Composite Passive Layers of Ni(OH)2/Poly-(Neutral Red) on Nickel in a Weakly Acid Sulphate Medium Grown under Potentiodynamic Conditions

2019 ◽  
Vol 6 (24) ◽  
pp. 79-95 ◽  
Author(s):  
Francisco Vicente ◽  
Jerónimo Agrisuelas ◽  
Claude Gabrielli ◽  
José Juan J. García-Jareño ◽  
David Giménez-Romero ◽  
...  
Keyword(s):  
Neutral Red ◽  
Weakly Acid ◽  
Acid Sulphate

Transfer of Neutral Red into the Stomach

1958 ◽  
Vol 35 (4) ◽  
pp. 357-368 ◽  
Author(s):  
V. Varró ◽  
T. Jávor
Keyword(s):  
Neutral Red

Extraction of copper from acid sulphate solutions by 2-hydroxy-5-n-nonyl and 2-hydroxy-4′-n-nonylbenzophenone oximes

1981 ◽  
Vol 31 (1) ◽  
pp. 333-340 ◽  
Author(s):  
Stefan Goszczyński ◽  
Jan Szymanowski ◽  
Aleksandra Borowiak-Resterna
Keyword(s):  
Acid Sulphate

Optimization of sol-gel based fibre-optic cholinesterase biosensor for the determination of organophosphorus pesticides

2000 ◽  
Vol 42 (7-8) ◽  
pp. 283-290 ◽  
Author(s):  
H.-C. Tsai ◽  
R.-A. Doong
Keyword(s):  
Fiber Optic ◽  
Ph Value ◽  
Rapid Determination ◽  
Organophosphorus Pesticides ◽  
Sol Gel ◽  
Neutral Red ◽  
Fluorescent Indicators ◽  
Low Leakage ◽  
Fiber Optic System

A sol-gel based fiber-optic biosensor with acetylcholinesterase as the biorecognition element has been developed for the rapid determination of organophosphorus pesticides. Nine fluorescent indicators, acridine, acridine orange, neutral red, DAPI, rhodamine B, fluorescein, umbelliferone, FITC on celite and FITC-dextran, have been examined to optimize the fiber-optic system. Results showed that acridine and FITCs were sensitive to the change of pH value caused by the enzyme-substrate catalysis reaction. However, the sensitivity of acridine was 260 times lower than that of FITCs. Higher toxicity of acridine to acetylcholinesterase than FITC was also observed. Moreover, the high-molecular-weight FITC-dextran showed low leakage rate when immobilizing using sol-gel technology, showing that the FITC-dextran was a suitable pH sensitive fluorescent indicator for the OPPs biosensor. The response of the fiber-optic biosensor to the substrate, acetylcholine, was highly reproducible (RSD=3.5%). A good linearity of acetylcholine in the range from 0.5 to 20 mM was also obtained (R2=0.98). Furthermore, a 30% inhibition can be achieved in 30min when 152 ppb paraoxon was added into the system. The results show the possibility for real-time determination of organophosphorus pesticides by using the biosensor developed in this study.

Oxidation of ethylenediphosphinetetraacetate anions

1983 ◽  
Vol 48 (9) ◽  
pp. 2604-2608
Author(s):  
Jana Podlahová ◽  
Jaroslav Podlaha
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Electronic Structure ◽  
Acid Solutions ◽  
Tetraacetic Acid ◽  
Single Product ◽  
Weakly Acid ◽  
Inhibiting Effect ◽  
Oxidation By Molecular Oxygen ◽  
Protonated Forms

The oxidation of the ethylenediphosphinetetraacetate anion and its protonated forms by iodine, periodate, hydrogen peroxide, and oxygen has been studied in aqueous solution. The oxidation by the first three reagents is fast and yields a single product, bis(phosphine oxide), which has been isolated and characterized as ethylenebis(phosphinyl)tetraacetic acid. The oxidation by molecular oxygen proceeds considerably more slowly; in weakly acid solutions its rate is determined by the properties of the oxygen rather than by the electronic structure of the various protonated substrate species. The inhibiting effect of the phosphonium structures takes place only in strongly acid solutions.

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