Influence of Microstructure and Mechanical Properties on Formability in High Strain Rate Rolled AZ31 Magnesium Alloy Sheets

Fubao Liu,Xiao Liu,Biwu Zhu,Hui Yang,Gang Xiao,Mingyue Hu 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.6

High strain-rate rolling (≥ 10 s−1) has been successfully employed to produce AZ31 magnesium alloy sheets to a high reductionof 82% with a fine grain structure in a single pass. The rolled sheets inevitably undertake various forming processessuch as press and deep forming in the fabrication stage. To investigate the formability, the Erichsen tests were carried out onhigh strain rate rolled AZ31 magnesium alloy sheets at room temperature. The relationship among mechanical properties,microstructure and formability were investigated. The crack behavior during Erichsen tests was also studied. It was foundthat the formability was related to the lowest in-plane tensile strengthen and dislocation density of initial microstructure. The competitive relationship between micro-crack and twinning/shear bands would also influence the formability of highstrain rate rolled magnesium alloy sheets. Deformed shear band with substaintial twins prohibits the crack extension andenhances strengthen of materials in front of crack tip.

"五四"何以失精神

劉慧軍 한국중국문화학회 2000 中國學論叢 Vol.9 No.-

5·4운동은 중국 역사상 위대한 사상변혁운동이다. 5·4운동이 제창한 "立人"사상은 당시뿐만 아니라 현재에 있어서도 중국문화의 발전과 변화에 중요한 의의를 지니고 있다. 그러나 여러 가지 원인 때문에 5·4정신은 잊혀졌다. 본고는 정치와 문화적 측면에서 5·4정신이 잊혀지게 된 원인을 검토한 바, 다음 3가지가 주된 원인으로 작용하였다고 분석하였다. 첫째, 중국전통문화의 뿌리가 확고하여 민주사상이 단시간 내에 확립될 수 없었다. 둘째, 정치의 막강한 흡인력이 신문화운동 발전에 영향을 미쳐 지식인이 문화적 사고를 포기하여, 중국의 사상계몽이 시작되자마자 중단되었다. 셋째, 5·4운동 후 권력자의 남용이 5·4정신을 잊혀지게 하는 중요한 원인이 되었다.

Array-based Nano-amplification Technique Was Applied in Detection of Hepatitis E Virus

Liu, Hui-Hui,Cao, Xuan,Yang, Yong,Liu, Ming-Gui,Wang, Ye-Fu Korean Society for Biochemistry and Molecular Biol 2006 Journal of biochemistry and molecular biology Vol.39 No.3

A rapid method for the detection of Hepatitis E Virus (HEV) was developed by utilizing nano-gold labeled oligonucleotide probes, silver stain enhancement and the microarray technique. The 5'-end -$NH_2$ modified oligonucleotide probes were immobilized on the surface of the chip base as the capture probe. The detection probe was made of the 3'-end -SH modified oligonucleotide probe and nano-gold colloid. The optimal concentrations of these two probes were determined. To test the detection sensitivity and specificity of this technique, a conservative fragment of the virus RNA was amplified by the RT-PCR/PCR one step amplification. The cDNA was hybridized with the capture probes and the detection probes on microarray. The detection signal was amplified by silver stain enhancement and could be identified by naked eyes. 100 fM of amplicon could be detected out on the microarray. As the results, preparation of nano-gold was improved and faster. Development time also was shortened to 2 min. Thus, considering high efficiency, low cost, good specificity and high sensitivity, this technique is alternative for the detection of HEV.

Array-based Nano-amplification Technique Was Applied in Detection of Hepatitis E Virus

( Hui Hui Liu ),( Xuan Cao ),( Yong Yang ),( Ming Gui Liu ),( Ye Fu Wang ) 생화학분자생물학회 2006 BMB Reports Vol.39 No.3

Mitochondrial citrate accumulation drives alveolar epithelial cell necroptosis in lipopolysaccharide-induced acute lung injury

Yang Hui-Hui,Jiang Hui-Ling,Tao Jia-Hao,Zhang Chen-Yu,Xiong Jian-Bing,Yang Jin-Tong,Liu Yu-Biao,Zhong Wen-Jing,Guan Xin-Xin,Duan Jia-Xi,Zhang Yan-Feng,Liu Shao-Kun,Jiang Jian-Xin,Zhou Yong,Guan Cha-Xi 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Necroptosis is the major cause of death in alveolar epithelial cells (AECs) during acute lung injury (ALI). Here, we report a previously unrecognized mechanism for necroptosis. We found an accumulation of mitochondrial citrate (citratemt) in lipopolysaccharide (LPS)-treated AECs because of the downregulation of Idh3α and citrate carrier (CIC, also known as Slc25a1). shRNA- or inhibitor–mediated inhibition of Idh3α and Slc25a1 induced citratemt accumulation and necroptosis in vitro. Mice with AEC-specific Idh3α and Slc25a1 deficiency exhibited exacerbated lung injury and AEC necroptosis. Interestingly, the overexpression of Idh3α and Slc25a1 decreased citratemt levels and rescued AECs from necroptosis. Mechanistically, citratemt accumulation induced mitochondrial fission and excessive mitophagy in AECs. Furthermore, citratemt directly interacted with FUN14 domain-containing protein 1 (FUNDC1) and promoted the interaction of FUNDC1 with dynamin-related protein 1 (DRP1), leading to excessive mitophagy-mediated necroptosis and thereby initiating and promoting ALI. Importantly, necroptosis induced by citratemt accumulation was inhibited in FUNDC1-knockout AECs. We show that citratemt accumulation is a novel target for protection against ALI involving necroptosis.

De novo assembly of the transcriptome for Greenbug (Schizaphis graminum Rondani) and analysis on insecticide resistance-related genes

Jun-Jie LIU,Liu-Yang LU,Hui-Hui LIU,Ya-She LI,Xu SU,Bai-Zhong ZHANG,Xi-Ling CHEN 한국곤충학회 2019 Entomological Research Vol.49 No.8

The greenbug, Schizaphis graminum Rondani is a major pest species of wheat crops. In this study, a transcriptome sequencing, and the expression of the 12 genes related to insecticide resistance were conducted in S. graminum. The sequencing and subsequent bioinformatics analysis outputed 46,593 unigenes, among which 28,289 unigenes were annotated to corresponding functions by blasting with high homologous genes in database, giving annotation rate of 60.72%. To gain insight into the mechanism of insecticide resistance, the expression of the 12 genes related to insecticide resistance for S. graminum was investigated. The expression level of aminopeptidase N (AN), cytochrome P450 (CYP), acetylcholinesterase 1 (AC), catalase (CAT), cytochrome c oxidas (CCC), GABA receptor (GABA), glutathione S-transferase (GST) were highest in the apterous nymphs among different developmental stages; The expression level of AN, CBL, CYP, CA, SD, and GST were relatively more abundant in the abdomen compared to head and throax. The results could give out the key information about the relationship between the expression of these genes in different developmental stages, tissues, treatments and metabolism of insecticides. These genes that were co-up-regulated significantly in third instar nymphs of S. graminum induced by imidacloprid, were consistent with their putative involvement in insecticide resistance. This provides most comprehensive transcriptome data for S. graminum to further study and managenment.

Study on a stretchable, fiber-shaped, and TiO₂ nanowire array-based dye-sensitized solar cell with electrochemical impedance spectroscopy method

Liu, Guicheng,Wang, Hui,Wang, Manxiang,Liu, Wenbing,Anugrah Ardhi, Ryanda Enggar,Zou, Dechun,Lee, Joong Kee Elsevier 2018 ELECTROCHIMICA ACTA Vol.267 No.-

<P><B>Abstract</B></P> <P>A spring-like Ti@TiO<SUB>2</SUB> nanowire array wire has been introduced into a stretchable fiber-shaped dye-sensitized solar cell (FDSSC) as a photoanode to achieve high flexibility and elasticity in this paper. Given the TiO<SUB>2</SUB> layer, which was prepared by a hydrothermal reaction in the optimized NaOH concentration of 2.5 mol L<SUP>−1</SUP>, with a 1D structure and high adhesion between the TiO<SUB>2</SUB> nanowire array and the Ti wire substrate, the novel FDSSC still possesses photoelectric conversion efficiency retention rates of approximately 97.00% and 95.95% after bending to a radius of 1.0 cm and stretching to 100% strain, respectively. EIS result shows the degradation mechanism of the FDSSC photoelectric performance: the bending test leads to more terrible electron combination; the stretching operation increases the internal resistance and charge-transfer resistance at the counter electrode. Moreover, it's worth noting that, this is the first time to show a 100%-stretching degree in the FDSSC research field so far.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A fiber-shaped, stretchable, TiO<SUB>2</SUB> nanowire array-based DSSC was reported firstly. </LI> <LI> Using EIS analysis method to analyse effect of bending and stretching on FDSSC performance. </LI> <LI> Photoelectric conversion efficiency retention rate of 95.95% after stretching to 100% strain. </LI> <LI> High flexibility with 97.00% performance retention rate at bending radius of 1 cm. </LI> </UL> </P>

A Hausdorff Distance Based Image Registration Algorithm

Liu Hui,Zhang Zhichun,Wei Dong 보안공학연구지원센터(IJSIP) 2015 International Journal of Signal Processing, Image Vol.8 No.1

Hausdorff distance is a common image registration method that is based on the edge features in the image. Theoretically, using Hausdorff distance method, the rotation, scaling and translation factors of the image can be obtained by searching the four-dimensional space that includes one rotation factor, one scaling factor and two translation factors. However, each additional factor means that the dimension degree of searching space is increased one more. The searching speed will be greatly reduced with the increasing of dimension degree. This paper presents a new image registration algorithm that combines the Hausdorff distance with the angle transform. Using this method, the translation factors can be obtained by Hausdorff distance and the angle transform can be directly computed. There is three step for finishing the image registration through the new method. Firstly, discrete Canny edge detection is used on the image. Secondly, the linear features of the image is directly used to calculate the rotation angle parameter. Then Hausdorff distance is used searching in two-dimensional space for getting the translation parameters of the image. Simulation results verified the correctness and validity of the paper method.

Design of 3-electrode system for <i>in situ</i> monitoring direct methanol fuel cells during long-time running test at high temperature

Liu, Guicheng,Li, Xinyang,Wang, Hui,Liu, Xiuying,Chen, Ming,Woo, Jae Young,Kim, Ji Young,Wang, Xindong,Lee, Joong Kee Elsevier 2017 APPLIED ENERGY Vol.197 No.-

<P>To understand the effect mechanisms of long-time running and high operation temperature on performance of the direct methanol fuel cell (DMFC) more clearly and directly, in this paper, a new design of 3-electrode system with a solution-type salt bridge has been developed to distinguish the integral polarization into anodic and cathodic polarizations at various temperatures and explore the attenuation mechanism by in situ monitoring the potential of anode during long-time running process at 80 degrees C, for the first time. The results indicate that the optimized 3-electrode system consists of a standard calomel electrode (SCE) and a solution-type salt bridge placed in the anode hole filled by 0.5 mol L-1 H2SO4 solution. By utilization of the 3-electrode system, the effect mechanisms of the running temperature and time on electrochemical parameters of the DMFC have been found: (1) The increasing operation temperature improves cathodic performance more significantly than that of anode; (2) the attenuation of fuel cell performance mainly comes from that of anode during the 20-h running test at 80 degrees C, resulting from the sharp drop of electrochemical active surface area of anode. More important, the new 3-electrode system has simplified the detection equipment and reduced the operating difficulty in a practical application for DMFCs, resulting in its portability. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Nickel hydroxide/chemical vapor deposition-grown graphene/nickel hydroxide/nickel foam hybrid electrode for high performance supercapacitors

Liu, Shude,Yin, Ying,San Hui, Kwan,Hui, Kwun Nam,Lee, Su Chan,Chan Jun, Seong Elsevier 2019 ELECTROCHIMICA ACTA Vol.297 No.-

<P><B>Abstract</B></P> <P>Rational design of electrode structures has been recognized as an effective strategy to improve the electrochemical performance of electrode materials. Herein, we demonstrate an integrated electrode in which nickel hydroxide (Ni(OH)<SUB>2</SUB>) nanosheets are deposited on both sides of chemical vapor deposition-grown graphene on Ni foam, which not only effectively optimizes electrical conductivity of Ni(OH)<SUB>2</SUB>, but also accommodates the structural deformation associated with the large volume change upon cycling. The synthesized Ni(OH)<SUB>2</SUB>/graphene/Ni(OH)<SUB>2</SUB>/Ni foam electrode exhibits a high specific capacity of 991 C g<SUP>−1</SUP> at a current density of 1 A g<SUP>−1</SUP>, which is higher than the theoretical specific capacity of additive sum of Ni(OH)<SUB>2</SUB> and graphene, and retains 95.4% of the initial capacity after 5000 cycles. A hybrid supercapacitor is constructed by using Ni(OH)<SUB>2</SUB>/graphene/Ni(OH)<SUB>2</SUB>/Ni foam as the positive electrode and activated carbon on Ni foam as the negative electrode, which achieves a maximum energy density of 49.5 W h kg<SUP>−1</SUP> at a power density of 750 W kg<SUP>−1</SUP>, and excellent cycling lifespans with 89.3% retention after 10000 cycles at 10 A g<SUP>−1</SUP>.</P>