Cristian Boscornea - Academia.edu (original) (raw)
Papers by Cristian Boscornea
Polymers
Fireproof inorganic coatings based on sodium silicate solution with intumescent additions were pr... more Fireproof inorganic coatings based on sodium silicate solution with intumescent additions were prepared and tested to assess their ability to limit the negative effect of a fire. The intumescent materials were obtained by the alkali activation of waste glass powder (obtained by the grinding of recycled soda-lime culet) and slag (waste resulting from the metallurgical industry). The replacement of talc (used as filler in paint formulation) with the intumescent materials obtained by the alkaline activation of waste glass powder (WGP), determined an increase in the intumescence coefficient (up to 65%) and decreased the activation temperature of this process. To evaluate these coatings’ abilities to prevent or delay the temperature increase in metal structures, the paints were applied on steel plates and tested in direct contact with the flame of a butane burner for 60 min. The coatings prevented the increase in the steel substrate temperature over one considered critical (500°C) for st...
The paper present the synthesis and characterization of a novel phthalocyanine compound, obtained... more The paper present the synthesis and characterization of a novel phthalocyanine compound, obtained by binding two units of Zn phthalocyanin tetracarboxylic acid via a spacer with pentaerythritol structure. The synthesized compound was analyzed in terms of its photophysical properties, and of the interaction with the TiO2 substrate. Experimental data show a significant increase of light absorption in the visible range and an improved fit on TiO2, the compound being a good candidate for use in Gratzel type solar cells.
We report the full electrical characterization of a dye-sensitized solar cell (DSSC), in which th... more We report the full electrical characterization of a dye-sensitized solar cell (DSSC), in which the photovoltaic (PV) effect can be observed, under a radiation field closely resembling the AM 1.5 solar spectrum, together with an estimation of the variation of the determined parameters in the 300-400K temperature ranges, based on the electrical model and theoretical estimation techniques. The current-voltage characteristic serves as both a proof-of-existence for the PV effect and a source for electrical parameter extraction. The devices exhibits promising efficiency and fill factors if operated at convenient temperatures.
![Research paper thumbnail of Influence of the chemical structure and solvent polarity on the fluorescence of 3-aryl-7-benzoyl-pyrrolo [1,2-c]pyrimidines](https://attachments.academia-assets.com/100566487/thumbnails/1.jpg)
](Dyes and Pigments, 2019
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
![Research paper thumbnail of Synthesis and fluorescence of new 3-biphenylpyrrolo[1,2-c]pyrimidines](https://attachments.academia-assets.com/100566481/thumbnails/1.jpg)
](Arabian Journal of Chemistry, 2017
New pyrrolo[1,2-c]pyrimidines derivates having a biphenyl moiety at position 3 have been synthesi... more New pyrrolo[1,2-c]pyrimidines derivates having a biphenyl moiety at position 3 have been synthesized by 1,3-dipolar cycloaddition of their corresponding N-ylides with activated alkynes. FTIR, 1 H and 13 C NMR spectroscopy and elemental analysis have been used to characterize the structures of the new nine pyrrolo[1,2-c]pyrimidine derivates. Absorption and fluorescence spectra have been recorded. The appropriate solvent for the photoluminescence properties of the studied compounds has been found to be chloroform:acetonitrile mixture (1:1). The main spectral features such as molar extinction coefficients (e), Stokes shifts, quantum yields using quinine sulphate as standard, fluorescence quenching in the presence of benzoquinone and Stern-Volmer constants have been calculated. The substituent effects on intensity of absorption, maximum absorbance wavelengths and fluorescence parameters have been discussed. The highest quantum yield value was found for ethyl 3-(4-biphenylyl)-7-(3,4-dimethoxybenzoyl)pyrrolo[1,2-c]pyrimidine-5-carboxylate (0.55). The obtained results suggest that the studied compounds are promising candidates for future study in order to evaluate their use in practical applications in fluorescent chemical sensors.
MATERIALE PLASTICE
The influence of various additives, like salts, alkohols, surfactants and water-miscible organic ... more The influence of various additives, like salts, alkohols, surfactants and water-miscible organic solvents, upon the cloud point of α,ω-(2-hydroxyethoxy) oligo(propylene oxide) in aqueous solutions was investigated for the first time. The results showed that NaH2PO4, NaCl, NaBr, NaI, 1-butanol, ethylene glycol and dimethylsulfoxide decreased the cloud point, while 1,2-propylene glycol, sodium dodecylsulfate, nonylphenyl ethoxylated with 9 moles of ethylene oxide and dioxane increased it. Addition of N,N-dimethylformamide practically had no influence upon the cloud point on the concentration interval investigated. The LCST of α,ω-(2-hydroxyethoxy) oligo(propylene oxide) in aqueous solution was also determined and it was found equal to 19°C.
Chemical Engineering Transactions, 2012
A solution to improve the students' interest for science study assumes ICT tools introduction in ... more A solution to improve the students' interest for science study assumes ICT tools introduction in the teaching process. The SOP HRD 61839 project "Looking Towards the Future-Professional Training of the Teaching Staff to Use Modern Digital Resources in Efficiently Teaching of Chemistry eChemistry", financed from the European Social Fund aims to develop ICT skills for professors who teach chemistry and technology-related subjects in the K-12 system. Even if computer usage in the learningteaching processes is very successful, putting it into practice is rare in Romania. The project included two training components: a five-day module for developing basic IT skills and an eleven-day module for applying the newly acquired skills in chemistry teaching. A set of educational pilot resources were developed and used intensively during the training sessions organized in all 41 counties and capital of Romania. Although the project has its own learning content management system suitable for online and offline training activities, all sessions were face-to-face organized in order to offer a maximum tutorial support to participants. The digital resources are focused on main subjects from organic, inorganic, analytic, physical chemistry and electrochemistry, being presented to the target group by trainers from the University Politehnica of Bucharest and University Politehnica of Timisoara. Since July 2011 until May 2012 more than 2500 trainees completed the two training programs. eChemistry is supposed to bring together people who experience similar difficulties in their teaching activity and are eager for finding solutions to teach more, better and faster.
Molecular Crystals and Liquid Crystals, 2010
In the large family of polymers, the azobenzene derivatives represent one fascinating materials c... more In the large family of polymers, the azobenzene derivatives represent one fascinating materials class, along with stylbene and azomethinic derivatives. This interest is explained by combination of the properties of anisotropy with the photoinduced behaviors. The photoinduced ...
Molecules
Currently there is a drive towards the minimisation and reclamation of valuable materials from th... more Currently there is a drive towards the minimisation and reclamation of valuable materials from the waste products of the food and beverage industry. This can be achieved through the extraction of residual nutraceuticals from such materials. Tomato pomace contains carotenoids and other chemicals which can be extracted directly into edible oils to improve the health-giving properties of such oils. We report here a novel green solvent, fatty acid ethyl esters (FAEE), which is significantly more effective than sunflower oil and hexane for the extraction of lycopene and beta-carotene from tomato skin waste. FAEE are a non-toxic renewable resource that is environmentally friendly and to our knowledge has never been used as a vegetal extraction fluid. The efficiency of FAEE extraction was significantly improved relative to both sunflower oil and hexane under ultrasound-assisted extraction (UAE) conditions. In addition, FAEE have the additional and significant advantage that once enriched w...
A fost studiată sinteza unor compuşi de concepţie originală obtinuţi prin depunerea unor coloranţ... more A fost studiată sinteza unor compuşi de concepţie originală obtinuţi prin depunerea unor coloranţi ftalocianinici pe suport de ferită. Prepararea lor implică reacţii de tip template între ftalocianina de litiu sau liberă de metal cu diverse ferite. Compozitele sintetizate au fost analizate prin spectroscopie Mössbauer. Compuşii sintetizaţi au fost testaţi din punct de vedere al proprietăţilor catalitice în reacţia de oxidare a ciclohexanului cu aer. The synthesis of some original compounds based on phthalocyanines deposed on various ferrites was studied. The preparation of the compounds consisted in the template type reaction between metal free phthalocyanine or lithium phthalocyanine and various ferrites. The characterization of the synthesized compounds was made using Mössbauer spectroscopy. The synthesized compounds were submitted to a catalytic test in the cyclohexane oxidation reaction with air.
SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY, 2002
The paper presents the synthetic routes for obtaining some organic semiconductors and their chara... more The paper presents the synthetic routes for obtaining some organic semiconductors and their characterization in order to use in thin film deposition for gas sensing devices. An original technique was used to control the molecular weight of polymeric phthalocyanine. We have fabricated devices consisting of evaporated thin films of copper, nickel, and iron phthalocyanines onto interdigital electrodes and estimated the electrical conductivity by in-situ measurements. The films were evaporated onto substrates (gold or aluminum) which were entirely integrated in the standard CMOS (capacitor metal oxide semiconductor) technology. The objectives of this work were to improve the synthesis methods of organic metal-complex tetraizoindoles and their polymers and to evaluate their electrical response and thermal stability as evaporated thin films. We have also investigated the variation of polymers conductivity and sublimation yield with the average molecular weight. We found that for polymeric...
Proceedings, 2020
The natural dyes extracted from plants are efficient sensitizers for TiO2 particles involved in p... more The natural dyes extracted from plants are efficient sensitizers for TiO2 particles involved in photocatalytic processes [...]
Revista de Chimie, 2008
Metallo- phtalocyanines were obtained in good yields by the solvothermal method, a new and origin... more Metallo- phtalocyanines were obtained in good yields by the solvothermal method, a new and original synthesis method, optimized in real laboratory conditions. The structures were characterized by elemental analysis, UV-VIS and IR spectroscopy. Some of the compounds (iron phthalocyanine) were assigned by M�ssbauer spectroscopy.
Journal of Nanomaterials, 2015
The aim of the present study consists in the obtaining of a hybrid material film, obtained using ... more The aim of the present study consists in the obtaining of a hybrid material film, obtained using TiO2P25 and silver nanoparticles (AgNPs). The film manufacturing process involved realization of physical mixtures of TiO2P25 and AgNPs dispersions. The size distribution of the AgNPs proved to be a key factor determining the photodegradation activity of the materials measured using methyl orange. The best result was 33% degradation of methyl orange (MO) after 150 min. The second approach was the generation of AgNPs on the surface of TiO2P25. The obtained hybrid material presents photocatalytic activity of 45% MO degradation after 150 min. The developed materials were characterized by UV-VIS, SEM, and DLS analyses.
Polymers
Fireproof inorganic coatings based on sodium silicate solution with intumescent additions were pr... more Fireproof inorganic coatings based on sodium silicate solution with intumescent additions were prepared and tested to assess their ability to limit the negative effect of a fire. The intumescent materials were obtained by the alkali activation of waste glass powder (obtained by the grinding of recycled soda-lime culet) and slag (waste resulting from the metallurgical industry). The replacement of talc (used as filler in paint formulation) with the intumescent materials obtained by the alkaline activation of waste glass powder (WGP), determined an increase in the intumescence coefficient (up to 65%) and decreased the activation temperature of this process. To evaluate these coatings’ abilities to prevent or delay the temperature increase in metal structures, the paints were applied on steel plates and tested in direct contact with the flame of a butane burner for 60 min. The coatings prevented the increase in the steel substrate temperature over one considered critical (500°C) for st...
The paper present the synthesis and characterization of a novel phthalocyanine compound, obtained... more The paper present the synthesis and characterization of a novel phthalocyanine compound, obtained by binding two units of Zn phthalocyanin tetracarboxylic acid via a spacer with pentaerythritol structure. The synthesized compound was analyzed in terms of its photophysical properties, and of the interaction with the TiO2 substrate. Experimental data show a significant increase of light absorption in the visible range and an improved fit on TiO2, the compound being a good candidate for use in Gratzel type solar cells.
We report the full electrical characterization of a dye-sensitized solar cell (DSSC), in which th... more We report the full electrical characterization of a dye-sensitized solar cell (DSSC), in which the photovoltaic (PV) effect can be observed, under a radiation field closely resembling the AM 1.5 solar spectrum, together with an estimation of the variation of the determined parameters in the 300-400K temperature ranges, based on the electrical model and theoretical estimation techniques. The current-voltage characteristic serves as both a proof-of-existence for the PV effect and a source for electrical parameter extraction. The devices exhibits promising efficiency and fill factors if operated at convenient temperatures.
Dyes and Pigments, 2019
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Arabian Journal of Chemistry, 2017
New pyrrolo[1,2-c]pyrimidines derivates having a biphenyl moiety at position 3 have been synthesi... more New pyrrolo[1,2-c]pyrimidines derivates having a biphenyl moiety at position 3 have been synthesized by 1,3-dipolar cycloaddition of their corresponding N-ylides with activated alkynes. FTIR, 1 H and 13 C NMR spectroscopy and elemental analysis have been used to characterize the structures of the new nine pyrrolo[1,2-c]pyrimidine derivates. Absorption and fluorescence spectra have been recorded. The appropriate solvent for the photoluminescence properties of the studied compounds has been found to be chloroform:acetonitrile mixture (1:1). The main spectral features such as molar extinction coefficients (e), Stokes shifts, quantum yields using quinine sulphate as standard, fluorescence quenching in the presence of benzoquinone and Stern-Volmer constants have been calculated. The substituent effects on intensity of absorption, maximum absorbance wavelengths and fluorescence parameters have been discussed. The highest quantum yield value was found for ethyl 3-(4-biphenylyl)-7-(3,4-dimethoxybenzoyl)pyrrolo[1,2-c]pyrimidine-5-carboxylate (0.55). The obtained results suggest that the studied compounds are promising candidates for future study in order to evaluate their use in practical applications in fluorescent chemical sensors.
MATERIALE PLASTICE
The influence of various additives, like salts, alkohols, surfactants and water-miscible organic ... more The influence of various additives, like salts, alkohols, surfactants and water-miscible organic solvents, upon the cloud point of α,ω-(2-hydroxyethoxy) oligo(propylene oxide) in aqueous solutions was investigated for the first time. The results showed that NaH2PO4, NaCl, NaBr, NaI, 1-butanol, ethylene glycol and dimethylsulfoxide decreased the cloud point, while 1,2-propylene glycol, sodium dodecylsulfate, nonylphenyl ethoxylated with 9 moles of ethylene oxide and dioxane increased it. Addition of N,N-dimethylformamide practically had no influence upon the cloud point on the concentration interval investigated. The LCST of α,ω-(2-hydroxyethoxy) oligo(propylene oxide) in aqueous solution was also determined and it was found equal to 19°C.
Chemical Engineering Transactions, 2012
A solution to improve the students' interest for science study assumes ICT tools introduction in ... more A solution to improve the students' interest for science study assumes ICT tools introduction in the teaching process. The SOP HRD 61839 project "Looking Towards the Future-Professional Training of the Teaching Staff to Use Modern Digital Resources in Efficiently Teaching of Chemistry eChemistry", financed from the European Social Fund aims to develop ICT skills for professors who teach chemistry and technology-related subjects in the K-12 system. Even if computer usage in the learningteaching processes is very successful, putting it into practice is rare in Romania. The project included two training components: a five-day module for developing basic IT skills and an eleven-day module for applying the newly acquired skills in chemistry teaching. A set of educational pilot resources were developed and used intensively during the training sessions organized in all 41 counties and capital of Romania. Although the project has its own learning content management system suitable for online and offline training activities, all sessions were face-to-face organized in order to offer a maximum tutorial support to participants. The digital resources are focused on main subjects from organic, inorganic, analytic, physical chemistry and electrochemistry, being presented to the target group by trainers from the University Politehnica of Bucharest and University Politehnica of Timisoara. Since July 2011 until May 2012 more than 2500 trainees completed the two training programs. eChemistry is supposed to bring together people who experience similar difficulties in their teaching activity and are eager for finding solutions to teach more, better and faster.
Molecular Crystals and Liquid Crystals, 2010
In the large family of polymers, the azobenzene derivatives represent one fascinating materials c... more In the large family of polymers, the azobenzene derivatives represent one fascinating materials class, along with stylbene and azomethinic derivatives. This interest is explained by combination of the properties of anisotropy with the photoinduced behaviors. The photoinduced ...
Molecules
Currently there is a drive towards the minimisation and reclamation of valuable materials from th... more Currently there is a drive towards the minimisation and reclamation of valuable materials from the waste products of the food and beverage industry. This can be achieved through the extraction of residual nutraceuticals from such materials. Tomato pomace contains carotenoids and other chemicals which can be extracted directly into edible oils to improve the health-giving properties of such oils. We report here a novel green solvent, fatty acid ethyl esters (FAEE), which is significantly more effective than sunflower oil and hexane for the extraction of lycopene and beta-carotene from tomato skin waste. FAEE are a non-toxic renewable resource that is environmentally friendly and to our knowledge has never been used as a vegetal extraction fluid. The efficiency of FAEE extraction was significantly improved relative to both sunflower oil and hexane under ultrasound-assisted extraction (UAE) conditions. In addition, FAEE have the additional and significant advantage that once enriched w...
A fost studiată sinteza unor compuşi de concepţie originală obtinuţi prin depunerea unor coloranţ... more A fost studiată sinteza unor compuşi de concepţie originală obtinuţi prin depunerea unor coloranţi ftalocianinici pe suport de ferită. Prepararea lor implică reacţii de tip template între ftalocianina de litiu sau liberă de metal cu diverse ferite. Compozitele sintetizate au fost analizate prin spectroscopie Mössbauer. Compuşii sintetizaţi au fost testaţi din punct de vedere al proprietăţilor catalitice în reacţia de oxidare a ciclohexanului cu aer. The synthesis of some original compounds based on phthalocyanines deposed on various ferrites was studied. The preparation of the compounds consisted in the template type reaction between metal free phthalocyanine or lithium phthalocyanine and various ferrites. The characterization of the synthesized compounds was made using Mössbauer spectroscopy. The synthesized compounds were submitted to a catalytic test in the cyclohexane oxidation reaction with air.
SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY, 2002
The paper presents the synthetic routes for obtaining some organic semiconductors and their chara... more The paper presents the synthetic routes for obtaining some organic semiconductors and their characterization in order to use in thin film deposition for gas sensing devices. An original technique was used to control the molecular weight of polymeric phthalocyanine. We have fabricated devices consisting of evaporated thin films of copper, nickel, and iron phthalocyanines onto interdigital electrodes and estimated the electrical conductivity by in-situ measurements. The films were evaporated onto substrates (gold or aluminum) which were entirely integrated in the standard CMOS (capacitor metal oxide semiconductor) technology. The objectives of this work were to improve the synthesis methods of organic metal-complex tetraizoindoles and their polymers and to evaluate their electrical response and thermal stability as evaporated thin films. We have also investigated the variation of polymers conductivity and sublimation yield with the average molecular weight. We found that for polymeric...
Proceedings, 2020
The natural dyes extracted from plants are efficient sensitizers for TiO2 particles involved in p... more The natural dyes extracted from plants are efficient sensitizers for TiO2 particles involved in photocatalytic processes [...]
Revista de Chimie, 2008
Metallo- phtalocyanines were obtained in good yields by the solvothermal method, a new and origin... more Metallo- phtalocyanines were obtained in good yields by the solvothermal method, a new and original synthesis method, optimized in real laboratory conditions. The structures were characterized by elemental analysis, UV-VIS and IR spectroscopy. Some of the compounds (iron phthalocyanine) were assigned by M�ssbauer spectroscopy.
Journal of Nanomaterials, 2015
The aim of the present study consists in the obtaining of a hybrid material film, obtained using ... more The aim of the present study consists in the obtaining of a hybrid material film, obtained using TiO2P25 and silver nanoparticles (AgNPs). The film manufacturing process involved realization of physical mixtures of TiO2P25 and AgNPs dispersions. The size distribution of the AgNPs proved to be a key factor determining the photodegradation activity of the materials measured using methyl orange. The best result was 33% degradation of methyl orange (MO) after 150 min. The second approach was the generation of AgNPs on the surface of TiO2P25. The obtained hybrid material presents photocatalytic activity of 45% MO degradation after 150 min. The developed materials were characterized by UV-VIS, SEM, and DLS analyses.