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Monitoring Ion Exchange Chromatography with Affordable Flame Emission Spectroscopy
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From Lignin to Valuable Aromatic Chemicals: Lignin Depolymerization and Monomer Separation via Centrifugal Partition Chromatography
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Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry: A Strategy for Optimization, Characterization, and Quantification of Antioxidant Nitro Derivatives
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Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry Analysis of Eutectic Bis(2,2-dinitropropyl) Acetal/Formal Degradation Profile: Nontargeted Identification of Antioxidant Derivatives
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Combining synchrotron vacuum-ultraviolet photoionization mass spectrometry and gas chromatography–mass spectrometry for isomer-specific mechanistic analysis with application to the benzyl self-reaction
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Exploring how exposure to radiolysis and harsh chemical reagents impact americium-241 extraction chromatography
Improving control over radiolysis would advance nuclear technologies, spanning from radiotherapeutics to national security. Herein, we studied the effects of radiolysis on large-scale production of Am-241.
Polymer characterization by size-exclusion chromatography with multi-angle light scattering (SEC-MALS): a tutorial review
We describe the theory and application of SEC-MALS with minimal equations and a focus on synthetic polymer characterization.
Gas Chromatography-Mass Spectrometry Analysis of Synthetic Opioids Belonging to the Fentanyl Class: A Review
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Detection and confirmation of fentanyls in high clay‐content soil by electron ionization gas chromatography‐mass spectrometry
Abstract Detection of illicit drugs in the environment, particularly in soils, often suggests the present or past location of a clandestine production center for these substances. Thus, development of efficient methods for the analysis and detection of these chemicals is of paramount importance in the field of chemical forensics. In this work, a method involving the extraction and retrospective confirmation of fentanyl, acetylfentanyl, thiofentanyl, and acetylthiofentanyl using trichloroethoxycarbonylation chemistry in a high clay‐content soil is presented. The soil was spiked separately with each fentanyl at two concentrations (1 and 10 μg/g) and their extraction accomplished using ethyl acetate and aqueous NH 4 OH (pH ~ 11.4) with extraction recoveries ranging from ~56% to 82% for the high‐concentration (10 μg/g) samples while ranging from ~68% to 83% for the low‐concentration (1 μg/g) samples. After their extraction, residues containing each fentanyl were reacted with 2,2,2‐trichloroethoxycarbonyl chloride (Troc‐Cl) to generate two unique and predictable products from each opioid that can be used to retrospectively confirm their presence and identity using EI‐GC‐MS. The method's limit of detection (MDL/LOD) for Troc‐norfentanyl and Troc‐noracetylfentanyl were estimated to be 29.4 and 31.8 ng/mL in the organic extracts. In addition, the method's limit of quantitation for Troc‐norfentanyl and Troc‐noracetylfentanyl were determined to be 88.2 and 95.5 ng/mL, respectively. Collectively, the results presented herein strengthen the use of chloroformate chemistry as an additional chemical tool to confirm the presence of these highly toxic and lethal substances in the environment.
Carbon dioxide (CO2) flux, amplicon sequencing and liquid chromatography–mass spectrometry (LC-MS) data for pyrogenic organic matter (PYOM) amended soil incubations in lab, Madison, WI, 2021-22
This dataset comprises soil-pyrogenic organic matter (PyOM) incubation experiments conducted in a laboratory setting. The focus was on measuring carbon dioxide (CO2) flux emitted in the headspace of incubation jars over a one-month period. The aim was to estimate carbon mineralization from two different carbon fractions in PyOM, as well as carbon mineralization from soil organic carbon (SOC). Bacterial and fungal community profiles were tracked at various time points during the incubation to observe changes in the overall community and specific responders to PyOM. LC-MS analysis of soil samples was also performed to monitor changes in the soil's chemical composition.The provided dataset includes processed CO2 flux measurements obtained from the Picarro-multiplexer measurement setup for each sample incubation jar. This data is available in the "CO2Flux.csv" file. Additionally, the dataset includes CO2 flux data partitioned to estimate mean carbon mineralization from the two PyOM carbon fractions, bulk PyOM, and SOC. The cumulative carbon mineralization data is provided in "cml_respired.csv," while the rate of carbon mineralization data is in "rate_respired.csv." The file "cml_respired_lastcyc.csv" contains cumulative carbon mineralization data for the PyOM carbon fractions, bulk PyOM, and SOC throughout the entire incubation period.For the LC-MS analysis, the raw data can be found in the "20220721_NZ_PeakHeights_FinalAnalysis.csv" file, while sample metadata is provided in "20220721_NZpilot_Metadata.csv". Processed LC-MS data is available in the file "20220721_NZ_FINAL_msdat_sub3.csv". Lastly, the dataset includes the relative abundance data for bacterial genera that exhibited a significant positive response to the addition of PyOM produced at 350 degrees Celsius, which can be found in "resp_genera_350.csv".
Recent Advances in Microfabricated Gas Chromatography for Process Analysis.
Abstract not provided.
Recent Advances in Microfabricated Gas Chromatography for Process Analysis.
Abstract not provided.
Formation and Interrogation of a Modeling Excel Database for Sorbent Preconcentration with Gas Chromatography Mass Spectroscopy .
Abstract not provided.
What is Chromatography? [Slides]
A laboratory technique for separating a mixture into its components. This is done with a mobile phase moving across a stationary phase containing the mixture. The components of the mixture will move with the mobile phase at differing speeds depending on their properties.
Design and Characterization of a Printed Circuit Board-Based Gas Chromatography Column for Greenhouse Gas Analysis
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