Listar Química por título
Mostrando ítems 120-139 de 360
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Electrochemical biosensor for quantitative determination of fentanyl based on immobilized cytochrome c on multi-walled carbon nanotubes modified screen-printed carbon electrodes
(2022)Fentanyl is a powerful synthetic opioid used to treat severe pain. New administration routes toward its illegal consumption for recreational purposes pose a growing threat to public health, either due to misuse or abuse ... -
Electrochemical determination of novel psychoactive substances by differential pulse voltammetry using a microcell for boron-doped diamond electrode and screen-printed electrodes based on carbon and platinum
(2021)25B-NBOMe, benzylpiperazine (BZP), 1-(3-chlorophenyl)piperazine (mCPP), and N,N-dimethyltryptamine (DMT) are potent hallucinogenic and stimulant drugs which have emerged as novel psychoactive substances (NPS). The ... -
Empleo de técnicas y materiales biológicos en la búsqueda de productos activos contra la malaria
(2001)Se describen los métodos empleados en el estudio del efecto de extractos de insectos preparados en el Instituto Nacional de Biodiversidad de Costa Rica, sobre un tipo de malaria murina producida por el Plasmodium bergheim. ... -
Ent-clerodane derivatives and other constituents from representatives of the subgenus ageratina
(1989)Ageratina ixiocladon afforded several p-hydroxyacetophenone derivatives and diterpenes including six new ent-clerodanes. Two further species, which are also placed in the subgenus Ageratina, gave p-hydroxyacetophenone ... -
Ent-clerodane derivatives from chromolaena connivens
(1989)The aerial parts of Chromolaena connivens afforded in addition to widespread compounds four ent-clerodane derivatives and two epimeric prostaglandin-like acids. A second species, C. turnariensis, only gave widespread ... -
Environmental Chemistry Group and Environmental Mineralogy Group Hold First Joint Meeting
(2018-08-01)Este blog describe las actividades académicas de los integrantes del Geomicro Group de la University of Manchester, Reino Unido, liderado por el Prof. Jonathan Lloyd. Esta publicación en particular, fue escrita por Agustín ... -
Espectro de Masas de Algunos Derivados del 9,10-Dihidrofenantreno
(1978)Discussion of the mechanisms of mass spectra fragmentation of some derivatives of 9,10-dihidrofenantreno -
Essential oil from leaves of Myrcianthes fragrans (Myrtaceae) from Costa Rica. A new chemotype?
(2017)Myrcianthes is a Myrtaceous genus of flowering plants of about 30 to 40 species, distributed in the American continent. The aim of this work was to study the chemical composition of the foliar essential oil from M. fragrans ... -
Essential oils of Baccharis trinervis (Asteraceae) from Costa Rica
(2017)Baccharis is an Asteraceae genus of flowering plants, which has about 340 to 400 species, ranging from the Southern United States to the Southern extreme of Argentina and Chile through Central America and the Caribbean ... -
Esteres mixtos derivados del trans-9,10-dihidroxi-9,10-dihidrofenantreno
(1982)Synthesis, structure elucidation, steric effects, and spectrometric analysis of some mixed esters of trans-9,10-dihydroxy-9,10-dihydrophenanthrene are discussed. The quasi-axial conformation of the two ester groups, in ... -
Estrogenic and serotonergic butenolides from the leaves of Piper hispidum Swingle (Piperaceae)
(Journal of Ethnopharmacology 129(2): 220–226, 2010)Ethnopharmacological relevance: Our previous work has demonstrated that several plants in the Piperaceae family are commonly used by the Q’eqchi Maya of Livingston, Guatemala to treat amenorrhea, dysmenorrhea, and pain. ... -
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. -
Estructura y Configuración de la Diacetona-Fenantrenoquinona
(1981)Estudio de la estructura y configuración molecular de la diacetona-fenantrenoquinona por difracción de rayos X y espectrometría de masas -
Estudio de aditivos anticorrosivos para las aleaciones comerciales de la batería alcalina alumino-aire
(2020)La sociedad actual está avanzando hacia un modelo energético más responsable y sostenible. La punta de lanza de esta necesaria tendencia es el uso de fuentes de energía renovables y la reducción de las emisiones de CO2 ... -
Estudio de Coherencia y Transporte Cuánticos en las Dinámicas Energéticas duranta la Captación de Energía Lumínica en Sistemas Fotosintéticos
(2022-11)The photosynthesis is one of the most studied biological processes through history. Its capacity to fix carbon into nutritional molecules is the base of all food chains. Its efficient exploitation of the solar energy ... -
Estudio de la biocompatibilidad de hidroxiapatita y su posible aplicación como vehículo para sustancias bioactivas
(2014-12)Las nanopartículas sintéticas se utilizan en aplicaciones médicas para el diagnóstico, la prevención y el tratamiento de las enfermedades. Algunos de los usos más destacados de estos biomateriales, a través de la ... -
Estudio de la seguridad química en bodegas de reactivos de laboratorios de investigación de la Universidad de Costa Rica: elaboración de una herramienta tecnológica para la identificación y manejo del riesgo químico
(2021)En este trabajo, se ha utilizado una matriz para determinar el riesgo químico, en la que se han unido la identificación y caracterización del peligro usando la determinación toxicológica de las sustancias de la OECD, ...