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Studies of methamidophos-C-14 in Costa Rican vegetables and soils
(1984)
In order to see the effect of time lapse between the last application of methamidophos and harvesting insecticide was applied on lettuce plants (6,84 μCi in one experiment and 4,03 μCi in the other experiment). Analysis ...
Aggregation Pheromone of Coconut Rhinoceros Beetle, Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae)
(1995-10)
Male coconut rhinoceros beetles,Oryctes rhinoceros (L.), produce three sex-specific compounds, ethyl 4-methyloctanoate, ethyl 4-methylheptanoate, and 4-methyloctanoic acid, the first of which is an aggregation pheromone. ...
Drying kinetics as Tool for the Assessment of Dynamic Porosity of Catalyst-Support Materials
(2018)
Critical drying fraction data (xc) were obtained for a series of porous materials, frequently used
as supports for heterogeneous catalysts. This kinetic parameter correlates well with the secondorder rate constants for ...
Potent nor-triterpenoid blockers of the voltage-gated potassium channel Kv1.3 from Spachea correae
(1998)
The isolation and structure elucidation of two novel nor-triterpenoid KV1.3 potassium channel blockers correolide and dehydrocorreolide from the Costa Rican tree Spachea correae are reported.
The first potent and selective ...
La estructura de la Diacetonafenantrenoquinona
(1971)
The substance, diacetonephenanthrenequinone, long believed to have structure I or II, is found to have structure IV according to modern spectroscopic methods and chemical behavior.
Bis(μ2-benzoato-κ2O,O′)bis(benzoato-κO)bis(ethanol-κO)bis(μ3-hydroxido)hexakis(μ-pyrazolato-κ2N,N′)hexacopper(II) ethanol disolvate
(2019)
Trinuclear copper–pyrazolate entities are present in various Cu-based enzymes and nanojar supramolecular arrangements. The reaction of copper(II) chloride with pyrazole (pzH) and sodium benzoate (benzNa) assisted by ...
Metales traza (As, Cd, Co, Cr, Ni, Pb) en plantaciones bananeras de Costa Rica y efecto del cromo en el crecimiento y la absorción de nutrimentos en plantas de banano (Musa AAA)
(2021)
Los metales traza son elementos que se encuentran en bajas concentraciones en el
ambiente, generalmente menores a mil partes por millón. Algunos de estos elementos son
requeridos en el ciclo de vida ...
Nueva síntesis de la feromona sexual de la polilla del repollo Plutella Xylostella
(2007)
El compuesto (Z)-11-hexadecenal, feromona sexual de la polilla Plutella xylostella, fue preparado mediante tres secuencias sintéticas. La primer secuencia consistió de siete pasos y un rendimiento total de 47%. En las otras ...
Synthesis and antibacterial activity of Jacaranone and ester side chain analogs
(1991)
Jacaranone and several novel ester side chain derivatives have been synthesized and tested for antibacterial activity. The syntheses of these compounds involved the convenient lithium enolate ester adition to p-benzoquinone. ...
Fotorreducción de dióxido de carbono usando TiO2 sensibilizado con trímeros de Co y Cu en medio acuoso
Carbon dioxide photoreduction using TiO2 sensitized with Co and Cu trimers in aqueous media
Fotorredução de dióxido de carbono usando TiO2 sensibilizado com trímeros de Co e Cu em meio aquoso
(2021-01-31)
En la presente investigación, se evaluó el desempeño de dos fotocatalizadores de dióxido de titanio, uno sensibilizado con un trímero de cobre (Cu3(dpa)4Cl2) (dpa = 2,2 ́-dipiridilamina) y el otro con un trímero de cobalto ...