PIERO BAGLIONI | Università degli Studi di Firenze (University of Florence) (original) (raw)
Papers by PIERO BAGLIONI
The Journal of …, Jan 1, 2007
A new double chained surfactant, 2-octyl-dodecanoyl-6-O-ascorbic acid (8ASC10), with a L-ascorbic... more A new double chained surfactant, 2-octyl-dodecanoyl-6-O-ascorbic acid (8ASC10), with a L-ascorbic acid unit as the polar headgroup was synthesized for the first time. The behavior of the compound in the dry solid state has been characterized through DSC, XRD, and SAXS measurements. The surfactant forms stable viscous organogels in the presence of suitable organic solvents and also water-induced organogels upon addition of water to the organogel. These mixtures show shear-thinning properties and are birefringent. The behavior and properties of the organogels have been studied through rheology, DSC, and SAXS experiments. The organogels possess the same antioxidant properties of the original L-ascorbic acid ring and can be used to solubilize and protect valuable organic molecules.
Proceedings of the National Academy of Sciences, 2012
Biosystems integration into an organic field-effect transistor (OFET) structure is achieved by sp... more Biosystems integration into an organic field-effect transistor (OFET) structure is achieved by spin coating phospholipid or protein layers between the gate dielectric and the organic semiconductor. An architecture directly interfacing supported biological layers to the OFET channel is proposed and, strikingly, both the electronic properties and the biointerlayer functionality are fully retained. The platform bench tests involved OFETs integrating phospholipids and bacteriorhodopsin exposed to 1-5% anesthetic doses that reveal drug-induced changes in the lipid membrane. This result challenges the current anesthetic action model relying on the so far provided evidence that doses much higher than clinically relevant ones (2.4%) do not alter lipid bilayers' structure significantly. Furthermore, a streptavidin embedding OFET shows label-free biotin electronic detection at 10 parts-per-trillion concentration level, reaching state-of-the-art fluorescent assay performances. These examples show how the proposed bioelectronic platform, besides resulting in extremely performing biosensors, can open insights into biologically relevant phenomena involving membrane weak interfacial modifications.
Switching flow and phase behavior in surfactant systems via photochemical reactions
Progress in Colloid & Polymer Science, 1996
Photochemically induced viscosity changes in dilute aqueous micellar solutions of cetyltrimethyla... more Photochemically induced viscosity changes in dilute aqueous micellar solutions of cetyltrimethylammonium bromide (CTAB) and of Triton X-100 (TRI) are brought about via the photoconversion of solubilized N-methyldiphenylamine (MDPA) to N-methylcarbazole (MC). Previously, these photorheological effects were ascribed to transformations of the micellar hydration shell. New support for this rationalization was gained from ESR-spectra of various nitroxide radical spin probes measured in the respective systems. Coupling constant variations of probes associated with the micelles indicated that MDPA is solubilized near the micelle/water interface while MC is located deeper in the micellar core. Probes residing in the bulk aqueous phase were not affected by the presence of solubilizates. Only spin probes located in the aqueous phase just outside the micelle, i.e., in the hydration layer, responded to observed macroscopic viscosity changes by accordingly varying motional correlation times. — In lyotropic liquid crystalline systems phase transitions can be induced by photochemically transforming certain solubilizates, when photoeducts induce transition temperatures distinct from those induced by the photoproducts. Series of bis-thienyl-cyclopentenes (BTCPs) (capable of photocyclization) and of hydroxystilbazolium bromides (capable of cis-trans isomerizations and dimerizations) were tested as photochemically reactive solubilizates in CTAB-water (transition nematic-isotropic), AOT-glycerol, and AOT-formamide (transition lamellar-isotropic). Shifts of transition temperatures up to 10°C upon irradiating systems contamining these solubilizates were found.
Oil-in-water microemulsions to solubilize acrylic copolymers: application in cultural heritage conservation
Progress in Colloid and Polymer Science, 2001
The principal aim of this study was the development of oil-in-water (o/w) microemulsions effectiv... more The principal aim of this study was the development of oil-in-water (o/w) microemulsions effective in the solu-bilization of acrylic copolymers. These copolymeric substances have been widely used in cultural heritage conservation since 1960. They have mainly been applied as ...
Nucleolipid bilayers: A quartz crystal microbalance and neutron reflectometry study
Colloids and Surfaces B: Biointerfaces, 2015
POP-Ade (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyladenosine) is a biocompatible anionic nucl... more POP-Ade (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyladenosine) is a biocompatible anionic nucleolipid with the DNA nucleoside, Adenosine, in the polar headgroup. We have studied the affinity of nucleic acids of different contour length, composition and structure toward supported lipid bilayers (SLB) composed of POP-Ade mixed with the zwitterionic phospholipid POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) using quartz crystal microbalance with dissipation monitoring (QCM-D) and neutron reflectometry (NR). In order to highlight the specificity of the nucleic acid interaction, the results were compared with data obtained for SLB containing the anionic phospholipid POPG (1-palmitoyl-2-oleoyl-sn-phosphatidyl-glycerol) replacing POP-Ade. Our results demonstrate that the presence of a nucleobase headgroup provides the bilayers with the ability to bind single stranded nucleic acids in a selective fashion, according to a Watson-Crick pattern. In addition the interaction with double stranded nucleic acids was strengthened. Overall, these findings represent fundamental information for the design of biocompatible DNA vectors with DNA-RNA-based amphiphiles.
The aim of the project is to verify a new liquid biofuel chain for heat production (proof of a co... more The aim of the project is to verify a new liquid biofuel chain for heat production (proof of a concept), to determine fuel specifications for pyrolysis oil (PO) in different applications and to carry out long-term combustion tests. Scientific objectives include modification of PO composition for improved stability by hot gas filtration and production of emulsions and cleaner combustion by
Structural effects of alcohol addition to sodium dodecyl sulfate micelles studied by electron spin-echo modulation of 5-doxylstearic acid spin probe
The Journal of Physical Chemistry, 1987
ABSTRACT
Alkyl chain length effects on the photoionization of N-alkylphenothiazines and sulfonated alkylphenothiazines in anionic alkyl sulfate and cationic alkyltrimethylammonium bromide micelles
The Journal of Physical Chemistry, 1991
... Young So0 Kang, Piero Baglioni,+ Hugh JD McManus, and Larry Kevan* ... 1 1985,81, 1025. (7) S... more ... Young So0 Kang, Piero Baglioni,+ Hugh JD McManus, and Larry Kevan* ... 1 1985,81, 1025. (7) Szajdzinska-Pietek, E.; Maldonado, D.; Kevan, L.; Jones, RR M. J. (8) Maldonado, R.; Kevan, L.; Szajdzinska-Pietek, E.; Jones, RR M. J. (9) Baglioni, P.; Kevan, L. J. Phys. Chem. ...
Photoionization of phenothiazinyl- and (carbazolylalkyl)trimethylammonium bromides in frozen AOT reversed micellar solutions studied by electron spin echo modulation and electron spin resonance
The Journal of Physical Chemistry, 1991
ABSTRACT
Electron spin echo modulation study of AOT reverse micelles
The Journal of Physical Chemistry, 1991
ABSTRACT
Photoionization of N,N,N',N'-tetramethylbenzidine in a mixed micelle of ionic and nonionic surfactants: electron spin-echo modulation and electron spin resonance studies
The Journal of Physical Chemistry, 1991
ABSTRACT
Photoionization of N,N,N',N'-tetramethylbenzidine in anionic-cationic mixed micelles of sodium dodecyl sulfate-dodecyltrimethylammonium chloride: electron spin resonance and electron spin echo modulation studies
The Journal of Physical Chemistry, 1988
Electron spin echo modulation (ESEM) and electron spin resonance (ESR) spectra of the photogenera... more Electron spin echo modulation (ESEM) and electron spin resonance (ESR) spectra of the photogenerated N,N,N',N'-tetramethylbenzidine cation radical (TMB/sup +/) in frozen mixed micelles of dodecyltrimethylammonium chloride (DTAC) and sodium dodecyl sulfate (SDS) have been studied as a function of the mixed micelle composition. ESEM effects due to TMB/sup +/ interactions with deuterium in DâO show a decrease of the TMB/sup
Photoreduction of alkylmethylviologens with .alpha.-tocopherol in dioctadecyldimethylammonium chloride vesicles
The Journal of Physical Chemistry, 1992
ABSTRACT Electron spin resonance (ESR) spectroscopy is used to detect the photoreduction yield of... more ABSTRACT Electron spin resonance (ESR) spectroscopy is used to detect the photoreduction yield of alkylmethylviologens (AV{sup 2+}) in rapidly frozen dioctadecyldimethylammonium chloride (DODAC) vesicles containing concentrations of α-tocopherol (major component of vitamin E) from 0 to 23 mol %. The observed radicals are alkylmethylviologen cation radicals (AV{sup +}) from photoirradiated AV{sup 2+} in DODAC vesicles without α-tocopherol. For 1-3 mol % α-tocopherol, the major radical is AV{sup +} and the minor radical is a neutral free radical of α-tocopherol (EO) which is formed by photoinduced conversion from the α-tocopherol cation radical (EH{sup +}) with DODAC vesicles acting as proton scavengers. The total ESR intensity increases with an increase of the alkyl chain length of AV{sup 2+}. The AV{sup +} intensity increases slightly with increasing α-tocopherol concentration. For over 9 mol % α-tocopherol, the major radical becomes EO, and at 17 mol % EO alone is observed. This is explained by acceleration of the photoreduction of AV{sup 2+} to AV{sup +} by electrons released from α-tocopherol and further photoreduction of AV{sup +} to AV, which is not detected by ESR spectroscopy. The photoyield for 23 mol % α-tocopherol in DODAC vesicles without AV{sup 2+} is about 2-fold more than that in hexane solution. This enhancement of photoyield suggests that DODAC may act as a proton scavenger and compartmentalize α-tocopherol to minimize back electron reaction. 26 refs., 8 figs.
Supramolecular structures formed by phospholiponucleosides: Aggregational properties and molecular recognition
Progress in Colloid and Polymer Science, 2002
ABSTRACT
A New Method for Paper Deacidification Based on Calcium Hydroxide Dispersed in Nonaqueous Media
Studies in Conservation, 2002
ABSTRACT
Electron spin-echo modulation of x-doxylstearic acid in nonionic surfactants
The Journal of Physical Chemistry, 1989
Electron spin-echo studies have been carried out for a series of x-doxylstearic acid spin probes ... more Electron spin-echo studies have been carried out for a series of x-doxylstearic acid spin probes (x-DSA, x = 5, 7, 10, 12, and 16) in frozen micellar solutions of some poly(ethylene oxide) surfactants, CââEâ, CââEâ, CâEâ, and CâEâ, and in surfactants selectively deuterated along the aliphatic chain or in the poly(ethylene oxide) groups, (CD)ââEâ, CââDâ, CâDâ, and (CD)ââEâ, in DâO
Trends in Colloid and Interface Science XVI, 2004
The preparation and structural characterization of a family of viscoelastic dispersions of borate... more The preparation and structural characterization of a family of viscoelastic dispersions of borate cross-linked, 80% hydrolyzed poly(vinyl acetate) (80PVAc) in aqueousÀorganic liquids are presented. Correlations between mechanical properties (from rheological measurements) and the degree and nature of cross-linking (from 11 B NMR spectroscopy) are reported, and the results are used to assess their potential as low-impact cleaning agents for the surfaces of paintings. Because the dispersions can be prepared at room temperature by simple procedures from readily available materials and can contain up to 50% (w/w) of an organic liquid, they offer important advantages over previously described cleaning agents that are based on fully hydrolyzed PVAc (i.e., poly(vinyl alcohol). The mechanical properties of the various aqueousÀorganic dispersions, as determined quantitatively by rheological investigations and qualitatively by their ease of removal from a solid surface (i.e., the so-called "peel-off" ability) have been tuned systematically by varying the amount of organic liquid, its structure, and the concentrations of borax and 80PVAc. The 11 B NMR studies demonstrate that the concentration of borate ions actively participating in cross-linking increases significantly with the amount of organic liquid in the mixture. The degree of cross-linking remains constant when the 80PVAc and borax concentrations are varied, as long as their ratios are kept constant. Some of the 80PVAcÀborax dispersions have been tested successfully as cleaning agents on the surface of a 16thÀ17th century oil-on-wood painting by Lodovico Cardi, "Il Cigoli", that was covered by a brown patina and on the surface of a Renaissance wall painting by Vecchietta in Santa Maria della Scala, Siena, Italy, that had a degraded polyacrylate coating from a previous conservation treatment.
Chemosphere, 2015
We studied the specific anion effect on the vitality of Artemia salina. The results are discussed... more We studied the specific anion effect on the vitality of Artemia salina. The results are discussed in terms of the Hofmeister series. Strong kosmotropes and chaotropes have severe adverse effects on Artemia salina. The effect depends on the salt physico-chemical properties. The stability of oxygen bubbles and the ion adsorption partly explain the effects.
Bio-Crude-Oil/Diesel Oil Emulsification: main Achievements of the Emulsification Process and Preliminary Results of Tests on Diesel engine
Progress in Thermochemical Biomass Conversion, 2001
ABSTRACT
Nature nanotechnology, Jan 9, 2015
Tackling the degradation of cultural heritage requires a global effort. We call on all material s... more Tackling the degradation of cultural heritage requires a global effort. We call on all material scientists to develop new nanomaterials and methods for the preservation of artwork.
The Journal of …, Jan 1, 2007
A new double chained surfactant, 2-octyl-dodecanoyl-6-O-ascorbic acid (8ASC10), with a L-ascorbic... more A new double chained surfactant, 2-octyl-dodecanoyl-6-O-ascorbic acid (8ASC10), with a L-ascorbic acid unit as the polar headgroup was synthesized for the first time. The behavior of the compound in the dry solid state has been characterized through DSC, XRD, and SAXS measurements. The surfactant forms stable viscous organogels in the presence of suitable organic solvents and also water-induced organogels upon addition of water to the organogel. These mixtures show shear-thinning properties and are birefringent. The behavior and properties of the organogels have been studied through rheology, DSC, and SAXS experiments. The organogels possess the same antioxidant properties of the original L-ascorbic acid ring and can be used to solubilize and protect valuable organic molecules.
Proceedings of the National Academy of Sciences, 2012
Biosystems integration into an organic field-effect transistor (OFET) structure is achieved by sp... more Biosystems integration into an organic field-effect transistor (OFET) structure is achieved by spin coating phospholipid or protein layers between the gate dielectric and the organic semiconductor. An architecture directly interfacing supported biological layers to the OFET channel is proposed and, strikingly, both the electronic properties and the biointerlayer functionality are fully retained. The platform bench tests involved OFETs integrating phospholipids and bacteriorhodopsin exposed to 1-5% anesthetic doses that reveal drug-induced changes in the lipid membrane. This result challenges the current anesthetic action model relying on the so far provided evidence that doses much higher than clinically relevant ones (2.4%) do not alter lipid bilayers' structure significantly. Furthermore, a streptavidin embedding OFET shows label-free biotin electronic detection at 10 parts-per-trillion concentration level, reaching state-of-the-art fluorescent assay performances. These examples show how the proposed bioelectronic platform, besides resulting in extremely performing biosensors, can open insights into biologically relevant phenomena involving membrane weak interfacial modifications.
Switching flow and phase behavior in surfactant systems via photochemical reactions
Progress in Colloid & Polymer Science, 1996
Photochemically induced viscosity changes in dilute aqueous micellar solutions of cetyltrimethyla... more Photochemically induced viscosity changes in dilute aqueous micellar solutions of cetyltrimethylammonium bromide (CTAB) and of Triton X-100 (TRI) are brought about via the photoconversion of solubilized N-methyldiphenylamine (MDPA) to N-methylcarbazole (MC). Previously, these photorheological effects were ascribed to transformations of the micellar hydration shell. New support for this rationalization was gained from ESR-spectra of various nitroxide radical spin probes measured in the respective systems. Coupling constant variations of probes associated with the micelles indicated that MDPA is solubilized near the micelle/water interface while MC is located deeper in the micellar core. Probes residing in the bulk aqueous phase were not affected by the presence of solubilizates. Only spin probes located in the aqueous phase just outside the micelle, i.e., in the hydration layer, responded to observed macroscopic viscosity changes by accordingly varying motional correlation times. — In lyotropic liquid crystalline systems phase transitions can be induced by photochemically transforming certain solubilizates, when photoeducts induce transition temperatures distinct from those induced by the photoproducts. Series of bis-thienyl-cyclopentenes (BTCPs) (capable of photocyclization) and of hydroxystilbazolium bromides (capable of cis-trans isomerizations and dimerizations) were tested as photochemically reactive solubilizates in CTAB-water (transition nematic-isotropic), AOT-glycerol, and AOT-formamide (transition lamellar-isotropic). Shifts of transition temperatures up to 10°C upon irradiating systems contamining these solubilizates were found.
Oil-in-water microemulsions to solubilize acrylic copolymers: application in cultural heritage conservation
Progress in Colloid and Polymer Science, 2001
The principal aim of this study was the development of oil-in-water (o/w) microemulsions effectiv... more The principal aim of this study was the development of oil-in-water (o/w) microemulsions effective in the solu-bilization of acrylic copolymers. These copolymeric substances have been widely used in cultural heritage conservation since 1960. They have mainly been applied as ...
Nucleolipid bilayers: A quartz crystal microbalance and neutron reflectometry study
Colloids and Surfaces B: Biointerfaces, 2015
POP-Ade (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyladenosine) is a biocompatible anionic nucl... more POP-Ade (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyladenosine) is a biocompatible anionic nucleolipid with the DNA nucleoside, Adenosine, in the polar headgroup. We have studied the affinity of nucleic acids of different contour length, composition and structure toward supported lipid bilayers (SLB) composed of POP-Ade mixed with the zwitterionic phospholipid POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) using quartz crystal microbalance with dissipation monitoring (QCM-D) and neutron reflectometry (NR). In order to highlight the specificity of the nucleic acid interaction, the results were compared with data obtained for SLB containing the anionic phospholipid POPG (1-palmitoyl-2-oleoyl-sn-phosphatidyl-glycerol) replacing POP-Ade. Our results demonstrate that the presence of a nucleobase headgroup provides the bilayers with the ability to bind single stranded nucleic acids in a selective fashion, according to a Watson-Crick pattern. In addition the interaction with double stranded nucleic acids was strengthened. Overall, these findings represent fundamental information for the design of biocompatible DNA vectors with DNA-RNA-based amphiphiles.
The aim of the project is to verify a new liquid biofuel chain for heat production (proof of a co... more The aim of the project is to verify a new liquid biofuel chain for heat production (proof of a concept), to determine fuel specifications for pyrolysis oil (PO) in different applications and to carry out long-term combustion tests. Scientific objectives include modification of PO composition for improved stability by hot gas filtration and production of emulsions and cleaner combustion by
Structural effects of alcohol addition to sodium dodecyl sulfate micelles studied by electron spin-echo modulation of 5-doxylstearic acid spin probe
The Journal of Physical Chemistry, 1987
ABSTRACT
Alkyl chain length effects on the photoionization of N-alkylphenothiazines and sulfonated alkylphenothiazines in anionic alkyl sulfate and cationic alkyltrimethylammonium bromide micelles
The Journal of Physical Chemistry, 1991
... Young So0 Kang, Piero Baglioni,+ Hugh JD McManus, and Larry Kevan* ... 1 1985,81, 1025. (7) S... more ... Young So0 Kang, Piero Baglioni,+ Hugh JD McManus, and Larry Kevan* ... 1 1985,81, 1025. (7) Szajdzinska-Pietek, E.; Maldonado, D.; Kevan, L.; Jones, RR M. J. (8) Maldonado, R.; Kevan, L.; Szajdzinska-Pietek, E.; Jones, RR M. J. (9) Baglioni, P.; Kevan, L. J. Phys. Chem. ...
Photoionization of phenothiazinyl- and (carbazolylalkyl)trimethylammonium bromides in frozen AOT reversed micellar solutions studied by electron spin echo modulation and electron spin resonance
The Journal of Physical Chemistry, 1991
ABSTRACT
Electron spin echo modulation study of AOT reverse micelles
The Journal of Physical Chemistry, 1991
ABSTRACT
Photoionization of N,N,N',N'-tetramethylbenzidine in a mixed micelle of ionic and nonionic surfactants: electron spin-echo modulation and electron spin resonance studies
The Journal of Physical Chemistry, 1991
ABSTRACT
Photoionization of N,N,N',N'-tetramethylbenzidine in anionic-cationic mixed micelles of sodium dodecyl sulfate-dodecyltrimethylammonium chloride: electron spin resonance and electron spin echo modulation studies
The Journal of Physical Chemistry, 1988
Electron spin echo modulation (ESEM) and electron spin resonance (ESR) spectra of the photogenera... more Electron spin echo modulation (ESEM) and electron spin resonance (ESR) spectra of the photogenerated N,N,N',N'-tetramethylbenzidine cation radical (TMB/sup +/) in frozen mixed micelles of dodecyltrimethylammonium chloride (DTAC) and sodium dodecyl sulfate (SDS) have been studied as a function of the mixed micelle composition. ESEM effects due to TMB/sup +/ interactions with deuterium in DâO show a decrease of the TMB/sup
Photoreduction of alkylmethylviologens with .alpha.-tocopherol in dioctadecyldimethylammonium chloride vesicles
The Journal of Physical Chemistry, 1992
ABSTRACT Electron spin resonance (ESR) spectroscopy is used to detect the photoreduction yield of... more ABSTRACT Electron spin resonance (ESR) spectroscopy is used to detect the photoreduction yield of alkylmethylviologens (AV{sup 2+}) in rapidly frozen dioctadecyldimethylammonium chloride (DODAC) vesicles containing concentrations of α-tocopherol (major component of vitamin E) from 0 to 23 mol %. The observed radicals are alkylmethylviologen cation radicals (AV{sup +}) from photoirradiated AV{sup 2+} in DODAC vesicles without α-tocopherol. For 1-3 mol % α-tocopherol, the major radical is AV{sup +} and the minor radical is a neutral free radical of α-tocopherol (EO) which is formed by photoinduced conversion from the α-tocopherol cation radical (EH{sup +}) with DODAC vesicles acting as proton scavengers. The total ESR intensity increases with an increase of the alkyl chain length of AV{sup 2+}. The AV{sup +} intensity increases slightly with increasing α-tocopherol concentration. For over 9 mol % α-tocopherol, the major radical becomes EO, and at 17 mol % EO alone is observed. This is explained by acceleration of the photoreduction of AV{sup 2+} to AV{sup +} by electrons released from α-tocopherol and further photoreduction of AV{sup +} to AV, which is not detected by ESR spectroscopy. The photoyield for 23 mol % α-tocopherol in DODAC vesicles without AV{sup 2+} is about 2-fold more than that in hexane solution. This enhancement of photoyield suggests that DODAC may act as a proton scavenger and compartmentalize α-tocopherol to minimize back electron reaction. 26 refs., 8 figs.
Supramolecular structures formed by phospholiponucleosides: Aggregational properties and molecular recognition
Progress in Colloid and Polymer Science, 2002
ABSTRACT
A New Method for Paper Deacidification Based on Calcium Hydroxide Dispersed in Nonaqueous Media
Studies in Conservation, 2002
ABSTRACT
Electron spin-echo modulation of x-doxylstearic acid in nonionic surfactants
The Journal of Physical Chemistry, 1989
Electron spin-echo studies have been carried out for a series of x-doxylstearic acid spin probes ... more Electron spin-echo studies have been carried out for a series of x-doxylstearic acid spin probes (x-DSA, x = 5, 7, 10, 12, and 16) in frozen micellar solutions of some poly(ethylene oxide) surfactants, CââEâ, CââEâ, CâEâ, and CâEâ, and in surfactants selectively deuterated along the aliphatic chain or in the poly(ethylene oxide) groups, (CD)ââEâ, CââDâ, CâDâ, and (CD)ââEâ, in DâO
Trends in Colloid and Interface Science XVI, 2004
The preparation and structural characterization of a family of viscoelastic dispersions of borate... more The preparation and structural characterization of a family of viscoelastic dispersions of borate cross-linked, 80% hydrolyzed poly(vinyl acetate) (80PVAc) in aqueousÀorganic liquids are presented. Correlations between mechanical properties (from rheological measurements) and the degree and nature of cross-linking (from 11 B NMR spectroscopy) are reported, and the results are used to assess their potential as low-impact cleaning agents for the surfaces of paintings. Because the dispersions can be prepared at room temperature by simple procedures from readily available materials and can contain up to 50% (w/w) of an organic liquid, they offer important advantages over previously described cleaning agents that are based on fully hydrolyzed PVAc (i.e., poly(vinyl alcohol). The mechanical properties of the various aqueousÀorganic dispersions, as determined quantitatively by rheological investigations and qualitatively by their ease of removal from a solid surface (i.e., the so-called "peel-off" ability) have been tuned systematically by varying the amount of organic liquid, its structure, and the concentrations of borax and 80PVAc. The 11 B NMR studies demonstrate that the concentration of borate ions actively participating in cross-linking increases significantly with the amount of organic liquid in the mixture. The degree of cross-linking remains constant when the 80PVAc and borax concentrations are varied, as long as their ratios are kept constant. Some of the 80PVAcÀborax dispersions have been tested successfully as cleaning agents on the surface of a 16thÀ17th century oil-on-wood painting by Lodovico Cardi, "Il Cigoli", that was covered by a brown patina and on the surface of a Renaissance wall painting by Vecchietta in Santa Maria della Scala, Siena, Italy, that had a degraded polyacrylate coating from a previous conservation treatment.
Chemosphere, 2015
We studied the specific anion effect on the vitality of Artemia salina. The results are discussed... more We studied the specific anion effect on the vitality of Artemia salina. The results are discussed in terms of the Hofmeister series. Strong kosmotropes and chaotropes have severe adverse effects on Artemia salina. The effect depends on the salt physico-chemical properties. The stability of oxygen bubbles and the ion adsorption partly explain the effects.
Bio-Crude-Oil/Diesel Oil Emulsification: main Achievements of the Emulsification Process and Preliminary Results of Tests on Diesel engine
Progress in Thermochemical Biomass Conversion, 2001
ABSTRACT
Nature nanotechnology, Jan 9, 2015
Tackling the degradation of cultural heritage requires a global effort. We call on all material s... more Tackling the degradation of cultural heritage requires a global effort. We call on all material scientists to develop new nanomaterials and methods for the preservation of artwork.