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31.
Peter Beiersdorfer Natalie Hell Dmytro Panchenko Greg V. Brown Elmar Träbert Richard L. Kelley Caroline A. Kilbourne F. Scott Porter 《X射线光谱测定》2020,49(1):21-24
We report a measurement of the two X-ray transitions that proceed from the and (1s22s1/22p63p1/2)J = 1 upper levels to the (1s22s22p6)J = 0 ground level in neonlike Eu53+ (Z = 63), that is, near the previously documented avoided crossing of the two upper levels at Z = 68. The measurement was carried out using the calorimeter spectrometer on the Livermore EBIT-I electron beam ion trap. It affirms the trends set by the neighboring neonlike ions both in terms of the relative intensity of the two lines and in terms of the magnitude of disagreement with theoretical energy level predictions. 相似文献
32.
We introduce a simple new technique which allows us to solve several problems that can be formulated as seeking a suitable orientation of a given undirected graph. In particular, we use this technique to recognize and transitively orient comparability graphs, to recognize and represent proper circular arc graphs, and to recognize and represent proper interval graphs. As a consequence, we derive and represent proper interval graphs. As a consequence, we derive simple new proofs of a theorem of Ghouila-Houri and a theorem of Skrien. Our algorithms are conceptually simpler than (and often of comparable efficiency to) the existing algorithms for these problems. © 1995 John Wiley & Sons, Inc. 相似文献
33.
Anna Edelsbacher Ernst Urban Waltraud Weidenauer 《Monatshefte für Chemie / Chemical Monthly》1992,123(8-9):741-747
Summary Optically pure available lactones1 and5 were diastereoselectively oxidised tocis-diols2 and6 by KMnO4 and to epoxides3 and7 by 3-chloroperoxybenzoic acid. Epoxide3 was cleaved totrans-diol4, whereas hydrolysis of7 afforded tricyclic carboxylic acid8. Optic ally puredihydroxylactones2,4, and6 are valuable models for structure determination of the antimicrobial garlic component garlicin.
Synthese enantiomerenreiner 5,6-Dihydroxy-isobenzofuranone und 5,6-Dihydroxy-4,7-methano-isobenzofuranone
Zusammenfassung Die in enatiomerenreiner Form verfügbaren Lactone1 und5 wurden durch diastereoselektive Oxidation mit KMnO4 zu dencis-Diolen2 und6 bzw. mit 3-Chlorperoxybenzoesäure zu den Epoxiden3 und7 umgesetzt. Das Epoxid3 liefert bei der Hydrolyse dastrans-Diol4, während aus7 die tricyclische Carbonsäure8 entsteht. Die optisch reinen Dihydroxylactone2,4 und6 können als Vergleichssubstanzen zur Strukturaufklärung des antimikrobiellen Knoblauchinhaltsstoffes Garlicin dienen.相似文献
34.
We measure the point-spread function in the two main configurations of 4Pi confocal microscopy as well as in the traditional confocal arrangement and derive the optical transfer functions from the experimental data. The optical transfer functions are in good agreement with their theoretical counterparts. We find a 3.5- to 5-fold increased axial bandwidth of the 4Pi confocal microscope and hence confirm the enhanced spatial-frequency content of 4Pi images. 相似文献
35.
Martin Bröring Prof. Dr. Christian Hell Melanie Steiner Carsten D. Brandt 《无机化学与普通化学杂志》2007,633(7):1082-1086
A set of porphyrinoid manganese(IV) complexes with the 2,3,7,8,12,13,17,18‐octaethyl‐5,15‐di‐p‐tolylcorrolato ligand [(oedtc)MnIVX] (X = Cl, Br, I) was prepared by oxidation of a manganese(III) precursor. The most unexpected complex in this series, [(oedtc)MnIVI], was found to display significant thermal stability despite the unusual MnIV‐I bond and could be investigated by X‐ray diffraction. Attempted ligand exchange reactions of the chlorido derivative with the pseudohalide anions cyanide, azide, cyanate and thiocyanate yielded the desired [(oedtc)MnIVX] complex only as the isothiocyanate derivative while for the other species the reduction to manganese(III) was observed. 相似文献
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37.
A versatile method was developed to the dealkoxycarbonylation of sterically crowded cyclopropanecarboxylic acid derivatives via a nonhydrolytic ester cleavage followed by a Barton-type decarboxylation. 相似文献
38.
G. Hell Cie. 《Fresenius' Journal of Analytical Chemistry》1884,23(1):590
Ohne Zusammenfassung 相似文献
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