Fabrication and Properties of Mo2FeB2 Cermet Coating on Stainless Steel Surface via One-Step Forming Technology of Powder Metallurgy

Zi-Run Yang,Xin-Xing Li,Liu Zhang,Wen-Qian Yang,Wei-Bing Shi,Dan-Dan Li,Jie Cai 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.7

Mo2 FeB2 cermet coating and stainless steel substrate were integrally fabricated by one-step forming technology of powder metallurgy. The phase and microstructure of the coating and interface were analysed through X-ray diffraction and scanning electron microscopy. Microhardness, bending strength, and wear resistance were also measured by Vickers tester, the electronic universal testing machine and wear tester. The microstructure of Mo2 FeB2 cermet coating showed Mo2 FeB2 hard phase and Fe binder phase, which was uniform and dense. A compacted interface without pores or defects was formed between the cermet coating and stainless steel substrate. The formation of eutectic liquid phase and applied pressure in sintering process promoted densification of the coating. Mo2 FeB2 cermet coating presented a microhardness of 1275 HV200 , which was obviously higher than that of 316L stainless steel substrate. The results of three-point bending test and wear test showed that Mo2 FeB2 cermet coating on steel substrate maintained good metallurgical interface bonding with the substrate, and the coating exhibited high bending strength and excellent wear resistance.

Archaeal Communities in Mangrove Soil Characterized by 16S rRNA Gene Clones

Bing Yan,Kui Hong,Zi-Niu Yu 한국미생물학회 2006 The journal of microbiology Vol.44 No.5

An archaeal 16S rRNA gene library was constructed from mangrove soil. Phylogenetic analysis revealed archaea in mangrove soil including the Crenarchaeota (80.4%) and Euryarchaeota (19.6%) phyla. The archaeal community in mangrove soil appears to be a mixture of organisms found in a variety of environments with the majority being of marine origin.

Archaeal Communities in Mangrove Soil Characterized by 16S rRNA Gene Clones

Yan, Bing,Hong, Kui,Yu, Zi-Niu The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.5

An archaeal 16S rRNA gene library was constructed from mangrove soil. Phylogenetic analysis revealed archaea in mangrove soil including the Crenarchaeota (80.4%) and Euryarchaeota (19.6%) phyla. The archaeal community in mangrove soil appears to be a mixture of organisms found in a variety of environments with the majority being of marine origin.

Phthalocyanines as medicinal photosensitizers: Developments in the last five years

Li, Xingshu,Zheng, Bing-De,Peng, Xiao-Hui,Li, Song-Zi,Ying, Jia-Wen,Zhao, Yuanyuan,Huang, Jian-Dong,Yoon, Juyoung Elsevier 2019 Coordination Chemistry Reviews Vol.379 No.-

<P><B>Abstract</B></P> <P>Owing to their high extinction coefficients, long absorption wavelengths, and modification tunable photophysical and photochemical properties, phthalocyanines (Pcs) have been widely used as photosensitizers for photodynamic therapy (PDT). Advances made in the past five years on the development of Pcs as medicinal photosensitizers are reviewed and the main design considerations for medicinal applications of these substances are discussed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Recent progresses made in the development of phthalocyanines for photodynamic therapy are outlined. </LI> <LI> Representative water-soluble phthalocyanines are presented. </LI> <LI> Main targeting strategies are discussed. </LI> <LI> Future challenges are also presented. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

The morphology and mechanism of formation of SiC in C/C-SiC composites fabricated by liquid silicon infiltration

Li Zhuan,Xiao Peng,Zhu Zi-bing,Xiong Xiang 한양대학교 세라믹연구소 2010 Journal of Ceramic Processing Research Vol.11 No.3

Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) are a new type of high performance brake materials. In the present study, C/C-SiC brake composites were fabricated by the combination of chemical vapor infiltration (CVI) with liquid silicon infiltration (LSI). Results show the composite is composed of 55%C, 39% β-SiC, and 6%Si. There exist two different areas of SiC, one zone of coarse micro-β-SiC grains between 5 and 20 μm at the SiC/silicon interface, and this zone usually forms inside the porosity of the carbon fibre reinforced carbon (C/C) preform such as around the fibres and among the C/C bundles. The other zone consists of fine nano-SiC particles with dimensions of 100-800 nm at the pyrocarbon/carbon fibre interface. From these observations, reaction mechanisms governing the siliconization of porous C/C preform are proposed. After an initial reaction of carbon with liquid silicon, an initial continuous SiC layer formed on the silicon/pyrocarbon interface, and the subsequent formation of SiC is controlled by diffusion of carbon atoms and/or silicon atoms through the already formed SiC layer.

Associations of IL-10 Gene Polymorphisms with Acute Myeloid Leukemia in Hunan, China

Yao, Chen-Jiao,Du, Wei,Chen, Hai-Bing,Xiao, Sheng,Wang, Cheng-Hong,Fan, Zi-Li Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

We investigated the possible association of interleukin-10 (IL-10) single nucleotide polymorphisms (SNPs) and susceptibility to acute myeloid leukemia (AML) in 115 patients and 137 healthy controls. Genetic analysis of IL-10 SNPs at -819 and -592 was carried out with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. The IL-10 mRNA expression of AML patients and controls with different genotype was detected by real-time quantitative polymerase chain reaction (RT-PCR). Genetic analysis of IL-10 revealed that the -819AA genotype frequencies and the -819A allele frequencies in the AML group were higher than in the controls (59.1% vs 40.9%; 75.6% vs 63.9%, respectively); there were remarkable differences in -819T/C and -592A/C gene distribution (P<0.05) and the TA haploid frequencies were higher in the AML group (75.6% vs 63.9%, P<0.05). IL-10 mRNA expression in incipient AML patients was obvious higher than the non-tumor group and the remission group ($7.78{\times}10^{-3}$ vs $2.43{\times}10^{-3}$, $3.64{\times}10^{-3}$, P<0.05).The study suggested that the haploid TA and genotype TA/TA may be associated with AML in Han people in Hunan province.The IL-10 SNPs at -819 and -592 sites were associated with AML and may affect IL-10 mRNA expression in AML patients.

Sifting process of EMD and its application in rolling element bearing fault diagnosis

Hongbo Dong,Keyu Qi,Xuefeng Chen,Yanyang Zi,Zhengjia He,Bing Li 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.8

Among the vibration-based fault diagnosis methods for rolling element bearing, the shock pulse method (SPM) combined with the demodulation method is a useful quantitative technique for estimating bearing running state. However, direct demodulation often misestimates the shock value of characteristic defect frequency. To overcome this disadvantage, the vibration signal should be decomposed before demodulation. Empirical mode decomposition (EMD) can be an alternative for preprocess bearing fault signals. However, the trouble with this method’s application is that it is time-consuming. Therefore, a novel method that can improve the sifting process’s efficiency is proposed, in which only one time of cubic spline fitting is required in each sifting process. As a consequence, the time for EMD analysis can be evidently shortened and the decomposition results simultaneously maintained at a high precision. Simulations and experiments verify that the improved EMD method, combined with SPM and demodulation analysis, is efficient and accurate and can be effectively applied in engineering practice.

Automatic Detection and Classification of Rib Fractures on Thoracic CT Using Convolutional Neural Network: Accuracy and Feasibility

Zhou Qing-Qing,Wang Jiashuo,Tang Wen,Hu Zhang-Chun,Xia Zi-Yi,Xue-Song Li,Zhang Rongguo,Yin Xindao,Zhang Bing,Zhang Hong 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.7

Objective: To evaluate the performance of a convolutional neural network (CNN) model that can automatically detect and classify rib fractures, and output structured reports from computed tomography (CT) images. Materials and Methods: This study included 1079 patients (median age, 55 years; men, 718) from three hospitals, between January 2011 and January 2019, who were divided into a monocentric training set (n = 876; median age, 55 years; men, 582), five multicenter/multiparameter validation sets (n = 173; median age, 59 years; men, 118) with different slice thicknesses and image pixels, and a normal control set (n = 30; median age, 53 years; men, 18). Three classifications (fresh, healing, and old fracture) combined with fracture location (corresponding CT layers) were detected automatically and delivered in a structured report. Precision, recall, and F1-score were selected as metrics to measure the optimum CNN model. Detection/diagnosis time, precision, and sensitivity were employed to compare the diagnostic efficiency of the structured report and that of experienced radiologists. Results: A total of 25054 annotations (fresh fracture, 10089; healing fracture, 10922; old fracture, 4043) were labelled for training (18584) and validation (6470). The detection efficiency was higher for fresh fractures and healing fractures than for old fractures (F1-scores, 0.849, 0.856, 0.770, respectively, p = 0.023 for each), and the robustness of the model was good in the five multicenter/multiparameter validation sets (all mean F1-scores > 0.8 except validation set 5 [512 x 512 pixels; F1-score = 0.757]). The precision of the five radiologists improved from 80.3% to 91.1%, and the sensitivity increased from 62.4% to 86.3% with artificial intelligence-assisted diagnosis. On average, the diagnosis time of the radiologists was reduced by 73.9 seconds. Conclusion: Our CNN model for automatic rib fracture detection could assist radiologists in improving diagnostic efficiency, reducing diagnosis time and radiologists’ workload.

Novel Alkali-Stable, Cellulase-Free Xylanase from Deep-Sea Kocuria sp. Mn22

Chan Juan Li,Yu Zhi Hong,Zong Ze Shao,Ling Lin,Xiao Luo Huang,Peng Fu Liu,Gao Bing Wu,Xin Meng,Zi Duo Liu 한국미생물 · 생명공학회 2009 Journal of microbiology and biotechnology Vol.19 No.9

Heavy concrete shielding properties for carbon therapy

Jin-Long Wang,Jiade J Lu,Da-Jun Ding,Wen-Hua Jiang,Ya-Dong Li,Rui Qiu,Hui Zhang,Xiao-Zhong Wang,Huo-Sheng Ruan,Yan-Bing Teng,Xiao-Guang Wu,Yun Zheng,Zi-Hao Zhao,Kai-Zhong Liao,Huan-Cheng Mai,Xiao-Dong Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.