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71.
72.
Abstract— Exploratory experiments using simulated conditions indicate that the terpene, (+)-limonene can serve to detect O2 (1 Δg ) in polluted atmospheres. 1 O2 attack on limonene results in the formation of specific oxidation products in a specific distribution; quantitative identification of these products is a highly specific test for 1 O2 . 相似文献
73.
Li2H4I2O10, the First Tetrahydrogendimesoperiodate Li2H4I2O10 has been obtained as an intermediate during the dehydration of LiH4IO6 · H2O to LiIO4, for the first time. According to the results of an X-ray structure determination (monoclinic, P21/n, a = 533.98(4), b = 471.85(4), c = 1431.48(10) pm, β = 91.614(7)°, Z = 2, 726 diffractometer data, R = 0.056), Li2H4I2O10 contains the previously unknown tetrahydrogendimesoperiodate ion H4I2O102?, consisting of two edge-shared IO6 octahedra. They are connected with LiO6 octahedra via common edges and vertices. The crystals are non-merohedrally twinned along (100). 相似文献
74.
Abstract— A systematic comprehensive consideration of the emission spectroscopy, emission lifetimes, transient spectroscopy, as well as quantum yields of fluorescence, triplet occupation and photoisomeriz-ation is given for a wide variety of polyene derivatives including retinyl and longer, as well as shorter chainlength homologs. Absorption spectral properties and the results and significance of theoretical calculations are also included. Chainlength, solvent and temperature effects on state order and photophysical as well as photoisomerization properties are evaluated. The mechanism for the primary light step in vision is considered in light of photophysical and photoisomerization data on model visual pigments and rhodopsin. 相似文献
75.
The fitting of highly accurate potential energy points and of the diagonal adiabatic coupling for H3+ using different functional forms is presented. A recently derived analytical potential based on 69 points has been extended to give a highly reliable form of the topology of the surface far beyond the barrier to linearity. Rovibrational frequencies have been derived and are compared with experiment. Detailed information about the experimentally observed rovibrational transitions near 1.25 microm will be given. The computed transition frequencies reproduce experimental transitions within a tenth up to a few hundredths of a wavenumber, if a simulation of non-adiabatic effects is taken into account. 相似文献
76.
B. A. Bushaw H. -J. Kluge J. Lantzsch R. Schwalbach J. Stenner H. Stevens K. Wendt K. Zimmer 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,28(4):275-281
The hyperfine spectra of the 5s4d 3 D 1-5s20f, 5s4d 3 D 2-5s23f, and 5s 4d 3 D 3-5s32f transitions of87Sr (I=9/2) have been measured by collinear fast beam laser spectroscopy. The structure in the upper configurations is highly perturbed by fine structure splitting that is of comparable size to the hyperfine interaction energy. These perturbations can be adequately treated with conventional matrix diagonalization methods, using the 5s-electron magnetic dipole interaction terma 5s and the unperturbed fine structure splittings as input parameters. Additionally, hyperfine constants for the lower 5s4d 3 D configurations, including theA- andB-factors and a separation of the individuals- andd-electron contributions to these factors, are derived. 相似文献
77.
[reaction: see text] The palladium-catalyzed coupling of a range of enol triflates with amides, carbamates, and sulfonamides has been developed. This offers a simple and widely applicable synthesis of enamides, which may not be readily available by other means. 相似文献
78.
Symmetric and asymmetric xanthene dyes have been prepared by a convenient one-step procedure from aldehyde and diol or m-aminophenol precursors using concentrated phosphoric acid as a solvent. This protocol provides access to water-soluble dyes with large Stoke’s shifts and far-red fluorescence emission. These compounds are envisioned as components of fluorescence-based sensors for a variety of imaging applications. 相似文献
79.
A. Breakstone C. D. Buchanan R. Campanini H. B. Crawley M. Cuffiani G. M. Dallavalle M. M. Deninno K. Doroba D. Drijard F. Fabbri A. Firestone H. G. Fischer H. Flöge H. Frehse W. M. Geist L. Gesswein G. Giacomelli R. Gokieli M. Gorbics M. Gorski P. Hanke M. Heiden D. Isenhower E. E. Kluge J. W. Lamsa T. Lohse R. Mankel W. T. Meyer T. Nakada M. Panter A. Putzer K. Rauschnabel B. Rensch F. Rimondi M. Schmelling G. P. Siroli J. Skeens R. Sosnowski M. Szczekowski O. Ullaland D. Wegener R. Yeung 《Zeitschrift fur Physik C Particles and Fields》1991,52(4):551-557
80.