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1.
Seok-June Chae Dae-Su Kim Hero Kim Su-Hwan Go Sun-Woo Kim Eun-Ji Kim Jae-Min Eum In-Su Kim Sahn Nahm 《Journal of the American Ceramic Society》2022,105(2):1185-1197
0.97(Na0.5-xLixK0.5)(Nb0.89Sb0.11)O3-0.03CaZrO3 [(N0.5-xLxK)(NS)-CZ] piezoceramic (x = 0.325) has a pseudocubic-tetragonal-orthorhombic (PC-T-O) multi-structure. The PC structure formed in this piezoceramic was identified as the R3m rhombohedral structure. This piezoceramic showed the large piezoelectric charge constant (d33) of 515 pC/N due to the PC-T-O multi-structure. The NaNbO3 (NN) templates were used to texture the (N0.5-xLxK)(NS)-CZ thick films along the (001) direction, and the textured thick film (x = 0.0375) had a large Lotgering factor of 95.6%. The PC-T-O multi-structure was observed in this thick film (x = 0.0375), but the thick film (x = 0.0325) showed a PC-O structure owing to the diffusion of the NN templates into the thick film. The textured thick film (x = 0.0375) exhibited an increased d33 of 625 pC/N because of the PC-T-O multi-structure and the lineup of grains along the [001] direction. A textured thick film (x = 0.0375) was used to fabricate a planar-type actuator to confirm its applicability to electrical devices. This actuator exhibits large acceleration (580.3 G) and displacement (150 μm) at a low electric field of 0.2 kV/mm with a short response time of 3.0 ms. Therefore, the (N0.5-xLxK)(NS)-CZ thick films are excellent lead-free piezoceramics. 相似文献
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Yeon Jung Park Eun Soo Noh Jung Youn Park Eun Mi Kim Jae Koo Noh Tae-Jin Choi Jung-Ha Kang 《Food Analytical Methods》2018,11(11):3034-3041
In this study, a multiplex PCR detection method was developed to identify the country of origin of Corbicula japonica (clams), a commercially important bivalve in Asia. Specific primer sets that have a single nucleotide mismatch at the 3′ terminus were designed after sequencing the mitochondrial 16S rRNA gene of clams identified as C. japonica originating from Korea, China, and Japan. Using this method, each origin was clearly identified based on the PCR products: three bands for Korean C. japonica (100, 283, and 384 bp), one band for Chinese C. japonica (384 bp), and two bands for Japanese C. japonica (384 and 100 bp). These results indicate that the 16S rRNA gene, which is usually used to identify species, can distinguish the country of origin within C. japonica. Our multiplex PCR assay should be a useful tool for the fair trade of the species. 相似文献
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Electrochemical characterization of laser‐carbonized polyacrylonitrile nanofiber nonwovens 下载免费PDF全文
Dennis Go Martin Opitz Philipp Lott Khosrow Rahimi Jochen Stollenwerk Helga Thomas Martin Möller Bernhard Roling Alexander J. C. Kuehne 《应用聚合物科学杂志》2018,135(25)
Porous carbon materials represent prospective materials for absorbers, filters, and electronic applications. Carbon fibers with high surface areas can be produced from polyacrylonitrile and spun as thin fibers from solution. The resulting polymer fibers are first stabilized to obtain conjugated ribbons and then carbonized to graphitic structures in a second high‐temperature step in an inert atmosphere. In this study, we investigated a previously described fast laser‐heating process that delivered fibers with a higher crystallinity and surface area compared to the thermally carbonized fibers. In a subsequent KOH‐activation step, the crystalline domains were exfoliated, and the surface of the fibers became macroporous. This led to a reduced specific surface area but a higher capacitance compared to thermally carbonized nanofibers. We report the electrochemical properties of the electrochemical cells and discuss their potential applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46398. 相似文献
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This study investigates the effect of viewer engagement on gifting items to a streamer in a live video streaming. Data were collected from AfreecaTV, a leading live video streaming platform in South Korea, to examine viewer engagement and gift-giving behavior. After analyzing 2,294,837 viewers over a three-month period, the empirical results provide evidence that viewer engagement is positively associated with gift-giving decisions. However, the impact of viewer engagement on the amount of gifts purchased is different depending on how the engagement is measured (i.e., by stream or by channel). This study empirically proves that the motive for socialization has a high correlation with gift-giving behavior, which is considered as commoditization of a viewer’s social interaction while consuming media. The study concludes with a discussion on practical implications for live video streaming services and suggestions for future research. 相似文献
6.
Chun Dong Hyun Rhim Geun Bae Youn Min Hye Deviana Deviana Lee Ji Eun Park Ji Chan Jeong Heondo 《Topics in Catalysis》2020,63(9-10):793-809
Topics in Catalysis - Fischer–Tropsch synthesis (FTS) is a promising way to produce clean liquid fuels and high value-added chemicals from low-value carbon-containing resources such as coal,... 相似文献
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M. Gołąbczak P. Maksim P. Jacquet A. Gołąbczak K. Woźniak C. Nouveau 《Materialwissenschaft und Werkstofftechnik》2019,50(5):611-615
In this article the results concerned influence of processing conditions of the wire electrical discharge machining and vibro‐abrasive machining on the surface layer and morphology of samples made of hard machinable materials used in aircraft industry like: Titanium 5553 β, Inconel 617, Hastelloy X and Magnesium AZ31 have been presented. For this purpose the cubic and cylindrical samples made of hard machinable alloys have been prepared using optimal electric parameters of wire‐cut electrical discharge machining and finally they have been polished using circular vibratory finishing technology and different ceramic shaped stones. 相似文献
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Hyun‐Wook Kim Seunghak Oh Seung Hwan Lee Sanghoon Lee Ji‐Eun Na Kea Joo Lee Im Joo Rhyu 《Microscopy research and technique》2019,82(1):25-32
Experience‐dependent synapse remodeling is associated with information storage in the nervous system. Neuronal synapses show alteration in various neurological and cognitive disorders in their structure and function. At the ultrastructural level, parallel fiber boutons contacting multiple spines of Purkinje cells in the cerebellar cortex are commonly observed in physiologically enriched animals as well as pathological ataxic mutants. However, the dendritic origin of those spines on parallel fiber multiple‐synapse boutons (MSBs) has been poorly understood. Here, we investigated this issue by 3‐dimensional ultrastructural analysis to determine synaptic connectivity of MSBs in both mice housed in physically enriched environment and cerebellar ataxic mutants. Our results demonstrated that environmental enrichment selectively induced MSBs to contact spines from the same parent dendrite, indicating focal strengthening of synapse through the simultaneous activation of two adjacent spines. In contrast, ataxic mutants displaying impaired motor coordination had significantly more MSBs involving spines originating from different neighboring dendrites compared to both wild‐type and environmentally enriched animals, suggesting that compromising multiple synapse formation may lead to abnormal motor behavior in the mutant mice. These findings propose that environmental stimulation in normal animals mainly involves the refinement of preexisting synaptic networks, whereas pathological ataxic conditions may results from less‐selective but compromising multiple synaptic formation. This study underscores that different types of multiple synapse boutons may have disparate effects on cerebellar synaptic transmission. 相似文献
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