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991.
J.C. Ribierre M. Sato A. Ishizuka T. Tanaka S. Watanabe M. Matsumoto S. Matsumoto M. Uchiyama T. Aoyama 《Organic Electronics》2012,13(6):999-1003
We report on the fabrication and the characterization of p-type organic field-effect transistors based on vapor-deposited J-aggregate bisazomethine dye thin films. The absorption spectra of this non-ionic organic semiconductor in the solid state show a strong influence of the film thickness on the J-aggregate formation. However, the electrical characteristics of the devices demonstrate that the hole transport properties do not vary significantly in films thicker than 100 nm. This is due to the fact that the J-aggregates are formed in this material at the surface of the crystalline grains and do not influence the semiconductor/gate dielectric interface and the charge transport properties of the devices. Hole field-effect mobilities as high as 2.4 × 10?4 cm2 V?1 s?1 were obtained and could be slightly improved by a solvent vapor treatment due to changes in the film crystallinity. Overall, this study demonstrates that J-aggregate bisazomethine dye thin films are good candidates for the realization of organic electronic devices. 相似文献
992.
We describe new heterologous modules for PCR-based gene targeting in the fission yeast Schizosaccharomyces pombe. Two bacterial genes, hph and nat, which display dominant drug-resistance phenotypes, are used as new selectable markers in these modules. Both genes have been used successfully in the budding yeast Saccharomyces cerevisiae, in which hph confers resistance to hygromycin B, while nat confers nourseothricin resistance (Goldstein and McCusker, 1999). Vector modules for gene disruption and C-terminal tagging with 3HA, 13Myc and GFP(S65T) are constructed using previously constructed pFA6a-MX6-derived plasmids (B?hler et al., 1998; Wach et al., 1997). In combination with the existing systems that are based upon the G418-resistance gene (kan), triple gene deletions or tags could be constructed. In addition a vector for one-step integration of a monomeric RFP (mRFP) to the C-terminus of proteins of interest is developed. Finally, oligonucleotides that allow a simple marker switch from kan to hph or nat, and vice versa, are described. The new constructs developed here should facilitate post-genomic molecular analysis of protein functions in fission yeast. 相似文献
993.
Dioscin Derived from Solanum melongena L. “Usukawamarunasu” Attenuates α‐MSH–Induced Melanogenesis in B16 Murine Melanoma Cells via Downregulation of Phospho‐CREB and MITF 下载免费PDF全文
994.
Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures 总被引:1,自引:0,他引:1
995.
Nakai M Ito J Sato K Noguchi J Kaneko H Kashiwazaki N Kikuchi K 《Reproduction (Cambridge, England)》2011,142(2):285-293
In pigs, although ICSI is a feasible fertilization technique, its efficiency is low. In general, injected pig sperm are insufficient to induce oocyte activation and embryonic development. Pretreatments for disrupting sperm membranes have been applied to improve the fertility of ICSI oocytes; however, we hypothesize that such pretreatment(s) may reduce the ability of the sperm to induce oocyte activation. We first evaluated the effects of sperm pretreatments (sonication (SO) to isolate the sperm heads from the tails, Triton X-100 (TX), and three cycles of repeated freezing/thawing (3×-FT) for disrupting sperm membranes) on the rate of pronucleus (PN) formation after ICSI. We found that oocytes injected with control (whole) sperm had higher rates of PN formation than those obtained after subjecting the sperm to SO, TX, and 3×-FT. The amounts of phospholipase Cζ (PLCζ), which is thought to be the oocyte-activating factor in mammalian sperm, in sperm treated by each method was significantly lower than that in whole untreated sperm. Furthermore, using immunofluorescence, it was found that in pig sperm, PLCζ was localized to both the post-acrosomal region and the tail area. Thus we demonstrated for the first time that sperm pretreatment leads to a reduction of oocyte-activating capacity. Our data also show that in addition to its expected localization to the sperm head, PLCζ is also localized in the tail of pig sperm, thus raising the possibility that injection of whole sperm may be required to attain successful activation in pigs. 相似文献
996.
Potassium tungsten oxide nanofibers were successfully synthesized via a facile hydrothermal reaction route in the presence of sulfate. After reduction under a reductive atmosphere of H(2)(5 vol %)/N(2), the potassium tungsten oxide transformed to potassium tungsten bronze. Because of the lack of free electrons, the potassium tungsten oxide (K(x)WO(3+x/2)) showed no NIR shielding performance; however, the potassium tungsten bronze (K(x)WO(3)) showed promising optical characteristics such as high transmittance for visible light, as well as high shielding performance for near-infrared lights, indicating its potential application as a solar filter. Meanwhile, the potassium tungsten bronze (K(x)WO(3)) showed strong absorption of near-infrared light and instantaneous conversion of photoenergy to heat. 相似文献
997.
Yanai N Kitayama K Hijikata Y Sato H Matsuda R Kubota Y Takata M Mizuno M Uemura T Kitagawa S 《Nature materials》2011,10(10):787-793
The development of a new methodology for visualizing and detecting gases is imperative for various applications. Here, we report a novel strategy in which gas molecules are detected by signals from a reporter guest that can read out a host structural transformation. A composite between a flexible porous coordination polymer and fluorescent reporter distyrylbenzene (DSB) selectively adsorbed CO? over other atmospheric gases. This adsorption induced a host transformation, which was accompanied by conformational variations of the included DSB. This read-out process resulted in a critical change in DSB fluorescence at a specific threshold pressure. The composite shows different fluorescence responses to CO? and acetylene, compounds that have similar physicochemical properties. Our system showed, for the first time, that fluorescent molecules can detect gases without any chemical interaction or energy transfer. The host-guest coupled transformations play a pivotal role in converting the gas adsorption events into detectable output signals. 相似文献
998.
Tadashi C Ozawa Katsutoshi Fukuda Yasuo Ebina Kosuke Kosuda Akira Sato Yuichi Michiue Keiji Kurashima Takayoshi Sasaki 《Science and Technology of Advanced Materials》2011,12(4)
La–Eu solid solution nanosheets La2/3−xEuxTa2O7 have been synthesized, and their photoluminescence properties have been investigated. La2/3−xEuxTa2O7 nanosheets were prepared from layered perovskite compounds Li2La2/3−xEuxTa2O7 as the precursors by soft chemical exfoliation reactions. Both the precursors and the exfoliated nanosheets exhibit a decrease in intralayer lattice parameters as the Eu contents increase. However, there is a discontinuity in this trend between the nominal Eu content ranges x≤ 0.3 and x ≥ 0.4. This discontinuity is attributed to the difference in degree of TaO6 octahedra tilting for the La- and Eu-rich phases. La2/3−xEuxTa2O7 nanosheets exhibit red emission, characteristic of the f–f transitions in Eu3+ photoactivators. The photoluminescence emission can be obtained from both host and direct photoactivator excitation. However, photoluminescence emission through host excitation is much more dominant than that through direct photoactivator excitation, and this behavior is consistent with that of all the other rare-earth photoactivated nanosheets reported previously. The absolute photoluminescence quantum efficiency of the La2/3−xEuxTa2O7 nanosheets increases as the experimentally determined Eu contents increase up to x=0.45 and decrease above it. This result is in good agreement with the optimum photoactivator concentration expected from the percolation theory. These solid solution La2/3−xEuxTa2O7 nanosheets are excellent models for validating the theory of optimum photoactivator concentration in the truly two-dimensional photoactivator matrix. 相似文献
999.
NiO-Ce0.8Sm0.2O1.9 (NiO-SDC) nanocomposite powders applied as promising anode material for low-temperature solid oxide fuel cells (SOFCs) were synthesized by hydroxide co-precipitation method using NH3 x H2O, NaOH and NH3 x H2O + NaOH as precipitation agents. The crystal phases, morphologies and sintering behavior of the synthesized NiO-SDC nanocomposite powders were investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM) and sintering experiments. The effect of precipitation agents on the synthesis of the NiO-SDC nanocomposite powders was discussed. Results show that different precipitation agents influence greatly the synthesis and characteristics of the NiO-SDC nanocomposite powders. The NiO-SDC nanocomposite powders synthesized with NH3 x H2O deviate from the original composition due to the loss of Ni. The loss of Ni is avoided and nano-sized NiO-SDC composite powders are synthesized, when NaOH and NH3 x H2O + NaOH are used as precipitation agents. The NiO-SDC nanocomposite powders can be synthesized at relatively low temperature using NH3 x H2O + NaOH as precipitation agent, and the synthesized NiO-SDC nanocomposite powders show good sintering characteristics. 相似文献
1000.