The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
R. Cesaroni - One of the best experts on this subject based on the ideXlab platform.
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on the chemical ladder of esters detection and formation of Ethyl Formate in the w51 e2 hot molecular core
Astronomy and Astrophysics, 2017Co-Authors: V. M. Rivilla, Maria T. Beltrán, Francesco Fontani, Paola Caselli, J Martinpintado, R. CesaroniAbstract:Context. In recent years, the detection of organic molecules with increasing complexity and potential biological relevance is opening the possibility to understand the formation of the building blocks of life in the interstellar medium. One of the families of molecules of substantial astrobiological interest are the esters. The simplest ester, mEthyl Formate (CH 3 OCHO), is rather abundant in star-forming regions. The next step in the chemical complexity of esters is Ethyl Formate, C 2 H 5 OCHO. Despite the increase in sensitivity of current telescopes, the detection of complex molecules with more than ten atoms such as C 2 H 5 OCHO is still a challenge. Only two detections of this species have been reported so far, which strongly limits our understanding of how complex molecules are formed in the interstellar medium. New detections towards additional sources with a wide range of physical conditions are crucial to differentiate between competing chemical models based on dust grain surface and gas-phase chemistry. Aims. We have searched for Ethyl Formate towards the W51 e2 hot molecular core, one of the most chemically rich sources in the Galaxy and one of the most promising regions to study prebiotic chemistry, especially after the recent discovery of the P−O bond, key in the formation of DNA. Methods. We have analyzed a spectral line survey towards the W51 e2 hot molecular core, which covers 44 GHz in the 1, 2 and 3 mm bands, carried out with the IRAM 30 m telescope. Results. We report the detection of the trans and gauche conformers of Ethyl Formate. A local thermodynamic equilibrium analysis indicates that the excitation temperature is 78 ± 10 K and that the two conformers have similar source-averaged column densities of (2.0 ± 0.3) × 10 -16 cm -2 and an abundance of ~10 -8 . We compare for the first time the observed molecular abundances of Ethyl Formate with different competing chemical models based on grain surface and gas-phase chemistry. Conclusions. We propose that grain-surface chemistry may have a dominant role in the formation of Ethyl Formate (and other complex organic molecules) in hot molecular cores, rather than reactions in the gas phase.
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On the chemical ladder of esters. Detection and formation of Ethyl Formate in the W51 e2 hot molecular core
Astronomy & Astrophysics, 2017Co-Authors: V. M. Rivilla, Maria T. Beltrán, Jesús Martín-pintado, Francesco Fontani, Paola Caselli, R. CesaroniAbstract:The detection of organic molecules with increasing complexity and potential biological relevance is opening the possibility to understand the formation of the building blocks of life in the interstellar medium. One of the families of molecules with astrobiological interest are the esters, whose simplest member, mEthyl Formate, is rather abundant in star-forming regions. The next step in the chemical complexity of esters is Ethyl Formate, C$_2$H$_5$OCHO. Only two detections of this species have been reported so far, which strongly limits our understanding of how complex molecules are formed in the interstellar medium. We have searched for Ethyl Formate towards the W51 e2 hot molecular core, one of the most chemically rich sources in the Galaxy and one of the most promising regions to study prebiotic chemistry, especially after the recent discovery of the P$-$O bond, key in the formation of DNA. We have analyzed a spectral line survey towards the W51 e2 hot molecular core, which covers 44 GHz in the 1, 2 and 3 mm bands, carried out with the IRAM 30m telescope. We report the detection of the trans and gauche conformers of Ethyl Formate. A Local Thermodynamic Equilibrium analysis indicates that the excitation temperature is 78$\pm$10 K and that the two conformers have similar source-averaged column densities of (2.0$\pm$0.3)$\times$10$^{16}$ cm$^{-2}$ and an abundance of $\sim$10$^{-8}$. We compare the observed molecular abundances of Ethyl Formate with different competing chemical models based on grain surface and gas-phase chemistry. We propose that grain-surface chemistry may have a dominant role in the formation of Ethyl Formate (and other complex organic molecules) in hot molecular cores, rather than reactions in the gas phase.
Phillip R Westmoreland - One of the best experts on this subject based on the ideXlab platform.
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isomer specific fuel destruction pathways in rich flames of mEthyl acetate and Ethyl Formate and consequences for the combustion chemistry of esters
Journal of Physical Chemistry A, 2007Co-Authors: Patrick Osswald, Ulf Struckmeier, Tina Kasper, Katharina Kohsehoinghaus, Juan Wang, Terrill A Cool, Nils Hansen, Phillip R WestmorelandAbstract:The influences of fuel-specific destruction pathways on flame chemistry are determined for two isomeric ester fuels, mEthyl acetate, CH3(CO)OCH3, and Ethyl Formate, H(CO)OC2H5, used as model representatives for biodiesel compounds, and their potential for forming air pollutants is addressed. Measurements are presented of major and intermediate species mole fractions in premixed, laminar flat flames using molecular-beam sampling and isomer-selective VUV-photoionization mass spectrometry. The observed intermediate species concentrations depend crucially on decomposition of the different radicals formed initially from the fuels. The mEthyl acetate structure leads to preferential formation of formaldehyde, while the Ethyl Formate isomer favors the production of acetaldehyde. Ethyl Formate also yields higher concentrations of the C2 species (C2H2 and C2H4) and C4 species (C4H2 and C4H4). Benzene concentrations, while larger for Ethyl Formate, are at least an order of magnitude smaller for both flames than seen...
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isomer specific fuel destruction pathways in rich flames of mEthyl acetate and Ethyl Formate and consequences for the combustion chemistry of esters
Journal of Physical Chemistry A, 2007Co-Authors: Patrick Osswald, Ulf Struckmeier, Tina Kasper, Katharina Kohsehoinghaus, Juan Wang, Terrill A Cool, Nils Hansen, Phillip R WestmorelandAbstract:The influences of fuel-specific destruction pathways on flame chemistry are determined for two isomeric ester fuels, mEthyl acetate, CH3(CO)OCH3, and Ethyl Formate, H(CO)OC2H5, used as model representatives for biodiesel compounds, and their potential for forming air pollutants is addressed. Measurements are presented of major and intermediate species mole fractions in premixed, laminar flat flames using molecular-beam sampling and isomer-selective VUV-photoionization mass spectrometry. The observed intermediate species concentrations depend crucially on decomposition of the different radicals formed initially from the fuels. The mEthyl acetate structure leads to preferential formation of formaldehyde, while the Ethyl Formate isomer favors the production of acetaldehyde. Ethyl Formate also yields higher concentrations of the C2 species (C2H2 and C2H4) and C4 species (C4H2 and C4H4). Benzene concentrations, while larger for Ethyl Formate, are at least an order of magnitude smaller for both flames than seen for simple hydrocarbon fuels (Ethylene, ethane, propene, and propane).
V. M. Rivilla - One of the best experts on this subject based on the ideXlab platform.
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on the chemical ladder of esters detection and formation of Ethyl Formate in the w51 e2 hot molecular core
Astronomy and Astrophysics, 2017Co-Authors: V. M. Rivilla, Maria T. Beltrán, Francesco Fontani, Paola Caselli, J Martinpintado, R. CesaroniAbstract:Context. In recent years, the detection of organic molecules with increasing complexity and potential biological relevance is opening the possibility to understand the formation of the building blocks of life in the interstellar medium. One of the families of molecules of substantial astrobiological interest are the esters. The simplest ester, mEthyl Formate (CH 3 OCHO), is rather abundant in star-forming regions. The next step in the chemical complexity of esters is Ethyl Formate, C 2 H 5 OCHO. Despite the increase in sensitivity of current telescopes, the detection of complex molecules with more than ten atoms such as C 2 H 5 OCHO is still a challenge. Only two detections of this species have been reported so far, which strongly limits our understanding of how complex molecules are formed in the interstellar medium. New detections towards additional sources with a wide range of physical conditions are crucial to differentiate between competing chemical models based on dust grain surface and gas-phase chemistry. Aims. We have searched for Ethyl Formate towards the W51 e2 hot molecular core, one of the most chemically rich sources in the Galaxy and one of the most promising regions to study prebiotic chemistry, especially after the recent discovery of the P−O bond, key in the formation of DNA. Methods. We have analyzed a spectral line survey towards the W51 e2 hot molecular core, which covers 44 GHz in the 1, 2 and 3 mm bands, carried out with the IRAM 30 m telescope. Results. We report the detection of the trans and gauche conformers of Ethyl Formate. A local thermodynamic equilibrium analysis indicates that the excitation temperature is 78 ± 10 K and that the two conformers have similar source-averaged column densities of (2.0 ± 0.3) × 10 -16 cm -2 and an abundance of ~10 -8 . We compare for the first time the observed molecular abundances of Ethyl Formate with different competing chemical models based on grain surface and gas-phase chemistry. Conclusions. We propose that grain-surface chemistry may have a dominant role in the formation of Ethyl Formate (and other complex organic molecules) in hot molecular cores, rather than reactions in the gas phase.
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On the chemical ladder of esters. Detection and formation of Ethyl Formate in the W51 e2 hot molecular core
Astronomy & Astrophysics, 2017Co-Authors: V. M. Rivilla, Maria T. Beltrán, Jesús Martín-pintado, Francesco Fontani, Paola Caselli, R. CesaroniAbstract:The detection of organic molecules with increasing complexity and potential biological relevance is opening the possibility to understand the formation of the building blocks of life in the interstellar medium. One of the families of molecules with astrobiological interest are the esters, whose simplest member, mEthyl Formate, is rather abundant in star-forming regions. The next step in the chemical complexity of esters is Ethyl Formate, C$_2$H$_5$OCHO. Only two detections of this species have been reported so far, which strongly limits our understanding of how complex molecules are formed in the interstellar medium. We have searched for Ethyl Formate towards the W51 e2 hot molecular core, one of the most chemically rich sources in the Galaxy and one of the most promising regions to study prebiotic chemistry, especially after the recent discovery of the P$-$O bond, key in the formation of DNA. We have analyzed a spectral line survey towards the W51 e2 hot molecular core, which covers 44 GHz in the 1, 2 and 3 mm bands, carried out with the IRAM 30m telescope. We report the detection of the trans and gauche conformers of Ethyl Formate. A Local Thermodynamic Equilibrium analysis indicates that the excitation temperature is 78$\pm$10 K and that the two conformers have similar source-averaged column densities of (2.0$\pm$0.3)$\times$10$^{16}$ cm$^{-2}$ and an abundance of $\sim$10$^{-8}$. We compare the observed molecular abundances of Ethyl Formate with different competing chemical models based on grain surface and gas-phase chemistry. We propose that grain-surface chemistry may have a dominant role in the formation of Ethyl Formate (and other complex organic molecules) in hot molecular cores, rather than reactions in the gas phase.
Patrick Osswald - One of the best experts on this subject based on the ideXlab platform.
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isomer specific fuel destruction pathways in rich flames of mEthyl acetate and Ethyl Formate and consequences for the combustion chemistry of esters
Journal of Physical Chemistry A, 2007Co-Authors: Patrick Osswald, Ulf Struckmeier, Tina Kasper, Katharina Kohsehoinghaus, Juan Wang, Terrill A Cool, Nils Hansen, Phillip R WestmorelandAbstract:The influences of fuel-specific destruction pathways on flame chemistry are determined for two isomeric ester fuels, mEthyl acetate, CH3(CO)OCH3, and Ethyl Formate, H(CO)OC2H5, used as model representatives for biodiesel compounds, and their potential for forming air pollutants is addressed. Measurements are presented of major and intermediate species mole fractions in premixed, laminar flat flames using molecular-beam sampling and isomer-selective VUV-photoionization mass spectrometry. The observed intermediate species concentrations depend crucially on decomposition of the different radicals formed initially from the fuels. The mEthyl acetate structure leads to preferential formation of formaldehyde, while the Ethyl Formate isomer favors the production of acetaldehyde. Ethyl Formate also yields higher concentrations of the C2 species (C2H2 and C2H4) and C4 species (C4H2 and C4H4). Benzene concentrations, while larger for Ethyl Formate, are at least an order of magnitude smaller for both flames than seen...
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isomer specific fuel destruction pathways in rich flames of mEthyl acetate and Ethyl Formate and consequences for the combustion chemistry of esters
Journal of Physical Chemistry A, 2007Co-Authors: Patrick Osswald, Ulf Struckmeier, Tina Kasper, Katharina Kohsehoinghaus, Juan Wang, Terrill A Cool, Nils Hansen, Phillip R WestmorelandAbstract:The influences of fuel-specific destruction pathways on flame chemistry are determined for two isomeric ester fuels, mEthyl acetate, CH3(CO)OCH3, and Ethyl Formate, H(CO)OC2H5, used as model representatives for biodiesel compounds, and their potential for forming air pollutants is addressed. Measurements are presented of major and intermediate species mole fractions in premixed, laminar flat flames using molecular-beam sampling and isomer-selective VUV-photoionization mass spectrometry. The observed intermediate species concentrations depend crucially on decomposition of the different radicals formed initially from the fuels. The mEthyl acetate structure leads to preferential formation of formaldehyde, while the Ethyl Formate isomer favors the production of acetaldehyde. Ethyl Formate also yields higher concentrations of the C2 species (C2H2 and C2H4) and C4 species (C4H2 and C4H4). Benzene concentrations, while larger for Ethyl Formate, are at least an order of magnitude smaller for both flames than seen for simple hydrocarbon fuels (Ethylene, ethane, propene, and propane).
Paola Caselli - One of the best experts on this subject based on the ideXlab platform.
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on the chemical ladder of esters detection and formation of Ethyl Formate in the w51 e2 hot molecular core
Astronomy and Astrophysics, 2017Co-Authors: V. M. Rivilla, Maria T. Beltrán, Francesco Fontani, Paola Caselli, J Martinpintado, R. CesaroniAbstract:Context. In recent years, the detection of organic molecules with increasing complexity and potential biological relevance is opening the possibility to understand the formation of the building blocks of life in the interstellar medium. One of the families of molecules of substantial astrobiological interest are the esters. The simplest ester, mEthyl Formate (CH 3 OCHO), is rather abundant in star-forming regions. The next step in the chemical complexity of esters is Ethyl Formate, C 2 H 5 OCHO. Despite the increase in sensitivity of current telescopes, the detection of complex molecules with more than ten atoms such as C 2 H 5 OCHO is still a challenge. Only two detections of this species have been reported so far, which strongly limits our understanding of how complex molecules are formed in the interstellar medium. New detections towards additional sources with a wide range of physical conditions are crucial to differentiate between competing chemical models based on dust grain surface and gas-phase chemistry. Aims. We have searched for Ethyl Formate towards the W51 e2 hot molecular core, one of the most chemically rich sources in the Galaxy and one of the most promising regions to study prebiotic chemistry, especially after the recent discovery of the P−O bond, key in the formation of DNA. Methods. We have analyzed a spectral line survey towards the W51 e2 hot molecular core, which covers 44 GHz in the 1, 2 and 3 mm bands, carried out with the IRAM 30 m telescope. Results. We report the detection of the trans and gauche conformers of Ethyl Formate. A local thermodynamic equilibrium analysis indicates that the excitation temperature is 78 ± 10 K and that the two conformers have similar source-averaged column densities of (2.0 ± 0.3) × 10 -16 cm -2 and an abundance of ~10 -8 . We compare for the first time the observed molecular abundances of Ethyl Formate with different competing chemical models based on grain surface and gas-phase chemistry. Conclusions. We propose that grain-surface chemistry may have a dominant role in the formation of Ethyl Formate (and other complex organic molecules) in hot molecular cores, rather than reactions in the gas phase.
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On the chemical ladder of esters. Detection and formation of Ethyl Formate in the W51 e2 hot molecular core
Astronomy & Astrophysics, 2017Co-Authors: V. M. Rivilla, Maria T. Beltrán, Jesús Martín-pintado, Francesco Fontani, Paola Caselli, R. CesaroniAbstract:The detection of organic molecules with increasing complexity and potential biological relevance is opening the possibility to understand the formation of the building blocks of life in the interstellar medium. One of the families of molecules with astrobiological interest are the esters, whose simplest member, mEthyl Formate, is rather abundant in star-forming regions. The next step in the chemical complexity of esters is Ethyl Formate, C$_2$H$_5$OCHO. Only two detections of this species have been reported so far, which strongly limits our understanding of how complex molecules are formed in the interstellar medium. We have searched for Ethyl Formate towards the W51 e2 hot molecular core, one of the most chemically rich sources in the Galaxy and one of the most promising regions to study prebiotic chemistry, especially after the recent discovery of the P$-$O bond, key in the formation of DNA. We have analyzed a spectral line survey towards the W51 e2 hot molecular core, which covers 44 GHz in the 1, 2 and 3 mm bands, carried out with the IRAM 30m telescope. We report the detection of the trans and gauche conformers of Ethyl Formate. A Local Thermodynamic Equilibrium analysis indicates that the excitation temperature is 78$\pm$10 K and that the two conformers have similar source-averaged column densities of (2.0$\pm$0.3)$\times$10$^{16}$ cm$^{-2}$ and an abundance of $\sim$10$^{-8}$. We compare the observed molecular abundances of Ethyl Formate with different competing chemical models based on grain surface and gas-phase chemistry. We propose that grain-surface chemistry may have a dominant role in the formation of Ethyl Formate (and other complex organic molecules) in hot molecular cores, rather than reactions in the gas phase.