http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Yoshiyuki Sugahara (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
Pyrolytic Conversion of Blended Precursors into Ti-Al-N Ceramic Composites
Cheng, Fei,Sugahara, Yoshiyuki,Kuoda, Kazuyuki The Korean Ceramic Society 2000 The Korean journal of ceramics Vol.6 No.1
Pyrolytic preparations of Ti-Al-N ceramics from three blended precursors were investigated. The precursors were prepared stirring ($HA1N^{i}Pr_m$ and an aminolysis product of $Ti(NMe_2)_4$ with $MeHNCH_2CH_2$NHMe in $C_6/H_6$ . IR and $^1H\;NMR $analyses suggested that essentially no Ti-N-Al bonds were present in the precursors. Pyrolysis of the precursors under $NH_3-N_2$led to the formation of brown solids with ceramic yields of about 30%, and the Ti-Al ratios in the pyrolyzed products were close to those of the precursors. XRD analysis of the pyrolyzed product from the precursor with Ti:Al=5:1 indicated the formation of a NaCl-type compound as the only crystalline phase. Pyrolysis of the precursor with Ti:Al=2:1 led to the formation of AlN besides the major NaCl-type compound. A ceramic composite containing AlN and the NaCl-type compound was formed by pyrolysis of the precursor with Ti:Al=1:2.
-
Žunar Bojan,Ito Taiga,Mosrin Christine,Sugahara Yoshiyuki,Bénédetti Hélène,Guégan Régis,Vallée Béatrice 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00
Engineered living materials (ELMs) combine living cells with non-living scaffolds to obtain life-like characteristics, such as biosensing, growth, and self-repair. Some ELMs can be 3D-printed and are called bioinks, and their scaffolds are mostly hydrogel-based. One such scaffold is polymer Pluronic F127, a liquid at 4 °C but a biocompatible hydrogel at room temperature. In such thermally-reversible hydrogel, the microorganism-hydrogel interactions remain uncharacterized, making truly durable 3D-bioprinted ELMs elusive.We demonstrate the methodology to assess cell-scaffold interactions by characterizing intact alive yeast cells in cross-linked F127-based hydrogels, using genetically encoded ratiometric biosensors to measure intracellular ATP and cytosolic pH at a single-cell level through confocal imaging.When embedded in hydrogel, cells were ATP-rich, in exponential or stationary phase, and assembled into microcolonies, which sometimes merged into larger superstructures. The hydrogels supported (micro)aerobic conditions and induced a nutrient gradient that limited microcolony size. External compounds could diffuse at least 2.7 mm into the hydrogels, although for optimal yeast growth bioprinted structures should be thinner than 0.6 mm. Moreover, the hydrogels could carry whole-cell copper biosensors, shielding them from contaminations and providing them with nutrients.F127-based hydrogels are promising scaffolds for 3D-bioprinted ELMs, supporting a heterogeneous cell population primarily shaped by nutrient availability.
-
Single-crystalline tungsten oxide nanoplates
Deliang Chen,Hailong Wang,Rui Zhang,Lian Gao,Yoshiyuki Sugahara,Atsuo Yasumori 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.6
Tungsten oxide nanocrystals are important semiconductor materials with a suitable energy band gap (ca. 2.5 eV) for visible-light utilization. Though there are a great amount of reports on the synthesis of WO3 nanocrystals, no effective routes to two-dimensional (2D) WO3 nanocrystals have been reported. We here developed a novel and efficient route to synthesize free-standing single-crystalline WO3 nanoplates on a large scale and in a repeatable way. The proposed route involved a rational transformation of tungstatebased inorganic-organic hybrid nanobelts to single-crystalline WO3·H2O nanoplates, and then to single-crystalline monoclinic WO3 nanoplates with an inhibited crystal growth direction of [004]. The sizes of the as-obtained WO3 nanoplates are (200-500) nm × (200-500) nm × (10-30) nm. The WO3 nanoplates as-synthesized have high specific surface areas (up to 180m2 g−1) and showed remarkably enhanced visible-light photocatalytic properties in water splitting for O2 generation. Tungsten oxide nanocrystals are important semiconductor materials with a suitable energy band gap (ca. 2.5 eV) for visible-light utilization. Though there are a great amount of reports on the synthesis of WO3 nanocrystals, no effective routes to two-dimensional (2D) WO3 nanocrystals have been reported. We here developed a novel and efficient route to synthesize free-standing single-crystalline WO3 nanoplates on a large scale and in a repeatable way. The proposed route involved a rational transformation of tungstatebased inorganic-organic hybrid nanobelts to single-crystalline WO3·H2O nanoplates, and then to single-crystalline monoclinic WO3 nanoplates with an inhibited crystal growth direction of [004]. The sizes of the as-obtained WO3 nanoplates are (200-500) nm × (200-500) nm × (10-30) nm. The WO3 nanoplates as-synthesized have high specific surface areas (up to 180m2 g−1) and showed remarkably enhanced visible-light photocatalytic properties in water splitting for O2 generation.
-
Kaneti, Yusuf Valentino,Salunkhe, Rahul R.,Wulan Septiani, Ni Luh,Young, Christine,Jiang, Xuchuan,He, Yan-Bing,Kang, Yong-Mook,Sugahara, Yoshiyuki,Yamauchi, Yusuke The Royal Society of Chemistry 2018 Journal of materials chemistry. A, Materials for e Vol.6 No.14
<P>In this work, we propose a general template-free strategy for fabricating two-dimensional mesoporous mixed oxide nanosheets, such as metal cobaltites (MCo2O4, M = Ni, Zn) through the self-deconstruction/reconstruction of highly uniform Co-based metal glycerate nanospheres into 2D Co-based metal glycerate/hydroxide nanosheets, induced by the so-called “water treatment” process at room temperature followed by their calcination in air at 260 °C. The proposed ‘self-deconstruction/reconstruction’ strategy is highly advantageous as the resulting 2D metal cobaltite nanosheets possess very high surface areas (150-200 m<SUP>2</SUP>g<SUP>−1</SUP>) and mesoporous features with narrow pore size distribution. In addition, our proposed method also enables the crystallization temperature to achieve pure metal cobaltite phase from the precursor phase to be lowered by 50 °C. Using the 2D mesoporous NiCo2O4nanosheets as a representative sample, we found that they exhibit 6-20 times higher specific capacitance and greatly enhanced capacitance retention compared to the NiCo2O4nanospheres achieved through the direct calcination of the Ni-Co glycerate nanospheres. This highlights another advantage of the proposed strategy for enhancing the electrochemical performance of the mixed oxide products for supercapacitor applications. Furthermore, the asymmetric supercapacitor (ASC) assembled using the 2D NiCo2O4nanosheets//graphene oxide (GO) exhibits a maximum energy density of 38.53 W h kg<SUP>−1</SUP>, while also showing a high capacitance retention of 91% after 2000 cycles at 5 A g<SUP>−1</SUP>. It is expected that the proposed general method may be extended to other transition metal elements for creating 2D mixed oxide nanosheets with enhanced surface areas and improved electrochemical performance.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
