Microcellular foams of thermoplastic vulcanizates (TPVs) based on waste ground rubber tire powder

Zhang, Zhen Xiu,Zhang, Shu Ling,Lee, Sung Hyo,Kang, Dong Jin,Bang, Dae­Suk,Kim, Jin Kuk Elsevier 2008 Materials letters Vol.62 No.28

<P><B>Abstract</B></P><P>With the increased adoption of thermoplastic vulcanizates (TPVs) in automotive weather seal systems, the foams of TPVs present an important milestone in providing key applications such as trunk and door seals. In this study, microcellular foams of TPV based on waste ground rubber tire powder (WGRT) were investigated. In order to investigate the relationship between processing conditions and structure of TPV foams, we first prepared the thermoplastic vulcanizates of PP-g-MA/WGRT, then the samples were saturated with carbon dioxide and the saturated specimens were expanded during the pressure-quench process. The results indicated that the microcellular structure was dependent on the processing conditions. Cell size increased with saturation temperature, whereas cell density and relative density decreased. Different nucleation processes were produced with saturation pressure.</P>

Influence of Kluyveromyces marxianus on proteins, peptides, and amino acids in Lactobacillus-fermented milk

Dong-Dong Zhang,Jing-Lan Liu,Tie-Min Jiang,Lu Li,Guo-Zhen Fang,Yan-Pin Liu,Li-Jun Chen 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.3

With increasing application of yeast in fermented milk, in order to study the effect of yeast on milk protein during the fermentation process, the effects of the presence of Kluyveromyces marxianus in milk fermented by Streptococcus thermophilus and Lactobacillus bulgaricus were investigated. After fermentation, the amino acid, protein, and peptide contents were analyzed by ultra-performance liquid chromatography, two-dimensional gel electrophoresis, and liquid chromatography–mass spectrometry, respectively. After the addition of K. marxianus for fermentation, 25 protein spots changed significantly. These were mostly caseins and bovine serum proteins, and the content of total free amino acids increased by 16.30%; ten types of bioactive peptides were identified. Furthermore, the number of peptide types in milk fermented by K. marxianus increased significantly compared with milk fermented by Lactobacillus. K. marxianus is considered to promote proteometabolism in milk when added with Lactobacillus, generate flavor compounds, and improve the digestion and absorption character of milk.

Distinct bacterial community of a solid-state fermented Chinese traditional food huase sufu revealed by high-throughput sequencing

Zhang Zhen-dong,Wang Yu-rong,Xiang Fan-shu,Hou Qiang-chuan,Guo Zhuang 한국식품과학회 2021 Food Science and Biotechnology Vol.30 No.9

Sufu is a common solid-state traditional fermentedfood made from soybean. Huase sufu is a typicaltype found in several provinces of China, especially inHubei. However, little is known about the bacterial community. High-throughput sequencing technology revealedthat the dominant taxa at phylum level were: Firmicutes,Proteobacteria and Bacteroides, and at the genus levelwere: Pseudomonas, Lactococcus, Acinetobacter, etc. Additionally, LEfSe revealed that compared with the bacterialcommunity of red sufu and white sufu, the biomarkergenera for both huase sufu were Enterococcus, and Myroides. Moreover, there were twenty-eight hubs for thehuase sufu samples, and four of them were dominantgenera: Citrobacter, Myroides, Vagococcus, and Enterococcus. These results provide a new insight into ourunderstanding of the bacterial diversity of huase sufu, andwill facilitate the isolation, screening, and developmentpotential bacterial strains for production of huase sufu.

Lentivirus-mediated silencing of the PTC1 and PTC2 genes promotes recovery from spinal cord injury by activating the Hedgehog signaling pathway in a rat model

Ya-Dong Zhang,Zhong-Sheng Zhu,Dong Zhang,Zhen Zhang,Bin Ma,Shi-Chang Zhao,Feng Xue 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

This study aimed to investigate the effect of Patched-1 (PTC1) and PTC2 silencing in a rat model, on Hedgehog (Hh) pathwaymediated recovery from spinal cord injury (SCI). An analytical emphasis on the relationship between the sonic hedgehog (Shh) pathway and nerve regeneration was explored. A total of 126 rats were divided into normal, sham, SCI, negative control (NC), PTC1-RNAi, PTC2-RNAi and PTC1/PTC2-RNAi groups. The Basso, Beattie and Bresnahan (BBB) scale was employed to assess hind limb motor function. Quantitative real-time polymerase chain reaction and western blotting were performed to examine the mRNA and protein levels of PTC1, PTC2, Shh, glioma-associated oncogene homolog 1 (Gli-1), Smo and Nestin. Tissue morphology was analyzed using immunohistochemistry, and immunofluorescent staining was conducted to detect neurofilament protein 200 (NF-200) and glial fibrillary acidic protein (GFAP). The PTC1/PTC2-RNAi group displayed higher BBB scores than the SCI and NC groups. Shh, Gli-1, Smo and Nestin expression levels were elevated in the PTC1/PTC2-RNAi group. PTC1 and PTC2 mRNA and protein expression was lower in the PTC1/PTC2-RNAi group than in the normal, sham and SCI groups. Among the seven groups, the PTC1/PTC2-RNAi group had the largest positive area of NF-200 staining, whereas the SCI group exhibited a larger GFAP-positive area than both the normal and the sham groups. The Shh pathway may provide new insights into therapeutic indications and regenerative recovery tools for the treatment of SCI. Activation of the Hh signaling pathway by silencing PTC1 and PTC2 may reduce inflammation and may ultimately promote SCI recovery.

<i>Roseivivax</i> <i>roseus</i> sp. nov., an alphaproteobacterium isolated from a solar saltern soil sample

Zhang, Yu-Qin,Lee, Jae-Chan,Park, Dong-Jin,Lu, Xin-Xin,Mou, Xiao-Zhen,Kim, Chang-Jin International Union of Microbiological Societies 2014 International journal of systematic and evolutiona Vol.64 No.5

<P>A pink, Gram-stain-negative, motile, halotolerant bacterium with subpolar flagellum, designated strain BH87090<SUP>T</SUP>, was isolated from a saline soil sample collected from the south-west coastal area of South Korea (125° 58′ 58.08″ E 34° 45′ 37.32″ N). The isolate formed opaque pink to red colonies on marine agar plates at 30 °C. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, sulfoquinovosyl diacylglycerol, phosphatidylcholine and one unidentified phospholipid. The sole respiratory quinone was ubiquinone-10 (Q-10). The major cellular fatty acids were C<SUB>18 : 1</SUB>ω7<I>c</I>, C<SUB>19 : 0</SUB> cyclo ω8<I>c</I>, C<SUB>16 : 0</SUB> and 11-methyl C<SUB>18 : 1</SUB>ω7<I>c</I>. The genomic DNA G+C content was 61.8 mol%. These chemotaxonomic characteristics were all consistent with specific properties of the genus <I>Roseivivax</I>. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate affiliated to the cluster with members of the genus <I>Roseivivax</I> in the <I>Roseobacter</I> clade, which suggested that the strain belonged to the genus <I>Roseivivax</I>. However, the low 16S rRNA gene similarities (93.5–95.3 %) of strain BH87090<SUP>T</SUP> with all the members of the genus <I>Roseivivax</I> indicated that it represented a novel species of the genus <I>Roseivivax</I>. On the basis of phenotypic and genotypic data, strain BH87090<SUP>T</SUP> should be classified as a novel species of the genus <I>Roseivivax</I>. The name <I>Roseivivax roseus</I> sp. nov. is proposed, with strain BH87090<SUP>T</SUP> ( = DSM 23042<SUP>T</SUP> = KCTC 22650<SUP>T</SUP>) as the type strain.</P>

Research Progress in SiC-Based Ceramic Matrix Composites

Dong, Shaoming,Wang, Zhen,Zhou, Haijun,Kan, Yan-Mei,Zhang, Xiangyu,Ding, Yusheng,Gao, Le,Wu, Bin,Hu, Jianbao The Korean Ceramic Society 2012 한국세라믹학회지 Vol.49 No.4

SiC-based ceramic matrix composites show many advantages over their monolithic ceramic counterparts, which makes them potential candidates for applications in various fields. Depending strongly on the chemical composition and microstructure of the fiber reinforcement, matrix as well as the fiber/matrix interphase in the material, the properties of ceramic matrix composites(CMCs) are highly tailorable. In this paper, the latest progresses in the interphase design, matrix modification and fiber reinforcement decoration of CMCs are reviewed, their effects on the properties of the CMCs are introduced.

Tribological and rheological tests of core-shell typed carbonyl iron/polystyrene particle-based magnetorheological fluid

Zhang, Peng,Dong, Yu Zhen,Choi, Hyoung Jin,Lee, Chul-Hee THE KOREAN SOCIETY OF INDUSTRIAL AND ENGINEERING 2018 JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY -S Vol.68 No.-

<P><B>Abstract</B></P> <P>Polystyrene (PS) was coated on carbonyl iron (CI) particles via dispersion polymerization to produce core-shell structured CI/PS particles and adopted as magnetorheological (MR) material. Two MR fluids were prepared by dispersing CI/PS and CI particles in silicone oil. Their MR and tribological properties were investigated using a rheometer and a reciprocating friction and wear tester, respectively. Experimental data showed that tribological properties of MR fluid based on CI/PS particles are significantly enhanced compared to those of CI based MR fluid. Sedimentation problem of CI/PS MR fluid was also expected to be improved due to relatively lower density of CI/PS particles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Magnetorheological and tribological properties of MR fluids based on CI and CI/PS particles were examined. </LI> <LI> MR fluid (CI/PS) showed superior wear and frictional properties than MR fluid (CI). </LI> <LI> Friction coefficient, width and depth of wear, surface roughness, and surface topography were examined using MR fluids. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Magnetorheological (MR) behaviors and tribological properties of two kinds of MR fluids based on CI and polystyrene coated CI (CI/PS) were investigated. The MR fluid (CI/PS) showed superior wear and frictional properties than MR fluid (CI), based on the friction coefficient results, width and depth of wear, surface roughness, and surface topography.</P> <P>[DISPLAY OMISSION]</P>

Predictive and Prognostic Roles of Ribonucleotide Reductase M1 in Patients with Pancreatic Cancer Treated with Gemcitabine: A Meta-analysis

Zhang, Xiong,Jin, Fen-Shu,Zhang, Li-Guo,Chen, Rui-Xue,Zhao, Jin-Hui,Wang, Yan-Nan,Wang, En-Fu,Jiang, Zhen-Dong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.7

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.

The Investigation on the Influence of Oscillating Ambient Pressure on the Primary Breakup of Jet Spray

Zhen Zhang,Dong-hyuk Shin(신동혁) 한국항공우주학회 2019 한국항공우주학회 학술발표회 논문집 Vol.2019 No.11

Effect of CoFe₂O₄ nanoparticles on a carbonyl iron based magnetorheological suspension

Dong, Yu Zhen,Piao, Shang Hao,Zhang, Ke,Choi, Hyoung Jin Elsevier 2018 Colloids and surfaces. A, Physicochemical and engi Vol.537 No.-

<P><B>Abstract</B></P> <P>Magnetic CoFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles were successfully fabricated by a non-aqueous hydrothermal method and used as an additive in a micron-sized, carbonyl iron (CI) based-magnetorheological (MR) fluid to improve its dispersion stability and MR characteristics. The morphology and magnetic properties of CoFe<SUB>2</SUB>O<SUB>4</SUB> were demonstrated by using X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry. The results showed that CoFe<SUB>2</SUB>O<SUB>4</SUB> was synthesized successfully with a nearly spherical morphology and excellent crystalline structure. The saturation magnetization (Ms) of the CoFe<SUB>2</SUB>O<SUB>4</SUB> was also about 74.4 emu/g. The CI MR fluid was prepared by dispersing 50wt% of CI particles in silicone oil, and the CI/CoFe<SUB>2</SUB>O<SUB>4</SUB> MR fluid was prepared by adding 0.1wt% of CoFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles to the CI MR fluid. The MR characteristics of both MR fluids were tested via a rotational rheometer at various magnetic field strengths. The CI/CoFe<SUB>2</SUB>O<SUB>4</SUB> MR fluid showed enhanced MR characteristics with higher yield stress, shear viscosity, and dynamic modulus than that of the CI MR fluid. Furthermore, the dispersion stability of both MR fluids were also investigated via a Turbiscan optical analyzer system, and these results showed that the sedimentation ratio after 24h had improved by about 21%.</P> <P><B>Graphical abstract</B></P> <P>Magnetic CoFe2O4 nanoparticles were successfully fabricated by a non-aqueous hydrothermal method and used as an additive in a micron-sized, carbonyl iron (CI) based-magnetorheological (MR) fluid. The magnetorheological characteristics and dispersion stabilities for two kinds of CI based-MR fluid with and without CoFe2O4 additives were investigated.</P> <P>[DISPLAY OMISSION]</P>