian Carcinoma Cells

Zhao, Wen-Jing,Deng, Bo-Ya,Wang, Xue-Mei,Miao, Yuan,Wang, Jian-Nan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Background: X-linked inhibitor of apoptosis protein (XIAP) associated factor 1 (XAF1) exhibits aberrantly low or absent expression in various human malignancies, closely associated with anti-apoptosis and overgrowth of cancer cells. However, limited attention has been directed towards the contribution of XAF1 to invasion, apoptosis, and cisplatin (DDP)-resistance of epithelial ovarian cancer (EOC) cells. This study aimed to evaluate the potential effects of XAF1 on invasion, cell cycle, apoptosis, and cisplatin-resistance by overexpressing XAF1 in SKOV-3 and SKOV-3/DDP cells. Methods and Results: The pEGFP-C1-XAF1 plasmid was transfected into SKOV-3 and SKOV-3/DDP cells, and the expression of XAF1 at both mRNA and protein levels was analyzed by reverse transcription-PCR and Western blotting. Overexpression of XAF1 suppressed XIAP expression in both SKOV-3 and SKOV-3/DDP cells. Transwell invasion assays demonstrated that XAF1 exerted a strong anti-invasive effect in XAF1-overexpressing cells. Moreover, flow cytometry analysis revealed that XAF1 overexpression arrested the cell cycle at G0/G1 phase, and cell apoptosis analysis showed that overexpression of XAF1 enhanced apoptosis of SKOV-3 and SKOV-3/DDP cells apparently by activating caspase-9 and caspase-3. Furthermore, MTT assay confirmed a dose-dependent inhibitory effect of cisplatin in the tested tumor cells, and overexpression of XAF1 increased the sensitivity of SKOV-3 and SKOV-3/DDP cells to cisplatin-mediated antiproliferative effects. Conclusions: In summary, our data indicated that overexpression of XAF1 could suppress XIAP expression, inhibit invasion, arrest cell cycle, promote apoptosis, and confer cisplatin-sensitivity in SKOV-3 and SKOV-3/DDP cells. Therefore, XAF1 may be further assessed as a potential target for the treatment of both cisplatin-resistant and non-resistant EOCs.

Thermo-mechanical stress analysis of feed-water valves in nuclear power plants

Wen-qing Li,Lei Zhao,Yang Yue,Jia-yi Wu,Zhi-jiang Jin,Jin-yuan Qian 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.3

Feed-water valves (FWVs) are used to regulate the flow rate of water entering steam generators, whichare very important devices in nuclear power plants. Due to the working environment of relatively highpressure and temperature, there is strength failure problem of valve body in some cases. Based on thethermo-fluid-solid coupling model, the valve body stress of the feed-water valve in the opening processis investigated. The flow field characteristics inside the valve and temperature change of the valve bodywith time are studied. The stress analysis of the valve body is carried out considering mechanical stressand thermal stress comprehensively. The results show that the area with relatively high-velocity areamoves gradually from the bottom of the cross section to the top of the cross section with the increase ofthe opening degree. The whole valve body reaches the same temperature of 250C at the time of 1894 s. The maximum stress of the valve body meets the design requirements by stress assessment. This workcan be referred for the design of FWVs and other similar valves.

Long Noncoding RNA FBXL19-AS1-Mediated Ulcerative Colitis-Associated Intestinal Epithelial Barrier Defect

Zhao Xun,Cui De-Jun,Yang Liu-chan,Yuan Wen-Qiang,Yan Fang 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.5

BACKGROUND: This study commenced to uncover the role of long non-coding RNA FBXL19 antisense RNA 1 (FBXL19-AS1) in the development of ulcerative colitis (UC) and its possible mechanism. METHODS: FBXL19-AS1 expression in the colonic sigmoid mucosa of UC patients was detected. A colitis model was induced in mice using 5% dextran sodium sulfate. Hematoxylin–eosin staining was performed for histopathological examination. Apoptosis was detected by Tunel staining and tissue fibrosis was detected by immunohistochemistry. Also, intestinal permeability was examined. The concentrations of inflammatory factors IL-1b and IL-18 were detected by enzyme-linked immunosorbent assay. The relationship between FBXL19-AS1, miR-339-3p and RHOB was verified by RNA immunoprecipitation assay and dual luciferase reporter assay. RESULTS: The expression of FBXL19-AS1 was increased in dextran sodium sulfate (DSS)-induced colitis mouse model. FBXL19-AS1 interference or miR-339-3p overexpression inhibited DSS-induced colonic epithelial cell apoptosis and inflammatory response, and improved intestinal epithelial barrier defects, thereby ameliorating DSS-induced colitis injury in mice. FBXL19-AS1 sponged miR-339-3p while miR-339-3p targeted RHOB. Overexpression of RHOB reversed the protective effect of inhibition of FBXL19-AS1 on DSS-induced colitis in mice. CONCLUSION: FBXL19-AS1 reduces miR-339-3p-mediated targeting of RHOB and aggravates intestinal epithelial barrier defect in DSS-induced colitis in mice.

Association of GSTP1 and RRM1 Polymorphisms with the Response and Toxicity of Gemcitabine-cisplatin Combination Chemotherapy in Chinese Patients with Non-small Cell Lung Cancer

Yuan, Zhi-Jun,Zhou, Wen-Wu,Liu, Wei,Wu, Bai-Ping,Zhao, Jin,Wu, Wei,He, Yi,Yang, Shuo,Su, Jing,Luo, Yi Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Background: Previous studies showed that genetic polymorphisms of glutathione S-transferase P1 (GSTP1) were involved in glutathione metabolism and genetic polymorphisms of ribonucleotide reductase (RRM1) were correlated with DNA synthesis. Here we explored the effects of these polymorphisms on the chemosensitivity and clinical outcome in Chinese non-small cell lung cancer (NSCLC) patients treated with gemcitabine-cisplatin regimens. Materials and Methods: DNA sequencing was used to evaluate genetic polymorphisms of GSTP1 Ile105Val and RRM1 C37A-T524C in 47 NSCLC patients treated with gemcitabine-cisplatin regimens. Clinical response was evaluated according to RECIST criteria after 2 cycles of chemotherapy and toxicity was assessed by 1979 WHO criteria (acute and subacute toxicity graduation criteria in chemotherapeutic agents). Results: There was no statistical significance between sensitive and non-sensitive groups regarding the genotype frequency distribution of GSTP1 Ile105Val polymorphism (p>0.05). But for RRM1 C37A-T524C genotype, sensitive group had higher proportion of high effective genotype than non-sensitive group (p=0.009). And according to the joint detection of GSTP1 Ile105Val and RRM1 C37A-T524C polymorphisms, the proportion of type A (A/A + high effective genotype) was significantly higher in sensitive group than in non-sensitive group (p=0.009). Toxicity showed no correlation with the genotypes between two groups (p>0.05). Conclusions: Compared with single detection of genetic polymorphisms of GSTP1 Ile105Val or RRM1 C37A-T524C, joint detection of both may be more helpful for patients with NSCLC to receive gemcitabine-cisplatin regimens as the first-line chemotherapy. Especially, genetic polymorphism of RRM1 is more likely to be used as an important biomarker to predict the response and toxicity of gemcitabine-cisplatin combination chemotherapy in NSCLC.