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901.
1 IntroductionFOr LiNbO3 modulators, the bandwidth is mainly restricted by the microwaveattenuation of the travelling--wave electrode and the phase velocity ndsmatch betWeenmicrowave and optical wave in the devices. When the phase velocity matching issatisfied it is very i~rtant to decrease the microwave attenuation for expandingbandwidth. The thecrowave propagating lOSS is the main source Of the microwaveattenuation in the interactive region. The larger the cross-sectional area or the lOn… 相似文献
902.
903.
基于Linux平台的电话语音邮件系统 总被引:1,自引:0,他引:1
通过CTI(电脑语音)技术将电话语音与电子邮件相结合,提出并实现了一个基于Linux平台的电话语音邮件系统,并对原理和各功能模块的实现方法进行了论述。该系统通过Internet和现今十分普及的电信网相连接,提供了一个全方位的交叉的通信平台,拓宽了E-mail的应用领域。 相似文献
904.
胡钧 何建军 # 许世伟 陈志强 张雪荧 王建松 于祥庆 苏俊 李二涛 王宏伟 田文栋 李龙 张立勇 杨彦云 马朋 章学恒 胡正国 郭忠言 徐星 袁小华 鲁皖 余玉洪 臧永东 唐述文 叶瑞平 陈金达 金仕纶 杜成名 王世陶 马军兵 刘龙祥 白真 雷祥国 孙志宇 李湘庆 张玉虎 周小红 徐瑚珊 《原子核物理评论》2011,28(4):428-432
实验通过17F+p共振弹性散射研究了复合核18Ne激发态中与天体核反应14O(α, p)17F相关的共振态性质。利用兰州放射性束流线(RIBLL)对弹核碎裂反应产生的放射性束17F进行了分离和提纯。经过降能后,能量为4.22 AMeV 的17F束流轰击在T2终端的厚氢靶(CH2)n上。 两套∆E-E Si探测器望远镜放置在两个不同的探测角度θlab≈2.3°和14°上,对反冲质子的角度和能量进行了测量。实验观测到了复合核18Ne的几条质子共振能级。通过R-Matrix理论程序对激发函数进行拟合,得到了共振态的能量、 自旋、 宇称和衰变宽度等共振参数。Resonant properties in18Ne relevant to the stellar reaction of 14O(α, p)17F have been investigated through a resonant elastic scattering of 17F+p. The 17F RI beam was produced via a projectile fragmentation reaction, and subsequently separated and purified by Radioactive Ion beam Line in Lanzhou(RIBLL). After a series of energy degradation,a 4.22 AMeV 17F beam bombarded a thick(CH2)ntarget at T2 terminal. Energy and angle of the recoiled protons were measured by two sets of ∆E-E silicon telescope at θlab≈2.3°,14° respectively. Several resonances in 18Ne were observed,and their resonant parametersincluding energy,spin parity and decay width have been determined by an R-Matrix analysis of the experimental excitation function. 相似文献
905.
906.
建立近红外光谱定性分析模型,用于酒石酸美托洛尔片厂家的快速鉴别。采用Antaris Ⅱ傅里叶变换近红外光谱仪和Micro NIR1700型微型近红外光谱仪两种仪器对来自四个生产厂家的66个批次的酒石酸美托洛尔片进行近红外光谱的采集,选用随机(random sampling,RS)法进行样品集的划分,得到校正集样品44个、验证集样品22个,选择一阶导数Savitzky-Golay15(SG15)点平滑、标准正态变量变换(SNV)作为预处理方法,根据不同类样本间光谱的差异结合谱带特征吸收的方法分别选择6 468~7 104和6 468~7 156 cm-1作为建模光谱区间,建立两种采样仪器的偏最小二乘判别分析(PLS-DA)模型。模型的混淆矩阵结果显示两种仪器采集的近红外光谱建立的定性分析模型能够快速、有效的鉴别不同厂家的酒石酸美托洛尔片,模型的准确率和否定率均达到100%。该研究有效证实了近红外光谱分析技术用于酒石酸美托洛尔片厂家定性鉴别的可行性,另外,该研究中采用了目前商业化最小、便于携带的Micro NIR1700型微型光谱仪,为药品的快速现场筛查提供了很好的启示。 相似文献
907.
908.
With NiMnCo and FeCoNi alloys as solvent metals, large single-crystal diamonds of about 3mm across are grown by temperature gradient method (TGM) under high temperature and high pressure (HPHT). Although both {100} and {111} surfaces are developed by a layer growth mechanism, some different characteristic patterns are seen clearly on the different surfaces, no matter whether NiMnCo or FeCoNi alloys are taken as the solvent metals. For {100} surface, it seems to have been melted or etched greatly, no dendritic patterns to be found, and only a large number of growth hillocks are dispersed net-likely; while for {111} surface, it often seems to be more smooth-faced, no etched or melted traces are present even when a lot of depressed trigonal growth layers. This distinct difference between {111} and {100} surfaces is considered to be related to the difference of surface-atom distribution of different surfaces, and {111} surfaces should be more difficult to be etched and more steady than {100} surfaces. 相似文献
909.
910.
Kun Liang Qiong Song Fei Lu Boyu Wu Wang Chen Haibo Peng Chen Liu Shuyun Luo 《Fiber and Integrated Optics》2005,24(6):521-528
Electro-optic (EO) polymer modulators are very promising in the realization of cost-effective and high-performance optical transmissions. In this article, general strategies and specific designs of the traveling wave electrodes in EO polymer modulators were presented to reduce the modulator drive power while maintaining a broadband response. The optimum device parameters and corresponding conditions were estimated using finite element method based on electrode design. In calculating the results, the comprehensive characteristics of polymer modulator with 1.21 V half-wave voltage and 91 GHz bandwidth was demonstrated with electro-optic interaction length is 20 mm, electro-optic coefficient is 55 pm/V, and operation wavelength is 1.319 μm. These results agree with the 0.8 V half-wave voltage and 30 mm electro-optic interaction length reported in Science. In the five designs presented, a hybrid electrode structure combining CPW and microstrip lines were advanced. The characteristics of this structure are like that of microstrip lines with a single-arm electrode on one arm of the waveguide, but it solves the problem of microstrip to coaxial line transition and corona polarization. 相似文献