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61.
Hiroshi Nakatsuji Yoshinari Kamakura Kenji Taniguchi 《Journal of Computational Electronics》2003,2(2-4):109-112
Transport properties of the two-dimensional hole gas in inversion layer of strained Si/SiGe p-MOSFETs are investigated using the full-band Monte Carlo simulator based on the nonlocal pseudopotential calculation. The hole mobility is significantly enhanced by the strain in the case of Ge content of ≥20%. Moreover, we also present the high-field transport characteristics of 2D holes. In contrast to the low-field mobility, the hole saturation velocity does not significantly enhanced by the strain. 相似文献
62.
Hohkawa K Suda T Aoki Y Hong C Kaneshiro C Koh K 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2002,49(4):466-474
This paper presents results of a design study on a semiconductor coupled surface acoustic wave (SAW) convolver in which bi-directionally propagating SAWs, on a piezoelectric substrate with a high coupling coefficient, couple with bonded semiconductor diodes through multistrips. To obtain convolution signals with a high efficiency, we adopted a diode-balanced bridge structure for the nonlinear operation. We also found that the tapping pitches of the multi-strip electrodes have robustness against operation frequency variation and temperature-dependent variation on the delay of the SAW. We verified the effectiveness of the device in. a circuit simulation and an experiment on a test circuit, which was fabricated by using an epitaxial lift-off film-bonding process. 相似文献
63.
Michio Yamada Konomi Tokutomi Ayaka Takehara Yusuke Sakai Yutaka Maeda Tadashi Hasegawa 《Fullerenes, Nanotubes and Carbon Nanostructures》2014,22(1-3):66-74
Tröger's base (TB, 1) and its analogues were synthesized and were subject to the titration experiments to evaluate their ability of supramolecular complexation with C60. Results demonstrate clearly that the fluorene-based TB analogue (2) and the bioctylfluorene-based TB analogue (3) show 1:1 binding with C60 to form the corresponding complexes while TB 1 does not. Titration experiments exhibited that the association constant (Kass) of 3/C60 (48.1 ± 7.9 M ?1) was larger than that of 2/C60 (13.7 ± 1.4 M ?1). The formation of the 1:1 binding complexes 2/C60 and 3/C60 was also confirmed by MALDI-TOF mass spectrometry. Theoretical calculations suggest that 2 and 3 have appropriate cavities to embrace C60. These findings indicate that not only the π/π interaction between the fluorene moieties and the C60 surface but also the CH/π interaction between the octyl groups and the C60 surface serve efficiently in the supramolecular complexation with C60. 相似文献
64.
Soshu Kirihara Yusuke Itakura Satoko Tasaki 《International Journal of Applied Ceramic Technology》2013,10(3):468-473
Titania micropatterns with periodic arrangements were successfully formed on glass substrates for use with electromagnetic wave energy resonance and localizations in terahertz frequency ranges. Geometric arrangements of acrylic polygonal tablets with titania particle dispersions were fabricated by using micropatterning stereolithography. Moreover, periodically arranged full anatase‐phase titania tablets were created homogeneously through liquid‐phase crystal depositions of water solvent processes, using microtemplates fabricated by using the stereolithography system. The terahertz wave properties were measured and calculated by using a time‐domain spectroscopic system and finite‐difference time‐domain method. 相似文献
65.
Shinichi Kitade Kazuo Asuka Isamu Akiba Yusuke Sanada Kazuo Sakurai Hiroyasu Masunaga 《Polymer》2013,54(1):246-257
Shear-induced crystallization of a long chain hyper-branched polypropylene (LCB-PP, denoted PP-3) was carried out at a relatively high temperature of 170 °C, close to its melting temperature of 158 °C. Small-angle X-ray scattering (SAXS) showed that the intensity ratio of the normal to the perpendicular to the shear (V/H) was always larger than 1 for PP-3, indicating that shish-like structures were predominately formed and further growth to kebab was suppressed in PP-3. The crystallization behavior of PP-3 can be explained by the nature of PP-3 that there were a large amount of crystallization nuclei due to their branching points, and the point-like precursors formed from these nuclei were arrayed linearly along the shear direction and transformed into thread-like precursors or premature shishs; however, owing to the large amount of branching, further progress in crystallization was suppressed. 相似文献
66.
Kenji Imai Koji Takai Tatsunori Hanai Makoto Shiraki Yusuke Suzuki Hideki Hayashi Takafumi Naiki Youichi Nishigaki Eiichi Tomita Masahito Shimizu Hisataka Moriwaki 《International journal of molecular sciences》2014,15(7):11294-11306
Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis. 相似文献
67.
Dr. Tomoya Hirano Dr. Takashi Fujiwara Dr. Hideaki Niwa Michitake Hirano Kasumi Ohira Yusuke Okazaki Shin Sato Dr. Takashi Umehara Dr. Yuki Maemoto Prof. Akihiro Ito Prof. Minoru Yoshida Prof. Hiroyuki Kagechika 《ChemMedChem》2018,13(15):1530-1540
The histone methyltransferase SET7/9 methylates not only histone but also non‐histone proteins as substrates, and therefore, SET7/9 inhibitors are considered candidates for the treatment of diseases. Previously, our group identified cyproheptadine, used clinically as a serotonin receptor antagonist and histamine receptor (H1) antagonist, as a novel scaffold of the SET7/9 inhibitor. In this work, we focused on dibenzosuberene as a substructure of cyproheptadine and synthesized derivatives with various functional groups. Among them, the compound bearing a 2‐hydroxy group showed the most potent activity. On the other hand, a 3‐hydroxy group or another hydrophilic functional group such as acetamide decreased the activity. Structural analysis clarified a rationale for the improved potency only by tightly restricted location and type of the hydrophilic group. In addition, a SET7/9 loop, which was only partially visible in the complex with cyproheptadine, became more clearly visible in the complex with 2‐hydroxycyproheptadine. These results are expected to be helpful for further structure‐based development of SET7/9 inhibitors. 相似文献
68.
Yuichi Nakahara Mai Furusawa Yuta Endo Toshiya Shimazaki Keita Ohtsuka Yusuke Takahashi Yiyuan Jiang Aiichiro Nagaki 《化学工程与技术》2019,42(10):2154-2163
A continuous‐flow reaction system was developed, allowing flow conditions of the entire system to be maintained at a predetermined constant level, which is one of the most significant factors for successful industrial application. Controlled/living anionic polymerization was selected as a model reaction since the characteristics of its polymer products, molecular weights, and molecular weight distributions are highly susceptible to changes in the relative flow rates of a monomer and initiator solutions. In flow microreactors, controlled/living anionic polymerization of styrene in tetrahydrofuran (THF)/hexane initiated by THF‐diluted n‐butyllithium (n‐BuLi) was examined. Poly(styrenes) of larger molecule sizes such as Mn > 15 000 were successfully synthesized. After continuous operation for four hours, ca. 0.5 kg of the polymer was readily produced with narrow molecular weight distribution, demonstrating the applicability of this continuous‐flow system for controlled/living anionic polymerization on considerably large scale with a view to its industrial usage in the future. 相似文献
69.
Aiichiro Nagaki Yiyuan Jiang Hiroki Yamashita Naoshi Takabayashi Yusuke Takahashi Jun-ichi Yoshida 《化学工程与技术》2019,42(10):2113-2118
The lithiation of 5,5′‐dibromo‐2,2′‐bithiophene with one equivalent of an alkyllithium such as n‐BuLi or s‐BuLi was studied by varying the residence time in flow microreactors. With a short residence time, the product 2,2′‐bithiophene (3) derived from dilithiation was obtained preferentially and a significant amount of the starting material 5,5′‐dibromo‐2,2′‐bithiophene remained unchanged. An increase in the residence time caused a higher yield of the product 5‐bromo‐2,2′‐bithiophene derived from monolithiation with expense in the yields of 2,2′‐bithiophene and 5,5′‐dibromo‐2,2′‐bithiophene. The lithiation using MeLi gave the product 5‐bromo‐2,2′‐bithiophene preferentially even with a very short residence time. 相似文献
70.
Xiao-Dong Zhang Wen-Lu Zhang Ze-Xing Cai Yuan-Kai Li Yusuke Yamauchi Xin Guo 《Ceramics International》2019,45(5):5240-5248
LaFeO3 micro-spindles with intriguing structural characteristics were synthesized using cyano-bridged coordination polymers as sacrificial templates. Within a longitudinal dimension of less than 5?µm, each micro-spindle features a hollow center contained in a mesoporous shell with hexagonal cross section. Conductometric gas sensors developed from these micro-spindles demonstrate a comprehensively improved NO2-sensing performance over other-reported LaFeO3 devices, including lower operating temperature (155?°C), higher sensitivity (response of 81.4% under 5?ppm) and expedited response and recovery (40?s/329?s). Such performance is enabled by a semiconducting mechanism governed by the formation and catalytic dissociation of nitrite species during NO2 adsorption on LaFeO3, facilitated by the special hierarchical structure of the micro-spindle. 相似文献