Artículos de revistas: Recent submissions
Now showing items 821-840 of 4968
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(1992)During some biogeochemical processes mediated by bacteria, essential nutrients such as phosphate can become limiting for the microorganisms, affecting their biological activity. We have analyzed changes in total protein ...
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(1988)p-Phenylene and p-biphenylene-bridged methylated cyclopentadienyl rings were prepared. Reaction of the dilithio salts of the ligands with (η5-C5Me5)Fe(acac) provides cleanly ferrocenes bridged by p-phenylene and p-biphenylene ...
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(1990)Three protease fractions were obtained by purification of a thistle extract with ammonium sulfate. The optimum pH and temperature on the proteolytic activity of the crude extract was found to be 5·7 and 37°C, respectively. ...
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(1984)We consider systems of differential equations of the form (1) x’ = f(t,x), for t ∊ [a,∞), x in some domain D ⊂ IRn and f ∈ c1 ([a,∞) × D) (a a fixed real number). We assume that the solution x(t,to,xo) of (1) defined for ...
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(1995)We consider a system of the form u’' + au’ = Hv(u, v)-h(t) v’' + bv’ = Hu(u, v)-k(t), where h, k are locally integrable and T-periodic, and H is a C1 function defined on (0,∞)x(0,∞), for which a good model is given by H(u, ...
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(1992)Relative reactivities of potassium persulfate (KPS) and ferrous ammonium sulfate-potassium persulfate (FAS-KPS) systems, in aqueous medium, as initiators for grafting of methyl methacrylate (MMA) onto chitin, were studied. ...
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(Elsevier, 2000)The infrared spectra of the azabipiridyl macrocycle complexes of Ni(II), Cu(II) and Zn(II) were registered between 4000 and 200 cm-1. The spectral assignment allowed to identify the complex formation and structural differences ...
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(1998)The infrared spectra of naphthalocyanine (H2Nc) and its copper(II) complex (CuNc) were registered in the region 4000-450 cm-1. These compounds were deposited onto a smooth copper surface and their specular infrared spectra ...
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(1980)Hydroxamic acid concentration in Gramineae, both natural and incorporated, correlates with resistance to the aphid Metopolophium dirhodum. 2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one, a hydroxamic acid isolated ...
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(1996)A theoretical evaluation of inelastic transition amplitudes corresponding to collisions between low-energy electrons (up to 5 eV) and small metallic clusters is presented. The target is excited into a particle-hole state ...
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(1997)We have used a deep CO survey of the third galactic quadrant (May et al. 1993) to derive the physical properties of molecular clouds in the outer Galaxy. Within the range of this survey, from 194° to 270° in galactic ...
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(Elsevier, 1999)The IR spectra of the M(mnt)(baba) where M = Ni and Pd, mnt = 1,2-maleonitrile and baba = biacetylbisanyline, were recorded in the high as well in the low energy region. A complete assignment of the observed bands was ...
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(Elsevier, 1999)The possibility of gaining insight into chemical bonding and reactivity through various local temperatures and associated entropy densities is explored. Comparisons of these quantities with other local reactivity descriptors ...
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(1990)The negative ions of the alkaline-earth-metal atoms (Be to Ba) have been studied by means of a pseudopotential model together with configuration- interaction and multiconfiguration self-consistent-field techniques. Only ...
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(1999)In this paper we consider a class of nonlinear singularly perturbed elliptic problems of the form ε2 Δu - u + f(u) = 0 in Ω, for a superlinear, subcritical function f. Here Ω a smooth bounded domain, ε > 0 is a small ...
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(1995)Deuterium quadrupole splittings from the aromatic ring of a series of deuterium labeled n-alkylpyridinium ions with linear n-alkyl groups from Ci to Cie have been measured using 2H-NMR spectroscopy. These splittings were ...
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(1988)From Schizanthus pinnatus Ruiz et Pav. we have isolated seven new tropan-3α,6β-diol diesters, schizanthines F (1), G (2), H (3), I (4), K. (8), L (9), and M (10), together with tropine, (-) -6β-angeloyloxytropan-3α-ol (5), ...
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(1985)The hydroxamic acid content of leaves of cereals correlates well with resistance to aphids. In maize these compounds were absent from xylem exudates and guttation drops. Lateral veins of leaves of 7-day-old maize plants ...
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(1985)The content of the simple indole alkaloid gramine in barley leaves decreased with age. Conversely, susceptibility to aphids increased in older plants. Population growth rate of the greenbug Schizaphis graminum correlated ...
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(Springer-Verlag, 1977)High-alumina basalts from seven High-Andean stratovolcanoes (37 °30′S to 41 °S) have major and trace element (including rare earth elements, REE) that are consistent with derivation by partial melting (typically 10-15%) ...
