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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Spectroscopic and collision dynamic studies of Na2̲ and I2̲

Astill, A. G. January 1987 (has links)
No description available.
2

De frontera fluvial imaginada a espectral río arborescente: nacimiento, cauces y contracorrientes de los imaginarios coloniales del río Magdalena en la literatura colombiana

Escobar Villegas, Julia 23 August 2022 (has links)
No description available.
3

Contribution to the knowledge of Chemical Northeast plants : Caesalpinia ferrea (Leguminosae) / ContribuiÃÃo ao conhecimento QuÃmico de plantas do Nordeste: Caesalpinia ferrea (Leguminosae)

Islay Lima MagalhÃes 19 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho descreve a investigaÃÃo fitoquÃmica da espÃcie vegetal Caesalpinia ferrea (Leguminosae), conhecida como âjucÃâ e usada popularmente no nordeste do Brasil como antirreumÃtico, antimicrobiano e entre outros usos. Os extratos de C. ferrea atravÃs da cromatografia em coluna tendo como fase estacionÃria gel de sÃlica e Sephadex LH-20 levaram ao isolamento de quatro substancias do tipo polifenÃis {Ãcido gÃlico (Ãcido-3,4,5-tri-hidrÃxi-benzÃico), Ãcido elÃgico (4,4â,5,5â,6,6â-hexahidroxidifÃnico-2,6,2â,6â-dilactona), amentoflavona (8-[5-(5,7-dihidroxi-4-oxo-cromeno-2-il)-2-hidroxi-fenil]-5,7-dihidroxi-2-(4-hidroxifenil) cromeno-4-one) e resveratrol (trans-3,5,4â-trihidroxiestilbeno)}; uma mistura constituÃda de um esterÃide {β-sitosterol (24-etilcolest-5-en-3β-ol) e de dois Ãcidos graxos [Ãcido palmÃtico (n-hexadecanÃico) e esteÃrico (n-octadecanÃico)]}; uma outra mistura constituÃda dos triterpenos [Lupeol (Lup-20(29)-en-3β-ol) e β-amirina (olean-12-en-3β-ol), do esterÃide 24-metilenocicloartanol (3β-9,19-Ciclolanostan-3-ol-24-metileno) e do Ãlcool lignocÃrico (n-tetracosonol). A caracterizaÃÃo dos compostos envolveu o uso das tÃcnicas de RMN 1H e 13C (1D e 2D), IV, CG-EM-IE e CLAE-EM-IES. Os extratos brutos das vagens e algumas de suas fraÃÃes foram submetidos a testes de atividades antiacetilcolinesterase e antioxidante com resultados promissores. O bi-flavonÃide, a fitoalexina e os constituintes das misturas mencionadas sÃo relatados pela primeira vez na literatura em C. ferrea. / This work describe the phytochemical investigation of pods and stems of specie Caesalpinia ferrea (Leguminosae) known as âjucÃâ. Popularly, this plant is used as antirheumatic, antimicrobial and among other uses. The hexane and ethanol extracts to pods and stems of C. ferrea were submitted to column chromatography having silica gel and Sephadex LH-20 as stationary phase that led to the isolation of four compounds of the type polyphenol: {gallic acid (3,4,5-trihydroxy-benzoic acid), ellagic acid (4,4', 5,5', 6,6'-hexahydroxydifÃnico-2,6,2',6'-dilactone), amentoflavone (8-[5-(5,7-dihydroxy-4-oxo-chromene-2-yl)-2-hydroxyphenyl]-5,7-dihydroxy-2-(4-hydroxyphenyl)) chromen-4-one and resveratrol (trans-3,5,4â trihydroxystilbene)}; a mixture consisting of a steroid {-sitosterol(24-etilcolest-5-en-3-ol) and two fatty acids [palmitic acid (nhexadecanoic) and stearic acid (n-octadecanoic acid)]}; another mixture consisting of the triterpenes [Lupeol (Lup-20(29)-en-3-ol) and -amyrin (olean-12-en-3-ol), steroid 24-metilenocicloartanol (3-9,19 Ciclolanostan-3-ol-24-methylene) and lignoceric alcohol (n-tetracosonol). The characterization of the chemical components involved the use 1H and 13C NMR (1D and 2D), IR, GC-MS-EI e HPLC-MS-ESI. The extracts of pods and some of its fractions were submitted in test of the antioxidant activities and antiacetylcholinesterase with promising results. The bi-flavonoid, phytoalexin and components of mixtures mentioned are first reported in the literature to C. ferrea.

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