Extração/pré-concentração de íons cobre no ponto nuvem explorando a formação de complexos com DMIT [4,5-dimercapto-1,3-ditiol-2-tionato]

The present study proposes a method for cloud point preconcentration of copper ions at pH 2.0 based on complexes formed with [4,5-dimercapto-1,3-dithyol-2-thionate] and subsequent determination by flame atomic absorption spectrometry (FAAS). Under optimal analytical conditions, the method provided limits of detection of 0.84 and 0.45 µg L-1, by preconcentrating 12.0 and 24.0 mL of sample, respectively. The method was applied for copper determination in water samples, synthetic saliva, guarana powder, tea samples and soft drinks and the accuracy was assessed by analyzing the certified reference materials Dogfish Liver (DOLT-4) and Lobster Hepatopancreas (TORT-2).

MÉTODO ALTERNATIVO PARA A SÍNTESE E MECANISMO DE 2-(1,3-DITIANO-2-ILIDENO)-ACETONITRILA

We report an alternative method for the synthesis of 2-(1,3-dithian-2-ylidene)-acetonitrile using 3-(4-chlorophenyl)-3-oxopropanenitrile and carbon disulfide as starting materials. The methanolysis of the intermediate 3-(4-chlorophenyl)-2-(1,3-dithian-2-ylidene)-3-oxopropanenitrile occurs via three possible intermediates, leading to the formation of the product at a 75% overall yield. Molecular modeling simulation of the reaction pathway using B3LYP 6-311G++(2df,2p) justified the proposed reaction mechanism.

1.° Regula sancti Benedicti : praemittuntur capitum index et prologus ; ad calcem vero haec leguntur : Anno ab Incarnatione Verbi 1129. quarto idus Decembris facta est abbatia Ursi-campi. — 2.° Traduction Françoise de la mesme régle. — 3.° Nomina ecclesiarum, sive monasteriorum sancti Benedicti quibus societas est cum monasterio Ursi-campi. — 4.° Sancti Benedicti vita : authore sancto Gregorio, Papa ; dimidia ferme pars desideratur

D. de Cangé

1.° Flores chronicorum fusiores, sive catalogus summorum Pontificum à S. Petro ad Joannem XXII. et Romanorum Imperatorum à Julio Caesare ad Henricum de Luxemburgo : authore Bernardo Guidonis ; subjiciuntur ejusdem flores chronicorum breviores. — 2.° Genealogia Regum Francorum à Trojana gentis origine ad Philippum Valesium : eodem authore. — 3.° Chronicon Regum Francorum à Pharamundo ad Philippum Valesium : eodem authore ; sequitur hujus chronici epitome. — 4.° Chronicon Comitum Tolosanorum : eodem authore. — 5.° Ejusdem tractatus brevis de temporibus et annis generalium et particularium Conciliorum : eodem authore.

nuper comparatus

1.° Adonis martyrologium, ad usum ecclesiae sancti Marii Badonensis : praemittitur libellus de festivitatibus Apostolorum et caeterorum qui Discipuli, aut vicini, successoresque ipsorum Apostolorum fuerunt. — 2.° Sancti Cypriani epistolae duae, prima ad Successum, altera ad Clerum et plebem. — 3.° Acta sancti Ignatii, Martyris. — 4.° Anonymi tractatus de gradibus perfectionis. — 5.° Passio S. Dei-votae, Virginis.

Mazarinaeus

1.° Legendae Sanctorum : authore Jacobo de Voragine, Januensi, ordinis Praedicatorum. — 2.° Vita sancti Willelmi, Abbatis primi Fiscannensis. — 3.° Adsonis, Monachi, ad Gerbergam, Franciae Reginam, epistola de ortu et tempore Antichristi. — 4.° Syntagma de Sibylla, sive vaticinatio de mundi fine.

Bigotianus

1.° Arnaldi de Villanova tractatus de aquis, de aëre, de vinis, de pane et leguminibus, et c. — 2.° Anonymi tractatus de signis frigiditatis matricis. — 3.° Tractatus de urinis, secundùm Arnaldum de Villanova. — 4.° Anonymi collatio artis chirurgicae. — 5.° Anonymi tractatus de apostematibus et pustulis : finis desideratur.

Colbertinus

1.° Joannis de Ravenna dragmalogia, sive dramatologia ; id est, dialogus Venetum inter et Paduanum de eligibili vitae genere. — 2.° Ejusdem conventio podagram inter et araneam. — 3.° Liber rerum memorandarum : authore eodem. — 4.° Historia Ragusii : eodem authore. — 5.° Historia familiae Carrariensis : eodem authore.

Tellerianus

1.° Anonymi varii tractatus de motu. — 2.° Bradwardini proportiones velocitatum in motibus. — 3.° Anonymi tractatus de elementis et eorum mixtione. — 4.° Anonymi tractatus de divisibilitate continui. — 5.° Nicolai de Ultricuria quaestio : utrùm visio creaturae rationalis beatificalis, per verbum possit intendi naturaliter.

Colbertinus

1.° Anonymi in Hippocratis librum de natura hominis commentarius. — 2.° Trium Galeni librorum de temperamentis epitome. — 3.° Compendium de epidemia, per collegium Facultatis Medicorum Parisiis ordinatum anno 1348. et è duobus manuscriptis exscriptum, altero Sanvictoriensi, altero Renati Morelli, Medici. — 4.° Tractatus de epidemia, à quodam practico de Montepessulano conscriptus anno 1349.

Mentellianus