Proyecto de Investigación: MAT2017-85089-C2-1-R
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MAT2017-85089-C2-1-R
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INFRA-ICE: An ultra-high vacuum experimental station for laboratory astrochemistry
(American Institute of Physics, 2020-12-02) Santoro, G.; Sobrado, J. M.; Tajuelo Castilla, G.; Accolla, M.; Martínez, L.; Azpeitia, J.; Lauwaet, K.; Cernicharo, J.; Ellis, G. J.; Martín Gago, J. A.; European Commission (EC); Spanish Research Agency (AEI); Comunidad de Madrid; Castilla, G. [0000-0001-7877-2543]; Cernicharo, J. [0000-0002-3518-2524]; Martín Gago, J. A. [0000-0003-2663-491X]; Santoro, G. [0000-0003-4751-2209]; Martínez Orellana, L. [0000-0002-9370-2962]; Sobrado, J. M. [0000-0002-7359-0262]; Ellis, G. [0000-0003-4851-6092]
Laboratory astrochemistry aims at simulating, in the laboratory, some of the chemical and physical processes that operate in different regions of the universe. Amongst the diverse astrochemical problems that can be addressed in the laboratory, the evolution of cosmic dust grains in different regions of the interstellar medium (ISM) and its role in the formation of new chemical species through catalytic processes present significant interest. In particular, the dark clouds of the ISM dust grains are coated by icy mantles and it is thought that the ice-dust interaction plays a crucial role in the development of the chemical complexity observed in space. Here, we present a new ultra-high vacuum experimental station devoted to simulating the complex conditions of the coldest regions of the ISM. The INFRA-ICE machine can be operated as a standing alone setup or incorporated in a larger experimental station called Stardust, which is dedicated to simulate the formation of cosmic dust in evolved stars. As such, INFRA-ICE expands the capabilities of Stardust allowing the simulation of the complete journey of cosmic dust in space, from its formation in asymptotic giant branch stars to its processing and interaction with icy mantles in molecular clouds. To demonstrate some of the capabilities of INFRA-ICE, we present selected results on the ultraviolet photochemistry of undecane (C11H24) at 14 K. Aliphatics are part of the carbonaceous cosmic dust, and recently, aliphatics and short n-alkanes have been detected in situ in the comet 67P/Churyumov-Gerasimenko.
Precisely controlled fabrication, manipulation and in-situ analysis of Cu based nanoparticles
(Nature, 2018-05-08) Martínez, Lidia; Lauwaet, K.; Santoro, G.; Sobrado, J. M.; Peláez, R. J.; Herrero, V. J.; Tanarro, I.; Ellis, G. J.; Cernicharo, J.; Joblin, C.; Huttel, Y.; Martín-Gago, J. A.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO); European Commission (EC); Agencia Estatal de Investigación (AEI)
The increasing demand for nanostructured materials is mainly motivated by their key role in a wide variety of technologically relevant fields such as biomedicine, green sustainable energy or catalysis. We have succeeded to scale-up a type of gas aggregation source, called a multiple ion cluster source, for the generation of complex, ultra-pure nanoparticles made of different materials. The high production rates achieved (tens of g/day) for this kind of gas aggregation sources, and the inherent ability to control the structure of the nanoparticles in a controlled environment, make this equipment appealing for industrial purposes, a highly coveted aspect since the introduction of this type of sources. Furthermore, our innovative UHV experimental station also includes in-flight manipulation and processing capabilities by annealing, acceleration, or interaction with background gases along with in-situ characterization of the clusters and nanoparticles fabricated. As an example to demonstrate some of the capabilities of this new equipment, herein we present the fabrication of copper nanoparticles and their processing, including the controlled oxidation (from Cu0 to CuO through Cu2O, and their mixtures) at different stages in the machine.
Broad-band high-resolution rotational spectroscopy for laboratory astrophysics
(EDP Science, 2019-06-07) Cernicharo, J.; Gallego, J. D.; López Pérez, Jose A.; Tercero, Felix; Tanarro, I.; Beltrán, F.; De Vicente, P.; Lauwaet, K.; Alemán, Belén; Moreno, E.; Herrero, V. J.; Doménech, Jose Luis; Ramírez, S. I.; Bermúdez, Celina; Peláez, R. J.; Patino Esteban, Marina; López Fernández, Isaac; García Álvaro, Sonia; García Carreño, Pablo; Cabezas, Carlos; Malo, Inmaculada; Amils, R.; Sobrado, J. M.; Díez González, C.; Hernandéz, Jose M.; Tercero, B.; Santoro, G.; Martínez, L.; Castellanos, Marcelo; Vaquero Jiménez, B.; Pardo, Juan R.; Barbas, L.; López Fernández, Jose Antonio; Aja, B.; Leuther, A.; Martín-Gago, J. A.; Instituto Nacional de Técnica Aeroespacial (INTA); European Commission (EC); Agencia Estatal de Investigación (AEI)
We present a new experimental set-up devoted to the study of gas phase molecules and processes using broad-band high spectral resolution rotational spectroscopy. A reactor chamber is equipped with radio receivers similar to those used by radio astronomers to search for molecular emission in space. The whole range of the Q (31.5–50 GHz) and W bands (72–116.5 GHz) is available for rotational spectroscopy observations. The receivers are equipped with 16 × 2.5 GHz fast Fourier transform spectrometers with a spectral resolution of 38.14 kHz allowing the simultaneous observation of the complete Q band and one-third of the W band. The whole W band can be observed in three settings in which the Q band is always observed. Species such as CH3CN, OCS, and SO2 are detected, together with many of their isotopologues and vibrationally excited states, in very short observing times. The system permits automatic overnight observations, and integration times as long as 2.4 × 105 s have been reached. The chamber is equipped with a radiofrequency source to produce cold plasmas, and with four ultraviolet lamps to study photochemical processes. Plasmas of CH4, N2, CH3CN, NH3, O2, and H2, among other species, have been generated and the molecular products easily identified by the rotational spectrum, and via mass spectrometry and optical spectroscopy. Finally, the rotational spectrum of the lowest energy conformer of CH3CH2NHCHO (N-ethylformamide), a molecule previously characterized in microwave rotational spectroscopy, has been measured up to 116.5 GHz, allowing the accurate determination of its rotational and distortion constants and its search in space.
The Chemistry of Cosmic Dust Analogs from C, C2, and C2H2 in C-rich Circumstellar Envelopes
(The Institute of Physics (IOP), 2020-06-02) Santoro, G.; Martínez, L.; Lauwaet, K.; Accolla, M.; Tajuelo Castilla, G.; Merino, P.; Sobrado, J. M.; Peláez, R. J.; Herrero, V. J.; Tanarro, I.; Mayoral, Á.; Agúndez, Marcelino; Sabbah, H.; Joblin, C.; Cernicharo, J.; Martín Gago, J. A.; European Commission (EC); Comunidad de Madrid; Ministerio de Economía y Competitividad (MINECO); Santorio, G. [0000-0003-4751-2209]; Accolla, M. [0000-0002-9509-5967]; Agúndez, M. [0000-0003-3248-3564]; Sabbah, H. [0000-0001-5722-4388]; Joblin, C. [0000-0003-1561-6118]; Cernicharo, J. [0000-0002-3518-2524]; Martín Gago, J. M. [0000-0003-2663-491X]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Interstellar carbonaceous dust is mainly formed in the innermost regions of circumstellar envelopes around carbon-rich asymptotic giant branch stars (AGBs). In these highly chemically stratified regions, atomic and diatomic carbon, along with acetylene, are the most abundant species after H and CO. In a previous study, we addressed the chemistry of carbon (C and C) with H showing that acetylene and aliphatic species form efficiently in the dust formation region of carbon-rich AGBs whereas aromatics do not. Still, acetylene is known to be a key ingredient in the formation of linear polyacetylenic chains, benzene, and polycyclic aromatic hydrocarbons (PAHs), as shown by previous experiments. However, these experiments have not considered the chemistry of carbon (C and C) with CH. In this work, by employing a sufficient amount of acetylene, we investigate its gas-phase interaction with atomic and diatomic carbon. We show that the chemistry involved produces linear polyacetylenic chains, benzene, and other PAHs, which are observed with high abundances in the early evolutionary phase of planetary nebulae. More importantly, we have found a nonnegligible amount of pure and hydrogenated carbon clusters as well as aromatics with aliphatic substitutions, both being a direct consequence of the addition of atomic carbon. The incorporation of alkyl substituents into aromatics can be rationalized by a mechanism involving hydrogen abstraction followed by methyl addition. All the species detected in the gas phase are incorporated into nanometric-sized dust analogs, which consist of a complex mixture of sp, sp, and sp hydrocarbons with amorphous morphology.
Morphology Clustering Software for AFM Images, Based on Particle Isolation and Artificial Neural Networks
(Institute of Electrical and Electronics Engineers, 2019-11-04) Delgado, A.; Moreno, M.; Vázquez, L. F.; Martín Gago, J. A.; Briones, C.; Ministerio de Economía y Competitividad (MINECO); Comunidad de Madrid; Agencia Estatal de Investigación (AEI); Delgado, A. [0000-0003-4868-3712]; Moreno, M. [0000-0002-6065-4095]; MartínGago, J. A. [0000-0003-2663-491X]; Briones, C. [0000-0003-2213-8353]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Advanced microscopy techniques currently allow scientists to visualize biomolecules at high resolution. Among them, atomic force microscopy (AFM) shows the advantage of imaging molecules in their native state, without requiring any staining or coating of the sample. Biopolymers, including proteins and structured nucleic acids, are flexible molecules that can fold into alternative conformations for any given monomer sequence, as exemplified by the different three-dimensional structures adopted by RNA in solution. Therefore, the manual analysis of images visualized by AFM and other microscopy techniques becomes very laborious and time-consuming (and may also be inadvertently biased) when large populations of biomolecules are studied. Here we present a novel morphology clustering software, based on particle isolation and artificial neural networks, which allows the automatic image analysis and classification of biomolecules that can show alternative conformations. It has been tested with a set of AFM images of RNA molecules (a 574 nucleotides-long functional region of the hepatitis C virus genome that contains its internal ribosome entry site element) structured in folding buffers containing 0, 2, 4, 6 or 10 mM Mg 2+ . The developed software shows a broad applicability in the microscopy-based analysis of biopolymers and other complex biomolecules.
