著者

por Mateo y José María Puyol Lalaguna

出版者

Ricardo F. de Rojas

巻号頁・発行日

1911

著者

川端 猛夫 SOKEIRIK Y. S.- SOKEIRIK Y.S.

出版者

京都大学

雑誌

特別研究員奨励費

巻号頁・発行日

2010

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α位に分岐のない脂肪族アルデヒド間のクロスアルドール反応を目的とした触媒開発に取り組んだ。標的反応はアセトアルデヒドと3-アシルアミノプロピオンアルデヒド(RCONHCH_2CH_2CHO)とのクロスアルドール反応で、生成物は高脂血症治療薬リピトールの合成中間体となる。本触媒ではアルデヒドのエナミンへの活性化にプロリン骨格ではなく、ピペリジンを用いた。ピペリジンはプロリンのアミン部分であるピロリジンに比べて、生成するエナミンの反応性が低い。これにより反応性の高いアセトアルデヒドのみをドナーアルデヒドとして活性化できると期待した。一方、3-アシルアミノプロピオンアルデヒドのアクセプターとしての選択的活性化は、触媒分子のピペリジン4位に組み込んだアミノ基による基質のアミドNH基との水素結合形成を介して基質のホルミル基が反応点近傍に配置された触媒側鎖のカルボン酸によりプロトン化を受けることで達成したいと考えた。想定通り、3-アシルアミノプロピオンアルデヒドをアクセプターとし、アセトアルデヒドをドナーとするクロスアルドール反応が進行したが、過反応により脱水が起こり、アルドール縮合体が得られた。現在、脱水を起こさず、アルドール反応の段階に留めて制御する反応系を検討中である。また位置選択的ハロゲン化触媒の開発を目指し、スルフィド及びチオアミドを活性中心とする有機触媒を開発した。これらはオレフィン類のハロアミノ化の良好な触媒となることわかったが、位置選択性の獲得にはまだ至っていない。

著者

東藤 貢 高橋 清 JAR BenP.Y. BEGUELIN Philippe

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.65, no.631, pp.432-438, 1999-03-25

参考文献数

21

被引用文献数

1 1

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Toughening mechanisms of three types of rubber toughened poly (methyl methacrylate) (RT-PMMA) were investigated under mode I loading condition by optical and electron microscopies in conjunction with the quantitative evaluation of mode I fracture toughness. Polarized optical microscopy clearly exhibited damage zone development ahead of a crack-tip of the RT-PMMAs. The three RT-PMMAs revealed different shapes of the damage zone. Transmission electron microscopy exhibited microcrazes nucleated in the equator of rubber particles within the damage zones. Extensive deformation of rubber particles corresponding to localized shear yielding of the PMMA matrix was also found in a region close to a propagating crack-tip. In addition, cavitation of rubber particles was observed in the vicinity of the crack. It is therefore understood that the toughening of the RT-PMMAs is due to energy dissipation caused by the microdamage formations such as microcrazing, matrix shear deformation and rubber particle cavitation ahead of the crack-tip.

著者

Koyasu K Takayanagi T Natsume A Maeda H Kubo K Johgahara T Hanamura H Nakagaki H Kameyama Y Noguchi T

出版者

歯科基礎医学会

雑誌

歯科基礎医学会雑誌 (ISSN:03850137)

巻号頁・発行日

vol.45, no.5, 2003-09-01

著者

QIAN P.-Y. LAU S. C. K. DAHMS H.-U. DOBRETSOV S. HARDER T.

雑誌

Marine biotechnology (ISSN:14362228)

巻号頁・発行日

vol.9, no.4, pp.399-410, 2007-07-01

参考文献数

117

著者

Eto R. Murata A. Uchiyama Y. Okajima K.

出版者

Elsevier

雑誌

Energy policy (ISSN:03014215)

巻号頁・発行日

vol.58, pp.260-268, 2013-07

被引用文献数

8

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This study examines the effects of the inclusion of the co-benefits on the potential installed capacity of carbon dioxide capture and storage (CCS) projects with a linear programming model by the clean development mechanism (CDM) in India's power sector. It is investigated how different marginal damage costs of air pollutants affect the potential installed capacity of CCS projects in the CDM with a scenario analysis. Three results are found from this analysis. First, large quantity of IGCC with CCS becomes realizable when the certified emission reduction (CER) prices are above US$56/tCO2 in the integrated Northern, Eastern, Western, and North-Eastern regional grids (NEWNE) and above US $49/tCO2 in the Southern grid. Second, including co-benefits contributes to decrease CO2 emissions and air pollutants with introduction of IGCC with CCS in the CDM at lower CER prices. Third, the effects of the co-benefits are limited in the case of CCS because CCS reduces larger amount of CO2 emissions than that of air pollutants. Total marginal damage costs of air pollutants of US$250/t and US$200/t lead to CER prices of US$1/tCO2 reduction in the NEWNE grid and the Southern grid.

著者

Daichi Nogami Yuuichi Nakano Y-H.Taguchi

雑誌

研究報告バイオ情報学(BIO)

巻号頁・発行日

vol.2013-BIO-34, no.28, pp.1-2, 2013-06-20

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Inference of subcellular location only using sequence information is important. In this paper, we proposed the application of principal component analysis-based linear discriminant analysis for subcellular location information. It achieved the performance of Area Under the Curve under Receiver Operating Characteristic curve mostly more than 0.95 if less than 80% sequence identity non-redundancy was applied.

著者

Shodai Katsukawa Y-H.Taguchi

雑誌

研究報告バイオ情報学(BIO)

巻号頁・発行日

vol.2013-BIO-34, no.27, pp.1-2, 2013-06-20

---

Type II diabetes (T2D) was a critical symptom also related to other diseases including cancers. Thus, suppression of T2D is important. In this paper, we investigated microRNAs as candidates of drug targets and biomarkers. A recently proposed principal component analysis based linear discriminant analysis allows us to specify numerous miRNAs differently expressed between type II diabetes patients and healthy control. Type II diabetes, Impaired Fasting Glucose patients, and normal control are successfully discriminated by blood miRNAs.

著者

Yuuichi Nakano Mitsuo Iwadate Hideaki Umeyama Y-H.Taguchi

雑誌

研究報告バイオ情報学(BIO)

巻号頁・発行日

vol.2013-BIO-34, no.10, pp.1-8, 2013-06-20

---

Type III secretion system (T3SS) effector protein is a part of bacterial secretion systems. T3SS exists in the pathogenic and symbiotic bacteria. How the T3SS effector proteins in these two classes differ from each other should be interesting. In this paper, we proposed the usage of principal component analysis based linear discriminant analysis that discriminates T3SS effector proteins between plant pathogenic, animal pathogenic and plant symbiotic bacteria by the accuracy of 0.77. We also hypothesized that the feature vector proposed by Yahara et al represents protein structure, possibly protein folds defined in Structural Classification of Proteins (SCOP) database.

著者

Yudai Suzuki Kazunari Yokoyama Naomi Sakuramoto Y-H.Taguchi

雑誌

研究報告バイオ情報学(BIO)

巻号頁・発行日

vol.2013-BIO-34, no.5, pp.1-2, 2013-06-20

---

Soil microbiological biodiversity has recently been shown to be causally related to soil diseases. In this study, we attempted to elucidate soil microbiological interactions by numerically analyzing the carbon-resource consumption rates in soils provided by a number of domestic companies and research institutes.

著者

Kobayakawa T. S. Hatsugai Y. Kohmoto M.

出版者

American Physical Society

雑誌

Physical review E (ISSN:1063651X)

巻号頁・発行日

vol.51, no.6, pp.5365-5370, 1995-06

被引用文献数

9 9

---

Recently, the smoothed correlation between the density of eigenvalues of Hermitian random matrices was found to be universal, that is, independent of the probability distribution from which the random matrices are taken. We study this universal correlation numerically by ensemble averaging, using the Monte Carlo sampling method. Although the density of eigenvalues and the ‘‘bare’’ correlation between the density of eigenvalues are certainly not universal, we find that the smoothed correlation indeed shows a universal behavior. The orthogonal and the symplectic ensembles are also studied numerically. The smoothed correlation is shown to be universal in these cases.

著者

Tomimoto S. Matsubara M. Ogasawara T. Okamoto H. Kimura T. Tokura Y.

出版者

American Physical Society

雑誌

Physical review letters (ISSN:00319007)

巻号頁・発行日

vol.98, no.1, pp.017402, 2007-01

被引用文献数

17

---

Optical manipulation of the magnetic anisotropy is demonstrated for bilayered manganites, La2-2xSr1+2xMn2O7, by means of femtosecond Kerr-rotation measurements. Upon the photoexcitation on the x=0.32 crystal, the magnetization exhibits the precessional motion for about 1 ns, revealing the directional change of the magnetocrystalline anisotropy from the c axis to the ab plane. This change of the anisotropy induces the nonthermal decrease of the c-axis magnetization component for about 1 ns.

著者

Tomimoto S. Miyasaka S. Ogasawara T. Okamoto H. Tokura Y.

出版者

American Physical Society

雑誌

Physical review B (ISSN:01631829)

巻号頁・発行日

vol.68, no.3, pp.035106, 2003

被引用文献数

38 24

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The photoinduced effect on the orbital-ordered phase in perovskite-type LaVO3 has been investigated by femtosecond time-resolved reflection spectroscopy. Large reflectivity change has been observed immediately after photoirradiation. The spectral shape and polarization dependence of the reflectivity change indicate the melting of the orbital order induced by photoexcitation. The photocarriers annihilate in about 200 fs, and the orbital order partially recovers owing to thermalization with the lattice in 2–4 ps.

著者

Nomura S. Tamura H. Yamaguchi M. Akazaki T. Hirayama Y.

出版者

American Physical Society

雑誌

Physical review B (ISSN:10980121)

巻号頁・発行日

vol.87, no.8, pp.085318, 2013-02

被引用文献数

5 1

---

We report on measurement of the electron-hole effective g-factors (geff*) depending on electron filling factors ν from magnetophotoluminescence spectroscopy at low magnetic fields B<1 T in low electron density regime in a GaAs/Al0.33Ga0.67As-gated quantum well. Enhancement of geff* at odd ν is observed. The oscillatory behavior of geff* is compared with results of a theory that takes into account the lowest-order exchange interaction of the screened Coulomb interaction. Good agreement of the observed geff* with theoretical results is obtained except ν at around 3. The enhancement of geff* at even ν with decrease in electron density has not been observed.

著者

YANG L. W. WRIGHT P. D. SHEN H. LU Y. BRUSENBACK P. R. KO S. K. CALDERON L. HARTZLER W. D. HAN W. Y. DUTTA M. CHANG W. H.

出版者

社団法人応用物理学会

雑誌

Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)

巻号頁・発行日

vol.32, no.10, pp.L1400-L1402, 1993-10-01

被引用文献数

1

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Submicron heterojunction bipolar transistors (HBTs) with maximum frequency of oscillation, f_<MAX>, of 91 GHz have been fabricated using a self-aligned technique and a very heavily carbon-doped (10^<20> cm^<-3>) base layer. Since the quenching of photoluminescence (PL) intensity in heavily-doped Cabs is mainly due to nonradiative recombination in the bulk material, while contribution from surface recombination is negligible, the use of a heavily carbon-doped base layer in AlGaAs/GaAs HBTs minimizes the influence of surface recombination in the extrinsic base region. Thus, for HBTs with a heavily doped base layer, the "emitter size effect" (degradation of HBT current gain) is greatly reduced when the emitter width is scaled down to submicron (0.6 μm) dimensions.

著者

Yamagata K Arai C Sasaki H Takeuchi Y Onizawa K Yanagawa T Ishibashi N Karube R Shinozuka K Hasegawa Y Chiba S Bukawa H

出版者

Nature Publishing Group

雑誌

Bone marrow transplantation (ISSN:02683369)

巻号頁・発行日

vol.47, pp.725-730, 2012-05

被引用文献数

25 6

---

Oral mucositis (OM) is a frequent adverse effect of allogenic or autologous hematopoietic SCT. It results from direct toxic injury to the mucosal epithelial cells by the immunosuppressive regimen. Here, we compared the incidence and severity of OM between a group of 24 patients who received proper oral management during hematopoietic SCT and a group of 24 who did not. The oral management group received pre-hematopoietic SCT instruction on oral care and an oral examination in the clean room. Differences in the incidence and severity of OM between the two groups were examined statistically. OM was observed in 14 (58.3%) patients in the oral management group and 22 (91.6%) in the control group. The median of the OM score was 1 for the oral management group (range 0 to 3) and 2 for the control group (range 0 to 3). There was a significant difference in the OM score (P<0.05) and in the incidence of OM between the two groups (P<0.01). This study shows that oral management may decrease the occurrence of OM. Our results also suggest that it is important to include an oral management provider on the hematopoietic SCT team.

著者

Yoichi Takahashi [traducción Marc Bernabé y Verònica Calafell]

出版者

Glénat

巻号頁・発行日

2003

著者

Takahashi Y. Hara K. Kim S. Ikegami Y. Takubo Y. Terada S. Unno Y. Mitsui S. Kamada S. Yamamura K.

出版者

Elsevier B.V.

雑誌

Nuclear instruments & methods in physics research. Section A (ISSN:01689002)

巻号頁・発行日

vol.699, pp.107-111, 2013-01

被引用文献数

1 1

---

We are developing p-bulk microstrip sensors for the high luminosity upgrade of the LHC accelerator, HL-LHC. The stability of FZ (float zone) wafers available to Hamamatsu Photonics was examined by irradiating them at rates expected at the HL-LHC. They show degradation in the operational voltage at low dose but recover after the dose is accumulated. The instability is dependent on the bias voltage and dose rate, and also on the irradiation history. We have characterized the instability and attributed the cause to the charge concentration at the electrode edge. The strip isolation, which is degraded while in irradiation, is shown not to induce any practical problem for the operation.

著者

Otsuka Y. Hatsugai Y.

出版者

American Physical Society

雑誌

Physical review B (ISSN:01631829)

巻号頁・発行日

vol.65, no.7, pp.073101, 2002-01

被引用文献数

16

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Effects of the electron-electron interaction in the two-dimensional flux phase are investigated. We treat the half-filled Hubbard model with a magnetic flux π per plaquette by the quantum Monte Carlo method. When the interaction is small, an antiferromagnetic long-range order does not exist. It suggests that the Mott transition occurs at finite strength of the interaction in the flux phase, which is in contrast to the standard Hubbard model.

著者

Gerlovin I. Ya. Dolgikh Yu. K. Eliseev S. A. Ovsyankin V. V. Efimov Yu. P. Petrov V. V. Ignatiev I. V. Kozin I. E. Masumoto Y.

出版者

American Physical Society

雑誌

Physical review B (ISSN:10980121)

巻号頁・発行日

vol.65, no.3, pp.035317, 2002-01

被引用文献数

21 17

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Picosecond kinetics of polarized resonant photoluminescence (PL) of HH excitons in the GaAs/AlGaAs superlattices is studied in an external magnetic field. The measurements were made in real time using a streak camera. For the magnetic field aligned along the heterostructure growth direction, the resonant PL exhibits oscillations in the degree of linear polarization. The oscillations are ascribed to quantum beats between sublevels of the optically active excitonic doublet split by the magnetic field. For the magnetic field aligned along the plane of the layers, the resonant PL is found to exhibit oscillations in circular polarization. These oscillations are related to beats between states of the optically active and optically inactive excitonic doublets. Experimental dependence of the oscillation frequency on the magnetic field strength and orientation has allowed us to determine the hole and electron g factors and the electron-hole exchange energy. Dynamics of the degree of circular polarization of the PL in magnetic field is used to measure the energy relaxation rate of the exciton spin states. In the magnetic field exceeding 1 T, the energy relaxation rate is shown to be magnetic-field independent and equal (1±0.2)×1010 s-1. This value is found to be much smaller than the spin phase relaxation rate determined from decay of the quantum beats in linear polarization. Unlike the energy relaxation rate, the latter grows linearly with the field strength and equals (5±0.5)×1010 s-1 at 5 T. It is concluded that the main mechanism responsible for loss of macroscopic spin coherence is the reversible dephasing within inhomogeneously broadened system.