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21.
22.
Based on investigating the spatial distribution of the radiation intensity in molecular bands of nitrogen ions the authors
determined the widths of the layers of positive space charge in mixtures of molecular gases in transverse HF excitation. It
is shown that contrary to predictions of the elementary theory these widths depend relatively weakly on the excitation frequency
and the gas pressure.
Reported at the Second International Scientific and Technical Conference on Quantum Electronics, Minsk, November 23–25, 1998.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 715–718, September–October, 1999. 相似文献
23.
随着集成电路特征尺寸的不断缩小, 互连线在芯片内部占的比重越来越大, 但是互连线仅用于数据传输, 芯片计算能力仍然需要依靠晶体管开关实现. 如何在有限的硬件资源内进一步提高芯片的计算能力, 已经成为当前集成电路设计的核心问题. 本文通过研究金属互连线间电容耦合效应, 采用互连线串扰现象完成逻辑运算的思想, 提出一种基于线计算的全加器设计方案. 该方案首先建立线计算模型, 通过调整反相器阈值和不同干扰线与受扰线之间电容耦合强度匹配技术, 采用相同线计算电路结构实现不同功能的逻辑门电路; 然后, 在逻辑门的基础上实现基于线计算的全加器; 最后, 在TSMC 65nm CMOS工艺下仿真验证. 结果表明, 所设计的线计算电路具有正确逻辑功能, 与传统设计方法相比, 线计算逻辑门具有更低开销, 且线计算电路具有抗逆向工程能力. 相似文献
24.
25.
We propose miniature KrCl and XeBr excimer lamps based on a near-surface capacitive discharge. We show that the devices have high specific energy characteristics (radiation power density of up to 7 mW/cm2), a small emitting volume with a stable position in space, and a narrow radiation band. 相似文献
26.
27.
A simple design for performing rapid temperature jumps within a high‐resolution nuclear magnetic resonance (NMR) setting is presented and exemplified. The design is based on mounting, around a conventional NMR glass tube, an inductive radiofrequency (RF) irradiation coil that is suitably tuned by a resonant circuit and is driven by one of the NMR's console high‐power RF amplifiers. The electric fields generated by this coil's thin metal strips can lead to a fast and efficient heating of the sample, amounting to temperature jumps of ≈ 20 °C in well within a second—particularly in the presence of lossy dielectric media like those provided by physiological buffers. Moreover, when wound around a 4‐mm NMR tube, the resulting device fits a conventional 5‐mm inverse probe and is wholly compatible with the field homogeneities and sensitivities expected for high‐resolution biomolecular NMR conditions. The performance characteristics of this new system were tested using saline solutions, as well as on a lyotropic liquid crystal capable of undergoing nematic → isotropic transitions in the neighborhood of ambient temperature. These settings were then incorporated into the performance of a new kind of single‐scan 2D NMR spectroscopy acquisition, correlating the anisotropic and isotropic patterns elicited by solutes dissolved in such liquid‐crystalline systems, before and after a sudden temperature jump occurring during an intervening mixing period. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
28.
Kaijun Song Yong Fan Yonghong Zhang 《International Journal of Infrared and Millimeter Waves》2007,28(6):473-478
A low-profile millimeter-wave substrate integrated waveguide (SIW) power divider/combiner is presented in this paper. The
simplified model of this compact SIW power dividing/combining structure has been developed. Analysis based on equivalent circuits
gives the design formula for perfect power dividing/combining. In order to verify the validity of the design method, a four-way
SIW power divider/combiner circuit operating at Ka band is designed, fabricated and measured. Good agreement between simulated
and measured results is found for the proposed passive power divider/combiner. Experiments on the four-way passive divider/combiner
back-to-back design demonstrate a minimum overall insertion loss of 1.5 dB at 31.1 GHz, corresponding to a power-combining
efficiency of 84%. The measured 10-dB return loss bandwidth is demonstrated to be 2.2 GHz, and its 0.5-dB bandwidth was 2 GHz. 相似文献
29.
Both high and low frequency relaxation oscillations have been observed in an argon capacitive discharge connected to a peripheral grounded chamber through a slot with dielectric spacers. The oscillations, observed from time-varying optical emission of the main discharge chamber, show, for example, a high frequency (46 kHz) relaxation oscillation at 100 mTorr, with an absorbed power near the peripheral breakdown, and a low frequency (2.7-3.7 Hz) oscillation, at a higher absorbed power. The high frequency oscillation is found to ignite a plasma in the slot, but usually not in the periphery. The high frequency oscillation is interpreted by using an electromagnetic model of the slot impedance, combined with the circuit analysis of the system including a matching network. The model is further developed by using a parallel connection of variable peripheral capacitance to analyse the low frequency oscillation. The results obtained from the model are in agreement with the experimental observations and indicate that a variety of behaviours are dependent on the matching conditions. 相似文献
30.
We propose novel compact multiport power dividers based on one-dimensional photonic crystal omnidirectional reflective waveguides. The proposed power dividers have advantages of wide bandwidth, flexible extended output channel number and compact size. The power dividers are numerical simulations using finite-difference time-domain method. Near-complete transmission and uniform at every branch of output power of multi-port power dividers are observed within wide frequency range. For a 1D PhC 1 × 6 power divider, the six output port achieved nearly 16.5% transmission at each arm from 1545 nm to 1553 nm and the size of 1 × 6 power divider is 14.3 μm × 14.3 μm at 1.55 μm operation wavelength. 相似文献