scholarly journals Reviewing in situ analytical techniques used to research Martian geochemistry: From the Viking Project to the MMX future mission

2022 ◽  
pp. 339499
Author(s):  
Jennifer Huidobro ◽  
Julene Aramendia ◽  
Gorka Arana ◽  
Juan Manuel Madariaga
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.


2009 ◽  
Vol 6 (1) ◽  
pp. 491-524 ◽  
Author(s):  
U. Schuster ◽  
A. Hannides ◽  
L. Mintrop ◽  
A. Körtzinger

Abstract. Highly accurate and precise measurements of marine carbon components are required in the study of the marine carbon cycle, particularly when investigating the causes for its variability from seasonal to interannual timescales. This is especially true in the investigation of the consequences of anthropogenic influences. The analysis of any component requires elaborate instrumentation, most of which is currently used onboard ships, either in manual mode or autonomous mode. Technological developments result in more and more instruments that have long-term reliability so that they can be deployed on surface moorings and buoys, whilst the great technological and operational challenges mean that only few sensors have been developed that can be used for sub-surface in situ measurements on floats, robots, or gliders. There is a special need for autonomous instruments and sensors that are able to measure a combination of different components, in order to increase the spatial and temporal coverage of marine carbon data. This paper describes analytical techniques used for the detection of the marine dissolved carbon components, both inorganic and organic: the fugacity of CO2, total dissolved inorganic carbon, pH, alkalinity, and dissolved organic carbon. By pointing out advantages, disadvantages, and challenges of the techniques employed in the analysis of each component, we aim to aid non-carbon marine scientists, sensor developers and technologists, in the decision where to tackle the challenges of further development.


Minerals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1047
Author(s):  
Jill Dill Pasteris ◽  
Yeunook Bae ◽  
Daniel E. Giammar ◽  
Sydney N. Dybing ◽  
Claude H. Yoder ◽  
...  

The identification and characterization of lead-bearing and associated minerals in scales on lead pipes are essential to understanding and predicting the mobilization of lead into drinking water. Despite its long-recognized usefulness in the unambiguous identification of crystalline and amorphous solids, distinguishing between polymorphic phases, and rapid and non-destructive analysis on the micrometer spatial scale, the Raman spectroscopy (RS) technique has been applied only occasionally in the analysis of scales in lead service lines (LSLs). This article illustrates multiple applications of RS not just for the identification of phases, but also compositional and structural characterization of scale materials in harvested lead pipes and experimental pipe-loop/recirculation systems. RS is shown to be a sensitive monitor of these characteristics through analyses on cross-sections of lead pipes, raw interior pipe walls, particulates captured in filters, and scrapings from pipes. RS proves to be especially sensitive to the state of crystallinity of scale phases (important to their solubility) and to the specific chemistry of phases precipitated upon the introduction of orthophosphate to the water system. It can be used effectively alone as well as in conjunction with more standard analytical techniques. By means of fiber-optic probes, RS has potential for in situ, real-time analysis within water-filled pipes.


Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1060
Author(s):  
Hiroshi Hidaka

Isotopic analyses of elements in the natural reactor materials have often been performed to understand the distribution behaviors of the fission products and to evaluate the function of nuclear reactions since the first discovery of a natural reactor in 1972. Several types of unique microminerals, including significant amounts of fission products, have been found in and around the Oklo and the Bangombé natural reactors. In the past two decades, microbeam techniques using ion and laser probe facilities have been effectively applied for the in situ isotopic analyses of individual microminerals to investigate the migration behaviors of fissiogenic radioisotopes produced in the reactors. This paper presents a review of interpretations of the isotopic results of microminerals found in and around the natural reactors.


2018 ◽  
Vol 47 (3) ◽  
pp. 736-851 ◽  
Author(s):  
Alok M. Tripathi ◽  
Wei-Nien Su ◽  
Bing Joe Hwang

Interface is a key to high performance and safe lithium-ion batteries or lithium batteries.


2003 ◽  
Vol 24 (3) ◽  
pp. 12 ◽  
Author(s):  
Duncan Veal ◽  
Philip Bell ◽  
Hayley Brown ◽  
Hung-Yoon Choi ◽  
Peter Karuso

Fluorescence has many advantages over traditional colour and radioactive labels, and is playing an increasingly important role in the most powerful analytical techniques. For example, fluorescence is at the heart of many nucleic acid based diagnostics (e.g. DNA microarray, real time-PCR, fluorescence in situ hybridisation, etc), immunofluorescence assays, defined substrate technologies and differential display proteomics and is gradually replacing or complementing other techniques based on colour or radiolabels.


Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5554
Author(s):  
Francesca Ravera ◽  
Esen Efeoglu ◽  
Hugh J. Byrne

Stem cell technology has attracted considerable attention over recent decades due to its enormous potential in regenerative medicine and disease therapeutics. Studying the underlying mechanisms of stem cell differentiation and tissue generation is critical, and robust methodologies and different technologies are required. Towards establishing improved understanding and optimised triggering and control of differentiation processes, analytical techniques such as flow cytometry, immunohistochemistry, reverse transcription polymerase chain reaction, RNA in situ hybridisation analysis, and fluorescence-activated cell sorting have contributed much. However, progress in the field remains limited because such techniques provide only limited information, as they are only able to address specific, selected aspects of the process, and/or cannot visualise the process at the subcellular level. Additionally, many current analytical techniques involve the disruption of the investigation process (tissue sectioning, immunostaining) and cannot monitor the cellular differentiation process in situ, in real-time. Vibrational spectroscopy, as a label-free, non-invasive and non-destructive analytical technique, appears to be a promising candidate to potentially overcome many of these limitations as it can provide detailed biochemical fingerprint information for analysis of cells, tissues, and body fluids. The technique has been widely used in disease diagnosis and increasingly in stem cell technology. In this work, the efforts regarding the use of vibrational spectroscopy to identify mechanisms of stem cell differentiation at a single cell and tissue level are summarised. Both infrared absorption and Raman spectroscopic investigations are explored, and the relative merits, and future perspectives of the techniques are discussed.


Britannia ◽  
2020 ◽  
Vol 51 ◽  
pp. 175-201
Author(s):  
Louisa Campbell

ABSTRACTNon-destructive analytical techniques are now widely and successfully employed in the fields of materials science and conservation. Portable X-ray fluorescence (pXRF) and portable Raman spectrometry have proven particularly valuable for the rapid in-situ analysis of samples, but their applicability for the analysis of archaeological artefacts for which survival of surface treatments can be negatively impacted by post-depositional processes has been underexplored. Roman relief-sculpted monumental inscriptions from the Antonine Wall, commonly referred to as ‘Distance Slabs’, have offered an excellent opportunity to deploy these non-destructive techniques to determine whether they were originally adorned with pigments and, if so, to identify the colours used. This is a revolutionary approach to identifying colours on ancient sandstone sculpture that transforms our understanding of these unique monuments. Elemental composition analysis by pXRF has confirmed evidence for pigments and this is supported by the Raman results, making it possible to develop and reconstruct a palette of colours that originally brought these monuments to life in vibrant polychrome. The research offers a new methodology for identifying pigments on sandstone sculpture and opens new avenues for investigating other classes of material culture alongside the development of bespoke analytical equipment.


2016 ◽  
Author(s):  
R. H. Rhodes ◽  
X. Faïn ◽  
E. J. Brook ◽  
J. R. McConnell ◽  
O. J. Maselli ◽  
...  

Abstract. Superimposed on the coherent and major atmospheric changes in trace gases revealed by ice core records, local high frequency, non-atmospheric features can now be resolved due to improvement s in resolution and precision of analytical techniques. These are signals that could not have survived the low-pass filter effect that firn diffusion exerts on the atmospheric history and therefore do not result from changes in the composition of the atmosphere at the surface of the ice sheet. Using continuous methane (CH4) records obtained from five polar ice cores, we characterize these non-atmospheric signals and explore their origin. Isolated samples, enriched in CH4 in the Tunu13 (Greenland) record are linked to the presence of melt layers. Melting can enrich the methane concentration due to preferential dissolution of methane relative to nitrogen, but we find that an additional in-situ process is required to generate the full magnitude of these anomalies. Furthermore, in the all ice cores studied there is evidence of reproducible, decimetre-scale CH4 variability. Through a series of tests, we demonstrate that this sign al is an artifact of layered bubble trapping in a heterogeneous-density firn column; we term this phenomenon ‘trapping noise’. The magnitude of CH4 trapping noise increases with atmospheric CH4 growth rate and seasonality of density contrasts, and decreases with accumulation rate. Firn air transport model simulations, accounting for layered bubble trapping, are in agreement with our empirical data. Significant annual periodicity is present in the CH4 variability of two Greenland ice cores, suggesting that layered gas trapping at these sites is controlled by regular, seasonal variations in the physical properties of the firn.


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