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101.
Belen Lpez Juan Rocha Kishin Sadarangani 《Mathematical Methods in the Applied Sciences》2019,42(1):49-58
In this paper, Lyapunov‐type inequalities are derived for a class of fractional boundary value problems with integral boundary conditions. As an application, we obtain a lower bound for the eigenvalues of corresponding equations. 相似文献
102.
Zélia da Rocha 《Journal of Difference Equations and Applications》2019,25(1):97-118
Orthogonal polynomials satisfy a recurrence relation of order two defined by two sequences of coefficients. If we modify one of these recurrence coefficients at a certain order, we obtain the so-called perturbed orthogonal sequence. In this work, we analyse perturbed Chebyshev polynomials of second kind and we deal with the problem of finding the connection coefficients that allow us to write the perturbed sequence in terms of the original one and in terms of the canonical basis. From the connection coefficients obtained, we derive some results about zeros at the origin. The analysis is valid for arbitrary order of perturbation. 相似文献
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105.
Various quinol-4-yl hydrazones on heating in high boiling solvents undergo cyclizations to give lH-pyrrolo[3,2-c]quinolines in good yields. Some of these pyrroloquinolines were alkylated to provide their N-alkyl derivatives. 相似文献
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107.
A technique for the separation of human alloalbumin variants by means of isoelectric focusing in the presence of 8M urea and 60 mM L-serine is described. The potential usefulness of this technique in the detection and classification of genetic heterogeneity at the albumin locus is demonstrated by the differentiation of three human alloalbumin variants of European origin. 相似文献
108.
Díez D Sanchez JM Rodilla JM Rocha PM Mendes RS Paulino C Marcos IS Basabe P Urones JG 《Molecules (Basel, Switzerland)》2005,10(8):1005-1009
Incubation of sclareol with Rhizopus stolonifer affords in high yield a mixture of triols with 18-hydroxy-sclareol as the main component. 相似文献
109.
1-Phenyl-, and 1-nitrophenylindoles when subjected to Mannich reaction conditions gave the corresponding 3-dialkylaminomethyl derivatives ( IIc-IIk ) in good yields. 相似文献
110.
Freire RO da Costa NB Rocha GB Simas AM 《The journal of physical chemistry. A》2006,110(17):5897-5900
The sparkle/AM1 model for the quantum chemical prediction of coordination polyhedron crystallographic geometries from isolated lanthanide complex ion calculations, defined recently for Eu(III), Gd(III), and Tb(III) (Inorg. Chem. 2005, 44, 3299) is now extended to La(III) and Lu(III). Thus, for each of the metal ions we chose a training set of 15 complexes that possess various representative ligands of high crystallographic quality (R factor < 0.05 Angstroms) and oxygen and/or nitrogen as coordinating atoms. In the validation procedure we used a set of 60 more La(III) coordination compound structures, as well as 15 more Lu(III) coordination compound structures, all of high crystallographic quality. For both the 75 La(III) compounds and the 30 Lu(III) compounds, the Sparkle/AM1 unsigned mean error, for all interatomic distances between the metal ions and the ligand atoms of the first sphere of coordination, is 0.08 Angstroms, thus comparable to the accuracy normally achievable by present day ab initio/ECP calculations, while being hundreds of times faster. 相似文献