Repositorio Académico de la Universidad de Chile: Recent submissions
Now showing items 44081-44100 of 98852
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Determination of trace amounts of cobalt by solvent extraction-second derivative spectrophotometry (1993)A sensitive derivative spectrophotometric method is described for the determination of microamounts of cobalt based on the integration of liquid-liquid separation and reaction, in dichloroethane, of the analyte with ...
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(1983)The isolation of chilenone A from Laurencia chilensis and the determination of its structure by spectral and x-ray crystallographic techniques is described. © 1983.
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(John Wiley and Sons Ltd, 1998)Ground-state dipolar moments of oligomeric compounds, containing electron-donor (D) and electron-acceptor (A) groups as two terminal units of the polyenic bridge (D-wire-A), can well be described by means of a one-dimensional ...
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(Birkhäuser-Verlag, 1979)
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(1985)The decomposition of the title compound (DIMBOA, 1) in aprotic solvents was analysed in terms of linear solvation energy relationships using donor numbers. The results indicate rate-limiting cyclic hemiacetal opening in ...
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(Universidad Catolica del Norte, 2007)In this work we present a way to find asymptotic formulas for some solutions of second order linear differential equations with a retarded functional perturbation.
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(2003)C17H13NO2, monoclinic. P1211 (No. 4), a = 5.0336(5) Å, b = 13.964(2) Å, c = 9.025(2)Å,β = 98.56(1)°, V= 627.3 Å3, Z= 2, Rgt(F) = 0.069, wRref(F2) = 0.202, T= 293 K. © 2014, Oldenbourg Wissenschaftsverlag GmbH, Rosenheimer ...
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(Birkhauser Verlag Basel, 1998)We characterized the induction of hydroxamic acids (Hx) by aphid infestation in the wild wheat Triticum uniaristatum by addressing the following questions: i) Do different leaves have similar responses to aphid damage?, ...
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(Sociedad Chilena de Quimica, 2000)Reaction of CpFe(dppe)I with dithiopyridine in methanol and in presence of NH4PF6 affords the new mixed valence complex {[CpFe(dppe)]2 - n - S - Py}(PF6)2 (1 ). Observation of an intervalence electron transfer affords the ...
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(1998)The rates electron transfer ket for the mixed-valence complexes [Cd(dppe)Fe-CN-MLn]+2, MLn = Cp(dppe)Fe, Mn(CO)2dppmP(OPh)3 and other cyanide bridged complexes were estimated from the intervalence transition parameters. ...
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(Kluwer Academic Publishers, 1990)
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(1993)Four amphetamine derivatives bearing a methylenedioxy group at positions 3 and 4 of the benzene ring and differing in their substitution at C(6) were studied by differential pulse voltammetry in aqueous media. These ...
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(2003)C32H28N2O3, tridinic, P1 (No. 2), a = 8.648(8) Å, b = 10.27(1)Å, c = 15.31 (2) Å, α = 80.69(3)°, β = 73.71 (2)°, v = 84.13(2)°, V = 1286.1 Å3, Z = 2, Rgt(F) = 0.119, wRref(F2) = 0.379, T= 293 K. © 2014, Oldenbourg ...
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(Birkhauser Verlag Basel, 1999)The among-leaves allocation of DIBOA, a hydroxamic acid associated with plant resistance, in the shoot of rye (Secale cereale) was evaluated over the vegetative development of the plant. The appropriateness of using the ...
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(1992)We present a variational approach to the Heisenberg antiferromagnetic model for spin 1/2 and anisotropic exchange, with an external longitudinal and transverse magnetic field. In the one-dimensional case, we calculate ...
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(1998)In this work we developed a method by flow injection analysis for the determination of ranitidine in pharmaceutical forms and urine, using a polarographic flow through cell as detection system which has been designed ...
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(1993)In the present study a copper mixed valence (MV) compound has been generated photochemically from the (CH3COO)2Cu(II)Cu(II)(OOCCH3)2 dimeric species in 95/5% (vol./vol.) methanol/acetic acid mixture as solvent. The MV ...
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(1981)Results are presented for the total and metallic nickel areas of a series of coprecipitated nickel-alumina catalysts prepared and pretreated in different ways. The total areas of the samples decrease on reduction and with ...
