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131.
cis-Decalin (2) and perylene (3) are co-enclathrated by a self-assembled M6L4-coordination cage (1) to give 1 superset(2.3) although each of them is not enclathrated. This phenomenon is termed as AND bimolecular recognition because enclathration occurs only if 2 and 3 coexist. Cage 1 also coenclathrates azulene (8) and 1,4-naphthoquinone (9) to give 1 superset(8.9). In this case, 1 superset(8)2 and 1 superset(9)2 are formed by treating 1 with 8 and 9 individually. This case is termed as OR bimolecular recognition because enclathration occurs if 8 or 9 exists. Accordingly, we have shown that the self-assembled cage 1 experiences both AND and OR bimolecular recognition. 相似文献
132.
K.?MizoguchiEmail author S.?Fujita M.?Nakayama 《Applied Physics A: Materials Science & Processing》2004,78(4):461-464
We report the first observation of coherent phonons in crystalline lead phthalocyanine (PbPc) films grown on a (0001) sapphire substrate by using a pump–probe technique. Coherent phonon oscillations corresponding to intermolecular (lattice) vibrations in the PbPc film are observed in the frequency region from 1 to 5 THz. It is found that the intensities of coherent phonons are resonantly enhanced at the exciton energies of the Q band observed in the absorption spectrum. PACS 78.47.+p; 78.66.-w; 82.53.Xa; 78.40.Me 相似文献
133.
Takeishi S Rant U Fujiwara T Buchholz K Usuki T Arinaga K Takemoto K Yamaguchi Y Tornow M Fujita S Abstreiter G Yokoyama N 《The Journal of chemical physics》2004,120(12):5501-5504
DNA oligo-nucleotides, localized at Au metal electrodes in aqueous solution, are found to be released when applying a negative bias voltage to the electrode. The release was confirmed by monitoring the intensity of the fluorescence of cyanine dyes (Cy3) linked to the 5' end of the DNA. The threshold voltage of the release changes depending on the kind of linker added to the DNA 3'-terminal. The amount of released DNA depends on the duration of the voltage pulse. Using this technique, we can retain DNA at Au electrodes or Au needles, and release the desired amount of DNA at a precise location in a target. The results suggest that DNA injection into living cells is possible with this method. 相似文献
134.
Itami K Mitsudo K Fujita K Ohashi Y Yoshida J 《Journal of the American Chemical Society》2004,126(35):11058-11066
Some circumstantial evidence for the directing effect of the 2-pyridylsilyl group in the Ru-catalyzed intermolecular Pauson-Khand-type reaction (PKR) of alkenyl(2-pyridyl)silane, alkyne, and carbon monoxide has been provided. Most importantly, we have succeeded in isolating several monometallic Ru complexes relevant to the catalytic reaction: Ru(vinylsilane)(CO)(3) complexes and ruthenacyclopentene. While the stoichimetric reaction of the Ru(vinylsilane)(CO)(3) complex with an alkyne led to the formation of the corresponding cyclopentenone (PKR product) at 100 degrees C, the ruthenacyclopentene intermediate was quantitatively produced at 50 degrees C. This complex was also converted to a cyclopentenone upon heating at 100 degrees C. Moreover, it was also found that the Ru(vinylsilane)(CO)(3) complex and ruthenacyclopentene serve as catalysts in intermolecular PKR. 相似文献
135.
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
136.
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
137.
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
138.
139.
140.
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