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991.
Takeshi Yamazaki Dr. Hicham Fenniri Prof. Dr. Andriy Kovalenko Prof. Dr. 《Chemphyschem》2010,11(2):361-367
We reveal how water solvent determines the self‐assembly pathway and stability of organic rosette nanotubes (RNTs) and show their possible functions, using three‐dimensional molecular theory of solvation (a.k.a. 3D‐RISM). Structural water molecules penetrate the pockets on the RNT outer surface, form a wetting monolayer in the RNT channel and bridge RNT rosettes. We predict that the inner water shell might stabilize rare gas atoms inside the RNT channel, and envision molecular devices with RNT channels transporting water or holding guest molecules for targeted delivery. 相似文献
992.
Yagi M Toda M Yamada S Yamazaki H 《Chemical communications (Cambridge, England)》2010,46(45):8594-8596
Visible-light-derived O(2) production was yielded by conjugating water oxidation catalysis by [(OH(2))(terpy)Mn(μ-O)(2)Mn(terpy)(OH(2))](3+) as an oxygen evolving center model and photo-sensitization of [Ru(bpy)(3)](2+) as a photoexcitation center model at an interlayer of mica. 相似文献
993.
Shigenobu Nishiguchi Akihiro Taguchi Tetsuya Kajimoto Yuri Yamazaki Yoshiaki Kiso 《Tetrahedron》2010,66(1):314-227
(+)-Negamycin was prepared in 13 steps in an overall yield of 31% from commercially available ethyl (R)-(+)-4-chloro-3-hydroxybutanoate. The key step in the reaction sequence was a highly stereoselective asymmetric Michael addition of chiral amine (−)-21 [(1S,2R)-(−)-2-methoxybornyl-10-benzylamine] into the α,β-unsaturated carbonyl moiety of key intermediate 8, thus establishing the second chiral center in (+)-negamycin. 5-epi-Negamycin was also prepared in a similar fashion. 相似文献
994.
The extent of substituent influence on the vertical electron affinities (EAs) and ionization energies (IEs) of 43 substituted tria-, penta-, and heptafulvenes was examined computationally at the OVGF/6-311G(d)//B3LYP/6-311G(d) level of theory and compared with those of tetracyanoquinodimethane (TCNQ) and tetrathiafulvalene (TTF) as representing strong electron-acceptor and -donor compounds, respectively. The substituents X at the exocyclic positions of the fulvenes were either NH(2), H, or CN, while the substituents Y at the ring positions were H, Cl, F, CN, or NH(2). The variations of the EAs and IEs were rationalized by qualitative arguments based on frontier orbital symmetries for the different fulvene classes with either X or Y being constant. The minimum and maximum values found for the calculated EAs of the tria-, penta-, and heptafulvenes were 0.51-2.05, 0.24-3.63, and 0.53-3.14 eV, respectively, and for the IEs 5.27-9.96, 7.07-10.31, and 6.35-10.59 eV, respectively. Two of the investigated fulvenes outperform TCNQ (calcd EA = 2.63 eV) and one outperforms TTF (calcd IE = 6.25 eV) with regard to acceptor and donor abilities, respectively. We also evaluated the properties of bis(fulvene)s, i.e., compounds composed of a donor-type heptafulvene fused with an acceptor-type pentafulvene, and it was revealed that these bis(fulvene)s can be designed so that the IE and EA of the two separate fulvene segments are retained, potentially allowing for the design of compact donor-acceptor dyads. 相似文献
995.
We have analyzed data of the DISTO experiment on the exclusive pp → K ?+? Λp process at T p ?=?2.85 GeV to search for a K ??? pp (?≡?X) nuclear bound state to be formed in the pp → K ?+??+?X reaction. The deviation spectra of the K ?+? missing-mass ΔM (K ?+?) and Λp invariant-mass M(Λp) with selection of large-angle proton emission revealed a structure with M X ?=?2265 ±2 MeV/c 2 and Γ X ?=?118 ±8 MeV. 相似文献
996.
R. Maruyama M. Hino H. Hayashida M. Kitaguchi N. Achiwa D. Yamazaki T. Ebisawa K. Soyama 《Physica B: Condensed Matter》2009,404(17):2594-2599
Neutron resonance spin echo (NRSE) enables us to measure neutron quasi-elastic scattering with high energy resolution. Its energy resolution is limited by a path length variation due to the beam divergence. Neutron focusing technique using a neutron supermirror can be used to overcome this problem. To investigate the effect of a cylindrical mirror on the path length variation due to the beam divergence, MIEZE (modulation of intensity by zero effort) spin echo measurement was performed. The result demonstrated that the cylindrical mirror effectively corrects the path length variation and leads to high energy resolution as well as high intensity in NRSE and MIEZE measurement. 相似文献
997.
Hideo Sagawa Jana Mendrok Takamasa Seta Hiromichi Hoshina Philippe Baron Kodai Suzuki Iwao Hosako Chiko Otani Paul Hartogh Yasuko Kasai 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(18):2027-2036
Carbon dioxide (CO2) induced pressure broadening coefficients of water vapor (H2O) lines have been determined using a terahertz time-domain spectrometer (TDS). Thirty-two rotational transitions of H2O were observed in the spectral range of 18– (550–3050 GHz) for the first time. Using TDS allows one to measure absorption spectra with one order of magnitude better precision than Fourier transform spectrometer in this frequency region. The precision of our broadening coefficient measurements was 2.4% in average. The measured CO2 induced pressure broadening coefficients are compared to those calculated by the complex Robert–Bonamy formalism. The difference between the measurement and the theoretical estimation was in the range of -10.7% to +19.0% confirming the credibility of the theoretical approach. The impact on retrieval of water vapor abundance was examined by performing inversion analysis on H2O spectra of Venus atmosphere obtained with the Submillimeter Wave Astronomy Satellite. In this example case, the retrieved water vapor mixing ratio reduces by half at the altitude region of 70–85 km when applying the newly measured broadening coefficient compared to the air-broadening coefficient, and changes by 5% compared to that estimated by the complex Robert–Bonamy formalism. 相似文献
998.
Masaki Y Yamazaki K Kawai H Yamada T Itoh A Arai Y Furukawa H 《Chemical & pharmaceutical bulletin》2006,54(4):591-593
Polymer-supported dicyanoketene acetal (poly-DCKA-1), synthesized by copolymerization of a DCKA bearing a 4-vinylbenzyl group with ethyleneglycol dimethacrylate, was found to be an excellent recyclable catalyst for the three-component Mannich-type reaction of aldehydes, aromatic amines, and TMS enolate of ethyl isobutyrate in water as the sole solvent. 相似文献
999.
José-Luis Pérez Kazutoshi Yamazaki Xiang Yu 《Journal of Optimization Theory and Applications》2018,179(2):553-568
This paper studies the optimal dividend problem with capital injection under the constraint that the cumulative dividend strategy is absolutely continuous. We consider an open problem of the general spectrally negative case and derive the optimal solution explicitly using the fluctuation identities of the refracted–reflected Lévy process. The optimal strategy as well as the value function is concisely written in terms of the scale function. Numerical results are also provided to confirm the analytical conclusions. 相似文献
1000.
In a liberalized telecommunications market, an incumbent has several advantages over any entrant. An asymmetric access charge regulation for two such asymmetric firms stimulates competitive investment. We show that an entrant with a cost disadvantage has an incentive to invest as a leader under an asymmetric access charge regulation. These results fit well with the findings of previous empirical work. Moreover, we also investigate the effects of an asymmetric access charge regulation on competitive investment strategies. 相似文献