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101.
采用球囊拉伤动脉内膜加高脂饲养建立兔髂动脉粥样硬化模型.对模型兔进行Nd:YAG激光血管成形术。应用流式细胞计数仪分析细胞中DNA含量。结果表明,治疗组血管平滑肌细胞周期中增殖细胞数明显低于对照组,提示开博通能抑制激光血管成形术后血管平滑肌细胞的增殖。  相似文献   
102.
本文叙述了一种64位声表面波可编程抽头延迟线的结构及性能参数,采用专门设计的有源三极管作开关阵列单元,获得一个时钟速率大于1MHz,可编程速率为15kbit/s的器件。该器件性能基本满足系统实验要求,但在稳定性及波形一致性方面有待进一步提高。  相似文献   
103.
Based on the theory of stochastic differential equation,the stability of a kind ofcontinuous-time generalized Hopfield neural networks with white noise perturbation is studiedin the paper,and the related stability criteria and design requirements of neural networks areestablished.  相似文献   
104.
Distributed multimedia systems   总被引:4,自引:0,他引:4  
A distributed multimedia system (DMS) is an integrated communication, computing, and information system that enables the processing, management, delivery, and presentation of synchronized multimedia information with quality-of-service guarantees. Multimedia information may include discrete media data, such as text, data, and images, and continuous media data, such as video and audio. Such a system enhances human communications by exploiting both visual and aural senses and provides the ultimate flexibility in work and entertainment, allowing one to collaborate with remote participants, view movies on demand, access on-line digital libraries from the desktop, and so forth. In this paper, we present a technical survey of a DMS. We give an overview of distributed multimedia systems, examine the fundamental concept of digital media, identify the applications, and survey the important enabling technologies  相似文献   
105.
双向联想记忆模型是两层异联想网络,本文重点讨论了具有轴突信号传输延迟的双向联想记忆神经网络平衡点存在的条件以及全局稳定性.并用具体例子验证了结论的正确性。本文所讨论的方法具有普遍性,所得到的结果对于网络的设计和应用具有重要的指导意义。  相似文献   
106.
报道了一种新型毫米波天线—衍射天线的测量结果.经分析讨论说明,这种天线具有良好的电性能.  相似文献   
107.
A dose of SBR modifier added to asphalt can improve asphalt's performance in stability, permanence, viscosity, and resistance to aging. Better application performances of asphalt pavement are affected directly by proper SBR modifying. This paper shows some investigations that confirm the relationship between the addition of SBR with the structure and the properties of SBR-modified asphalt. This paper also discusses the modified asphalt high temperature property, low temperature ductility, and mechanism of SBR-modified asphalt. The addition of SBR modifier showed an increase in viscosity, softening point, and elastic recovery of modified asphalt with rising temperature. When the temperature rises, the improvement of SBR-modified asphalt in softening point, elastic recovery, and visco-toughness result from SBR cross-linking. Although the lengths of low temperature ductility of SBR-modified asphalt are increased, the viscosities of modified asphalt increase; however, the softening point between the upper layer and lower layer were about 1.8°C after the isolated experiment.  相似文献   
108.
该文介绍了一种基于微带环缝谐振器的2.45GHz小功率微波等离子体源的建模方法。根据半波长终端开路谐振器的特性,通过选择合适的缝隙宽度和偏转角度、介质基片的介电常数等,使微带环缝谐振器的品质因数最大,同时与馈电端良好匹配。研究表明,实验结果与仿真结果基本吻合,这为小功率微型微波等离子体源的进一步研究提供了理论基础。  相似文献   
109.
Room‐temperature sodium‐ion batteries have attracted great attentions for large‐scale energy storage applications in renewable energy. However, exploring suitable anode materials with high reversible capacity and cyclic stability is still a challenge. The VS4, with parallel quasi‐1D chains structure of V4+(S22?)2, which provides large interchain distance of 5.83 Å and high capacity, has showed great potential for sodium storage. Here, the uniform cuboid‐shaped VS4 nanoparticles are prepared as anode for sodium‐ion batteries by the controllable of graphene oxide (GO)‐template contents. It exhibits superb electrochemical performances of high‐specific charge capacity (≈580 mAh·g?1 at 0.1 A·g?1), long‐cycle‐life (≈98% retain at 0.5 A·g?1 after 300 cycles), and high rates (up to 20 A·g?1). In addition, electrolytes are optimized to understand the sodium storage mechanism. It is thus demonstrated that the findings have great potentials for the applications in high‐performance sodium‐ion batteries.  相似文献   
110.
Combining transition metal oxide catalysts with conductive carbonaceous material is a feasible way to improve the conductivity. However, the electrocatalytic performance is usually not distinctly improved because the interfacial resistance between metal oxides and carbon is still large and thereby hinders the charge transport in catalysis. Herein, the conductive interface between poorly conductive NiO nanoparticles and semi‐conductive carbon nitride (CN) is constructed. The NiO/CN exhibits much‐enhanced oxygen evolution reaction (OER) performance than corresponding NiO and CN in electrolytes of KOH solution and phosphate buffer saline, which is also remarkably superior over NiO/C, commercial RuO2, and mostly reported NiO‐based catalysts. X‐ray photoelectron spectroscopy and extended X‐ray absorption fine structure spectrum reveal that a metallic Ni–N bond is formed between NiO and CN. Density functional theory calculations suggest that NiO and CN linked by a Ni–N bond possess a low Gibbs energy for OER intermediate adsorptions, which not only improves the transfer of charge but also promotes the transmission of mass in OER. The metal–nitrogen bonded conductive and highly active interface pervasively exists between CN and other transition metal oxides including Co3O4, CuO, and Fe2O3, making it promising as an inexpensive catalyst for efficient water splitting.  相似文献   
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