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71.
Takayoshi Amano 《Journal of Molecular Spectroscopy》1981,88(1):194-206
The Stark effect of the 22 ← 21(E1), 21 ← 30(E1) microwave transitions in the ground state and the 22 ← 21(E1) microwave transition in the first excited CO stretching vibrational state are measured by means of infrared-microwave double resonance with the qQ1(2)E1 infrared transition as the pump transition in the range of 1000 to 2300 V/cm. The dipole moments μa and μb as well as the off-diagonal rotational constant Dab are determined for both the ground and the excited states. The frequency of the qQ1(2)E1 infrared transition is found to be lower by 128 ± 2 MHz than that of the P(34) CO2 laser. 相似文献
72.
Takayoshi Amano 《Journal of Molecular Spectroscopy》1984,103(2):436-454
The fundamental vibration rotation bands of OH and OD have been observed with an estimated accuracy of 0.001 cm?1. Simultaneous fits of the infrared and microwave data are performed to improve the molecular constants in the v = 0 and v = 1 states. The correlated parameters γv and AD are determined by combining the data for OH and OD. Some discussion is presented on the correlated molecular parameters. 相似文献
73.
Liu SQ Kuroda-Sowa T Konaka H Suenaga Y Maekawa M Mizutani T Ning GL Munakata M 《Inorganic chemistry》2005,44(4):1031-1036
Three luminescent silver(I)-oligo(phenylenevinylene) complexes, [Ag2(bmsb)(ClO4)2] (1), [Ag2(bmsb)(H2O)4](BF4)2 (2), and [Ag2(bdb)(CF3SO3)2] (3) (bmsb = 1, 4-bis(methylstyryl)benzene, bdb = 4,4'-bis(2, 5-dimethylstryryl)biphenyl), have been synthesized and structurally characterized. Complexes 1 and 2 are 2D networks with unique metallocyclophane motifs. Complex 3 affords a 2D zigzag sheet, in which silver triflates form tubelike double chains and bdb molecules act as linkages. Complex 2 exhibits high electric conductivity because of columnar aromatic stackings formed through intra- and intermolecular pi-pi interactions. Complexes 1-3 in the solid state exhibit luminescence, of which excitation and emission maxima are shifted to longer wavelength as compared to those of the corresponding metal-free ligands. 相似文献
74.
75.
Tolerance, bioaccumulation, biotransformation and excretion of arsenic compounds by the fresh–water shrimp (Neocaridina denticulata) and the killifish (Oryzias latipes) (collected from the natural environment) were investigated. Tolerances (LC50) of the shrimp against disodium arsenate [abbreviated as As(V)], methylarsonic acid (MAA), dimethylarsinic acid (DMAA), and arsenobetaine (AB) were 1.5, 10, 40, and 150μg As ml?1, respectively. N. denticulata accumulated arsenic from an aqueous phase containing 1 μg As ml?1 of As(V), 10 μg As ml?1 of MAA, 30 μg As ml?1 of DMAA or 150 μg As ml?1 of AB, and biotransformed and excreted part of these species. Both methylation and demethylation of the arsenicals were observed in vivo. When living N. denticulata accumulating arsenic was transferred into an arsenic–free medium, a part of the accumulated arsenic was excreted. The concentration of methylated arsenicals relative to total arsenic was higher in the excrement than in the organism. Total arsenic accumulation in each species via food in the food chain Green algae (Chlorella vulgaris) → shrimp (N. denticulata) → killifish (O. latipes) decreased by one order of magnitude or more, and the concentration of methylated arsenic relative to total arsenic accumulated increased successively with elevation in the trophic level. Only trace amounts of monomethylarsenic species were detected in the shrimp and fish tested. Dimethylarsenic species in alga and shrimp, and trimethylarsenic species in killifish, were the predominant methylated arsenic species, respectively. 相似文献
76.
Maekawa M Kitagawa S Kuroda-Sowa T Munakata M 《Chemical communications (Cambridge, England)》2006,(20):2161-2163
A series of sandwich-shaped complexes based on two square tetranuclear Ag(I) metallomacrocycles, [[Ag4(pprd)4]2(XF6)]-(BF4)6.8MeNO2 (pprd = 4-(2-pyridyl)pyrimidine; X = Si, Ge and Sn), in which a XF6(2-) anion is encapsulated, were prepared and their structures were characterized both in the solid state and solution. 相似文献
77.
We prove the maximal L
ρ regularity of the Cauchy problem of the heat equation in the Besov space
[(B)\dot]1,r0(\mathbbRn){\dot{B}_{1,\rho}^0(\mathbb{R}^n)}, 1 < ρ ≤ ∞, which is not UMD space. And as its application, we establish the time local well-posedness of the solution of two dimensional
nonlinear parabolic system with the Poisson equation in
[(B)\dot]1,20(\mathbbR2){\dot{B}_{1,2}^0(\mathbb{R}^2)} , where the equation is considered in the space invariant by a scaling and particularly the natural free energy is well defined
from the initial time. The small data global existence is also obtained in the same class. 相似文献
78.
An abstract version of Besov spaces is introduced by using the resolvent of nonnegative operators. Interpolation inequalities with respect to abstract Besov spaces and generalized Lorentz spaces are obtained. These inequalities provide a generalization of Sobolev inequalities of logarithmic type. Uniqueness problems to abstract semilinear evolution equations are also discussed (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
79.
An experimental way of testing Bose-Einstein condensation of alpha clusters in the atomic nucleus is reported. The enhancement of cluster emission and the multiplicity partition of possible emitted clusters could be direct signatures for the condensed states. The barrier for the emission of clusters, such as (8)Be and (12)C(O(+)(2)), is calculated and compared with the barrier for the sequential emission of 2 or 3alpha particles from the compound nucleus. For the calculations, a simple approach using a folded Woods-Saxon potential is used. 相似文献
80.
Juri Takayoshi Yong-Lin Huang Yosuke Matsuo Yoshinori Saito Dian-Peng Li Takashi Tanaka 《Molecules (Basel, Switzerland)》2021,26(14)
Ellagitannins (ETs) are plant polyphenols with various health benefits. Recent studies have indicated that the biological activities of ETs are attributable to their degradation products, including ellagic acid and its gut microflora metabolites, such as urolithins. Insect tea produced in the Guangxi region, China, is made from the frass of moth larvae that feed on the ET-rich leaves of Platycarya strobilacea. Chromatographic separation of the Guangxi insect tea showed that the major phenolic constituents are ellagic acid, brevifolin carboxylic acid, gallic acid, brevifolin, and polymeric polyphenols. Chemical investigation of the feed of the larvae, the fresh leaves of P. strobilacea, showed that the major polyphenols are ETs including pedunculagin, casuarictin, strictinin, and a new ET named platycaryanin E. The new ET was confirmed as a dimer of strictinin having a tergalloyl group. The insect tea and the leaves of P. strobilacea contained polymeric polyphenols, both of which were shown to be composed of ETs and proanthocyanidins by acid hydrolysis and thiol degradation. This study clarified that Guangxi insect tea contains ET metabolites produced in the digestive tract of moth larvae, and the metabolites probably have higher bioavailabilities than the original large-molecular ETs of the leaves of P. strobilacea. 相似文献