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151.
Lucarelli A Lupi S Ortolani M Calvani P Maselli P Capizzi M Giura P Eisaki H Kikugawa N Fujita T Fujita M Yamada K 《Physical review letters》2003,90(3):037002
While there is increasing evidence for antiferromagnetic (AF) ordering in the Cu-O planes of high-T(c) superconductors, either static or fluctuating, there is no direct evidence so far for the charge stripes that should separate the AF domains. By investigating the optical response of La2-xSrxCuO4 for 0相似文献
152.
Zegers RG Abend H Akimune H van den Berg AM Fujimura H Fujita H Fujita Y Fujiwara M Galès S Hara K Harakeh MN Ishikawa T Kawabata T Kawase K Mibe T Nakanishi K Nakayama S Toyokawa H Uchida M Yamagata T Yamasaki K Yosoi M 《Physical review letters》2003,90(20):202501
The excitation and subsequent proton decay of the isovector spin-flip giant monopole resonance (IVSGMR) is studied via the 208Pb(3He,t) reaction at 410 MeV. In the inclusive spectrum (60+/-5)% of the non-energy-weighted sum-rule strength for this 2 variant Planck's over 2h omega resonance was found in the region 29相似文献
153.
Hori A Kataoka H Okano T Sakamoto S Yamaguchi K Fujita M 《Chemical communications (Cambridge, England)》2003,(2):182-183
The reversible cross-catenation of two different coordination rings (Pd(II)- and Pt(II)-linked rings) has been achieved by using the labile nature of the Pd-N interaction and efficient hydrophobic contact between the rings. 相似文献
154.
155.
156.
Sugiyasu K Fujita N Takeuchi M Yamada S Shinkai S 《Organic & biomolecular chemistry》2003,1(5):895-899
A 1,10-phenanthroline-appended cholesterol-based gelator (1) and its nongelling reference compound (2) were synthesized. Among 19 solvents tested herein, gelator 1 could gelate 11 solvents including alcohols, dipolar aprotic solvents, organic acids and a base (triethylamine), indicating that 1 acts as a versatile gelator. The TEM observation gave a visual image showing that fibrillar aggregates are entangled in the three-dimensional network structure. In the fluorescence measurements, most gels afforded an emission maximum at 394 nm (purple emission), whereas only the acetic acid gel afforded an emission maximum at 522 nm (yellow emission). Thus, the influence of protonation of the 1,10-phenanthroline nitrogens (by trifluoroacetic acid) on the fluorescence properties in the gel phase was investigated in detail. The results have established that the fluorescence intensity of 1 x H+ becomes particularly strong in the gel phase, presumably because of the energy transfer from neutral 1* to protonated 1 x H+ and the restriction of the 1 x H+ molecular motion. The finding suggests the possibility that the gel system would be useful not only as a new proton-sensitive fluorescence system but also as a new medium for designing efficient energy transfer systems. 相似文献
157.
Hou Z Koizumi T Fujita A Yamazaki H Wakatsuki Y 《Journal of the American Chemical Society》2001,123(24):5812-5813
158.
Abe K Abe K Adachi I Ahn BS Aihara H Akatsu M Alimonti G Aoki K Asai K Asai M Asano Y Aso T Aulchenko V Aushev T Bakich AM Banas E Behari S Behera PK Beiline D Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Cheon BG Choi SK Choi Y Doi Y Dragic J Eidelman S Enari Y Enomoto R Everton CW Fang F Fujii H Fujita Y Fukunaga C Fukushima M Garmash A Gordon A Gotow K Guler H Guo R Haba J Haji T Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashi K Hayashii H Hazumi M Heenan EM Higuchi I 《Physical review letters》2001,86(15):3228-3232
We report a determination of the B(0)(d)-&B_(0)(d) mixing parameter Deltam(d) based on the time evolution of dilepton yields in Upsilon(4S) decays. The measurement is based on a 5.9 fb(-1) data sample collected by the Belle detector at KEKB. The proper-time difference distributions for same-sign and opposite-sign dilepton events are simultaneously fitted to an expression containing Deltam(d) as a free parameter. Using both muons and electrons, we obtain Deltam(d) = 0.463+/-0.008 (stat)+/-0.016 (syst) ps(-1). This is the first determination of Deltam(d) from time evolution measurements at the Upsilon(4S). We also place limits on possible CPT violations. 相似文献
159.
Irradiation of ultrasound accelerated the rate of the photochemical disappearance of 4,4'-dihalogenated benzils in 1,4-dioxane in the order of halogen = I, Br > Cl > F. 4,4'-dimethoxy and unsubstituted benzils did not show acceleration. Possible mechanisms of the acceleration are discussed. 相似文献
160.
One-dimensional quasilattices, namely, the geometrical objects that represent quasicrystals, are classified into mutual local-derivability (MLD) classes. Besides the familiar class, there exist an infinite number of new MLD classes, and different MLD classes are distinguished by the inflation rules of their representatives. It has been found that electronic properties of a new MLD class are characterized by the presence of marginal critical states, which are considered to be nearly localized states. 相似文献