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111.
Molecular dynamics simulations have been performed to investigate the structures of Lennard–Jones(LJ) nanowires(NWs) encapsulated in carbon nanotubes(CNTs). We find that the structures of NWs in a small CNT only adopt multi-shell motifs, while the structures of NWs in a larger CNT tend to adopt various motifs. Among these structures, three of them have not been reported previously. The phase boundaries among these structures are obtained regarding filling fractions, as well as the interaction between NWs and CNTs. 相似文献
112.
113.
Investigation of the limit of lateral beam shifts on a symmetrical metal-cladding waveguide 下载免费PDF全文
This paper reports that Goos--H\"anchen (GH) shifts
occurring on a symmetrical metal-cladding waveguide are
experimentally identified. It was found that there exists a critical
thickness of the upper metal layer, h_cr, above which negative
shift is observed and, reversely, positive shift occurs. Both
positive and negative GH shifts near the critical thickness do not vary
dramatically and can achieve a maximum on the submillimeter scale, which
is different from simulated results using the stationary-phase
method. It also shows that this critical thickness, h_cr, can be
obtained at the position for zero reflectivity by setting the
intrinsic damping to be the same as the radiative damping. The GH
effects observed near the critical thickness are produced by extreme
distortion of the reflected beam profiles, which limits the
amplitude of the GH shift and, further, the sensitivity of the GH optical
sensor based on the symmetrical metal-cladding waveguide. 相似文献
114.
The electronic structures and transport properties of (10,0) single-walled carbon nanotube ((10,0) (SWNT)) with oxygen-containing defect complex are investigated using density functional theory in combination with nonequilibrium Green?s function method. The complex delocalizes the local states of (10,0) SWNT induced by mono- and di-vacancy but strengthens the localization of the states induced by the Stone–Wales defect. As a result, the complex partially restores the transport properties of (10,0) SWNT with vacancies, but reduces the transmission of (10,0) SWNT with Stone–Wales defect. However, the oxygen-containing defect complex only slightly influences the transmission gap and threshold voltage of the system. 相似文献
115.
单壁碳纳米管的快速、高效提纯方法研究 总被引:1,自引:0,他引:1
本文采用改进的流化床装置对碳纳米管进行空气氧化处理、浓盐酸浸泡处理、空气氧化、浓盐酸浸泡组合处理, 利用扫描电镜和拉曼光谱方法检测了四种处理方法对碳纳米管提纯的效果, 结果发现, 在873 K经空气氧化30分钟, 再用浓盐酸浸泡10分钟, 这种组合处理方法下, 得到的单壁碳管纯度最高, 产率最大。 相似文献
116.
提出了一种利用喇曼散射原理的光纤分布式测温系统中基于迭代的高准确度温度解调算法.针对于常规的反斯托克斯-斯托克斯双光路比值的温度解调算法,该迭代算法进一步校正了光纤中双光路衰减系数差对温度敏感带来的温度测量误差,尤其适用于中距离且温度场复杂的测温环境,实现了高准确度的温度测量.通过理论分析确定了该迭代法的迭代格式,测量了相应的光纤参量,并在传感样机上编写相应的代码通过实验予以验证,在0~90℃温度范围,5km测量长度输出的测温曲线符合预期的测温效果. 相似文献
117.
Airborne single-wall carbon nanotubes (SWCNTs) have a high tendency to agglomerate due to strong interparticle attractive
forces. The SWCNT agglomerates generally have complex morphologies with an intricate network of bundles of nanotubes and nanoropes,
which limits their usefulness in many applications. It is thus desirable to produce SWCNT aerosol particles that have well-defined,
unagglomerated fibrous morphologies. We present a method to generate unagglomerated, fibrous particles of SWCNT aerosols using
capillary electrospray of aqueous suspensions. The effects of the operating parameters of capillary electrospray such as strength
of buffer solution, capillary diameter, flow rate, and colloidal particle concentration on the size distributions of SWCNT
aerosols were investigated. Results showed that electrospray from a suspension of higher nanotube concentration produced a
bimodal distribution of SWCNT aerosols. Monodisperse SWCNT aerosols below 100 nm were mostly non-agglomerated single fibers,
while polydisperse aerosols larger than 100 nm had two distinct morphologies: a ribbon shape and the long, straight fiber.
Possible mechanisms are suggested to explain the formation of the different shapes, which could be used to produce SWCNT aerosols
with different morphologies. 相似文献
118.
119.
基于谱间线性滤波的高光谱图像压缩感知 总被引:1,自引:1,他引:1
根据高光谱图像较强的谱间相关性,提出一种基于谱间线性滤波的高光谱图像压缩感知方法.高光谱图像进行压缩重构时,利用相邻波谱的谱间相关性,对重构的当前帧与前一谱段的重构图像进行谱间线性滤波,降低了重构帧的噪音信息,纠正了重构帧的轮廓信息,从而提高重构质量.在进行谱间线性滤波时,保留重构帧的低频系数,高频系数与前一波谱重构图像的高频小波变换系数进行线性加权求和,达到滤波的效果.通过实验表明,该方法能够有效提升图像重构质量,并降低重构时间. 相似文献
120.
T Matsuno K Maruyama J Tsutsui 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2012,88(7):368-384
The concept of "stabilization" of atmospheric CO2 concentration is re-examined in connection with climate-change mitigation strategies. A new "zero-emissions stabilization (Z-stabilization)" is proposed, where CO2 emissions are reduced to zero at some time and thereafter the concentration is decreased by natural removal processes, eventually reaching an equilibrated stable state. Simplified climate experiments show that, under Z-stabilization, considerably larger emissions are permissible in the near future compared with traditional stabilization, with the same constraint on temperature rise. Over longer time scales, the concentration and temperature decrease close to their equilibrium values, much lower than those under traditional stabilization. The smaller temperature rise at final state is essential to avoid longer-term risk of sea level rise, a significant concern under traditional stabilization. Because of these advantages a Z-stabilization pathway can be a candidate of practical mitigation strategies as treated in Part 2.(Contributed by Taroh MATSUNO, M.J.A.). 相似文献