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Co-adsorbing effect of bile acids containing bulky amide groups at 3β-position on the photovoltaic performance in dye-sensitized solar cells
(2019)
Co-adsorbing molecules attain certain control in the surrounding of the dyes leading to enhanced efficiencies
mainly by affecting the recombination of the photogenerated electrons and aggregation of dyes. Bile acids ...
Reacción del Oxido de Etileno con Clorhidratos de Aminoácidos
(1978)
Se estudió la reacción del óxido de etileno con clorhidratos de aminoácidos a bajas temperaturas. Esta reacción conduce a la obtención de los aminoácidos libres. Se probó la eficiencia de este nuevo método de purificación ...
Germacranolides and other constituents from ageratzna species
(1988)
The aerial parts of Ageratina anisochroma gave several thymol derivatives including five new ones, a hydroxypiperitol glucoside, some substituted benzyl benzoates and several germacranolides related to provincialin. From ...
Índice fisicoquímico de la calidad de agua para el manejo de lagunas tropicales de inundación
Physicochemical water quality index, a management tool for tropical-flooding lagoons
(2008-12-01)
We
propose ICA-L, a wetland physicochemical water quality index (WWQI), to be used as a management tool for
seasonal-flooding lagoons in Palo Verde National Park, Guanacaste, Costa Rica. The goal is to preserve their ...
Photochemische Umlagerung von 1-Acyloxy-1-alkoxy-λ5-phosphorin-Derivaten
Photochemical rearrangements of 1-acyloxy-1-alkoxy-λ5-phosphorine derivatives
(1976)
Während bei 1-Akoxy-1-benzoyloxy-2,4,6-triphenyl-λ5-phosphorin-Derivaten 1a-e photochemisch in Ausbeuten von 46 - 96% dieselben 1-Alkoxy-6c-benzoyl-1r-oxo-2,4,6-triphenyl-1λ5-phospha-2,4-cyclohexadiene 2a-e isoliert werden, ...
Influence of nanosilica and diatomite on the physicochemical and mechanical properties of binder at unaged and oxidized conditions
(2016)
Modification of binders helps address common distresses in pavements by changing their essential properties. In order to further characterize the role of additives in these changes, a set of nanosilica and diatomite modified ...
Residuos de plaguicidas organoclorados en tejido adiposo humano en Costa Rica
(1986)
Organochlorine pesticide residues were found in 82 samples of human adipose material fram 82 surgical cases in 16 Costa Rica hospitals. Identification was made by gas-liquid chromatography. The highest pesticide concentration ...
Chemical Investigations of Tropical Medicinal Plants, XXI [1] Long Chain Alkyl Esters of Ferulic and p-Coumaric Acid from Bauhinia manca
(1986)
Bauhibia manca (Leguminosae) is a vine growing in the lowland forests of Costa Rica and Panama [2]. In Costa Rica, an infusion of the stems and leaves is taken as an astringent and diuretic, and as a remedy for diabetes[3,4] ...
An improved stereospecific synthesis of (Z,E)-9, 11, 13-Tetradecatrienal. Sex pheromone component of Stenoma cecropia
(2000)
(Z,E)-9,11,13-tetradecatrienal, a pheromone component of Stenoma cecropia, was prepared in 61% overall yield from 1-nonyne. The synthesis involved two palladium-catalyzed cros-couplings to afford a 1,3-dien5-yne, which was ...