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减率性交替性左束支阻滞1例
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作者 薛文福 王广智 《实用心电学杂志》 2000年第1期29-30,共2页
患者男,68岁。临床诊断:风湿性心脏病、二尖瓣狭窄并关闭不全、心房颤动、心力衰竭Ⅲ度。6年前在住院期间静脉注射氨力农50mg后5min出现室速,随之室颤,用200瓦秒电击除颤1次转成窦性心律,心率90次/min。
关键词 左束支阻滞 减率性 交替
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Effect of Altitude and Latitude on Surface Air Temperature across the Qinghai-Tibet Plateau 被引量:8
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作者 WANG Keli SUN Jia +1 位作者 CHENG Guodong JIANG Hao 《Journal of Mountain Science》 SCIE CSCD 2011年第6期808-816,共9页
The correlation between mean surface air temperature and altitude is analyzed in this paper based on the annual and monthly mean surface air temperature data from 106 weather stations over the period 1961-2003 across ... The correlation between mean surface air temperature and altitude is analyzed in this paper based on the annual and monthly mean surface air temperature data from 106 weather stations over the period 1961-2003 across the Qinghai-Tibet Plateau. The results show that temperature variations not only depend on altitude but also latitude, and there is a gradual decrease in temperature with the increasing altitude and latitude. The overall trend for the vertical temperature lapse rate for the whole plateau is approximately linear. Three methods, namely multivariate composite analysis, simple correlation and traditional stepwise regression, were applied to analyze these three correlations. The results assessed with the first method are well matched to those with the latter two methods. The apparent mean annual near-surface lapse rate is -4.8 ℃ /km and the latitudinal effect is -0.87 ℃ /°latitude. In summer, the altitude influences the temperature variations more significantly with a July lapse rate of -4.3℃/km and the effect of latitude is only -0.28℃ /°latitude. In winter, the reverse happens. The temperature decrease is mainly due to the increase in latitude. The mean January lapse rate is -5.0℃/km, while the effect of latitude is -1.51℃ /°latitude. Comparative analysis for pairs of adjacent stations shows that at a small spatial scale the difference in altitude is the dominant factor affecting differences in mean annual near-surface air temperature, aided to some extent bydifferences of latitude. In contrast, the lapse rate in a small area is greater than the overall mean value for the Qinghai-Tibet Plateau (5 to 13℃ /km). An increasing trend has been detected for the surface lapse rate with increases in altitude. The temperature difference has obvious seasonal variations, and the trends for the southern group of stations (south of 33 o latitude) and for the more northerly group are opposite, mainly because of the differences in seasonal variation at low altitudes. For yearly changes, the temperature for high-altitude stations occurs earlier clearly. Temperature datasets at high altitude stations are well-correlated, and those in Nanjing were lagged for 1 year but less for contemporaneous correlations. The slope of linear trendline of temperature change for available years is clearly related to altitude, and the amplitude of temperature variation is enlarged by high altitude. The change effect in near-surface lapse rate at the varying altitude is approximately 1.0℃ /km on the rate of warming over a hundred-year period. 展开更多
关键词 Qinghai-Tibet Plateau Surface airtemperature Vertical lapse rate ALTITUDE LATITUDE
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Car Deceleration Considering Its Own Velocity in Cellular Automata Model 被引量:1
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作者 LI Ke-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期113-116,共4页
In this paper, we propose a new cellular automaton model, which is based on NaSch traffic model. In our method, when a car has a larger velocity, if the gap between the car and its leading car is not enough large, it ... In this paper, we propose a new cellular automaton model, which is based on NaSch traffic model. In our method, when a car has a larger velocity, if the gap between the car and its leading car is not enough large, it will decrease. The aim is that the following car has a buffer space to decrease its velocity at the next time, and then avoid to decelerate too high. The simulation results show that using our model, the ear deceleration is realistic, and is closer to the field measure than that of NaSch model. 展开更多
关键词 cellular automaton traffic flow fundamental diagram
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Inelastic Attenuation of Seismic Wave and Site Response near the Xiaowan Reservoir
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作者 Wu Chengdong Fu Hong Tang Shu'en 《Earthquake Research in China》 2008年第2期137-145,共9页
Based on digital seismograms recorded by 11 stations of the Xiaowan Reservoir-induced Earthquake Monitoring Network from May 21,2005 to September 2006,we calculated the inelastic attenuation near Xiaowan reservoir usi... Based on digital seismograms recorded by 11 stations of the Xiaowan Reservoir-induced Earthquake Monitoring Network from May 21,2005 to September 2006,we calculated the inelastic attenuation near Xiaowan reservoir using Atkinson method.We got the relation of Q value to frequency as Q(f)=225.8 f 0.332.Using the Moya method we got the site response of the 11 stations of Xiaowan Network and source parameters of 43 earthquakes.The source parameters were discussed briefly. 展开更多
关键词 Xiaowan reservoir Inelastic attenuation Site response
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Performance improvement of car body structure in 100% frontal impact
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作者 Men Yongxin Peng Hong +2 位作者 Du Lina Chen Wei Wang Zelong 《Engineering Sciences》 EI 2012年第6期47-50,共4页
During the 100%front impact,all the parts of front car will participate in the course;the crash stiffness of bodywork will also reach the peak.During the crash,rational structure of bodywork can resist the distortion,... During the 100%front impact,all the parts of front car will participate in the course;the crash stiffness of bodywork will also reach the peak.During the crash,rational structure of bodywork can resist the distortion,absorb more energy and get better mode of distortion and low deceleration rate,so as to meet the performance of crash safety.The paper mainly makes optimization analysis based on the problems of front side rails,subframe,firewall,and optimization cases are confirmed which can decrease the intrusion and deceleration rate of the whole car.The structure of bodywork after optimization can meet the performance of crash safety. 展开更多
关键词 100 % frontal impact simulation automotive structure optimization case TEST
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Heart rate variability and its response to thyroxine replacement therapy in patients with hypothyroidism
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作者 邢惠莉 沈迎 +2 位作者 陈寒蓓 王一尘 沈卫峰 《Chinese Medical Journal》 SCIE CAS CSCD 2001年第9期10-12,102,共4页
Objective To analyze heart rate variability (HRV)and its changes with thyroxine treatment in patients with hypothyroidism. Methods HRV was analyzed using 24-hour electrocardiographic recording in 38 patients with hy... Objective To analyze heart rate variability (HRV)and its changes with thyroxine treatment in patients with hypothyroidism. Methods HRV was analyzed using 24-hour electrocardiographic recording in 38 patients with hypothyroidism and 21 normal controls. The changes in HRV were evaluated for the 18 hypothyroid patients after 3 months of thyroxine therapy.Results The time domain measurements of HRV in hypothyroid patients were much lower than those in the control group. As to HRV frequency domain, the high frequency power was significantly higher, but the ratio of low frequency power to frequency power for hypothyroid patients was lower than in the controls. These abnormal changes of HRV measurements in hypothyroid patients were improved after treatment with thyroxine and were associated with recovery of serum concentrations of FT3 and FT4. Conclusions Patients with hypothyroidism often have autonomic neuropathies with a higher level of vagal tone. These abnormalities could be partly improved by thyoxine therapy. 展开更多
关键词 heart rate variability · hypothyroidism · autonomic nerve function
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Decay of Solutions to a Linear Viscous Asymptotic Model for Water Waves 被引量:4
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作者 Olivier GOUBET Guillaume WARNAULT 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第6期841-854,共14页
The authors discuss a linear viscous asymptotic model for water waves and the decay rate of solutions towards the equilibrium.
关键词 Water waves Viscous asymptotic models Nonlocal operators Long-time asymptotics
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Pointwise decaying rate of large perturbation around viscous shock for scalar viscous conservation law 被引量:1
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作者 DENG ShiJin WANG WeiKe 《Science China Mathematics》 SCIE 2013年第4期729-736,共8页
In this paper, we consider the large perturbation around the viscous shock of the scalar conservation law with viscosity in one dimension case. We divide the time region into t ≤T0 and t 〉 To for a fixed constant To... In this paper, we consider the large perturbation around the viscous shock of the scalar conservation law with viscosity in one dimension case. We divide the time region into t ≤T0 and t 〉 To for a fixed constant To when applying energy method. Since To is fixed, the case t ≤ To is easy to deal with and when t 〉 To, from the decaying property of the solution, there is a priori estimate for the solution. Thus we can succeed to control the nonlinear term and get the pointwise estimate for the perturbation by the weighted energy method. 展开更多
关键词 viscous conservation law one dimension shock profile large initial data weighted energy esti- mate pointwise estimate
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GENERAL DECAY RATE ESTIMATES FOR VISCOELASTIC WAVE EQUATION WITH VARIABLE COEFFICIENTS 被引量:3
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作者 CAO Xiaomin YAO Pengfei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第5期836-852,共17页
The authors study decay properties of solutions for a viscoelastic wave equation with variable coefficients and a nonlinear boundary damping by the differential geometric approach.
关键词 Energy decay nonlinear boundary damping Riemannian metric viscoelastic wave equation
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Multifunctional V3S4-nanowire/graphene composites for high performance Li-S batteries 被引量:6
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作者 Tianyu Tang Teng Zhang +7 位作者 Lina Zhao Biao Zhang Wei Li Junjie Xu Tao Li Long Zhang Hailong Qiu Yanglong Hou 《Science China Materials》 SCIE EI CSCD 2020年第10期1910-1919,共10页
Lithium sulfur(Li-S)batteries have been regarded as a promising next-generation energy storage system with high theoretical specific capacity and energy density,but still facing challenges.In order to make Li-S batter... Lithium sulfur(Li-S)batteries have been regarded as a promising next-generation energy storage system with high theoretical specific capacity and energy density,but still facing challenges.In order to make Li-S batteries more competitive,combination of trapping sites and electrocatalytic properties for polysulfides is an effective way to improve the battery performance.In this study,we prepare a type of multifunctional V3S4-nanowire/graphene composites(V3S4-G)by uniformly dispersing V3S4 nanowires on the graphene substrate.This structure contributes to the sufficient exposure of multifunctional V3S4 active sites which can anchor polysulfides and accelerate reaction kinetics.Thus,the Li-S batteries based on the multifunctional V3S4-G sulfur cathode deliver a stable cycling performance and good rate capability.Even at sulfur loading of 3 mg cm^−2,the V3S4-G sulfur cathode possesses a low capacity decay rate of 0.186%per cycle at 0.5 C. 展开更多
关键词 Li-S batteries V3S4-G trapping sites electrocatalytic properties
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