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941.
942.
Burford N Cameron TS Conroy KD Ellis B Lumsden M Macdonald CL McDonald R Phillips AD Ragogna PJ Schurko RW Walsh D Wasylishen RE 《Journal of the American Chemical Society》2002,124(47):14012-14013
Isolation and characterization of a crystal mixture of iminophosphine 1 and diphosphazane 2 (R = Mes*, X = OTf) is enabled by the steric interactions between bulky substituents implicating monomer/dimer 1/2 equilibria and the conclusion is supported by the observation of a ring-expansion reaction to give a triphosphazane 3 (R = Dipp, X = Cl). 相似文献
943.
K. J. Ellis R. J. Shypailo R. Schanler C. Langston M. Finegold 《Journal of Radioanalytical and Nuclear Chemistry》1993,169(2):317-323
Few data exist on the elemental composition of the human body during infancy. The scarcity of the data is due, in part, to the destructive nature of total body analyses normally required for the classical chemical approach. To help determine such data for infants, we have developed a neutron activation facility for nondestructive postmortem analyses. The system consists of a multisource241AmBe irradiator and a multidetector NaI(T1) whole body counter. The total body contents of K, Ca, P, Na and Cl are determined. Postmortem examinations have been performed in twelve infant cadavers. These results are compared with those of the reference fetus. 相似文献
944.
Mass spectra of 3-acetamido-, 3-methoxy-, and 4-methoxy-2-pyridinecarboxylic acids, 2,6-pyridinedicarboxylic acid, 4-nitro-2-pyridinecarboxylic acid N-oxide, 2-chloro- and 2-nitro-x-pyridinecarboxylic acids (X = 3 and 5), 2-chloro- and 2-nitro-4-pyridinecarboxylic acids, and 4-pyridinecarboxylic acid are reported. The 2-pyridinecarboxylic acids lost carbon dioxide (M-44) as has been reported. The 3-pyridinecarboxylic acids showed no definite trend in fragmentation; however, the 4-pyridinecarboxylic acids lost OH (M-17) first. This change in fragmentation pat-tern is due to an interaction of the ring nitrogen and carboxyl group in the 2-pyridinecarboxylic acids which is not present in the 4-pyridinecarboxylic acids. 相似文献
945.
Reduction of several metal carbonyl dimers including Mn2](CO)10, [C5H5Fe(C0)2]2, Co2(CO)8, and [C5H5M(CO)3]2 (M = Cr, Mo and W) by sodium—potassium alloy (NaK) in tetrahydrofuran at room temperature provides a rapid and clean method for the production of the corresponding metal carbonyl anions in high yield. Isolation and characterization of [n-Bu4N] [Fe(CO)2C5H5] from the iron dimer reduction is described. Reductions of other carbonyls including M(CO)6 (M = Cr, Mo and W) and Re2(CO)10 proceed more slowly than previously established methods and provide principally M2(CO)102? and Re(CO)55?. Methods for the preparation of Re(CO)5? are critically considered. The reaction of NaK with [C5H5NiCO]2 is discussed in relation to previously reported results. Infrared solution spectra of a number of carbonyl anions in THF, obtained in a special infrared solution cell, are reported. 相似文献
946.
Nieves Rafael A. Ellis Robert P. Himmel Michael E. 《Applied biochemistry and biotechnology》1990,24(1):397-406
Applied Biochemistry and Biotechnology - 相似文献
947.
Graham Ellis 《Proceedings of the American Mathematical Society》1998,126(9):2513-2523
This paper is based on the seemingly new observation that the Schur multiplier of a -generator group of prime-power order has order . We prove several related results, including sufficient conditions for a sharper bound on to be an equality.
948.
949.
950.