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Osei-Twum EY Litorja LA Darkwa J Maisela LL Lesimple A Mamer O 《Journal of the American Society for Mass Spectrometry》2005,16(1):94-99
The mass spectral behavior of a number of organometallic complexes containing the Group 10 metals Ni, Pd, and Pt, together with various thiolate ligands were studied. For Pd, two main types of complexes, differing by the substituents on the phosphorus atom were studied. Types I and II were substituted with bis(diphenylphosphino)ferrocene and bis(diisopropylphosphino)ferrocene ligands, respectively. The Ni complexes, except for one, and the Pd Type I complexes had no molecular radical cations (M(+.)) in their EI spectra. On the other hand, all the Pt complexes showed intense M(+.) ions in their EI spectra indicating that these complexes were more stable as radical cations than those of Ni and Pd. The FAB and MALDI spectra of all the complexes displayed intense quasi-molecular ions (MH(+)) and the fragmentations in both modes were similar. The MALDI spectra of several complexes displayed only M(+.) ions while one gave evidence of both MH(+) and M(+.) ions. Several Pd Type II complexes yielded intense M(+.) in their EI spectra. 相似文献
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A discussion is given of the relation between the maximum functionaltheorem and Schwinger's variational principle, and it is shownthat the bound given by Schwinger's principle is better thanor the same as that given by the maximum functional theorem. 相似文献
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Van Zandt LL 《Physical review letters》1986,57(16):2085-2087
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Following the variational principles for linear initial valueproblems associated with the wave and heat conduction equationsdiscussed by Gurtin and Leitmann and using time convolutionsit is shown that general variational principles exist for theseproblems with sources on the boundaries and within the regionunder consideration. 相似文献
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Modified Locally One Dimensional Methods for Parabolic Partial Differential Equations in Two Space Variables 总被引:1,自引:0,他引:1
In this note we consider the locally one dimensional methodas discussed in Gourlay & Mitchell (1969, 1972) and indicatehow this scheme can be used to solve accurately a parabolicpartial differential equation in two space variables. 相似文献
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