著者

Takuma Noda Hanseul Kim Kenta Watanabe Kota Suzuki Naoki Matsui Ryoji Kanno Masaaki Hirayama

出版者

The Ceramic Society of Japan

雑誌

Journal of the Ceramic Society of Japan (ISSN:18820743)

巻号頁・発行日

vol.131, no.10, pp.651-658, 2023-10-01 (Released:2023-10-01)

参考文献数

27

---

The reaction distribution in the composite cathode of an all-solid-state battery (ASSB) was directly tracked by in situ scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy (EDX). Contact between an electrode active material and a solid electrolyte is important for improving the properties of ASSBs as a promising next-generation battery. An in situ analysis is significant for establishing strategies to obtain sufficient contact areas between the active material and solid electrolyte particles. SEM-EDX has the advantages of in-situ measurement in spatial/time resolution, non-destruction, and versatility. We investigated the sensitivity of EDX to the Na signal and distinguishable distance to ensure sufficient spatial/time resolution. The acceleration voltage of 5 kV for the electron beam provided the highest sensitivity to the Na signal among all acceleration voltages. The distinguishable distance decreased with increasing magnification owing to the decrease in pixel size. Cross-sectional SEM-EDX images of the TiS2–Na3PS4/Na3PS4/Na–Sn cell were collected during charge/discharge. The time variation of Na signal intensity confirms the deintercalation of Na+ in the TiS2–Na3PS4 cathode layer. Moreover, intercalation on the solid electrolyte side proceeded faster than that on the current collector side. This was because the rate-determining step was ionic conductivity rather than electronic conductivity based on the difference between ionic and electronic conductivities. Ex situ observations detected only a uniform distribution in the composite after Na+ diffusion had relaxed. Operando SEM-EDX is a new tool to directly explore the intermediate conditions of electrode materials under ASSB operation.

著者

Kenta Watanabe Chihiro Oda-Yamamizo Kimiyo Sage-Ono Akemi Ohmiya Michiyuki Ono

出版者

Japanese Society for Plant Biotechnology

雑誌

Plant Biotechnology (ISSN:13424580)

巻号頁・発行日

vol.34, no.4, pp.177-185, 2018-01-25 (Released:2018-01-27)

参考文献数

53

被引用文献数

8 7

---

Japanese morning glory, Ipomoea nil, has several coloured flowers except yellow, because it can accumulate only trace amounts of carotenoids in the petal. To make the petal yellow with carotenoids, we introduced five carotenogenic genes (geranylgeranyl pyrophosphate synthase, phytoene synthase, lycopene β-cyclase and β-ring hydroxylase from Ipomoea obscura var. lutea and bacterial phytoene desaturase from Pantoea ananatis) to white-flowered I. nil cv. AK77 with a petal-specific promoter by Rhizobium (Agrobacterium)-mediated transformation method. We succeeded to produce transgenic plants overexpressing carotenogenic genes. In the petal of the transgenic plants, mRNA levels of the carotenogenic genes were 10 to 1,000 times higher than those of non-transgenic control. The petal colour did not change visually; however, carotenoid concentration in the petal was increased up to about ten-fold relative to non-transgenic control. Moreover, the components of carotenoids in the petal were diversified, in particular, several β-carotene derivatives, such as zeaxanthin and neoxanthin, were newly synthesized. This is the first report, to our knowledge, of changing the component and increasing the amount of carotenoid in petals that lack ability to biosynthesize carotenoids.

著者

Takumi Yabuzaki Miho Sato Hanseul Kim Kenta Watanabe Naoki Matsui Kota Suzuki Satoshi Hori Kazuhiro Hikima Satoshi Obokata Hiroyuki Muto Atsunori Matsuda Ryoji Kanno Masaaki Hirayama

出版者

The Ceramic Society of Japan

雑誌

Journal of the Ceramic Society of Japan (ISSN:18820743)

巻号頁・発行日

vol.131, no.10, pp.675-684, 2023-10-01 (Released:2023-10-01)

参考文献数

36

被引用文献数

1

---

Sulfide-type solid electrolytes for all-solid-state lithium-ion batteries are required to have high ionic conductivity, high (electro) chemical stability, and suitable mechanical properties. Compositing different materials is widely performed in developing multifunctional materials. However, only a few studies have investigated sulfide electrolytes due to the concern of lowering ionic conductivity. In this study, composite electrolytes comprising Li10GeP2S12 (LGPS)-type electrolytes and nanosized Al2O3 are fabricated by a solid-state reaction. Al2O3 particles are mainly located in the voids between LGPS particles, whereas very limited oxygen content is substituted for sulfur in the LGPS structure. LGPS–Al2O3 composites exhibit ionic conductivities of ∼5 mS cm−1 without significant changes by compositing Al2O3. LGPS–Al2O3 composites are softer and have higher atmospheric stability than uncomposed LGPS. All solid-state cells that use air-exposed LGPS–Al2O3 as a separator layer exhibit an improved cycle retention compared with that using air-exposed LGPS. These results demonstrate that electrolyte compositing is an effective means of improving other properties while maintaining high lithium ionic conductivity.

著者

Ryuichi Suwa Hironori Tajima Shinichi Gima Naoko Uehara Kenta Watanabe Shin Yabuta Jun Tominaga Yoshinobu Kawamitsu

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.OKD-069, (Released:2018-03-13)

被引用文献数

8

---

In Japan, several plant species have high commercial value because of their functional properties. In this study, we aimed to investigate the effects of soil type (red, dark-red, and gray soil) and growth stage (vegetative and reproductive) on the growth and polyphenol production (chlorogenic acid, rutin, hesperidin, and diosmin) of P. japonicum. Plants grown in gray soil had the heaviest dry weight, followed by those grown in dark-red soil. Flowering plants grown in gray soil had a polyphenol concentration lower than those grown in the other two soil types. However, differences in the concentration of polyphenols were even larger between the growth stages. During the flowering period, the concentration of polyphenols sharply increased in the stems. Additionally, the flowers contained relatively similar amounts of polyphenols to stems and leaves, accounting for approximately 1/4–1/2 of the net amount in the plant.