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Condensación de Cetonas Alifáticas con la Fenantrenoquinona en Hidróxido de Amonio
(1971)
A study on the synthesis and structure of the products of condensation of phenanthrenequinone with acetone and methyl-ethyl-ketone in presence of ammonia was
made. The structures were established by spectroscopic methods. ...
Residuos, Degradación y Persistencia del Fungicida Maneb en Patatas en Costa Rica
(1983)
Residues of the fungicide maneb (manganese-1,2-ethylen-bisdithiocarbamate) were analyzed by the carbondisulfide evolution method in samples of potatoes, potato leaves and soil from a commercial crop located in Llano Grande ...
Organic Carbon Determination by the Walkley-Black and Dry Combustion Methods in SurfaceSoils and Andept Profiles from Costa Rica
(1979-01)
The efficiency of oxidation of organic C by the Walkley-Black method was studied by comparing with determinations using dry combustion equipment and gravimetric determination for the evolved CO2. Fifty surface soils (0-30 ...
Fate of buturon-14C in soil during seven seasons of exposure under outdoor conditions
(1984-03)
Buturon (ring 14C) was applied to wheat and soil in two successive years (3 kg/ha each year) at outdoor conditions. Residual radioactive substances in the upper soil layer (0-10-cm depth) were measured 1.5, 2.5, 3.5, 6.0, ...
Fundamentos de Química Orgánica
(1985)
Este libro es una introducción a la Química Orgánica, para estudiantes de carreras médicas, Microbiología, Biología, Agricultura, Veterinaria. Llena un vacío entre textos escolares y libros de texto de la carrera de Química.
Derivados del fenantreno [9,10-d] Imidazol
(1981)
A simplified synthetic method of the phenanthro[9,10-d]imidazol (1) is reported in this work. The acetyl derivative (2) and a new cupric complex (3) of the imidazole (1) are synthesized, and the structures assigned on the ...
Reacciones del 2,2´-Tio-benzimidazol con Sulfato de Dimetilo
(1979)
Se efectuó la reacción del 2,2´-tiobis-benzimidazol con el sulfato de dimetilo por pasos. Se comprobó la formación de: 1,1´-dimetil-2,2´-tiobis-benzimidazol (2) y del diperclorato del 1,1´,3,3´-tetrametil-2,2´-tiobisbenz ...
Quimica Orgánica Experimental
(1978)
Los autores han tratado de reunir en este libro un conjunto de experimentos que permiten al profesor ejemplarizar todas las técnicas fundamentales del laboratorio de Química Orgánica y también ejemplarizar los compuestos ...
Paraquat Behavior in Costa Rican Soils and Residues in Coffee
(1990)
The paraquat deactivation capacities of soils, from 20 coffee plantations, generally ranged from 100 to 500 mg of paraquat/kg of soil. Even when paraquat had been applied up to twice per year (1.2 kg ha-1 year) for 20 ...
Kinetik und Thermodynamik einer thermischen Umlagerung in der λ5-Phosphorinreihe. Die Umlagerung von 1-Acetoxy-λ5-phosphorin* in 6-Acetyl-1-oxo-1λ5-phospha-2,,4-cyclohexadien
Kinetic and Thermodynamic of a Thermal Rearrangement in the λ5-Phosphorin Series The Rearrangement of 1-Acetoxy-λ5-phosphorin into 6-Acetyl-1-oxo-1λ5-phospha-2,4-cyclohexadiene
(1974-03)
Beim Erhitzen von 1-Acetoxy-1-isopropoxy-2,4,6-triphenyl-λ5-phosphorin (1c) in 1,4-Dioxan entsteht 6c-Acetyl-1-isopropoxy-1r-oxo-2,4,6-triphenyl-1λ5-phospha-2,4-cyclohexadien (2c), das durch säurekatalysierte Epimerisierung ...