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401.
We have experimentally observed and theoretically identified a novel class of purely long-range molecules. This novel purely long-range state is formed due to a very weak hyperfine interaction that is usually treated only as a small perturbation in molecular spectra. Photoassociation spectroscopy of ultracold ytterbium (171Yb) atoms with the 1S0-3P1 intercombination transition presents clear identification of molecular states and the shallowest molecular potential depth of about 750 MHz among the purely long-range molecules ever observed.  相似文献   
402.
403.
The synthesis and properties of (E)-α,β-difluorostilbene derivatives were studied. In particular, we investigated three suppression methods of (E)–(Z) isomerisation by shortening the molecular conjugation length, which included the introduction of a fluorine atom into the ortho or para position of the benzene ring or the replacement of the benzene ring with a cyclohexane ring. The relationship between the molecular structure of liquid crystals and the level of isomerisation by ultraviolet (UV) light was discussed.  相似文献   
404.
The title indolecarboxylate (1) is synthesized as a potential intermediate for the preparation of the central and right parts of CC-1065 (2).  相似文献   
405.
Tachibana  M.  Tojo  T.  Kawaji  H.  Atake  T.  Morita  N.  Ikuta  H.  Uchimoto  Y.  Wakihara  M. 《Journal of Thermal Analysis and Calorimetry》2002,69(3):997-1004
Heat capacity of spinel LiCr1/6Mn11/6O4-d (d=0, 0.0184)was measured between 5 and 300 K. Both compounds showed no anomaly in the measured temperature range, especially around the room temperature where a structural phase transition is reported for the parent compound LiMn2O4. The non-stoichiometric compound LiCr1/6Mn11/6O3.9816 has greater heat capacity than that of the stoichiometric LiCr1/6Mn11/6O4. Molecular dynamics study on the vibrational property of LiMn2O4-d revealed that the lattice defects in the non-stoichiometric compound increase the low frequency phonons compared with the stoichiometric compound. It should be related to the greater heat capacity of the non-stoichiometric compound LiCr1/6Mn11/6O3.9816. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
406.
The irradiation with UV light of a number of 1,2-diaryl-1-tosylstilbenes, in the presence of base, leads to the corresponding phenanthrenes and heterocyclic analogues. These results are consistent with a mechanism involving the base-induced elimination of p-toluenesulfinic acid from an intermediate 9-tosyl-4a,4b-dihydrophenanthrene, formed by photochemical cyclization of the starting 1,2-diaryl-1-tosylstilbenes. [reaction: see text]  相似文献   
407.
Poly(2,7-di-n-pentyldibenzofulvene)s with no stereocenters, obtained by anionic polymerization using chiral 9-fluorenyllithium ligand complexes, showed intense circular dichroism in film form due purely to the chiral conformation of the main chain, while no chiroptical properties were detectable in solution.  相似文献   
408.
Abstract— In an attempt to study the quenching of the triplet state of acetophenone by indole, we have prepared the compounds containing these chromophores intramolecularly. The emission measurements in rigid glasses at 77 K have indicated that the quenching of the triplet acetophenone is due to intramolecular triplet-triplet energy transfer to the indole chromophore, resulting in the sensitization of the indole phosphorescence. The efficiency of the energy transfer has reached ca. 100% in ethanol glasses, while it has been suggested that in methylcyclohexane glasses, the indole chromophore except for 1-methyl derivative is subjected to strong interaction with the acetophenone chromophore other than electronic energy transfer.  相似文献   
409.
Andou T  Endoh T  Mie M  Kobatake E 《The Analyst》2011,136(12):2446-2449
In this study, non-engineered RNAs were detected in living cells using bioluminescence. Two types of probe were utilized: a peptide inserted RLuc (PI-RLuc) probe and a split-RNA probe. Incorporation of the PI-RLuc and split-RNA probes enabled the direct detection of RNA introduced into living cells.  相似文献   
410.
A novel high‐order finite volume scheme using flux correction methods in conjunction with structured finite differences is extended to low Mach and incompressible flows on strand grids. Flux correction achieves a high order by explicitly canceling low‐order truncation error terms across finite volume faces and is applied in unstructured layers of the strand grid. The layers are then coupled together using a source term containing summation‐by‐parts finite differences in the strand direction. A preconditioner is employed to extend the method to low speed and incompressible flows. We further extend the method to turbulent flows with the Spalart–Allmaras model. Laminar flow test cases indicate improvements in accuracy and convergence using the high‐order preconditioned method, while turbulent body‐of‐revolution flow results show improvements in only some cases, perhaps because of dominant errors arising from the turbulence model itself. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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