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This article presents results on the use of a new material as a solidifying agent and/or color- fixing agent. A special polysaccharide material extracted from the prickly pear cactus (Opuntia ficus indica) was tested on historical materials and modern papers. An old book from the 18th century was chosen as historical material. From the mentioned book 42 pages were taken, on which a conservation and restoration pretreatment was performed before applying the polysaccharide material: sampling, fiber analysis, dry cleaning, ink solubility, pH test, thickness measurement and wet cleaning. The paper sheets provided for the test were divided into 4 groups, 3 of which were treated with gel and one left untreated as a reference. The division into groups is not only due to the different method of application, but also due to the process of gel extraction. The effect of the treatment was analyzed using FTIR- ATR. To test the mucilage as color-fixing agent 2 samples were prepared using watercolor papers colored with 6 different watercolors applied to 2.5 cm2 samples for each color in two rows of different intensity. One of the 2 samples was treated with gel, but both were immersed for 3 times in a water-ethanol solution for approximately 20 min as is standard practice in conservation and restoration. After washing, both specimens were subjected to colorimetric analysis to assess their differences. The results provided satisfactory evidence for the protection of paints sensitive to aqueous treatments and suggest the use of mucilage as a new material in cleaning method for water-soluble media.

Prvi dio radionice uključuje izradu papira tradicionalnim načinom proizvodnje od ostataka papirnih predmeta (pripremu sirovine, mljevenje, rastvaranje papirne pulpe u vodi, izvlačenje formiranoglista papira na sito te stabiliziranje strukture nosioca za potrebe pisanja ili slikanja). Drugi dio radionice je kreativnog karaktera pri čemu će sudionici imati priliku od prethodno dobivenih listova izraditi vlastite personalizirane knjižice/blokove koje će moći ponijeti sa sobom. Za izradu vlastitih kreativnih likovnih modela koji će stajati na prvoj stranici. Na zadnjoj stranici knjižice nalazit će se receptura po kojoj će svi moći jednostavno izraditi papir i sami kod kuće.

This paper will present the results concerning the use of new material as a consolidant and/or colour protector. A specifi c polysaccharide material extracted from the prickly pear (Opuntia fi cus indica) has been tested on modern papers and historical materials. An ancient book (18th-19th century) was chosen as historical material. Before applying the polysaccharide material, a conservationrestoration preliminary treatment was carried out on the book’s pages: sampling, fi bre analysis, dry cleaning, ink solubility, pH test, thickness measurement, and wet cleaning. The polysaccharide material was then applied with different techniques, and the treated sheets were analysed by FTIR- ATR. In the second part of our work, we decided to use the mucilage extracted from Opuntia Ficus Indica to test its use as a colour fi xative. Thus, the procedure involves removing impurities with wet cleaning, with the sample wholly immersed in water. This cleaning is the best method for removing contaminants from the paper or fabric backing, it can be used on paper or objects painted in watercolour. The material was applied in different ways (with extraction in alcohol and solid form by means of a spraydryer in various percentages with sericin), and a physico- chemical characterization was carried out by FTIR- ATR and SEM analyses. The results gave excellent evidence of the protection of colours sensitive to aqueous treatments. Therefore, applying this material can be suggested as a new cleaning method for water- soluble materials.

Photochemistry of Heterocycles is a comprehensive review of the topic, including photooxidation, photoreduction and photoaddition reactions as well as industrial aspects of heterocyclic photochemistry. Many materials used for the manufacturing of OLEDs and other electrooptical switches contain heterocycles, and the use of small molecules or polymers containing heterocyclic substances are being studied as new photovoltaic materials. This reference is ideal for synthetic organic chemists, specifically researchers working in organic photochemistry, as well as medicinal chemists and material scientists. Heterocyclic compounds are widely used in the modern world, and most of the drugs currently in use have heterocyclic nuclei among their constituents. These compounds are subject to a photochemical degradation processes which must be known and prevented.

The photochemical reaction between aromatic carbonyl compounds and 3-furylmethanol derivatives occurs with high regioselectivity. In most of the experiments formation of oxetanes occurs at the hydroxyalkylated double bond. With chiral 1-(3-furyl) alkanols the reaction occurs with good-high stereoselectivity. In the case of 1-(3-furyl)-benzyl alcohol the stereoselectivity can be explained on the basis of the conformers of the reagent, assuming the formation of a complex between the carbonyl compound and the hydroxyl group.

Photochemical and anionic polymerizations of 1, 2-diaza-1, 3-butadienes are described. Photochemical polymerization was smoothly performed by irradiation of some 1-amino-carbonyl-1, 2-diaza-1, 3-butadienes with high pressure mercury arc (lambda = 300 nm) in the presence of allyltributylstannane. Molecular weights (M-w) in the range 14.6-559 x 10(2) g/ mol were obtained. The TGA curve revealed a first weight loss starting at about 200 degrees C of some 85%, and a second starting at about 300 degrees C. The DSC showed the glass transition (T-g) at about -34 degrees C. Anionic polymerization was performed by treatment of some 1-alkoxycarbonyl-1, 2-diaza-1, 3-butadienes with n-butyllithium. Molecular weights (M-w) in the range 8.44-242 x 10(2) g/mol were obtained.

HS-SPME-GC-MS analysis of Fiano di Avellino (white wine, Southern Italy) and Aglianico del Vulture (red wine, Southern Italy) showed the presence of ethyl acetate, 2-methyl-1-propanol, 2-methyl-1-butanol, 2-methylbutyl acetate, ethyl hexanoate, diethyl butanedioate, ethyl octanoate, and ethyl decanoate. Uv irradiation of both the wines in a Pyrex vial with a 15 W low pressure mercury arc showed an extensive degradation of all the compounds. Only in the case of diethyl batanedioate, 2-methylbutyl acetate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate in the red wine the degradation occurred after an initial increase of the concentrations of the esters. The irradiation of the esters in the presence of riboflavin showed a clear degradation of the esters. The irradiation of both the wines in the original bottles for seven days showed an extensive degradation of all the volatile organic compounds observed in the wines.

L’ IPERFORINA HA IL LIMITE DI NON ESSERE STABILE ALLA LUCE. IN QUESTO LAVORO VIENE RIPORTATA LA CARATERIZZAZIONE DEI SUOI PRODOTTI DI FOTODEGRADAZIONE.L’ ANALISI HPLC INDICA CHE DOPO 5 ORE DI IRRAGGIAMENTO, CON UNA LAMPADA AD ARCO DI MERCURIO, L’ IPERFORINA RISULTA ESSERE COMPLETAMENTE DEGRADATA A DARE UN UNICO PRODOTTO CHE E' STATO CARATTERIZZATO.

4-Amino-2, 7-dimethylbenzo[b]furan and 4-chlorobenzo[b]furan have been synthesized. The irradiation of 4-amino-2, 7-dimethylbenzo[b]furan in the presence of benzaldehyde gave the corresponding endo adduct. The adduct can be hydrolysed to the corresponding 3-benzofurylmethanol derivative. The irradiation of the same compound in the presence of benzophenone gave the corresponding adduct. 4-Chlorobenzo[b]furan did not react with benzaldehyde while, in the presence of benzophenone, gave the corresponding adduct. The hydrolysis of this adduct gave the corresponding 3-benzofurylmethanol derivative.

E’ stato riportato che l’ irradiazione di 2-furilcarbinoli in presenza di composti carbonilici aromatici o alifatici porta alla formazione dei corrispondenti addotti ciclici con diversa regio- e stereoselettivit&agrave ; . Nei casi in cui si &egrave ; avuta alta stereoselettivit&agrave ; , questa &egrave ; stata spiegata ipotizzando la formazione di un legame idrogeno fra l’ ossigeno carbonilico e l’ idrogeno ossidrilico.1-4 Sulla base dei risultati ottenuti ci siamo proposti di studiare il comportamento fotochimico dei 3-furilcarbinoli allo scopo di verificare un comportamento analogo. La reazione con il benzofenone &egrave ; stata regiospecifica e completamente stereoselettiva: l’ unico regioisomero, ottenuto dall’ attacco sul lato pi&ugrave ; ingombrato dell’ anello furanico, &egrave ; risultato essere un singolo diastereoisomero, come si evince dall’ analisi HPLC. La configurazione &egrave ; stata attribuita tramita analisi NOE.

Si &egrave ; studiato l'effetto della luce UV sul vino bianco e rosso. si &egrave ; osservata una degradazione degli esteri nel vino bianco, cosi come nel vino nero dopo un iniziale incremento. Lo stesso effetto si &egrave ; verificato irradiando il vino direttamente nelle bottiglie.

IN QUESTO STUDIO VENGONO PRESENTATI I RISULTATI RELATIVI ALLA POLIMERIZZAZIONE FOTOCHIMICA DEI COMPOSTI 1, 2-DIAZA-1, 3-BUTADIENICI . LA REAZIONE E’ STATA REALIZZATA IRRADIANDO IL MOMOMERO E L’ INIZIATORE IN BENZENE, IN UN APPARATO AD IMMERSIONE CON UNA LAMPADA AD ARCO DI MERCURIO, A DIVERSE TEMPERATURE ED ADOPERANDO DIVERSI RAPPORTI MOLARI. TALI VARIAZIONI NON HANNO PERO’ INDICATO ALCUNA DIFFERENZA SIA NELLE RESE CHE NEI TEMPI DI REAZIONE, PER CUI SI SONO CONSIDERATE OTTIMALI LE CONDIZIONI PIU’ SEMPLICI: RAPPORTO EQUIMOLARE DEI DUE REATTIVI E TEMPERATURA AMBIENTE. SI E’ , INOLTRE, TESTATA LA REATTIVITA’ DI DIVERSI MONOMERI E INIZIATORI.IL PRODOTTO E’ STATO CARATTERIZZATO MEDIANTE NMR, GPC, TGA.

Si &egrave ; studiato il comportamento fotochimico e fotofisico dell'etil 2-iodotiazolo-5-carbossilato. Si &egrave ; inoltre tentato di ipotizzare un meccanismo per la rezione di trasposizione

IN QUESTO LAVORO VENGONO RIPORTATE LE REAZIONI FRA GLI ESTERI CHIRALI DELL’ ACIDO FENILGLIOSSILICO ED IL FURANO IN PRESENZA DI DIVERSE ZEOLITI DI TIPO Y O DI b-CICLODESTRINA.IN PRESENZA DELLE ZEOLITI, LA REAZIONE MOSTRA UN INCREMENTO DI STEREOSELETTIVITA’ CHE PUO’ ESSERE SPIEGATO CONSIDERANDO L’ INTERMEDIO BIRADICALICO COINVOLTO NELLA REAZIONE.NELLA CICLODESTRINA LA REAZIONE HA LUOGO CON UNA RESA E UNA DIASTEREOSELETTIVITA’ PIU’ BASSE. IN PARTICOLARE LA MANCATA STEREOSELETTIVITA’ PUO’ ESSERE SPIEGATA SE SI CONSIDERA LA PRESENZA DI BEN 21 GRUPPI OSSIDRILICI NEL MEZZO ORGANIZZATO. QUESTI INTERAGENDO CON IL GRUPPO CARBONILICO LO RENDONO INCAPACE DI DISTINGUERE LE DUE FACCE PROCHIRALI DEL FURANO.

The treatment of diluted olive oil mill waste water with Fenton's reagent reduces COD. The reaction followed a zero order kinetics' The reaction needs to use large amounts of reagents to have an appreciable reduction of COD. Treatment of olive oil mill waste water with ozone reduces COD. The reaction followed a first order kinetics. The UV spectrum of olive oil mill waste water after treatment with ozone did not show absorptions.

on areport&egrave ; les resultats de l'utilisation de l’ ozone dans la degradation de deux produits phytosanitaires

Il 4-Ammino-2, 7-dimetilbenzo[b]furano e il 4-clorobenzo[b]furano sono stati sintetizzati. l'irradiazione del 4-ammino-2, 7-dimetilbenzo[b]furano in presenza di benzaldeide ha fornito il corrispondente addotto endo. Questo puo essere idrolizzato al corrispondente 3-benzofurilmetanolo derivato. in presenza di benzofenone si forma il corrispondente addotto. Il 4-Clorobenzo[b]furano non reagisce con la benzaldeide mentre, in presenza del benzofenone, ha dato il corrispondente addotto che per successiva idrolisi ha fornito il corrispondente 3-benzofurilmetanolo derivato. Izvorni jezik: ENG

The photochemical reaction of 1-phenyl-2-methyl-1-butanone with furan gave propiophenone via a Norrish Type II reaction. The same behavior was observed using 1-phenyl-2-methyl-1-pentanone. In this case, the product derived from a Norrish-Yang reaction was obtained. The photochemical reaction of 2-phenylpropiophenone with furan and 2-methylfuran gave the corresponding Paterno-Buchi adducts. 2-Methylfuran gave a mixture of regioisomers. All the products of the Paterno-Buchi reaction were obtained with >98% de. The diastereoselectivity was explained by considering the relative stability of the biradical intermediates

Extending our investigations on environment protection by agrochemicals diffusion and accumulation, newly formed inclusion combinations of rimsulfuron into zeolite-NaY (Z-NaY) and beta-cyclodextrin (beta-CD) were studied and compared. The reactivity of the included herbicide under UV-irradiation and in the dark was assessed. Many guest/ host ratios were tested: the best results were found using 3 g (6.953 mmol) of rimsulfuron per kilogram of zeolite, with 80% inclusion success (5.562 mmol kg-(1)), and a 1: 2 molar ratio, 190 g of rimsulfuron per kilogram of beta-CD with 58% inclusion success. The herbicide Z-NaY-combined underwent rapid and effective (halflive 2-7 h) degradation either catalytically or photochemically, giving rise to different identified by-products. On the contrary, beta-CD was able to protect rimsulfuron totally both in the dark and under 24-h direct UV irradiation. On the basis of the obtained results, a different utilization of the two inclusion materials has been suggested.

A review primarily covering the Paternò ; ; -Buchi reaction.

La reazione di benzoino, 4, 4'-dimetossibenzoino e benzoino etil etere con furano ha dato il corrispondente addotto con elevata stereoselettivit&agrave ; (71-100%). questo risultato puo essere spiegata dalla diversa stabilit&agrave ; dei biradicali intermedi. Benzofurano reagisce con l'(S)-1-metilpropilbenzoilformate per dare il corrispondente addotto con de = 58%.

The photochemical coupling reaction between 2, 3-dihydrofuran and benzaldehyde was studied by using DFT/B3LYP/6-31G+ (d, p) method. The regiocontrol of the attack of the benzaldehyde on the double bond is related to the different stabilities of the biradical intermediates. The endo stereoselectivity of the reaction depends on the superposition between HSOMO and LSOMO in the biradical intermediate. In the photochemical reaction between furan and benzaldehyde also the regiocontrol depends on the relative stability of the possible biradical intermediates. The exo stereoselectivity of the coupling reaction depends on the superposition between the HSOMO and LSOMO of the biradical intermediate. The reaction of chiral phenylglyoxylates with furan gave the corresponding adducts with de = 15 - 95%. The stereocontrol can be explained considering the energy gap between the biradical intermediates in the coupling reaction. When the reaction was performed in the presence of zeolite, the diastereoisomeric excess increased. The reaction of benzoin and 2-phenylpropiophenone with furan gave the cycloadduct with high diastereocontrol. All the products were obtained with de > 98%. The Paterrno-Buchi reaction between 2-furylmethanols with aromatic carbonyl compounds also showed high regio- and stereocontrol. On the contrary, when 5-methyl derivatives were used, a lack of regiocontrol was observed. Furthermore, with aliphatic carbonyl compounds, no diastereoselectivity was observed. These results were explained assuming the attack of the excited carbonyl compound on the same side as the hydroxyl group, through the formation of a hydrogen bond or of a complex. This type of attack gave the biradical intermediate in preferential conformations. The relative energies of these conformers account for the observed diastereoselectivity.

la reazione di alcuni derivati del fuarno &egrave ; ; stata studiata dal punto di vista della regio e diastereochimica.Si &egrave ; ; , inoltre, testata la possibilita di indurre diastereoselettivita realizzando la reazione su zeoliti diverse.

The reaction of benzoin, 4, 4'-dimethoxybenzoin and benzoin ethyl ether with furan gave the corresponding adduct with high diastereoselectivity (71-100%). The diastereoselectivity was explained considering the relative stability of the biradical intermediates. Benzofuran reacts with (S)-1-methylpropylbenzoylformate to give the corresponding adduct with de = 58%. The diastereoselectivity was explained considering the relative stability of the biradical intermediates.

The photochemical reaction of 1-(2-furyl)-1-phenylethanol with benzaldehyde gave a mixture of regioisomeric products. The adduct obtained on the more hindered side of the molecule was obtained with complete diastereoselectivity. The same substrate with benzophenone gave only one product with a diastereoisomeric excess of 48%. The reaction of 2-(2-furyl)- 3, 3-dimethylbutan-2-ol with benzaldehyde and benzophenone gave the corresponding adducts on the more hindered side of the molecule with diastereoisomeric excesses of 42 and 71%, respectively. These results, and also those obtained using 2-furylphenylmethanol with benzophenone and acetone ( complete diastereoselectivity and absence of diastereoselectivity, respectively), were explained assuming the attack of the excited carbonyl compound on the same side as the hydroxy group, through the formation of a hydrogen bond or of a complex. This type of attack gave the biradical intermediate in preferential conformations. The relative energies of these conformers account for the observed diastereoselectivity.

The reaction of benzoin, 4, 4'-dimethoxybenzoin and benzoin ethyl ether with furan gave the corresponding adduct with high diastereoselectivity (71-100%). The diastereoselectivity was explained considering the relative stability of the biradical intermediates. Benzofuran reacts with (S)-1-methylpropylbenzoylformate to give the corresponding adduct with de = 58%. The diastereoselectivity was explained considering the relative stability of the biradical intermediates.

La regiochimica dell'attacco di un gruppo carbonilico su furano, 2, 3-diidrofurano, 2-metilfuranoe e 2-furilmetanolo fu spiegata assumendo un controllo degli orbitali molecolari di frontiera.La formazione preferenziale dell'addotto endo nella reazione fra 2, 3-diidrofurano e benzaldeide e quella dell'isomero eso nella reazione fra furano e benzaldeide fu spiegata considerando le relative stabilit&agrave ; degli addotti. Nel caso del 2-metilfurano, la reazione con la benzaldeide ha dato il prodotto derivante dal'attacco sul lato meno ingomgrato della molecola. La regiochimica fu spiegata considerando la relativa stabilit&agrave ; dei possibili intermedi biradicalici.

The reaction of (S)-1-methylpropylbenzoylformate with furan gave (1'S)-1'-methylpropyl (1S, 5R, 6R)-6alpha-phenyl-2, 7-dioxabicyclo[ 3.2.0] hept-3-en-6beta-carboxylate with de = 15%. The reaction of (S)-2-methylbutyl benzoylformate with furan gave (2'S)-2-methylbutyl (1SR, 5RS, 6RS)-6alpha-phenyl-2, 7-dioxabicyclo[3.2.0] hept-3-en-6beta-carboxylate as a mixture of stereoisomers. (1R, 2S, 5R)-5-Methyl-2-(1-methylphenylethyl) cyclohexyl benzoylformate gave (1R, 2S, 5R)5- methyl-2-(1-methylphenylethyl) cyclohexyl (1R, 5S, 6S)-6alpha-phenyl-2, 7-dioxabicyclo[3.2.0] hept-3-en-6beta-carboxylate with de = 95%. The stereochemical behaviour can be explained considering the energy gap between the biradical intermediates in the coupling reaction. When the reaction was performed in the presence of zeolite, the diastereoisomeric excess increased (37, 18 and 98%, respectively). The reaction of (S)-1-methylpropylbenzoylformate with 2-methylfuran gave (1'S)-1'-methylpropyl (1S, 5R, 6R)-1-methyl-6alpha-phenyl-2, 7-dioxabicyclo[3.2.0] hept-3-en-6beta-carboxylate (yield: 12%) with de = 94%. The main product was (1'S)-1'-methylpropyl (1SR, 5RS, 6RS)-3-methyl-6alpha-phenyl- 2, 7-dioxabicyclo[3.2.0] hept-3-en-6beta-carboxylate as a mixture of diastereoisomers. The reaction of (S)-2-methylbutyl benzoylformate with 2-methylfuran gave (2'S)-2-methylbutyl (1S, 5R, 6R)-1-methyl-6alpha-phenyl-2, 7-dioxabicyclo[ 3.2.0] hept-3-en-6beta-carboxylate (yield: 9%) with de = 10%. The main product was (2'S)-2-methylbutyl (1SR, 5RS, 6RS)-3-methyl-6alpha-phenyl-2, 7-dioxabicyclo[3.2.0] hept-3-en-6beta-carboxylate as a mixture of stereoisomers. The stereochemical behaviour can be explained on the basis of the energy gap between the possible biradical intermediates. The reaction of (S)-1-methylpropylbenzoylformate and (S)-2-methylbutyl benzoylformate with 2-furylmethanol gave the corresponding adducts as a mixture of diastereoisomers. The reaction of (S)-1-methylpropylbenzoylformate and (S)-2-methylbutyl benzoylformate with 2-furylphenylmethanol gave the corresponding adducts with high diastereoselectivity. In this case, the stereochemical behaviour is determined by the presence of the hydroxy group in a molecule with a preferntial conformation.

Lo champagne &egrave ; stato analizzato tramite analisi SPME prima e dopo irradiazione. La concentrazioni degli alcoli rilevati non sembra aver subito alcuna variazione, mentre si osserva una degradazione degli esteri.

usando il metodo DFT/B3LYP/6-31G+ (d, p), si sono studiate le reazioni di diversi derivati del furano. Il controllo regiochimico e stereochimico &egrave ; relazionato alla diversa stabilita dei biradicali intermedi.