Filtering by Subject: Analytical Chemistry
Published: 2023-03-10
Subjects: Analytical Chemistry, Geochemistry
We use 145Nd/146Nd for instrumental mass fractionation correction to accurately determine radiogenic 143Nd/144Nd for natural samples without requiring Sm elimination from Nd fraction. Conventionally, radiogenic Nd isotope ratios are expressed relative to the non-radiogenic 144Nd which is an isobar of 144Sm. To mitigate this problem, traditional analysis methods eliminate Sm entirely from the [...]
Published: 2022-07-23
Subjects: Agriculture, Analytical Chemistry, Biogeochemistry, Environmental Chemistry, Environmental Sciences, Organic Chemistry, Physical Chemistry, Soil Science
The retention of glyphosate is strongly governed by adsorption and desorption processes at environmental interfaces. In particular, glyphosate can react with organo-mineral associations (OMAs) in soils, sediments, and aquatic environments. Here, we use in-situ time-resolved attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy to provide a mechanistic understanding of [...]
Published: 2021-12-10
Subjects: Analytical Chemistry, Biogeochemistry, Chemistry, Earth Sciences, Environmental Chemistry, Environmental Monitoring, Environmental Sciences, Geochemistry, Physical Sciences and Mathematics
The Pearl River drains the second largest watershed in China, funnelling large amounts of freshwater and organic matter into the northern part of the South China Sea through an estuary characterized by pronounced biogeochemical gradients. In this study we analyzed organic extracts of surface sediments collected along land-sea transect that captures a transition from freshwater environment at the [...]
Published: 2020-07-17
Subjects: Analytical Chemistry, Chemistry, Earth Sciences, Environmental Chemistry, Environmental Monitoring, Environmental Sciences, Multivariate Analysis, Optics, Physical Sciences and Mathematics, Physics, Sedimentology, Statistical Models, Statistics and Probability
Hyperspectral imaging (HSI) is a non-destructive high-resolution sensor, which is currently under significant development to analyze geological areas with remote devices or natural samples in a laboratory. In both cases, the hyperspectral image provides several sedimentary structures that need to be separated to temporally and spatially describe the sample. Sediment sequences are composed of [...]
Published: 2019-02-21
Subjects: Analytical Chemistry, Chemistry, Earth Sciences, Environmental Chemistry, Environmental Monitoring, Environmental Sciences, Optics, Physical Sciences and Mathematics, Physics, Sedimentology, Statistical Models, Statistics and Probability
In the case of environmental samples, the use of a chemometrics-based prediction model is highly challenging because of the difficulty in experimentally creating a well-ranged reference sample set. In this study, we present a methodology using short wave infrared hyperspectral imaging to create a partial least squares regression model on a cored sediment sample. It was applied to a sediment core [...]