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961.
Emmanuel Chekwube Ossai Takashi Kuroiwa Kaname Horikoshi Yuya Otsuka Junki Terasawa Akihiko Kanazawa Seigo Sato Sosaku Ichikawa 《Journal of the American Oil Chemists' Society》2019,96(12):1405-1416
We studied the effects of emulsifiers on the entrapment yields of a hydrophilic material, calcein, in lipid vesicles formed using the multiple emulsion method. The primary emulsion (W1/O) was prepared via sonication while the secondary emulsification that produced the W1/O/W2 multiple emulsions was achieved using the microchannel (MC) emulsification technique. The emulsifiers used in the continuous (W2) phase were Tween® 80, Pluronic® F68, and bovine serum albumin (BSA). Lipid vesicles formed via solvent evaporation of the multiple emulsion droplets had an average diameter of about 180 nm, similar to the size of the water droplets in the primary W1/O emulsions. The entrapment yields of calcein increased with decreasing concentrations of Tween® 80 but decreased with decreasing concentrations of Pluronic® F68 and BSA. The effects of type and concentration of emulsifier were considered in relation to three possible mechanisms: (i) destabilization/solubilization of lipid bilayers by emulsifiers, (ii) reversed-micellar transport of W1 contents from internal to external water phases through the O phase, and (iii) release of inner water (W1) contents into the continuous (W2) phase via the instability of W1/O/W2 and leakage of W1 contents. Using the food grade emulsifier Tween® 80 at a low concentration of about 0.1 or 0.05 wt%, calcein as a model hydrophilic material could be efficiently entrapped (ca. 80%) in homogenously dispersed lipid vesicles. 相似文献
962.
An assemble‐type plate reactor was developed and its intensified heat transfer compared to that of a conventional tubular reactor in methane reforming was confirmed. This characteristic enables accurate reaction kinetic analysis because of quasi‐isothermal operation with mild pressure loss. Reduced experiment cost is one of the features of the assemble‐type reactor. Simple thermal design equations applicable to plate reactors were also assessed. From experiments and accurate reaction analysis using the plate reactor it is suggested that H2O and CO2 have similar reactivity for a commercial Ni/α‐Al2O3 catalyst. The partial pressure of the oxidizing agent had much more influence on the reactivity of methane reforming than the species of this agent. 相似文献
963.
Dr. Hidetomo Yokoo Motoharu Hirano Dr. Takashi Misawa Dr. Yosuke Demizu 《ChemMedChem》2021,16(8):1226-1233
Antimicrobial peptides (AMPs) are potential novel therapeutic drugs against microbial infections. Most AMPs function by disrupting microbial membranes because of their amphipathic properties and ordered secondary structures. In this minireview, we describe recent efforts to develop helical AMP foldamers containing non-proteinogenic amino acids, such as α,α-disubstituted α-amino acids, β-amino acids, γ-amino acids, side-chain stapling and N-alkyl glycines. 相似文献
964.
Yunzi Xin Yuya Takeuchi Mirai Hattori Takashi Shirai 《Journal of the European Ceramic Society》2019,39(14):4440-4444
In this work, we present the fabrication of alumina/nano-carbon ceramic composite displaying enhanced electrical conductivity through facile iodine impregnation of gel-casted alumina body. Following the previously developed novel fabrication process of alumina/nano-carbon composite having a highly uniform nano-carbon network and superior semi-conductive properties via reductive sintering of gel-casted alumina body under inert atmosphere, we extended the process through the facile impregnation of gel-casted body in iodine solution resulting in enhancement of the amount of nano-carbon, graphitization degree, electrical conductivity and carrier density. The effect of iodine concentration on the properties of alumina/nano-carbon as well as the mechanism for enhanced electrical performance are also systematically investigated. 相似文献
965.
Youfeng Lai Hong Cheng Zhenglin Jia Qizhong Li Meijun Yang Song Zhang Mingxu Han Rong Tu Takashi Goto Lianmeng Zhang 《Journal of the American Ceramic Society》2019,102(9):5668-5678
An ultraviolet laser (λ = 266 nm) operated in pulsed mode and a diode laser (λ = 1060 nm) operated in continuous mode were simultaneously applied to create a hybrid laser chemical vapor deposition (CVD) approach. Fine-grained 3C-SiC thick films were prepared via hybrid laser CVD by using SiCl4, CH4 and H2 as precursors. The effects of the ultraviolet laser on the preferred orientations, microstructures, microhardness values and deposition rates of 3C-SiC thick films were investigated. The 3C-SiC thick films that were prepared at 4 kPa via diode laser CVD exhibited <110>-orientations and 5-100 µm grain sizes, whereas those prepared via hybrid laser CVD were randomly oriented with 0.5-5 µm grain sizes. Compared to diode laser CVD, the additional irradiation of the ultraviolet laser in the hybrid laser CVD improved the Vickers microhardness values of the 3C-SiC thick films from 30 to 35 GPa, and the maximum deposition rate was also increased from 935 to 1230 µm/h. 相似文献
966.
Tomoyuki Hirano Shuhei Nakakura Febrigia Ghana Rinaldi Eishi Tanabe Wei-Ning Wang Takashi Ogi 《Advanced Powder Technology》2018,29(10):2512-2520
Highly crystalline and hexagonal single-phase cesium tungsten bronze (Cs0.32WO3) nanoparticles were successfully synthesized by a flame-assisted spray pyrolysis followed by annealing under a reducing gas atmosphere. The resulting Cs0.32WO3 nanoparticles featured a pure hexagonal Cs0.32WO3 phase with a high crystallinity and homogeneous chemical composition. Unlike conventional methods, the proposed process in this paper has several advantages, including a short reaction time and the ability to yield products with high purity and good energy efficiency. Furthermore, the Cs0.32WO3 nanoparticles produced in this research showed a remarkable near-infrared shielding ability with a 97.7% cut-off at 1500?nm. 相似文献
967.
Structural and Multidisciplinary Optimization - Estimating unknown parameters or conditions based on observation in a numerical model is a problem considered in data assimilation. In this study, we... 相似文献
968.
Takashi Kodama Hiroshi Kinuhata Yuki Shibata Mikio Kumagai Kazunori Suzuki Shin-Itiro Hayashi 《Journal of Nuclear Science and Technology》2020,57(9):1101-1110
ABSTRACT NO2 and NO generated during a boiling and drying accident, which affects the release of volatilized radioactive Ru into the atmosphere, were examined using various samples including simulated high-level liquid waste and a thermogravimetric analyzer. NO2 and NO in the gas flowing out of the analyzer were measured separately using a NOx analyzer equipped with NO2 and NO sensors. The samples were heated to 600°C at constant heating rates of mainly 0.2 and 1°C min?1 that was adopted taking into account the decay heat of high-level liquid waste. It was found that under 180°C some nitrates in the liquid waste mainly separated their nitrate groups as HNO3 without generating NOx (a mixture of NO and NO2) and above 300°C the residual HNO3 in the waste participated in thermal decomposition generating NOx. The generation rates of NO2 and NO were obtained as a function of time using Arrhenius type equations, and the O2 rate was derived from these equations using the stoichiometry of the reactions that generate NO2, NO, and O2. 相似文献
969.
Sang‐Kwon Lee Won‐Yong Lee Takashi Kikkawa Chinh Tam Le Min‐Sung Kang Gil‐Sung Kim Anh Duc Nguyen Yong Soo Kim No‐Won Park Eiji Saitoh 《Advanced functional materials》2020,30(35)
The spin current is significantly limited by the spin‐orbit interaction strength, material quality, and spin‐mixing conductance at material interfaces. Such limitations lead to spin current decay at the interfaces, which severely hinders potential applications in spin‐current‐generating thermoelectric devices. Thus, methodical studies on the enhancement of spin currents are indispensable. Herein, a novel approach for enhancing the spin current injected into a normal metal, Pt, using interface effects with a ferromagnetic insulator, yttrium iron garnet (YIG), is demonstrated. This is accomplished by inserting atomically thin monolayer (ML), tungsten diselenide (WSe2) between Pt and YIG layers. A comparative study of longitudinal spin Seebeck effect (LSSE) measurements is conducted. Two types of ML WSe2 (continuous and large‐area ML WSe2 and isolated ML WSe2 flakes) are used as intermediate layers on YIG film. Notably, the insertion of ML WSe2 between the Pt and YIG layers significantly enhances the thermopower, VLSSE/ΔT by a factor of approximately 5.6 compared with that of the Pt/YIG reference sample. This enhancement in the measured LSSE voltages in the Pt/ML WSe2/YIG trilayer can be explained by the increased spin‐to‐charge conversion at the interface owing to the large spin‐orbit coupling and improved spin mixing conductance with the ML WSe2 intermediate layer. 相似文献
970.
Asep Bustanil Aripin Takashi Yamamoto Makoto Nishi Kunio Hayakawa 《Polymer-Plastics Technology and Engineering》2020,59(12):1308-1316
ABSTRACTCarbon fiber reinforced thermoplastic (CFRTP) has a good electromagnetic shielding property due to its higher conductivity and broad absorption frequency bandwidth while presenting high specific strength and stiffness, their easy process-ability, cost-effectiveness, and recyclability. In the present study, laminated CFRTP made of carbon fiber-polyamide 6 unidirectional tape (UD tape) were fabricated with different laminate configurations and arrangements (unidirectional, bidirectional, and quasi–isotropic) and then were compared with randomly chopped-tape CFRTP. Thereafter, estimated electromagnetic interference shielding effectiveness (EMI-SE) using Simon formalism and flexural properties of CFRTP were evaluated. The result showed a remarkable total EMI-SE of 31–44 dB in the Ultra High Frequency (UHF) range and strongly correlated with the laminate configuration of CFRTP. Whereas, randomly chopped-tape CFRTP has a lower total EMI-SE of 23–27 dB in the same frequency range. In addition, the flexural test result showed the flexural strength and modulus are strongly influenced by the tape layer configuration in the laminated CFRTP. Moreover, microscopy analysis was also conducted to verify the interlaminar structure and fiber-to-fiber contact in the composite. In conclusion, laminated CFRTP made of UD tape can be considered as electromagnetic interference shielding material for both functional and structural applications. 相似文献