2018 |
Gomez-Jeria, J S; Clavijo, E; Gutierrez, S An Infrared, Sem and Xrf Study of the Paper of a 1588 Spanish Book Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (4), pp. 1581-1590, 2018, ISSN: 0975-8585. Resumen | Enlaces | BibTeX | Etiquetas: alum, analysis, archeology, cellulose, conservation, ft-ir gelatin, infrared margins paper postage potassium rags, sem, spain, spectra, spectroscopy, stamps, xrf @article{RN414, title = {An Infrared, Sem and Xrf Study of the Paper of a 1588 Spanish Book}, author = { J.S. Gomez-Jeria and E. Clavijo and S. Gutierrez}, url = {/brokenurl#<Go to ISI>://WOS:000438848100213}, issn = {0975-8585}, year = {2018}, date = {2018-01-01}, journal = {Research Journal of Pharmaceutical Biological and Chemical Sciences}, volume = {9}, number = {4}, pages = {1581-1590}, abstract = {An infrared, scanning electron microscopy and X-ray fluorescence study was performed on the Spanish book entitled Treated of the True and False Prophecy printed in Segovia during 1588. Three small samples were taken from the margins of three pages. Two of them belong to the original book while the third one is from a page added later during the binding of the book. The first result is that the paper is contaminated with numerous metallic elements. The distribution of these contaminants in the three samples suggests that this process began after the binding of the book. The carbonate moiety of the calcium carbonate seems to have disappeared with the passing of time transformed in carbon dioxide. Al, K and S, components of potassium alum are detected by SEM and XRF analyses. Gelatin seems to be present because some IR bands of proline suggest that. There is an unsolved problem with some IR bands because of the fact that they can be ascribed to two different entities.}, keywords = {alum, analysis, archeology, cellulose, conservation, ft-ir gelatin, infrared margins paper postage potassium rags, sem, spain, spectra, spectroscopy, stamps, xrf}, pubstate = {published}, tppubtype = {article} } An infrared, scanning electron microscopy and X-ray fluorescence study was performed on the Spanish book entitled Treated of the True and False Prophecy printed in Segovia during 1588. Three small samples were taken from the margins of three pages. Two of them belong to the original book while the third one is from a page added later during the binding of the book. The first result is that the paper is contaminated with numerous metallic elements. The distribution of these contaminants in the three samples suggests that this process began after the binding of the book. The carbonate moiety of the calcium carbonate seems to have disappeared with the passing of time transformed in carbon dioxide. Al, K and S, components of potassium alum are detected by SEM and XRF analyses. Gelatin seems to be present because some IR bands of proline suggest that. There is an unsolved problem with some IR bands because of the fact that they can be ascribed to two different entities. |
Gomez-Jeria, J S; Clavijo, E; Gutierrez, S An Infrared and Sem Study of the Margins of Some Estonian Postage Stamps Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (3), pp. 1258-1279, 2018, ISSN: 0975-8585. Resumen | Enlaces | BibTeX | Etiquetas: archeology, archeophilately, cellulose, electron estonia, infrared microscopy, philately postage scanning sem, spectra, stamps @article{RN412, title = {An Infrared and Sem Study of the Margins of Some Estonian Postage Stamps}, author = { J.S. Gomez-Jeria and E. Clavijo and S. Gutierrez}, url = {/brokenurl#<Go to ISI>://WOS:000438847100169}, issn = {0975-8585}, year = {2018}, date = {2018-01-01}, journal = {Research Journal of Pharmaceutical Biological and Chemical Sciences}, volume = {9}, number = {3}, pages = {1258-1279}, abstract = {Infrared spectroscopy and scanning electron microscopy (SEM) studies were performed on the margins of a set of eighteen Estonian postage stamps dated between 1918 and 1924. SEM results showed the presence of Al, Si and Zn in the samples in different combinations. Two stamps contain kaolin and one ZnO. We could not find a clear relationship between the structure of the IR spectrum and the assumed geographical origin of the papers, but the need to accumulate a large set of results to use statistical methods is clear.}, keywords = {archeology, archeophilately, cellulose, electron estonia, infrared microscopy, philately postage scanning sem, spectra, stamps}, pubstate = {published}, tppubtype = {article} } Infrared spectroscopy and scanning electron microscopy (SEM) studies were performed on the margins of a set of eighteen Estonian postage stamps dated between 1918 and 1924. SEM results showed the presence of Al, Si and Zn in the samples in different combinations. Two stamps contain kaolin and one ZnO. We could not find a clear relationship between the structure of the IR spectrum and the assumed geographical origin of the papers, but the need to accumulate a large set of results to use statistical methods is clear. |
Gomez-Jeria, J S; Clavijo, E; Carcamo, J J; Gutierrez, S An Infrared and Sem Study of the Margins of Some German Hyperinflation Postage Stamps Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (2), pp. 870-892, 2018, ISSN: 0975-8585. Resumen | Enlaces | BibTeX | Etiquetas: archeology, archeophilately, cellulose, database, electron ft-ir germany, hyperinflation, infrared inks kaolinite, microscopy, oxides, pigments, postage raman scanning sem, spectra, spectral spectroscopy, stamps, white zinc @article{RN411, title = {An Infrared and Sem Study of the Margins of Some German Hyperinflation Postage Stamps}, author = { J.S. Gomez-Jeria and E. Clavijo and J.J. Carcamo and S. Gutierrez}, url = {/brokenurl#<Go to ISI>://WOS:000432267600105}, issn = {0975-8585}, year = {2018}, date = {2018-01-01}, journal = {Research Journal of Pharmaceutical Biological and Chemical Sciences}, volume = {9}, number = {2}, pages = {870-892}, abstract = {Infrared spectroscopy and scanning electron microscopy (SEM) studies were performed on the margins (the area without printed colors) of a set of German postage stamps dated 1923 and corresponding to the hyperinflationary period of economy. SEM results showed the presence of Al, Si, Zn and S in the samples, but in different combinations. Sulfur is considered to be a contaminant. The Al-Si combination is credited to kaolinite, Zn to ZnO and unaccompanied Al possibly to Al2O3. Several experimental IR bands of kaolinite agree with the suggestion of its existence in some stamps. In the case of Al and Zn alone we have supposed that, with the passing of time and with the help of moisture, AlOH and ZnOH were formed in a quantity allowing detecting some of the metal- OH bands by IR spectroscopy. On the basis of previous infrared experimental results on Al and Zn hydroxides we assigned some IR bands to the OH groups bonded to these metals. Our results indicate that it is highly probable that the paper used to print these postage stamps was originated in more than one paper mill.}, keywords = {archeology, archeophilately, cellulose, database, electron ft-ir germany, hyperinflation, infrared inks kaolinite, microscopy, oxides, pigments, postage raman scanning sem, spectra, spectral spectroscopy, stamps, white zinc}, pubstate = {published}, tppubtype = {article} } Infrared spectroscopy and scanning electron microscopy (SEM) studies were performed on the margins (the area without printed colors) of a set of German postage stamps dated 1923 and corresponding to the hyperinflationary period of economy. SEM results showed the presence of Al, Si, Zn and S in the samples, but in different combinations. Sulfur is considered to be a contaminant. The Al-Si combination is credited to kaolinite, Zn to ZnO and unaccompanied Al possibly to Al2O3. Several experimental IR bands of kaolinite agree with the suggestion of its existence in some stamps. In the case of Al and Zn alone we have supposed that, with the passing of time and with the help of moisture, AlOH and ZnOH were formed in a quantity allowing detecting some of the metal- OH bands by IR spectroscopy. On the basis of previous infrared experimental results on Al and Zn hydroxides we assigned some IR bands to the OH groups bonded to these metals. Our results indicate that it is highly probable that the paper used to print these postage stamps was originated in more than one paper mill. |
Meneses-Franco, A; Campos-Vallette, M; Vasquez, S O; Soto-Bustamante, E A Er-Doped Nanostructured Batio3 for Nir to Visible Upconversion Artículo de revista Materials, 11 (10), 2018, ISSN: 1996-1944. Resumen | Enlaces | BibTeX | Etiquetas: barium crystal, dielectric-properties, erbium, fabrication, ions microstructure, nanoparticle, nanoparticles, nanotechnology, particles, photoluminescent, spectra, technology, titanate, upconversion @article{RN409, title = {Er-Doped Nanostructured Batio3 for Nir to Visible Upconversion}, author = { A. Meneses-Franco and M. Campos-Vallette and S.O. Vasquez and E.A. Soto-Bustamante}, url = {/brokenurl#<Go to ISI>://WOS:000448658400164}, doi = {10.3390/ma11101950}, issn = {1996-1944}, year = {2018}, date = {2018-01-01}, journal = {Materials}, volume = {11}, number = {10}, abstract = {Photoluminescent mechanisms in erbium-doped barium titanate nanoparticle systems were studied. Er3+ ions were introduced into the BaTiO3 lattice by the sol-gel method. The resulting Er3+ concentration was between 0% and 5%, with Ba/Ti ratios of 1.008 and 0.993. The stoichiometry of Ba and Ti concentrations in the lattice influenced the doping mechanism and placement of erbium ions in the lattice structure. Our research shows the existence of a strong correlation between Ba/Ti ratios, erbium concentration, phase structure and doping site location on the upconversion photoluminescence mechanisms. Competing upconversion emissions H-2(11/2)/(S3/2I15/2)-S-4-I-4 at 523 and 548 nm respectively and other photoluminescent mechanisms as (I9/2I11/2)-I-4-I-4 around 4000 nm (2500 cm(-1)) were studied using Raman and emission spectroscopy. The upconversion process is predominant over other photoluminescent decay when the material presents high distortion in the surrounding activator.}, keywords = {barium crystal, dielectric-properties, erbium, fabrication, ions microstructure, nanoparticle, nanoparticles, nanotechnology, particles, photoluminescent, spectra, technology, titanate, upconversion}, pubstate = {published}, tppubtype = {article} } Photoluminescent mechanisms in erbium-doped barium titanate nanoparticle systems were studied. Er3+ ions were introduced into the BaTiO3 lattice by the sol-gel method. The resulting Er3+ concentration was between 0% and 5%, with Ba/Ti ratios of 1.008 and 0.993. The stoichiometry of Ba and Ti concentrations in the lattice influenced the doping mechanism and placement of erbium ions in the lattice structure. Our research shows the existence of a strong correlation between Ba/Ti ratios, erbium concentration, phase structure and doping site location on the upconversion photoluminescence mechanisms. Competing upconversion emissions H-2(11/2)/(S3/2I15/2)-S-4-I-4 at 523 and 548 nm respectively and other photoluminescent mechanisms as (I9/2I11/2)-I-4-I-4 around 4000 nm (2500 cm(-1)) were studied using Raman and emission spectroscopy. The upconversion process is predominant over other photoluminescent decay when the material presents high distortion in the surrounding activator. |
Gomez-Jeria, J S; Clavijo, E; Gutierrez, S A Qualitative Infrared and Scanning Electron Microscopy Study of the Margins of Fourteen World Postage Stamps Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (6), pp. 1719-+, 2018, ISSN: 0975-8585. Resumen | Enlaces | BibTeX | Etiquetas: archeology, cellulose, electron ft-ir infrared kaolinite, microscopy, paper philately, pigments, postage raman scanning sem, spectra, spectroscopy, stamps, xrf @article{RN415, title = {A Qualitative Infrared and Scanning Electron Microscopy Study of the Margins of Fourteen World Postage Stamps}, author = { J.S. Gomez-Jeria and E. Clavijo and S. Gutierrez}, url = {/brokenurl#<Go to ISI>://WOS:000449630700274}, issn = {0975-8585}, year = {2018}, date = {2018-01-01}, journal = {Research Journal of Pharmaceutical Biological and Chemical Sciences}, volume = {9}, number = {6}, pages = {1719-+}, abstract = {Fourteen heavily damaged postage stamps were chosen for an infrared and scanning electron microscopy (SEM) characterization of their non-printed margins. The results show the presence of kaolinite used as filler in all but two samples. These last two contain aluminum (with an Al-OH moiety). One stamp seems to contain barium in the form of sulfate. One stamp contains lead in an unknown chemical compound. All these results were incorporated into a database for future analysis. Quantum chemical calculations of diverse large models of cellulose seem absolutely necessary for the IR band assignments.}, keywords = {archeology, cellulose, electron ft-ir infrared kaolinite, microscopy, paper philately, pigments, postage raman scanning sem, spectra, spectroscopy, stamps, xrf}, pubstate = {published}, tppubtype = {article} } Fourteen heavily damaged postage stamps were chosen for an infrared and scanning electron microscopy (SEM) characterization of their non-printed margins. The results show the presence of kaolinite used as filler in all but two samples. These last two contain aluminum (with an Al-OH moiety). One stamp seems to contain barium in the form of sulfate. One stamp contains lead in an unknown chemical compound. All these results were incorporated into a database for future analysis. Quantum chemical calculations of diverse large models of cellulose seem absolutely necessary for the IR band assignments. |
2015 |
Campos-Vallette, M; Aguayo, T Vibrational Spectroscopy for the Study of Chilean Cultural Heritage Artículo de revista Heritage Science, 3 , 2015, ISSN: 2050-7445. Resumen | Enlaces | BibTeX | Etiquetas: art, enhanced ft-raman, identification, iron-oxides, micro-raman, microspectroscopy paintings, pigments, raman-scattering, spectra @article{RN263, title = {Vibrational Spectroscopy for the Study of Chilean Cultural Heritage}, author = { M. Campos-Vallette and T. Aguayo}, url = {/brokenurl#<Go to ISI>://WOS:000356922100001}, doi = {10.1186/s40494-015-0047-0}, issn = {2050-7445}, year = {2015}, date = {2015-01-01}, journal = {Heritage Science}, volume = {3}, abstract = {Background: Natural and synthetic colouring products along with its associated supporting materials have been studied in several expressions of the Chilean cultural heritage using vibrational spectroscopy. These expressions include archaeological remains as well as works of art., Results: Among the materials studied so far we can count pigments found in archaeological sites from the north of Chile, in plaster (wall paintings) and in polychrome (beams), and dyes mainly related to added components on historic silk textiles. Identification of materials resulted to be relevant to know about Chilean culture through history., Conclusions: The vibrational knowledge obtained contributes to give solid data as a complement to the different information aspects collected by conservation professionals involved in the characterization and conservation procedures of cultural heritage and also it gives us the opportunity to share knowledge and to give value to objects that not always are of the public domain.}, keywords = {art, enhanced ft-raman, identification, iron-oxides, micro-raman, microspectroscopy paintings, pigments, raman-scattering, spectra}, pubstate = {published}, tppubtype = {article} } Background: Natural and synthetic colouring products along with its associated supporting materials have been studied in several expressions of the Chilean cultural heritage using vibrational spectroscopy. These expressions include archaeological remains as well as works of art., Results: Among the materials studied so far we can count pigments found in archaeological sites from the north of Chile, in plaster (wall paintings) and in polychrome (beams), and dyes mainly related to added components on historic silk textiles. Identification of materials resulted to be relevant to know about Chilean culture through history., Conclusions: The vibrational knowledge obtained contributes to give solid data as a complement to the different information aspects collected by conservation professionals involved in the characterization and conservation procedures of cultural heritage and also it gives us the opportunity to share knowledge and to give value to objects that not always are of the public domain. |
2014 |
Ogalde, J P; Salas, C O; Lara, N; Leyton, P; Paipa, C; Campos-Vallette, M; Arriaza, B Multi-Instrumental Identification of Orpiment in Archaeological Mortuary Contexts Artículo de revista Journal of the Chilean Chemical Society, 59 (3), pp. 2571-2573, 2014, ISSN: 0717-9707. Resumen | Enlaces | BibTeX | Etiquetas: ceramics, chile, chorrillos, color, glass manuscripts, northern pararealgar, persian pigments, raman raman, realgar, sem-edx, spectra, spectroscopy @article{RN210, title = {Multi-Instrumental Identification of Orpiment in Archaeological Mortuary Contexts}, author = { J.P. Ogalde and C.O. Salas and N. Lara and P. Leyton and C. Paipa and M. Campos-Vallette and B. Arriaza}, url = {/brokenurl#<Go to ISI>://WOS:000347833800010}, doi = {10.4067/S0717-97072014000300010}, issn = {0717-9707}, year = {2014}, date = {2014-01-01}, journal = {Journal of the Chilean Chemical Society}, volume = {59}, number = {3}, pages = {2571-2573}, abstract = {This paper reports on an unknown yellowish mineral compound found in an archaeological context from Chorrillos cemetery (Calama, Chile) dating to the Early Formative period (800 - 200 B.C.). We used optic microscopy, SEM, EDX, H-1-RMN, C-13-RMN, and infrared (IR) and Raman spectroscopy to tease out the chemical and molecular composition of the sample. The microscopic images show amorphous yellowish granulates with heterogeneous chemical surfaces. H-1-RMN and C-13-RMN negative results show that the sample is free of organic matter. The SEM and EDX indicate the presence of arsenic and sulfur in the sample. The IR and Raman analyses suggest the presence of orpiment which is a toxic yellow arsenic sulfide mineral.}, keywords = {ceramics, chile, chorrillos, color, glass manuscripts, northern pararealgar, persian pigments, raman raman, realgar, sem-edx, spectra, spectroscopy}, pubstate = {published}, tppubtype = {article} } This paper reports on an unknown yellowish mineral compound found in an archaeological context from Chorrillos cemetery (Calama, Chile) dating to the Early Formative period (800 - 200 B.C.). We used optic microscopy, SEM, EDX, H-1-RMN, C-13-RMN, and infrared (IR) and Raman spectroscopy to tease out the chemical and molecular composition of the sample. The microscopic images show amorphous yellowish granulates with heterogeneous chemical surfaces. H-1-RMN and C-13-RMN negative results show that the sample is free of organic matter. The SEM and EDX indicate the presence of arsenic and sulfur in the sample. The IR and Raman analyses suggest the presence of orpiment which is a toxic yellow arsenic sulfide mineral. |
Galdámez, A; Lopez-Vergara, F; Cid, N V; Manriquez, V; Avila, R E Copper Substitutions in Synthetic Miargyrite Alpha-Agsbs2 Mineral: Synthesis, Characterization and Dielectrical Properties Artículo de revista Materials Chemistry and Physics, 143 (3), pp. 1372-1377, 2014, ISSN: 0254-0584. Resumen | Enlaces | BibTeX | Etiquetas: agsbs2, chalcogenides, chemical conductivity, dielectric diffraction, direct-band-gap, electrical optical-properties, powder properties, spectra, synthesis, tl @article{RN204, title = {Copper Substitutions in Synthetic Miargyrite Alpha-Agsbs2 Mineral: Synthesis, Characterization and Dielectrical Properties}, author = {A. Gald\'{a}mez and F. Lopez-Vergara and N.V. Cid and V. Manriquez and R.E. Avila}, url = {/brokenurl#<Go to ISI>://WOS:000331347500066}, doi = {10.1016/j.matchemphys.2013.11.048}, issn = {0254-0584}, year = {2014}, date = {2014-01-01}, journal = {Materials Chemistry and Physics}, volume = {143}, number = {3}, pages = {1372-1377}, publisher = {2013 Elsevier B.V.}, abstract = {The nominal compositions Ag0.8Cu0.2SbS2 and Ag0.7Cu0.3SbS2 have been synthesized by conventional ceramic solid-state reaction at high temperature. X-ray diffraction (XRD) and scanning electron microscopy chemical analysis (SEM-EDAX) revealed single phases, isostructural to the natural miargyrite alpha-AgSbS2 mineral. Examination of the lattice parameters shows a decrease in the cell volume with increasing copper substitutions. The Raman analysis displays absorptions which may be assigned to the Sb-S stretching vibrations of the SbS3 pyramids. The impedance-frequency analysis showed grain boundary and electrode interface contributions in non-Debye type relaxation, following Jonscher's universal power law. The giant permittivity response is attributed to extrinsic effects without evidence of a ferroelectric transition. Summerfield scaling, leading to the superposition of impedance analysis, implies that the relaxation is thermally activated, without introducing more than one underlying transport mechanism.}, keywords = {agsbs2, chalcogenides, chemical conductivity, dielectric diffraction, direct-band-gap, electrical optical-properties, powder properties, spectra, synthesis, tl}, pubstate = {published}, tppubtype = {article} } The nominal compositions Ag0.8Cu0.2SbS2 and Ag0.7Cu0.3SbS2 have been synthesized by conventional ceramic solid-state reaction at high temperature. X-ray diffraction (XRD) and scanning electron microscopy chemical analysis (SEM-EDAX) revealed single phases, isostructural to the natural miargyrite alpha-AgSbS2 mineral. Examination of the lattice parameters shows a decrease in the cell volume with increasing copper substitutions. The Raman analysis displays absorptions which may be assigned to the Sb-S stretching vibrations of the SbS3 pyramids. The impedance-frequency analysis showed grain boundary and electrode interface contributions in non-Debye type relaxation, following Jonscher's universal power law. The giant permittivity response is attributed to extrinsic effects without evidence of a ferroelectric transition. Summerfield scaling, leading to the superposition of impedance analysis, implies that the relaxation is thermally activated, without introducing more than one underlying transport mechanism. |
2013 |
Garrido, C; Aguayo, T; Clavijo, E; Gomez-Jeria, J S; Campos-Vallette, M The Effect of the Ph on the Interaction of L-Arginine with Colloidal Silver Nanoparticles. A Raman and Sers Study Artículo de revista Journal of Raman Spectroscopy, 44 (8), pp. 1105-1110, 2013, ISSN: 0377-0486. Resumen | Enlaces | BibTeX | Etiquetas: amino-acids, aromatic-hydrocarbons, enhanced extended huckel hydrochloride l-arginine, l-lysine, polycyclic potential protein, raman scattering scattering, spectra, spectroscopy, surface surface, temperature, theory zeta @article{RN154, title = {The Effect of the Ph on the Interaction of L-Arginine with Colloidal Silver Nanoparticles. A Raman and Sers Study}, author = { C. Garrido and T. Aguayo and E. Clavijo and J.S. Gomez-Jeria and M. Campos-Vallette}, url = {/brokenurl#<Go to ISI>://WOS:000323180700006}, doi = {10.1002/jrs.4331}, issn = {0377-0486}, year = {2013}, date = {2013-01-01}, journal = {Journal of Raman Spectroscopy}, volume = {44}, number = {8}, pages = {1105-1110}, publisher = {2013 John Wiley & Sons, Ltd.}, abstract = {Raman and surface enhanced Raman scattering (SERS) spectroscopies were used to study the pH effect (7 to 9) on the interaction of arginine (Arg) with colloidal Ag nanoparticles (AgNps). A new methodology was implemented in order to obtain reproducible SERS spectra in solution. The dependence of the Arg concentration on the stability of the AgNps is discussed. A pH increasing of the colloidal solution to the limits of the Arg pKa(2) value induces a preferential and stable Arg-metal interaction. potential measurements of the Arg-AgNps system at different pH conditions studied provide information about the Arg-AgNps interaction; the pH increasing favors the interaction. SERS spectra at pH 7 indicate that the molecule interacts with the Ag surface only through the guanidinium fragment. By increasing the pH to 9, the molecule adopts a new conformation on the surface; the metal-analyte interaction is verified through the guanidinium, carboxylate and the aliphatic moieties. In addition, theoretical calculations performed by using the extended Huckel method for a model of Arg interacting with an Ag surface support the observed SERS results.}, keywords = {amino-acids, aromatic-hydrocarbons, enhanced extended huckel hydrochloride l-arginine, l-lysine, polycyclic potential protein, raman scattering scattering, spectra, spectroscopy, surface surface, temperature, theory zeta}, pubstate = {published}, tppubtype = {article} } Raman and surface enhanced Raman scattering (SERS) spectroscopies were used to study the pH effect (7 to 9) on the interaction of arginine (Arg) with colloidal Ag nanoparticles (AgNps). A new methodology was implemented in order to obtain reproducible SERS spectra in solution. The dependence of the Arg concentration on the stability of the AgNps is discussed. A pH increasing of the colloidal solution to the limits of the Arg pKa(2) value induces a preferential and stable Arg-metal interaction. potential measurements of the Arg-AgNps system at different pH conditions studied provide information about the Arg-AgNps interaction; the pH increasing favors the interaction. SERS spectra at pH 7 indicate that the molecule interacts with the Ag surface only through the guanidinium fragment. By increasing the pH to 9, the molecule adopts a new conformation on the surface; the metal-analyte interaction is verified through the guanidinium, carboxylate and the aliphatic moieties. In addition, theoretical calculations performed by using the extended Huckel method for a model of Arg interacting with an Ag surface support the observed SERS results. |
2012 |
Leyton, P; Saladino, R; Crestini, C; Campos-Vallette, M; Paipa, C; Berrios, A; Fuentes, S; Zarate, R A Influence of Tio2 on Prebiotic Thermal Synthesis of the Gly-Gln Polymer Artículo de revista Amino Acids, 42 (6), pp. 2079-2088, 2012, ISSN: 0939-4451. Resumen | Enlaces | BibTeX | Etiquetas: amino-acids, chemistry, condensation conditions, crystalline diketopiperazine, dioxide, dynamics, earth formation ft-ir glutamic glycine, peptide prebiotic primitive reaction, self-disproportionation, spectra, spectroscopy, synthesis, thermal titanium vibrational @article{RN29d, title = {Influence of Tio2 on Prebiotic Thermal Synthesis of the Gly-Gln Polymer}, author = { P. Leyton and R. Saladino and C. Crestini and M. Campos-Vallette and C. Paipa and A. Berrios and S. Fuentes and R.A. Zarate}, url = {/brokenurl#<Go to ISI>://WOS:000304150300004}, doi = {10.1007/s00726-011-0939-6}, issn = {0939-4451}, year = {2012}, date = {2012-01-01}, journal = {Amino Acids}, volume = {42}, number = {6}, pages = {2079-2088}, abstract = {The role of the titanium dioxide (rutile and anatase) with and without room light on the thermal synthesis of the glycine--glutamine (Gly-Gln) polymer is described. The efficiency in percentage of polymerization with room light was increased in 6% in the presence of rutile and in 23% in the presence of anatase. The thermal synthesis in the molten state was carried out in the absence and presence of both oxides. In all cases, the vibrational spectra showed characteristic group frequencies corresponding to a polypeptide structure. No spectral differences were observed by room light effect on the polymer on rutile. However, the polymer obtained in the presence of anatase and room light shows spectral changes associated with the formation of shorter new abundant and conformationally different species compared with the original polymer. The SEM-EDX characterization of the solid phase involved in the thermal synthesis showed that the morphology of the polypeptide is different in the presence of rutile compared to anatase. The SDS-PAGE and GPC results suggest that smaller chains are formed in the presence of both oxides and the distribution of the size and weight of each polymer molecule is completely different when the condensation is performed in the presence of anatase or rutile. Nuclear magnetic resonance analyses confirmed the incorporation of both Gly and Gln residues in the polymers, with a prevalence of Gly. Both possible sequences -GlyGln- and -GlnGly- were also detected.}, keywords = {amino-acids, chemistry, condensation conditions, crystalline diketopiperazine, dioxide, dynamics, earth formation ft-ir glutamic glycine, peptide prebiotic primitive reaction, self-disproportionation, spectra, spectroscopy, synthesis, thermal titanium vibrational}, pubstate = {published}, tppubtype = {article} } The role of the titanium dioxide (rutile and anatase) with and without room light on the thermal synthesis of the glycine--glutamine (Gly-Gln) polymer is described. The efficiency in percentage of polymerization with room light was increased in 6% in the presence of rutile and in 23% in the presence of anatase. The thermal synthesis in the molten state was carried out in the absence and presence of both oxides. In all cases, the vibrational spectra showed characteristic group frequencies corresponding to a polypeptide structure. No spectral differences were observed by room light effect on the polymer on rutile. However, the polymer obtained in the presence of anatase and room light shows spectral changes associated with the formation of shorter new abundant and conformationally different species compared with the original polymer. The SEM-EDX characterization of the solid phase involved in the thermal synthesis showed that the morphology of the polypeptide is different in the presence of rutile compared to anatase. The SDS-PAGE and GPC results suggest that smaller chains are formed in the presence of both oxides and the distribution of the size and weight of each polymer molecule is completely different when the condensation is performed in the presence of anatase or rutile. Nuclear magnetic resonance analyses confirmed the incorporation of both Gly and Gln residues in the polymers, with a prevalence of Gly. Both possible sequences -GlyGln- and -GlnGly- were also detected. |
2018 |
An Infrared, Sem and Xrf Study of the Paper of a 1588 Spanish Book Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (4), pp. 1581-1590, 2018, ISSN: 0975-8585. |
An Infrared and Sem Study of the Margins of Some Estonian Postage Stamps Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (3), pp. 1258-1279, 2018, ISSN: 0975-8585. |
An Infrared and Sem Study of the Margins of Some German Hyperinflation Postage Stamps Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (2), pp. 870-892, 2018, ISSN: 0975-8585. |
Er-Doped Nanostructured Batio3 for Nir to Visible Upconversion Artículo de revista Materials, 11 (10), 2018, ISSN: 1996-1944. |
A Qualitative Infrared and Scanning Electron Microscopy Study of the Margins of Fourteen World Postage Stamps Artículo de revista Research Journal of Pharmaceutical Biological and Chemical Sciences, 9 (6), pp. 1719-+, 2018, ISSN: 0975-8585. |
2015 |
Vibrational Spectroscopy for the Study of Chilean Cultural Heritage Artículo de revista Heritage Science, 3 , 2015, ISSN: 2050-7445. |
2014 |
Multi-Instrumental Identification of Orpiment in Archaeological Mortuary Contexts Artículo de revista Journal of the Chilean Chemical Society, 59 (3), pp. 2571-2573, 2014, ISSN: 0717-9707. |
Copper Substitutions in Synthetic Miargyrite Alpha-Agsbs2 Mineral: Synthesis, Characterization and Dielectrical Properties Artículo de revista Materials Chemistry and Physics, 143 (3), pp. 1372-1377, 2014, ISSN: 0254-0584. |
2013 |
The Effect of the Ph on the Interaction of L-Arginine with Colloidal Silver Nanoparticles. A Raman and Sers Study Artículo de revista Journal of Raman Spectroscopy, 44 (8), pp. 1105-1110, 2013, ISSN: 0377-0486. |
2012 |
Influence of Tio2 on Prebiotic Thermal Synthesis of the Gly-Gln Polymer Artículo de revista Amino Acids, 42 (6), pp. 2079-2088, 2012, ISSN: 0939-4451. |