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961.
Yoshihiro Itoh Osamu Yamashita Akira Hachimori Masanobu Kojima Satoshi Suzuki 《Journal of polymer science. Part A, Polymer chemistry》1995,33(1):137-142
Amphiphilic copolymers containing 1-(2-naphthyl)ethyl ester groups were prepared and their fluorescence properties were examined. The fluorescnce spectra of the copolymers with a higher naphthyl content showed predominantly a broad monomer emission with λmax at 340 nm in methanol, whereas a structured emission with λmax at 344 and 362 nm was observed in aqueous solution. The former spectra changed rapidly to the latter ones upon UV irradiation. Photolysis of the copolymers and the monomeric model compound in methanol gave 2-vinylnaphthalene, whose fluorescence agreed with those of copolymers in water, together with methyl ether, alkylnaphthalenes, and other products. These results indicate that the copolymers hold vinylnaphthalene-like traps, which may emit preferentially in water because of efficient sensitization. © 1995 John Wiley & Sons, Inc. 相似文献
962.
Yoshihiro Ohtsuka 《Optical Review》1995,2(5):347-351
This paper describes invariance of the normalized optical spectrum for a particular class of optical fields propagated in the far zone from a secondary, spatially, partially coherent source. The optical field across the secondary planar source is inhomogeneous to give the complex degree of spectral coherence such that μ = h(αω(ρ1–ρ2))exp(iɛω(ρ12–ρ22)), where α, ɛ are constants, ω is optical frequency, and ρ1, ρ2 denote two points in the secondary source. This expression for μ is the same as obtained in the Fresnel zone from a primary, spatially incoherent source. The invariance law does not hold for the spectrum of the light propagated from the primary source. 相似文献
963.
964.
Hatakeyama T Okada Y Yoshimoto Y Nakamura M 《Angewandte Chemie (International ed. in English)》2011,50(46):10973-10976
965.
966.
Maeda H Eifuku N Haketa Y Ito Y Lee E Lee M 《Physical chemistry chemical physics : PCCP》2011,13(9):3843-3850
Wedge-shaped amphiphilic derivatives of 1,3-dipyrrolyl-1,3-propanedione boron complexes, with one or no aliphatic chains attached at one aryl moiety and three hydrophilic chains at the other, exhibited formation of assembled structures in aqueous solutions. UV/vis, fluorescence and DLS analyses suggested that the wedge-shaped amphiphiles exist in assembled modes in the solution state, and TEM measurements revealed that a balance of hydrophobic and hydrophilic moieties in the amphiphiles is crucial for the formation of organized structures in aqueous solutions as evidenced by the formation of spherical and cylindrical micelles. 相似文献
967.
Kubozono Y Mitamura H Lee X He X Yamanari Y Takahashi Y Suzuki Y Kaji Y Eguchi R Akaike K Kambe T Okamoto H Fujiwara A Kato T Kosugi T Aoki H 《Physical chemistry chemical physics : PCCP》2011,13(37):16476-16493
New carbon-based superconductors are synthesized by intercalating metal atoms into the solid-phase hydrocarbons picene and coronene. The highest reported superconducting transition temperature, T(c), of a hydrocarbon superconductor is 18 K for K(3)picene. The physics and chemistry of the hydrocarbon superconductors are extensively described for A(x)picene (A: alkali and alkali earth-metal atoms) for x = 0-5. The theoretical picture of their electronic structure is also reviewed. Future prospects for hydrocarbon superconductors are discussed from the viewpoint of combining electronics with condensed-matter physics: modification of the physical properties of hydrocarbon solids is explored by building them into a field-effect transistor. The features of other carbon-based superconductors are compared to clarify the nature of hydrocarbon superconductors. 相似文献
968.
Sekine M Oeda Y Iijima Y Taguchi H Ohkubo A Seio K 《Organic & biomolecular chemistry》2011,9(1):210-218
2'-O-(1-Naphthyl)uridine and 2'-O-(2-naphthyl)uridine were synthesized by a microwave-mediated reaction of 2,2'-anhydrouridine with naphthols. Using the 3'-phosphoramidite building blocks, these 2'-O-aryluridine derivatives were incorporated into 2'-O-methylated oligoribonucleotides. Incorporation of five 2'-O-(2-naphthyl)uridines into a 2'-O-methylated RNA sense strand significantly increased the thermostability of the duplex with a 2'-O-methylated RNA antisense strand. Circular dichroism spectroscopy and molecular dynamic simulation of the duplexes formed between the modified RNAs and 2'-O-methyl RNAs suggested that there are π-π interactions between two neighboring naphthyl groups in a sequence of the five consecutively modified nucleosides. 相似文献
969.
Ikeda A Kawai Y Kikuchi J Akiyama M Nakata E Uto Y Hori H 《Organic & biomolecular chemistry》2011,9(8):2622-2627
The fullerene-exchange reaction from a cyclodextrin cavity to liposomes represents one of the best methods to prepare lipid membrane-incorporated [70]fullerenes (C(70)). The C(70)-exchange reaction occurred completely at temperatures above the phase transition temperature (T(m)) of the liposomes; however, lowering the temperature to below the T(m) led to C(70) aggregation outside the liposomes. This observation has limited the development of more functional LMIC(70) using a variety of liposome compositions. In this paper, this reaction was found to occur efficiently by the addition of small amounts of lipids bearing a π-moiety. The π-moieties act as a gate when hydrophobic C(70) migrates into the hydrophilic liposome surface. Therefore, the π-moieties should exist in the polar head groups of the lipids and the C(70)-exchange reaction can be controlled by pH. 相似文献
970.
Flores JA Kobayashi Y Dias HV 《Dalton transactions (Cambridge, England : 2003)》2011,40(40):10351-10359
Halogenated 1,3,5-triazapentadienyl ligands [N{(C(3)F(7))C(C(6)F(5))N}(2)](-), [N{(CF(3))C(C(6)F(5))N}(2)](-) and [N{(C(3)F(7))C(2,6-Cl(2)C(6)H(3))N}(2)](-), alone or in combination with other N-donors like CH(3)CN, CH(3)(CH(2))(2)CN, and N(C(2)H(5))(3), have been used in the stabilization of thermally stable, two-, three- or four-coordinate silver(i) adducts. X-Ray crystallographic analyses of {[N{(C(3)F(7))C(C(6)F(5))N}(2)]Ag}(n), {[N{(C(3)F(7))C(C(6)F(5))N}(2)]Ag(NCCH(3))}(n), {[N{(C(3)F(7))C(2,6-Cl(2)C(6)H(3))N}(2)]Ag(NCCH(3))}(n), {[N{(CF(3))C(C(6)F(5))N}(2)]Ag(NCCH(3))(2)}(n) and {[N{(C(3)F(7))C(C(6)F(5))N}(2)]Ag(NCC(3)H(7))}(n) revealed the presence of bridging 1,3,5-triazapentadienyl ligands bonded to silver through terminal nitrogen atoms. These adducts are polymeric in the solid state. [N{(C(3)F(7))C(2,6-Cl(2)C(6)H(3))N}(2)]AgN(C(2)H(5))(3) is monomeric and features a 1,3,5-triazapentadienyl ligand bonded to Ag(I) in a κ(1)-fashion via only one of the terminal nitrogen atoms. The solid state structure of [N{(C(3)F(7))C(C(6)F(5))N}(2)]H has also been reported and it forms polymeric chains via inter-molecular N-H···N hydrogen-bonding. 相似文献