Improved determination of the 1(0)-0(0) rotational frequency of NH3D+ from the high resolution spectrum of the v4 infrared band

The high resolution spectrum of the v4 band of NH3D+ has been measured by difference frequency IR laser spectroscopy in a multipass hollow cathode discharge cell. From the set of molecular constants obtained from the analysis of the spectrum, a value of 262817(6) MHz (3sigma) has been derived for the frequency of the 1(0)-0(0) rotational transition. This value supports the assignment to NH3D+ of lines at 262816.7 MHz recorded in radio astronomy observations in Orion-IRc2 and the cold prestellar core B1-bS.Comment: Accepted for publication in the Astrophysical Journal Letters 04 June 201

A Rational Expectations Model for Simulation and Policy Evaluation of the Spanish Economy

This paper describes a Rational Expectations Model of the Spanish economy, REMS, which is in the tradition of small open economy dynamic general equilibrium models, with a strongly microfounded system of equations. The model is built on standard elements, but incorporates some distinctive features to provide an accurate description of the Spanish economy. We contribute to the existing models of the Spanish economy by adding search and matching rigidities to a small open economy framework. Our model also incorporates habits in consumption and rule-of-thumb households. As Spain is a member of EMU, we model the interaction between a small open economy and monetary policy in a monetary union. The model is primarily constructed to serve as a simulation tool at the Spanish Ministry of Economic Affairs and Finance. As such, it provides a great deal of information regarding the transmission of policy shocks to economic outcomes. The paper describes the structure of the model in detail, as well as the estimation and calibration technique and some examples of simulations.general equilibrium, rigidities, policy simulations

The REMSDB Macroeconomic Database of The Spanish Economy

This paper presents a new macroeconomic database for the Spanish economy, REMSDB. The construction of this database has been oriented to conducting medium-term simulations for policy evaluation with the REMS model, a large Rational Expectations macroeconomic Model for Spain. The paper provides a detailed description of the data and documents its main statistical properties. The database is thought to be of major interest to related applications,whether strictly associated with the REMS model or, rather, with empirical macroeconomic studies.Spanish Data, Growth Data, Business Cycle Data, REMS

Culture and World Vision: The Cognitive Mythical Mode

Abstract Culture is the system of knowledge, from whose meanings the human being screened and selected their understanding of Reality in the broad sense, and interprets and regulates the facts and data of social behavior. In this sense, culture is a program for social action and acting in humans during the process of socialization and social interaction. The meanings of each culture are the cumulative product of collective and individual thinking, in ecological economic, social and political specific situations, so are the expression of each particular cultural historical conjuncture. Moreover, the universal cognitive structure for the apprehension of cultural reality is the World Vision (WV). Due to its importance and significance as substratum of religious and political belief systems, we will gird our study to mythical cognitive mode or mythical WV. Keywords: beliefs, culture, modal logic, myth, mythical dimension, mythopoiesis, world vision Cite This Article: J. Nescolarde-Selva, and J.L. Usó-Doménech, "Culture and World Vision: The Cognitive Mythical Mod

Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactorsand 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 (<1E-03 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.Comment: Accepted for publication in Astronomy and Astrophysics in September 21, 2017. 16 pages, 18 figure

Another beauty of analytical chemistry: chemical analysis of inorganic pigments of art and archaeological objects

[EN] This lecture text shows what fascinating tasks analytical chemists face in Art Conservation and Archaeology, and it is hoped that students reading it will realize that passions for science, arts or history are by no means mutually exclusive. This study describes the main analytical techniques used since the eighteenth century, and in particular, the instrumental techniques developed throughout the last century for analyzing pigments and inorganic materials, in general, which are found in cultural artefacts, such as artworks and archaeological remains. The lecture starts with a historical review on the use of analytical methods for the analysis of pigments from archaeological and art objects. Three different periods can be distinguished in the history of the application of the Analytical Chemistry in Archaeometrical and Art Conservation studies: (a) the "Formation'' period (eighteenth century1930), (b) the "Maturing'' period (1930-1970), and (c) the "Expansion'' period (1970-nowadays). A classification of analytical methods specifically established in the fields of Archaeometry and Conservation Science is also provided. After this, some sections are devoted to the description of a number of analytical techniques, which are most commonly used in routine analysis of pigments from cultural heritage. Each instrumental section gives the fundamentals of the instrumental technique, together with relevant analytical data and examples of applications.Financial support is gratefully acknowledged from Spanish ‘‘I+D+I MINECO’’ projects CTQ2011-28079-CO3-01 and CTQ2014-53736-C3-1-P supported by ERDEF funds.Domenech Carbo, MT.; Osete Cortina, L. (2016). 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Rev Conserv 4:39–51Montero Ruiz I, Garcia Heras M, López-Romero E (2007) Arqueometría: cambios y tendencias actuales. Trabajos de Prehistoria 64:23–40Fernandes Vieira G, Sias Coelho LJ (2011) Arqueometría: Mirada histórica de una ciencia en desarrollo. Revista CPC 13:107–133Rees-Jones SG (1990) Early experiments in pigment analysis. Stud Conserv 35:93–101Allen RO (1989) The role of the chemists in archaeological studies. In: Allen RO (ed) Archaeological chemistry IV. Advances in chemistry. American Chemical Society, Washington DC, pp 1–17Plesters J (1956) Cross-sections and chemical analysis of paint samples. Stud Conserv 2:110–157 and references thereinGilberg M (1987) Friedrich Rathgen: the father of modern archaeological conservation. J Am Inst Conserv 26:105–120Olin JS, Salmon ME, Olin CH (1969) Investigations of historical objects utilizing spectroscopy and other optical methods. Appl Optics 8:29–39Feller RL (1954) Dammar and mastic infrared analysis. 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In: Proceedings of the International School of Physics “Enrico Fermi”. IOS Press, Amsterdam, pp 407–432Doménech-Carbó A, Doménech-Carbó MT, Valle-Algarra FM, Domine ME, Osete-Cortina L (2013) On the dehydroindigo contribution to Maya Blue. J Mat Sci 48:7171–7183Lovric M, Scholz F (1997) A model for the propagation of a redox reaction through microcrystals. J Solid State Electrochem 1:108–113Fitzgerald AG, Storey BE, Fabian D (1993) Quantitative microbeam analysis. Scottish Universities Sumer School in Physics and Institute of Physics Publishing, BristolDoménech-Carbó A (2015) Dating: an analytical task. ChemTexts 1:5Mairinger F, Schreiner M (1982) New methods of chemical analysis-a tool for the conservator. Science and Technology in the service of conservation, IIC, London, pp 5–13Malissa H, Benedetti-Pichler AA (1958) Anorganische qualitative Mikroanalyse. Springer, New YorkTertian R, Claisse F (1982) Principles of quantitative X-ray fluorescence analysis. 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Springer, BerlinGoldstein JI, Newbury DE, Echlin P, Joy DC, Lyman CE, Echlin P, Lifshin E, Sawyer L, Michael JR (2003) Scanning electron microscopy and X-ray microanalysis. Plenum Press, New YorkDoménech-Carbó A, Doménech-Carbó MT, Más-Barberá X (2007) Identification of lead pigments in nanosamples from ancient paintings and polychromed sculptures using voltammetry of nanoparticles/atomic force microscopy. Talanta 71:1569–1579Reedy TJ, Reedy ChL (1988) Statistical analysis in art conservation research. The Getty Conservation Institute, Los AngelesEastaugh N, Walsh V, Chaplin T, Siddall R (2004) Pigment compendium, optical microscopy of historical pigments. Elsevier, OxfordFeller RL, Bayard M (1986) Terminology and procedures used in the systematic examination of pigment particles with polarizing microscope. In: Feller RL (ed) Artists’ pigment. A handbook of their history and characteristics, vol 1. National Gallery of Art, Washington, pp 285–298Feller RL (ed) (1986) Artists’ pigment. 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National Gallery of Art, Washington, pp 65–108Domenech-Carbó MT, de Agredos Vazquez, Pascual ML, Osete-Cortina L, Domenech A, Guasch-Ferré N, Manzanilla LR, Vidal C (2012) Characterization of Pre-hispanic cosmetics found in a burial of the ancient city of Teotihuacan (Mexico). J Archaeol Sci 39:1043–1062Mühlethaler B, Thissen J (1993) Smalt. In: Roy A (ed) Artists’ pigments. A handbook of their history and characteristics, vol 2. National Gallery of Art, Washington, pp 113–130Musumarra G, Fichera M (1998) Chemometrics and cultural heritage. Chemometr Intell Lab Syst 44:363–372Hochleitner B, Schreiner M, Drakopoulos M, Snigireva I, Snigirev A (2005) Analysis of paint layers by light microscopy, scanning electron microscopy and synchrotron induced X-ray micro-diffraction. In: Van Grieken R, Janssens K (eds) Cultural heritage conservation and environment impact assessment by non-destructive testing and micro-analysis. AA Balkema Publishers, London, pp 171–182Švarcová S, Kočí E, Bezdička P, Hradil D, Hradilová J (2010) Evaluation of laboratory powder X-ray micro-diffraction for applications in the fields of cultural heritage and forensic science. Anal Bioanal Chem 398:1061–1076Van de Voorde L, Vekemans B, Verhaeven E, Tack P, DeWolf R, Garrevoet J, Vandenabeele P, Vincze L (2015) Analytical characterization of a new mobile X-ray fluorescence and X-ray diffraction instrument combined with a pigment identification case study. Spectrochim Acta B 110:14–19Hochleitner B, Desnica V, Mantler M, Schreiner M (2003) Historical pigments: a collection analyzed with X-ray diffraction analysis and X-ray fluorescence analysis in order to create a database. Spectrochim Acta B 58:641–649Middleton PS, Ospitali F, Di Lonardo F (2005) Case study: painters and decorators: Raman spectroscopic studies of five Romano-British villas and the Domus Coiedii at Suasa, Italy. 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Clay Miner 36:403–419Doménech-Carbó A, Doménech-Carbó MT, López-López F, Valle-Algarra FM, Osete-Cortina L, Arcos-Von Haartman E (2013) Electrochemical characterization of egyptian blue pigment in wall paintings using the voltammetry of microparticles methodology. Electroanalysis 25:2621–2630Doménech-Carbó MT, Edwards HGM, Doménech-Carbó A, del Hoyo-Meléndez JM, de la Cruz-Cañizares J (2012) An authentication case study: Antonio Palomino vs. Vicente Guillo paintings in the vaulted ceiling of the Sant Joan del Mercat church (Valencia, Spain). J Raman Spectrosc 43:1250–1259Lovric M, Scholz F (1999) A model for the coupled transport of ions and electrons in redox conductive microcrystals. J Solid State Electrochem 3:172–175Oldham KB (1998) Voltammetry at a three phase junction. J Solid State Electrochem 2:367–377Doménech A, Doménech-Carbó MT, Gimeno-Adelantado JV, Bosch-Reig F, Saurí-Peris MC, Sánchez-Ramos S (2001) Electrochemical identification of iron oxide pigments (earths) from pictorial microsamples attached to graphite/polyester composite electrodes. Analyst 126:1764–1772Doménech A, Doménech-Carbó MT, Moya-Moreno MCM, Gimeno-Adelantado JV, Bosch-Reig F (2000) Identification of inorganic pigments from paintings and polychromed sculptures immobilized into polymer film electrodes by stripping differential pulse voltammetry. Anal Chim Acta 407:275–289Doménech-Carbó A, Doménech-Carbó MT, Valle-Algarra FM, Gimeno-Adelantado JV, Osete-Cortina L, Bosch-Reig F (2016) On-line database of voltammetric data of immobilized particles for identifying pigments and minerals in archaeometry, conservation and restoration (ELCHER database). 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First detection of the pre-biotic molecule glycolonitrile (HOCH2CN) in the interstellar medium

Theories of a pre-RNA world suggest that glycolonitrile (HOCH$_2$CN) is a key species in the process of ribonucleotide assembly, which is considered as a molecular precursor of nucleic acids. In this Letter, we report the first detection of this pre-biotic molecule in the interstellar medium (ISM) by using ALMA data obtained at frequencies between 86.5$\,$GHz and 266.5$\,$GHz toward the Solar-type protostar IRAS16293-2422 B. A total of 15 unblended transitions of HOCH$_2$CN were identified. Our analysis indicates the presence of a cold (T$\rm _{ex}$=24$\pm$8$\,$K) and a warm (T$\rm _{ex}$=158$\pm$38$\,$K) component meaning that this molecule is present in both the inner hot corino and the outer cold envelope of IRAS16293 B. The relative abundance with respect to H$_2$ is (6.5$\pm$0.6)$\times$10$^{-11}$ and $\geq$(6$\pm$2)$\times$10$^{-10}$ for the warm and cold components respectively. Our chemical modelling seems to underproduce the observed abundance for both the warm and cold component under various values of the cosmic-ray ionisation rate ($\zeta$). Key gas phase routes for the formation of this molecule might be missing in our chemical network.Comment: 5 pages, 4 figures, 2 tables, accepted in Monthly Notices of the Royal Astronomical Society Letter

FIB-FESEM and EMPA results on Antoninianus silver coins for manufacturing and corrosion processes

[EN] A set of ancient Antoninianus silver coins, dating back between 249 and 274¿A.D. and minted in Rome, Galliae, Orient and Ticinum, have been characterized. We use, for the first time, a combination of nano-invasive (focused ion beam-field emission scanning electron microscopy-X-ray microanalysis (FIB-FESEM-EDX), voltammetry of microparticles (VIMP)) and destructive techniques (scanning electron microscopy (SEM-EDX) and electron microprobe analysis (EMPA)) along with non-invasive, i.e., micro-Raman spectroscopy. The results revealed that, contrary to the extended belief, a complex Ag-Cu-Pb-Sn alloy was used. The use of alloys was common in the flourishing years of the Roman Empire. In the prosperous periods, Romans produced Ag-Cu alloys with relatively high silver content for the manufacture of both the external layers and inner nucleus of coins. This study also revealed that, although surface silvering processes were applied in different periods of crisis under the reign of Antoninii, even during crisis, Romans produced Antoninianus of high quality. Moreover, a first attempt to improve the silvering procedure using Hg-Ag amalgam has been identified.Financial support was provided by Sapienza University of Rome (Ateneo funding, 2014 15) and Spanish projects CTQ2014-53736-C3-1-P and CTQ2014-53736-C3-2-P, which are supported with Ministerio de Economía, Industria y Competitividad (MINECO) and Fondo Europeo de Desarrollo Regional (ERDF) funds, as well as project CTQ2017-85317-C2-1-P supported with funds from, MINECO, ERDF and Agencia Estatal de Investigación (AEI). PhD grants of the Department of Earth Sciences, Sapienza University of Rome, are gratefully acknowledgedDomenech Carbo, MT.; Di Turo, F.; Montoya, N.; Catalli, F.; Doménech Carbó, A.; De Vito, C. (2018). FIB-FESEM and EMPA results on Antoninianus silver coins for manufacturing and corrosion processes. Scientific Reports. 8. https://doi.org/10.1038/s41598-018-28990-xS8Doménech-Carbó, A., del Hoyo-Meléndez, J. M., Doménech-Carbó, M. T. & Piquero-Cilla, J. Electrochemical analysis of the first Polish coins using voltammetry of immobilized particles. Microchem. J. 130, 47–55 (2017).Di Turo, F. et al. Archaeometric analysis of Roman bronze coins from the Magna Mater temple using solid-state voltammetry and electrochemical impedance spectroscopy. Anal. Chim. Acta 955, 36–47 (2017).Doménech-Carbó, A., Doménech-Carbó, M. T. & Peiró-Ronda, M. A. Dating Archeological Lead Artifacts from Measurement of the Corrosion Content Using the Voltammetry of Microparticles. Anal. Chem. 83, 5639–5644 (2011).Giumlia-Mair, A. et al. Surface characterisation techniques in the study and conservation of art and archaeological artefacts: a review. 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Spectrally-resolved UV photodesorption of CH4 in pure and layered ices

Context. Methane is among the main components of the ice mantles of insterstellar dust grains, where it is at the start of a rich solid-phase chemical network. Quantification of the photon-induced desorption yield of these frozen molecules and understanding of the underlying processes is necessary to accurately model the observations and the chemical evolution of various regions of the interstellar medium. Aims. This study aims at experimentally determining absolute photodesorption yields for the CH4 molecule as a function of photon energy. The influence of the ice composition is also investigated. By studying the methane desorption from layered CH4:CO ice, indirect desorption processes triggered by the excitation of the CO molecules is monitored and quantified. Methods. Tunable monochromatic VUV light from the DESIRS beamline of the SOLEIL synchrotron is used in the 7 - 13.6 eV (177 - 91 nm) range to irradiate pure CH4 or layers of CH4 deposited on top of CO ice samples. The release of species in the gas phase is monitored by quadrupole mass spectrometry and absolute photodesorption yields of intact CH4 are deduced. Results. CH4 photodesorbs for photon energies higher than ~9.1 eV (~136 nm). The photodesorption spectrum follows the absorption spectrum of CH4, which confirms a desorption mechanism mediated by electronic transitions in the ice. When it is deposited on top of CO, CH4 desorbs between 8 and 9 eV with a pattern characteristic of CO absorption, indicating desorption induced by energy transfer from CO molecules. Conclusions. The photodesorption of CH4 from the pure ice in various interstellar environments is around 2.0 x 10^-3 molecules per incident photon. Results on CO-induced indirect desorption of CH4 provide useful insights for the generalization of this process to other molecules co-existing with CO in ice mantles