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51.
H. Segawa S. Yamaguchi Y. Yamazaki T. Yano S. Shibata H. Misawa 《Applied Physics A: Materials Science & Processing》2006,83(3):447-451
Two-dimensional (2D) pillar arrays with submicrometer to micrometer repetitions have been fabricated from hybrid organic–inorganic
material by mask lithography or multi-beam interference lithography. The type of array structure depends on structural parameters
such as the pillar height, diameter and distance between neighboring pillars. Two kinds of periodic arrays, 2D arrays and
‘top-gathering’ arrays, can be obtained by controlling the structural parameters. In the top-gathering arrays, the pillars
are gathered at the top by means of self-organization, and ‘top-gathering’ units composed of four pillars can be formed.
PACS 68.35.Gy; 81.20.Fw; 82.50.-m 相似文献
52.
Fraction collection of selected components from a complex mixture plays a critical role in biomedical research, environmental analysis, and biotechnology. Here, we introduce a novel electrophoretic chip device based on a signal processing theorem that allows simultaneous space sampling for fractionation of ssDNA target fragments. Ten parallel extraction channels, which covered 1.5-mm-long sampling ranges, were used to facilitate the capturing of fast-moving fragments. Furthermore, the space sampling extraction made it possible to acquire pure collection, even from partly overlapping fragments that had been insufficiently separated after a short electrophoretic run. Fragments of 180, 181, and 182 bases were simultaneously collected, and then the recovered DNA was PCR amplified and assessed by CE analysis. The 181-base target was shown to be isolated in a 70-mm-long separation length within 10 min, in contrast to the >50 min required for the 300-mm-long separation channel in our previous study. This method provides effective combination of time and space, which is a breakthrough in the traditional concept of fraction collection on a chip. 相似文献
53.
On-chip fraction collection for multiple selected ssDNA fragments using isolated extraction channels
Li Z Sun K Sunayama M Matsuo Y Mizeikis V Araki R Ueno K Abe M Misawa H 《Journal of chromatography. A》2011,1218(7):997-1003
High efficiency and high-purity fraction collection is highly sought in analysis of fragments-of-interest from selective polymerase chain reaction (PCR) products generated by High Coverage Gene Expression Profiling (HiCEP) methods. Here we demonstrate a new electrophoretic chip device enabling automatic high-efficient fractionation of multiple ssDNA target fragments during a run of separation. We used thoroughly isolated extraction channels for each selected target to reduce the risk of cross-contamination between targets due to cross-talk of extraction channels. Fragments of 35, 108 and 138 b, were successfully isolated, then the recovery was PCR-amplified and assessed by capillary electrophoresis (CE) analysis. Total impurity level of the targets due to unwanted fragments of 0.7%, 2% and 6% respectively, was estimated. Difficulties in collecting multiple target factions are due to band diffusion and DNA adsorption to the walls for the fragments in the separation channel, which is generated by transferring the DNA target fraction from the extraction section to the target reservoir. Therefore, we have carefully measured band broadening and analyzed its influence on the separation resolution due to the delay. 相似文献
54.
55.
本文提出一种基于增量调制(DM)序列的离散傅里叶变换(DFT)结构,它不同于基于脉冲编码调制(PCM)的常规方法。提出这一想法是为了解决在常规的数字信号处理中的乘法运算问题,从而减小系统的复杂性,降低设备成本。我们将看到,本文提出的新的DFT结构取消了A/D变换器和乘法器,可望简化硬件设计、降低造价,而信噪比同样能够达到与常规的处理方法,如FFT相近的结果。计算机模拟表明,对于确定性信号,结果与常规的DFT相一致。对于带限高斯信号,只要适当地选择步长和过采样率系数,同样也能得到与常规DFT相近的结果。我们采用ROM存贮各个系数值,因此,整个运算完全是阅读和求和的过程,因而速度快,硬件结构简单,适用于语音、地震等信号的处理。本文最后给出了硬件实现方案和各个参数的选择方法,同时提供了计算机模拟结果。 相似文献
56.
本文研究多视极化合成孔径雷达(SAR)图象的相干斑抑制,提出多视极化白化滤波(MPWF)法,并进一步将它发展成具有多通道输出的全极化滤波器。本文还定量地分析了MPWF方法抑制相干斑的能力,并在理论上同全功率法、加权法和功率均衡法进行了比较。应用NASA/JPL机载L波段四视全极化SAR数据的试验结果验证了所提方法的有效性和优越性,也说明了MPWF处理能显著地提高SAR图象的分类精度。 相似文献
57.
Inside Back Cover: Plasmon‐Assisted Water Splitting Using Two Sides of the Same SrTiO3 Single‐Crystal Substrate: Conversion of Visible Light to Chemical Energy (Angew. Chem. Int. Ed. 39/2014) 下载免费PDF全文
58.
59.
Yong-Hoon Kim Md. Mashiur Rahman Zhen-Long Zhang Nobuo Misawa Ryugo Tero Tsuneo Urisu 《Chemical physics letters》2006,420(4-6):569-573
The effect of the electrostatic attractive force between giant unilamellar vesicles (GUVs) and the SiO2 surface on the formation of a Ca2+-free supported lipid bilayer (SLB) was investigated by atomic force microscopy and fluorescence microscopy. When negatively charged GUVs were incubated for 1 h without Ca2+, the surface coverage of lipid bilayer was <1% on the SiO2 surface. In contrast, a high coverage was obtained without addition of Ca2+ on the positively charged surface modified by aminopropyldimethylethoxysilane, and the coverage of SLBs decreased with increasing KCl concentrations. The thickness of the water layer under SLB was reduced by modification of APS. 相似文献
60.
This paper considers the optimal spare ordering policies for a cold standby redundant system with two dissimilar units. Especially, the planned maintenance schedule with salvage cost is discussed. The failure time distributions for respective units are assumed to be arbitrary. By applying the expected cost per unit time in the steady-state and the stationary availability as criteria of optimality, the optimal ordering policy minimizing or maximizing each criterion is obtained under some economical and/or physical assumptions. Finally, numerical examples are presented, and the effect of the failure time distributions for the optimal ordering policy is examined in detail. 相似文献