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141.
Nakano M Kishi R Nakagawa N Ohta S Takahashi H Furukawa S Kamada K Ohta K Champagne B Botek E Yamada S Yamaguchi K 《The journal of physical chemistry. A》2006,110(12):4238-4243
The second hyperpolarizabilities of bisimidazole- and bistriazole-benzene compounds have been calculated at different levels of approximation to unravel the effects of diradical character as well as of charge and spin multiplicity. The largest second hyperpolarizabilities are associated with intermediate diradical character, provided positive charging does not compensate for this effect. For the neutral diradical bisimidazole compound, the singlet diradical species possesses a second hyperpolarizability two to three times larger than the corresponding triplet, demonstrating the possibility of spin state control of the third-order NLO responses for diradical species. 相似文献
142.
143.
Adsorption and desorption of atomic hydrogen on single-walled carbon nanotubes were observed by photoluminescence spectroscopy. A satellite peak appeared at the lower energy side of the E11 photoluminescence emission peak after exposure to atomic hydrogen and then disappeared after annealing at 300?°C in vacuum. The energy difference between the satellite peak and E11 peak was 40-80 meV, depending on the tube diameter. The satellite peak was attributed to the triplet dark exciton that became optically active because of the effectively enhanced spin-orbit interaction induced by adsorbed hydrogen atoms. 相似文献
144.
We propose an iterated local search based on several classes of local and large neighborhoods for the bin packing problem with conflicts. This problem, which combines the characteristics of both bin packing and vertex coloring, arises in various application contexts such as logistics and transportation, timetabling, and resource allocation for cloud computing. We introduce \({\mathcal O}(1)\) evaluation procedures for classical local-search moves, polynomial variants of ejection chains and assignment neighborhoods, an adaptive set covering-based neighborhood, and finally a controlled use of 0-cost moves to further diversify the search. The overall method produces solutions of good quality on the classical benchmark instances and scales very well with an increase of problem size. Extensive computational experiments are conducted to measure the respective contribution of each proposed neighborhood. In particular, the 0-cost moves and the large neighborhood based on set covering contribute very significantly to the search. Several research perspectives are open in relation to possible hybridizations with other state-of-the-art mathematical programming heuristics for this problem. 相似文献
145.
Bisubmodular functions are a natural “directed”, or “signed”, extension of submodular functions with several applications.
Recently Fujishige and Iwata showed how to extend the Iwata, Fleischer, and Fujishige (IFF) algorithm for submodular function
minimization (SFM) to bisubmodular function minimization (BSFM). However, they were able to extend only the weakly polynomial
version of IFF to BSFM. Here we investigate the difficulty that prevented them from also extending the strongly polynomial
version of IFF to BSFM, and we show a way around the difficulty. This new method gives a somewhat simpler strongly polynomial
SFM algorithm, as well as the first combinatorial strongly polynomial algorithm for BSFM. This further leads to extending
Iwata’s fully combinatorial version of IFF to BSFM.
The research of S. T. McCormick was supported by an NSERC Operating Grant.
The research of S. Fujishige was supported by a Grant-in-Aid of the Ministry of Education, Culture, Science and Technology
of Japan. 相似文献
146.
Satoru Fukasawa 《Geometriae Dedicata》2010,146(1):9-20
We consider the following problem: For a smooth plane curve C of degree d ≥ 4 in characteristic p > 0, determine the number δ(C) of inner Galois points with respect to C. This problem seems to be open in the case where d ≡ 1 mod p and C is not a Fermat curve F(p
e
+ 1) of degree p
e
+ 1. When p ≠ 2, we completely determine δ(C). If p = 2 (and C is in the open case), then we prove that δ(C) = 0, 1 or d and δ(C) = d only if d−1 is a power of 2, and give an example with δ(C) = d when d = 5. As an application, we characterize a smooth plane curve having both inner and outer Galois points. On the other hand,
for Klein quartic curve with suitable coordinates in characteristic two, we prove that the set of outer Galois points coincides
with the one of
\mathbbF2{\mathbb{F}_{2}} -rational points in
\mathbbP2{\mathbb{P}^{2}}. 相似文献
147.
Ikeda T Fujiyoshi S Kato H Kudo A Onishi H 《The journal of physical chemistry. B》2006,110(15):7883-7886
Electrons photoexcited in K(3)Ta(3)B(2)O(12), an efficient photocatalyst for the water-splitting reaction driven by ultraviolet light, were observed using time-resolved IR absorption spectroscopy with microsecond resolution. When the catalyst was irradiated with 266 nm light pulses, a structureless absorption appeared at 3000-1500 cm(-1). The absorption was assigned to the optical transition of electrons that were band gap-excited and then trapped in mid-gap states. The absorbance decayed with a time delay because of the electron-hole recombination. The rate of recombination in an argon atmosphere was sensitive to the composition of the starting material used in the catalyst preparation. The electron decay was accelerated by exposing the catalyst to water vapor. The degree of acceleration was qualitatively correlated with the H(2) production rate observed during steady-state light irradiation. 相似文献
148.
Sato S Nakamura T Nitobe S Kiba T Hosokawa K Kasajima T Otsuka I Akimoto S Kakuchi T 《The journal of physical chemistry. B》2006,110(43):21444-21449
Dimethylanthracene (DMA), which exhibits almost no self-association in bulk organic solvents, forms a dimer and emits excimer-like fluorescence in a gamma-cyclodextrin nanocavity in a dilute aqueous solution. The 1Bb and 1La electronic transitions of the DMA dimer split by 2230 and 344 cm(-1), respectively, in a fluorescence excitation spectrum obtained with the excimer-like emission. From these energy splits, the structure of dimer in relation to a dielectric constant inside gamma-CD was discussed on the basis of atom-atom Lennard-Jones potential calculations including Coulombic interactions. Excitation relaxations of DMA in the presence of alpha-, beta-, and gamma-CDs in aqueous solutions were investigated by time-resolved fluorescence. The results suggest that both the hydrated and anhydrated species exist in the alpha- and gamma-CD complexes, while only the anhydrated species exists in the beta-CD complex. 相似文献
149.
Takoukam Soh Serge Didier Shinji Tokonami Masahiro Hosoda Takahito Suzuki Hiromi Kudo 《Isotopes in environmental and health studies》2013,49(5):499-510
ABSTRACTRadon, thoron and associated progeny measurements have been carried out in 71 dwellings of Douala city, Cameroon. The radon–thoron discriminative detectors (RADUET) were used to estimate the radon and thoron concentration, while thoron progeny monitors measured equilibrium equivalent thoron concentration (EETC). Radon, thoron and thoron progeny concentrations vary from 31?±?1 to 436?±?12 Bq?m–3, 4?±?7 to 246?±?5 Bq?m–3, and 1.5?±?0.9 to 13.1?±?9.4 Bq?m–3. The mean value of the equilibrium factor for thoron is estimated at 0.11?±?0.16. The annual effective dose due to exposure to indoor radon and progeny ranges from 0.6 to 9?mSv?a–1 with an average value of 2.6?±?0.1?mSv?a–1. The effective dose due to the exposure to thoron and progeny vary from 0.3 to 2.9?mSv?a–1 with an average value of 1.0?±?0.4?mSv?a–1. The contribution of thoron and its progeny to the total inhalation dose ranges from 7 to 60?% with an average value of 26?%; thus their contributions should not be neglected in the inhalation dose assessment. 相似文献
150.
Differential scanning calorimetry (DSC) thermograms, X-ray diffraction (XRD) analysis, electrical conductivity (σ), and 7Li NMR spectroscopy characterization of n-C m H(2m?+?1)COOM solids (M = Li, Na, K; m?=?13, 15, 17, 19, 21) and mixed crystals n-C21H43COOLi x K(1???x) (0.25?≤?x?≤?0.75) was performed as a function of temperature. DSC thermograms of n-C m H(2m?+?1)COOM revealed several solid-solid phase transitions with large entropy changes. Electrical conductivity studies established that n-C m H(2m?+?1)COOLi crystals are poor electrical conductors. In contrast, n-C m H(2m?+?1)COOK salts were found to have σ values of 10???7–10???8 S·cm???1. Since the crystal structures and phase-transition temperatures of both n-C m H(2m?+?1)COOLi and n-C m H(2m?+?1)COOK crystals were similar, they were able to form mixed crystals with the structure n-C x H(2m?+?1)COOLi x K(1???x). DSC thermograms of the mixed crystals showed a small entropy change at the melting point (ΔS mp?<?13 J K???1 mol???1), in addition, large ΔS values at the solid-solid phase transition temperature. The σ values obtained for mixed crystals were roughly one order of magnitude greater than those determined for n-C21H43COOK crystals. 7Li NMR spectra of the mixed crystals recorded at various temperatures suggested that the self-diffusion of Li?+? ions was excited in the highest-temperature solid phase. Based on these results, we have classified these mixed crystals as rotator crystals. 相似文献