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Crystallographic Analysis of Isothermally Transformed Bainite in 0.2C-2.0Mn-1.5Si-0.6Cr Steel Using EBSD

Journal of Materials Science & Technology 2013年第4期29卷 359-366页

作者： Pasi P.Suikkanen Cyril Cayron Anthony J.DeArdo l.Pentti Karjalainen Ruukki Metals Oy Rautaruukintie 155P.O.Box 93FI-92101 RaaheFinland Department of Mechanical Engineering University of OuluP.O.Box 420090014 University of OuluFinland Ruukki Metals Oy Rautaruukintie 155P.O.Box 93FI-92101 RaaheFinland. CEA LITEN17 rues des Martys38054 GrenobleFrance Department of Mechanical Engineering and Materials Science University of Pittsburgh848 Benedum HallPittsburghPA 15261-2285USA

The crystallography of bainite, transformed isothermally at 450 ℃ in 0.2C-2.0Mn-1.5Si-0.6Cr steel, was investigated by electron backscatter diffraction （EBSD） analysis. The orientation relationship （OR） was found to be closer to Nishiyama-Wassermann （N-W） than Kurdjumov-Sachs orientation relationship. Bainite microstructure consisted of parallel laths forming a morphological packet structure. Typically, there were three different lath orientations in a morphological packet. These orientations were dictated by a three specific N-W OR variants sharing the same {111} austenite plane. A packet of bainite laths with common {111} austenite plane was termed as crystallographic packet. Generally, the crystallographic packet size corresponded to the morphological packet size. locally, crystallographic packets with only two dominant orientations were observed. This indicates strong local variant selection during isothermal bainite transformation. The relative orientation between the variants in crystallographic packets was found to be near 60°/〈110〉. This appears to explain the strong peak observed in the grain boundary misorientation distribution near 60°. Bainite also contained pronounced fraction of boundaries with their misorientation in the range of 2.5°-8° with quite widely dispersed rotation angles. Spatially these boundaries were found to locate inside the bainite laths, forming lath-like sub-grains.

关键词： Bainite Austenite Nishiyama-Wassermann orientation relationship Electron backscatter diffraction OEBSD) Crystallography Packet

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烟酰胺核糖对MPP^(+)诱导SH-SY5Y细胞损伤的保护及机制研究

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中国现代医学杂志 2024年第17期34卷 61-66页

作者：杨艳梅隋易航吕志宇西南医科大学附属医院神经内科四川泸州646000

目的探究烟酰胺核糖(NR)对1-甲基-4-苯基-吡啶离子(MPP^(+))诱导的SH-SY5Y细胞损伤的保护作用及其潜在机制。方法取对数生长期的H-SY5Y细胞来完成实验,使用3 mmol/l MPP^(+)处理细胞构建帕金森病(PD)体外模型。细胞分为对照组(常规培养)... 详细信息

目的探究烟酰胺核糖(NR)对1-甲基-4-苯基-吡啶离子(MPP^(+))诱导的SH-SY5Y细胞损伤的保护作用及其潜在机制。方法取对数生长期的H-SY5Y细胞来完成实验,使用3 mmol/l MPP^(+)处理细胞构建帕金森病(PD)体外模型。细胞分为对照组(常规培养)、MPP^(+)组(MPP^(+)处理)、实验组(0.5 mmol/l NR和MPP^(+)处理)。细胞培养后检测细胞存活率、凋亡率,氧化应激水平[活性氧(ROS)、丙二醛(MDA)、超氧化物歧化酶(SOD)],炎症水平[白细胞介素-6(Il-6)、肿瘤坏死因子-α(TNF-α)],烟酰胺腺嘌呤二核苷酸(NAD^(+))水平等指标。结果与对照组比较,MPP^(+)组细胞凋亡率、ROS、MDA、TNF-α、Il-6水平均升高(Pl-6水平均降低(P<0.05),细胞存活率、SOD、NAD^(+)水平均升高(P<0.05)。结论NR可以减轻MPP^(+)诱导的神经细胞损伤,其机制可能与补充NAD^(+)减轻细胞氧化应激和炎症反应有关。

关键词：帕金森病烟酰胺核糖 NAD^(+) 氧化应激

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恩替卡韦治疗后慢性乙型肝炎低病毒血症患者序贯联合艾米替诺福韦治疗的效果研究

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中国现代医学杂志 2024年第8期34卷 15-20页

作者：向文耀李仕雄吕日英贵港市人民医院感染科广西贵港537100

目的探讨在恩替卡韦(ETV)治疗后出现低病毒血症(llV)的慢性乙型肝炎(CHB)患者,采取序贯联合艾米替诺福韦(TMF)治疗的临床效果。方法选取2021年7月—2023年1月在贵港市人民医院感染科经ETV抗病毒治疗的CHB患者200例。根据治疗期间HBV ... 详细信息

目的探讨在恩替卡韦(ETV)治疗后出现低病毒血症(llV)的慢性乙型肝炎(CHB)患者,采取序贯联合艾米替诺福韦(TMF)治疗的临床效果。方法选取2021年7月—2023年1月在贵港市人民医院感染科经ETV抗病毒治疗的CHB患者200例。根据治疗期间HBV DNA水平,将患者分为完全病毒学应答组(64例)和llV组(136例),分析两组临床资料。根据llV组抗病毒治疗方案,分为3组:续用ETV为对照组(40例)、换用TMF为序贯组(45例)、ETV联合TMF为联合组(51例),持续治疗48周。比较3组治疗48周时HBV DNA转阴率、乙肝表面抗原(HBsAg)、E抗原(HBeAg)、丙氨酸转氨酶(AlT)、天冬氨酸转氨酶(AST)、肌酐(Cr)和肝硬度测定值(lSM)及不良反应发生率。结果完全病毒学应答组HBeAg阳性率、HBV DNA、PlT、lSM、AlT、AST均低于llV组(P lT均低于llV组(P lT、AST均低于对照组(P lT均高于对照组(P lSM低于对照组(P 0.05)。结论序贯或联合TMF治疗能更有效地提高ETV治疗后llV患者完全病毒学应答率,并改善患者肝肾功能,减轻肝纤维化程度。

关键词：慢性乙型肝炎低病毒血症恩替卡韦艾米替诺福韦肝功能

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Comparison of Velocity Shear with Turbulence Reduction Driven by Biasing in a Simple Cylindrical Slab Plasma

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Plasma Science and Technology 2010年第4期12卷 391-396页

作者： K.W.GENTlE K.lIAO K.lEE W.l.ROWAN Institute of Fusion Studies University of Texas at Austin

In an experimental realization of the sheared cylindrical slab, the level of plasma turbulence is strongly reduced by application of a sufficient bias potential difference in the radial direction. Density fluctuation levels △nrms/n decrease by more than a factor of five. The ion flow velocity profile is measured spectroscopically from the Doppler shift of an argon ion line. Comparison of the shearing rates with the turbulent amplitudes as a function of bias show no relation between the shearing rate and turbulence reduction, contrary to expectations.

关键词： turbulence suppression shear stabilization velocity shear bias

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Spermine induced reversible collapse of deoxyribonucleic acid-bridged nanoparticle-based assemblies

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Nano Research 2018年第1期11卷 383-396页

作者： Kristian l. Goeken Richard B. M. Schasfoort Vinod Subramaniam Ron Gill MIRA Institute for Biomedical Technology and Technical Medicine University of Twente Dfienerlolaan 5 7522 NB Enschede the Netherlands Vrije UniversiteitAmsterdam De Boelelaan 1105 1081 HVAmsterdam the Netherlands Saxion University of Applied Sciences M. H. Tromplaan 28 7513 A8 Enschede the Netherlands

DNA-linked 2D and 3D nano-assemblies find use in a diverse set of applications, ranging from DNA-origami in drug delivery and medical imaging, to DNA-linked nanoparticle structures for use in plasmonics and （bio）sensing. However, once these structures have been fully assembled, few options are available to modulate structure geometry. Here, we investigated the use of the polycation spermine to induce DNA collapse in small oligonucleotide-linked （54 bp） gold nanoparticle structures by monitoring shifts in the localized surface plasmon resonance （lSPR） peak and by comparing the data with finite-difference time-domain （FDTD） simulations. Our data shows that low concentrations of spermine can be applied to induce large changes in DNA conformation, leading to a significant reduction in interparticle distance （from - 25 to - 3 nm） and enhanced plasmonic coupling. The DNA collapse is near-instantaneous and reversible, and its application at low and high DNA densities is demonstrated with surface plasmon resonance imaging （SPRi）, showing the potential of spermine to dynamically modulate distances and geometry in DNA-based nano-assemblies.

关键词： nanoparticles spermine deoxyribonucleic acid localized surface plasmonresonance surface plasmon resonanceimaging

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Coumarin-derived azolyl ethanols:synthesis,antimicrobial evaluation and preliminary action mechanism

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Science China Chemistry 2016年第7期59卷 878-894页

作者： Xin-Mei Peng Kannekanti Vijaya Kumar Guri l.V. Damu Cheng-He Zhou Institute of Bioorganic & Medicinal Chemistry Key Laboratory of Applied chemistry of Chongqing MunicipalitySchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

A series of coumarin-derived azolyl ethanols including imidazolyl,triazolyl,tetrazolyl,benzotriazolyl,thiol-imidazolyl and thiol-triazolyl ones were conveniently synthesized and characterized by IR,~1H NMR,^(13)C NMR and high-resolution mass spectra(HRMS) *** of the prepared compounds showed appropriate logP_(ow) values and effective antibacterial and antifungal ***,compound 14 with bis-triazolyl ethanol group exhibited low minimal inhibitory concentration(MIC)value of 8 μg/ml against MRSA,which was comparable or even superior to reference drugs Norfloxacin(MIC=8μg/ml)and Chloramphenicol(MIC=16μg/ml).It could also effectively inhibit the growth of the tested fungal strains compared to *** binding studies of coumarin 14 with calf thymus DNA were investigated by UV-Vis absorption and fluorescence *** was found that compound 14 could interact with calf thymus DNA by groove binding to form14-DNA complex via both hydrogen bonds and van der Waals force,which might be the factor to exert the powerful antimicrobial activity.

关键词： coumarin imidazole triazole tetrazole antibacterial antifungal calf thymus DNA

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NONlINEAR APPROXIMATION WITH GENERAl WAVE PACKETS

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Analysis in Theory and Applications 2005年第3期21卷 201-215页

作者： l.Borup M.Nielsen Aalborg University Aalborg University DenmarkDenmark

We study nonlinear approximation in the Triebel-lizorkin spaces with dictionaries formed by dilating and translating one single function g. A general Jackson inequality is derived for best m-term approximation with such dictionaries. In some special cases where g has a special structure, a complete characterization of the approximation spaces is derived.

关键词： Wavelet tight wavelet frame Besov space Triebel-lizorkin space nonlinear approximation

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An efficient probabilistic design approach for tunnel face stability by inverse reliability analysis

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Geoscience Frontiers 2021年第5期12卷 374-383页

作者： Jian Ji Zheming Zhang Zhijun Wu Jiacheng Xia Yongxin Wu Qing lüc Key laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjingChina School of Civil Engineering Wuhan UniversityWuhanChina c College of Civil EngineeringZhejiang UniversityHangzhouChina

In order to maintain the safety of underground constructions that significantly involve geo-material uncertainties,this paper delivers a new computation framework for conducting reliability-based design(RBD)of shallow tunnel face stability,utilizing a simplified inverse first-order reliability method(FORM).The limit state functions defining tunnel face stability are established for both collapse and blow-out modes of the tunnel face failure,respectively,and the deterministic results of the tunnel face support pressure are obtained through three-dimensional finite element limit analysis(FElA).Because the inverse reliability method can directly capture the design support pressure according to prescribed target reliability index,the computational cost for probabilistic design of tunnel face stability is greatly *** comparison with Monte Carlo simulation results,the accuracy and feasibility of the proposed method are ***,this study presents a series of reliability-based design charts for vividly understanding the limit support pressure on tunnel face in both cohesionless(sandy)soil and cohesive soil stratums,and their optimal support pressure ranges are *** results show that in the case of sandy soil stratum,the blowout failure of tunnel face is extremely unlikely,whereas the collapse is the only possible failure *** parametric study of various geotechnical uncertainties also reveals that ignoring the potential correlation between soil shear strength parameters will lead to over-designed support pressure,and the coefficient of variation of internal friction angle has a greater influence on the tunnel face failure probability than that of the cohesion.

关键词： Tunnel face stability Support pressure Finite element limit analysis Inverse reliability analysis Probabilistic design

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Quality analysis of crustal tilt and strain observations in China's earthquakes in 2014

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Geodesy and Geodynamics 2015年第6期6卷 467-481页

作者： Chen Zhiyao lǖ Pinji Tang lei Institute of Seismology China Earthquake Administration Crusal Movement laboratory Wuhan Base of Institute of Crustal Dynamics China Earthquake Administration Key laboratory of Crustal Dynamics Institute of Crustal DynamicsChina Earthquake Administration

This work analyzes the quality of crustal tilt and strain observations during 2014, which were acquired from 269 sets of ground tiltmeters and 212 sets of strainmeters. In terms of data quality, the water tube tiltmeters presented the highest rate of excellent quality,approximately 91%, and the pendulum tiltmeters and ground strainmeters yielded rates of81% and 78%, respectively. This means that a total of 380 sets of instruments produced high-quality observational data suitable for scientific investigations and analyses.

关键词： Crustal tilt observation Crustal strain observation Observation quality M2tidal wave amplitude factor Mean error in M2tidal wave amplitude Relative mean error in M2tidal wave amplitude Relative noise level Self-calibration internal precision

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The US–China trade war,the American public opinions and its effects on China

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Economic and Political Studies 2019年第2期7卷 169-184页

作者： Edwin l.-C.lai Department of Economics Hong Kong University of Science and Technologythe Hong Kong SARChina

Donald Trump’s trade war with China does not make economic sense,but he does not face much domestic opposition to this trade ***,it is a part of a broader strategy of the nationalistic Americans’attempt to suppress the rise of *** China give in to the requests of the US under the threat of the escalation of the trade war?In what way?My conjecture is that China is willing to compromise up to a *** China is likely to do is to promise to buy more goods and services from the US,allow greater market access for American firms,reduce Chinese subsidies to its industries,reduce forced technology transfers by American firms,strengthen enforcement of intellectual property rights protection and make verification all these commitments more *** the US might stop escalating the trade war,it is likely that the tariffs already imposed on Chinese goods would not be removed *** response to that,China also would not remove most of those tariffs already imposed on imports from the US,in keeping with the spirit of the tit-for-tat *** is possible that a temporary ceasefire is agreed,but the trade war can last for a long *** final assembly stage of many industries might leave China,but not necessarily the whole production *** Kong can be a victim of the trade war if it escalates.

关键词： Trade war American public opinions US–China relations China’s trade balance US–China trade

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