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1.
Eurasia Soil Sci ; 55(2): 235-241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38624946

RESUMO

The results of a laboratory experiment modeling the effect of kerosene contamination on the cellulolytic activity of microbiocenosis of the Albic Retisol (Kaluga oblast, Russia) and Arenosol (Kyzylorda oblast, Republic of Kazakhstan) humus horizons are described. Cellulolytic activity is assessed according to the rate of weight loss in linen cloth fragments during the incubation for 0-3, 3-7, and 7-13 months. The intensity of cellulolytic activity in the unpolluted Albic Retisol is higher as compared with the Arenosol, which is determined by low acidity and an elevated content of organic matter and nutrients. The soil pollution with kerosene to 10 g/kg causes a reversible change in cellulolytic activity of both Albic Retisol and Arenosol (Aridic). A high load of kerosene (≥25 g/kg) inhibits cellulolytic activity in both soils over 13 months of observation. Supplementary Information: The online version contains supplementary material available at 10.1134/S1064229322020119.Fig. S1. Cellulolytic activity of soils in a laboratory experiment: (a) initial state of linen tissue (test object) and (b) linen tissue after three months of incubation. Table S1. Properties of soil humus horizons.Table S2. Initial water content in the studied soil samples with due account for the added kerosene.Table S3. Cellulolytic activity in soils grouped according to kerosene load (rate of mass loss, mg/g soil per day.Table S4. Significance of differences between cellulolytic activities of contaminated soil samples relative control samples according to the Mann-Whitney U-test. Table S5. Kerosene content in the studied soil samples at the end of the experiment, % of the initial content.

2.
Environ Pollut ; 268(Pt A): 115711, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33120344

RESUMO

In this paper, we briefly described the ecological consequences of six space rocket accidents launched from the Baikonur Cosmodrome between 1999 and 2018 and focused on an assessment of efficiency of soil remediation following the accidental crash of launch vehicle Proton-M on July 2, 2013, which resulted in the severest environmental impact in the modern Russian space industry. On the day after the accident, the content of carcinogenic unsymmetrical dimethylhydrazine and nitrosodimethylamine, as well as nitrate in soils of the crash site exceeded their maximal permissible concentrations by 8900, 6100 and 85 times, respectively. Mitigation measures included soil detoxication by a solution of 10% H2O2 and 1% iron complexonate, soil excavation and ploughing. Two years later (in April 2015), both unsymmetrical dimethylhydrazine and nitrosodimethylamine concentrations were below 0.05 mg/kg and nitrate concentration did not exceed 3.9 g/kg. As compared to background sites, soils of the crash site had significantly (P-value<0.05) lower values of pH and the content of total organic carbon, basicity from soda and carbonates and higher total nitrogen and soluble salt contents. Soil microbial communities were the most vulnerable component of the disturbed arid ecosystems, as their suppressed condition was indicated by a low biochemical oxygen demand and a very low cellulase activity.


Assuntos
Poluentes do Solo , Acidentes , Ecossistema , Peróxido de Hidrogênio , Cazaquistão , Federação Russa , Solo , Poluentes do Solo/análise
3.
Sci Total Environ ; 709: 136072, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31887495

RESUMO

In this paper, we assessed snow pollution by nitrogen-containing substances including rocket propellants - UDMH (unsymmetrical dimethylhydrazine, (СН3)2NNH2) and NT (nitrogen tetroxide, N2O4) - and their transformation products (NDMA (nitrosodimethylamine, (CH3)2NNO), NO3-, NO2- and NH4+) within the falling regions (FRs) of the first and second stages of Proton-M rockets launched from the Baikonur Cosmodrome. At the first stage FR in Central Kazakhstan, snow with a pH range from 1.7 to 9.0 was contaminated by N-containing substances (maximal value in g/L): UDMH - 0.27, NDMA - 0.04, NO3- - 19, NH4+ - 0.04 and NO2- - 0.13. The first stage landing resulted in snow contamination by soil dust particles and N-containing substances at a rate of 13 g/m2 and 82 mg/m2/day, respectively. The maximal permissible addition (MPA) for UDMH, NDMA and NO3- to the 0-5 cm layer of soil was estimated at 0.06, 0.006 and 70.2 mg/m2, respectively. At the second stage FR in the NE Altai, substances released by space transportation were absent and the concentration of NO3- and NH4+ corresponded to the natural background level. The index of contamination (IC) was used for characterizing the degree of snow contamination by N-containing substances. A simulation model was developed for analysing the dependence of snow contamination by rocket propellant components on the weather parameters.

4.
Phys Chem Chem Phys ; 18(13): 9281-94, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26976747

RESUMO

Eight adamantane derivatives of sulfonamides were synthesized and characterized. Temperature dependencies of saturation vapor pressure were obtained using the transpiration method and thermodynamic functions of the sublimation processes were calculated. Solubility values of the selected compounds in buffer (pH 7.4), 1-octanol and 1-hexane were determined at different temperatures using the isothermal saturation method. Thermophysical characteristics of fusion processes (melting points and fusion enthalpies) of the substances were studied using the DSC method. Transfer processes from buffer to 1-octanol, from buffer to 1-hexane and 1-hexane to 1-octanol were analyzed. The impact of the molecules' structural modification on sublimation, solubility and solvation/hydration processes in the solvents was studied. Correlation equations connecting the thermodynamic functions with physicochemical descriptors were obtained.


Assuntos
Adamantano/química , Sulfonamidas/química , Varredura Diferencial de Calorimetria , Solubilidade , Temperatura
5.
J Chromatogr A ; 1215(1-2): 161-7, 2008 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-19026424

RESUMO

Thermodynamic characteristics of infinitely diluted solutions of n-alkanes and n-alcohols in the columnar and isotropic phases of poly(propyleneimine) dendrimers, generations 1-3 (G1-G3), have been investigated by inverse gas chromatography (IGC). Effects of the dendrimer structure, the chemical nature and molecular size of the non-mesogenes on the ability to get dissolved in the liquid crystalline phases are discussed. The compatibility of the low-molecular compounds with the anisotropic phases is stated to increase with generation G.


Assuntos
Cromatografia Gasosa/métodos , Dendrímeros/química , Polipropilenos/química , Soluções , Termodinâmica
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