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131.
132.
Fukui H Kishi R Minami T Nagai H Takahashi H Kubo T Kamada K Ohta K Champagne B Botek E Nakano M 《The journal of physical chemistry. A》2008,112(36):8423-8429
Hybrid density functional theory method is applied for investigating the diradical character dependence of the second hyperpolarizability (gamma) of square planar nickel complexes involving several types of bidentate ligands [o-C6H4XY, where X = Y = O, NH, S, Se, and PH as well as (X, Y) = (NH, NH2) and (S, NH2)]. It is found that, as a function of the donor atoms, the diradical character of these complexes varies from 0.0 to 0.884 and is associated with substantial variations of gamma ranging from 14 x 10(3) to 819 x 10(3) au. In particular, the largest gamma values are associated with intermediate diradical characters in good agreement with the structure-property relationship obtained for pure hydrocarbon systems. Increasing the electronegativity of the X and Y donor groups of the ligands leads to larger diradical characters as a result of the enhancement of the double bond nature of the C=X(Y) bonds, which further stabilizes the diradicals on both-end benzene rings. This demonstrates that the electronegativities of the donor atoms of the ligands become a tuning parameter of the diradical character and then of the gamma values of these complexes. 相似文献
133.
The mixed catalyst system, Pd(CH3CN)2Cl2/P(t-Bu)3/[Ru(2,2'-bipyridine)3].2PF6, promotes the copper-free Sonogashira coupling reaction of aryl bromides at room temperature under irradiation of visible light. 相似文献
134.
To prepare sulfur-containing natural polymers effectively, several plant oils and 3,3'-thiodipropionic acid (TDP) have been used as carbon sources for the biosynthesis of copolymer poly[(3-hydroxybutyrate)-co-(3-mercaptopropionate)] [poly(3HB-co-3MP)] by a wild-type bacterium Cupriviadus necator H16. By using the plant oils, copolymer accumulation and incorporation of 3MP units are greater than those of cases using sugars. The 3MP fraction is controllable over a range of 1-39 mol-% by adjusting the cultivation conditions. Microbial degradability of the copolymers has been examined in an activated sludge supernatant. The biodegradation proceeded by two mechanisms: surface erosion and auto-catalytic hydrolysis, depending on the 3MP unit fraction, and show preferential degradation of 3HB unit sequences. 相似文献
135.
Saito Y Bag SS Kusakabe Y Nagai C Matsumoto K Mizuno E Kodate S Suzuka I Saito I 《Chemical communications (Cambridge, England)》2007,(21):2133-2135
A novel FRET based strategy for DNA sequence analysis utilising base-discriminating fluorescence (BDF) nucleoside, (Py)U/(2-Ant)U, as donor in the dual-labelled oligonucleotide probe is reported; a selective/specific emission from acceptor, was observed upon excitation at the donor, only when the opposite base of the "smart" fluorescently labeled BDF nucleoside, (Py)U/(2-Ant)U, is adenine on the complementary target sequence. 相似文献
136.
Yasuhiro Tanoue Akari Hara Norihisa Kai Kazunori Sakata Mamoru Hashimoto Takeshi Nagai 《Journal of heterocyclic chemistry》2007,44(5):1135-1137
137.
Takanori Kiyokura Fumihiko MAEDA Yoshio Watanabe Yoshinori Iketaki Koumei Nagai Yoshiaki Horikawa Masaharu Oshima Eiji Shigemasa Akira Yagishita 《Optical Review》2000,7(6):576-578
The throughput of a Schwarzschild objective using undulator synchrotron radiation was measured. Conventionally, the throughput was estimated from the squared reflectivity of one multilayer mirror and from the obstruction ratio. However, we evaluated the transmission ratio from the input and output photon flux using a precisely calibrated monochromatic beam from an undulator light source. It was found that the objective has a maximum throughput of 8.5% at a wavelength of 13.9 nm. 相似文献
138.
Z B Zheng S Nagai N Iwanami A Kobayashi S Natori U Sankawa 《Chemical & pharmaceutical bulletin》1999,47(6):777-782
Twelve analogues of the antibacterial phenolic peptide 5-S-glutathionyl-N-beta-alanyl-L-dopa (5-S-GA-L-D, 1) were synthesized via orthoquinone using tyrosinase. Several synthesized compounds inhibited the v-Src autophosphorylation tyrosine kinase reaction with an IC50 value comparable to that of herbimycin A. The inhibition of c-Src substrate phosphorylation was much less active than v-Src autophosphorylation inhibition. 5-S-GA-L-D (1) and its analogous competed with peptide substrate and non-compared with ATP. The analogues showed no effects on substrate phosphorylation by epidermal growth factor receptor (EGFR), and this selectivity is the most characteristic feature of the 5-S-GA-L-D and its analogues (1-12). 相似文献
139.
S. V. Dixon‐Garrett K. Nagai B. D. Freeman 《Journal of Polymer Science.Polymer Physics》2000,38(11):1461-1473
The pure‐gas sorption, diffusion, and permeation properties of ethylbenzene in poly(dimethylsiloxane) (PDMS) are reported at 35, 45, and 55 °C and at pressures ranging from 0 to 4.4 cmHg. Additionally, mixed‐gas ethylbenzene/N2 permeability properties at 35 °C, a total feed pressure of 10 atm, and a permeate pressure of 1 atm are reported. Ethylbenzene solubility increases with increasing penetrant relative pressure and can be described by the Flory–Rehner model with an interaction parameter of 0.24 ± 0.02. At a fixed relative pressure, ethylbenzene solubility decreases with increasing temperature, and the enthalpy of sorption is −41.4 ± 0.3 kJ/mol, which is independent of ethylbenzene concentration and essentially equal to the enthalpy of condensation of pure ethylbenzene. Ethylbenzene diffusion coefficients decrease with increasing concentration at 35 °C. The activation energy of ethylbenzene diffusion in PDMS at infinite dilution is 49 ± 6 kJ/mol. The ethylbenzene activation energies of permeation decrease from near 0 to −34 ± 7 kJ/mol as concentration increases, whereas the activation energy of permeation for pure N2 is 8 ± 2 kJ/mol. At 35 °C, ethylbenzene and N2 permeability coefficients determined from pure‐gas permeation experiments are similar to those obtained from mixed‐gas permeation experiments, and ethylbenzene/N2 selectivity values as high as 800 were observed. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1461–1473, 2000 相似文献
140.
Akon Higuchi Tomoya Yoshida Takeshi Imizu Keishin Mizoguchi Zhenjie He Ingo Pinnau Kazukiyo Nagai Benny D. Freeman 《Journal of Polymer Science.Polymer Physics》2000,38(13):1749-1755
Homogeneously fullerene‐dispersed membranes were prepared under the conditions in which a 10 wt % poly(1‐trimethylsilyl‐1‐propyne) solution containing 0.5 wt % fullerene was dried under a reduced pressure of 50 cmHg at 100 °C. UV‐vis spectra and microscopic observations of the fullerene membranes indicated that the fullerene was homogeneously dispersed in the membranes. The permeability coefficients of 1‐butene were found to be higher than those of n‐butane in the fullerene membranes, although the permeability coefficients of olefin gases were nearly equal to those of paraffin gases having the same number of carbon in poly(1‐trimethylsilyl‐1‐propyne) membranes containing no fullerene. Pressure dependence of permeability coefficients was clearly observed for the permeation of carbon dioxide, ethylene, ethane, 1‐butene, and n‐butane through the fullerene membranes, while no significant dependence was found for poly(1‐trimethylsilyl‐1‐propyne) membranes except for the permeation of 1‐butene and n‐butane. The pressure dependence of the permeability was explained by the dual‐mode sorption model. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1749–1755, 2000 相似文献