Synthesis of Zirconium Oxides on silicon by Radio - Frequency Magnetron Sputtering Deposition

Chunyu Ma,Qingyu Zhang 한국진공학회(ASCT) 2003 Applied Science and Convergence Technology Vol.12 No.S1

Zirconium oxide films have been synthesized by radio-frequency magnetron sputtering deposition on n-Si(001) substrate with metal zirconium target at variant O₂ partial pressures. The influences of O₂ partial pressures of the morphology, deposition rate, microstructure, and the dielectric constant of ZrO₂ have been discussed. The results show that deposition rate of ZrO₂ films decreases, the roughness, and the thickness of the native SiO₂ interlayer increases with the increase of O₂ partial pressure. ZrO₂ films synthesized at low O₂ partial pressure are amorphous and monoclinic polycrystalline in nanometer scale at low O₂ partial pressure. The relative dielectrics of ZrO₂ films are in the range of 12 to 25.

Synthesis of Zirconium Oxides on silicon by Radio-Frequency Magnetron Sputtering Deposition

Ma, Chunyu,Zhang, Qingyu The Korean Vacuum Society 2003 Applied Science and Convergence Technology Vol.12 No.1

Zirconium oxide films have been synthesized by radio-frequency magnetron sputtering deposition on n-Si(001) substrate with metal zirconium target at variant $O_2$ partial pressures. The influences of $O_2$ partial pressures of the morphology, deposition rate, microstructure, and the dielectric constant of $ZrO_2$ have been discussed. The results show that deposition rate of $ZrO_2$ films decreases, the roughness, and the thickness of the native $SiO_2$ interlayer increases with the increase of $O_2$ partial pressure. $ZrO_2$ films synthesized at low $O_2$ partial pressure are amorphous and monoclinic polycrystalline in nanometer scale at low $O_2$ partial pressure. The relative dielectrics of $ZrO_2$ films are in the range of 12 to 25.

어슐러 K. 르 귄의 『환영의 도시』에서의 이중서사구조와 도가적 영향 연구

마춘옥(Chunyu Ma) 한국동서비교문학학회 2020 동서 비교문학저널 Vol.0 No.54

This paper aims at examining the dual narrative structure and the influence of Taoism in Ursula K. Le Guin’s science fiction, City of Illusions (1967). Walter Benjamin, in “The Storyteller: Reflections on the Works of Nikolai Leskov,” classified the evolution of narratives into three different stages: the age of traditional stories, of novels, and of information. And he warned the danger of declining of storytelling at the age of information. Le Guin has shared a similar concern and attempted to restore stories in her novels. This paper consists of five parts. The first is devoted to profile Benjamin’s concern on the problem of the death of stories in the age of information. The second is a comparative analysis of two different forms of narratives, information in Shing’s city and stories in the exiles’ forest in City of Illusions. Through the comparison, the problem of informational narrative has been investigated in the story of a two-minded man. The third part discusses the different features between time of stories and of novels in order to illustrate the influence of Taoism on this novel. The fourth part explores the features of Taoist science fiction by discussing Le Guin’s strategy of interweaving stories and information in the form of science fiction.

Dexmedetomidine inhibits vasoconstriction via activation of endothelial nitric oxide synthase

Nong, Lidan,Ma, Jue,Zhang, Guangyan,Deng, Chunyu,Mao, Songsong,Li, Haifeng,Cui, Jianxiu The Korean Society of Pharmacology 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.5

Despite the complex vascular effects of dexmedetomidine (DEX), its actions on human pulmonary resistance arteries remain unknown. The present study tested the hypothesis that DEX inhibits vascular tension in human pulmonary arteries through the endothelial nitric oxide synthase (eNOS) mediated production of nitric oxide (NO). Pulmonary artery segments were obtained from 62 patients who underwent lung resection. The direct effects of DEX on human pulmonary artery tension and changes in vascular tension were determined by isometric force measurements recorded on a myograph. Arterial contractions caused by increasing concentrations of serotonin with DEX in the presence or absence of L-NAME (endothelial nitric oxide synthase inhibitor), yohimbine (${\alpha}_2$-adrenoceptor antagonist) and indomethacin (cyclooxygenase inhibitor) as antagonists were also measured. DEX had no effect on endothelium-intact pulmonary arteries, whereas at concentrations of $10^{-8}{\sim}10^{-6}mol/L$, it elicited contractions in endothelium-denuded pulmonary arteries. DEX (0.3, 1, or $3{\times}10^{-9}mmol/L$) inhibited serotonin-induced contraction in arteries with intact endothelium in a dose-dependent manner. L-NAME and yohimbine abolished DEX-induced inhibition, whereas indomethacin had no effect. No inhibitory effect was observed in endothelium-denuded pulmonary arteries. DEX-induced inhibition of vasoconstriction in human pulmonary arteries is mediated by NO production induced by the activation of endothelial ${\alpha}_2$-adrenoceptor and nitric oxide synthase.

Study on the dynamic interaction of multiple clearance joints for flap actuation system with a modified contact force model

Qi Wan,Geng Liu,Chunyu Song,Yong Zhou,Shangjun Ma,Ruiting Tong 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.7

To analyze the effects of clearance joint number and dynamic interaction on responses of the flap actuation system, a dynamic analysis model is proposed based on a modified contact force model. The modified contact force model can take contact properties with small clearance, heavy load, large contact area and variable contact stiffness coefficient into consideration for the flap actuation system. Numerical results show that the actuation system presents violent fluctuation due to the dynamic interaction between multiple clearance joints, and the clearance joint closest to the input part suffers more serious contact effects. Furthermore, the combination motion modes between the multiple clearance joints are helpful to judge and analyze the motion state and dynamic behaviors of actuation systems. These simulation findings can provide a theoretical foundation for the optimization design, control strategy and engineering experiments of the actuation systems with multiple clearances.

Structural and functional comparative mapping between the Brassica A genomes in allotetraploid Brassica napus and diploid Brassica rapa.

Jiang, Congcong,Ramchiary, Nirala,Ma, Yongbiao,Jin, Mina,Feng, Ji,Li, Ruiyuan,Wang, Hao,Long, Yan,Choi, Su Ryun,Zhang, Chunyu,Cowling, Wallace A,Park, Beom Seok,Lim, Yong Pyo,Meng, Jinling Springer 2011 TAG. Theoretical and applied genetics. Theoretisch Vol.123 No.6

<P>Brassica napus (AACC genome) is an important oilseed crop that was formed by the fusion of the diploids B. rapa (AA) and B. oleracea (CC). The complete genomic sequence of the Brassica A genome will be available soon from the B. rapa genome sequencing project, but it is not clear how informative the A genome sequence in B. rapa (A(r)) will be for predicting the structure and function of the A subgenome in the allotetraploid Brassica species B. napus (A(n)). In this paper, we report the results of structural and functional comparative mapping between the A subgenomes of B. napus and B. rapa based on genetic maps that were anchored with bacterial artificial chromosomes (BACs)-sequence of B. rapa. We identified segmental conservation that represented by syntenic blocks in over one third of the A genome; meanwhile, comparative mapping of quantitative trait loci for seed quality traits identified a dozen homologous regions with conserved function in the A genome of the two species. However, several genomic rearrangement events, such as inversions, intra- and inter-chromosomal translocations, were also observed, covering totally at least 5% of the A genome, between allotetraploid B. napus and diploid B. rapa. Based on these results, the A genomes of B. rapa and B. napus are mostly functionally conserved, but caution will be necessary in applying the full sequence data from B. rapa to the B. napus as a result of genomic rearrangements in the A genome between the two species.</P>

Dexmedetomidine inhibits vasoconstriction via activation of endothelial nitric oxide synthase

Lidan Nong,Jue Ma,Guangyan Zhang,Chunyu Deng,Songsong Mao,Haifeng Li,Jianxiu Cui 대한생리학회-대한약리학회 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.5

Despite the complex vascular effects of dexmedetomidine (DEX), its actions on human pulmonary resistance arteries remain unknown. The present study tested the hypothesis that DEX inhibits vascular tension in human pulmonary arteries through the endothelial nitric oxide synthase (eNOS) mediated production of nitric oxide (NO). Pulmonary artery segments were obtained from 62 patients who underwent lung resection. The direct effects of DEX on human pulmonary artery tension and changes in vascular tension were determined by isometric force measurements recorded on a myograph. Arterial contractions caused by increasing concentrations of serotonin with DEX in the presence or absence of L-NAME (endothelial nitric oxide synthase inhibitor), yohimbine (α₂-adrenoceptor antagonist) and indomethacin (cyclooxygenase inhibitor) as antagonists were also measured. DEX had no effect on endothelium-intact pulmonary arteries, whereas at concentrations of 10^–8~10^–6 mol/L, it elicited contractions in endothelium-denuded pulmonary arteries. DEX (0.3, 1, or 3×10^–9 mmol/L) inhibited serotonin-induced contraction in arteries with intact endothelium in a dose-dependent manner. L-NAME and yohimbine abolished DEX-induced inhibition, whereas indomethacin had no effect. No inhibitory effect was observed in endothelium-denuded pulmonary arteries. DEX-induced inhibition of vasoconstriction in human pulmonary arteries is mediated by NO production induced by the activation of endothelial α₂- adrenoceptor and nitric oxide synthase.

Dynamic analysis of three-dimensional helical geared rotor system with geometric eccentricity

Yimin Zhang,Qibin Wang,Hui Ma,Jing Huang,Chunyu Zhao 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.11

A dynamic model of a multi-shaft helical geared rotor system is presented. Rotating shafts of the system are modeled as Timoshenko beams. A general three-dimensional dynamic model of helical gear pairs with geometric eccentricity is developed for the gear mesh and bearing flexibility is included in the model as well. The transmission error and gear geometric eccentricity are simulated as excitations. Eigenvalue solution and the modal summation technique are used to predict the natural frequencies and forced responses of the system. Then two geared rotor system models are presented for validation of the gear dynamic model. It is demonstrated that the gear mesh model is effective for general geared rotor systems, spur and helical gears, one-stage and multi-stage systems. Finally, forced responses of an example system are analyzed to demonstrate the influences of the helical gear geometric eccentricity and the coupling between gear geometric eccentricity and rotor mass unbalance.

Biological characterization of mesenchymal stem cells from bovine umbilical cord

Hui Xiong,Wei Jun Guan,Yue Hui Ma,Chunyu Bai,Shuang Wu,Yuhua Gao,Taofeng Lu,Qingyun Hu 한국통합생물학회 2014 Animal cells and systems Vol.18 No.1

Mesenchymal stem cells (MSCs) are multi-potential cells that are able to proliferate and differentiate into othercell types. Much research has been done on the MSCs from the umbilical cord (UCMSCs) in human, mice, andavian, but little literature has been published about these cells in big livestock. Here, we choose Luxi cattle asthe experimental animal, we describe an external culture of the UCMSCs from it and summarize the biologicalcharacteristics of these cells, e.g., morphologic appearance, surface antigens, colony-forming ability, geneexpression, and differentiation potential were detected via using immunofluorescence and reverse transcriptionpolymerase chain reaction (RT-PCR). The induced cells, osteoblast, lipoblast, hepatocyte, islet cells, andneurocyte were identified by Alizarin red staining, Oil-red-O staining, Periodic acid-schiff staining, andDithizone staining and RT-PCR detection for specific genes. Results suggest that biological characteristics ofthe UCMSCs were similar to those of MSCs previously analyzed. The primary UCMSCs were sub-cultured topassage 32, the UCMSCs expressed gene CD29, CD44, CD73, CD90, and CD166, induced cells illustratedtypical staining, and expressed specific genes, which indicate that the UCMSCs could be a novel alternativesource of MSCs for experimental and clinical applications.

The bifunctional effect of propofol on thromboxane agonist (U46619)-induced vasoconstriction in isolated human pulmonary artery

Ning Hao,Zhaojun Wang,Sujuan Kuang,Guangyan Zhang,Chunyu Deng,Jue Ma,Jianxiu Cui 대한생리학회-대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.13 No.3

Propofol is known to cause vasorelaxation of several systemic vascular beds. However, its effect on the pulmonary vasculature remains controversial. In the present study, we investigated the effects of propofol on human pulmonary arteries obtained from patients who had undergone surgery. Arterial rings were mounted in a Multi-Myograph system for measurement of isometric forces. U46619 was used to induce sustained contraction of the intrapulmonary arteries, and propofol was then applied (in increments from 10-300 μM). Arteries denuded of endothelium, preincubated or not with indomethacin, were used to investigate the effects of propofol on isolated arteries. Propofol exhibited a bifunctional effect on isolated human pulmonary arteries contracted by U46619, evoking constriction at low concentrations (10-100 μM) followed by secondary relaxation (at 100-300 μM). The extent of constriction induced by propofol was higher in an endothelium-denuded group than in an endothelium-intact group. Preincubation with indomethacin abolished constriction and potentiated relaxation. The maximal relaxation was greater in the endothelium-intact than the endothelium-denuded group. Propofol also suppressed CaCl₂-induced constriction in the 60 mM K⁺-containing Ca²⁺-free solution in a dose-dependent manner. Fluorescent imaging of Ca²⁺ using fluo-4 showed that a 10 min incubation with propofol (10-300 μM) inhibited the Ca²⁺ influx into human pulmonary arterial smooth muscle cells induced by a 60 mM K⁺-containing Ca²⁺-free solution. In conclusion, propofol-induced arterial constriction appears to involve prostaglandin production by cyclooxygenase in pulmonary artery smooth muscle cells and the relaxation depends in part on endothelial function, principally on the inhibition of calcium influx through L-type voltage-operated calcium channels.