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The adsorption kinetics of Mn2+ ions by AG-3 activated carbon granules is investigated. It is found that the pseudo–first-order Lagergren kinetic model describes manganese adsorption for only 300 min. By contrast, the pseudo–second-order model proposed by Ho and McKay describes the entire process. The role played by diffusion through the sorbent pores in limiting the rate of Mn2+ ion extraction is estimated by the Weber–Morris method, on the basis of the isotherms of Mn2+ ion adsorption by activated carbon granules. With a high degree of correlation (R2 ~ 0.96–0.99), the equilibrium of Mn2+ ion adsorption is described by the Langmuir equation. The limiting adsorption capacity of a sorbent monolayer is calculated at various temperatures. When using the adsorptional equilibrium temperature, the thermodynamic parameters of the process are determined. The sorptional extraction of metal ions is greater at higher temperatures. The adsorption of metal ions at the carbon surface is described by means of IR spectroscopic data. [ABSTRACT FROM AUTHOR]

In the treatment of open-pit wastewater at mining enterprises, phenol is adsorbed on carbon sorbents, in equilibrium. The influence of minerals in the wastewater on this process is studied. At low phenol concentrations, inorganic compounds impede its adsorption. Iron and manganese ions have a particularly strong influence on phenol extraction. The basic adsorption parameters are calculated using the Freundlich and Dubinin–Astakhov equations. [ABSTRACT FROM AUTHOR]

Means of removing sulfate ions from mine wastewater are analyzed. Their advantages and disadvantages are weighed. A sound basis is proposed for selecting the best treatment technology. A system based on reverse osmosis is developed. [ABSTRACT FROM AUTHOR]

The endosymbiotic bacteria Wolbachia are widespread in natural populations of Drosophila melanogaster, which is a cosmopolitan and synanthropic species. Various aspects of Wolbachia infection are studied in many arthropod species, including fruit flies. However, the influence of climatic factors on the level of Wolbachia infection in natural populations of fruit flies has not been studied in detail. The influence of mean temperature, precipitation, and potential evaporation was investigated on Wolbachia infection rates in ten D. melanogaster populations (collected in Europe) and newly obtained estimates were combined with the data from other studies for different continents and for different climatic zones (280 populations, 10 806 isofemale lines). The effect of climatic factors on the infection frequency was revealed. The highest infection rates are observed in the mean annual temperature range of 20–25°C, which corresponds to fly rearing conditions in the laboratory. The clinal distribution of Wolbachia infection rates in the Eurasian fruit fly populations was described. Logistic regression models showed that climatic factors have a stronger impact on bacterial infection rates within climatic zones rather than continents. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.3103/S1068364X24010046 [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.3103/S1068364X24010022 [ABSTRACT FROM AUTHOR]

The partial oxidation of unsaturated aldehydes such as acrolein and methacrolein to the corresponding carboxylic acids is of big importance for the chemical industry. The heart of these production plants is the oxidation catalyst. Acrylic acid is produced via the selective oxidation of acrolein on Mo/V/W mixed oxides with an excellent catalytic performance (S > 90 %, X > 95 %, life time >3 a). Under the same conditions the conversion of methacrolein to methacrylic acid has a poor catalytic performance (S < 35 %, X ≈ 40 %). To this day the reason for this is unclear. Hence, for the partial oxidation of methacrolein a heteropoly acid catalyst is used with a good performance (S ≈ 88 %, X ≈ 62 %), but unfortunately the lifetime is unsatisfactory (<1 a). Therefore, we have studied the gas and surface mechanism of the partial oxidation of acrolein to acrylic acid on mixed oxides with the help of in-situ experiments. The learning outcome of this study will help us to find a rational way to come up with a new catalytic system for the unsatisfactory partial oxidation of methacrolein to methacrylic acid and are summarised in a new extended mechanism. [ABSTRACT FROM AUTHOR]

Peritoneal hydatidosis secondary to liver hydatid disease is not uncommon but peritoneal hydatidosis herniating to the inguinal canal is rare, with fewer than five cases reported in the literature. We describe a 54-year-old man who presented with a progressively enlarging soft, cystic swelling in the right inguinal region. Clinical examination suggestive of irreducible right inguinal hernia and ultrasonography revealed it to be a cystic swelling within the hernial sac. The swelling was excised en bloc and open mesh hernioplasty was performed. Cyst biopsy revealed hydatid disease; hence, the patient was put on adjunctive albendazole chemotherapy for 3 months. [ABSTRACT FROM AUTHOR]