IN SITU UNZIPPING OF CARBON NANOTUBES TO FORM GRAPHENE NANORIBBONS

YONG-SHENG ZHOU,PAN JIN,TENG GUO,YING-CHUN ZHU,GAO-HUI DU,BING-SHE XU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.1

We report the one step facile synthesis of graphene nanoribbons (GNRs) by unzipping carbonnanotubes (CNTs) from glucose (C 6 H 12 O 6 ) precursor, using a simple chemical vapor depositionmethod. Some nanotubes are partially cut resulting in a GNR – CNT hybrid whereas others arefully cut to form GNRs. The average length of GNRs achieved by this method is typically in therange of 1 – 10 ? m. The formation of GNRs is ascribed to the in situ oxygen-driven unzipping ofCNTs. The process is free from aggressive oxidants and utilizes the in situ unzipping. Thismethod o®ers an alternative approach for making GNRs, compared to previously used techniquesto synthesize GNRs.

MicroRNA-214 Regulates the Acquired Resistance to Gefitinib via the PTEN/AKT Pathway in EGFR-mutant Cell Lines

Wang, Yong-Sheng,Wang, Yin-Hua,Xia, Hong-Ping,Zhou, Song-Wen,Schmid-Bindert, Gerald,Zhou, Cai-Cun Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Patients with non-small cell lung cancer (NSCLC) who have activating epidermal growth factor receptor (EGFR) mutations derive clinical benefit from treatment with EGFR-tyrosine kinase inhibitors ((EGFR-TKIs)-namely gefitinib and erlotinib. However, these patients eventually develop resistance to EGFR-TKIs. Despite the fact that this acquired resistance may be the result of a secondary mutation in the EGFR gene, such as T790M or amplification of the MET proto-oncogene, there are other mechanisms which need to be explored. MicroRNAs (miRs) are a class of small non-coding RNAs that play pivotal roles in tumorigenesis, tumor progression and chemo-resistance. In this study, we firstly successfully established a gefitinib resistant cell line-HCC827/GR, by exposing normal HCC827 cells (an NSCLC cell line with a 746E-750A in-frame deletion of EGFR gene) to increasing concentrations of gefitinib. Then, we found that miR-214 was significantly up-regulated in HCC827/GR. We also showed that miR-214 and PTEN were inversely expressed in HCC827/GR. Knockdown of miR-214 altered the expression of PTEN and p-AKT and re-sensitized HCC827/GR to gefitinib. Taken together, miR-214 may regulate the acquired resistance to gefitinib in HCC827 via PTEN/AKT signaling pathway. Suppression of miR-214 may thus reverse the acquired resistance to EGFR-TKIs therapy.

Prediction Model for unfavorable Outcome in Spontaneous Intracerebral Hemorrhage Based on Machine Learning

Shengli Li,Jianan Zhang,Xiaoqun Hou,Yongyi Wang,Tong Li,Zhiming Xu,Feng Chen,Yong Zhou,Weimin Wang,Mingxing Liu 대한신경외과학회 2024 Journal of Korean neurosurgical society Vol.67 No.1

Objective : The spontaneous intracerebral hemorrhage (ICH) remains a significant cause of mortality and morbidity throughout the world. The purpose of this retrospective study is to develop multiple models for predicting ICH outcomes using machine learning (ML). Methods : Between January 2014 and October 2021, we included ICH patients identified by computed tomography or magnetic resonance imaging and treated with surgery. At the 6-month check-up, outcomes were assessed using the modified Rankin Scale. In this study, four ML models, including Support Vector Machine (SVM), Decision Tree C5.0, Artificial Neural Network, Logistic Regression were used to build ICH prediction models. In order to evaluate the reliability and the ML models, we calculated the area under the receiver operating characteristic curve (AUC), specificity, sensitivity, accuracy, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR). Results : We identified 71 patients who had favorable outcomes and 156 who had unfavorable outcomes. The results showed that the SVM model achieved the best comprehensive prediction efficiency. For the SVM model, the AUC, accuracy, specificity, sensitivity, PLR, NLR, and DOR were 0.91, 0.92, 0.92, 0.93, 11.63, 0.076, and 153.03, respectively. For the SVM model, we found the importance value of time to operating room (TOR) was higher significantly than other variables. Conclusion : The analysis of clinical reliability showed that the SVM model achieved the best comprehensive prediction efficiency and the importance value of TOR was higher significantly than other variables.

Closed-form solution of axisymmetric deformation of prestressed Föppl-Hencky membrane under constrained deflecting

Yong-Sheng Lian,Jun-Yi Sun,Jiao Dong,Zhou-Lian Zheng,Zhi-Xin Yang 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.69 No.6

In this study, the problem of axisymmetric deformation of prestressed Föppl-Hencky membrane under constrained deflecting was analytically solved and its closed-form solution was presented. The small-rotation-angle assumption usually adopted in membrane problems was given up, and the initial stress in membrane was taken into account. Consequently, this closed-form solution has higher calculation accuracy and can be applied for a wider range in comparison with the existing approximate solution. The presented numerical examples demonstrate the validity of the closed-form solution, and show the errors of the contact radius, profile and radial stress of membrane in the existing approximate solution brought by the small-rotation-angle assumption. Moreover, the influence of the initial stress on the contact radius is also discussed based on the numerical examples.

Dynamic Characteristics of Saturated Soft Clays under Cyclic Loading in Drained Condition

Yong-hong Miao,Ruo-Yu Sheng,Jie Yin,Fan-Bo Zhou,Jian-fei Lu 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.2

This study presents an experimental investigation on the effects of cyclic loading waveform and cyclic stress ratio (CSR) on dynamic behaviors through laboratory tests on a source of soft clay under cyclic loading in drained condition. Test results showed that under different cyclic loading waveforms at a given frequency (f = 1 Hz) and CSR = 0.6, the axial strain increases significantly at a relatively lower number of cycles (N) and then became stable, while the axial strain consistently decreases with the increasing N and tend to be stable. At a given N, specimen under sine wave cyclic loads shows a higher axial strain rate than that under triangle wave or square cyclic loads. Test results also indicated that at different CSRs, the axial strain increases rapidly at a relatively lower N and then gradually tends to be stable with the increasing N at lower CSR yet there is no stable trend for specimens at higher CSR, which indicates there is a critical value of CSR. It is recommended to apply the cyclic loading in sine waveform with CSR close to and less than the critical value to get a better treatment effect.

Design and testing of CFRP sleeve for a high-speed permanent magnet synchronous motor with surface-mounted rotor

Yong Zhou,Lei Tian,Sheng-Hua Gao,Jing-Wei Zhang,Lin-Ke Yang,Rui-Guang Xie 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.1

A high-speed (HS) permanent magnet (PM) synchronous motor (HSPMSM) with a carbon fiber-reinforced plastic (CFRP) protective sleeve in the surface-mounted rotor was explored in this study. In view of retaining the PMs at HS operations, the high-strength CFRP sleeve was designed on the basis of a process that could be summarized as follows. First, a multi-physics analysis of the rotor was conducted. The requirements to the CFRP sleeve were obtained from electromagnetic analysis, loss analysis, heat flow coupling computational fluid dynamics analysis, structural analysis, and rotor dynamics analysis. Second, the CFRP sleeve was designed by theoretical analysis. From the results, the thickness values of the carbon fibers in the circumferential and helical directions were chosen to be 4 and 1 mm, respectively, while the helical angle of carbon fibers was chosen to be 70°. Then, a plateshaped CFRP product and a cylindrical CFRP product were fabricated to verify the strength and stiffness of the CFRP sleeve. The performance test results show that the hoop strength and elastic modulus and the axial strength and elastic modulus of the plate-shaped CFRP products at 20 °C are 1963 MPa @ 156 GPa and 550 MPa @ 36 GPa, respectively. The hoop strain and axial strain of the cylindrical CFRP product under 35 MPa are about 3000 and 1900 με, which meet the design requirements of the HSPMSM.

Structural and chemical synergistic effect of CoS nanoparticles and porous carbon nanorods for high-performance sodium storage

Zhou, Limin,Zhang, Kai,Sheng, Jinzhi,An, Qinyou,Tao, Zhanliang,Kang, Yong-Mook,Chen, Jun,Mai, Liqiang Elsevier 2017 Nano energy Vol.35 No.-

<P><B>Abstract</B></P> <P>Considering inherent large structural deterioration of conversion-type anode materials during repeated sodiation/desodiation process, the ingenious integration of both nanostructure engineering and chemical hybridization is highly desirable and challenging. Here, ultrafine CoS nanoparticles embedded in porous carbon nanorods (denoted as 7-CoS/C) were facilely fabricated via simultaneous in-situ carbonization and sulfidation of Co-metal organic frameworks (Co-MOF) and have been applied as anode materials for sodium-ion batteries (SIBs). Benefiting from the advantageous embedding architecture between the nanoparticles and porous nanorods, the 7-CoS/C delivers long-term cycling stability (542mAhg<SUP>−1</SUP> after 2000 cycles with a capacity retention of 91.4% at 1Ag<SUP>−1</SUP>) and excellent rate performance (discharge capacities of 510mAhg<SUP>−1</SUP> at 5Ag<SUP>−1</SUP> and 356mAhg<SUP>−1</SUP> even at 40Ag<SUP>−1</SUP>), which is proved to be characterized of partial pseudocapacitive behaviors during the sodiation/desodiation process. In addition, Na<SUB>3</SUB>V<SUB>2</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>/7-CoS/C full cell with excessive amount of Na<SUB>3</SUB>V<SUB>2</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB> has been assembled and exhibits a capacity of 352mAhg<SUP>−1</SUP> at 0.5Ag<SUP>−1</SUP>. This meaningful approach can be extended to build embedded porous structure of other hybrid composites for next-generation energy-storage technology.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The embedded hybrid architecture of the 7-CoS/C is favorable for relieving volume expansion and immobilizing the CoS nanoparticles sites. </LI> <LI> The effect of different electrolyte on the 7-CoS/C/Na system was investigated. </LI> <LI> The variation of structure and valence in Na<SUP>+</SUP> insertion/extraction process of the 7-CoS/C is presented by <I>ex situ</I> XANES. </LI> <LI> The unique structural feature of the 7-CoS/C reveals obvious advantages at more than 1Ag<SUP>−1</SUP> compared with other anode materials. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Prospective UNCITRAL Technical Assistance for Asian Countries in International Arbitration

( Qi Sheng He ),( Da Yong Zhou ) 고려대학교 법학연구원 2011 The Asian Business Lawyer Vol.7 No.-

The United Nations Commission on International Trade Law (UNCITRAL) is a core legal body established by the United Nations, which takes the mandate to harmonize the international and regional trade law, and to create an environmentfacilitating international trade and commercial transactions. In the field of international commercial arbitration, UNCITRAL conducts cooperation programs and provides technical assistance to facilitate its mission. In Asia, facing a rapid regional economic boost but divergent legal systems, improving the professional quality and credibility of regional arbitral institutes shall meet the continual increased regional need for commercial arbitrations and guarantee the accurate application of international law. This article introduces the function of UNCITRAL, gives a brief analysis of the demand for improving international commercial arbitration in Asia, and suggests that UNCITRAL as an appropriateorganization may prospectively contribute to promote the competences of regional arbitral institutes and arbitral participants by means of providing active technical assistance and cooperative projects. Two tentative proposals are put forward in this article from a practical perspective.

Study of the Correlation of Plasma Resonance and the Refractive Index to Dielectric Dispersion in the Complex Plane

Xiao-Yong Zhou,Yan Shen,Er-Tao Hu,Jian-Bo Chen,Yuan Zhao,Ming-Yu Sheng,Jing Li,Yu-Xiang Zheng,Hai-Bin Zhao,Liang-Yao Chen,Wei Li,Xun-Ya Jiang,이영백,David W. Lynch 한국광학회 2013 Current Optics and Photonics Vol.17 No.1

Based on the dispersive feature of the dielectric function of noble metals and the wave vector conservation in physics, both the plasma effect and the complex refractive index, which are profoundly correlated to the complex dielectric function and permeability, have been studied and analyzed. The condition to induce a bulk or a surface plasma in the visible region will not be satisfied, and there will be one solution for the real and the imaginary parts of the refractive index, restricting it only to region I of the complex plane. The results given in this work will aid in understanding the properties of light transmission at the metal/dielectric interface as characterized by the law of refraction in nature.

Soluble Expression of Recombinant Human Smp30 for Detecting Serum Smp30 Antibody Levels in Hepatocellular Carcinoma Patients

Zhang, Sheng-Chang,Huang, Peng,Zhao, Yong-Xiang,Liu, Shu-Yan,He, Shu-Jia,Xie, Xiao-Xun,Luo, Gou-Rong,Zhou, Su-Fang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Senescence marker protein 30 (SMP30), a hepatocellular carcinoma (HCC) associated antigen, was earlier shown by our research group to be highly expressed in HCC paracancerous tissues, but have low levels in HCC tissues. In order to detect anti-SMP30 antibody in serum of HCC patients, we established pET30a-SMP30 and pColdIII-SMP30 expression systems in Escherichia coli. However, the expression product was mainly in the form of inclusion bodies. In this research, we used several combinations of chaperones, four molecular chaperone plasmids with pET30a-SMP30 and five molecular chaperone plasmids with pColdIII-SMP30 to increase the amount of soluble protein. Results showed that co-expression of HIS-SMP30 with pTf16, combined with the addition of osmosis-regulator, and a two-step expression resulted in the highest enhancement of solubility. A total of 175 cases of HCC serum were studied by ELISA to detect anti-SMP30 antibody with recombinant SMP30 protein. Some 22 were positive and x2 two-sided tests all showed P>0.05, although it remained unclear whether there was a relationship between positive cases and clinical diagnostic data.