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81.
82.
The 2,3,4,4a,5,6-hexahydro-1H-benzofuro[3,2-e]isoquinoline-7(7aH)-one ring system is prepared from a 4-arylpyridine precursor by sequentil intramolecular enolate addition to a pyridinium ion, Dieckmann cyclization, and catalytic hydrogenation.  相似文献   
83.
The ν2 band of 14N16O2 near 13.3 μm has been measured under high resolution using a vacuum grating spectrograph equipped with a liquid helium cooled Ge:Cu detector. Over 750 transitions were identified. Analysis of the band, combined with previous work at shorter wavelengths, led to modified constants for the ground state, (0, 0, 0), and new values for the constants of the upper state, (0, 1, 0). The new constants reproduced 272 nonzero-weighted transitions with a standard deviation of 0.011 cm?1 and reproduced 346 ground state combination differences with a standard deviation of 0.010 cm?1. The spin-rotation line splittings which were observed were described satisfactorily using existing formulations.  相似文献   
84.
Ohne Zusammenfassung
Book reviews

Notices bibliographiques
  相似文献   
85.
A methodology has been developed to chromatographically quantify indium in polymetallic (bio)hydrometallurgical processing solutions using the Dionex IonPac CS5A column and pyridine‐2,6‐dicarboxylic acid eluent. Cu(II) and In(III) could be separated by elevating the column temperature to 45°C. The comparatively low stability constant of the In‐eluent complex (log K2 = 3.8) required typical leaching samples to be diluted in the eluent rather than acid or water to overcome ligand competition between components of the sample solution and the eluent. The methodology was applied to leachates from (bio)hydrometallurgical processing of oxidic flue dust residues and sulfidic zinc ores, where both are promising candidates for the recovery of indium from low grade ores and metallurgical wastes. Indium, ferrous iron, ferric iron, copper, zinc, nickel, and manganese concentrations could be simultaneously quantified. The method was found suitable for samples containing at least 0.25 mg/L indium and an iron to indium ratio of up to 100:1.  相似文献   
86.
A new program of Compton scattering on deuterium is under way at the tagged-photon facility at MAX-Lab in Lund, Sweden. We will measure differential cross sections between 60° and 150° over the photon energy range 60–115?MeV in 5?MeV steps, with the ultimate goal of obtaining new precision information on the electric and magnetic polarizabilities of the neutron.  相似文献   
87.
Preparation of 1,3-Diketones and of Nitro-diketones by (1:1)-Acylation of Lithium Enolates with Acyl Chlorides Slow addition of precooled solutions of lithium enolates in THF (Fig. 1) to solutions of equimolar amounts of acyl chlorides in the same solvent at temperatures between ? 80 and ? 100° furnishes 1, 3-diketones in acceptable to good yields (Tables 1?3). Even 3-nitropropionyl and 4-nitrobutyryl chloride can be employed for the (1:1)-acylation of enolates to give the synthetically useful 5- and 6-nitro-1, 3-diketones 13 and 25 , respectively. The scope and the limitations of this method of preparing 1, 3-diketones are given and are compared with alternative methods.  相似文献   
88.
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90.
The hydroxyhydrido salt [Rh(6)(P(i)Pr(3))(6)H(11)(OH)][BArF(4)](2) results from the addition of water to [Rh(6)(P(i)Pr(3))(6)H(12)][BArF(4)](2). This reaction is reversible, and the addition of dihydrogen to [Rh(6)(P(i)Pr(3))(6)H(11)(OH)][BArF(4)](2) results in the elimination of water and the regeneration of the hydride cluster.  相似文献   
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