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71.
72.
Jun Takahashi Kazuto Kawakami Yukiko Kobayashi 《Surface and interface analysis : SIA》2019,51(1):12-16
Although steel research has a very long history, there are still various questions and uncertainties on the fundamental issues of steel materials. Our aim is to clarify the issues by atomic-scale characterization using atom probe tomography (APT). This paper introduced our developed techniques in application of APT into steel materials. The first one is the specimen tip preparation technique from the site-specific regions of interest in steel, which significantly expanded the application field of steel analysis. The second one is the observation technique of trapped hydrogen in steel using our developed “deuterium charge cell,” which accomplished direct observation of the hydrogen trapping site in alloy carbide precipitation strengthened steels. Such atomic-scale analyses bring many new findings in steel materials science. 相似文献
73.
Takahashi Hiroaki Park Ki Chul Nomura Masao Shibahara Hiroki Miura Hanako Ohishi Yukiko Yuki Mami Tsukahara Takehiko 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):327-336
Journal of Radioanalytical and Nuclear Chemistry - The influence of extraction process on Cs isotope ratios was investigated by thermal ionization mass spectrometry (TIMS) for nitric-acid (HNO3)... 相似文献
74.
Yukiko Enomoto Hiroshi Kamitakahara Toshiyuki Takano Fumiaki Nakatsubo 《Cellulose (London, England)》2006,13(4):437-448
Novel cellobiose and cellulose (DP
n
=ca. 30) derivatives, N-(1-pyrenebutyloyl)-4-O-(β-d-glucopyranosyl)-β-d-glucopyranosylamine (6), N-(15-(1-pyrenebutyloylamino)-pentadecanoyl)-4-O-(β-d-glucopyranosyl)-β-d-glucopyranosylamine (7), N-(1-pyrenebutyloyl)-β-cellulosylamine (13), N-(15-(1-pyrenebutyloylamino)-pentadecanoyl)-β-cellulosylamine (14) carrying a pyrene group as a single fluorescent probe at the reducing end, were prepared in order to investigate their self-assembly systems in solutions. The relative intensity of the excimer emission at ca. 480 nm due to dimerized pyrenes (intensity I
E) to the monomer emission at ca. 380 nm due to isolated pyrene (intensity I
M), i.e., I
E/I
M, was monitored in various solutions. In water/dimethyl sulfoxide (DMSO) mixed solvent (0–98%, v/v), the ratio I
E/I
M remained low (0.04) for compound 6 over the range of water concentrations, indicating that pyrenes at C-1 position of compound 6 were diffused. On the other hand, the ratio I
E/I
M increased (0.04–4.96) for compound 7 with the increase in water concentration, indicating that pyrenes at C-1 position were associated. In aqueous NaOH solutions (4.4–17.5%, w/w), compound 14 showed a large increase in the ratio I
E/I
M (0.84–8.14) with the increase in NaOH concentration, compared to compound 13 (0.06–0.41). It was found that the association of hydrophobic groups at the reducing-end of cellulose could be controlled by the hydrophilic–hydrophobic balance of compounds and the solvent polarity. 相似文献
75.
Liquid‐Crystalline Biomacromolecular Templates for the Formation of Oriented Thin‐Film Hybrids Composed of Ordered Chitin and Alkaline‐Earth Carbonate 下载免费PDF全文
Dr. Tatsuya Nishimura Ken Toyoda Takahiro Ito Dr. Yuya Oaki Yukiko Namatame Prof. Takashi Kato 《化学:亚洲杂志》2015,10(11):2356-2360
Macroscopically ordered inorganic thin films have been formed on unidirectionally oriented, liquid‐crystalline chitin matrices. In the presence of poly(acrylic acid) (PAA), unidirectionally oriented chitin films act as templates for the formation of oriented thin‐film crystals of alkaline‐earth carbonates such as SrCO3 and BaCO3. The morphology and orientation of crystals are dependent on the metal ion concentration. For SrCO3 crystallization, unidirectional thin films and hexagonal‐shaped thin films have been deposited from 200 and 25 mm concentration strontium solutions, respectively. 相似文献
76.
77.
Akito Iwasaki Laigui Hu Dr. Rie Suizu Dr. Kenji Nomura Hirofumi Yoshikawa Dr. Kunio Awaga Prof. Yukiko Noda Kaname Kanai Dr. Yukio Ouchi Prof. Kazuhiko Seki Prof. Hiroshi Ito Prof. 《Angewandte Chemie (International ed. in English)》2009,48(22):4022-4024
Fully interactive : Overlap between extended unoccupied molecular orbitals leads to the high photoconductivity of interactive radical dimers. Sandwich‐type cells (see picture; ITO=indium tin oxide) comprising highly oriented thin films of a disjoint diradical, 4,4′‐bis(1,2,3,5‐dithiadiazolyl) (BDTDA) exhibit a photocurrent with a high on/off ratio at reverse bias voltages and photovoltaic behavior at zero bias voltage.
78.
A reagent tablet for determination of fluoride ion has been prepared using ethylenediamine-N,N,N′,N′-tetraacetate complex of zirconium (Zr-EDTA), 3-hydroxy-2′-flavone (FS) and an appropriate pH buffer. Dissolving of the tablet into water exhibits an intense blue fluorescence (λmax = 460 nm) upon excitation at 377 nm and the fluorescence intensity decreases with the presence of fluoride ion. Hence, a simple fluorescent detection procedure for fluoride ion in aqueous media was successfully constructed with this tablet. The principle of this detection system is the ligand exchange reaction of FS bound to Zr-EDTA with fluoride ion. The present system provides an easy, rapid and selective determination method of fluoride ion ranging from 5 × 10−6 to 1 × 10−3 mol dm−3. The measurement of real samples with this tablet showed the similar results as those by the common method with the Alfusone reagent. 相似文献
79.
80.
Brownian dynamics simulations of the gating mechanism of the extracellular loops of the β2-adrenergic receptor suggest that loop gating alone will not permit the larger ligands to bind and hence suggests that lateral helix movement is also required in the binding process. 相似文献