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You searched for: Subject acidification Remove constraint Subject: acidification Subject term chemical species Remove constraint Subject term: chemical species
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1. CO2 per se activates carbon dioxide receptors

Author:
Pingxi Xu; Xiaolan Wen; Walter S. Leal
Source:
Insect biochemistry and molecular biology 2020 v.117 pp. 103284
ISSN:
0965-1748
Subject:
Culex quinquefasciatus; Drosophilidae; Xenopus; acidification; carbon dioxide; chemical species; malaria; neurons; oocytes; palps; receptors; sodium bicarbonate; taste; yellow fever
Abstract:
... Carbon dioxide has been used in traps for more than six decades to monitor mosquito populations and help make informed vector management decisions. CO₂ is sensed by gustatory receptors (GRs) housed in neurons in the maxillary palps. CO₂-sensitive GRs have been identified from the vinegar fly and mosquitoes, but it remains to be resolved whether these receptors respond to CO₂ or bicarbonate. As opp ...
DOI:
10.1016/j.ibmb.2019.103284
PubMed:
31760135
PubMed Central:
PMC6980743

2. Comparison of the Effects of Extraction Techniques on Mass Spectrometry Profiles of Dissolved Organic Compounds in Oil Sand Process-Affected Water

Author:
Hattan A. Alharbi; Garrett D. Morandi; Paul D. Jones; Steve B. Wiseman; John P. Giesy
Source:
Energy & fuels 2019 v.33 no.8 pp. 7001-7008
ISSN:
1520-5029
Subject:
acidification; chemical species; hydrophilicity; lipophilicity; liquid-liquid extraction; mass spectrometry; metals; naphthenates; nitrogen; oil sands; pH; particulates; solid phase extraction; sorbents; sulfur
Abstract:
... Recent advances in mass spectrometry have facilitated chemical characterization and profiling of complex environmental mixtures such as oil sand process-affected water (OSPW) and identification of previously unresolved chemicals. However, because OSPW is a complex mixture of salts, metals, suspended particulate matter, and dissolved organics, extraction techniques are required to reduce the effect ...
DOI:
10.1021/acs.energyfuels.9b00813

3. Determination of UV-327 and its metabolites in human urine using dispersive liquid-liquid microextraction and gas chromatography-tandem mass spectrometry

Author:
Corinna Fischer; Thomas Göen
Source:
Analytical methods 2021 v.13 no.35 pp. 3978-3986
ISSN:
1759-9679
Subject:
acidification; chemical species; chloroform; derivatization; enzymatic hydrolysis; humans; hydrochloric acid; isopropyl alcohol; liquid-phase microextraction; metabolism; metabolites; pH; sodium chloride; solvents; stabilizers; tandem mass spectrometry; triazoles; urine
Abstract:
... The benzotriazole UV stabilizer (BUVS) 2-(5-chloro-benzotriazol-2-yl)-4,6-di-(tert-butyl)phenol (UV-327) is added to plastic materials for UV protection. The compound is known to be ubiquitously distributed in the environment. We developed the first analytical method for the determination of UV-327 and seven metabolites, which were identified in vitro, in urine to be able to investigate the in viv ...
DOI:
10.1039/d1ay00932j

4. Development and validation of a GC-FID method for the analysis of short chain fatty acids in rat and human faeces and in fermentation fluids

Author:
Serena Scortichini; Maria Chiara Boarelli; Stefania Silvi; Dennis Fiorini
Source:
Journal of chromatography 2020 v.1143 pp. 121972
ISSN:
1570-0232
Subject:
acetic acid; acidification; chemical species; derivatization; ethyl ether; feces; fermentation; flame ionization; hexanoic acid; humans; intestinal microorganisms; metabolites; mice; polyethylene glycol; propionic acid; quantitative analysis; rats
Abstract:
... Short-chain fatty acids (SCFAs) are gut microbiota metabolites recognized for their beneficial effects on the host organism. In this study, a simple and rapid sample preparation method combined to SCFAs analysis by direct injection and gas chromatography coupled with flame ionization detection (GC-FID), for the determination and quantification of eight SCFAs (acetic, propionic, i-butyric, butyric, ...
DOI:
10.1016/j.jchromb.2020.121972

5. From sea salt to seawater: a novel approach for the production of water CRMs

Author:
Enea Pagliano; Kenny Nadeau; Ovidiu Mihai; Indumathi Pihillagawa Gedara; Zoltán Mester
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.16 pp. 4745-4756
ISSN:
1618-2642
Subject:
acidification; analytical chemistry; aqueous solutions; chemical species; filtration; isotope dilution technique; liquids; molybdenum; nitrates; nutrient content; pH; phosphates; photometry; seawater; silicates
Abstract:
... Natural water certified reference materials (CRMs) are mostly available in a liquid form, and they are produced starting from suitable environmental samples. Many precautions are usually needed to avoid biological or physical degradation, including filtration, acidification, and sterilization. In this study, the drawbacks associated with liquid-based seawater CRMs were tackled by developing a salt ...
DOI:
10.1007/s00216-022-04098-0

6. Impact of mechanical disturbance and acidification on the metal(loid) and C, P, S mobility at the sediment water interface examined using a fractionation meso profiling ICP-QQQ-MS approach

Author:
Henning Schroeder; Anne-Lena Fabricius; Dennis Ecker; Thomas A. Ternes; Lars Duester
Source:
Science of the total environment 2019 v.651 pp. 2130-2138
ISSN:
0048-9697
Subject:
acidification; air; antimony; arsenic; cadmium; chemical species; chromium; cobalt; copper; fractionation; iron; lead; manganese; nickel; oxygen; pH; redox potential; sediment-water interface; spectroscopy
Abstract:
... The impact of mechanical disturbance and oxygen induced acidification on the concentration and size fractionation of the 12 metal(loid)s As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Tl, V and the polyatomic nonmetals C, P and S in the pore water was studied. Using the meso profiling and sampling system (messy) 12 pore water depth profiles were sampled from two incubation experiments undertaken in paral ...
DOI:
10.1016/j.scitotenv.2018.09.390

7. Influence of Acidification on the Partitioning of Steroid Hormones among Filtrate, Filter Media, and Retained Particulate Matter

Author:
Sonya M. Havens; Curtis J. Hedman; Jocelyn D.C. Hemming; Mark G. Mieritz; Martin M. Shafer; James J. Schauer
Source:
Journal of environmental quality 2016 v.45 no.5 pp. 1776-1781
ISSN:
0047-2425
Subject:
acidification; aquatic environment; chemical species; filtrates; high performance liquid chromatography; isotope labeling; melengestrol; pH; particulates; progesterone; quantitative analysis; runoff; steroid hormones; surface water
Abstract:
... Hormone contamination of aquatic systems has been shown to have deleterious effects on aquatic biota. However, the assessment of hormone contamination of aquatic environments requires a quantitative evaluation of the potential effects of sample preservation on hormone concentrations. This study investigated the influence of acidification (pH 2) of surface water samples on the partitioning of hormo ...
DOI:
10.2134/jeq2016.01.0017

8. Interactions between pH, reactive species, and cells in plasma-activated water can remove algae

Author:
Ken Mizoi; Vicente Rodríguez-González; Mao Sasaki; Shoki Suzuki; Kaede Honda; Naoya Ishida; Norihiro Suzuki; Kazuyuki Kuchitsu; Takeshi Kondo; Makoto Yuasa; Akira Fujishima; Katsuya Teshima; Chiaki Terashima
Source:
RSC advances 2022 v.12 no.13 pp. 7626-7634
ISSN:
2046-2069
Subject:
Chlorella vulgaris; acidification; algae; basil; chemical species; fertilizer rates; ion exchange chromatography; iridium; lightning; nitrogen; oxygen; pH; reactive nitrogen species; ultraviolet-visible spectroscopy
Abstract:
... Lightning strikes cause nitrogen to dissolve in water and form reactive nitrogen and oxygen species, which form natural fertilizers that can be absorbed through plant roots. Such processes during rainstorm events can be simulated by applying plasma to a solution. Plasma-activated water (PAW) has great potential as a source of various dissolved reactive chemical species. Different mixtures of speci ...
DOI:
10.1039/d1ra07774k

9. LC‐MS/MS methods for determination of unstable pivmecillinam and mecillinam in acidified human plasma: Application to a pharmacokinetic study

Author:
Lu‐Ning Sun; Yang Zhao; Hua‐Ye Gao; Yan‐Ling Yang; Xu‐Ping Qian; Shi‐Yu Sun; Yu Wang; Li Ding; Yong‐Qing Wang
Source:
Journal of separation science 2022 v.45 no.14 pp. 2543-2554
ISSN:
1615-9306
Subject:
acetonitrile; acidification; cephalexin; chemical species; formic acid; humans; methanol; oral administration; pharmacokinetics; separation; urinary tract
Abstract:
... Pivmecillinam, the ester of biologically active antibiotic mecillinam, is an effective oral preparation to treat urinary tract infections. To study pharmacokinetics in humans, LC‐MS/MS methods were developed to quantify pivmecillinam and mecillinam in human plasma, respectively. Considering cephalexin as internal standard, analytes were separated on UltimateXB‐C18 columns after protein precipitati ...
DOI:
10.1002/jssc.202200070

10. Methods for simultaneous determination of legacy and insensitive munition (IM) constituents in aqueous, soil/sediment, and tissue matrices

Author:
Rebecca A. Crouch; Jared C. Smith; Bobbi S. Stromer; Christian T. Hubley; Samuel Beal; Guilherme R. Lotufo; Afrachanna D. Butler; Michelle T. Wynter; Amber L. Russell; Jessica G. Coleman; Katrinka M. Wayne; Jay L. Clausen; Anthony J. Bednar
Source:
Talanta 2020 v.217 pp. 121008
ISSN:
0039-9140
Subject:
2,4-dinitrophenol; acidification; benzoic acids; chemical species; environmental protection; high performance liquid chromatography; mass spectrometry; p-nitrophenol; sediments; soil types; solid phase extraction; solvents
Abstract:
... Currently, no standard method exists for analyzing insensitive munition (IM) compounds in environmental matrices, with or without concurrent legacy munition compounds, resulting in potentially inaccurate determinations. The primary objective of this work was to develop new methods of extraction, pre-concentration, and analytical separation/quantitation of 17 legacy munition compounds along with se ...
DOI:
10.1016/j.talanta.2020.121008

11. Quantitative analysis of polycyclic aromatic hydrocarbons using high‐performance liquid chromatography‐photodiode array‐high‐resolution mass spectrometric detection platform coupled to electrospray and atmospheric pressure photoionization sources

Author:
Anusha Priyadarshani Silva Hettiyadura; Alexander Laskin
Source:
Journal of mass spectrometry 2022 v.57 no.2 pp. e4804
ISSN:
1076-5174
Subject:
absorbance; absorption; acidification; air quality; atmospheric pressure; carcinogenicity; chemical composition; chemical species; climate; electrospray ionization mass spectrometry; formic acid; human health; ionization; pollutants; quantitative analysis; solar radiation; wavelengths
Abstract:
... Polycyclic aromatic hydrocarbons (PAHs) are common pollutants present in atmospheric aerosols and other environmental mixtures. They are of particular air quality and human health concerns as many of them are carcinogenic toxins. They also affect absorption of solar radiation by aerosols, therefore contributing to the radiative forcing of climate. For environmental chemistry studies, it is advanta ...
DOI:
10.1002/jms.4804

12. Seashore sediment and water chemistry at the Admiralty Bay (King George Island, Maritime Antarctica) – Geochemical analysis and correlations between the concentrations of chemical species

Author:
Joanna Potapowicz; Danuta Szumińska; Małgorzata Szopińska; Robert Józef Bialik; Katarzyna Machowiak; Stanisław Chmiel; Żaneta Polkowska
Source:
Marine pollution bulletin 2020 v.152 pp. 110888
ISSN:
0025-326X
Subject:
acidification; chemical species; climate change; ecology; glaciers; hydrochemistry; lakes; marine pollution; mineral content; riparian areas; sediments; Antarctica
Abstract:
... This study covers water and sediment chemical characteristics by the western shore of Admiralty Bay (King George Island, Antarctica) in 2016. Chemical processes between sediment and water have been described based on the determination of ions, metals, non-metals, and TOC concentrations. Rock weathering is an important source of Fe, Ni, Co, Al in the seashore area. The PCA shows the impact of acidi ...
DOI:
10.1016/j.marpolbul.2020.110888

13. Sediment porewater extraction and analysis combining filter tube samplers and capillary electrophoresis

Author:
Natascha T. Torres; Peter C. Hauser; Gerhard Furrer; Helmut Brandl; Beat Müller
Source:
Environmental science 2013 v.15 no.4 pp. 715-720
ISSN:
2050-7895
Subject:
acidification; air; ammonium; anions; biogeochemistry; calcium; capillary electrophoresis; chemical species; detection limit; iron; lakes; magnesium; manganese; oxidation; potassium; samplers; sampling; sediments; sodium; water content; Switzerland
Abstract:
... Careful extraction and analysis of porewater from sediment cores are critical for the investigation of small-scale biogeochemical processes. Firstly, small sample volumes and high spatial resolution are required. Secondly, several chemical species in the anaerobic porewater are sensitive to oxidation when brought in contact with ambient air. Here we present the combination of a special sampling te ...
DOI:
10.1039/c3em00068k

14. Stir membrane liquid phase microextraction of tetracyclines using switchable hydrophilicity solvents followed by high-performance liquid chromatography

Author:
Sofya Lebedinets; Christina Vakh; Ksenya Cherkashina; Aleksei Pochivalov; Leonid Moskvin; Andrey Bulatov
Source:
Journal of chromatography 2020 v.1615 pp. 460743
ISSN:
0021-9673
Subject:
acidification; calibration; chemical species; chlortetracycline; graphs; high performance liquid chromatography; hydrophilicity; hydrophobicity; liquid-phase microextraction; medium chain fatty acids; oxytetracycline; porosity; regression analysis; separation; solvents; surface area; tetracycline; water solubility
Abstract:
... A novel approach for stir membrane liquid phase microextraction of tetracyclines from biological fluids was developed. The microextraction procedure assumed in situ formation of microdroplets of a hydrophobic medium-chain fatty acid (extraction solvent) from homogeneous sample solution containing water-soluble medium-chain fatty acid salt by acidification and simultaneous analytes extraction and o ...
DOI:
10.1016/j.chroma.2019.460743

15. Stir membrane liquid-phase microextraction based on milk fats hydrolysis and deep eutectic solvent formation: Determination of bisphenols

Author:
Andrey Shishov; Pavel Terno; Makar Besedovsky; Andrey Bulatov
Source:
Food chemistry 2023 v.403 pp. 134408
ISSN:
0308-8146
Subject:
acidification; alkaline hydrolysis; chemical species; food chemistry; hydrophobicity; liquid-phase microextraction; menthol; milk; solvents; water solubility
Abstract:
... In this paper, a stir membrane liquid-phase microextraction approach based on milk fats hydrolysis and in situ deep eutectic solvent formation was developed for the first time. The approach was applied to clean-up and preconcentrate bisphenols from milk samples. The procedure assumed alkaline hydrolysis of samples fats to obtain water-soluble salts of fatty acids that acted as precursors for the d ...
DOI:
10.1016/j.foodchem.2022.134408

16. Temperature and Microbial Activity Effects on Trace Element Leaching from Metalliferous Peats

Author:
Shabnam Qureshi; Brian K. Richards; Murray B. McBride; Philippe Baveye; Tammo S. Steenhuis
Source:
Journal of environmental quality 2003 v.32 no.6 pp. 2067-2075
ISSN:
1537-2537
Subject:
acid deposition; acidification; aeration; arsenic; cadmium; chemical species; copper; dissolved organic carbon; drainage; geochemistry; glass; glucose; leachates; leaching; microbial activity; mineralization; nickel; nitrate nitrogen; pH; peat; peat soils; temperature; zinc; New York
Abstract:
... Due to geochemical processes, peat soils often have elevated concentrations of trace elements, which are gradually released following drainage for agriculture. Our objectives were to use incubation temperatures to vary microbial activity in two metalliferous peats (M7 acidic peat and M3 neutral peat) from the Elba, New York region, and to use periodic leaching to assess the extent of trace element ...
DOI:
10.2134/jeq2003.2067

17. The design of responsive luminescent lanthanide probes and sensors

Author:
David Parker; Jack D. Fradgley; Ka-Leung Wong
Source:
Chemical Society reviews 2021 v.50 no.14 pp. 8193-8213
ISSN:
1460-4744
Subject:
G-proteins; acidification; bicarbonates; blood serum; chemical species; citrates; drugs; electron transfer; energy transfer; lanthanides; ligands; luminescence; mechanism of action; moieties; pH; reactive oxygen species; temperature
Abstract:
... The principles of the design of responsive luminescent probes and sensors based on lanthanide emission are summarised, based on a mechanistic understanding of their mode of action. Competing kinetic pathways for deactivation of the excited states that occur are described, highlighting the need to consider each of the salient quenching processes. Such an analysis dictates the choice of both the lig ...
DOI:
10.1039/d1cs00310k

18. A novel pharmaceutical approach for the analytical validation of probiotic bacterial count by flow cytometry

Author:
Luca Michelutti; Michela Bulfoni; Emanuele Nencioni
Source:
Journal of microbiological methods 2020 v.170 pp. 105834
ISSN:
0167-7012
Subject:
Bifidobacterium; Lactobacillus; acidification; bacteria; biochemical pathways; cell viability; chemical species; computer software; data analysis; dietary supplements; drugs; fermentation; flow cytometry; fluorescent dyes; humans; oxygen; plate count; probiotics; propidium; thiazoles
Abstract:
... Introduction: Flow cytometry is a powerful and sensitive technique able to characterize single cells within a heterogeneous population. Different fluorescent dyes can be combined and used together to analyze a great variety of parameters simultaneously. In particular, flow-cytometry allows to measure viability and vitality of probiotics measuring their metabolic activity, fermentation capacity, ac ...
DOI:
10.1016/j.mimet.2020.105834