analytical techniques
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Gases ◽  
2022 ◽  
Vol 2 (1) ◽  
pp. 1-21
Theodora Noely Tambaria ◽  
Yuichi Sugai ◽  
Ronald Nguele

Enhanced coal bed methane recovery using gas injection can provide increased methane extraction depending on the characteristics of the coal and the gas that is used. Accurate prediction of the extent of gas adsorption by coal are therefore important. Both experimental methods and modeling have been used to assess gas adsorption and its effects, including volumetric and gravimetric techniques, as well as the Ono–Kondo model and other numerical simulations. Thermodynamic parameters may be used to model adsorption on coal surfaces while adsorption isotherms can be used to predict adsorption on coal pores. In addition, density functional theory and grand canonical Monte Carlo methods may be employed. Complementary analytical techniques include Fourier transform infrared, Raman spectroscopy, XR diffraction, and 13C nuclear magnetic resonance spectroscopy. This review summarizes the cutting-edge research concerning the adsorption of CO2, N2, or mixture gas onto coal surfaces and into coal pores based on both experimental studies and simulations.

2022 ◽  
Vol 8 ◽  
Eric Aaron ◽  
Joshua Hawthorne-Madell ◽  
Ken Livingston ◽  
John H. Long

To fully understand the evolution of complex morphologies, analyses cannot stop at selection: It is essential to investigate the roles and interactions of multiple processes that drive evolutionary outcomes. The challenges of undertaking such analyses have affected both evolutionary biologists and evolutionary roboticists, with their common interests in complex morphologies. In this paper, we present analytical techniques from evolutionary biology, selection gradient analysis and morphospace walks, and we demonstrate their applicability to robot morphologies in analyses of three evolutionary mechanisms: randomness (genetic mutation), development (an explicitly implemented genotype-to-phenotype map), and selection. In particular, we applied these analytical techniques to evolved populations of simulated biorobots—embodied robots designed specifically as models of biological systems, for the testing of biological hypotheses—and we present a variety of results, including analyses that do all of the following: illuminate different evolutionary dynamics for different classes of morphological traits; illustrate how the traits targeted by selection can vary based on the likelihood of random genetic mutation; demonstrate that selection on two selected sets of morphological traits only partially explains the variance in fitness in our biorobots; and suggest that biases in developmental processes could partially explain evolutionary dynamics of morphology. When combined, the complementary analytical approaches discussed in this paper can enable insight into evolutionary processes beyond selection and thereby deepen our understanding of the evolution of robotic morphologies.

2022 ◽  
Vol 12 (1) ◽  
Tingting Wang ◽  
Benjamin T. Fuller ◽  
Hongen Jiang ◽  
Wenying Li ◽  
Dong Wei ◽  

AbstractYingpan Man, is one of the most exquisitely preserved mummies found in the Xinjiang Uyghur Autonomous Region of China. Here links between Yingpan Man and the Silk Road are explored through a detailed isotopic and bioarchaeological investigation of his life history. Analytical techniques of carbon, nitrogen, and sulfur stable isotope ratio analysis on hair, teeth, muscle and bones as well as associated animal and plant remains, radiocarbon dating and starch grain analysis of dental calculus are presented to visualize never before seen aspects of Yingpan Man’s life, including: environment, breastfeeding and weaning practices, adolescent and adult diet, disease and nutritional status as well as season of death. Furthermore, in combination with a detailed review of his associated grave goods, this research examines the social status and identity of Yingpan Man, and demonstrates the profound impact and cultural fusion that the Silk Road had upon the peoples of Xinjiang and Eurasia.

2022 ◽  
Vol 12 (1) ◽  
M. González-Cabrera ◽  
K. Wieland ◽  
E. Eitenberger ◽  
A. Bleier ◽  
L. Brunnbauer ◽  

AbstractThis work presents a multisensor hyperspectral approach for the characterization of ultramarine blue, a valuable historical pigment, at the microscopic scale combining the information of four analytical techniques at the elemental and molecular levels. The hyperspectral images collected were combined in a single hypercube, where the pixels of the various spectral components are aligned on top of each other. Selected spectral descriptors have been defined to reduce data dimensionality before applying unsupervised chemometric data analysis approaches. Lazurite, responsible for the blue color of the pigment, was detected as the major mineral phase present in synthetic and good quality pigments. Impurities like pyrite were detected in lower quality samples, although the clear identification of other mineral phases with silicate basis was more difficult. There is no correlation between the spatial distribution of the bands arising in the Raman spectra of natural samples in the region 1200–1850 cm−1 and any of the transition metals or rare earth elements (REE). With this information, the previous hypothesis (based on bulk analysis) attributing these bands to luminescence emissions due to impurities of these elements must be revised. We propose the consideration of CO2 molecules trapped in the cages of the aluminosilicate structure of sodalite-type. Additionally, correlation between certain Raman features and the combined presence of Ca, P, and REE, in particular Nd, was detected for the lowest quality pigment. Our results highlight the usefulness of fusing chemical images obtained via different imaging techniques to obtain relevant information on chemical structure and properties.

2022 ◽  
Vol 2 ◽  
William B. Brinckerhoff ◽  
Peter A. Willis ◽  
Antonio J. Ricco ◽  
Desmond A. Kaplan ◽  
Ryan M. Danell ◽  

The Europan Molecular Indicators of Life Investigation (EMILI) is an instrument concept being developed for the Europa Lander mission currently under study. EMILI will meet and exceed the scientific and technical/resource requirements of the organic composition analyzer identified as a core instrument on the Lander. EMILI tightly couples two complementary analytical techniques, based on 1) liquid extraction and processing with capillary electrophoresis and 2) thermal and chemical extraction with gas chromatography, to robustly detect, structurally characterize, and quantify the broadest range of organics and other Europan chemicals over widely-varying concentrations. Dual processing and analysis paths enable EMILI to perform a thorough characterization of potential molecular biosignatures and contextual compounds in collected surface samples. Here we present a summary of the requirements, design, and development status of EMILI with projected scientific opportunities on the Europa Lander as well as on other potential life detection missions seeking potential molecular biosignatures in situ.

Insects ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 83
Marek Golian ◽  
Tanja Bien ◽  
Sebastian Schmelzle ◽  
Margy Alejandra Esparza-Mora ◽  
Dino Peter McMahon ◽  

Most of our knowledge on insect cuticular hydrocarbons (CHCs) stems from analytical techniques based on gas-chromatography coupled with mass spectrometry (GC-MS). However, this method has its limits under standard conditions, particularly in detecting compounds beyond a chain length of around C40. Here, we compare the CHC chain length range detectable by GC-MS with the range assessed by silver-assisted laser desorption/ionization mass spectrometry (Ag-LDI-MS), a novel and rarely applied technique on insect CHCs, in seven species of the order Blattodea. For all tested species, we unveiled a considerable range of very long-chain CHCs up to C58, which are not detectable by standard GC-MS technology. This indicates that general studies on insect CHCs may frequently miss compounds in this range, and we encourage future studies to implement analytical techniques extending the conventionally accessed chain length range. Furthermore, we incorporate 3D scanned insect body surface areas as an additional factor for the comparative quantification of extracted CHC amounts between our study species. CHC quantity distributions differed considerably when adjusted for body surface areas as opposed to directly assessing extracted CHC amounts, suggesting that a more accurate evaluation of relative CHC quantities can be achieved by taking body surface areas into account.

2022 ◽  
Vol 14 (2) ◽  
pp. 828
Grigorios L. Kyriakopoulos ◽  
Miltiadis G. Zamparas ◽  
Vasileios C. Kapsalis

During the last decades, one of the most contentious environmental issues has been the investigation of the fate of microplastics (MPs) and detrimental consequences in natural and water resources worldwide. In this respect, it is critical research firstly to track the ways in which MPs are determined as key anthropogenic pollutants in terms of ecological risk and secondly to plan feasible policies under which the role of science and society in tackling this global issue in the future should be prioritized. In this study, a systematic theoretical, technical, and planning analysis was developed in alignment with a Scopus search deployed in the second half of the year 2021 and covering a wide chronological range (from 1970s onwards) and thematic contexts of analysis by using keywords and key phrases organized into two groups. The document results were graphically represented, revealing the main scientific focus of studies. Subsequently, our study investigated the quantitative assessment methods of MPs in marine environments, denoting the range of standard procedures applied for collecting and analyzing samples of water, bottom sediments, and coastal deposits. The technological part of the study includes the presentation of the relevant analytical techniques applied for MPs tracking and monitoring in water resources, determining the wide spectrum of plastic compounds traced. Of particular interest was the determination of environmental depletion and human implications caused, even by extremely low concentrations of MPs, for marine biota, posing potential risks to marine ecosystems, biodiversity, and food availability. Finally, the research proposed the challenges of actions needed to support scientific, industry, policy, and civil society communities to curb the ongoing flow of MPs and the toxic chemicals they contain into water resources, while rethinking the ways of plastics consumption by humanity.

2022 ◽  
Stephen Ellis Cox ◽  
Hayden Bryce Dutcher Miller ◽  
Florian Hofmann ◽  
Kenneth Anthony Farley

Abstract. A pervasive challenge in noble gas geochemistry is to ensure that analytical techniques do not modify the composition of the noble gases in the samples. Noble gases are present in the atmosphere and are used in a number of manufacturing procedures and by laboratory equipment. Of particular concern is the introduction of atmospheric or laboratory noble gases to samples during preparation before samples are placed in a vacuum chamber for analysis. Recent work has shown the potential for contamination of crushed samples with air-derived He that is not released by placing the samples under vacuum at low temperature. Using pure He gas as a tracer, we show that the act of crushing samples to a fine powder itself can introduce He contamination, but that this is easily avoided by crushing under liquid or in an inert atmosphere. Because the He is trapped during crushing, the same concern does not extend to samples that are naturally fine-grained when collected. The degree of He contamination even from crushing samples to sizes smaller than typically used for geochronology is insignificant for samples at least 1 Ma and with more than 1 ppm U when the guidelines outlined here are followed.

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