Screening of volatile organic pollutants in water of Almaty lake-settler by SPME-GC-MS was written by Alimzhanova, M. B.. And the article was included in Izvestiya Natsional’noi Akademii Nauk Respubliki Kazakhstan, Seriya Khimii i Tekhnologii in 2016.Quality Control of 3-Methyl-4-nitro-1H-pyrazole This article mentions the following:
Environmental problems of big cities are directly related to the high concentration of population, industry and transport in small areas, which are the cause of a large number of industrial and domestic emissions. These emissions may represent a different kind of chem. compounds: volatile,semi-volatile and toxic organic compounds, which can be merged with water and pollute it. As a result there are several so-called lake-settlers, where contaminated water is stored for further purification An annual monitoring of these lakes it is necessary carry out for to prevent the possibility of getting these compounds in drinking water and harm to the environment. The Environmental Protection Agency offered EPA 8270S method for determination volatile and semi-volatile compounds in the environmental objects by GC-MS. However, this technique is not economically profitable,since it requires the use of expensive reference materials for calibration curve and set retention times of all 210 compounds and organic solvents for extraction The aim of this work is to develop a new selective, informative and efficient green method for the detection of VOCs in water without using organic solvents for extraction and without require of use expensive standard samples. Method of solid phase microextraction and GC/MS with identification of peaks by Kovatc’s indexes is the most appropriate responding to all requests for the detection of VOCs in the environment. The green method will enable to determine VOCs in environmental objects. Results of work included the optimization of SPME parameters and calculation of retention times of n-alkanes. Using the retention times and retention indexes of n-alkanes the dependence was built, which allowed to calculate the retention times of 210 organic pollutants. Also this method was successfully applied for anal. of water from Almaty Lake-Settler “Sorbulak” and 68 main organic compounds were identified, including phenolic compounds,pesticides and polyaromatic hydrocarbons. In the experiment, the researchers used many compounds, for example, 3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4Quality Control of 3-Methyl-4-nitro-1H-pyrazole).
3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4) belongs to pyrazole derivatives. Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. The pyrazole ring is resistant to oxidation and reduction but the groups, such as alkyl and formyl attached to the ring, are oxidized to respective acids. Only electrolytic oxidation, ozonolysis, and a strong base cause ring opening.Quality Control of 3-Methyl-4-nitro-1H-pyrazole
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics