Application of bioinformatics to spectral analysis: soil organic carbon structure distinguished by X-ray photoelectron spectroscopy

AbstractThe paper deals with fabrication of carbonized and hydrophobized clinoptilolite-rich tuff using organic carbon rich substances, here particularly starch and waste vegetable residues, which were pyrolytically combusted and covered the external zeolite surface. Hydrophobization of the zeolite external surface was accomplished by octadecylammonium surfactant. Both surface modified clinoptilolite-rich tuffs were tested and compared with each other with regard to removal of organic (phenol) and inorganic (chromate, arsenate) pollutants from aqueous solutions. These elaborated composites with surface adsorbed pollutant species were analysed by X-ray photoelectron spectroscopy (XPS).

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X-RAY Photoelectron Spectroscopic Study of Cigar Lake Uranium Ore: A Natural Analog for Used Fuel

MRS Proceedings ◽

10.1557/proc-257-449 ◽

1991 ◽

Vol 257 ◽

Cited By ~ 3

Author(s):

S. Sunder ◽

J.J. Cramer ◽

N.H. Miller

Keyword(s):

High Resolution ◽

Organic Carbon ◽

Photoelectron Spectroscopy ◽

Uranium Deposit ◽

Radioactive Decay ◽

Xps Spectra ◽

X Ray ◽

Natural Analog ◽

Cutting Processes ◽

Nuclear Fuel Waste

ABSTRACTX-ray photoelectron spectroscopy (XPS) was used to study samples from the Cigar Lake uranium deposit in northern Saskatchewan. Two uranium-rich sections, CS-615 and CS-620 were studied. Peaks due to U, 0, C, Pb, Si, Ca, Al, S, Cu and Th were seen in the XPS spectra. Concentrations of Pb of up to 14 wt% were measured by XPS and correspond to the Pb ingrowth by radioactive decay during the 1.3 billion years since the ore was formed. High-resolution spectra were recorded for the U, Pb, 0, and C bands. Lead was in the +2 oxidation state in all samples. The carbon signal indicated the presence of organic carbon, while the oxygen bands indicated the presence of significant amounts of water in the samples. The samples from the CS-615 section had U6+/U4+ ratios between 0.16 and 0.29. However, the U6+/U4+ ratios for section CS-620 were about 0.7 but this is attributed to oxidation of the ore by water during the drilling and cutting processes. The significance of the results for disposal concepts in nuclear fuel waste management programs is discussed.

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Long term crop management effects on soil organic carbon, structure, and water retention in a cropland soil in central Ohio, USA

Journal of Plant Nutrition and Soil Science ◽

10.1002/jpln.201900430 ◽

2020 ◽

Vol 183 (2) ◽

pp. 200-207

Author(s):

Surender Singh Yadav ◽

Jose G. Guzman ◽

Ram Swaroop Meena ◽

Rattan Lal ◽

Gulab Singh Yadav

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Water Retention ◽

Crop Management ◽

Carbon Structure ◽

Management Effects

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Soil Organic Carbon Stabilization: Influence of Tillage on Mineralogical and Chemical Parameters

Soil Systems ◽

10.3390/soilsystems4030058 ◽

2020 ◽

Vol 4 (3) ◽

pp. 58 ◽

Cited By ~ 2

Author(s):

Francesco De Mastro ◽

Andreina Traversa ◽

Claudio Cocozza ◽

Mauro Pallara ◽

Gennaro Brunetti

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Clay Minerals ◽

Near Infrared ◽

Soil Depth ◽

Mineralogical Composition ◽

Amorphous Oxides ◽

Size Fractions ◽

X Ray ◽

Soil Fractions

The interaction of organic carbon (OC) with clay minerals and amorphous iron and aluminum oxides, especially in the finest soil fractions (<20 μm), represents a good method for its stabilization, and different tillage practices can improve or reduce the persistence of OC in soils. This study investigates the effects of conventional (CT) and no (NT) tillage and soil depth (0–30, 30–60, and 60–90 cm) on the soil organic carbon (SOC) in four soil size fractions and its interactions with clay minerals and amorphous oxides. To identify the mineralogical composition of the four soil size fractions isolated from each soil, the X-ray powder diffraction (XRPD) technique was used with near infrared (NIR) spectroscopy, while the X-ray fluorescence (XRF) technique was used to determine the chemical composition of soil fractions. The higher OC content found in the finest soil fraction is related to its higher content of clay minerals and amorphous oxides. The SOC content is similar among CT and NT treatments as well as the mineralogical composition and the amount of amorphous oxides, suggesting that more than ten years of different tillage did not influence those parameters.

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PALEOENVIRONMENTAL ANALYSIS OF A LOWER CRETACEOUS PALEOLAKE FROM THE IGUATU BASIN BASED ON ITS OSTRACOD FAUNA AND XRF DATA

Palaios ◽

10.2110/palo.2021.006 ◽

2021 ◽

Vol 36 (12) ◽

pp. 356-376

Author(s):

MARCOS ANTONIO BATISTA DOS SANTOS FILHO ◽

GERSON FAUTH ◽

BENJAMIN SAMES ◽

ERIK WOLFGRING ◽

JORGE VILLEGAS-MARTÍN

Keyword(s):

Cluster Analysis ◽

Spectral Analysis ◽

Organic Carbon ◽

Sedimentation Rate ◽

Lower Cretaceous ◽

Middle Part ◽

Sedimentation Rates ◽

Total Sulfur ◽

X Ray ◽

Paleoenvironmental Analysis

ABSTRACT This paper presents the results of a paleoenvironmental study of two Hauterivian–Aptian adjacent sections (Transnordestina A/B) of the Iguatu Basin using ostracods and aided by X-ray fluorescence (XRF), total organic carbon (TOC), total sulfur (S), and spectral analyses. Cluster analysis divided the 10 genera found into two main groups: one composed of Alicenula-Pattersoncypris?-Brasacypris-Hastacypris-Ilyocypris?, and the second composed of Cypridea-Looneyellopsis-Rhinocypris?. The first group is interpreted as representing paleoenvironments with permanent waterbodies, such as lakes, and the second as being indicative of ephemeral settings, such as temporary pools in an inundation plain. XRF analysis using the positive peaks of Ca/Ti and Ca/ΣTi, Fe, Al ratios show a few dry periods, particularly in the lower and middle part of Transnordestina A, between 0 to 175 m and 385 to 475 m, which also display a small number of ostracods. Total S shows several high peaks which might be indicative of gypsum deposition during droughts. Spectral analysis of molar Ti/Al ratio shows two intervals with different sedimentation rates, between 0 and 233 m, and 233 to 836 m. For the first interval, six 100 ka eccentricity cycles were identified; the low number of ostracods for the interval and highly variable Ca/Ti and Ca/ΣTi, Fe, Al values indicate a different sedimentation rate in a drier environment. For the second interval, ten 405 ka cycles were identified; its higher ostracod count and more stable Ca/Ti and Ca/ΣTi, Fe, Al values could be indicative of increasing humidity.

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