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51.
在线性近似条件下,量子化了非线性薛定谔方程,用后向传播法数值求解了光孤子相互作用对压缩比的影响。数值结果表明,在碰撞距离附近,压缩比显著增加。 相似文献
52.
本文扼要介绍1995年北京中美工程技术研讨会通信组五位美籍华裔专家关于通信技术新动态的专题报告。一是宽带综合业务数字网的同步数字系列(SDH)和异步转移模式(ATM);二是光纤通信系统的光放大器(OFA)、波分多路(WDM)、光电子集成(OEIC)、色散补偿和新型光纤;三是蜂窝网车载移动通信和全国性个人通信业务(PCS)、时分多址(TDMA)和码分多址(CDMA),四是智能网(IN)体系结构、概念模型和业务管理系统(SMS);五是数字传输网的恢复(FASTAR)、维护(TMP)和供应(TSNOW)三种管理平台,及综合网络管理系统(INMS)。 相似文献
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55.
Longlan Cui Hong Xu Ping He Keiko Sumitomo Yoshinori Yamaguchi Hongchen Gu 《Journal of polymer science. Part A, Polymer chemistry》2007,45(22):5285-5295
A hybrid emulsion polymerization was formulated for synthesizing Fe3O4/polystyrene composite latex. This system, containing binary droplets that are magnetic (Mag)‐droplets with a diameter of 100–200 nm and styrene (St)‐droplets with a diameter of 3–4 μm, was obtained by mixing Mag‐miniemulsion and St‐macroemulsion. With extremely low surfactants concentration (?critical micelle concentration, CMC), the nucleated loci are selectively controlled in the Mag‐droplets, as the result of smaller droplet size and larger surface ratio. Both water‐soluble potassium persulfate (KPS) and oil‐soluble 2,2′‐azobis(2‐isobutyronitrile) was adopted to initiate the polymerization. In the presence of KPS, magnetic polystyrene latices with particles size of 60–200 nm, narrow size distribution, and high magnetite content (86 wt % measured by TGA) were attained successfully. The synthesized magnetic Fe3O4/polystyrene latices assembled into well‐ordered hexagonal structure in the surface of a carbon supported copper grid. The influence of various parameters on various aspects of the as‐synthesized Fe3O4/polystyrene was investigated in detail: type of initiator on composite morphology, feed ratio of Mag‐miniemulsion and St‐macroemulsion on magnetite content, and hydrophobic agent or amount of surfactant on size and size distribution. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5285–5295, 2007 相似文献
56.
基于CAN总线的汽车测试解决方案 总被引:1,自引:0,他引:1
更高功能的汽车设计带动更复杂的汽车电子测试技术的发展。中国的汽车测试界尤其面对着设备的短缺、技术的匮乏等诸多困难。本文针对中国的汽车电子测试业。介绍了一种集成的软硬件同步平台。它基于CAN总线领域中的PXI总线。及国际广泛应用的测试管理TestStand软件。构建成高集成度、可靠性、升级维护方便、开放彻底的测试系统。 相似文献
57.
Qiang Xu Nicolici N. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2005,13(11):1275-1285
Extensive research has been carried out for test planning of core-based system-on-a-chip devices. Most of the prior work assumes that all of the embedded cores are wrapped for test purpose. However, some designs may contain user-defined logic or cores that cannot be wrapped due to area constraints or timing violations. This paper discusses how these unwrapped logic blocks can be tested rapidly by adapting the TestRail architecture, which uses only the test control mechanism and the test instructions available through the IEEE 1500 standard for embedded core test. A new test scheduling algorithm, which facilitates a concurrent test of both unwrapped logic blocks and IEEE 1500-wrapped cores, is proposed, and experiments show that it outperforms a previous approach when the available number of tester channels and/or the number of unwrapped logic blocks are small. 相似文献
58.
A wideband miniature G-shaped coplanar waveguide fed dual-band antenna for a wireless local area network (WLAN) is proposed. The proposed antenna has good radiation pattern and can provide two separate measured impedance bandwidths of 0.55 GHz (about 22.9% centred at 2.42 GHz) and 2.85 GHz (about 50.9% centred at 5.60 GHz), so that it easily covers the required bandwidths for WLAN operation. This design results in a small antenna size of 22 times 18.5 mm with the ground plane regarded as part of the antenna structure. 相似文献
59.
M. Gutowski I. Dabkowska J. Rak S. Xu J.M. Nilles D. Radisic K.H. Bowen Jr 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(3):431-439
The photoelectron spectra (PES) of anions of uracil-glycine and uracil-phenylalanine complexes reveal broad features with
maxima at 1.8 and 2.0 eV. The results of ab initio density functional B3LYP and second order M?ller-Plesset theory calculations indicate that the excess electron occupies a
π* orbital localized on uracil. The excess electron attachment to the complex can induce a barrier-free proton transfer (BFPT)
from the carboxylic group of glycine to the O8 atom of uracil. As a result, the four most stable structures of the anion of
uracil-glycine complex can be characterized as the neutral radical of hydrogenated uracil solvated by the anion of deprotonated
glycine. The similarity between the PES spectra for the uracil complexes with glycine and phenylalanine suggests that the
BFPT is also operative in the case of the latter anionic species. The BFPT to the O8 atom of uracil may be related to the
damage of nucleic acid bases by low energy electrons because the O8 atom is involved in a hydrogen bond with adenine in the
standard Watson-Crick pairing scheme.
Received 6 April 2002 Published online 13 September 2002 相似文献
60.
Z.G. Xiao R.J. HuH.Y. Wu G.M. JinZ.Y. Li L.M. DuanH.W. Wang B.G. ZhangS.F. Wang Z.Y. WeiH.S. Xu Y.T. ZhuS.L. Li F. FuX.H. Yuan Z.Q. Feng 《Physics letters. [Part B]》2006
The inclusive reduced velocity correlation functions of the intermediate mass fragments were measured in the reactions of 36Ar + 112,124Sn at 35 MeV/u. The anti-correlation is observed to be stronger in 36Ar + 124Sn system than that in 36Ar + 112Sn. The difference of the correlation functions between the two reactions is mainly contributed by the particle pairs with high momenta. A three body Coulomb repulsive trajectory model is employed to calculate the emission time scale of the IMFs for the two systems. The time scale is 150 fm/c in 36Ar + 112Sn and 120 fm/c in the 36Ar + 124Sn, respectively. 相似文献