scholarly journals Reconciling early Deccan Traps CO2 outgassing and pre-KPB global climate

2021 ◽  
Vol 118 (14) ◽  
pp. e2007797118
Author(s):  
Andres Hernandez Nava ◽  
Benjamin A. Black ◽  
Sally A. Gibson ◽  
Robert J. Bodnar ◽  
Paul R. Renne ◽  
...  
Keyword(s):  
Trace Element ◽  
High Pressures ◽  
Melt Inclusion ◽  
Global Climate ◽  
Deccan Traps ◽  
Vapor Bubbles ◽  
Raman Spectroscopic ◽  
Spectroscopic Analyses ◽  
Direct Measurements ◽  
The Western Ghats

A 2 to 4 °C warming episode, known as the Latest Maastrichtian warming event (LMWE), preceded the Cretaceous–Paleogene boundary (KPB) mass extinction at 66.05 ± 0.08 Ma and has been linked with the onset of voluminous Deccan Traps volcanism. Here, we use direct measurements of melt-inclusion CO2 concentrations and trace-element proxies for CO2 to test the hypothesis that early Deccan magmatism triggered this warming interval. We report CO2 concentrations from NanoSIMS and Raman spectroscopic analyses of melt-inclusion glass and vapor bubbles hosted in magnesian olivines from pre-KPB Deccan primitive basalts. Reconstructed melt-inclusion CO2 concentrations range up to 0.23 to 1.2 wt% CO2 for lavas from the Saurashtra Peninsula and the Thakurvadi Formation in the Western Ghats region. Trace-element proxies for CO2 concentration (Ba and Nb) yield estimates of initial melt concentrations of 0.4 to 1.3 wt% CO2 prior to degassing. Our data imply carbon saturation and degassing of Deccan magmas initiated at high pressures near the Moho or in the lower crust. Furthermore, we find that the earliest Deccan magmas were more CO2 rich, which we hypothesize facilitated more efficient flushing and outgassing from intrusive magmas. Based on carbon cycle modeling and estimates of preserved lava volumes for pre-KPB lavas, we find that volcanic CO2 outgassing alone remains insufficient to account for the magnitude of the observed latest Maastrichtian warming. However, accounting for intrusive outgassing can reconcile early carbon-rich Deccan Traps outgassing with observed changes in climate and atmospheric pCO2.

Raman spectroscopic study of the photoprotection of extremophilic microbes against ultraviolet radiation

2006 ◽  
Vol 5 (4) ◽  
pp. 313-318 ◽  
Author(s):  
H.G.M. Edwards ◽  
R. Moeller ◽  
S.E. Jorge Villar ◽  
G. Horneck ◽  
E. Stackebrandt
Keyword(s):  
Deinococcus Radiodurans ◽  
Survival Strategies ◽  
Raman Spectroscopic ◽  
Spectroscopic Analyses ◽  
Terrestrial Habitats ◽  
Life Context ◽  
Wavelength Radiation ◽  
Spectroscopic Instrumentation ◽  
Natronomonas Pharaonis ◽  
Uva Radiation

Extremophiles use a range of pigments for protection against low-wavelength radiation in exposed terrestrial habitats and photoaccessory materials are synthesized for the effective harnessing of photosynthetically active radiation. Raman spectroscopy has been demonstrated to be a useful probe for information on the survival strategies employed by extremophilic bacteria through the identification of key biomolecular signatures of the suite of protective chemicals synthesized by the organisms in stressed environments. Raman spectroscopic analyses of Bacillus spp. spores, Bacillus atrophaeus (DSM 675: deep red) and Bacillus subtilis (DSM 5611: light grey and DSM 7264: dark grey), Deinococcus radiodurans (pink) and Natronomonas pharaonis (red), of visually different pigmentation showed the presence of different carotenoids and other protectant biomolecules, which assist microorganisms against UVA radiation. The implications for the survival of extremophilic microbes in extraterrestrial habitats and for the detection of the protectant biomolecules by remote, robotic Raman spectroscopic instrumentation in an astrobiological search for life context are discussed.

scholarly journals Characterization of Two Historical Postage Stamps Made from Cotton Fibers and Their Restoration Trials Based on the Experimental Studies

2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
Maisa M.A. Mansour ◽  
Yassin E. Zidan ◽  
Abou El Fettouh A Abd El Hakim ◽  
Mohamed Mahmoud Allam ◽  
Hayssam M. Ali ◽  
...  
Keyword(s):  
Color Change ◽  
Linseed Oil ◽  
Experimental Studies ◽  
Gum Arabic ◽  
Oxidation Reactions ◽  
Raman Spectroscopic ◽  
Ultramarine Blue ◽  
Spectroscopic Analyses ◽  
Postage Stamps ◽  
Printing Inks

Ancient stamps are suffering from the destructive effects of different kinds of inks that were prepared from different ingredients. Two Egyptian historical postage stamps printed in blue and red printing inks were evaluated and examined for their composition using a light microscope, SEM-EDS, FTIR, and Raman spectroscopic analyses. Mechanical, chemical, and deacidification treatments were done for the two stamps. Model stamps were made from the cotton pulp in the book house to simulate historical stamp paper with an average thickness of 11 microns. The unprinted and printed paper samples with printing inks that aged and unaged were treated with 0.7% Klucel G, 0.2% TiO2 NP, or a mixture of 0.7% Klucel G + 0.2% TiO2 NP, and the color change was measured and compared with the blank samples. The two stamps are suffering from high pH, where the margin color of the stamps changed to yellow-brown with weakness of the stamp paper. By SEM examination, stamps have suffered from fibers’ weakness and dryness resulting from the self-oxidation reactions. EDS elemental composition of the red stamp showed the presence of C, O, Na, Al, Si, Mg, S, Ca, Ba, and Fe, while in the blue stamp, it was C, O, Na, Al, Si, P, S, Cl, and Ca. Raman spectrometer wavelengths turn out that the blueprinting ink of the stamp was characterized with spectra of ultramarine blue (lazurite), while hematite was characterized by the red stamp. FTIR analysis for the printing inks identified that gum Arabic sample and linseed oil were the binding and color medium, respectively. From the model trials, it was observed that the treatment of a mixture of Klucel G and TiO2 NP had the best properties for the consolidation of stamps. The two historical stamps were documented through different spectroscopic analyses, and from the restoration trials, it was observed that the mixture of 7% Klucel G + 0.2% TiO2 NP appeared to be a new and effective method for recovering the historical postage stamps.

scholarly journals Groundwater Storage Changes Derived from GRACE and GLDAS on Smaller River Basins—A Case Study in Poland

Geosciences ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 124 ◽  
Author(s):  
Zofia Rzepecka ◽  
Monika Birylo
Keyword(s):  
Global Climate ◽  
Groundwater Storage ◽  
Direct Measurements ◽  
Global Land ◽  
Snow Water ◽  
Land Data Assimilation ◽  
High Consistency ◽  
Gravity Recovery ◽  
Very High

In the era of global climate change, the monitoring of water resources, including groundwater, is of fundamental importance for nature, agriculture, economy and society. The purpose of this paper is to check compliance of changes in groundwater level obtained from direct measurements in wells with groundwater storage (GWS) anomalies calculated using gravity recovery and climate experiment (GRACE) observations in Poland. Data from the global land data assimilation (GLDAS), in the form of soil moisture (SM) and snow water equivalence (SWE), were used to convert GRACE observations into a series of GWS changes. It was found that very high consistency occurs between GRACE observations and changes in water level in wells, while the GWS series obtained from GRACE and GLDAS do not provide adequate compatibility. Further research presented in the paper was devoted to attempts to explain this phenomenon. In addition, time series of GRACE, GLDAS and groundwater head series were analyzed.

scholarly journals Raman spectroscopic investigations on delafossite CuLaO2at high pressures

2012 ◽  
Vol 377 ◽  
pp. 012020 ◽  
Author(s):  
Nilesh P Salke ◽  
Rekha Rao ◽  
S N Achary ◽  
A K Tyagi
Keyword(s):  
High Pressures ◽  
Raman Spectroscopic ◽  
Spectroscopic Investigations
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