Results 11 to 20 of about 3,226 (122)
Studies of some effects on the preparation of spherical silica particles from reverse microemulsion
Eclética Química, 2018 Silica spherical particles were prepared in reverse microemulsion from sodium silicate solution precursor. Particle shape and size changes were investigated in function of reactants addition order, sodium silicate solution concentration and water to ...
Juliana Flor +2 more
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MAGNETIC NANOPARTICLES: THE COBALT
Eclética Química, 2018 The development of nanoparticles has been intensively pursued because of their technological importance. The magnetic nanoparticulate materials exhibit a series of interesting properties between which are mentioned the electrical, optical, magnetic and ...
Vagner Sargentelli, Antonio P. Ferreira
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HPLC Quantification of Cytotoxic Compounds from Aspergillus niger
Journal of Chemistry, 2017 A high-performance liquid chromatography method was developed and validated for the quantification of the cytotoxic compounds produced by a marine strain of Aspergillus niger.
Paula Karina S. Uchoa +5 more
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Angewandte Chemie, EarlyView.π‐Extended COUPY dyes, obtained by vinylogation of coumarin‐based COUPY scaffolds, shift absorption, and emission deep into the NIR region while preserving compactness and synthetic accessibility. These bright, photostable dyes enable live‐cell imaging, FLIM, and site‐specific peptide conjugation, offering a modular platform for targeted bioimaging and
Diego Abad‐Montero +11 more
wiley +2 more sources
Estudio longitudinal sobre la construcción de conceptos Enlace, solubilidad y conductividad
Educación Química, 2018 La finalidad central de este estudio se orienta hacia la búsqueda de las concepciones previas de los estudiantes de licenciatura en Química de la Facultad de Química de la UNAM, acerca de conceptos cuya adquisición resulta indispensable para comprender ...
Ana E. Domínguez +3 more
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Larvicidal Activity against Aedes Aegypti L. (Diptera: Culicidae) of Essential Oils of from Brazil
Natural Product Communications, 2006 The larvicidal activity of the essential oils from leaves of five species of Lippia (L. alba, L. aff. gracilis, L. gracilis, L. microphylla and L. nodiflora) was studied on third instar larvae of Aedes aegypti.
Gilvandete M. P. Santiago +11 more
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New Vibrational Information on Simple Amides in Solution: A Case Study on GaCl3-Formamide Complexes
Journal of Spectroscopy, 2020 IR and Raman measurements were carried out for GaCl3-formamide (FA) solutions, and comparisons with the Al3+ and Fe3+ chemistry are presented. Upshifts of both νCO and νCN modes of FA are observed, and analyses of the corresponding bands suggest ...
Anna K. M. S. Gomes, Wagner A. Alves
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Novel Lapachol Derivatives and Their Antioxidant Activity
Natural Product Communications, 2006 A convenient synthesis of the new enamine derivatives 2-diethylamino-3-(3-methyl-2-butenyl)-1,4-naphthalenedione ( 2 ), 2-ethylamino-3-(3-methyl-2-butenyl)-1,4-naphthalenedione ( 3 ), 2-diethanolamino-3-(3-methyl-2-butenyl)-1,4-naphthalenedione ( 4 ...
João P. S. Wenceslau +6 more
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Chemical Constituents and Insecticidal Activity of (Annonaceae)
Natural Product Communications, 2008 The present work describes the isolation of dehydrodiscretamine, discretamine, liriodenine, lichexanthone, molvizarin, rolliniastatin-1, annonacin and bullatacin from roots of Rollinia leptopetala R E Fries. The structures were established after analysis
Ângela M.C. Arriaga +9 more
doaj +1 more source
Antibacterial and Antioxidant Activities of Ursolic Acid and Derivatives
Molecules, 2014 Ursolic acid, an important bioactive compound, was isolated from ethanol extract of aerial parts of Sambucus australis. In order to develop bioactive ursolic acid derivatives, two semi-synthetic compounds were obtained through modification at C-3.
Patrícia G.G. do Nascimento +7 more
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