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Electrocardiographic measures of repolarization dispersion and their relationships with echocardiographic indices of ventricular remodeling and premature ventricular beats in hypertension

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journal of Geriatric Cardiology 2017年第12期14卷 717-724页

作者： Ana Ciobanu Gary tse Tong Liu maria V Deaconu Gabriela S Gheorghe Adriana m Iliesiu Ioan T Nanea Department of Internal medicine and Cardiology Theodor Burghele Clinical Hospital Carol Davila University of Medicine and Pharmacy Bucharest Romania Department of medicine and Therapeutics Faculty of Medicine Chinese University of Hong Kong Hong Kong China Li Ka Shing Institute of Health Sci- ences Faculty of Medicine Chinese University of Hong Kong Hong Kong China Tianjin Key Laboratory of Ionic-molecular Function of Cardiovascular disease Department of Cardiology Tianjin Institute of Cardiology Second Hospital of Tianjin Medical University Tianjin China

Objective To examine the relationship between Tpeak- Tend interval （Tpe） and Tpe/QT ratio with occurrence of ventricular premature beats （VPBs） and left ventricular remodeling in hypertension. methods A total of 52 patients with mild to moderate essential hypertension were included, undergoing echocardiography and 24-hours Holter monitoring. Ventricular remodeling was assessed by left ventricular mass index （LVmI） using the Devereux formula and diastolic fimction by transmitral E and A wave velocities and E/A ratio. Tpe was measured in the precordial leads. The end of the T wave was set by the method of the tangent to the steepest descending slope of the T wave. Results Tpe and Tpe/QT in leads V2 （r = 0.33, P = 0.01; r = 0.27, P = 0.04 respectively） and V3 （r = 0.40, P = 0.002; r = 0.40, P = 0.003, respectively） correlated significantly with LVmI. A significant inverse relationship was observed between E/A ratio and QT （r = -0.33, P = 0.01）, Tpe in V3 （r = -0.39, P = 0.003） and Tpe/QT in V3 （r = -0.31, P = 0.02）. Tpe in V3, V5, mean Tpe and maximum Tpe with cut-offvalues of 60 ms, 59 ms, 62 ms and 71 ms, respectively, associated with the occurrence of ventricular premature beats. Conclusions The repolarization parameters Tpe interval and Tpe/QT ratio correlate with LVmI and indices of left ventricular diastolic function and show better predictive values than traditional parameters such as QT interval and QT dispersion. Lead V3 is the best lead for measuring Tpe and Tpe/QT. These ECG indices can therefore be used in clinical practice to monitor LV remodeling and predict occurrence of VPBs.

关键词： Hypertension Repolarization Tpeak-Tend Ventricular remodeling

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INTERACTIONS BETWEEN La_(2)O_(3) PARTICLES AND DISLOCATIONS IN mo-La_(2)O_(3) ALLOyS

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Acta metallurgica Sinica(English Letters) 2005年第6期18卷 714-718页

作者： j.X. Zhang D.m. Liu y. Q. Liu m.L. Zhou T. y. Zuo The Key Laboratory of Advanced Functional materials Ministry of EducationBeijing University of Technology Beijing 100022 China

The mechanical properties of molybdenum wires doped with different contents of La2O3 were investigated systematicaUy and the interaction between La2O3 particles with dislocations in mo- La2O3 wires were observed by SEm and TEm. It is shown that mo-La2O3 wires possess much higher tensile strength than the pure mo. In wires the dislocation motion is strongly hindered by La2O3 particles, which remains up to much higher temperature. moreover, a number of prismatic dislocation loops and hexagonal dislocation network have been formed in annealed mo-La2O3 wires. The higher strength of mo-LazOs than the pure mo is attributed to the La2O3 particles dispersion strengthening and dislocation strengthening.

关键词： molybdenum La2O3 dislocation strengthening

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HIGH-TEmPERATURE OXIDATION OF FGH96 P/m SUPERALLOy

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Acta metallurgica Sinica(English Letters) 2007年第2期20卷 102-110页

作者： F.j. Liu m.C. Zhang j.X. Dong y. W. Zhang School of materials Science and Engineering University of Science and Technology BeijingBeijing 100083 China Central Iron and Steel Research Institute Beijing 100081 China

High temperature oxidation behaviors of FGH96 P/m superaUoy have been studied in air at temperatures ranging from 600 to 1000℃. By means of isothermal oxidation testing, X-ray diffraction, SEm （scanning electron microscopy）, and EDS （energy dispersive X-ray spectroscopy） analyses, the oxidation kinetics as well as the composition and morphology of scales were investigated. Thermodynamic calculations were used to explain the oxidation mechanism. The results showed that as the oxidation temperature increased, the oxidation rate, the scale thickness, and scale spallation increased. FGH96 P/m superalloy exhibits good oxidation resistance at temperature below 800℃. The oxidation kinetics follows an approximately parabolic rate law, and the oxide layer was mainly composed of Cr2O3 TiO2 and a little amount of NiCr2O4. The oxidation is controlled by the transmission of chromium. titanium, and oxygen through the oxide scale.

关键词： FGH96 P/m superalloy high temperature oxidation oxide scale

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Safety estimation of high-pressure hydraulic cylinder using FSI method

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排灌机械工程学报 2016年第5期34卷 418-423页

作者： KIm j.H. HAN S.m. KIm y.j. Graduate School of mechanical Engineering Sungkyunkwan University Suwon 16419 Republic of Korea HKC CO. Ltd. Ansan 425 - 836 Republic of Korea School of mechanical Engineering Sungkyunkwan University Suwon 16419 Republic of Korea

Hydraulic cylinder is a primary component of the hydraulic valve *** numerical study of hydraulic cylinder to evaluate the stress analysis,the life assessment and the performance of operation characteristics in hydraulic cylinder were *** calculation of safety factor,fatigue life,piston chamber pressure,rod chamber pressure and the change of velocity of piston with flow time after the beginning of hydraulic cylinder were *** analysis was performed using the commercial CFD code,ANSyS with unsteady,dynamic mesh model,two-way FSI(fluid-structure interaction)method and k-εturbulent *** internal pressure in hydraulic cylinder through stress analysis show higher than those of the yield strength.

关键词： two-way fluid-structure interaction high-pressure hydraulic cylinder durability life safety estimation dynamic mesh

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Detection of Breaking Waves Using X-Band Pulse Radar in the Nearshore Region

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China Ocean Engineering 2013年第4期27卷 549-556页

作者： y.C.Lin C.C.Chang m.C.Lee H.C.Chan j.m.Leu Department of Hydraulic and Ocean Engineering National Cheng-Kung University Department of Soil and Water Conservation National Chung Hsing University Department of Hospitality management Taiwan Shoufu University

An X-band pulsed Doppler microwave radar has been used to determine the characteristics of breaking waves. Field experiments were conducted at the Shuang-Si estuary in the north of Taiwan in the winter of 2005. Analyses on maxima radar cross section and Doppler frequency shift are done to characterize wave breaking zones. Based on observations of breaking waves, the wave breaking zones are shown to be located at water depths of 1.8 to 2.2 m in the experimental site. In general, the results indicate that a radar system has the potential to delineate the spatial variation of breaking waves clearly and that this is sufficient to achieve a measurement operation for near-shore air-sea interaction events.

关键词： radar Doppler effect wave breaking coastal zone

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Crocodile blood supplementation protect svascular function in diabetic mice

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Food Production, Processing and Nutrition 2021年第1期3卷 283-295页

作者： Chui yiu Bamboo Chook Francis m.Chen Gary tse Fung Ping Leung Wing Tak Wong School of Life Sciences Faculty of ScienceThe Chinese University of Hong KongShatinNTHong Kong SAR State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong KongChina

Cardiovascular disease is a major cause of mortality in diabetic patients due to the heightened oxidative stress and pro-inflammatory state in vascular *** approaches targeting cardiovascular health for diabetic patients are urgently *** blood,an emerging dietary supplement,was suggested to have anti-oxidative and anti-inflammatory effects in vitro,which have yet to be proven in animal *** study thereby aimed to evaluate whether crocodile blood can protect vascular function in diabetic mice against oxidation and *** db/db mice and their counterparts db/m+mice were treated daily with crocodile blood soluble fraction(CBSF)or vehicle via oral gavage for 4 weeks before their aortae were harvested for endothelium-dependent relaxation(EDR)quantification using wire myograph,which is a well-established functional study for vascular function *** culture experiments culturing mouse aortae from C57BL/6 j mice with or without IL-1βand CBSF were done to evaluate the direct effect of CBSF on endothelial *** oxygen species(ROS)levels in mouse aortae were assessed by dihydroethidium(DHE)staining with inflammatory markers in endothelial cells quantified by quantitative polymerase chain reaction(qPCR).CBSF significantly improved deteriorated EDR in db/db diabetic mice through both diet supplementation and direct culture,with suppression of ROS level in mouse *** also maintained EDR and reduced ROS levels in mouse aortae against the presence of pro-inflammatory IL-1β.Under the pro-inflammatory state induced by IL-1β,gene expressions of inflammatory cytokines were downregulated,while the protective transcripts UCP2 and SIRT6 were upregulated in endothelial *** study suggests a novel beneficial effect of crocodile blood on vascular function in diabetic mice and that supplementation of diet with crocodile blood may act as a complementary approach to protect against vascular diseases through anti

关键词： Crocodile blood Diabetes mellitus Vascular endothelial function Anti-oxidative Anti-inflammatory

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STRUCTURE, mAGNETISm AND mAGNETORESISTANCE OF ANNEALED Co/Cu DISCONTINUOUS mULTILAyERS

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Acta metallurgica Sinica(English Letters) 1997年第6期10卷 465-473页

作者： yan, S.S. Lou, j.X. Zhang, L. Zhang, R.Z. Zhang, y.m. Liu, y.H. mei, L.m. Huang, j. Shandong Univ Jinan China

Co/Cu discontinuous multilayers were prepared by rf-sputtering method under high sputtering power and then annealed at various temperatures in a high vacuum. The structural, magnetic and transport properties were strongly influenced by the annealing temperature. The annealed samples obviously became discontinuous multilayers. A maximum magnetoresistance ratio of 5.6% was obtained under a relatively low saturation field of about 400 (10/4π) A/m at the optimum annealing temperature of 450°C. When the annealing temperature was increased, the resistivity decreased, and the coercive force and the saturation field increased. The magnetoresistance ratio also depended on the thickness of Co and Cu layers. The magnetic and transport properties were explained on the basis of the discontinuous multilayered structure.

关键词： Copper magnetic properties multilayers Sputtering Transport properties

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The Effect of Non-equilibrium Condensation on the Drag Coefficient in a Transonic Airfoil Flow

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journal of Thermal Science 2012年第6期21卷 518-524页

作者： I.W.Kim m.m.A.Alam S.j.Lee y.D.Kwon S.B.Kwon School of mechanical Engineering Kyungpook Nat.Uni.1370Sankyuk-dongDaegu 702-701Korea Dept.of Advanced & Control Eng.Saga Uni.japan

In this study, a transonic flow past NACA0012 profile at angle of attack α=0^0 whose aspect ratio AR is 1.0 with non-equilibrium condensation is analyzed by numerical analysis using a TVD scheme and is investigated using an intermittent indraft type supersonic wind tunnel. Transonic flows of 0.78-0.90 in free stream mach number with the variations of the stagnation relative humidity（φ0） are tested. For the same free stream mach number, the increase in φ0 causes decrease in the drag coefficient of profile which is composed of the drag components of form, viscous and wave. In the case of the same moo and To, for more than φ0=30%, despite the irreversibility of process in non-equilibrium condensation, the drag by shock wave decreases considerably with the increase of φ0. On the other hand, it shows that the effect of condensation on the drag coefficients of form and viscous is negligible. As an example, the decreasing rate in the drag coefficient of profile caused by the influence of non-equilibrium condensation for the case of m∞=0.9 and φ0 =50% amounts to 34%. Also, it were turned out that the size of supersonic bubble （that is, the maximum height of supersonic zone） and the deviation of pressure coefficient from the value for m=1 decrease with the increase of φ0 for the same m∞.

关键词： Non-equilibrium condensation Transonic moist air Drag coefficient Pressure coefficient

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Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2) thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： S X Chen m m Chen y Liu D W Cao G j Chen Department of microelectronics Jiangsu UniversityZhenjiang 212013China Department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–macao joint Laboratory for Intelligent micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CmOS)***,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin ***,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented Si substrate has been *** analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain HfO_(2)

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Enhancing strength and ductility in the nugget zone of friction stir welded 7mn steel via tailoring austenitic stability

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journal of materials Science & Technology 2024年第18期185卷 174-185页

作者： y.Q.Wang F.y.Li j.X.Su R.H.Duan Z.A.Luo G.m.Xie State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The martensite often appears in the nugget zone(NZ)of friction stir welding(FSW)7 wt.%mn steel due to low austenite stability,deteriorating ductility and *** this work,a 7 wt.%mn steel was sub-jected to FSW,and preheating was used to tailor the austenitic stability to greatly improve the strength-ductility combination of the *** austenitic deformation behavior and strain hardening mechanism in the NZ were systematically *** microstructure of the as-welded NZ was composed of ultrafine blocky ferrite,austenite,and small amounts of martensite,whereas the as-preheated NZ con-tained ultrafine blocky ferrite and austenite,and the concentration of mn in austenite was increased from 8.4 wt.%to 10.7 wt.%.This enhanced the austenitic stability,resulting in a significant increase in the volume fraction of austenite in the as-preheated NZ from 37.3%to 66.4%.The product of strength and elongation(PSE)in the as-preheated NZ increased dramatically from 42.6 GPa%to 67.1 GPa%,depending on a persistent high strain hardening rate(SHR).multiple strain-hardening mechanisms were *** austenite with enhanced stability can provoke sustained transformation-induced plasticity(TRIP)and twinning-induced plasticity(TWIP)effects,and massive dislocation multiplication occurs during tension,resulting in strong strain hardening.

关键词： Friction stir welding medium mn steel Preheating Transformation-induced plasticity Twinning-induced plasticity

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