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11.
Narihara K Watanabe KY Yamada I Morisaki T Tanaka K Sakakibara S Ida K Sakamoto R Ohyabu N Ashikawa N Emoto M Funaba H Goto M Hayashi H Idei H Ikeda K Inagaki S Inoue N Kaneko O Kawahata K Kobuchi T Komori A Kubo S Kumazawa R Masuzaki S Miyazawa J Morita S Motojima O Murakami S Muto S Mutoh T Nagayama Y Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohdachi S Oka Y Ohkubo K Osakabe M Ozaki S Peterson BJ Sagara A Saito K Sasao H Sasao M Sato K Sato M Seki T Shimozuma T Shoji C Sudo S 《Physical review letters》2001,87(13):135002
It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced. 相似文献
12.
Difference systems of sets (DSS) are combinatorial configurations that arise in connection with code synchronization. A method for the construction of DSS from partitions of cyclic difference sets was introduced in [V.D. Tonchev, Difference systems of sets and code synchronization, Rend. Sem. Mat. Messina, Ser. II, t. XXV 9 (2003) 217–226] and applied to cyclic difference sets (n,(n-1)/2,(n-3)/4) of Paley type, where is a prime number. This paper develops similar constructions for prime numbers that use partitions of the set of quadratic residues, as well as more general cyclotomic classes. 相似文献
13.
Asymmetric Darzens reaction catalyzed by chiral selenides is described. A novel Lewis acid/Brønsted base catalyst formed by C2 symmetric chiral selenide-bearing isoborneol skeletons, which were readily prepared from (1S)-10-camphorsulfonic acid, and LiOH promoted the reaction of phenacyl bromide with aldehydes to afford the desired trans oxiranes with up to 62% ee. 相似文献
14.
Fracture theory is a classic, but not a well-dealt with, difficulty in solid mechanics. This paper has proposed the concept
of characteristic fracture length of materials from the fact that fracture happens with area failure rather than point failure
in materials. A unified theory is then proposed, which can be applied both to smooth and defected materials (whether with
micro or macro defects). Brittle fracture tests with specimens of different sizes of holes are carried out to examine the
fracture theory. It is found that the fracture stresses obtained by experiments agree well with those predicated by the presented
fracture theory. Though the brittle fracture is the focus of the paper, the concept of characteristic length can be easily
extended to fatigue or other failure problems. 相似文献
15.
The three-dimensional theoretical solution of a concentrated normal force acting on the free surface of a coated material has been deduced by applying the reflection method. It is found that all stress functions defined in the local coordinate systems with their origins placed at each mirror point can be deduced from the fundamental solution of a concentrated normal force acting on the free surface of a semi-infinite homogeneous medium. The structure of the elastic solution has been illustrated by numerical analysis. It is found that only the stress functions corresponding to the first few mirror points are influential. It is also found that the effect of material combination on the stress field shall be described by three parameters, the two Dundurs' parameters and one additional parameter. 相似文献
16.
This paper presents a low-capacity cation-exchange chromatography method for the analysis of UV-absorbing dipeptides and amino acids. A newly marketed low-capacity cation-exchange column packed with sulfo-functionalized highly cross-linked macroreticular poly(ethylstyrene-divinylbenzene) copolymer was used for the simultaneous determination of imidazole amino acids, aromatic amino acids, and creatinine in urine samples. A dual-mode binary gradient chromatography method was established using two solvents, A: 15 mM H3PO4/5 mM ethylenediamine and B: 15 mM H3PO4/5 mM ethylenediamine/40 (v/v) % CH3CN at 40 °C, with an optimized time program for changing the delivery ratio of A/B and the flow rate. Good chromatograms were obtained within an acceptable cycle time of 25 min. The quantification data were satisfactory for all analytes, showing the relative standard deviations (RSD) of retention times between 0.08 and 1.68 %; RSDs of area intensities between 0.23 and 2.60 %; and linear regression lines with r 2 more than 0.9994. The method could determine the creatinine ratios of the diagnostic markers on the single chromatographic run, which enabled to discriminate disease from health. For example, the creatinine ratios for phenylketonuria were significantly higher than those for controls. The method can provide highly cost-efficient information or useful knowledge for clinical and pharmaceutical studies. 相似文献
17.
Masakatsu Saeki Masami Nakada Nobuyuki M. Masaki Zenko Yoshida Kazutoyo Endo Yoshitaka Minai Toshiyuki Yamashita Hiroshi Mutoh Masaaki Magara 《Hyperfine Interactions》1994,92(1):1177-1181
Experiments on the57Fe Mössbauer effect in frozen solutions were carried out in order to demonstrate the capabilities of a cryostat which was developed for the emission Mössbauer spectroscopy of237Np. We confirmed the existence of an aliovalent state of57Fe in the temperature range from 5.5 to 35 K. However, the relative amounts of Fe(II) and Fe(III) in the frozen matrix were almost constant for the temperature range from 5.5 to 150 K. The design, operation and capabilities of the cryostat are also described. 相似文献
18.
Seiji Yamaguchi Masao Mutoh Masaaki Shimakura Kunihiro Tsuzuki Yoshiyuki Kawase 《Journal of heterocyclic chemistry》1991,28(1):119-123
Some ω-(3-chromonyl)alkanoic acid derivatives, 1a and 2a , n = 4, 5; 3a, 4a and 5a , n = 2-6, were synthesized by cyclization of corresponding methyl ω-(2-hydroxybenzoyl)alkanoates 7b or ethyl ω-(2,4-dihydroxybenzoyl)alkanoates 8b with N,N-dimethylformamide-dimethyl acetal or acetic anhydride-DBU followed by hydrolysis. 相似文献
19.
Tuning the Electronic Properties and Acid‐Response Behavior of N‐Heteroacene‐Based π‐Conjugated Liquids by Changing the Number of π‐Conjugated Substituents 下载免费PDF全文
Yuika Sato Dr. Yuichiro Mutoh Dr. Daisuke Matsukuma Makoto Nakagawa Prof. Takeshi Kawai Dr. Kyosuke Isoda 《化学:亚洲杂志》2018,13(18):2619-2625
We have designed and synthesized two room‐temperature‐fluorescent π‐conjugated liquids based on the N‐heteroacene framework ( 1 and 2 ). These two π‐conjugated liquids, which contained one and two thiophene rings, respectively, exhibited different electronic properties and rheology behaviors. Single‐crystal X‐ray analysis of dithiophene‐appended compound 4 revealed that two thiophene rings hindered the interactions of the imino N atoms with acids through the formation of interactions between the S atoms of the thiophene rings and the imino N atoms of the pyrazine group. On the other hand, monothiophene‐appended molecules 1 and 3 each contained an unhindered imino N atom on the opposite site to the thiophene ring. Upon dissolving various acids with different pKa values in compounds 1 and 2 , these slight structural differences gave rise to marked differences in their acid‐response behaviors, thereby resulting in the emission of variously colored fluorescence in the liquid state. Furthermore, when acids with lower pKa values was dissolved in compounds 1 and 2 , phase transition occurred from an isotropic liquid state to a self‐organized liquid‐crystalline phase. 相似文献
20.
New Types of Planar Chiral [2.2]Paracyclophanes and Construction of One‐Handed Double Helices 下载免费PDF全文
Prof. Yasuhiro Morisaki Risa Sawada Dr. Masayuki Gon Prof. Yoshiki Chujo 《化学:亚洲杂志》2016,11(18):2524-2527
New types of planar chiral (Rp)‐ and (Sp)‐4,7,12,15‐tetrasubstituted [2.2]paracyclophanes were synthesized from racemic 4,12‐dihydroxy[2.2]paracyclophane as the starting compound. Regioselective dibromination and transformation afforded a series of planar chiral (Rp)‐ and (Sp)‐4,7,12,15‐tetrasubstituted [2.2]paracyclophanes, which can be used as chiral building blocks. In this study, left‐ and right‐handed double helical structures were constructed via chemoselective Sonogashira–Hagihara coupling. The double helical compounds were excellent circularly polarized luminescence (CPL) emitters with large molar extinction coefficients, good photoluminescence quantum efficiencies, and large CPL dissymmetry factors. 相似文献