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991.
Kazumi Kato Desheng Fu Kiyotaka Tanaka Kazuyuki Suzuki Tatsuo Kimura Kaori Nishizawa Takeshi Miki 《International Journal of Applied Ceramic Technology》2005,2(1):64-72
We used a Ca–Bi–Ti complex alkoxide, in which metal–oxygen bonding was confirmed by spectroscopic analysis, to deposit CaBi4 Ti4 O15 (CBTi144) thin films in various configurations. The phase transition of non-ferroelectric pyrochlore to ferroelectric perovskite in the complex-alkoxy-derived CBTi144 thin films was found to depend on the Pt bottom electrodes. Matching of the atomic arrangement to the Ca–Bi–Ti–O thin films was predominant rather than the strain and crystallinity of the bottom electrode. The thin films crystallized at 650°C on (111)-oriented Pt showed random orientation and ferroelectric P – V hysteresis loops. The endurance property was excellent against a number of switchings. For this reason, CBTi144 thin films would be expected to be excellent for application to ferroelectric random access memories (FeRAM). Polar-axis-oriented CBTi144 films were fabricated on Pt foils using the complex metal alkoxide solution. The 500-nm-thick film had a columnar structure comprising well-developed grains. The a / b -axis orientation of the ferroelectric films is considered to be associated with the preferred orientation of Pt foil. The film showed improved ferro- and piezoelectric properties. The P r , E c , and d 33 values were enhanced to become twice those of CBTi144 thin films with random orientation. These polar-axis-oriented CBTi144 films are eminently useful in devices as Pb-free piezoelectric materials. 相似文献
992.
Syndiotactic polystyrene (s-PS) was blended with poly(ethylene glycol) (PEG) in 1,2-dichloroethane (DCE) solvent. The mixture became a homogeneous solution at 155 °C depending on the composition ratio of PEG to DCE. When the solution was cooled at the rate of 5 °C/min to room temperature, a thermoreversible gelation was occurred. Wide angle X-ray diffraction (WAXD) measurements revealed that the polymer chain of s-PS in the obtained gel was crystallized with a helical conformation, while that in the non-gelated sample was done with an all-trans planar zigzag conformation.After drying gelated samples at 70 °C for 24 h, a novel polymer blend type of the physical gel consisting of s-PS and PEG was obtained. Dynamic mechanical analysis (DMA) revealed that the physical gel had a high modulus and a long elastic plateau in the temperature range of −80-270 °C. 相似文献
993.
BiVO4 with a 2.3 eV band gap showed an activity for O2 evolution from aqueous solutions containing Ag+ as an electron scavenger under visible light irradiation (λ > 520 nm). The quantum yield was 0.5% at 450 nm.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
Ryunosuke Kato Teruyuki Komatsu 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(1):167-171
We report structure and photocatalytic activity of solid nanotubes comprising iron oxide (hematite, α-Fe2O3) nanoparticles. The initial precursor cylinders were prepared by alternating layer-by-layer assembly of poly-l-arginine (PLA) and iron-storage protein ferritin in a track-etched polycarbonate membrane (pore diameter: 400 nm) with subsequent dissolution of the template. The obtained (PLA/ferritin)3 nanotubes (outer diameter: 410 ± 14 nm) were calcinated at 500 or 700 °C under air, yielding iron oxide nanotubes. After the calcination, the cylindrical hollow structure completely remained, but its diameter, wall thickness, and maximum length were significantly diminished. SEM measurements revealed that the nanotubes prepared at 500 °C consist of uniform hematite nanoparticles with ca. 5 nm diameter and the nanotubes calcinated at 700 °C are composed of ca. 20 nm hematite nanoparticles. These nanotubes showed efficient photocatalytic activity for degradation of 4-chlorophenol; higher catalytic activity was observed in the reaction with 5 nm hematite nanoparticle nanotubes. 相似文献
995.
Nobuhito Katayama Hirohito Kato Yoichiro Taguchi Akio Tanaka Makoto Umeda 《International journal of molecular sciences》2014,15(8):14026-14043
Enamel matrix derivative (EMD) is widely used in periodontal tissue regeneration therapy. However, because the bioactivity of EMD varies from batch to batch, and the use of a synthetic peptide could avoid use from an animal source, a completely synthetic peptide (SP) containing the active component of EMD would be useful. In this study an oligopeptide synthesized derived from EMD was evaluated for whether it contributes to periodontal tissue regeneration. We investigated the effects of the SP on cell proliferation and osteoblast differentiation of human mesenchymal stem cells (MSCs), which are involved in tissue regeneration. MSCs were treated with SP (0 to 1000 ng/mL), to determine the optimal concentration. We examined the effects of SP on cell proliferation and osteoblastic differentiation indicators such as alkaline phosphatase activity, the production of procollagen type 1 C-peptide and osteocalcin, and on mineralization. Additionally, we investigated the role of extracellular signal-related kinases (ERK) in cell proliferation and osteoblastic differentiation induced by SP. Our results suggest that SP promotes these processes in human MSCs, and that ERK inhibitors suppress these effects. In conclusion, SP promotes cell proliferation and osteoblastic differentiation of human MSCs, probably through the ERK pathway. 相似文献
996.
D. Takeuchi M. Ogura S.-G. Ri H. Kato H. Okushi S. Yamasaki 《Diamond and Related Materials》2008,17(6):986-988
By total photoelectron yield spectroscopy (TPYS), we have found a thermal instability of a negative electron affinity in hydrogen-terminated n-type diamond films, which has never been observed for intrinsic and p-type diamond films. Experimentally, we have succeeded in detecting surface defect states and surface valence band extended states on the same n-type sample after soft annealing from 100 to 300 °C, which allowed us to evaluate the surface Fermi level and surface band bending using phosphorus doping parameters. Our results show that “quasi-positive” electron affinity prevents electron emission from an n-type diamond film even though its surface has a negative electron affinity. 相似文献
997.
Masaki Kato Haruhiko Ogata Hidetoshi Tahara Akira Shimamoto Yoshiteru Takekita Yosuke Koshikawa Keiichiro Nishida Shinpei Nonen Koichiro Higasa Toshihiko Kinoshita 《International journal of molecular sciences》2022,23(7)
Major depressive disorder (MDD) is a life-impairing disorder, and early successful treatment is important for a favorable prognosis. However, early response to antidepressants differs widely among individuals, and is difficult to predict pre-treatment. As miRNAs have been reported to play important roles in depression, identification of miRNAs associated with antidepressant treatment responses and their interacting genes and pathways will be beneficial in understanding the predictors and molecular mechanisms of depression treatment. This randomized control trial examined miRNAs correlated with the early therapeutic effect of selective serotonin reuptake inhibitors (SSRIs; paroxetine or sertraline) and mirtazapine monotherapy. Before medication, we comprehensively analyzed the miRNA expression of 92 depressed participants and identified genes and pathways interacting with miRNAs. A total of 228 miRNAs were significantly correlated with depressive symptoms improvements after 2 weeks of SSRIs treatment, with miR-483.5p showing the most robust correlation. These miRNAs are involved in 21 pathways, including TGF-β, glutamatergic synapse, long-term depression, and the mitogen-activated protein kinase (MAPK) signaling pathways. Using these miRNAs enabled us to predict SSRI response at week 2 with a 57% difference. This study shows that pre-treatment levels of miRNAs could be used to predict early responses to antidepressant administration, a knowledge of genes, and an identification of genes and pathways associated with the antidepressant response. 相似文献
998.
The behavior of solid particles suspended in the freeboard of a 12 cm i.d. fluidized bed was studied using FCC particles of which the weight-mean diameter was 65 – 68 μm. The height of the freeboard was 180 cm, and the superficial gas velocity was changed from 15 to 50 cm s?1.The weight-mean diameter and holdup of solid particles in the freeboard below the TDH vary with the axial position and the gas velocity. The lateral distribution of the solids holdup measured by a capacitance probe is almost flat in the region of r ? 5 cm, but the relative pulse frequency detected by a fiber optic probe indicates that the solids holdup increases greatly in the immediate vicinity of the column wall. The flow patterns of solid particles were measured by a fiber optic probe and a thermal response probe. The steady internal circulation of solid particles is formed in the freeboard below the TDH, and the circulating solids flow rate is much larger than the net entrainment rate of solid particles. 相似文献
999.
We had already made a report on outcome of schizophrenia (1986). The patients, 129 typical schizophrenia, were continuously observed over 30 years in the Kawagoe Dojinkai Hospital. Recently, we again evaluated their prognoses according to the same criteria as adopted in the first report, and divided them into the following five groups. [symbol: see text]: completely remitted group (21 persons, 16.3%), [symbol: see text]: almost remitted cases now holding jobs (23 persons, 17.8%), [symbol: see text]: Slightly remitted group showing good adjustment at home or hospital (41 persons, 31.8%), [symbol: see text]: maladjusted cases always showing an unfavorable condition (25 persons, 19.4%), x : incurable cases (19 persons, 14.7%). 1) In the last 8 years, there were 30 persons (23.3% of the whole patients) who showed prognostic changes (10 persons improved, 20 persons worsen). While the second group ([symbol: see text]) has seen fewer persons (12 persons down) than previous study, the third group ([symbol: see text]) has seen more persons (9 persons up). Each three groups, that is, the first two groups ([symbol: see text] + [symbol: see text], 44 persons, 34.1%), the third group ([symbol: see text], 41 persons, 31.8%), and the forth and fifth groups ([symbol: see text] + x, 44 persons, 34.1%) accounted for a third of the whole patients. It is after 32 years on the average (extending from 21 to 50 years) from the onset of illness that they showed prognostic changes. 2) Generally speaking, catatonic patients had favorable prognoses, hebephrenic patients unfavorable ones, and paranoid patients medium ones. But 4 improved persons in the forth and fifth groups were all hebephrenic type. 3) 17 among the 30 persons who showed prognostic changes were unstable type. They took a wave-like course. 4) 27 of all the 129 patients were dead. 25 were dead from disease mentioned below. Malignancy (8 persons), Cerebral vascular disease, Pneumonia and Diabetes (3 persons), Heart-failure (2 persons), Ileus, Myocardial infarction, Hepato-cirrhosis, Gastric ulcer, Tuberculosis and Natural death (1 person). 2 persons committed suicide. 5) Outcome of 45 patients who discontinued our medical therapy became clear as follows. [symbol: see text] + [symbol: see text]: 18 persons (40.0%), [symbol: see text]: 9 persons (20.0%), [symbol: see text] + x : 18 persons (40.0%). A smaller percentage of the patients belongs to the third group ([symbol: see text]) than that of our patients who were continuously followed by us. 相似文献
1000.
Shota Saga Hidetoshi MatsumotoKeiichiro Saito Mie MinagawaAkihiko Tanioka 《Journal of power sources》2008
In the present study, composite polyelectrolyte membranes were prepared from sulfonated polystyrene and fullerene. The additive effect of the fullerene on the membrane properties – electric resistance, mechanical strength, oxidation resistance, and methanol permeability – were measured. The addition of fullerene improved the oxidation resistance, and reduced the methanol crossover. The mechanical strength of the fullerene-composite membrane, on the other hand, was not improved. The direct methanol fuel cell (DMFC) based on a 1.4 wt% fullerene-composite membrane showed the highest power density of 47 mW cm−2 at the current density of 200 mA cm−2 (this value is 60% of the Nafion-based DMFC). The transmission electron microscopy (TEM) observations suggest that the improved dispersity of the fullerene and the reduced number of micropores in the membranes would improve its performance in the fuel cell. 相似文献