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361.
D. Kameda H. Ueno K. Asahi D. Nagae M. Takemura K. Shimada A. Yoshimi T. Nagatomo T. Sugimoto M. Uchida T. Arai K. Takase S. Suda T. Inoue J. Murata H. Kawamura H. Watanabe Y. Kobayashi M. Ishihara 《Hyperfine Interactions》2007,180(1-3):61-64
The electric quadrupole moments for the ground states of 32Al and 31Al have been measured by the β ray-detected nuclear quadrupole resonance method. Spin-polarized 32Al and 31Al nuclei were obtained from the fragmentation of 40Ar projectiles at E/A?=?95 MeV/nucleon, and were implanted in a single crystal α-Al2O3 stopper. The measured Q moment of 32Al, |Q(32Al)|?=?24(2) mb, is in good agreement with a conventional shell-model calculation with a full sd model space and empirical effective charges, while that of 31Al is considerably smaller than the sd calculations. 相似文献
362.
V. P. Ladygin T. Uesaka V. V. Glagolev Yu. V. Gurchin A. Yu. Isupov K. Itoh M. Janek J. -T. Karachuk T. Kawabata A. N. Khrenov A. S. Kiselev V. A. Krasnov A. B. Kurepin A. K. Kurilkin P. K. Kurilkin N. B. Ladygina D. Lipchinski Y. Maeda A. I. Malakhov G. Martinska S. Nedev S. M. Piyadin J. Popovichi S. Rangelov S. G. Reznikov P. A. Rukoyatkin S. Sakaguchi H. Sakai K. Sekiguchi M. A. Shikhalev K. Suda A. A. Terekhin B. Trpisova J. Urban T. A. Vasiliev I. E. Vnukov H. Witala 《Physics of Particles and Nuclei》2014,45(1):327-329
The review of the recent results on spin effects in few nucleon systems obtained at LHEP-JINR are presented. The data on the deuteron analyzing powers in different reactions in the wide energy range demonstrate the sensitivity to the spin structure of the light nuclei. The future plans on the studies with polarized deuterons from new polarized ion source at Nuclotron will be reported. 相似文献
363.
Satoshi Morita Kazuyuki Ikezawa Hiroshi Inoue Natsuki Yamashita Toshihisa Maeshima 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(9):1495-1505
The anionic copolymerizations of acrolein (AL) with methyl vinyl ketone (MVK) and acrylamide (AAm) in the presence of imidazole (Im) as an initiator have been studied in tetrahydrofuran at 0°C. The AL-MVK copolymers were found to be composed of vinyl polymer with one Im group attached and having an aldehyde and a carbonyl side chain. The monomer reactivity ratio was determined from a Fineman-Ross plot as r1 = 2.02 and r2 = 0.06. On the other hand, the AL-AAm copolymer were found to be composed of polymer units of 1,2 and 1,4 addition polymerization of AAm. These observations might be explained by the intermolecular hydrogen transfer mechanism of AAm. The polymerization mechanisms were discussed on the basis of these copolymerization results. 相似文献
364.
Natsuki Yamashita Kazuyukiikezawa Shin-Ichirou Ayukawa Toshihisa Maeshima 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):615-629
Radical copolymerization of methyl vinyl ketone (MVK, M1) with acrylamide (AAm) and its derivatives, such as methacrylamide (MAAm) and N,N′ -dimethylacrylamide (DMAAm), was carried out in dioxane or ethanol using α,α - azobisisobutylonitrile as the initiator at 60°C under vacuum. The monomer reactivity ratios found in dioxane were as follows: ri = 1.06, r2 = 6.41 for the MVK-AAm system; r1 = 0.29, r2 = 3.05 for the MVK-MAAm system; and r1 = 0.95, r2 = 0.26 for the MVK-DMAAm system. The n and r2 values obtained in ethanol were as follows: r1 = 0.88, r2 = 1.18 for the MVK-AAm system; and r1 = 0.37, r2 = 2.04 for the MVK-MAAm system. Q2 and e2 values of AAm derivatives in dioxane were estimated to be 3.03 and 1.04 for MAAm and 2.15 and 1.11 for DMAAm, respectively. The Q2 and e2 values of MAAm in ethanol were estimated to be 2.67 and 1.21, respectively. Based on these results, the alternating copolymerizability depends on the interaction of monomer-monomer, and the strong solvent effect depends on the radical copolymerization of the AAm derivatives. 相似文献
365.
Kazuhiro Kobayashi Natsuki Konishi Teruhiko Suzuki Kazuhiro Nakagawa 《Helvetica chimica acta》2013,96(8):1452-1456
An efficient one‐pot synthesis of novel heterocyclic derivatives, 2‐aryl‐1,4‐oxathiino[2,3‐b]quinoxalines or ‐pyrazines 5 , via the reaction of 2,3‐dichloroquinoxaline or ‐pyrazine with Na2S?9 H2O, and subsequent treatment of the resulting 2‐chloro‐3‐sodiosulfanylquinoxaline or ‐pyrazine 2 with 1‐aryl‐2‐bromo‐1‐alkanones and then NaH under mild conditions is described. 相似文献
366.
Balancedly splittable Hadamard matrices are introduced and studied. A connection is made to the Hadamard diagonalizable strongly regular graphs, maximal equiangular lines set, and unbiased Hadamard matrices. Several construction methods are presented. As an application, commutative association schemes of 4, 5, and 6 classes are constructed. 相似文献
367.
This paper describes a practical and convenient method to prepare stable colloidal silver nanoparticles for use in printed electronic circuits. The method uses a dispersant and two kinds of reducing agents including 2-(dimethylamino) ethanol (DMAE), which play important roles in the reduction of silver ions in an aqueous medium. The effect of DMAE and dispersant, as well as the factors affecting particle size and morphology are investigated. In the formation of the silver nanoparticles, reduction occurs rapidly at room temperature and the silver particles can be separated easily from the mixture in a short time. In addition, organic solvents are not used. Pure, small and relatively uniform particles with a diameter less than 10 nm can be obtained that exhibit high electroconductivity. The silver nanoparticles are stable, and can be isolated as a dried powder that can be fully redispersed in deionized water. This method of producing colloidal silver nanoparticles will find practical use in electronics applications. 相似文献
368.
Shimoyama A Saeki A Tanimura N Tsutsui H Miyake K Suda Y Fujimoto Y Fukase K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(51):14464-14474
Helicobacter pylori is a common cause of gastroduodenal inflammatory diseases such as chronic gastritis and peptic ulcers and also an important factor in gastric carcinogenesis. Recent reports have demonstrated that bacterial inflammatory processes, such as stimulation with H. pylori lipopolysaccharide (LPS), initiate atherosclerosis. To establish the structures responsible for the inflammatory response of H. pylori LPS, we synthesized various kinds of lipid A structures (i.e., triacylated lipid A and Kdo‐lipid A compounds), with or without the ethanolamine group at the 1‐phosphate moiety, by a new divergent synthetic route. Stereoselective α‐glycosylation of Kdo N‐phenyltrifluoroacetimidate was achieved by use of microfluidic methods. None of the lipid A and Kdo‐lipid A compounds were a strong inducer of IL‐1β, IL‐6, or IL‐8, suggesting that H. pylori LPS is unable to induce acute inflammation. In fact, the lipid A and Kdo‐lipid A compounds showed antagonistic activity against cytokine induction by E. coli LPS, except for the lipid A compound with the ethanolamine group, which showed very weak agonistic activity. On the other hand, these H. pylori LPS partial structures showed potent IL‐18‐ and IL‐12‐inducing activities. IL‐18 has been shown to correlate with chronic inflammation, so H. pylori LPS might be implicated in the chronic inflammatory responses induced by H. pylori. These results also indicated that H. pylori LPS can modulate the immune response: NF‐κB activation through hTLR4/MD‐2 was suppressed, whereas production of IL‐18 and IL‐12 was promoted. 相似文献
369.
P. K. Kurilkin V. P. Ladygin T. Uesaka K. Suda Yu. V. Gurchin A. Yu. Isupov K. Itoh M. Janek J. -T. Karachuk T. Kawabata A. N. Khrenov A. S. Kiselev V. A. Kizka V. A. Krasnov N. B. Ladygina A. N. Livanov Y. Maeda A. I. Malakhov S. G. Reznikov S. Sakaguchi H. Sakai Y. Sasamoto K. Sekiguchi M. A. Shikhalev T. A. Vasiliev 《Physics of Particles and Nuclei Letters》2011,8(10):1081-1083
New polarimeter based on the asymmetry measurement in dp-elastic scattering has been constructed at internal target at Nuclotron (JINR). The result on the deuteron analyzing powers A y , A yy and A xx in the deuteron-proton (dp) elastic scattering at the energies of 880 and 2000 MeV are presented. They are compared with different theoretical approaches. 相似文献
370.
A. Okada K. Mitsui T. Kitamura Y. Ohashi Y. Muraki T. Suda I. Nakamura Y. Kawashima S. Matsuno F. Kajino T. Aoki S. Higashi S. Ozaki T. Takahashi K. Honda K. Kobayakawa H. Inazawa Y. Minorikawa M. Shibata H. Shibata Y. Kamiya Y. Teramoto 《Fortschritte der Physik》1984,32(4):135-173
Hadronic cascade showers originating from inelastic interactions of cosmic ray muons with iron nuclei have been observed in a calorimeter located between two magnetic spectrometers. The separation of those events from the electromagnetic showers has been successfully done in the ranges of the transferred energy v ≳ 50 GeV and its ratio to muon energy v/E ≳ 0,1, by utilizing the difference of their longitudinal cascade developments. The comparison of the obtained μ-Fe cross section with available μ-, e- and σ-proton data as well as μ-, e- and σ-nucleus data indicates that;
- 1 At v ˜ 100 GeV, the virtual photon cross section on iron nucleus is almost the same as the real photon one, at least Q2 ≳ 0.1 GeV2/c2, and is about 70% of the cross section on proton times the atomic mass number of iron, i.e. the shadowing effect is clearly seen.
- 2 Up to TeV region, this virtual photon cross section on iron does not increase significantly. contrary to the tendency of the real photon cross section on proton around 100 GeV. This suggests most likely that the shadowing still increases with energy at such high energies.