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41.

The extraction behavior of Nd(III) and Eu(III) with 0.05 mol dm−3 furosemide in benzyl alcohol as single acidic extractant and then with equimolar (0.05 mol dm−3) synergic mixture of furosemide as acidic extractant and tribenzylamine as neutral donor in benzyl alcohol has been studied from aqueous solutions of pH 1 to 6. The effect of various parameters and of various cations and anions on the extraction of these metal ions was investigated. The composition of the extracted adducts was determined by slope analysis method that came out to be [(M(FS)2)+ (CH3COO)] and [M(FS)3·3TBA] where M = Nd(III) and Eu(III).

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The title compound (III) was prepared by reaction of trisethenenickel(0) (II), 2,2-bipyridyl and butadiene at –40°C in the form of dark grey-green crystals with a metallic luster. The structure was determined by X-ray crystallography.
Röntgenstrukturanalyse.  相似文献   
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The structure of delphinifoline, a minor alkaloid of Aconitumdelphinifolium DC, was established by spectroscopic methods, and X-ray crystallography.  相似文献   
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Routes have been developed to the hitherto unobtainable arsine-olefin ligands (CH2CHCH2CH2)nAs(CH2CH2CH2AsMe2)3-n (n = 1, tasol, but-3-enylbis(3-dimethylarsinopropyl)arsine; n = 2, dasdol, 3-dimethylarsinopropylbis(but-3-enyl)arsine) by making use of the difference in reactivity between the ClC and AsCl bonds in the precursor Cl(CH2)mAsCl2 (m = 2,3) molecules. Thus, the triarsine obtained by reaction of 2-chloroethyldichloroarsine with the Grignard reagent of 3-chloropropyldimethylarsine yields 2-chloroethylbis(3-dimethylarsinopropyl)arsine, from which tasol is obtainable by subsequent reaction with either the Grignard reagent of vinyl bromide or, preferably, with vinyllithium. Similarly, 3-chloropropyldichloroarsine reacts with the Grignard reagent of 4-chlorobut-1-ene to form 3-chloropropylbis(but-3-enyl)arsine which, on reaction with sodium dimethylarsenide yields dasdol. The tasol ligand reacts with nickel(II) salts to form [NiX(tasol)]+ (X = Cl, Br) and [NiI2(tasol)], the former are trigonal bipyramidal and contain a nickel(II)—olefin bond, and the latter are square pyramidal containing a [NiI2As3] coordination sphere. In addition, tasol forms a number of polynuclear complexes with nickel(II). The dasdol ligand acts as a bidentate arsine to form only [NiX(dasdol)2)]+ The formation of novel nickel(II)—olefin bonds in the [NiX(tasol)]+ cations is discussed.  相似文献   
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The classical Kähler equation for an inhomogeneous differential form is analysed in some detail with respect to the physical properties of its Minkowski space solutions. Although the components of the field contain only integer representations of the Lorentz group for a physical interpretation of the quantum theory, we impose fermionic commutators. The electromagnetic interactions are identical to those of a Dirac spinor field with an extra fourfold degeneracy. Possibilities for the interpretation of the extra degrees of freedom are discussed.  相似文献   
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