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Carbon Resources Conversion 2023年第3期6卷 205-214页

作者： Kenta Dejima Hirokazu Ishitobi He Gao Mai saito Nobuyoshi Nakagawa Graduate School of Science and Technology Gunma University1-5-1Tenjin-choKiryuGunma 376-8515Japan Division of Environmental Engineering Science Gunma University1-5-1Tenjin-choKiryuGunma 376-8515Japan Faculty of Science and Technology Gunma University1-5-1Tenjin-choKiryuGunma 376-8515Japan

The method to increase PtRu utilization and its catalytic activity of PtRu nanoparticles supported on reduced graphene oxide(RGO)by avoiding its restacking was proposed with the aim of developing an active catalyst for a direct methanol fuel *** heat treatment at 200◦C of the GO aerogel(GOA)prepared by freeze drying of GO ice was introduced to weaken the attractive force of the hydrogen bonding between the GO sheets followed by the composite with the nanoparticles,i.e.,ketjenblack(KB),TiO_(2)and Ti_(4)O_(7),at different weight *** catalyst supported on the heat-treated GOA(RGOA),PtRu/RGOA,improved the PtRu utilization to some extent and also increased the ECSA and mass activity compared to that of PtRu/*** had fewer oxygen functional groups,especially the epoxy *** to the treatment and composite,the PtRu utilization was increased from 66.5%for PtRu/RGO to 128.6%for PtRu/RGOA+Ti_(4)O_(7)(4:1)and the mass activity was improved from 50.7 A/g-PtRu for PtRu/RGO to 130.5 A/g-PtRu for PtRu/RGOA+Ti_(4)O_(7)(1:1).The Ti_(4)O_(7)nanoparticles showed the best catalytic performance for the composite suggesting that the strong interaction between Ti_(4)O_(7)and the Pt nanoparticles was effective due to its high electronic conductivity.

关键词： Reduced graphene oxide Restacking Catalyst utilization Mass activity Composite catalyst Methanol oxidation Ti4O7

Combustion synthesis of YAG:Ce phosphors via the thermite reaction of aluminum

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Journal of Rare Earths 2018年第3期36卷 248-256页

作者： Junpei Ohyama Chunyu Zhu Genki saito Miki Haga Takahiro Nomura Norihito Sakaguchi Tomohiro Akiyama Center for Advanced Research of Energy and Materials Hokkaido UniversityKita 13 Nishi 8KitakuSapporo 060-8628Japan Division of Applied Chemistry&Frontier Chemistry Center Faculty of EngineeringHokkaido University5apporoHokkaido 060-8628Japan Graduate School of Chemical Sciences and Engineering Hokkaido University SapporoHokkaido 060-8628Japan

Cerium-doped yttrium aluminum garnet（YAG：Ce） as a yellow phosphor for white light-emitting diodes（LEDs） was synthesized via a facile combustion method using Y2 O3, CeO2, Al2 O3, Al,and NaClO4 as raw materials. The combustion synthesis approach utilizes the strong exothermic oxidation of aluminum to realize a self-sustaining reaction. In this study, we investigated the effects of the ratios of Al2 O3 to AI,fluxes, and coprecipitated materials as raw materials on the luminescence properties of the synthesized YAG：Ce phosphors. When the amount of Al2 O3 x is varied, the combustion reaction proceeds at x ≤ 1.8,with x = 1.725 being the optimum condition for producing a high-performance product. When 5 wt%BaF2 is added, the luminescence intensity is significantly improved owing to a decrease of YAP（YAlO3）formation with improved uniformity. However, the addition of CaF2 and NaF does not improve the luminescence properties. To suppress the segregation of CeO2, we used the coprecipitated material Y2 O3-CeO2 as a raw material. Unlike with separate addition of Y2 O3 and CeO2, Ce ions are uniformly distributed in the coprecipitated material, resulting in improved luminescence properties. The combination of BaF2 and coprecipitated material significantly improves the internal quantum efficiency to83.0%, which is close to that of commercial phosphors.

关键词： Phosphor Yttrium aluminum garnet Combustion synthesis Flux Coprecipitated material Rare earths

Effectiveness of narrow-band imaging magnification for invasion depth in early colorectal cancer

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World Journal of Gastroenterology 2010年第14期16卷 1727-1734页

作者： Masakatsu Fukuzawa Yutaka saito Takahisa Matsuda Toshio Uraoka Takao Itoi Fuminori Moriyasu Division of Endoscopy National Cancer Center Hospital Tokyo 1040045 Japan Division of Gastroenterology and Hepatology Tokyo Medical University Tokyo 1600023 Japan Department of Endoscopy Okayama University Hospital Okayama 7008558 Japan Microvasculature

AIM: To evaluate the surface microvascular patterns of early colorectal cancer (ECC) using narrow-band imaging (NBI) with magnification and its effectiveness for invasion depth diagnosis. METHODS: We studied 112 ECC lesions [mucosal/ submucosal superficial (m/sm-s), 69; sm-deep (sm-d), 43] ≥ 10 mm that subsequently underwent endoscopic or surgical treatment at our hospital. We compared microvascular architecture revealed by NBI with magnification to histological findings and then to magnifi- cation colonoscopy pit pattern diagnosis. RESULTS: Univariate analysis indicated vessel density: non-dense (P < 0.0001); vessel regularity: negative (P < 0.0001); caliber regularity: negative (P < 0.0001); vessel length: short (P < 0.0001); and vessel meandering: positive (P = 0.002) occurred significantly more often with sm-d invasion than m/sm-s invasion. Multivariate analysis showed sm-d invasion was independently associated with vessel density: non-dense[odds ratio (OR) = 402.5, 95% confidence interval (CI): 12.4-13 133.1] and vessel regularity: negative (OR = 15.9, 95% CI: 1.2-219.1). Both of these findings when combined were an indicator of sm-d invasion with sensitivity, specificity and accuracy of 81.4%, 100% and 92.9%, respectively. Pit pattern diagnosis sensitivity, specificity and accuracy, meanwhile, were 86.0%, 98.6% and 93.8%, respectively, thus, the NBI with magnification findings of non-dense vessel density and negative vessel regularity when combined together were comparable to pit pattern diagnosis. CONCLUSION: Non-dense vessel density and/or negative vessel regularity observed by NBI with magnification could be indicators of ECC sm-d invasion.

关键词： Colorectal neoplasms Narrow-band imaging Microvasculature

Genetic relationships among sympatric varieties of Acer mono in the Chichibu Mountains and Central Hokkaido, Japan

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Journal of Forestry Research 2017年第4期28卷 699-704页

作者： Chunping Liu Jian Cong Hailong Shen Cunxue Lin Yoko saito Yuji Ide State Key Laboratory of Forest Genetics and Breeding Northeast Forestry UniversityHarbin 150040China Foreign Capital Project Office Forestry Department of Liaoning ProvinceShenyang 110036China Mudanjiang Branch of Heilongjiang Academy of Agricultural Sciences Mudianjiang 157041China Laboratory of Forest Ecosystem Studies Department of Ecosystem StudiesGraduate School of Agriculture and Life ScienceThe University of TokyoYayoi 1-1-1Bunkyo-kuTokyo 113-8657Japan

Acer mono Maxim. is one of the major components of cool temperate forests in Japan. Some of its many varieties are distributed sympatrically. Because of its great variability, the intraspecific taxonomy and nomenclature of the species are controversial. To understand the genetic relationships among these varieties and whether hybridization or introgression occurred among the sympatric varieties, we studied the genetic relationships among sympatric varieties of A. mono in the Chichibu Mountains (A. mono var. ambiguum, A. mono var. connivens, A. mono var. marmoratum) and Central Hokkaido (A. mono var. mayrii and A. mono var. glabrum) in Japan. Our results showed that varieties in Chichibu are genetically close, suggesting that hybridization or introgression might occur between these varieties, which could explain the higher genetic diversity of varieties in Chichibu than in Hokkaido. In contrast to the close relationships between the varieties in Chichibu, varieties in Hokkaido seemed relatively separated from each other; indeed, there may be reproductive isolation between the two varieties. The results provide new insight for the taxonomy of the varieties of A. mono, especially the sympatric varieties, in Japan.

关键词： Genetic differentiation Hybridization Introgression Maple nSSR

Operational efficiencies and costs of an arm roll forwarder: A case study at Nasu in Tochigi Prefecture, Japan

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Journal of Forestry Research 2013年第3期24卷 577-583页

作者： Kazuhiro Aruga Yuto Otsuka Chikara Nakahata Reiko Yamaguchi Masashi saito Mayu Nagasaki Department of Forest Science Faculty of Agriculture Utsunomiya University350 Mine Utsunomiya 321-8505 Japan Frontier Agriscience and Technology Center Faculty of Agriculture Shinshu UniversityNagano 399-4598 Japan Japan Wood Energy Co. Ltd.Tokyo 198-0036

We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a container. Such a forwarder can shorten the loading and untoading times and improve operational efficiency. We examined two operation systems with an arm roll forwarder and a forwarder. In the first system the loading was done with a grapple-loader. In the second system the loading was done with a processor. The loading times of an arm roll forwarder were significantly tess than those of a forwarder. Because the optimal cycle times （excluding the waiting times for an arm roll for- warder） were significantly reduced, the costs of using an arm roll for- warder are lower, although the loading capacity was small and the hourly operation cost was high. The maximum operational efficiencies varied depending on forwarding distances. The second operation system with an arm roll forwarder exhibited the best operational efficiency within a 1,580-m forwarding distance, and beyond that distance it exhibited the highest operational efficiency when a forwarder was used. Similarly, the cost of operation of the system with an arm roll forwarder was the lowest within a 1,130-m forwarding distance, and beyond that distance the cost was the lowest when using the forwarder. Therefore, the arm roll for- warder is effective within a certain forwarding distance.

关键词： arm roll forwarder steel container operational efficiency cost forwarding distance

Evidence for structural phase transitions and large effective band gaps in quasi-metallic ultra-clean suspended carbon nanotubes

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Nano Research 2013年第10期6卷 736-744页

作者： Shun-Wen Chang Rohan Dhall Moh Amer Kentaro Sato Riichiro saito Stephen Cronin Department of Physics and Astronomy University of Southern California Los Angeles CA 90089 USA Department of Electrical Engineering University of Southern California Los Angeles CA 90089 USA Department of Chemistry University of Southern California Los Angeles CA 90089 USA Department of Physics Tohoku University Sendai 980-8578 Japan

We report evidence for a structural phase transition in individual suspended metallic carbon nanotubes by examining their Raman spectra and electron trans- port under electrostatic gate potentials. The current-gate voltage characteristics reveal anomalously large quasi-metallic band gaps as high as 240 meV, the largest reported to date. For nanotubes with band gaps larger than 200 meV, we observe a pronounced M-shape profile in the gate dependence of the 2D band （or G＇ band） Raman frequency. The pronounced dip （or softening） of the phonon mode near zero gate voltage can be attributed to a structural phase transition （SPT） that occurs at the charge neutrality point （CNP）. The 2D band Raman intensity also changes abruptly near the CNP, providing further evidence for a change in the lattice symmetry and a possible SPT. Pronounced non-adiabatic effects are observed in the gate dependence of the G band Raman mode, however, this behavior deviates from non-adiabatic theory near the CNP. For nanotubes with band gaps larger than 200 meV, non-adiabatic effects should be largely suppressed, which is not observed experimentally. This data suggests that these large effective band gaps are primarily caused by a SPT to an insulating state, which causes the large modulation observed in the conductance around the CNP. Possible mechanisms for this SPT are discussed, including electron-electron （e.g., Mott） and electron-phonon （e.g., Peierls） driven transitions.

关键词： carbon nanotube Raman spectroscopy phase transition bandgap energy

Mechanochemical Synthesis of Visible-light Induced Photocatalyst with Nitrogen and Carbon Doping

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过程工程学报 2006年第3期6卷 477-481页

作者：殷澍 Maskazu Komatsu 张其武李锐星唐清 Fumio saito Tsugio Sato Inst. Multidisciplinary Research for Advanced Materials Tohoku Univ.2-1-1KatahiraAoba-kuSendaiMiyagi 980-8577Japan

Nitrogen and/or carbon doped titania photocatalysts were prepared by a novel mechanochemical method. The prepared powders possessed two absorption edges around 400 and 540 nm wavelengths and showed excellent photocatalytic ability for nitrogen monoxide oxidation under visible light irradiation. Under the irradiation of visible light of wavelength >510 nm,37% of nitrogen monoxide could be continuously removed by the carbon and nitrogen co-doped titania prepared by planetary ball milling of P-25 titania–10% hexamethylenetetramine mixture followed by calcination in air at 400-C.

关键词： mechanochemical synthesis titania photocatalyst carbon and nitrogen doping nitrogen monoxide oxidation

Deformation mechanism at impact test of Al-11% Si alloy processed by equal-channel angular pressing with rotary die

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中国有色金属学会会刊：英文版 2007年第1期17卷 104-109页

作者：马爱斌 Y. NISHIDA 江静华 N. saito I. SHIGEMATSU A. WATAZU Department of Materials Science and Engineering Hohai University National Institute of Advanced Industrial Science and Technology ShimoshidamiMoriyama-ku

Al-11%Si(mass fraction)alloy was transformed into a ductile material by equal-channel angular pressing(ECAP)with a rotary *** mechanisms at impact test,slip deformation by dislocation motion and grain boundary sliding,were *** ultrafine grains with modified grain boundaries and the high content of fine particles(<1μm)were necessary for attaining high absorbed *** results contradict the condition of slip deformation by dislocation motion and coincide with that of grain boundary *** fine zigzag lines like a mosaic were observed on the side surface of the tested *** observed lines may show grain boundaries appeared by the sliding of grains.

关键词：铝合金变形行为微观结构晶界滑动

Evolving roles of magnifying endoscopy and endoscopic resection for neoplasia in inflammatory bowel diseases

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World Journal of Gastrointestinal Oncology 2022年第3期14卷 646-653页

作者： Shintaro Akiyama Taku Sakamoto Joshua M Steinberg Yutaka saito Kiichiro Tsuchiya Department of Gastroenterology University of TsukubaIbaraki 305-8575Japan Endoscopy Division National Cancer Center HospitalTokyo 104-0045Japan Department of Inflammatory Bowel Disease Gastroenterology of the RockiesDenverCO 80218United States

Magnifying endoscopy is a useful technique to differentiate neoplasia from non-neoplastic lesions. Data regarding the clinical utility of magnifying endoscopy for neoplasia in patients with inflammatory bowel disease(IBD) has been *** Kudo’s pit pattern types Ⅲ-Ⅴ are findings suggestive of neoplasia in non-IBD patients, these pit patterns are predictive of IBD-associated neoplasia as ***, active chronic inflammatory processes, particularly regenerative changes, can mimic neoplastic pit patterns and may affect a meticulous evaluation of pit pattern diagnosis in patients with IBD. The clinical evidence regarding the utility of magnifying endoscopy with narrow band imaging or endocytoscopy has also been evolving in regard to the diagnosis of IBD-associated neoplasia. These advanced endoscopic techniques are promising for multiple reasons;not only for making an accurate diagnosis of neoplasia, but also in determining if endoscopic resection is appropriate for such lesions in patients with IBD. In this review, we discuss the diagnostic accuracy and limitations of magnifying endoscopy in assessing IBD-associated neoplasia and examine the feasibility and outcomes of endoscopic resection for these lesions.

关键词： Magnifying endoscopy Neoplasia Ulcerative colitis Inflammatory bowel disease Endoscopic resection

Reconstructing sea surface temperature, sea surface salinity and partial pressure of carbon dioxide in atmosphere in the Okinawa Trough during the Holocene and their paleoclimatic implications

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Chinese Science Bulletin 2003年第B6期48卷 88-92页

作者： MENGXianwei LIUYanguang LlUZhenxia DUDewen HUANGQiyu Y.saito KeyLaboratoryofMarineSedimentologyandEnvironmentalGeology FirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China OceanUniversityofChina Qingdao266071China UniversityofTaiwan TaibeiChina GeologicalSurveyofJapan Tsukuba305-8567Japan

The sediment core DGKS9603 collected from the Okinawa Trough was used as research target. By use of unsaturated index U37^k of long-chain alkenone, δ^13C of POC and of planktonic foraminifera (G sacculifer), the evolutions of sea surface temperature and partial pressure of carbon dioxide in the atmosphere during the Holocene were reconstructed in the Okinawa Trough. And in combination of δ^18O of planktonic foraminifera, the relative difference of sea surface salinity during the Holocene was also ***, three cooling events (E1-E3) were identified,each of which occurred at 1.7-1.6, 5.1-4.8 and 8.1-7.4kaBP (cal), respectively. Of the three events, E2 and E3 are globally comparable, their occurrence mechanism would be that the main stream of the Kuroshio Current shifted eastward due to the enhanced circulation of the northeastern Pacific Ocean, which was driven in turn by amplified intensity of sunshine and subsequent enhancement of subtropical high pressure; E1 corresponds to the Small Ice-Age Event occurring between 1550 and 1850AD in China. In the Okinawa Trough, E1 might be also related to the eastward shift of main stream of the Kuroshio current driven by powerful Asia winter monsoon.

关键词：冲绳岛海槽全新世二氧化碳温度盐度日本海流亚热带高气压太平洋气候变化