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Acceso Abierto
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.
Acceso Abierto
Mimicking the Martian Hydrological Cycle: A Set-Up to Introduce Liquid Water in Vacuum
(Multidisciplinary Digital Publishing Institute (MDPI), 2020-10-29) Sobrado, J. M.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI)
Liquid water is well known as the life ingredient as a solvent. However, so far, it has only been found in liquid state on this planetary surface. The aim of this experiment and technological development was to test if a moss sample is capable of surviving in Martian conditions. We built a system that simulates the environmental conditions of the red planet including its hydrological cycle. This laboratory facility enables us to control the water cycle in its three phases through temperature, relative humidity, hydration, and pressure with a system that injects water droplets into a vacuum chamber. We successfully simulated the daytime and nighttime of Mars by recreating water condensation and created a layer of superficial ice that protects the sample against external radiation and minimizes the loss of humidity due to evaporation to maintain a moss sample in survival conditions in this extreme environment. We performed the simulations with the design and development of different tools that recreate Martian weather in the MARTE simulation chamber.
Restringido
Prevalence of non-aromatic carbonaceous molecules in the inner regions of circumstellar envelopes
(Nature, 2019-10-21) Martínez, Lidia; Santoro, G.; Merino, P.; Accolla, M.; Lauwaet, K.; Sobrado, J. M.; Sabbah, H.; Peláez, R. J.; Herrero, V. J.; Tanarro, I.; Agúndez, Marcelino; Martín Jiménez, Alberto; Otero, Roberto; Ellis, G. J.; Joblin, C.; Cernicharo, J.; Martín-Gago, J. A.; Instituto Nacional de Técnica Aeroespacial (INTA); European Commission (EC); Agencia Estatal de Investigación (AEI)
Evolved stars are foundries of chemical complexity, gas and dust that provide the building blocks of planets and life, and dust nucleation first occurs in their photosphere. The circumstellar regions enveloping these stars, despite their importance, remain hidden to many observations, and dust formation processes are therefore still poorly understood. Laboratory astrophysics provides complementary routes to unveil these chemical processes, but most experiments rely on combustion or plasma decomposition of molecular precursors under physical conditions far removed from those in space. To reproduce and characterize the bottom-up dust formation process, we have built an ultra-high vacuum machine combining atomic gas aggregation with advanced in situ characterization techniques. We show that carbonaceous dust analogues that formed from low-pressure gas-phase condensation of carbon atoms in a hydrogen atmosphere, in a ratio of carbon to molecular hydrogen similar to that reported for evolved stars, lead to the formation of amorphous carbon nanograins and aliphatic carbon clusters. Aromatic species and fullerenes do not form effectively under these conditions, raising implications for a revision of the chemical mechanisms taking place in circumstellar envelopes.
Acceso Abierto
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.
Acceso Abierto
Enantiopure distorted ribbon-shaped nanographene combining two-photon absorption-based upconversion and circularly polarized luminescence†
(Royal Society of Chemistry (RSC), 2018-03-14) Cruz, C. M.; Márquez, I. R.; Mariz, I. F. A.; Blanco, V.; Sánchez-Sánchez, C.; Sobrado, J. M.; Martín Gago, J. A.; Cuerva, J. M.; Maçôas, E.; Campaña, A. G.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Ciencia e Innovación (MICINN); European Research Council (ERC); Fundacao para a Ciencia e a Tecnologia (FCT)
Herein we describe a distorted ribbon-shaped nanographene exhibiting unprecedented combination of optical properties in graphene-related materials, namely upconversion based on two-photon absorption (TPA-UC) together with circularly polarized luminescence (CPL). The compound is a graphene molecule of ca. 2 nm length and 1 nm width with edge defects that promote the distortion of the otherwise planar lattice. The edge defects are an aromatic saddle-shaped ketone unit and a [5]carbohelicene moiety. This system is shown to combine two-photon absorption and circularly polarized luminescence and a remarkably long emission lifetime of 21.5 ns. The [5]helicene is responsible for the chiroptical activity while the push–pull geometry and the extended network of sp2 carbons are factors favoring the nonlinear absorption. Electronic structure theoretical calculations support the interpretation of the results.
Acceso Abierto
Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept
(EDP Science, 2017-12-22) Tanarro, I.; Alemán, Belén; De Vicente, P.; Gallego, J. D.; Pardo, Juan R.; Santoro, G.; Lauwaet, K.; Tercero, Felix; Díaz Pulido, A.; Moreno, E.; Agúndez, Marcelino; Goicoechea, J. R.; Sobrado, J. M.; López, J. A.; Martínez, L.; Doménech, Jose Luis; Herrero, V. J.; Hernández, J. M.; Peláez, R. J.; López Pérez, Jose A.; Gómez González, J.; Alonso, J. L.; Jiménez, Elena; Teyssier, D.; Makasheva, Kremena; Castellanos, Marcelo; Joblin, C.; Martín Gago, J. A.; Cernicharo, J.; Ministerio de Economía y Competitividad (MINECO)
We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactors and the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40 cm long gas cell placed in the beam path of the Aries 40 m radio telescope receivers operating in the 41–49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS, CS, SO2 (<10-3 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.
Restringido
Mimicking Mars: A vacuum simulation chamber for testing environmental instrumentation for Mars exploration
(AIP Publishing, 2014-03-25) Sobrado, J. M.; Martín Soler, J.; Martín Gago, J. A.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)
We have built a Mars environmental simulation chamber, designed to test new electromechanical devices and instruments that could be used in space missions. We have developed this environmental system aiming at validating the meteorological station Rover Environment Monitoring Station of NASA's Mars Science Laboratory mission currently installed on Curiosity rover. The vacuum chamber has been built following a modular configuration and operates at pressures ranging from 1000 to 10−6 mbars, and it is possible to control the gas composition (the atmosphere) within this pressure range. The device (or sample) under study can be irradiated by an ultraviolet source and its temperature can be controlled in the range from 108 to 423 K. As an important improvement with respect to other simulation chambers, the atmospheric gas into the experimental chamber is cooled at the walls by the use of liquid-nitrogen heat exchangers. This chamber incorporates a dust generation mechanism designed to study Martian-dust deposition while modifying the conditions of temperature, and UV irradiated.
Acceso Abierto
New results on thermal and photodesorption of CO ice using the novel InterStellar Astrochemistry Chamber (ISAC)
(EDP Science, 2010-11-09) Muñoz Caro, G. M.; Jiménez Escobar, A.; Martín Gago, J. A.; Rogero, Celia; Atienza, C.; Puertas, S.; Sobrado, J. M.; Torres Redondo, J.; Ministerio de Ciencia e Innovación (MICINN); Instituto Nacional de Técnica Aeroespacial (INTA)
Aims. We present the novel InterStellar Astrochemistry Chamber (ISAC), designed for studying solids (ice mantles, organics, and silicates) in interstellar and circumstellar environments: characterizing their physico-chemical properties and monitoring their evolution as caused by (i) vacuum-UV irradiation; (ii) cosmic ray irradiation; and (iii) thermal processing. Experimental study of thermal and photodesorption of the CO ice reported here simulates the freeze-out and desorption of CO on grains, providing new information on these processes. Methods. ISAC is an UHV set-up, with base pressure down to P = 2.5 × 10-11 mbar, where an ice layer is deposited at 7 K and can be UV-irradiated. The evolution of the solid sample was monitored by in situ transmittance FTIR spectroscopy, while the volatile species were monitored by QMS. Results. The UHV conditions of ISAC allow experiments under extremely clean conditions. Transmittance FTIR spectroscopy coupled to QMS proved to be ideal for in situ monitoring of ice processes that include radiation and thermal annealing. Thermal desorption of CO starting at 15 K, induced by the release of H2 from the CO ice, was observed. We measured the photodesorption yield of CO ice per incident photon at 7, 8, and 15 K, respectively yielding 6.4 ± 0.5 × 10-2, 5.4 ± 0.5 × 10-2, and 3.5 ± 0.5 × 10-2 CO molecules photon (7.3–10.5 eV)-1. Our value of the photodesorption yield of CO ice at 15 K is about one order of magnitude higher than the previous estimate. We confirmed that the photodesorption yield is constant during irradiation and independent of the ice thickness. Only below ~ 5 monolayers ice thickness the photodesorption rate decreases, which suggests that only the UV photons absorbed in the top 5 monolayers led to photodesorption. The measured CO photodesorption quantum yield at 7 K per absorbed photon in the top 5 monolayers is 3.4 molecules photon-1. Conclusions. Experimental values were used as input for a simple model of a quiescent cloud interior. Photodesorption seems to explain the observations of CO in the gas phase for densities below 3–7 × 104 cm-3. For the same density of a cloud, 3 × 104 cm-3, thermal desorption of CO is not triggered until T = 14.5 K. This has important implications for CO ice mantle build up in dark clouds.
Restringido
Interplay between Fast Diffusion and Molecular Interaction in the Formation of Self-Assembled Nanostructures of S-Cysteine on Au(111)
(ACS Publications, 2010-01-21) Mateo Martí, Eva; Rogero, Celia; González, César; Sobrado, J. M.; De Andrés, Pedro L.; Martín Gago, J. A.
We have studied the first stages leading to the formation of self-assembled monolayers of S-cysteine molecules adsorbed on a Au(111) surface. Density functional theory (DFT) calculations for the adsorption of individual cysteine molecules on Au(111) at room temperature show low-energy barriers all over the 2D Au(111) unit cell. As a consequence, cysteine molecules diffuse freely on the Au(111) surface and they can be regarded as a 2D molecular gas. The balance between molecule−molecule and molecule−substrate interactions induces molecular condensation and evaporation from the morphological surface structures (steps, reconstruction edges, etc.) as revealed by scanning tunnelling microscopy (STM) images. These processes lead progressively to the formation of a number of stable arrangements, not previously reported, such as single-molecular rows, trimers, and 2D islands. The condensation of these structures is driven by the aggregation of new molecules, stabilized by the formation of electrostatic interactions between adjacent NH3+ and COO− groups, together with adsorption at a slightly more favorable quasi-top site of the herringbone Au reconstruction.
Restringido
Modelling the kinetics and structural property evolution of a versatile reaction: aqueous HCN polymerization
(Royal Society of Chemistry (RSC), 2018-05-29) Fernández, Amparo; Ruiz Bermejo, Marta; De la Fuente, J. L.; Ministerio de Economía y Competitividad (MINECO); Instituto Nacional de Técnica Aeroespacial (INTA)
The kinetics of the reaction of the synthesis of HCN polymers in aqueous medium at high temperatures have been analysed to ascertain a suitable model for this material, for which it was recently demonstrated that prebiotic chemistry may now be adapted in the development of a new generation of high performance coatings and adhesives with biomedical applications. These experimental conditions were chosen for the simplicity of the reagents, being particularly convenient in regard to potential industrial scale-up of coating technology, where these polymers have revealed an interesting field of application. The kinetics of the precipitation polymerization of HCN in water were studied under isothermal conditions at four different temperatures between 75 °C and 90 °C throughout gravimetric measurements. The use of the Kamal–Sourour autocatalytic kinetic model was proposed, properly describing the overall formation process of this insoluble HCN polymer. All of the kinetic parameters, including reaction orders, kinetic constants and activation energy, were determined for the cross-linking polymerization reaction under study, and a relevant autocatalysis effect was observed. An isoconversion method was also used to analyse the variation of the global activation energy with conversion; and characterization by means of elemental analysis, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) was carried out. This study demonstrates the autocatalytic, robust and straightforward character of this heterogeneous aqueous HCN polymerization, and to the best of our knowledge, this report describes the first time that a systematic and extended kinetic analysis has been conducted to obtain a more comprehensive and deeper understanding of this complex reaction, which is of great interest to the origin of life and, currently, to materials science.
Acceso Abierto
Prebiotic chemistry in neutral/reduced-alkaline gas-liquid interfaces
(Springer Nature, 2019-02-13) Mompeán, Cristina; Roig Marín-Yaseli, Margarita; Espigares, Patricia; González Toril, Elena; Zorzano, María Paz; Ruiz Bermejo, Marta; Ministerio de Economía y Competitividad (MINECO); Instituto Nacional de Técnica Aeroespacial (INTA)
The conditions for the potential abiotic formation of organic compounds from inorganic precursors have great implications for our understanding of the origin of life on Earth and for its possible detection in other environments of the Solar System. It is known that aerosol-interfaces are effective at enhancing prebiotic chemical reactions, but the roles of salinity and pH have been poorly investigated to date. Here, we experimentally demonstrate the uniqueness of alkaline aerosols as prebiotic reactors that produce an undifferentiated accumulation of a variety of multi-carbon biomolecules resulting from high-energy processes (in our case, electrical discharges). Using simulation experiments, we demonstrate that the detection of important biomolecules in tholins increases when plausible and particular local planetary environmental conditions are simulated. A greater diversity in amino acids, carboxylic acids, N-heterocycles, and ketoacids, such as glyoxylic and pyruvic acid, was identified in tholins synthetized from reduced and neutral atmospheres in the presence of alkaline aqueous aerosols than that from the same atmospheres but using neutral or acidic aqueous aerosols.
Restringido
HCN-derived polymers from thermally induced polymerization of diaminomaleonitrile: A non-enzymatic peroxide sensor based on prebiotic chemistry
(Elsevier, 2021-11-24) Ruiz Bermejo, Marta; García Armada, Pilar; Mateo Martí, Eva; De la Fuente, J. L.; Ministerio de Ciencia e Innovación (MICINN); Instituto Nacional de Técnica Aeroespacial (INTA); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
HCN-derived polymers have recently attracted considerable attention due to their promising applications as multifunctional materials. This study, inspired by plausible early Earth geochemical conditions, describes a strategy to synthesize them from the self-initiated thermal bulk polymerization of the HCN tetramer, diaminomaleonitrile (DAMN), with outstanding sensing properties. These conjugated polymers were obtained through noncatalysed and simple isothermal reactions at 170 °C in the solid-state, and experiments at 190 °C permitted polymerization in the melt. Both processes are highly efficient, allowing quantitative yields of the end products. The conductivity properties of both polymers have been explored to show their high potential, especially DAMN polymers synthesized in melt, as nonenzymatic peroxide sensors. To better understand the differences found between the two series, structural characterisation was carried out using compositional data, Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) and X-ray photoelectron (XPS) spectroscopies, and X-ray diffraction (XRD) measurements. The interpretation of the structural data suggests that a two-dimensional (2-D) macrostructure based on N-heterocyclics is predominant regardless of the state of monomer aggregation during the course of polymerization, but preferably formed in the melt. The morphological and thermal stability properties of the polymers based on DAMN were also evaluated. Finally, the most likely mechanisms based on the dehydrocyanation and deamination reactions that take place during the polymerization reaction are proposed. This study demonstrates the robust and straightforward character of these thermally activated polymerizations, which are of interest to chemical evolution research and to current materials and surface science.
Acceso Abierto
Semiconducting Soft Submicron Particles from the Microwave-Driven Polymerization of Diaminomaleonitrile
(Multidisciplinary Digital Publishing Institute (MDPI), 2022-08-24) Ruiz Bermejo, Marta; García Armada, Pilar; Valles González, M. P.; De la Fuente, J. L.; Ministerio de Ciencia e Innovación (MICINN); Instituto Nacional de Técnica Aeroespacial (INTA); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The polymers based on diaminomaleonitrile (DAMN polymers) are a special group within an extensive set of complex substances, namely HCN polymers (DAMN is the formal tetramer of the HCN), which currently present a growing interest in materials science. Recently, the thermal polymerizability of DAMN has been reported, both in an aqueous medium and in bulk, offering the potential for the development of capacitors and biosensors, respectively. In the present work, the polymerization of this plausible prebiotic molecule has been hydrothermally explored using microwave radiation (MWR) via the heating of aqueous DAMN suspensions at 170–190 °C. In this way, polymeric submicron particles derived from DAMN were obtained for the first time. The structural, thermal decomposition, and electrochemical properties were also deeply evaluated. The redox behavior was characterized from DMSO solutions of these highly conjugated macromolecular systems and their potential as semiconductors was described. As a result, new semiconducting polymeric submicron particles were synthetized using a very fast, easy, highly robust, and green-solvent process. These results show a new example of the great potential of the polymerization assisted by MWR associated with the HCN-derived polymers, which has a dual interest both in chemical evolution and as functional materials.
Acceso Abierto
Multivariate Analysis Applied to Microwave-Driven Cyanide Polymerization: A Statistical View of a Complex System
(Multidisciplinary Digital Publishing Institute (MDPI), 2023-01-12) Pérez Fernández, Cristina; González Toril, Elena; Mateo Martí, Eva; Ruiz Bermejo, Marta; Ministerio de Ciencia e Innovación (MICINN)
For the first time, chemometrics was applied to the recently reported microwave-driven cyanide polymerization. Fast, easy, robust, low-cost, and green-solvent processes are characteristic of these types of reactions. These economic and environmental benefits, originally inspired by the constraints imposed by plausible prebiotic synthetic conditions, have taken advantage of the development of a new generation of HCN-derived multifunctional materials. HCN-derived polymers present tunable properties by temperature and reaction time. However, the apparently random behavior observed in the evolution of cyanide polymerizations, assisted by microwave radiation over time at different temperatures, leads us to study this highly complex system using multivariate analytical tools to have a proper view of the system. Two components are sufficient to explain between 84 and 98% of the total variance in the data in all principal component analyses. In addition, two components explain more than 91% of the total variance in the data in the case of principal component analysis for categorical data. These consistent statistical results indicate that microwave-driven polymerization is a more robust process than conventional thermal syntheses but also that plausible prebiotic chemistry in alkaline subaerial environments could be more complex than in the aerial part of these systems, presenting a clear example of the “messy chemistry” approach of interest in the research about the origins of life. In addition, the methodology discussed herein could be useful for the data analysis of extraterrestrial samples and for the design of soft materials, in a feedback view between prebiotic chemistry and materials science.
Restringido
Ammonium affects the wet chemical network of HCN: feedback between prebiotic chemistry and materials science
(Royal Society of Chemistry, 2023-06-21) De la Fuente, J. L.; Vega, Jorge; Mateo Martí, Eva; Valles González, M. P.; Ruiz Bermejo, Marta; Pérez Fernández, Cristina; Instituto Nacional de Técnica Aeroespacial (INTA); Universidad Complutense de Madrid (UCM); Agencia Estatal de Investigación (AEI); Consejo Superior de Investigaciones Científicas (CSIC); Ministerio de Ciencia, Innovación y Universidades (MICINN)
Prebiotic chemistry one-pot reactions, such as HCN-derived polymerizations, have been used as stimulating starting points for the generation of new multifunctional materials due to the simplicity of the processes, use of water as solvent, and moderate thermal conditions. Slight experimental variations in this special kind of polymerization tune the final properties of the products. Thus, herein, the influence of NH4Cl on the polymerization kinetics of cyanide under hydrothermal conditions and on the macrostructures and properties of this complex system is explored. The kinetics of the process is consistent with an autocatalytic model, but important variations in the polymerization reaction are observed according to a simple empirical model based on a Hill equation. The differences in the kinetic behaviour against NH4Cl were also revealed when the structural, morphological, thermal, electronic and magnetic properties of the synthesized cyanide polymers were compared, and these properties were evaluated by elemental analysis, FTIR, XPS, UV-vis, and ESR spectroscopies, X-ray diffraction, SEM and thermoanalytical techniques. As a result, this hydrothermal prebiotic polymerization is not only pH dependent, as previously thought, but also ammonium subservient. From this result, a hypothetical reaction mechanism was proposed, which involves the active participation of ammonium cations via formamidine and serves as a remarkable point against previous reports. The results discussed here expand the knowledge on HCN wet chemistry, offer an extended view of the relevant parameters during the simulation of hydrothermal scenarios and describe the production of promising paramagnetic and semiconducting materials inspired by prebiotic chemistry.
Acceso Abierto
Kinetic Study of the Effective Thermal Polymerization of a Prebiotic Monomer: Aminomalononitrile
(Multidisciplinary Digital Publishing Institute, 2023-01-17) Hortelano, C.; Ruiz Bermejo, Marta; De la Fuente, J. L.; Agencia Estatal de Investigación (AEI); Ministerio de Ciencia e Innovación (MICINN)
Acceso Abierto
Prebiotic synthesis of noncanonical nucleobases under plausible alkaline hydrothermal conditions
(Springer Nature, 2022-09-07) Pérez Fernández, Cristina; Vega, Jorge; Rayo Pizarroso, P.; Mateo Martí, Eva; Ruiz Bermejo, Marta; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Ministerio de Ciencia, Innovación y Universidades (MICIN); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Herein, the potential of alkaline hydrothermal environments for the synthesis of possible ancestral pre-RNA nucleobases using cyanide as a primary source of carbon and nitrogen is described. Water cyanide polymerizations were assisted by microwave radiation to obtain high temperature and a relatively high pressure (MWR, 180 °C, 15 bar) and were also carried out using a conventional thermal system (CTS, 80 °C, 1 bar) to simulate subaerial and aerial hydrothermal conditions, respectively, on the early Earth. For these syntheses, the initial concentration of cyanide and the diffusion effects were studied. In addition, it is well known that hydrolysis conditions are directly related to the amount and diversity of organic molecules released from cyanide polymers. Thus, as a first step, we studied the effect of several hydrolysis procedures, generally used in prebiotic chemistry, on some of the potential pre-RNA nucleobases of interest, together with some of their isomers and/or deamination products, also presumably formed in these complex reactions. The results show that the alkaline hydrothermal scenarios with a relatively constant pH are good geological scenarios for the generation of noncanonical nucleobases using cyanide as a prebiotic precursor.
Restringido
Air effect on both polymerization kinetics and thermal degradation properties of novel HCN polymers based on diaminomaleonitrile
(Elsevier, 2022-12) Hortelano, C.; Ruiz Bermejo, Marta; De la Fuente, J. L.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Ciencia, Innovación y Universidades (MICIN); Agencia Estatal de Investigación (AEI); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The impact of air on the bulk polymerization kinetics of diaminomaleonitrile (DAMN), tetramer of HCN, and thermal degradation properties of this resulting conjugated C=N polymeric system is investigated under different temperature regimes and environments. This study shows the effect of exposure to air and oxygen, time, temperature, and evolved gases during DAMN polymerization reactions, which can be suitably monitored by differential scanning calorimetry (DSC) through both dynamic and isothermal measurements. Thus, low heating rates and isothermal scans at 150-170 °C allow us to describe the solid-state polymerization (SSP) of DAMN, and those experiments at 190, 195 and 200 °C and higher heating runs define its melt polymerization (MP) behaviour. Both processes are highly efficient, possibly due to the self-acceleration nature of their kinetics, which is consistent with a three-step Šesták-Berggren (SB) model. The oxygen effect was analysed to determine their tolerance to this variable and confirm the nonradical nature of the mechanism under study. In addition, a detailed thermal characterization by simultaneous DSC/thermogravimetry coupled to mass spectrometry (TG-MS) of these singular polymeric systems obtained under air atmosphere has been completed, and the improvement of the thermal stability of those samples prepared by an SSP at lower temperature was confirmed. The present work offers lower-cost and simpler synthetic methods to obtain this novel class of promising multifunctional polymeric materials through highly efficient and very fast processes.
Acceso Abierto
A radio-jet driven outflow in the Seyfert 2 galaxy NGC 2110?
(EDP Sciences, 2023-05-10) Peralta de Arriba, L.; Alonso Herrero, A.; García Burillo, S.; García Bernete, I.; Villar Martín, M.; García Lorenzo, B.; Davies, R. I.; Rosario, D.; Hönig, S. F.; Levenson, N. A.; Packham, C.; Ramos Almeida, C.; Pereira Santaella, M.; Audibert, A.; Bellocchi, E.; Hicks, E. K. S.; Labiano, Á.; Ricci, C.; Rigopoulou, D.; European Commission (EC); Gobierno de Canarias; University of Oxford; Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Ministerio de Ciencia e Innovación (MICINN); Science and Technology Facilities Council (STFC); Centros de Excelencia Severo Ochoa, CENTRO NACIONAL DE BIOTECNOLOGIA (CNB), SEV-2017-0712
We present a spatially-resolved study of the ionised gas in the central 2 kpc of the Seyfert 2 galaxy NGC 2110 and investigate the role of its moderate luminosity radio jet (kinetic radio power of $P_\mathrm{jet} = 2.3 \times 10^{43}\mathrm{erg\ s^{-1}}$). We use new optical integral-field observations taken with the MEGARA spectrograph at GTC. We fit the emission lines with a maximum of two Gaussian components, except at the AGN position where we used three. Aided by existing stellar kinematics, we use the observed velocity and velocity dispersion of the emission lines to classify the different kinematic components. The disc component is characterised by lines with $\sigma \sim 60-200\ \mathrm{km\ s^{-1}}$. The outflow component has typical values of $\sigma \sim 700\ \mathrm{km\ s^{-1}}$ and is confined to the central 400 pc, which is coincident with linear part of the radio jet detected in NGC 2110. At the AGN position, the [O III]$\lambda$5007 line shows high velocity components reaching at least $1000\ \mathrm{km\ s^{-1}}$. This and the high velocity dispersions indicate the presence of outflowing gas outside the galaxy plane. Spatially-resolved diagnostic diagrams reveal mostly LI(N)ER-like excitation in the outflow and some regions in the disc, which could be due to the presence of shocks. However, there is also Seyfert-like excitation beyond the bending of the radio jet, probably tracing the edge of the ionisation cone that intercepts with the disc of the galaxy. NGC 2110 follows well the observational trends between the outflow properties and the jet radio power found for a few nearby Seyfert galaxies. All these pieces of information suggest that part of observed ionised outflow in NGC 2110 might be driven by the radio jet. However, the radio jet was bent at radial distances of 200 pc (in projection) from the AGN, and beyond there, most of the gas in the galaxy disc is rotating.
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CO2 adsorption capacities of amine-functionalized microporous silica nanoparticles
(Elsevier, 2021-11-06) Cueto Díaz, Eduardo J.; Suárez García, Fabián; Gálvez Martínez, Santos; Valles González, M. P.; Mateo Martí, Eva; Ministerio de Economía y Competitividad (MINECO); Gobierno del Principado de Asturias
Efforts on CO2 capture have intensified as climate change compromises ecosystems and biodiversity. Therefore, it is crucial to develop different methods for CO2 sequestration to improve solid sorbent capabilities (NPs). To this end, the surface of 200-nm silica nanoparticles (SiO2NPs) was covalently anchored with aminated ligands, 3-aminopropyltriethoxysilane (APTES), poly(amidoamine) dendrimers (PAMAM) and a short peptide comprising two lysine units, aiming for CO2 adsorption over a wide range of pressures. Our goal was to explore the influence of functional chemical groups (attached to the SiO2NPs) on CO2 sequestration. The observed results showed that at low and high CO2 gas pressure conditions, typical APTES functionalized SiO2Np surpassed the CO2 adsorption capacities of dendritic and peptide-based nanoparticles bearing amine-polymer functionalities, a remarkable effect that was investigated in this work. In addition, a convenient and facile method to decorate and quantify SiO2 nanoparticles with PAMAM and a short peptide is reported.

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