Repositorio Académico de la Universidad de Chile: Recent submissions
Now showing items 43981-44000 of 98905
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(1990)2,4-Dihydroxy-7-methoxy- 1,4-benzoxazin-3-one (DIMBOA), the main hydroxamic acid of wheat, and its decomposition product 6-methoxy-benzoxazolin-2-one (MBOA), inhibited 50% root growth of wild oat, Avena fatua at concentrations ...
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(1999)C12H18I2O2, triclinic, P1̄ (No. 2), a = 10.297(3) Å, b = 11.775(3) Å, c = 12.337(4) Å, α = 93.8(2)°, β = 96.8(3)°, y = 104.6(2)°, V = 1430.1 Å3, Z = 4, Rgt(F) = 0.062, RW(F2) = 0.163, T= 298 K. © by R. Oldenbourg Verlag,.
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(1999)C16H24O5, monoclinic, P121/c1 (No. 14), a = 14.941(2) Å, b = 11.213(2) Å, c = 9.888(2) Å, β= 101.4(1)°, V= 1623.9 Å3, Z = 4, Rgt(F) = 0.051, RW(F2) = 0.113, T = 293 K. © by R. Oldenbourg Verlag,.
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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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(1995)In this paper I examine the extent to which contemporary ecological patterns in 42 harvester ant assemblages of three continents can be explained as a result of present-day environments or from differences in the history ...
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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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(Elsevier Ltd, 1998)We discuss the recent appearance of very broad (FWZI∼20000 km s-1) double-peaked Balmer emission lines in the nuclei of the galaxies NGC 1097, Pictor A and M 81. Such profiles are rare, and only found in about 10% of ...
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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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(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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(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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Effect of gramine on the feeding behavior of the aphids Schizaphis graminum and Rhopalosiphum padi (1988)The effects of the indole alkaloid gramine on the behavior of the aphids Schizaphis graminum and Rhopalosiphum padi feeding on barley seedlings and on artificial diets were studied. On barley cv. F. Union, which lacks ...
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(1995)This article analyzes the conflict between traditional beliefs, cultural roles, and the search for individuality through the study of Fresia, a young Mapuche woman who renounced shamanistic practice. Her case demonstrates ...
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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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(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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(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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(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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(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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(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 ...
