scholarly journals ExoFiT trial at the Atacama Desert (Chile): Raman detection of biomarkers by representative prototypes of the ExoMars/Raman Laser Spectrometer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marco Veneranda ◽  
Guillermo Lopez-Reyes ◽  
Jesus Saiz ◽  
Jose Antonio Manrique-Martinez ◽  
Aurelio Sanz-Arranz ◽  
...  

AbstractIn this work, the analytical research performed by the Raman Laser Spectrometer (RLS) team during the ExoFiT trial is presented. During this test, an emulator of the Rosalind Franklin rover was remotely operated at the Atacama Desert in a Mars-like sequence of scientific operations that ended with the collection and the analysis of two drilled cores. The in-situ Raman characterization of the samples was performed through a portable technology demonstrator of RLS (RAD1 system). The results were later complemented in the laboratory using a bench top RLS operation simulator and a X-Ray diffractometer (XRD). By simulating the operational and analytical constraints of the ExoMars mission, the two RLS representative instruments effectively disclosed the mineralogical composition of the drilled cores (k-feldspar, plagioclase, quartz, muscovite and rutile as main components), reaching the detection of minor phases (e.g., additional phyllosilicate and calcite) whose concentration was below the detection limit of XRD. Furthermore, Raman systems detected many organic functional groups (–C≡N, –NH2 and C–(NO2)), suggesting the presence of nitrogen-fixing microorganisms in the samples. The Raman detection of organic material in the subsurface of a Martian analogue site presenting representative environmental conditions (high UV radiation, extreme aridity), supports the idea that the RLS could play a key role in the fulfilment of the ExoMars main mission objective: to search for signs of life on Mars.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marco Veneranda ◽  
Guillermo Lopez-Reyes ◽  
Jesus Saiz ◽  
Jose Antonio Manrique-Martinez ◽  
Aurelio Sanz-Arranz ◽  
...  

An amendment to this paper has been published and can be accessed via a link at the top of the paper.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Marco Veneranda ◽  
Guillermo Lopez-Reyes ◽  
Jose Antonio Manrique-Martinez ◽  
Aurelio Sanz-Arranz ◽  
Emmanuel Lalla ◽  
...  

Abstract This work aims to evaluate whether the multi-point analysis the ExoMars Raman Laser Spectrometer (RLS) will perform on powdered samples could serve to classify ultramafic rocks on Mars. To do so, the RLS ExoMars Simulator was used to study terrestrial analogues of Martian peridotites and pyroxenites by applying the operational constraints of the Raman spectrometer onboard the Rosalind Franklin rover. Besides qualitative analysis, RLS-dedicated calibration curves have been built to estimate the relative content of olivine and pyroxenes in the samples. These semi-quantitative results, combined with a rough estimate of the concentration ratio between clino- and ortho-pyroxene mineral phases, were used to classify the terrestrial analogues. XRD data were finally employed as reference to validate Raman results. As this preliminary work suggests, ultramafic rocks on Mars could be effectively classified through the chemometric analysis of RLS data sets. After optimization, the proposed chemometric tools could be applied to the study of the volcanic geological areas detected at the ExoMars landing site (Oxia Planum), whose mineralogical composition and geological evolution have not been fully understood.


2007 ◽  
Vol 330-332 ◽  
pp. 415-418 ◽  
Author(s):  
Xiao Liang Wang ◽  
Xu Dong Li ◽  
Xiao Min Wang ◽  
Jian Lu ◽  
Hui Chuan Zhao ◽  
...  

Collagen (Col) and chitosan (Chi) are both natural polymers and have received extensive investigation in recent years in the field of tissue engineering, but there are few reports on the introduction of hydroxyapatite (HA) into the Col-Ch system. In this study, based on the miscibility of these two polymers under proper condition, hydroxyapatite (HA) was synthesis in the Col-Chi system by in-situ co-precipitate method to give rise to a novel nanocomposite. The structural characterization of such Col-Ch-HA nano-materials was carried out by using FT-IR, XRD, SEM and TGA analyses with main components and Col-Chi samples used for comparison. It was found that there exist interactions between Col and Chi molecules. The nucleation and growth of inorganic phase occurs in the Col-Chi system and final products are uniform dispersion of nano-sized HA in the Col-Chi network without obvious phase separation. This novel nanocomposite would be a promising material for bone tissue engineering.


2020 ◽  
Author(s):  
Guillermo Lopez-Reyes ◽  
Marco Veneranda ◽  
Jose Antonio Manrique Martinez ◽  
Jesus Saiz Cano ◽  
Jesus Medina García ◽  
...  

<p><span>The ESA/Roscosmos ExoMars mission to Mars is scheduled to be launched in 2020. Seeking to prepare the ExoMars operation team to manage the engineering and scientific challenges arising from the Rosalind Franklin rover soon operating at Oxia Planum, a rover prototype equipped with representative ExoMars navigation and analytical systems was recently used in two mission simulations (ExoFit trials)</span></p><p><span>The first field test was carried out in Tabernas (Spain), a desertic area characterized by the presence of clays, partially altered sedimentary rocks and efflorescence salts. The second ExoFit trial was performed in the Atacama Desert (Chile), in a sandy flat land displaying diorite-boulders, clays patches and evaporites.</span></p><p><span>The Raman Laser Simulator (RLS) team participated in both simulations: portable spectrometers were used to determine the mineralogical composition of subsoil samples collected by the rover-drill and to investigate the possible presence of biomarkers. In-situ analysis were carried out by means of the RAD 1 system (Raman Demonstrator), which is a portable spectrometer that follows the same geometrical concept and spectral characteristics of the RLS flight model (FM).</span></p><p><span>In the case of Tabernas trial, additional analysis were performed using the RLS qualification model (EQM2) which at the moment was the most reliable tool to understand the scientific outcome that could derive from the RLS operating on Mars.</span></p><p><span>Prior to analysis, geological samples were crushed and sieved to replicate the granulometry of the powdered material produced by the ExoMars crusher. After flattening, from 8 to 10 spots were analyzed and Raman data and interpreted.</span></p><p><span>From each site, two cores were drilled and analyzed. On one side, the main mineralogical phases detected in the first Atacama core are quartz and calcium carbonate. In addition to those, the mineralogy of the second core also includes hematite and calcium sulphate.</span></p><p><span>On the other side, RAD 1 spectra gathered from Almeria core-samples confirmed the presence of quartz as main mineralogical phase. However, peaks of medium intensity at 146 and 1086 cm<sup>-1</sup> were also observed, confirming the detection of rutile and calcium carbonate respectively. The same samples were further characterized by means of the RLS-EQM2 system: beside confirming the detection of the abovementioned mineral phases, additional Raman biomarkers-related peaks were also found.</span></p><p><span>Even though deeper Raman analysis of ExoFit samples need to be performed, the preliminary results gathered in-situ suggests that Raman spectroscopy could play a kay role in the fulfillment of the ExoMars mission objectives.</span></p>


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
J. I. Bennetch

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.


Author(s):  
J. Liu ◽  
M. Pan ◽  
G. E. Spinnler

Small metal particles have peculiar chemical and physical properties as compared to bulk materials. They are especially important in catalysis since metal particles are common constituents of supported catalysts. The structural characterization of small particles is of primary importance for the understanding of structure-catalytic activity relationships. The shape and size of metal particles larger than approximately 5 nm in diameter can be determined by several imaging techniques. It is difficult, however, to deduce the shape of smaller metal particles. Coherent electron nanodiffraction (CEND) patterns from nano particles contain information about the particle size, shape, structure and defects etc. As part of an on-going program of STEM characterization of supported catalysts we report some preliminary results of CEND study of Ag nano particles, deposited in situ in a UHV STEM instrument, and compare the experimental results with full dynamical simulations in order to extract information about the shape of Ag nano particles.


Reproduction ◽  
2000 ◽  
pp. 325-335 ◽  
Author(s):  
A Calvo ◽  
LM Pastor ◽  
S Bonet ◽  
E Pinart ◽  
M Ventura

Lectin histochemistry was used to perform in situ characterization of the glycoconjugates present in boar testis and epididymis. Thirteen horseradish peroxidase- or digoxigenin-labelled lectins were used in samples obtained from healthy fertile boars. The acrosomes of the spermatids were stained intensely by lectins with affinity for galactose and N-acetyl-galactosamine residues, these being soybean, peanut and Ricinus communis agglutinins. Sertoli cells were stained selectively by Maackia ammurensis agglutinin. The lamina propria of seminiferous tubules showed the most intense staining with fucose-binding lectins. The Golgi area and the apical part of the principal cells of the epididymis were stained intensely with many lectins and their distribution was similar in the three zones of the epididymis. On the basis of lectin affinity, both testis and epididymis appear to have N- and O-linked glycoconjugates. Spermatozoa from different epididymal regions showed different expression of terminal galactose and N-acetyl-galactosamine. Sialic acid (specifically alpha2,3 neuraminic-5 acid) was probably incorporated into spermatozoa along the extratesticular ducts. These findings indicate that the development and maturation of boar spermatozoa are accompanied by changes in glycoconjugates. As some lectins stain cellular or extracellular compartments specifically, these lectins could be useful markers in histopathological evaluation of diseases of boar testis and epididymis.


2018 ◽  
Author(s):  
Devon Jakob ◽  
Le Wang ◽  
Haomin Wang ◽  
Xiaoji Xu

<p>In situ measurements of the chemical compositions and mechanical properties of kerogen help understand the formation, transformation, and utilization of organic matter in the oil shale at the nanoscale. However, the optical diffraction limit prevents attainment of nanoscale resolution using conventional spectroscopy and microscopy. Here, we utilize peak force infrared (PFIR) microscopy for multimodal characterization of kerogen in oil shale. The PFIR provides correlative infrared imaging, mechanical mapping, and broadband infrared spectroscopy capability with 6 nm spatial resolution. We observed nanoscale heterogeneity in the chemical composition, aromaticity, and maturity of the kerogens from oil shales from Eagle Ford shale play in Texas. The kerogen aromaticity positively correlates with the local mechanical moduli of the surrounding inorganic matrix, manifesting the Le Chatelier’s principle. In situ spectro-mechanical characterization of oil shale will yield valuable insight for geochemical and geomechanical modeling on the origin and transformation of kerogen in the oil shale.</p>


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