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71.
Hiroaki Takeda Tomoaki Kuze Takashi Nishida Kiyoshi Uchiyama Tadashi Shiosaki 《Materials Research Bulletin》2008,43(7):1731-1736
The influences of aluminum substitution for gallium in the langasite-type La3Nb0.5Ga5.5O14 (LNG) crystals on their growth and electric properties were investigated. Al-substituted LNG (La3Nb0.5Ga5.5−xAlxO14; LNGAx) single crystals up to the solubility limit x = 0.2 have been grown by the conventional Czochralski technique. The electric properties of the LNGAx crystals were investigated and compared to those of LNG. With Al substitution, the piezoelectric constants, d11 and d14, were slightly higher. The LNGAx crystals showed a temperature dependence of d11 similar to that of the LNG crystal. 相似文献
72.
Silicon rubber, PDMS, was irradiated by Ar, Ar/H2 and Ar/O2 plasmas to increase the surface wettability to water which was found to increase with the irradiation time for every application of plasma irradiation. The use of Ar/O2 plasma was found to be particularly effective in enhancing the surface wettability. The aging behavior due to exposure to air, ethanol or water was also measured. In the case of continuous exposure to water after plasma treatment, the wettability could be maintained for more than several months with the water immersion. 相似文献
73.
Recently, Echo-MIMO, a delay-free feedback scheme has been proposed for Closed-Loop MIMO systems, where the receiver echoes
the received signal on the fly to the transmitter without any processing. While this reduced feedback latency allows for more
use of the channel’s coherence time for data transmission, it comes at high power-and-bandwidth costs, as two MIMO transmissions
are required in the feedback phase. In this paper, we present a feedback scheme that preserves the advantages of Echo-MIMO
while requiring only one feedback transmission. The echoed signals are judiciously combined with the receiver’s signals such
that their separation at the transmitter be lossless, and that no extra transmit power nor bandwidth be required. In addition,
we highlight the estimation accuracy degradation in Echo-MIMO owing to the echoed noise, and analytically confirm the intuition
that removing the noise prior to echoing the received signal provides better estimation than echoing the noisy received signal
as is and later account for the noise effect upon echo reception. Simulation results show that the proposed scheme outperforms
Echo-MIMO in terms of channel estimation accuracy and achievable capacity. 相似文献
74.
Chiba T Wauke T Sadamasu K Yano K Morozumi S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2007,48(1):1-7
The identification of 20 strains of yeasts isolated from foods by means of DNA sequence analysis with two kinds of universal primers for the rDNA region was examined, and the results were compared with those of the conventional phenotyping test using API 20C AUX. In the analysis of the 26S region, all 20 yeast strains tested were identified at the species level. In the ITS1 region, 16 strains were also classified at the species level. In addition, all results of DNA sequence analysis were consistent with those of the phenotyping test at the genus level. Furthermore, DNA sequence analysis was able to identify causative yeasts observed in two suspect foods, though phenotyping tests alone failed to identify them. 相似文献
75.
76.
Tsutsumi T Amakura Y Sasaki K Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2007,48(1):8-12
We examined the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) in muscle and gut tissues from Japanese common squid and saury. These body parts are often eaten in Japan, so it is important to measure their dioxin concentrations and evaluate the risks to consumers. The toxic equivalent (TEQ) concentrations in the squid gut samples (1.0 to 14 pg-TEQ/g fresh weight, n=3) were 50-fold larger than those in the muscle tissues (0.020 to 0.22 pg-TEQ/g fresh weight, n = 3) taken from the same samples. By contrast, the TEQ concentrations in the saury gut samples (0.35 to 0.63 pg-TEQ/g fresh weight, n=3) were only 1.1- to 1.7-fold greater than those in the muscle tissues (0.33 to 0.37 pg-TEQ/g fresh weight, n= 3) from the same samples. The TEQ contents in the squid gut tissues ranged from 60 to 990 pg-TEQ/squid, accounting for about 95% of the total dioxin content of the edible parts of the samples. By contrast, the TEQ contents in the saury gut tissues ranged from 4.4 to 12 pg-TEQ/saury, accounting for less than 25% of the total dioxin content of the edible parts of the samples. These tissues showed comparable PCDD/PCDF-congener and dioxin-like PCB-isomer profiles in both species. The results indicate that squid gut tissues occasionally contain high levels of dioxins, and consumption of this foodstuff could potentially significantly increase the dietary intake of dioxins. 相似文献
77.
Youngkook Kim Fumiaki MitsugiIkegami Tomoaki Kazuyuki HokamotoShigeru Itoh 《Journal of the European Ceramic Society》2011,31(6):1033-1039
Titanium dioxide (TiO2) bulk with pure anatase phases was fabricated by an explosive compaction technique using an underwater shockwave. Dynamic shock pressure of 6 GPa was used to consolidate anatase TiO2 powders. Its microstructural, crystalline structural and photocatalytic characteristics were observed and measured by various techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and photocatalytic activity measurement system. It was confirmed that the relative density of anatase TiO2 compact is about 96% (3.73 g/cm3) of the theoretical density (3.89 g/cm3) and a strong surface bonding between particles is formed by a shock energy. In X-ray diffraction analysis, high purity anatase phases, broadened peaks due to lattice defects and decreased crystallite size were found. For the photocatalytic activities, the anatase TiO2 compact was quite excellent compared to the commercial sintered TiO2 bulk. 相似文献
78.
Yanagida H Matsuura T Kazuta Y Yomo T 《Chembiochem : a European journal of chemical biology》2011,12(6):962-969
There is a great deal of interest in proteins that can bind covalently to target molecules, as they allow unambiguous experiments by tight binding to molecules of interest. Here, we report the generation of proteins that undergo covalent labeling with small molecules through in vitro selection by using ribosome display. Selection was performed from a mutant library of the WW domain with a biotinylated peptide as its binding target, in which the biotin and the peptide are connected by a disulfide bond. After five rounds of selection, we identified mutants carrying a particular cysteine mutation. The binding target reacted specifically with the selected mutant, even in the presence of other proteins, and resulted in the generation of biotin- or peptide-labeled WW domains by thiol-disulfide exchange. When the mutant was fused to a protein of interest, the fusion protein was also labeled with biotin. Thus, the characteristics of the selected mutant should be suitable as a tag sequence that can be covalently labeled with small synthetic molecules. These results indicate that the rapid and efficient generation of such proteins is possible by ribosome display. 相似文献
79.
Hiromi Nabeshi Tomoaki Yoshikawa Akihiro Arimori Tokuyuki Yoshida Saeko Tochigi Toshiro Hirai Takanori Akase Kazuya Nagano Yasuhiro Abe Haruhiko Kamada Shin-ichi Tsunoda Norio Itoh Yasuo Yoshioka Yasuo Tsutsumi 《Nanoscale research letters》2011,6(1):1-6
In this study, complexes composed of poly-l-tyrosine (pLT) and single-walled carbon nanotubes (SWCNTs) were produced and the dispersibility of the pLT/SWCNT complexes in water by measuring the ζ potential of the complexes and the turbidity of the solution were investigated. It is found that the absolute value of the ζ potential of the pLT/SWCNT complexes is as high as that of SWCNTs modified with double-stranded DNA (dsDNA) and that the complexes remain stably dispersed in the water at least for two weeks. Thermogravimetry analysis (TGA) and visualization of the surface structures of pLT/SWCNT complexes using an atomic force microscope (AFM) were also carried out. 相似文献
80.
Wei Liu Hiroki Nishiyama Nei Kato Yoshitaka Shimizu Tomoaki Kumagai 《International Journal of Wireless Information Networks》2013,20(3):195-203
Wireless mesh networks (WMNs) have attracted much attention due to their low up-front cost, easy network deployment, stable topology, robustness, reliable coverage, and so forth. These advantages are suitable for the disaster recovery applications in disaster areas, where WMNs can be advantageously utilized to restore network collapse after the disaster. In this paper, based on a new network infrastructure for WMNs, to guarantee high network performance, we focus on the issue of throughput optimization to improve the performance for WMNs. Owing to selecting different mesh router (MR) as the gateway will lead to different network throughput capacity, we propose a novel gateway selection technique to rapidly select the optimal MR as the gateway, in order to maximize the network throughput. In addition, we take into account the traffic distribution for the MR to eliminate traffic congestion in our method. The performance of our proposed method is evaluated by both numerical and simulated analysis. The simulation results demonstrate that the gateway selection method is effective and efficient to optimize the throughput for WMNs. 相似文献