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Colaço, Marcos V.; Sena, Gabriela; Fidalgo, Gabriel and others, E-mail: mvcolaco@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] Microtomography using synchrotron sources has become a useful tool in biological imaging research since synchrotron radiation properties enable SR-μCT to reconstruct highly resolved 3D image. Several applications using SR- μCT have been made by our group (some are still in progress) at IMX beamline-LNLS, among which we can highlight applications in insects, tadpoles and fishes. Among the most recent paper, we can highlight the use of SR-μCT to study the tadpoles, describing external and internal morphological features like cartilage, muscles, sacs containing calcium, crystalline and skin at a range of developmental stages. Another recent works deal with the insect Rhodnius prolixus , the most important vector of Chagas’ disease. In the first work we investigated the effects of treatments with triflumuron in the ecdysis period (the molting of the R. prolixus cuticle). Images of this insect in such conditions have never been presented before. The other work tested different staining methods in order to find the best protocol to study the nervous system of R. prolixus. Both works used IMX beamline-LNLS with pink beam and resolution of 1.9 μm. Other project is underway using SR-μCT: study of the internal anatomy of the small fishes, especially regarding the structures related to feeding and reproductive systems. With the new 4th generation light source (SIRIUS) we expect a wide range of new possibilities, allowing for much more sensitive analyses, grounding the collaborations between physics, biology, environmental and materials sciences. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 120; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Bastos, Isadora T. de S., E-mail: isadoratairinne@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
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[en] Studies leading to a greater comprehension of biologically active compounds in the solid state play a key role in the synthesis of new drugs. As important as the design and synthesis of new drugs is their structural characterization; exploring the arrangements of molecules in crystals provides a path to the design of new compounds and to the elucidation of processes in which a molecule recognizes a particular biological target. In this work, we determined the crystal structure of LASSBio-1366 with X-ray powder diffraction (XRPD) data. This compound was planned and synthesized in the Laboratory of Evaluation and Synthesis of Bioactive Substances – LASSBio® of the Federal University do Rio de Janeiro (UFRJ) as part of a research program to develop a series of compounds with anti-inflammatory properties. LASSBio-1366 is a N-methyl-N-acylhydrazonic derivative inhibitor of PDE4 and TNF-α in vitro and also active in LPS-induced inflammation models in vivo, thus it can be highlighted as anti-inflammatory prototype compound inhibitor of PDE4. The XRPD were recorded at room temperature on a STADI-P powder diffractometer (Stoe®, Darmstadt, Germany) and the crystal structure determination procedure of the LASSBio-1366 was performed both by indexing and decomposing the powder pattern using the Topas Academic v.5.0 software program via a Pawley fit and the space group was determined as being Pbca. The cell volume found in the indexing procedure suggested eight molecules per unit cell (Z = 8) and one molecule in the asymmetric unit (Z´ = 1). Subsequently, the Rietveld refinement of the final crystal structure was conducted using the Topas Academic v.5.0 software program. The Rietveld method was used to refine the crystal structure and the goodness-of-fit indicator as well as R-factors were χ2 = 1.516, RBragg = 1.974%, Rwp = 2.475% and Rexp= 1.632%. The crystal structure of LASSBio-1366 allowed us to show structural aspects of the composite solid phase allowing the characterization of the relative configuration E of the imine double bond. Our goal is to continue performing the structural characterization of polycrystalline compounds and for this we can use Paineira beamline on Sirius at the Brazilian Synchrotron Light Laboratory. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 104; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Lima, Thiago A.R.M.; Valerio, Mário E. G.; Ilavsky, Jan, E-mail: thiago.remacre@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] Calcium phosphate scaffolds with a hierarchical porous architecture were prepared by a new dualtemplate (corn starch and cetyltrimethylammonium bromide (CTAB) surfactant) used to cast the calcium phosphate nanoparticles and development scaffolds with size hierarchical porous distribution. The powder X-ray diffraction (XRD) results showed that only the HAP crystalline phase is present in the samples after calcination; the Scanning Electron Microscopy (SEM) combined with Small Angle (SAXS) and Ultra-Small Angle X-ray Scattering (USAXS) techniques showed that the porous arrangement is promoted by needle-like nanoparticles, and that the pore size distributions depend on the drip-order of the calcium and the phosphate solutions during the template preparation stage. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 122; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Menezes, Luana C.W. de; Pacheco, Kaike R.M.; Bassi, Maiara de J.; Oliveira, Camilla K.B.Q.M. de; Roman, Lucimara S.; Holakoei, Soheila; Rocco, Maria L.M.; Queiroz, Rodrigo V.; Bagnis, Diego, E-mail: soheila.holakoei@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] The strategy of using semiconductor materials with different properties as electron donor materials in organic solar cells (OSC) is used to improve absorption, stability or charge generation. In this work, it is investigated the effect of a silafluorene derivative copolymer, the poly[2,7-(9,9-dioctyldibenzosilole)-alt-4,7-bis(thiophene-2-yl)benzo-2,1,3-thiadiazole] (PSiF-DBT), sensitized by a low-cost homopolymer from PPV (polyparaphenylene vinylene) family, the poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV). The interaction between the two donor (neat and in a blend) polymers films was evaluated by ultraviolet-visible, photoluminescence, X-ray photoabsorption (NEXAFS) spectroscopies, atomic force microscopy (AFM) and correlated to the observed in photovoltaic performance. We studied the mixture as active layer in two device’s geometries - considering bi-layer devices with a fullerene derivative and inverted flexible devices blade coated in air conditions with a non-fullerene small molecule acceptor. Also, resonant Auger spectroscopy using the core-hole clock (CHC) method was employed in order to evaluate the ultrafast charge delocalization times of conjugated polymers in the low-femtosecond regime. The results show that the homopolymer can improve the absorption spectra and the nonradiative-energy transfer from it to silafluorene derivative copolymer acts as a photosensitizer in the copolymer units. In addition, the blend film exhibits an organized morphology resulting in better absorption stability than the neat films when kept under continuous illumination. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 46; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Sabadini, Julia B.; Loh, Watson, E-mail: j230055@dac.unicamp.br
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] The literature describes many studies on complex systems formed by the interaction of oppositele-charged species in solution, which undergo coacervation. These coacervates may be formed by the combination of two polyelectrolytes with different charges, or polyelectrolytes and ionic surfactants, as well as involving block-copolymers, consisting of hydrophilic and ionic parts with charged species with opposite charges. However, it is still unclear whether or in which conditions these structures represent equilibrium systems. In other words, situations in which morphology, phase size, composition, etc., of the structures are no longer dependent on the preparation procedure and aging. This is the central point that is investigated in this project. For this, coacervates consisting of copolymers containing a hydrophilic neutral block and another anionic, such as polyacrylamide-b-poly(acrylic acid), (PAmx-b-PAAy) and poly(ethylene oxide)-b-poly(acrylic acid), (PEOx-b-PAAy), which are neutralized by the polycation poly(diallyldimethylammonium chloride), PDADMAC of different molar masses. To achieve these objectives, the systems were prepared in different concentration of the components, by using different protocols. Based on the recent results, it is still inconclusive whether or not the complexes are in an equilibrium state. Concerning the structure of the complexes (concentrated systems), they were characterized by using, light scattering measurements (DLS and SLS) and low-angle X-ray scattering (SAXS). From SAXS results, it was verified small signs of crystalline structure that is formed in two length scales, in the more concentrated mixtures of these complexes. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 49; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Paiva, Katrine; Colaço, Marcos V.; Fidalgo, Gabriel and others, E-mail: katrine.ps@gmail.com, E-mail: mvcolaco@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] Micro-CT has been used as an important tool in biological research, in particular for amphibians, due to its is non-invasive method allowing to carry out more accurate studies on the morphology of frogs, such as skeleton, muscle, ocular structure and leaves the specimen intact. A peculiar species of tadpole called Thoropa miliaris, found along the Brazilian Atlantic Rain Forest, reproduces under extreme environmental conditions and lives in water films that run along rock outcrops along the forest, near or isolated from river and rivulets. In early stages post-hatching of the egg, T. miliaris tadpole presents deposits of calcium carbonate crystals in their lymphatic glands, known as endolymphatic calcium deposits (ECD), which are composed of aragonite and likely represent an important source of calcium for bone formation during and after metamorphosis. T. miliaris tadpoles were scanned in the X-ray microtomography beamline (IMX) at Brazilian Synchrotron Light Laboratory (LNLS) to obtaining a detailed anatomical description of soft tissue. Images were acquired with 5x or 2x magnification lenses, which give a virtual pixel size of 4.11 μm and 1.64 μm. Depending of sample size we used 1000 projections over 180° or 2000 projections over 360°. The distance sample-to-detector was 20 cm to increase phase contrast effect. Tomographic images were obtained with and without silicon filter depending on the type of sample (different stages of development, ECD or extracted bones) and the exposure time that it was submitted to optimize image quality. Specimen of T. miliaris has tissues whose densities are similar and IMX beamline afforded to obtain tomographic images, improving excellent edge definition between regions of different tissues. Furthermore, by means of X-ray diffraction (XRD1 beamline, with energy of 12 keV) we evaluated different stages (from 25 to 46) of the specimen T. miliaris in order to verify the mineral composition of the remaining samples, such as crystal structure of the ECD and bones. The new Brazilian synchrotron light source, Sirius, will allow us to carry out quantitative and qualitative analyzes with higher quality and fast acquisition time for biological interest (i.e., morphology, ontology, heterochrony), as well as development of new methodologies for biological samples. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 81; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Pickler, Arissa; Mendes, G.; Tanure, T.; Serqueira, L.; Ferreira-Machado, S.C.; Almeida, C.E. de; Barroso, R.C.; Salata, C., E-mail: arissapickler@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] Breast cancer (BC) survival is increased by the diagnosis of earlier-stage disease and treatments improve, however, the side effects of cancer treatments, such as cardiotoxicity, remain clinically important. Radiotherapy for breast cancer often involves some incidental exposure of the heart to ionizing radiation. Women with breast cancer who are treated with adjuvant radiation have a decreased risk of local recurrence but an increased risk of mortality from coronary artery disease (CAD). The possible reason to occurrence of CAD after radiotherapy is the unfavourable remodelling of the coronary artery due the radiation injury. Although the effects of cardiotoxicity induced by BC treatment are well known, its precise mechanisms are not completely elucidated. Losartan is an angiotensin II type 1 receptor (AT1) antagonist widely used for the treatment of hypertension as well as other cardiovascular diseases. Previous studies showed the efficacy of losartan to correct the altered structure and endothelial dysfunction of resistance arteries from patients with essential hypertension, and also prevent the progression of coronary atherosclerosis in patients with significant atherosclerotic disease. The present study aims to clarify how the radiotherapy for breast cancer affects the coronary artery and to determine if losartan can be used to minimize the side effects of the irradiation in this artery. Determination of the distribution and chemical state of elemental constituents within biological systems at sub-cellular level down to trace level concentrations is of growing importance for gaining new insights about the highly complex functions of elements within the tissue or cells. CARNAÚBA (Coherent X-Ray Nanoprobe Beamline) is the tender-to-hard X-ray nanoprobe under construction at the new Brazilian synchrotron light source SIRIUS. The beamline provides two separated experimental stations, one with sub-micrometer resolution and another with nanometer resolution, to cover various analysis techniques, including X-ray fluorescence (XRF). The all achromatic CARNAÚBA optics will covers continuously the energy range from 2 to 15 keV. With this energy range, it will be possible to analyze K-lines of light elements, like phosphorus and sulfur, and also heavier elements, like calcium and zinc. The use of CARNAÚBA beamline will provide both submicrometer spatial resolution and elemental mapping of important elements in coronary artery of hypertensive rats allowing analyze the tissue in a cellular level. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 91; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Rodrigues, Lorena A.; Neta, Augusta C.I.; Figueiredo, Roberto B.; Souza, Angelo M. de, E-mail: loreaarao@gmail.com
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] Despite all progress in improving desirable properties in metallic materials through alloying, mechanical processing and thermal treatments, knowledge of the interface structure down to nanoscale is crucial for designing materials with new regimes of property-performance space. The interface structure of polycrystalline metallic materials (such as grain boundaries, subgrain boundaries, twin and twist transition boundaries) can strongly influence their properties. Despite the large body of work, there are still important questions on interfaces of metallic systems that remain unanswered, particularly regarding their atomic arrangements. These arrangements have been mainly characterized by imaging techniques such as scanning and transmission electron microscopy (SEM/TEM), which can access structural data locally, but are destructive and statistically limited. Methods that rely on large-area results which are statistically relevant, such as X-ray diffraction (XRD), may lack of a direct interpretation or depend of specific modeling. Recently, the continuous development of third generation synchrotron sources and diffractometer systems with broad-range detectors has opened the possibility of analyzing extremely weak X-ray reflections through the acquisition of a complete diffractogram with excellent reciprocal space resolution and very large count rate, offering higher accuracy and signal-to-noise ratios. In this work, a Mythen 24K detector covering up 120° of scattering angle was used to accumulate counts from synchrotron XRD experiments on commercially pure Mg samples. An acquisition time of 1 h allowed the retrieval of preferential interface structure configurations through the observation of very weak diffraction peaks. Additional peaks were located close to the Mg (102), (200), (204) and (300) fundamental reflections. A kinematical simulation scanning possible interface structures was performed to establish the correspondence of non-bulk peaks with the interfacial structural organization of atoms which may be responsible for such scatterings. The simulated interfaces were probed for a wide range of angular displacements with respect to the main cleavage planes of the bulk system; as the angles and inclusion interfaces are varied, we are able to retrieve the configurations that produce diffraction peaks with appreciable intensity at positions that were compatible with the additional peaks observed experimentally. The information about the maximum strain at the interface plane (with respect to a pure bulk configuration) and their geometry may be related with conditions that lead to local energy minimization with a symmetry that allows for XRD, representing a long-range ordered pattern of atomic distributions in Mg. The introduced methodology allows for monitoring changes in a system when it undergoes mechanical processes that refine grain sizes and modify grain orientation, for instance. The inherent characteristics of X-rays drives this methodology beyond the microscopy surface analysis, providing at the same time statistical relevance and depth capabilities, thus rendering such approach unique in the field of Materials Science and Engineering. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 96; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Bastos, Raíssa Sodré, E-mail: raissa.bastos@lnls.br
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] X-Ray Scattering, Diffraction and Reflectivity studies of liquid interfaces are becoming well established at Synchrotron Light Sources, allowing IN-SITU characterization of atomic and molecular structures with a great impact in many fields, such as electronics, and pharmaceutical/food industries. It also has a great appeal in pure sciences, providing a practical understanding of phase transitions in quasi-2D systems and surfactants behaviors. However, the (horizontal) liquid interfaces present a challenging problem due to the inability of tilting neither the sample surface nor the source, in order to achieve the incident angle variation, required by the techniques. In this scenario, a few specialized instrumentations have been developed to deflect the incoming beam onto the sample surface with high precision. The first designs presented an additional crystal or mirror at the end of the optics setup, used to tilt the primary beam onto the sample surface. In the former case, the beam moves both vertically and horizontally at the sample when varying the incidence angle, which requires the sample and detector to track the moving X-ray, bringing mechanical instability to the surface. In the mirror case, although the experiment is much more stable, the setup does not allow a reflectivity experiment. A deflecting mirror system is currently available for use at the XRD2 beamline at UVX. In this work, we present the design and development of an alternative deflecting system, in which the liquid surface stays stationary over the whole angular variation. The system, called by ''deflector'', uses two crystals in a DCM configuration, each one in a different Bragg condition (e.g. Ge 111 and Ge 220 reflections). The sequential Bragg reflections, combined with the rotation of the deflector along the primary beam axis, allows the incident angle at the surface to be changed, while the measuring position remains centered and stationary at the sample surface. Similar designs were implemented on beamlines ID10 and ID15 at ESRF, P08 at PETRA III and I07 at DIAMOND. This is a new design that accounts for the particular requirements of the XRD2 at UVX and future SAGUI beamline at Sirius. The greatest advantage of this system is that it is designed to perfectly fit the existing 6+2 circle diffractometer of the XRD2/SAGUI beamlines, in a way that it can conveniently be used for Grazing Incidence X-ray Diffraction (GIXD) and Grazing Incidence Small Angle X-ray Scattering (GISAXS) in combination with the XRR measurements. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 39; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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Ribeiro, Fabio de A., E-mail: fabio.ribeiro@ifrj.edu.br
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
Proceedings of the 29. RAU: annual users meeting LNLS/CNPEM. Abstract book2019
AbstractAbstract
[en] Nitriles represent a quite abundant class of molecules in a variety of astrophysical environments. Acetonitrile (CH3CN), propionitrile (C2H5CN) and acrylonitrile (C2H3CN) are common examples of saturated and unsaturated organic nitriles present in dark clouds and star-forming regions, while isobutyronitrile (i-C3H7CN) was the first branched molecule to be detected in the interstellar medium (ISM). Noteworthy, CH3CN is a known cometary molecule, and it has been recently detected towards the V4046 Sgr, MWC 480, and HD 163296 protoplanetary disks, what points to the link between the interstellar and nascent planetary systems. However, the reaction routes for producing and destroying such complex molecules are not understood. At temperatures as low as 10 K, gas-phase molecules are expected to condense on dust particles, forming ice mantles. In the case of protoplanetary disks, these ices are exposed to the stellar radiation field from hot young stars, mainly in the far ultraviolet and soft X-ray energy range, what triggers the energetic processing of condensed molecules. In order to estimate the photostability of condensed organic nitriles, we derived the cross-sections for destruction of the parent molecules under conditions that mimic those found in the ISM. The experiments were performed at the SGM beamline at the Brazilian synchrotron laboratory (LNLS). The ices were grown in the multilayer regime, IN-SITU, onto a gold foil substrate cooled at 15 K. Each of these ices was exposed to different doses of zero order synchrotron radiation, and the damage induced after each irradiation was probed by the Near Edge X-ray Absorption Fine Structure (NEXAFS) technique at the N K-edge in the total electron yield (TEY) detection mode. As a general trend, it was observed the decrease of the N1s → π*(CN) excitation at ~399 eV, and its splitting into three main components, due to the different chemical environment of the irradiated ices. The two new spectral features appeared around ~398 and ~401 eV. This result might indicate the synthesis of imine-based compounds (R–C=C=NH) from nitrile-bearing ices exposed to UV and X-ray radiation, corroborating that the abundance of imines, such as the known interstellar ketenimine (CH2CNH), might be correlated to the abundance of nitriles. Cross-sections for the destruction of the parent molecule were derived from the integrated resonance as a function of the photon exposure. The extrapolation to the typical X-ray photon flux from young stellar objects indicates that nitriles should be processed within the first millions of years of activity of the central protostellar. We hope that these parameters may aid in the developing of chemical evolution models of nitrile rich environments in the ISM. (author)
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Laboratório Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); 134 p; 2019; p. 45; 29. RAU: annual users meeting LNLS/CNPEM; Campinas, SP (Brazil); 5-7 Nov 2019
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