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71.
利用脉冲激光入射技术研究100级0.18 μm部分耗尽绝缘体上硅互补金属氧化物半导体反相器链的单粒子瞬态效应, 分析了激光入射器件类型及入射位置对单粒子瞬态脉冲传输特性的影响. 实验结果表明, 单粒子瞬态脉冲在反相器链中的传输与激光入射位置有关, 当激光入射第100级到第2级的n型金属-氧化物-半导体器件, 得到的脉冲宽度从287.4 ps增加到427.5 ps; 当激光入射第99级到第1级的p型金属-氧化物-半导体器件, 得到的脉冲宽度从150.5 ps增加到295.9 ps. 激光入射点靠近输出则得到的瞬态波形窄; 靠近输入则得到的瞬态波形较宽, 单粒子瞬态脉冲随着反相器链的传输而展宽. 入射器件的类型对单粒子瞬态脉冲展宽无影响. 通过理论分析得到, 部分耗尽绝缘体上硅器件浮体效应导致的阈值电压迟滞是反相器链单粒子瞬态脉冲展宽的主要原因. 而示波器观察到的与预期结果幅值相反的正输出脉冲, 是输出节点电容充放电的结果. 相似文献
72.
以外腔式可调谐、窄线宽近红外半导体激光为光源,以一对曲率半径r=1 000mm的宽带高反射率平凹镜(反射率R=99.97%)构成的腔长为650mm的对称高精度光学稳定腔,建立了腔增强吸收光谱系统。详细研究了纯净N2O气体、以及N2O和N2的混合气体在不同浓度和不同气压下、中心波长位于6 561.39cm-1的腔增强吸收光谱、光谱强度和谱线宽度,该腔增强吸收光谱系统的有效吸收光程可达1 460km。获得了光谱线宽与气体压强的关系曲线,导出了波数6 561.39cm-1处N2对N2O的压力展宽系数为(0.114±0.004)cm-1·atm-1。采用该腔增强吸收光谱系统,开展了N2O气体检测研究,建立可用于定量检测的N2O气体腔增强吸收光谱强度与气体浓度关系曲线,获得了2.34×10-7cm-1的检测灵敏度,多次重复测量的相对标准偏差(RSD)为1.73%,在微量N2O气体检测中具有很好的应用前景。 相似文献
73.
O. Nilsson 《Journal of separation science》1979,2(12):720-722
Kaiser's “abt” concept rests on the experimental establishment of a linear relation between band width at half height, b0.5, and capacity ratio, k, according to His column specification quantity, hreal, is dependent on the square of the slope a, obtained from a linear regression analysis based on this relation. It is shown in the present paper that an improvement of the experimental conditions leading to a lower extra-column contribution to band broadening, b, introduces a tendency towards a negative curvature in the plot at low k values. The mean slope increases, and an uncritical linear regression would yield an hreal-value which is higher than before and which would be in the opposite direction to the requirements of a reliable column specification. Generally the linear regression analysis has to be moved to higher k regions in cases of curvature, especially as it is also shown that hreal is an estimation of the traditional HETP value, H∞, that would be obtained when k approaches infinity. This theoretically expected relation is a strong motivation for the use of hreal as a column specification, since the b0.5-value associated with H∞ is expected to be practically independent of b. 相似文献
74.
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76.
The spatial inhomogeneity of pulsed atmospheric pressure discharge in argon is investigated using the electron number density Ne diagnostics procedure applied to asymmetrically broadened Ar I lines. A dedicated fitting procedure is used for describing Ar I 703.0 nm line shape recorded from argon gas discharge and H I (at 486.13 and 656.28 nm) lines recorded from Ar-H2 gas mixture discharge. The results revealed the change in Ne in both axial and radial directions. The additional Ar I lines at 614.5, 710.7, 731.2, and 731.6 nm, recorded from integral spatial radiation, are analysed as well to confirm the results from the plasma column region. The possibility of using AlO (B2∑+–X2∑+) and CN (B2∑+–X2∑+) molecular bands for gas temperature Tg measurements in this type of gas discharge source is demonstrated and Tg used as an input parameter for the Ne diagnostics procedure. For the proper identification of molecular band spectral lines, the Fortrat parabolas are constructed. The results obtained from Ar I 703.0 nm line indicate three different Ne values, with Ne1 ≈ 0.6 × 1016 cm−3, Ne2 ≈ 3.6 × 1016 cm−3, and Ne3 ≈ 19 × 1016 cm−3 measured from the plasma column. These Ne values increase in the cathode and anode region. 相似文献
77.
G.D. Roston M.S. Helmi 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,101(2):201-204
As the ground state potential curve is strongly related to spectral line shapes, the minumum position of the ground state potential is obtained from the experiemental absorption profile k(Δν, T) at high density of the radiating atoms. The temperature dependence of the absorption processes of Hg and Cd lines 253.65 and 326.1 nm, respectively perturbed by inert gases (Xe, Kr, Ar and Ne) had been carefully studied over a wide spectral range. Using the point of the maximum temperature dependence Δνm in each case, we are able to calculate the position of the ground state potential Rm using a simple formula. 相似文献
78.
An analysis is made of the effect of Doppler broadening on gain
without inversion (GWI) from different aspects in a closed
lambda-type three-level system with an incoherent pump. It is shown
that, regardless of the driving field being on resonance or not, for
the counter- or co-propagating of the probe and driving fields (PDF),
GWI does not monotonically decrease or increase with increasing
Doppler width. Except for the case of counter-propagating PDF with
off-resonance driving field, at a suitable Doppler width one can
obtain a gain maximum value much larger than that without Doppler
broadening; especially in the situation of the resonant driving
field, the co-propagating geometry leads to a larger GWI. In
addition, for the counter-propagating geometry, when Doppler width is
larger enough, GWI oscillation occurs, and the oscillation amplitude
and region increase with increasing Doppler width. These conclusions
are very different from that obtained in previous investigation
(Lukin {\it et al}, {\it Laser Phys.} {\bf 6} 436 (1996)). 相似文献
79.
80.