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31.
Md Sazzadur Rahman MD Nahin Islam Shiblee Kumkum Ahmed Ajit Khosla Jun Ogawa Masaru Kawakami Hidemitsu Furukawa 《大分子材料与工程》2020,305(9)
In this work, 3D printable gel polymer electrolytes (GPEs) based on N,N‐dimethylacrylamide (DMAAm) and polyvinylidene fluoride (PVDF) in lithium chloride containing ethylene glycol solution are synthesized and their physicochemical properties are investigated. 3D printing is carried out with a customized stereolithography type 3D gel printer named “Soft and Wet Intelligent Matter‐Easy Realizer” and free forming GPE samples having variable shapes and sizes are obtained. Printed PVDF/PDMAAm‐based GPEs exhibit tunable mechanical properties and favorable thermal stability. Electrochemical proprieties of the printed GPEs are carried out via impedance spectroscopy in the temperature range of 25–90 °C by varying PVDF content. Ionic conductivity as high as 6.5 × 10?4 S cm?1 is achieved at room temperature for GPE containing low PVDF content (5 wt%) and conductivity of the GPEs is increased as temperature rises. 相似文献
32.
We investigate the carrier transport and optical properties of a thick InGaN single quantum well (SQW) where an AlGaN delta-layer is embedded. By way of simulation, it is found that the carrier density distribution in the active region is more uniform in such a QW structure, compared to a double QW (DQW) configuration showing a discontinuity in the hole quasi-Fermi level due to the large effective mass of the holes along with the strong piezoelectric field. Through the photoluminescence (PL) measurements, we have shown that the PL peak energy varies depending sensitively on the delta-layer thickness, providing an extra degree of freedom in the wavelength-tuning control. In particular, such a QW structure is highly desired for long-wavelength emission as the wavelength tuning can be achieved with lower indium composition. The embedded delta-layer also increases the wave function overlap between holes and electrons, thereby shortening the PL lifetime. The results of PL measurements are shown to be consistent with the self-consistent numerical results. A possible application of the proposed QW structure is to the design of long-wavelength light-emitting diodes and laser diodes 相似文献
33.
This paper proposes a method for automatic design of the sensory morphology of a mobile robot. The proposed method employs two types of adaptations, ontogenetic and phylogenetic, to optimize the sensory morphology of the robot. In ontogenetic adaptation, reinforcement learning searches for the optimal policy, which is highly dependent on the sensory morphology. In phylogenetic adaptation, a genetic algorithm is used to select morphologies with which the robot can learn tasks faster. Our proposed method was applied to the design of the sensory morphology of a line‐following robot. We performed simulation experiments to compare the design solution with a hand‐coded robot. The results of the experiments revealed that our robot outperformed the hand‐coded robot in terms of the following accuracy and learning speed, although our robot had fewer sensors than the hand‐coded one. We also built a physical robot using the design solution. The experimental results revealed that this physical robot used its morphology effectively and outperformed the hand‐coded robot. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(1): 48–57, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20965 相似文献
34.
Pu J Nemoto S 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(2):339-344
The off-axis and on-axis spectra in the far zone of an aperture for the case in which a particular class of partially coherent light with a broad spectrum is diffracted by an aperture are studied. It is shown that the spectrum in the far zone is generally different from that at the aperture; i.e., the spectrum is split into two or more peaks. Moreover, the spectrum varies with the diffractive angle. For a fixed diffractive angle, the spectral shift, defined as the difference between the frequencies at which the observed spectrum and the spectrum at the aperture take their maximum, shows a gradual change with the change in the coherence at the aperture. However, as the coherence reaches some critical values, the spectral shift exhibits a rapid transition; i.e., spectral switch occurs. The coherence that causes the spectral switch to take place is different for different diffractive angles. Therefore we propose a new kind of 1 x N spectral switch, where N detectors (output ports) are placed at different diffractive angles in the far zone, and the spectral shifts at different detectors are measured. By adjusting the coherence of the aperture (input port) to the desired values, we obtain a rapid transition of the spectral shift in the desired output ports. 相似文献
35.
A chromatographic determination method was developed for the absolute configuration of an acyclic secondary alcohol using the characteristic functions of 1,5-difluoro-2,4-dinitrobenzene (FFDNB). This method relies on the formation of the fixed favorable conformation of a secondary alcohol-DLA (2,4-dinitrophenyl-5-leucinamide) derivative and its recognition by ODS silica gel. The secondary alcohol reacted first with FFDNB under mild basic conditions, and L-leucinamide or DL-leucinamide was then introduced into the secondary alcohol-FDNB derivative. Because the conformations of the resulting alcohol-DLA derivatives were rigidly fixed by the dinitrobenzene plane, the absolute configuration at the asymmetric carbon of the secondary alcohol tested can be definitely deduced by the elution behavior of both of the diastereomers in the HPLC and/or LC/MS. One of the diastereomers has the cis (Z)-type arrangement of two more hydrophobic substituents of the alcohol and leucinamide moieties, the more hydrophobic side chain and isobutyl groups, to the plane of the dinitrobenzene, whereas another diastereomer has the opposite arrangement (trans (E)-type). Therefore, the cis arrangement interacts more strongly with the ODS silica gel and has a longer retention time than that of the trans-type arrangement. This established method was successfully applied to various chiral acyclic secondary alcohols including chloramphenicol and 4-hydroxyphenyllactic acid. Finally, the limitations of this method were also examined. 相似文献
36.
DJ Drake RS Jensen J Busch-Petersen JK Kawakami M Concepcion Fernandez-Garcia P Fan A Makriyannis MA Tius 《Canadian Metallurgical Quarterly》1998,41(19):3596-3608
The stereoelectronic requirements for interaction of the southern aliphatic hydroxyl of cannabimimetic pharmacophores with the CB1 and CB2 receptors are explored. The stereoselective syntheses of three series of classical/nonclassical hybrid cannabinoids are described. These compounds were designed to investigate the importance of the southern aliphatic hydroxyl (SAH) pharmacophore for cannabimimetic activity. Variation in the chain length of the SAH moiety in these 6beta-(hydroxyalkyl)dihydrobenzopyran analogues, from 6beta-hydroxymethyl to 6beta-(omega-hydroxyethyl) and 6beta-(omega-hydroxypropyl), and the effects of replacing the hydroxyl functionality by hydride and iodide are reported. Our results indicate that the SAH pharmacophore has less pronounced effects than the C-3 aliphatic chain on cannabinoid activity. Furthermore, it appears that this southern molecular component is capable of interacting with two different subsites on the receptor and that the nature of this interaction is determined by the terminal substituent on the C-6beta alkyl group. One of the subsites can accommodate the relatively polar SAH pharmacophore, while the second subsite interacts with more hydrophobic C-6beta substituents and can accommodate large spherical pharmacophores separated by three methylene carbons from the tricyclic cannabinoid template. 相似文献
37.
F Kawakami H Okamura Y Tamada T Nakajima Y Ibata 《Canadian Metallurgical Quarterly》1995,200(3):171-174
Photic stimulus and serotonin (5-hydroxytryptamine; 5-HT) are two factors known to regulate vasoactive intestinal peptide (VIP) synthesis in the suprachiasmatic nucleus (SCN). To explore the role of 5-HT in the photic stimulus-induced change in VIP synthesis, we investigated the changes in level of VIP mRNA under a 12 h light/12 h dark cycle following depletion of 5-HT by intraperitoneal administration of p-chlorophenylalanine (PCPA) methyl ester (200 mg/kg concentration) for 3 successive days. To estimate VIP mRNA expression, we performed in situ hybridization using imaging plates combined with microcomputer-based imaging analysis. In light-phase, total signals of VIP mRNA from the PCPA-treated rats showed a significant decrease compared with those from the saline-treated control rats. However, in dark-phase, there were no significant decreases between the PCPA-treated rats and the saline-control rats. The present results strongly suggest that 5-HT neuronal inputs to the SCN interfere with the effect of photic stimulus on VIP synthesis at the mRNA level. 相似文献
38.
This paper deals with the improvements in response time and reliability of the aWO3/LiClO4-PC (propylene carbonate) electrochromic display. Response time was improved by adopting the highly porous a-WO3 film, the porous reflector and the high surface area non-polarizable counter-electrode. Results from the reliability tests indicated that the ECD had a sufficient lifetime for practical applications such as in watches, clocks and calculators. The mechanism of performance drift upon cycling the display is investigated using ESCA, AES and atomic absorption methods. 相似文献
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