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The photocatalytic destruction of organic substances is an efficient method for the production of high-quality purified water for various applications. For photocatalytic purposes, titania is most widely studied due to its low cost, availability, untoxicity, and stable chemical structure. The combined application of a photocatalyst and hydrogen peroxide increases the degree of ecotoxicants destruction to CO2, H2O, and inorganic ions (mineralization) and shortens the reaction time to decrease the water treatment expenditures. Photocatalytic destruction kinetics was studied for a non-ionic surfactant, namely, octylphenol ethoxylate (Triton X-100) with hydrogen peroxide in an aqueous medium in reactors with immobilized TiO2. The conditions for achieving a high degree of mineralization of Triton X-100 (84–88% for 4–5 h at C0 = 50 mg/dm3) were established in the H2O2/TiO2/UV (λ = 254 nm) system in a reactor with TiO2 immobilized on a large-pore ceramic support alongside with its essential advantages as compared to the TiO2/UV system, where the maximum degree of mineralization of Triton X-100 was 2.5 times lower. The possibility of attaining a high degree of mineralization with hydrogen peroxide for Triton X-100 (up to 92% on TOC basis of 2 h) was demonstrated in a quartz reactor with a Degussa P-25 TiO2 film on its inner surface at the external irradiation mode (λ = 254 nm) without additional TiO2 powder. [ABSTRACT FROM AUTHOR]

The nematodoses are considered the most numerous group of cosmopolitan diseases among animal and human parasitoses. The representatives of the genus Trichuris attract special attention as pathogens of nematodoses. Their high fecundity, resistance to the influence of environmental factors and the ability to disperse create a serious ecological hazard and the risk of new outbreaks of infestation. The aim of the research was to establish the ovicidal efficiency of modern disinfectants on the embryogenesis of eggs of Trichuris skrjabini nematodes isolated from sheep. In laboratory conditions, two preparations were tested, DZPT-2 (mixture of glutaraldehyde, sodium dodecyl sulfate, essential oil) and Dixclor (mixture of sodium bisulfate, sodium chlorite, sodium percarbonate) at different concentrations and times of exposure. We established that DZPT-2 disinfectant showed a high level of ovicidal efficiency (97.5–100%) against T. skrjabini eggs at 4.5% concentration during exposure for 6–12 h and 5.0% concentration during exposure for 3–12 h. Dixclor showed a high level of ovicidal efficiency (100%) against Trichuris eggs at a concentration of 0.24% for exposures of 12 and 24 hours. Decreasing the concentration of disinfectants reduced the level of their ovicidal efficiency and led to the development of a greater number of viable eggs of T. skrjabini. Degenerative changes in the test cultures of T. skrjabini eggs caused by the tested disinfectants were characterized by the appearance and accumulation of air bubbles under the egg shell, the cessation of embryonic development at the bean-like embryo stage, loosening and resorption of the embryo inside the eggs, thinning and destruction of their shell, deformation of the eggs, and swelling of the egg plugs. Such destructive changes in eggs in experimental test cultures were also confirmed by the indicators of their morphometric parameters. Under the influence of DZPT-2 and Dixclor on the 54th day of cultivation, the length of the eggs was lower by 3.9%, and their width was greater by 4.8–5.1% compared to similar indicators in the control test culture. The obtained results allow one to recommend the tested disinfectants in defined and effective concentrations and exposures for effective control and prevention of trichurosis on livestock farms. [ABSTRACT FROM AUTHOR]

This article applies a systematic literature-based approach to select, analyze, and categorize publications appearing on public sector management (PSM) reforms in Eastern European (EE) and former Soviet Union (FSU) countries. Findings of the literature review reveal the complexity of reformation in the region and point to the multilayered character of the reform processes, including design of the reform content, implementation, and evaluation of achieved results. The analysis, also shows that the reforms’ results are uneven and somewhat controversial. This article contributes by systematizing literature on transforming PSM in EE and FSU countries; analyzing the trajectories of the dominant reforms and finding overlooked topics; providing avenues for future research; and by contextually covering twenty-eight countries that experienced economic transition and significant societal transformations.

Using sodium dodecylbenzenesulfonate the article showed high efficiency of photocatalytic system H2O2/TiO2/UV for deep destruction (~ 90% in terms of TOC) of anionic SAS in a aqueousmedium (C0 = 50 mg/dm3, pH0 5.9) in a reactor containing wide-porous ceramic block with immobilized TiO2 on its surface. The TiO2 film for a long time preserved a stable photocatalytic activity [ABSTRACT FROM AUTHOR]

Comparison of the efficiency of photocatalytic oxidation of aqueous solution of fulvic acids (TOC0—15.9-17.1 mg/dm3, pH0 6 ± 0.1) by oxygen of the air, hydrogen peroxide and ozone in a reactor containing a wide-porous ceramic block with immobilized TiO2 with the variation of the concentration of H2O2, feed rate of O3 and temperature showed advantages of photocatalytic ozonization and expediency of its use for deep destruction of natural organic substances in water. The maximum degree of destruction in photocatalytic systems O2/TiO2/UV, H2O2/TiO2/UV and O3/TiO2/UV constituted respectively 41, 73 and 90% for TOC for 5, 4 and 3 h. [ABSTRACT FROM AUTHOR]

We have investigated the impact of hydrogen peroxide on the change of the generalized indicators of water quality of the Dnieper River and model solutions of fulvic acids in UV radiation, ozonization, and O3/UV treatment. We confirmed its involvement in the oxidation process of organic impurities by all studied methods at the pH of the medium more than 7. However, the additions of 1–5 mg/dm3 of hydrogen peroxide inhibited the destruction of fulvic acid in a weakly acidic medium (pH 6.3) and reduced the mineralization degree of water impurities of the Dnieper River during O3/UV treatment and do note accelerate discoloration of the samples under investigation at the studied parameters of ozonization and O3/UV treatment. [ABSTRACT FROM AUTHOR]

We have studied the kinetics of the formation of hydrogen peroxide during UV-radiation, ozonization, and O3/UV treatment of water of the Dnieper River and model solutions of fulvic acids. We have also investigated decomposition of added hydrogen peroxide at the indicated methods of treating river and model waters and the impact of H2O2 on the concentration of dissolved ozone. [ABSTRACT FROM AUTHOR]

Variation of total toxicity of cationic SAS (surface-active substance) solutions in ozonization, UV radiation, and O3/UV treatment was evaluated by the change of bioluminescence intensity of the bacteria Vibrio fisheri B 7070 or Photobacterium phosphoreum B 7071 and chemiluminescence intensity in a reaction of luminole with H2O2 caused by exometabolites Daphnia magna. It has been shown that the least toxicity is characteristic of reaction blends after O2/UV treatment of cationic SAS solutions. [ABSTRACT FROM AUTHOR]