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961.
Chris E. Hendriks Patrick J. Smith Jolke Perelaer Antje M. J. van den Berg Ulrich S. Schubert 《Advanced functional materials》2008,18(7):1031-1038
Hot‐embossed features are prepared by pushing customized and standard silicon calibration gratings, known as masters, into either polystyrene or polycarbonate, which are kept above their glass transition temperatures. droplet of a silver nanoparticle ink is then dispensed over one of these as‐formed grooves using an inkjet printer. The ink fills the grooves as a consequence of capillary forces and is observed to form tracks with a uniform width. The tracks are described as ‘invisible’ on account of having widths ranging from 5 to 15 µm. Wider tracks can be produced by dispensing more droplets and tracks with different morphologies can be produced by using different masters. Several as‐prepared features are thermally treated to produce conductive silver tracks. The conductivity of the tracks is found to be ~20% that of bulk silver. 相似文献
962.
963.
研究了DC应力n.MOSFET热载流子退化的Sfγ噪声参量.提出了用噪声参数和Sfγ表征高、中、低三种栅应力下n-MOSFET抗热载流子损伤能力的方法.进行了高、中、低三种栅压DC应力下热载流子退化实验.实验结果和本文模型符合较好. 相似文献
964.
S. Bashir 《Applied Surface Science》2009,255(20):8372-8376
By combining new studies of the surface topography and the emission characteristics of particles during interaction of ultra-short-laser radiation with surfaces, in particular during laser ablation, three different types of general processes (sub 100 fs electronic processes like Coulomb explosion (CE) or field ion emission by surface optical rectification (SOR), processes related to electronic plasma (FEP) formation (typically a few hundred fs time scale) and thermal ablation (TA)) could be identified to explain ultra-short-laser ablation of matter at laser intensities around the ablation threshold. In particular, the identification of the unique appearance of individual, localized nano-hillocks, typically a few nm in height and with a diameter below typically 50 nm, can be regarded as characteristic for a strong localized potential energy deposition to the electronic system resulting in CE or SOR. The observation and possibility of CE even on metals has implications beyond the field of laser ablation. A remarkable result observed concerns the similarities between laser ablation and sputtering with highly charged ions. 相似文献
965.
Radiation hardened CC4007RH and non-radiation hardened CC4011 devices were irradiated using ^60Co gamma rays, 1 MeV electrons and 1-9 MeV protons to compare the ionizing radiation damage of the gamma rays with the charged particles. For all devices examined, with experimental uncertainty, the radiation induced threshold voltage shifts (△Vth) generated by ^60Co gamma rays are equal to that of 1 MeV electron and 1-7 MeV proton radiation under 0 gate bias condition. Under 5 V gate bias condition, the distinction of threshold voltage shifts (△Vth) generated by ^60Co gamma rays and 1 MeV electrons irradiation are not large, and the radiation damage for protons energy the proton has, the less serious below 9 MeV is always less than the radiation damage becomes. that of ^60Co gamma rays. The lower 相似文献
966.
Kristen D. Alexander Meredith J. Hampton Shunping Zhang Anuj Dhawan Hongxing Xu Rene Lopez 《Journal of Raman spectroscopy : JRS》2009,40(12):2171-2175
We present a high‐throughput method for fabricating large arrays of surface‐enhanced Raman scattering (SERS) active gold dimers. Using a large‐area/low‐cost nanopatterning method in conjunction with a meniscus force deposition technique, we were able to create large arrays of uniformly spaced nanoclusters comprising two 60‐nm gold nanospheres. Raman measurements of a thiophenol monolayer deposited on smaller scale arrays of aligned dimers yielded enhancement factors as high as 109. Polarization‐controlled measurements show spectral peak heights to be 10–100 times smaller when the incident beam is polarized perpendicularly to the dimer axis, confirming that the measured enhancements arise from the ‘hot spots’ between the two nanospheres. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
967.
以包钢6号高炉、邯钢7号高炉和莱钢1号高炉在线采集的铁水含硅量([Si])的时间序列为样本, 利用多分辨分析剔除样本的长期趋势,对样本保留的波动趋势进行多重分形特征辨识. 通过计算广义Hurst指数、尺度函数、多重分形谱, 全面、细致量化了序列的局部及不同层次的波动奇异性. 计算结果表明: 去除长期趋势后, 三座高炉[Si]序列的波动呈现显著多重分形特征, 这样的波动过程仅用单一的Hurst指数或box维数来描述是不够的.
关键词:
多分辨分析
铁水含硅量
波动
多重分形 相似文献
968.
中高能电子电离He原子的二重微分截面 总被引:1,自引:1,他引:0
这篇文章用BBK和DS3C模型,计算了入射能为100,200,300,400和600 eV等中、高能情况下,电子入射电离He原子的二重微分截面(DDCS),给出了散射电子和敲出电子截面的角分布.散射电子和敲出电子的二重微分截面分别通过敲出电子和散射电子三重微分截面(TDCS)在全空间的角度积分而得到,所有的理论结果与有效的实验测量进行了比较.研究表明:除400和600 ev的高入射能之外,理论结果均能与绝对测量的实验结果较好的符合. 相似文献
969.
在100TW掺钛蓝宝石飞秒激光器上利用光学CCD相机和光学多道分析仪,分别在靶背法线方向测量了超热电子光辐射的空间分布和光谱.测量结果显示:光辐射空间分布图案呈圆环状,而辐射区域有发散角和光强分布,且包含多种辐射成分.光辐射光谱在800nm附近出现尖峰,是激光的基频(ω0)波,这一现象归因于超热电子束在输运的过程中产生的微束团而引起的相干渡越辐射(CTR).随着激光能量的增加,CTR光谱峰向红光方向移动,基频波红移的主要原因是由于等离子体临界面的迅速膨胀.如果考虑超热电
关键词:
超热电子
光辐射
共振吸收
红移 相似文献
970.