974 resultados para Vadianus, Joachim, 1484-1551.
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In study of gene expression profile in cloned embryos which derived from D. rerio embryonic nuclei and G. rarus enucleated eggs, cytochrome c oxidase subunit I (COXI) of G. rarus, exhibiting difference at expression level between cloned embryos and zebrafish embryo, was cloned. Its full cDNA length is 1654 bp and contains a 1551 bp open reading frame, encoding a 5.64 kDa protein of 516 amino acids. The alignment result shows that mitochondrion tRNA(ser) is co-transcripted with COXI, which just was the 3'-UTR of COXI. Molecular phylogenic analysis based on COXI indicates G. rarus should belong to Gobioninae, which was not in agreement with previous study according to morphological taxonomy. Comparison of DNA with cDNA shows that RNA editing phenomenon does not occur in the COXI of G. rarus.
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© 2013 IEEE. This paper reviews the mechanisms underlying visible light detection based on phototransistors fabricated using amorphous oxide semiconductor technology. Although this family of materials is perceived to be optically transparent, the presence of oxygen deficiency defects, such as vacancies, located at subgap states, and their ionization under illumination, gives rise to absorption of blue and green photons. At higher energies, we have the usual band-to-band absorption. In particular, the oxygen defects remain ionized even after illumination ceases, leading to persistent photoconductivity, which can limit the frame-rate of active matrix imaging arrays. However, the persistence in photoconductivity can be overcome through deployment of a gate pulsing scheme enabling realistic frame rates for advanced applications such as sensor-embedded display for touch-free interaction.
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In this paper, we present a study on electrical and optical characteristics of n-type tin-oxide nanowires integrated based on top-down scale-up strategy. Through a combination of contact printing and plasma based back-channel passivation, we have achieved stable electrical characteristics with standard deviation in mobility and threshold voltage of 9.1% and 25%, respectively, for a large area of 1× 1 cm2 area. Through use of contact printing, high alignment of nanowires was achieved thus minimizing the number of nanowire-nanowire junctions, which serve to limit carrier transport in the channel. In addition, persistent photoconductivity has been observed, which we attribute to oxygen vacancy ionization and subsequent elimination using a gate pulse driving scheme. © 2014 IEEE.
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In the design of capacitive touch-screen panels, electrodes are patterned to improve touch sensitivity. In this paper, we analyze the relationship between electrode patterns and touch sensitivity. An approach is presented where simulations are used to measure the sensitivity of touch-screen panels based on capacitance changes for various electrode patterns. Touch sensitivity increases when the touch object is positioned in close proximity to fringing electric fields generated by the patterned electrodes. Three new electrode patterns are proposed to maximize field fringing in order to increase touch sensitivity by purely electrode patterning means. Simulations showed an increased touch sensitivity of up to 5.4%, as compared with the more conventional interlocking diamonds pattern. Here, we also report empirical findings for fabricated touch-screen panels. © 2005-2012 IEEE.
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The choice of the etching depth for semiconductor microcavities is a compromise between a high Q factor and a difficult technique in a practical fabricating process. In this paper, the influences of the etching depth on mode Q factors for mid-infrared quantum cascade microcylinder and microsquare lasers around 4.8 and 7.8 mu m are simulated by three-dimensional (3D) finite-difference time-domain (FDTD) techniques. For the microcylinder and the microsquare resonators, the mode Q factors of the whispering-gallery modes (WGMs) increase exponentially and linearly with the increase in the etching depth, respectively Furthermore, the mode Q factors of some higher order transverse WGMs may be larger than that of the fundamental transverse WGM in 3D microsquares. Based on the field distribution of the vertical multilayer slab waveguide and the mode Q factors versus the etching depth, the necessary etching depth is chosen at the position where the field amplitude is 1% of the peak value of the slab waveguide. In addition, the influences of sidewall roughness on the mode Q factors are simulated for microsquare resonators by 2D FDTD simulation. (C) 2009 Optical Society of America
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Proton-conducting membranes were prepared by polymerization of microemulsions consisting of surfactant-stabilized protic ionic liquid (PIL) nanodomains dispersed in a polymerizable oil, a mixture of styrene and acrylonitrile. The obtained PIL-based polymer composite membranes are transparent and flexible even though the resulting vinyl polymers are immiscible with PIL cores. This type of composite membranes have quite a good thermal stability, chemical stability, tunability, and good mechanical properties. Under nonhumidifying conditions, PIL-based membranes show a conductivity up to the order of 1 x 10(-1) S/cm at 160 degrees C, due to the well-connected PIL nanochannels preserved in the membrane. This type of polymer conducting membranes have potential application in high-temperature polymer electrolyte membrane fuel cells.
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大型海藻的生产力高,生产成本低,是一种理想的能源作物。广东省是我国海洋大省之一,约35万平方公里的海域,海藻物种丰富,为海藻养殖提供了有利的条件。我省是能源消耗大省,大部分依靠外省调入和进口,发展海藻能源技术是缓解能源问题的重要途径之一。目前,海藻作为生物质的利用技术还不成熟。在本论文中,选用我省常见的江蓠、马尾藻和麒麟菜三种的大型的海藻进行热解和发酵实验。 首先,对海藻在不同温度下(400℃~900℃)热解得到的各产物(气体、焦油和残渣)产率和热值以及气体组分进行了分析,研究了各热解产物产率、热值和气体组分随温度的变化规律,分析热解过程中的K、Ca、Na、Mg等元素的析出和迁移规律。用去离子水和稀盐酸对海藻进行洗滤预处理,研究其热解特性,进行热重分析,建立海藻热解的反应动力学模型,并计算海藻的动力学参数。分析结果表明:热解气体中的主要成分为H2、CO、CH4、C2H4、C2H6等,热解气低位热值介于5~15 MJ/m3之间。海藻本身具有灰分含量较高和热值较低的特点,水洗可以有效地脱除部分的碱金属,并可以减少灰分含量,改善海藻的热解特性。 其次,以江蓠和马尾藻为底物进行发酵。结果表明:海藻中含有大量金属阳离子,直接发酵容易溶解到料液中,抑制微生物生长,影响发酵效果。用淡水浸泡以后的海藻能容易进行发酵。江蓠的产气率要高于马尾藻。在发酵温度为35℃,简单破碎,料液浓度为5%的条件下,江蓠TS(总固体)产气率是390.6L/kg 。在55℃,颗粒大小0.6~0.9mm,料液浓度为5%的条件下,马尾藻TS产气率是173.1L/kg。 通过对比海藻热解和发酵过程及结果的比较可以发现,海藻热解产气率低,碱金属容易析出;海藻发酵可以直接利用湿原料,产气率高,但发酵时间较长,需要合适的菌种。在目前没有特殊专有技术的情况下,采用发酵比采用热解实现海藻的能源化利用可能性更大。 最后,对本论文的研究探讨进行总结,并对今后进一步完善该工作提出了建议。
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在人工气候室水培条件下,以玉米(ZeamaysL.)杂交种F1代户单4号及其母本天四和父本478为材料,用细胞压力探针技术研究了正常供水和PEG-6000模拟–0.2MPa水分胁迫条件下,玉米根皮层细胞水分关系参数的基因型差异。结果表明,根皮层细胞的直径、长度和体积均为F1代>母本>父本;正常供水条件下3个玉米品种的根皮层细胞膨压均在0.6MPa左右且品种间差异不显著,水分胁迫抑制了细胞的延伸生长且F1代和母本的细胞膨压显著高于父本;根皮层细胞壁体积弹性模量均为父本>母本>F1代,水分胁迫条件下的品种间差异显著;与正常供水条件相比,水分胁迫条件下细胞膨压显著降低,而弹性模量则大幅度提高;在两种水分条件下,水分跨细胞膜运转的半时间均为父本>母本>F1代,且半时间在水分胁迫条件下均显著高于正常供水条件下;HgCl2处理引起了半时间的延长,2-巯基乙醇则部分逆转了HgCl2的效应;在两种水分条件下,根皮层细胞水导均为F1代>母本>父本且品种间差异显著,水分胁迫则显著降低了细胞水导。试验证明杂交种F1代的细胞水平根系吸水能力优于亲本,体现了杂种优势。