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Douglas X. West Christopher E. Ooms Jill S. Saleda H. Gebremedhin Anthony E. Liberta 《Transition Metal Chemistry》1994,19(5):553-558
Summary Copper(II) and nickel(II) complexes of 2-formylpyridine 3-piperidinyl-, 3-hexamethyleneiminyl- and 3-azabicyclo-[3.2.2]nonylthiosemicarbazones were prepared and characterized spectroscopically. 1H and 13C n.m.r. spectra of the thiosemicarbazones and a diamagnetic nickel(II) complex are reported, together with i.r., electronic and e.s.r. spectra of the metal complexes. The thiosemicarbazones and their copper(II) and nickel(II) complexes exhibit considerable growth inhibitory activity against Paecilomyces variotii, but show minimal activity against Aspergillus niger. 相似文献
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Douglas X. West Haileselassie Gebremedhin Timothy J. Romack Anthony E. Liberta 《Transition Metal Chemistry》1994,19(4):426-431
Summary Copper(II) complexes of a large number of 2-acetylpyridine 4N-alkyl thiosemicarbazones were prepared and characterized. I.r., electronic and e.s.r. spectra of the complexes, as well as 1H and 13C n.m.r. spectra of the thiosemicarbazones, were obtained. Both the thiosemicarbazones and their complexes show either modest or no growth inhibitory activity against Aspergillus niger, but many have considerable activity against Paecilomyces variotii. There is a relationship between the antifungal activity and size of the 4N-substituent for both the thiosemicarbazones and their copper(II) complexes. 相似文献
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Douglas X. West Haileselassie Gebremedhin Ray J. Butcher Jerry P. Jasinski 《Transition Metal Chemistry》1995,20(1):84-87
Summary The anion (loss of3
N hydrogen) of 2-acetylpyridine4
N-methylthiosemicarbazone coordinates in a planar conformation to copper(II) through the pyridyl nitrogen, azomethine nitrogen and thiolato sulphur atoms. The fourth coordination site is occupied by a bromo ligand and the complex is mononuclear and essentially planar. Bond distances and angles, as well as solid state and solution spectral properties, are compared to other recently reported copper(II) thiosemicarbazone complexes. 相似文献
4.
Douglas X. West Authrine C. Whyte Fatimah D. Sharif Haileselassie Gebremedhin Anthony E. Liberta 《Transition Metal Chemistry》1993,18(2):238-242
Summary NiII and CuII complexes of 2-acetylpyridine 4
N-(2-methylpyridinyl)-, 4
N-(2-ethylpyridinyl)- and 4
N-methyl(2-ethylpyridinyl) thiosemicarbazones (HL4pam, HL4pae, and HL4Mpae, respectively) of general formula [M(HL)X2] have been isolated from boiling EtOH and characterized by physico-chemical and spectroscopic methods. The growth inhibition activities of the thiosemicarbazones and their complexes were measured against Aspergillus nicer and Paecilomyces variotii. 相似文献
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We revisit an algorithm [called Edge Pushing (EP)] for computing Hessians using Automatic Differentiation (AD) recently proposed by Gower and Mello (Optim Methods Softw 27(2): 233–249, 2012). Here we give a new, simpler derivation for the EP algorithm based on the notion of live variables from data-flow analysis in compiler theory and redesign the algorithm with close attention to general applicability and performance. We call this algorithm Livarh and develop an extension of Livarh that incorporates preaccumulation to further reduce execution time—the resulting algorithm is called Livarhacc. We engineer robust implementations for both algorithms Livarh and Livarhacc within ADOL-C, a widely-used operator overloading based AD software tool. Rigorous complexity analyses for the algorithms are provided, and the performance of the algorithms is evaluated using a mesh optimization application and several kinds of synthetic functions as testbeds. The results show that the new algorithms outperform state-of-the-art sparse methods (based on sparsity pattern detection, coloring, compressed matrix evaluation, and recovery) in some cases by orders of magnitude. We have made our implementation available online as open-source software and it will be included in a future release of ADOL-C. 相似文献
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Daniel Gebremedhin Charles Weatherford 《International journal of quantum chemistry》2013,113(1):71-75
The radial Slater‐type orbitals (STO) ${r^\mu }{e^{ - \alpha r}}$ can be simply obtained by repeated parametric differentiation of the Yukawa Potential $({e^{ - \alpha r}}/r)$ with respect to α. A new compact two‐range addition theorem (AdT) for the STO is herein derived by explicit parametric differentiation of the well‐known Yukawa AdT. The resulting addition formula is combined with the single‐range AdT for solid spherical harmonics $({r^l}Y_l^m(\hat r))$ to present a new AdT for three‐dimensional spherical coordinate STOs. We advance the proposition that this formula is “canonical” in the same sense that the Laplace expansion of the Coulomb potential is considered canonical. We demonstrate how this procedure can be employed for all exponential‐type orbitals. © 2012 Wiley Periodicals, Inc. 相似文献
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Cecilia Maichle Alfonso Castineiras Rosa Carballo Haileselassie Gebremedhin Mark A. Lockwood Christopher E. Ooms Timothy J. Romack Douglas X. West 《Transition Metal Chemistry》1995,20(3):228-233
Summary Cobalt(III) complexes of 2-acetylpyridine 3-pyrrolidinyl-,3-piperidinyl-, 3-hexamethyleneiminyl- and 3-azabicyclo-[3.2.2]nonylthiosemicarbazone, [Co(Lpo)2]BF4, [Co-(Lpip)2]BF4, [Co(Lhexim)2]BF4 and [Co(Lbcn)2]BF4, respectively; 2-formylpyridine 3-piperidinyl-, 3-hexa-methyleneiminyl- and 3-azabicyclo[3.2.2]nonylthiosemi-carbazone, [Co(pip)2]BF4, [Co(hexim)2]BF4 and [Co(bcn)2]BF4, respectively; and aceylpyrazine 3-aza-bicyclo[3.2.2]nonylthiosemicarbazone, [Co(Pzbcn)2]BF4, have been synthesized and their spectral properties measured. The1H and13C-n.m.r. spectra show the uncomplexed thiosemicarbazones to be mixtures of as many as three isomers, and that the two ligands in the cobalt(III) complexes are nearly identical. The crystal structure of [Co(Pzbcn)2]BF4 shows the two ligands coordinated in a mer-configuration. Bond lengths and angles in this complex are compared with data previously reported for thiosemicarbazone complexes. 相似文献
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Douglas X. West Brenda L. Mokijewski Haileselassie Gebremedhin Timothy J. Romack 《Transition Metal Chemistry》1992,17(5):384-386
1H and13C n.m.r. spectra are reported for a series of 2-acetylpyridine4
N-alkylthiosemicarbazones in order to study the effect of increased size of the alkyl function on the ratio of isomers present
in solution. Similarly, n.m.r. data for the bis(thiosemicarbazone)cobalt(III) complexes are included, as well as these complexes'
ligand field parameters.
TMC 2698 相似文献
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