RAFAEL ZAMORANO - Academia.edu (original) (raw)
Papers by RAFAEL ZAMORANO
Stream-wise variation of mean enthalpy flow rates, HRR = 58 kW. Right: Centerline mean temperatur... more Stream-wise variation of mean enthalpy flow rates, HRR = 58 kW. Right: Centerline mean temperature rise-black symbols represent simulation results and gray dotted line experimental correlation from McCaffrey (1979) experiments-. Source: Wang, Y. et al.
The advantages of digitisation technologies, such as 3D scanning, photogrammetry and 3D modelling... more The advantages of digitisation technologies, such as 3D scanning, photogrammetry and 3D modelling, for the documentation and dissemination of cultural heritage artefacts is well understood by researchers. Nevertheless, practitioners, in particular those in developing countries, still have a lack of understanding of how 3D technologies could work for them in order to support their collections. This paper presents ongoing efforts to engage with museums in Brazil, in particular the National History Museum in Rio de Janeiro, in order to raise awareness of the potential of 3D technologies. Rather than applying 3D digitisation technologies on artefacts where it is known that the techniques can provide an easy solution, our approach was more experiments. Hence, several ivory artefacts were selected, including various figurines and a carved Junk Boat from East Asia which are part of the museum collection and which present particular problems both in terms of conservation and dissemination. ...
Restauracion De Suelos En Mineria a Cielo Abierto Ordenacion De Zonas De Montana Tercer Curso De Ordenacion Del Territorio Vol 2 1984 Isbn 84 398 3238 9 Pags 301 318, 1984
The Faseb Journal, Apr 1, 2010
The Faseb Journal, Apr 1, 2010
Archivos del Instituto de Cardiología de México
The purpose of this study was to establish the molecular mechanism whereby captopril prevents the... more The purpose of this study was to establish the molecular mechanism whereby captopril prevents the formation of active oxygen species, since many studies have provided evidence that postischemic myocardial dysfunction is mediated, at least in part, by the generation of these agents. Results indicate that captopril is a potent inhibitor of certain reactions mediated by O2-. However, this interference of captopril was not understood as an scavenging activity against the free radicals generated. The data could be explained by considering a direct interaction of captopril with the metal ions present that catalyse the formation of O2-. This mechanism could be of biological relevance.
Journal of the Chemical Society, Dalton Transactions, 1998
Page 1. DALTONFULL PAPER J. Chem. Soc., Dalton Trans., 1998, Pages 667674 667 Pinch-porphyrins, ... more Page 1. DALTONFULL PAPER J. Chem. Soc., Dalton Trans., 1998, Pages 667674 667 Pinch-porphyrins, new spectroscopic and kinetic models of peroxidases Yasmi Reyes-Ortega,*,a,b Cecilio Alvarez-Toledano,b Daniel ...
Journal of Non-Crystalline Solids, 2007
We present measurements of low-field power absorption (LFA) at 9.45 GHz on an amorphous ribbon of... more We present measurements of low-field power absorption (LFA) at 9.45 GHz on an amorphous ribbon of nominal composition (Fe 0.06 Co 0.94) 75 Si 15 B 10 , at room temperature. These results show an anti-symmetrical shape around zero magnetic field that peaks at ±34 Oe. We also present measurements of magnetoimpedance (MI) at 60 MHz and 3 GHz. In order to make a proper comparison between these experiments, the real part of magnetoimpedance, Re(Z s), was numerically derived to obtain dRe(Z s)/dH; leading also to an anti-symmetrical plot that peaks at the same fields that LFA. By using the complex Poynting vector, we show that LFA and MI are very similar processes and conclude that both measurements are a manifestation of the same response to electromagnetic absorption, in which the same physical processes take place.
Journal of Molecular Structure, 2002
... Infrared spectra of KBr pellets of the complex were recorded on a PerkinElmer 283B or 1420 s... more ... Infrared spectra of KBr pellets of the complex were recorded on a PerkinElmer 283B or 1420 spectrophotometers in the range 4000200 cm −1 . Electronic spectra were recorded in a Shimadzu UV/VIS/NIR 3100 spectrophotometer on 0.1 mmol methanolic sample solution at ...
Journal of Molecular Structure, 2003
... Contact Information , E-mail The Corresponding Author , Daniel Ramı́rez-Rosales c , Sylvain B... more ... Contact Information , E-mail The Corresponding Author , Daniel Ramı́rez-Rosales c , Sylvain Bernès a , José Guadalupe Ramı́rez Bokhimi d , Rafael Zamorano-Ulloa c ... b=8.9768(5), β=111.916(5)°, and Z=4. The electronic spectrum of 1 shows a broad band with λ max 841 nm ( ...
![Research paper thumbnail of Weak ferromagnetic behavior, crystal structure, and electronic studies of novel [Cu(II)(Br)(PhCO2)(Sp)] (Sp=(−)-sparteine) complex](https://attachments.academia-assets.com/110696815/thumbnails/1.jpg)
](Journal of Molecular Structure, 2006
Complex [Cu(II)(Br)(PhCO 2)(Sp)] 1 is obtained starting from copper(0), (K)-sparteine (sp) and be... more Complex [Cu(II)(Br)(PhCO 2)(Sp)] 1 is obtained starting from copper(0), (K)-sparteine (sp) and benzoyl bromide. 1 Crystallizes in the monoclinic space group P2 1 with aZ14.8857(11), bZ8.9257(9), cZ17.4456(14) Å , bZ111.689(5)8, and ZZ4. The UV-vis spectrum is characteristic of Cu(II) complexes with tetragonally distorted square pyramidal geometry. The far IR spectrum of 1 shows characteristic vibrations of Cu-Br (239 cm K1), Cu-N (437 cm K1) and Cu-O (466 cm K1) bonds. The 1 H NMR broad chemical shifts of 1 integrated for a total of 31 protons and are typical of Cu(II) complexes. ESR spectra of polycrystalline 1 at 77 and 300 K show axial spectra with areas in the ratio A 77 /A 300 Z 4.02, suggesting a very weak Cu-Cu ferromagnetic interaction. Complex 1-doped with Zn(II) gives hfs with hyperfine interaction constant value A s Z112.45!10 K4 cm K1. The magnetization vs temperature data in the 2-299 K range, show that cupric ion pairs interact through a small antiferromagnetic Heisenberg exchange energy-JS 1 $S 2 with a ground singlet state SZ0, separated by JZK1.3 cm K1 from the excited triplet state SZ1. The sign of the very weak interchange interaction constant, J, does not agree with the ESR spectra areas ratio of 1 at 77 and 300 K, which is a more accurate quantification of the weak ferromagnetic interaction Cu-Cu through the space.
Journal of Magnetism and Magnetic Materials, 2010
Magnetosensitive microwave absorption measurements of polycrystalline ferrite Ni 0.35 Zn 0.65 Fe ... more Magnetosensitive microwave absorption measurements of polycrystalline ferrite Ni 0.35 Zn 0.65 Fe 2 O 4 was carried out at 9.4 GHz (X-band) as a function of temperature. Temperature dependence of the total linewidth (DH pp) deduced from the resonance spectra showed the passage through the Curie point (T c $ 430 K). Additionally, the plot DH pp vs. T also indicated the existence of another magnetic phase transition at $ 240 K, which can be associated with a Yafet-Kittel-type canting of the magnetic moments. Low-field microwave absorption (LFMA) and the magnetically modulated microwave absorption spectroscopy (MAMMAS) were used to give a further knowledge on this material. For low temperature, these techniques give evidence of a Yafet-Kittel-type canting of the magnetic moments.
Journal of Magnetism and Magnetic Materials, 2008
... through a normal direction to the ribbon plane. 3. Results and discussion. Fig. 1 shows the r... more ... through a normal direction to the ribbon plane. 3. Results and discussion. Fig. 1 shows the resonant microwave absorption spectra [dP/dH f(H dc )] of NiZn ferrite at a few selected temperatures. A single broad line is observed in ...
Journal of Magnetism and Magnetic Materials, 2007
We have investigated the Verwey phase transition (VPT) by two novel non-resonant microwave absorp... more We have investigated the Verwey phase transition (VPT) by two novel non-resonant microwave absorption techniques: low-field absorption (LFA) and magnetically modulated microwave absorption spectroscopy (MAMMAS). Measurements were carried out on sintered polycrystalline samples of Fe 3 O 4 , in the 77-300 K temperature range. LFA refers to the microwave absorption around the zero DC field range (À1000oH DC o+1000 G). LFA measurements showed an hysteretic behavior; a minimum in the hysteresis loop width was observed at 126 K, which can be associated with a minimum in magnetic anisotropy, as a consequence of charge localization below the VPT. MAMMAS experiments are based on the variations in microwave absorption (at constant H DC), as a function of temperature, and seem particularly well adapted to detect a wide range of phase transitions. In the magnetite case, a continuous increase in the microwave power absorption level was observed as temperature decreased, reaching a strong maximum at 130 K and a minimum at 100 K. An inflection point at 126 K was found, in very good agreement with LFA measurements. These results are discussed in detail.
Journal of Bioenergetics and Biomembranes, 1991
Cadmium ions inhibit membrane-bound succinate dehydrogenase with a second-order rate constant of ... more Cadmium ions inhibit membrane-bound succinate dehydrogenase with a second-order rate constant of 10.42 mM-~ s t at pH 7.35 and 25°C. Succinate and malonate protect the enzyme against cadmium ion inhibition. The protection pattern exerted by succinate and malonate suggests that the group modified by cadmium is located at the active site. The pH curve of inactivation by Cd 2+ indicates the involvement of an amino acid residue with pKa of 7.23.
Stream-wise variation of mean enthalpy flow rates, HRR = 58 kW. Right: Centerline mean temperatur... more Stream-wise variation of mean enthalpy flow rates, HRR = 58 kW. Right: Centerline mean temperature rise-black symbols represent simulation results and gray dotted line experimental correlation from McCaffrey (1979) experiments-. Source: Wang, Y. et al.
The advantages of digitisation technologies, such as 3D scanning, photogrammetry and 3D modelling... more The advantages of digitisation technologies, such as 3D scanning, photogrammetry and 3D modelling, for the documentation and dissemination of cultural heritage artefacts is well understood by researchers. Nevertheless, practitioners, in particular those in developing countries, still have a lack of understanding of how 3D technologies could work for them in order to support their collections. This paper presents ongoing efforts to engage with museums in Brazil, in particular the National History Museum in Rio de Janeiro, in order to raise awareness of the potential of 3D technologies. Rather than applying 3D digitisation technologies on artefacts where it is known that the techniques can provide an easy solution, our approach was more experiments. Hence, several ivory artefacts were selected, including various figurines and a carved Junk Boat from East Asia which are part of the museum collection and which present particular problems both in terms of conservation and dissemination. ...
Restauracion De Suelos En Mineria a Cielo Abierto Ordenacion De Zonas De Montana Tercer Curso De Ordenacion Del Territorio Vol 2 1984 Isbn 84 398 3238 9 Pags 301 318, 1984
The Faseb Journal, Apr 1, 2010
The Faseb Journal, Apr 1, 2010
Archivos del Instituto de Cardiología de México
The purpose of this study was to establish the molecular mechanism whereby captopril prevents the... more The purpose of this study was to establish the molecular mechanism whereby captopril prevents the formation of active oxygen species, since many studies have provided evidence that postischemic myocardial dysfunction is mediated, at least in part, by the generation of these agents. Results indicate that captopril is a potent inhibitor of certain reactions mediated by O2-. However, this interference of captopril was not understood as an scavenging activity against the free radicals generated. The data could be explained by considering a direct interaction of captopril with the metal ions present that catalyse the formation of O2-. This mechanism could be of biological relevance.
Journal of the Chemical Society, Dalton Transactions, 1998
Page 1. DALTONFULL PAPER J. Chem. Soc., Dalton Trans., 1998, Pages 667674 667 Pinch-porphyrins, ... more Page 1. DALTONFULL PAPER J. Chem. Soc., Dalton Trans., 1998, Pages 667674 667 Pinch-porphyrins, new spectroscopic and kinetic models of peroxidases Yasmi Reyes-Ortega,*,a,b Cecilio Alvarez-Toledano,b Daniel ...
Journal of Non-Crystalline Solids, 2007
We present measurements of low-field power absorption (LFA) at 9.45 GHz on an amorphous ribbon of... more We present measurements of low-field power absorption (LFA) at 9.45 GHz on an amorphous ribbon of nominal composition (Fe 0.06 Co 0.94) 75 Si 15 B 10 , at room temperature. These results show an anti-symmetrical shape around zero magnetic field that peaks at ±34 Oe. We also present measurements of magnetoimpedance (MI) at 60 MHz and 3 GHz. In order to make a proper comparison between these experiments, the real part of magnetoimpedance, Re(Z s), was numerically derived to obtain dRe(Z s)/dH; leading also to an anti-symmetrical plot that peaks at the same fields that LFA. By using the complex Poynting vector, we show that LFA and MI are very similar processes and conclude that both measurements are a manifestation of the same response to electromagnetic absorption, in which the same physical processes take place.
Journal of Molecular Structure, 2002
... Infrared spectra of KBr pellets of the complex were recorded on a PerkinElmer 283B or 1420 s... more ... Infrared spectra of KBr pellets of the complex were recorded on a PerkinElmer 283B or 1420 spectrophotometers in the range 4000200 cm −1 . Electronic spectra were recorded in a Shimadzu UV/VIS/NIR 3100 spectrophotometer on 0.1 mmol methanolic sample solution at ...
Journal of Molecular Structure, 2003
... Contact Information , E-mail The Corresponding Author , Daniel Ramı́rez-Rosales c , Sylvain B... more ... Contact Information , E-mail The Corresponding Author , Daniel Ramı́rez-Rosales c , Sylvain Bernès a , José Guadalupe Ramı́rez Bokhimi d , Rafael Zamorano-Ulloa c ... b=8.9768(5), β=111.916(5)°, and Z=4. The electronic spectrum of 1 shows a broad band with λ max 841 nm ( ...
Journal of Molecular Structure, 2006
Complex [Cu(II)(Br)(PhCO 2)(Sp)] 1 is obtained starting from copper(0), (K)-sparteine (sp) and be... more Complex [Cu(II)(Br)(PhCO 2)(Sp)] 1 is obtained starting from copper(0), (K)-sparteine (sp) and benzoyl bromide. 1 Crystallizes in the monoclinic space group P2 1 with aZ14.8857(11), bZ8.9257(9), cZ17.4456(14) Å , bZ111.689(5)8, and ZZ4. The UV-vis spectrum is characteristic of Cu(II) complexes with tetragonally distorted square pyramidal geometry. The far IR spectrum of 1 shows characteristic vibrations of Cu-Br (239 cm K1), Cu-N (437 cm K1) and Cu-O (466 cm K1) bonds. The 1 H NMR broad chemical shifts of 1 integrated for a total of 31 protons and are typical of Cu(II) complexes. ESR spectra of polycrystalline 1 at 77 and 300 K show axial spectra with areas in the ratio A 77 /A 300 Z 4.02, suggesting a very weak Cu-Cu ferromagnetic interaction. Complex 1-doped with Zn(II) gives hfs with hyperfine interaction constant value A s Z112.45!10 K4 cm K1. The magnetization vs temperature data in the 2-299 K range, show that cupric ion pairs interact through a small antiferromagnetic Heisenberg exchange energy-JS 1 $S 2 with a ground singlet state SZ0, separated by JZK1.3 cm K1 from the excited triplet state SZ1. The sign of the very weak interchange interaction constant, J, does not agree with the ESR spectra areas ratio of 1 at 77 and 300 K, which is a more accurate quantification of the weak ferromagnetic interaction Cu-Cu through the space.
Journal of Magnetism and Magnetic Materials, 2010
Magnetosensitive microwave absorption measurements of polycrystalline ferrite Ni 0.35 Zn 0.65 Fe ... more Magnetosensitive microwave absorption measurements of polycrystalline ferrite Ni 0.35 Zn 0.65 Fe 2 O 4 was carried out at 9.4 GHz (X-band) as a function of temperature. Temperature dependence of the total linewidth (DH pp) deduced from the resonance spectra showed the passage through the Curie point (T c $ 430 K). Additionally, the plot DH pp vs. T also indicated the existence of another magnetic phase transition at $ 240 K, which can be associated with a Yafet-Kittel-type canting of the magnetic moments. Low-field microwave absorption (LFMA) and the magnetically modulated microwave absorption spectroscopy (MAMMAS) were used to give a further knowledge on this material. For low temperature, these techniques give evidence of a Yafet-Kittel-type canting of the magnetic moments.
Journal of Magnetism and Magnetic Materials, 2008
... through a normal direction to the ribbon plane. 3. Results and discussion. Fig. 1 shows the r... more ... through a normal direction to the ribbon plane. 3. Results and discussion. Fig. 1 shows the resonant microwave absorption spectra [dP/dH f(H dc )] of NiZn ferrite at a few selected temperatures. A single broad line is observed in ...
Journal of Magnetism and Magnetic Materials, 2007
We have investigated the Verwey phase transition (VPT) by two novel non-resonant microwave absorp... more We have investigated the Verwey phase transition (VPT) by two novel non-resonant microwave absorption techniques: low-field absorption (LFA) and magnetically modulated microwave absorption spectroscopy (MAMMAS). Measurements were carried out on sintered polycrystalline samples of Fe 3 O 4 , in the 77-300 K temperature range. LFA refers to the microwave absorption around the zero DC field range (À1000oH DC o+1000 G). LFA measurements showed an hysteretic behavior; a minimum in the hysteresis loop width was observed at 126 K, which can be associated with a minimum in magnetic anisotropy, as a consequence of charge localization below the VPT. MAMMAS experiments are based on the variations in microwave absorption (at constant H DC), as a function of temperature, and seem particularly well adapted to detect a wide range of phase transitions. In the magnetite case, a continuous increase in the microwave power absorption level was observed as temperature decreased, reaching a strong maximum at 130 K and a minimum at 100 K. An inflection point at 126 K was found, in very good agreement with LFA measurements. These results are discussed in detail.
Journal of Bioenergetics and Biomembranes, 1991
Cadmium ions inhibit membrane-bound succinate dehydrogenase with a second-order rate constant of ... more Cadmium ions inhibit membrane-bound succinate dehydrogenase with a second-order rate constant of 10.42 mM-~ s t at pH 7.35 and 25°C. Succinate and malonate protect the enzyme against cadmium ion inhibition. The protection pattern exerted by succinate and malonate suggests that the group modified by cadmium is located at the active site. The pH curve of inactivation by Cd 2+ indicates the involvement of an amino acid residue with pKa of 7.23.