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Graphene-based Materials as Highly Promising Catalysts for Energy Storage and Conversion Applications
Published in Esteban A. Franceschini, Nanostructured Multifunctional Materials Synthesis, Characterization, Applications and Computational Simulation, 2021
Maximina Luis-Sunga, Stephanie J. Martínez, José Luis Rodríguez, Gonzalo García, Elena Pastor
Sulfur doped graphene-based catalysts were prepared by Morales-Acosta et al. Graphene oxide was synthesized, reduced and further sulfonated (Morales-Acosta et al. 2019). The reduction was carried out through a chemical and thermal process, performing the functionalization using sulfuric acid or aryl diazonium salt of sulfanilic acid as sulfonating agents, obtaining rGO-SO3H. The rGO-SO3H catalyst thermally reduced and doped with sulfuric acid showed better electron transfer activity compared to that chemically reduced and sulfonated with sulfanilic acid (Morales-Acosta et al. 2019).
Student-Tested Laboratory Experiments
Published in Paul R. Loconto, Trace Environmental Quantitative Analysis, 2020
The major limitation on the use of visible spectrophotometric or colorimetric methods is the fact that the analyte must absorb within the visible domain of the electromagnetic spectrum. Many analytes of environmental interest are colorless! Some analytes can be chemically converted to a colored product by direct chemical change, formation of a metal chelate, or formation of an ion pair. An example of a chemical conversion of the analyte of interest is the colorimetric determination of nitrite–nitrogen via reaction of the nitrite ion with sulfanilic acid in acidic media to form the diazonium salt, with subsequent reaction with chromotropic acid to form a highly colored azo dye as shown:
Introduction to the Visible Spectrophotometer
Published in Paul R. Loconto, Laboratory Experiments in Trace Environmental Quantitative Analysis, 2022
The major limitation of the use of visible spectrophotometric or colorimetric methods is the fact that the analyte must absorb within the visible domain of the electromagnetic spectrum. Many analytes of environmental interest are colorless! Some analytes can be chemically converted to a colored product by a direct chemical change, formation of a metal chelate, or formation of an ion pair. An example of a chemical conversion of the analyte of interest is the colorimetric determination of nitrite–nitrogen via reaction of the nitrite ion with sulfanilic acid in acidic media to form the diazonium salt, with subsequent reaction with chromotropic acid to form a highly colored azo dye as shown:
Effect of sulphate and Chloride Ions on the Oxidation of Phenolic Compounds by Ozonation Catalyzed with CeO2
Published in Ozone: Science & Engineering, 2021
Iveete C. Guzmán, Julia L. Rodríguez S., T. Poznyak, Isaac Chairez
Cerium oxide (CeO2) belongs to the rare-earth oxides, it has been widely used for its exceptional luminescence, magnetic and electronic properties (Castano, O’Keefe, and Fahrenholtz 2015). The combination of CeO2 with ozone (as oxidant agent) has been tested as part of catalytic many water treatments; which is by far the most promising treatment considering its increasing of mineralization degree of organic pollutants (Afzal, Quan, and Lu 2019; Guzmán et al. 2020; Orge et al. 2011). Orge et al. (2011) showed that the synthesis method of CeO2 nanostructures affected the removal of oxalic acid, aniline, and reactive dye with ozone. In this research, the authors suggested that OH• is the main oxidant species responsible for the compound’s elimination from water, due to CeO2 promotes the ozone decomposition. Thus, CeO2 significantly increases the mineralization degree compared with conventional ozonation. Faria, Órfão, and Pereira (2008) studied ozonation of sulfanilic acid and aniline obtaining similar results over catalytic ozonation effectiveness.
Recycling rice husk for removal of phosphate and nitrate from synthetic and swine wastewater: Adsorption study and nutrient analysis of modified rice husk
Published in Journal of Environmental Science and Health, Part A, 2021
Najjapak Sooksawat, Somtop Santibenchakul, Maleeya Kruatrachue, Duangrat Inthorn
Synthetic wastewater (single solution) containing 10 mg/L of phosphate or nitrate was prepared. Analytical grade 1,000 mg/L standard solutions of phosphate (KH2PO4) and nitrate (NaNO3) were used. Batch adsorption experiments were done in 125 mL stoppered conical flasks containing 50 mL of anion solution using 3 types of sorbents: RH, BW, and CM. In a standard assay, the test solution with mixing sorbent was shaken on a reciprocal shaker at 150 rpm, 25 ± 2 °C for 2 h,[24] unless indicated otherwise, and then filtered through Whatman filter paper No.1. Each filtrate was subjected to phosphate determination using the ascorbic acid method[32] and nitrate determination using the brucine-sulfanilic acid method.[33–35] A UV-Vis spectrophotometer (Varian Cary-50, Australia) was used for absorbance measurements in both colorimetric assays.
Toxicoproteomic assessment of liver responses to acute pyrrolizidine alkaloid intoxication in rats
Published in Journal of Environmental Science and Health, Part C, 2018
Yan-Hong Li, William Chi-Shing Tai, Imran Khan, Cheng Lu, Yao Lu, Wing-Yan Wong, Wood-Yee Chan, Wen-Luan Wendy Hsiao, Ge Lin
RTS, the reduced form of glutathione (GSH), 5,5-dithiobis-2-nitrobenzonic acid, hydrogen peroxide (H2O2), bilirubin, sulfanilic acid, dimethyl sulfoxide, and sodium nitrite were purchased from Sigma-Aldrich Corporation (St. Louis, MO, USA). Acrylamide mix and siLenfect were purchased from Bio-Rad (Hercules, Calif., USA). 1, 4-Dithiothreitol (DTT), 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), sodium dodecyl sulfate (SDS), and immobilized pH gradient buffer were purchased from Amersham Biosciences (Piscataway, NJ, USA). Iodoacetamide and rat endothelial cell antibody (RECA-1) (#ab9774) were purchased from Abcam (Cambridge, MA, USA). Anti-mouse IgG antibody (#7076) was purchased from Cell Signaling Technology (Danvers, MA, USA). All other chemicals were of high purity and commercially available.