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自律性交接性心动过速伴特宽型完全性右束支传导阻滞
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作者 白国喜 彭俐 卢喜烈 《实用心电学杂志》 2003年第2期114-115,共2页
关键词 自律性交接性心动过速 宽型完全性右束支传导阻滞 心电图 先天性心脏病
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基于格兰杰因果分析的针刺不同效应阶段中枢神经传导通路研究 被引量:6
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作者 孙传铸 白丽君 +4 位作者 牛璇 陈红艳 陈鹏 张明 劳力行 《磁共振成像》 CAS CSCD 2014年第6期423-429,共7页
目的探讨针刺不同效应阶段是否会引发中枢神经信号不同的传导通路。材料与方法采用非重复事件相关的实验设计模式和多元格兰杰因果有效连接度分析方法。结果研究表明针刺即时效应仅引发大脑微弱、稀疏的因果有效连接,包括经丘脑的体感... 目的探讨针刺不同效应阶段是否会引发中枢神经信号不同的传导通路。材料与方法采用非重复事件相关的实验设计模式和多元格兰杰因果有效连接度分析方法。结果研究表明针刺即时效应仅引发大脑微弱、稀疏的因果有效连接,包括经丘脑的体感上行传导通路与由额叶皮层投射到疼痛反应区的自上而下的控制通路。持续性效应阶段,仅在针刺足三里穴后会引发广泛大脑区域的更为紧密的因果连接模式。结论针刺效应可能涉及大脑网络多水平层面信息流的整合与交互。 展开更多
关键词 针刺 时间动态响应 异性中枢神经传导通路 磁共振成像
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导管消融左侧Mahaim房室纤维一例
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作者 楚英杰 刘鹏 王小芳 《中国循证心血管医学杂志》 2009年第4期233-234,共2页
关于左侧Mahaim纤维,国外有极少数报道,而国内未见报道。最近,我们遇到一例患者,电生理检查证实其房室旁路位于心脏左侧,具有递减传导特征,心动过速为逆向型房室折返性心动过速,有效消融靶点AV不融合;现报告如下:
关键词 MAHAIM纤维 房室旁路 逆向型房室折返性心动过速 导管消融 有效消融靶点 电生理检查 传导特
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心脏对程控电刺激的反应形式(续)
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作者 李忠杰 《心电学杂志》 2006年第4期242-244,共3页
关键词 反应 电刺激 程控 心脏 期前刺激 希氏束电图 偶联间期 传导特
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预激综合征P-R间期、P-J间期之相关问题
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作者 何方田 《心电学杂志》 2008年第1期120-122,共3页
一、与预激综合征P—R间期长、短有关的因素 预激综合征的P—R间期大多在0.08-0.11s,但有短至0.06s或长达0.20s者。P—R间期的长短主要取决于下列因素:①房室旁道的性质,即是快旁道还是慢旁道?前者顺传不应期≤0.35s,具有全... 一、与预激综合征P—R间期长、短有关的因素 预激综合征的P—R间期大多在0.08-0.11s,但有短至0.06s或长达0.20s者。P—R间期的长短主要取决于下列因素:①房室旁道的性质,即是快旁道还是慢旁道?前者顺传不应期≤0.35s,具有全或无的传导特点,不出现传导延缓或递减性传导,因而不存在一度或二度Ⅰ型传导阻滞;而后者顺传不应期相当长,可达0.6~1.0s, 展开更多
关键词 预激综合征 房室旁道 传导特 传导阻滞 不应期 20s 慢旁道 35s
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完全消融慢径对房室结双径路快径前传功能的影响
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作者 刘立新 陶新智 +2 位作者 雷长城 郑剑光 朱立光 《广西医科大学学报》 CAS 2000年第2期212-213,共2页
观察房室结慢径完全消融后对快径前传功能的影响 ,并分析可能原因。方法 :2 2例确诊为房室结双径路并伴有折返性心动过速 (AVNRT)的患者行房室结改良术消融慢径 ,分别测量手术前后快径的前传有效不应期 (FPERP)、传导时间 (FPCP)及心动... 观察房室结慢径完全消融后对快径前传功能的影响 ,并分析可能原因。方法 :2 2例确诊为房室结双径路并伴有折返性心动过速 (AVNRT)的患者行房室结改良术消融慢径 ,分别测量手术前后快径的前传有效不应期 (FPERP)、传导时间 (FPCP)及心动过速的周期 (SVTP)。结果 :FPERP由 (2 95± 35 ) m s变为 (2 6 1± 47) ms(P <0 .0 5 ) ;FPCP由 (2 6 1± 6 1) m s变为 (2 30± 45 ) m s(P<0 .0 5 )。Δ FPERP与 SVTP有相关性 (r=- 0 .5 35 3,P<0 .0 5 ) ,ΔFPCP与 SVTP无相关性 (P >0 .0 5 )。结论 :消融慢径可以使快径的电生理特征发生改变 ,前传功能得到改善。 展开更多
关键词 心动过速 房室结 导管消融术 心内电生理 传导特
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A study on the electrical property of HgSe under high pressure 被引量:1
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作者 郝爱民 高春晓 +6 位作者 李明 贺春元 黄晓伟 张东梅 于翠玲 关瑞 邹广田 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期2087-2090,共4页
Using a microcircuit fabricated on a diamond anvil cell, we have measured in-situ conductivity of HgSe under high pressures, and investigated the temperature dependence of conductivity under several different pressure... Using a microcircuit fabricated on a diamond anvil cell, we have measured in-situ conductivity of HgSe under high pressures, and investigated the temperature dependence of conductivity under several different pressures. The result shows that HgSe has a pressure-induced transition sequence from a semimetal to a semiconductor to a metal, similar to that in HgTe. Several discontinuous changes in conductivity are observed at around 1.5, 17, 29 and 49GPa, corresponding to the phase transitions from zinc-blende to cinnabar to rocksalt to orthorhombic to an unknown structure, respectively. In comparison with HgTe, it is speculated that the unknown structure may be a distorted CsCl structure. For the cinnabar-HgSe, the energy gap as a function of pressure is obtained according to the temperature dependence of conductivity. The plot of the temperature dependence of conductivity indicates that the unknown structure of HgSe has an electrical property of a conductor. 展开更多
关键词 in-situ conductivity measurement phase transition high pressure
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The role of electrocardiography in the elaboration of a new paradigm in cardiac resynchronization therapy for patients with nonspecific intraventricular conduction disturbance 被引量:2
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作者 Andras Vereckei Gabor Katona +3 位作者 Zsuzsanna Szelenyi Gabor Szenasi Balint Kozman Istvan Karadi 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第2期118-125,共8页
Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB... Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular (LV) region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance (NICD) pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern. 展开更多
关键词 Cardiac resynchronization therapy ELECTROCARDIOGRAPHY Heart failure
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Spatial interfacial heat transfer and surface characteristics during gravity casting of A356 alloy 被引量:2
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作者 Jia-hua LIN Hai-dong ZHAO Jia-min HUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期43-50,共8页
As one of the key boundary conditions during casting solidification process, the interfacial heat transfer coefficient (IHTC) affects the temperature variation and distribution. Based on the improved nonlinear estimat... As one of the key boundary conditions during casting solidification process, the interfacial heat transfer coefficient (IHTC) affects the temperature variation and distribution. Based on the improved nonlinear estimation method (NEM), thermal measurements near both bottom and lateral metal-mold interfaces throughout A356 gravity casting process were carried out and applied to solving the inverse heat conduction problem (IHCP). Finite element method (FEM) is employed for modeling transient thermal fields implementing a developed NEM interface program to quantify transient IHTCs. It is found that IHTCs at the lateral interface become stable after the volumetric shrinkage of casting while those of the bottom interface reach the steady period once a surface layer has solidified. The stable value of bottom IHTCs is 750 W/(m^2·℃), which is approximately 3 times that at the lateral interface. Further analysis of the interplay between spatial IHTCs and observed surface morphology reveals that spatial heat transfer across casting-mold interfaces is the direct result of different interface evolution during solidification process. 展开更多
关键词 A356 alloy SOLIDIFICATION interfacial heat transfer coefficient inverse heat conduction problem surface characteristics
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Theoretical solution of transient heat conduction problem in one-dimensional double-layer composite medium 被引量:2
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作者 周龙 白敏丽 +1 位作者 吕继组 崔文政 《Journal of Central South University》 SCIE EI CAS 2010年第6期1403-1408,共6页
To make heat conduction equation embody the essence of physical phenomenon under study, dimensionless factors were introduced and the transient heat conduction equation and its boundary conditions were transformed to ... To make heat conduction equation embody the essence of physical phenomenon under study, dimensionless factors were introduced and the transient heat conduction equation and its boundary conditions were transformed to dimensionless forms. Then, a theoretical solution model of transient heat conduction problem in one-dimensional double-layer composite medium was built utilizing the natural eigenfunction expansion method. In order to verify the validity of the model, the results of the above theoretical solution were compared with those of finite element method. The results by the two methods are in a good agreement. The maximum errors by the two methods appear when τ(τ is nondimensional time) equals 0.1 near the boundaries of ζ =1 (ζ is nondimensional space coordinate) and ζ =4. As τ increases, the error decreases gradually, and when τ =5 the results of both solutions have almost no change with the variation of coordinate 4. 展开更多
关键词 composite medium transient heat conduction theoretical solution natural eigenfunction expansion method
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Anomalous Transport Characteristics of High Temperature Superconductors and Josephson Currents
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作者 LIANGFang-Ying LIZuo-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期379-384,共6页
The transport characteristics of high temperature superconductor current and Josephson current is inves-tigated in the framework of the modified time-dependent Ginzburg-Landau model and the Lawrence-Doniach model.We e... The transport characteristics of high temperature superconductor current and Josephson current is inves-tigated in the framework of the modified time-dependent Ginzburg-Landau model and the Lawrence-Doniach model.We evaluated the vortex equation and found that the signs of the high temperature superconductor current and theJosephson current can reverse. Some explicit expressions for different cases are derived, which accord with experimentaldata. 展开更多
关键词 SUPERCONDUCTIVITY JUNCTION Josephson current
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Investigation on Transmission Properties of Terahertz Wave Through Semiconductor Aperture
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作者 HE Xiao-Yong CAO Jun-Cheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期485-488,共4页
The transmission properties of terahertz (THz) wave passing through semiconductor aperture have been investigated. The dispersion relationship for surface plasmon polariton (SPP) at different temperatures has been... The transmission properties of terahertz (THz) wave passing through semiconductor aperture have been investigated. The dispersion relationship for surface plasmon polariton (SPP) at different temperatures has been numerically calculated. The results show that the dispersion relationship increases with the increasing of frequency and the decreasing of temperature, the thickness of slab has to be taken into consideration because of the large skin depth for semiconductor slab. In addition, the propagation constant increases with the increasing of frequency and the decreasing of temperature. 展开更多
关键词 TERAHERTZ surface plasmon propagation constant
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Efficient One-Step Generation of Cluster State with Charge Qubits in Circuit QED
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作者 王艺敏 李承祖 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期190-194,共5页
t We propose theoretical schemes to generate highly entangled cluster state with superconducting qubits in a circuit QED architecture. Charge qubits are located inside a superconducting transmission line, which serves... t We propose theoretical schemes to generate highly entangled cluster state with superconducting qubits in a circuit QED architecture. Charge qubits are located inside a superconducting transmission line, which serves as a quantum data bus. We show that large clusters state can be efficiently generated in just one step with the longrange Ising-like unitary operators. The quantum operations which are generally realized by two coupling mechanisms: either voltage coupling or current coupling, depend only on global geometric features and are insensitive not only to the thermal state of the transmission line but also to certain random operation errors. Thus high-fidelity one-way quantum computation can be achieved. 展开更多
关键词 charge qubit cluster state circuit QED
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Transmission Mechanisms of Monetary Policy in Saudi Arabia: Evidence From SVAR Analysis
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作者 Sayyed Mahdi Ziaei 《Journal of Modern Accounting and Auditing》 2012年第7期990-1012,共23页
In this research, the authors evaluate different channels of the monetary policy transmission mechanisms in Saudi Arabia over the last 15 years with a baseline of structural vector autoregressive (SVAR) models. Cont... In this research, the authors evaluate different channels of the monetary policy transmission mechanisms in Saudi Arabia over the last 15 years with a baseline of structural vector autoregressive (SVAR) models. Contemporaneous coefficient in the structural model indicates that while Saudi Arabia pegs its currency to US dollar, monetary policy instrument reacts positively to unexpected changes in the monetary aggregate. In addition to the traditional interest rate channel, the authors have also found the effects of credit channel. Moreover, variance decomposition results show that past shocks of credit, nominal effective exchange rate (NEER), federal funds rate (FFR) and treasury bill (TB) are found to be important for credit growth in shorter and longer horizons. The exchange rate channel has been less significant in comparison to other channels. 展开更多
关键词 monetary policy TRANSMISSION MECHANISM
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Relationship between space charge and nonlinear characteristics of ZnO varistor 被引量:2
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作者 WANG Qian TU YouPing +1 位作者 DING LiJian JU ZeLi 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第7期1771-1778,共8页
In order to reveal the conduction mechanism of ZnO varistor, the pulsed electroacoustic (PEA) measurement is employed to investigate the space charge distribution characteristics of ZnO varistors under different curre... In order to reveal the conduction mechanism of ZnO varistor, the pulsed electroacoustic (PEA) measurement is employed to investigate the space charge distribution characteristics of ZnO varistors under different current densities in this paper. Experimental results show that the relationship between the space charge and the current density is consistent with the voltage-current characteristics, and can reflect the nonlinear characteristics of ZnO varistor. The space charge increases linearly with the increase of the electric field strength and the current density in the small current region, this reflects the decrease of the surface states of the grain boundary and changes of the Schottky barrier. There exists a transition region between the small current and middle current regions, where the current is composed of the current by the emission of thermally activated electrons and the tunneling current. In the middle current region, the space charge will decrease as the current increases, and will disappear with the depletion layer decreasing to zero. 展开更多
关键词 ZnO varistors pulsed electroacoustic (PEA) measurement space charge double Schottky barrier
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Biochar Effect on Water Evaporation and Hydraulic Conductivity in Sandy Soil 被引量:20
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作者 ZHANG Jun CHEN Qun YOU Changfu 《Pedosphere》 SCIE CAS CSCD 2016年第2期265-272,共8页
Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporat... Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporation in a sandy soil from Hebei Province, China. Biochar had strong absorption ability in the sandy soil. The ratio of water content in the biochar to that in the sandy soil was less than the corresponding ratio of porosity. Because of the different hydraulic properties between the sandy soil and the biochar, the saturated hydraulic conductivity of the sandy soil gradually decreased with the increasing biochar addition. The biochar with larger pore volume and average pore diameter had better water retention. More water was retained in the sandy soil when the biochar was added in a single layer, but not when the biochar was uniformly mixed with soil. Particle size of the added biochar had a significant influence on the hydraulic properties of the mixture of sand and biochar. Grinding the biochar into powder destroyed the pore structure, which simultaneously reduced the water absorption ability and hydraulic conductivity of the biochar. For this reason, adding biochar powder to the sandy soil would not decrease the water evaporation loss of the soil itself. 展开更多
关键词 pore structure pore volume POROSITY soil water retention water holding capacity
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Asymptotic Analysis of Transport Properties and Burning Velocities for Premixed Hydrocarbon Flames
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作者 J.Y.Law H.K.Ma 《Journal of Thermal Science》 SCIE EI CAS CSCD 2001年第2期170-175,共6页
Based on premixed flame, the theoretical model of transport properties with temperature variation was established inside a preheated zone. Lewis number of the deficient-to- stoichiometric hydrocarbon/air mixture has b... Based on premixed flame, the theoretical model of transport properties with temperature variation was established inside a preheated zone. Lewis number of the deficient-to- stoichiometric hydrocarbon/air mixture has been theoretically predicted over a wide range of preheated temperature. These predictions are compared with the experimental data on disport properties that exist in the literature. The response of the burning velocity to flame stretch can be parameterized by the laminar flame speed and Markstein length. Therefore, if the laminar flame speed and Markstein number could be accurately simulated by using an analytic expression of characterized temperature, equivalence ratio, and Lewis number, the results are applicable to the prediction of methane, acetylene, ethylene, ethane, and propane flames. Expanding previous studies on the extinction of premixed flames under the influence of stretch and incomplete reaction, the results were further classified and rescaled. Finally, it could be inferred that parameter Pq, the rescaled extinction Karlovitz number could be used to explain the degree or flame quench. 展开更多
关键词 Lewis number laminar flame speed burning velocity Markstein number Karlovitz number.
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On the ratio of different norms of caloric functions and related eigenfunctions of an integral operator
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作者 DING YuTao 1,2,& ZHANG LiQun 1,2 1 Institute of Mathematics,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,China 2 Hua Loo-Keng Key Laboratory of Mathematics,Chinese Academy of Sciences,Beijing 100190,China 《Science China Mathematics》 SCIE 2012年第8期1597-1612,共16页
We investigate the ratio of L 1 and L 2 norms of the Cauchy problem solutions of heat equations with compact support initial data.The related asymptotic behavior of the eigenvalues and eigenfunctions of certain integr... We investigate the ratio of L 1 and L 2 norms of the Cauchy problem solutions of heat equations with compact support initial data.The related asymptotic behavior of the eigenvalues and eigenfunctions of certain integral operators is obtained. 展开更多
关键词 integral operators EIGENVALUES heat equation
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Light propagation characteristics through the annular coupled-cavity waveguides based on the two-dimensional square-lattice photonic crystal
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作者 冯帅 李予喜 +1 位作者 敖玲 任承 《Optoelectronics Letters》 EI 2011年第2期129-132,共4页
The light propagation characteristics through the annular coupled-resonator cavity waveguides are systematically analyzed by the finite-difference time-domain (FDTD) method. It is found that this kind of waveguide has... The light propagation characteristics through the annular coupled-resonator cavity waveguides are systematically analyzed by the finite-difference time-domain (FDTD) method. It is found that this kind of waveguide has more minbands owing to the increasing of the cavity’s size, compared with the traditional line-typed coupled-resonator waveguide. The group velocity of light propagation can be reduced for a further degree when the adjacent annular cavities are interlaced in the perpendicular direction, and a group velocity about 0.00067c (c is the light speed in vacuum) can be obtained. 展开更多
关键词 Finite difference time domain method Light propagation Light velocity Photonic crystals Resonators WAVEGUIDES
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Facile preparation and high performance of wearable strain sensors based on ionically cross-linked composite hydrogels 被引量:11
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作者 Jiahui Bai Ran Wang +3 位作者 Mingxi Ju Jingxin Zhou Lexin Zhang Tifeng Jiao 《Science China Materials》 SCIE EI CAS CSCD 2021年第4期942-952,共11页
Flexible sensors that can respond to multiple mechanical excitation modes and have high sensitivity are of great significance in the fields of electronic skin and health monitoring.Simulating multiple signal responses... Flexible sensors that can respond to multiple mechanical excitation modes and have high sensitivity are of great significance in the fields of electronic skin and health monitoring.Simulating multiple signal responses to skin such as strain and temperature remains an important challenge.Therefore,new multifunctional ion-crosslinked hydrogels with toughness and conductivity were designed and prepared in this work.A chemical gel with high mechanical strength was prepared by cross-linking acrylamide with N,N’-methylenebisacrylamide and ammonium persulfate.In addition,in order to enhance the conductive properties of the hydrogel,Ca^(2+),Mg^(2+)and Al^(3+)ions were added to the hydrogel during crosslinking.The double-layer network makes this ionic hydrogel show excellent mechanical properties.Moreover,the composite hydrogel containing Ca^(2+)can reach a maximum stretch of 1100%and exhibits ultra-high sensitivity(Sp=10.690 MPa^(-1)).The obtained hydrogels can successfully prepare wearable strain sensors,as well as track and monitor human motion.The present prepared multifunctional hydrogels are expected to be further expanded to intelligent health sensor materials. 展开更多
关键词 HYDROGEL ionic cross-linking strain sensor E-skin
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