The limits of the pH buffering action (pHbuff) of YNHCH2SO3H – NH2CH2CH2OH –H2O (Y = H, CH3, HOCH2CH2, t-С4H9 and C6H5CH2) were determined and their buffer capacity (p) for monoethanolamine (MEA) was estimated in the temperature range 293–313 K. For systems with aminomethanesulfonic acid (AMSA), its N‑methyl, N‑hydroxyethyl (HEAMSA) and N‑benzyl (BzAMSA) derivatives, an increase in temperature leads to a decrease in the pH values of the lower limit of the buffering action of their solutions with monoethanolamine; in the case of N‑tert-butylaminomethanesulfonic acid (t-BuAMSA) – to an increase in the specified characteristic. An increase in temperature for systems with the most hydrophobic t-BuAMSA and BzAMSA (in comparison with other studied aminomethanesulfonic acids) leads to a decrease in the pH values of the upper limit of the buffer action. A decrease in the YNHCH2SO3H and NH2CH2CH2OH concentration leads to a shift in the boundaries of the pH of the buffering action to a more acidic region. The nature of the influence of the empirical function, combining their acid-base properties and lipophilicity (рKа + lgPow), on the concentration dependence of the buffer capacity according to MEA was revealed. It is shown that the buffering effect of the studied systems is due to the presence, in addition to the systems N‑alkylammoniummethanesulfonate – N‑alkylaminomethanesulfonate and 2-hydroxyethylammonium – monoethanolamine, ionic associates (pairs and triples). The position of the extrema on the graphical π=f(CMEA)/QYAMSA) dependencies for systems with hydrophilic AMSA and HEAMSA coincides with the position of the first minima on the differential titration curves dpH/dV = f(CMEA)/QYAMSA). Substitution of MEA to potassium aminomethanesulfonate leads to a shift in the pH buffering action to a more acidic region and increases the buffer capacity of the resulting systems.

The influence of hydrochloric, chloric, sulfuric and sulfurous acids (HCl, HClO4, H2SO4 and SO2×H2O, respectively) on protolytic equilibria in the system monoethanolamine (MEA) – tropeolin OOO (TrOOO) – water (CMEA = 0.1 M; pH = 1.0 ÷ 9.5) was studied by pH-metric, spectrophotometric and colorimetric methods. The acid-base behavior of the HOCH2CH2NH2 – TrOOO – H2O system was investigated at CTrOOO = 1,12 ×10-4 М, CMEA = 1,0×10-4 ÷ 1,0 М (pH = 8,25 ÷ 12,05), T = 293 K. TrOOO in this system exists in two tautomeric forms due to acid-base dissociation of the 4-OH group and associates formed by H-bonding with MEA molecules. There is a direct ratio between the pH values ​​of solutions and the total color difference (ΔE76), in contrast to the specific color difference (SCD). The difference in the behavior of the H2SO4 – HOCH2CH2NH2 – TrOOO – H2O system from the systems with HCl and HClO4 is due to the fact that the interaction of the first acid with MEA (8,0 £ pH) forms an ionic associate [HOCH2СH2NH3]2(SO4), which is more stable than ionic pairs [[HOCH2СH2NH3](HSO4), [HOCH2СH2NH3](ClO4), [HOCH2СH2NH3]Cl и [HOCH2СH2NH3](O3S-C­10H6-N=N-C6H4-SO3)[H3NCH2СH2OH]. Acid-base dissociation constants in systems significantly depend on the structure and physicochemical parameters of the mineral acid. In the electronic absorption spectra of the SO2 – MEA – TrOOO – H2O system (pH £ 7,5), there is a pronounced isobestic point at 415 nm, due to the dynamic equilibrium between ion-molecular forms. The coincidence of the maxima on the curves ΔE76 = f(pH) and SCD = f(pH) for the indicated system, in contrast to others studied in this work, was stated. The difference between the spectrophotometric and colorimetric behavior of the SO2 – MEA – TrOOO – H2O system from behavior of the systems with HCl, HClO4, and H2SO4 systems is due to the sulfur(IV)oxyanions with an azo indicator redox interaction.

The work summarizes the literature data on the hydration and chemisorption of toxic gases by polymeric sorption-active materials. The mechanisms of absorption by granular and fibrous ion-exchange and impregnated materials and the state of adsorbed water have been studied using various research methods (gravimetric, sorption-thermochemical, derivatographic, IR spectroscopic). The regularities of the hydration processes of granular strongly acidic sulfonic cationexchangers of the brands KU‑2 and KU‑23 (macroporous analogue), fibrous strongly acidic sulfonic cation- exchanger VION KS‑3, fibrous weakly acid carboxylic cation exchanger VION KN‑1 in various ionic forms are considered. Among the anion exchangers, the hydration of granular strongly basic anion- exchangers of the brand AV‑17, granular weakly basic anionexchangers of the brands AN‑25 (AN‑251 macroporous analogue) and ANKB‑35, fibrous strongly basic anion- exchangers of the brands FIBAN A‑6 and FIBAN A‑12, fibrous medium basic anion- exchangers of the brands CM‑2, fibrous weakly basic anion- exchangers of the brands CM-A1, VION AN‑1, VION AN‑3, FIBAN A‑5, FIBAN A‑11 and FIBAN AK‑22 are considered. It has been established that, by nature, the bond with the active centers of water is derided into a «bound» and a ordiner – «free». The first one is a monolayer and the nearest bonded with the ion of the ball; the other is the osmotic swelling water. It has been shown that for the effective absorption of most toxic gases and vapors (SO2, HCl, Cl2, SiF4, HF, NO2, NH3, аміни, COCl2, O3), it is necessary to have «free» water, which is not only a diffusion medium in which mass transfer proceeds, but also is a direct participant in chemisorption.

Acid-base interactions in the aminomethanesulfonic (N-alkylaminomethanesulfonic) acid–monoethanolamine–water (alkyl = methyl, 2-hydroxyethyl, tert-butyl, and benzyl) systems in the temperature range of 293–313 K were studied by pH, redox, and conductometric measurements. The ionic and molecular compositions of these solutions and formation constants of ion pairs and ion triples were calculated. Relative stability of the ionic associates was correlated with lipophilicity (log Pow) and strength (pKa) of the acids forming them.

An original procedure was proposed for the synthesis of a series of aminomethanesulfonic acids AlkNHCH(2)SO(3) (Alk = n-Bu, n-Hept, n-Oct, Bn) and N-tris(hydroxymethyl)methylammonium hydroxymethanesulfonate. The structure of the compounds synthesized was examined by elemental analysis, X-ray diffraction, IR spectroscopy, and mass spectrometry.

The influence of shielding gas component composition (pure Ar, pure CO2 and mixture Ar + CO2), mass rate of potassium additional agent and its injecting method on the ozone concentration in breathing zone are studied experimentally during the gas metal arc welding. Potassium injection into the arc zone was carried out in three different ways: via wetting the electrode wire or welding disk by aqueous solution of potassium carbonate, or by premix of the droplets of such a solution with shielding gas. Gas analyzer with electrochemical detector ELAN-O3was used for the measurement of ozone mass concentration in air with relative error 20%. The air sampler was located on the distance of 55 cm from arc. ItwasdetectedthatincreaseofСО2 content in shielding gas leads to decrease of ozone concentration down to 7 times, when pure СО2 is used. The increase of potassium additional agent injecting mass rate leads to decrease of ozone concentration in breathing zone for any method of potassium injection. The effect of potassium influence is different for the different injecting methods. Addition of potassium via wetting the electrode wire or workpiece by aqueous solution of potassium carbonate is more effective than via its premix with shielding gas. These results can be used for minimization of ozone hazard during the gas metal arc welding.

The pH-metric, conductometric and spectrophotometric study of the acid-base and electrochemical properties of methylammonium sulfamate aqueous solutions (1·10-4 – 1·10-2 М) in the temperature range 293 – 313 K has been done. The increase in pH and molar conductivity of the studied solutions during their storage over time is explained by the hydrolytic decomposition of sulfamate anions with the formation of sulfate anions and ammonium cations. In the concentration range (0,1 – 1,0)·10-3 М, the degree of hydrolysis of sulfamate anions depends slightly on the initial salt content and reaches 100%. A further increase in the salt content results a directly proportional decrease in the hydrolysis degree. Limit molar conductivity values by Shydlovsky extrapolation are calculated. The influence of the initial concentration of methylammonium sulfamate on the electrochemical properties of aqueous solutions was revealed. The experimental values of the limit molar electrical conductivity of aqueous solutions obtained with an extrapolation of Shidlovsky with an initial concentrations of methylammonium sulfate (1,0 – 10,0)·10-3 М increase with increasing temperature from 293 to 308 K. For solutions with a higher concentration, the values of the limit molar electrical conductivity is independent on temperature and l0 equals 206±19 Om-1·sm2·mol-1. The activation parameters of the conductivity of the investigated solutions at 293 – 313 K were obtained. A relative decrease in the mobility of hydrogen ions in the test solutions was observed, comparable to the valve of the mobility during the transfer along the H-bonds of water. The negative values of ΔS# indicate that the atoms in the activated complexes are located more «compactly» than in the original systems, that is, in the formation of the activated complexes the number of rotational and oscillatory degrees of freedom decreases. The compensatory effects in the activation parameters of the molar electrical conductivity of aqueous solutions of methylammonium sulfamate in the temperature range 293 – 313K are indicated.

The review is devoted to issues related to the selection of filter materials for the manufacturing of personal respiratory protection for the population, medical personnel during a pandemic. Biological aerosols, conditions of their formation and methods of capturing are characterized. The time of preservation of the virulent activity of microorganisms depends on their biological properties, air humidity and temperature, pH and salt composition of droplet aerosols, as well as physicochemical properties of sorbents. The main methods (chemical and biocatalytic modification, dessing and impregnation) of imparting antibacterial and virucidal properties to filter materials by biocides using, as well as the requirements for them are described. Because of the ongoing outbreak of a new coronavirus infection in the world, recognized by the WHO as a pandemic, it is of practical interest to provide promising bioprotection against pathogens of infectious diseases by including biocidal agents in filtering materials for respiratory purposes and identifying antibacterial and antiviral activity in existing chemisorption materials. Based on the analysis of the literature data, it was noted that the impregnated fibrous chemisorbents developed by the authors of the review based on biocides: N-containing organic bases (hexamethylenetetramine, ethanolamines); glycine; chelating agents (EDTA, phosphoric, hydroxyethylidenediphosphonic and citric acids); copper (II), nickel (II) and cobalt (II) complexes; acid-base indicators – should have additional antibacterial and antiviral functions. Chitosan, polyethyleneimine, ammonium quaternary bases, aminoalkanesulfonic acids, and dyes of various natures, including porphyrins, are promising for the creation of chemisorbents with biocidal properties.

The UV radiation intensity and mass concentration of ozone in air are studied experimentally in the gas metal arc welding. Effects of the shielding gas composition influence on UV radiation intensity, ozone concentration and welding fume formation are demonstrated. Addition of potassium via wetting the electrode wire or work-piece by aqueous solution of potassium carbonate and via its premix with shielding gas leads to decrease of UV radiation and ozone formation during arc welding. Discussions of the observed effects and theoretical model of radiation absorption are presented.

The principal possibility of increasing of the absorption capacity of impregnated fibrous chemisorbents (IFCS) acid gases based on nitrogen-containing organic bases by introducing into impregnating solutions of some additives such as sodium chloride, potassium iodide, ethylenediaminetetraacetic acid disodium salt (EDTA), glycine, sodium and potassium carbonates was investigated. Under static conditions using a vacuum sorption unit with McBen-Bakr quartz spring scales the hydrophilicity of fibrous chemisorbents of acid gases based on polyester synthetic fibers impregnated with polyethylenepolyamine containing as modifiers of potassium, such as potassium modifiers, such as promoters sodium and potassium carbonates, glycine and the disodium salt of ethylenediaminetetraacetic acid was studied. It is shown that the introduction of these additives leads to a sharp increase in the hydrophilicity of the samples, which creates the preconditions for further more efficient chemisorption of sulfur(IV) oxide. Within the framework of the Brunauer-Emmett-Teller theory of polymolecular sorption, water vapor sorption isotherms are analyzed, the values of the monolayer capacity and the values of the sorption heat of water molecules in the first layer are determined. Under static and dynamic conditions, chemisorption of sulfur oxide (IV) by dry and moistened samples of chemisorbents was studied. It is established that the process of SO2 chemisorption can occur only in the presence of «free» water formed after the formation of the monolayer. It is shown that the introduction of hydrophilized additives leads to a significant increase in the absorption capacity of sulfur(IV) oxide in both static and dynamic conditions. The obtained results are planned to use in the development of theoretical bases for the creation of functional sorption filtering materials for respiratory purposes.

Actual questions concerning the modern stage of development of catalysts for low-temperature carbon monoxide oxidation and their application in the personal respiratory protective equipment (PRPE) have been analyzed. Some approaches contributing to purposeful control of activity of Wacker type catalysts consisting of both palladium(II) and copper(II) salts and sorbents of different origin as well as their possible use in several environment protection devices have been considered. Despite some progress in the development of new catalysts for low-temperature CO oxidation, Hopcalite catalysts characterized by well-known disadvantages are as usual used in the series-produced PRPE. In our opinion, Au containing nanocatalysts and Pd(II)-Cu(II) catalysts based on modified natural sorbents such as Tripoli and clinoptilolite (Ukraine) are more perspective for this purpose. Available data concerning test conditions and activity parameters for some commercial catalysts at comparable CO inlet concentrations commonly used in PRPE, i.e. 130-300 mg/m3, were summarized. For comparison of their activity and evaluation of their applicability in PRPE, their air purifying ability (down to MPCCO in the air of work area) was used. It can be seen that the Au containing Nanoqold Cat (0.57 % Au/TiO2/AC) nanocatalyst demonstrates the highest activity providing the almost complete air purifying from CO: at CO inlet concentration of 625 mg/m3 and the residence time value of 0.04 s, the outlet concentrations are 1.25‑7.5 mg/m3 for 12 h. For NanAuCat (0.57 % Au/TiO2/AC) and AUROlite (1 % Au/TiO2), CO conversion values were equal to 48 % and 22 %, respectively, however, in this case the residence time value was lower by an order of magnitude. STC catalyst (Pt/SnO2) and AK-62 (2.4 % Pd/Al2O3) catalyst are less active than the above mentioned Au containing catalysts. The Wacker type catalysts are characterized by similar parameters however KNO-CO/MT is somewhat better showing the air purification down to MPC even at the residence time of 0.29 s. The residence time is a parameter determining the catalyst weight necessary to achieve a required CO conversion and dimensions of an applicable gas mask filter. Hopcalite catalysts used in the PRPE produced by the main companies over the world are the cause of large dimensions and weights of PRPE cartridges and canisters. Thus, low values of catalyst weights in “Platan” and “Suprovidnyk” devices, i.e. 50 g and 97 g, respectively, and high levels of protection from CO are their great advantages.

The dependencies of measured ultraviolet radiation intensity on the shielding gas composition, mass rate of potassium additional agent and its injecting method during the gas metal arc weldingare presented. The UV radiometer-dosimeter Tenzor-71 was used for radiation intensity determination. The UV radiation intensity was measured in three spectrum diapasons: UV-A with wavelengths 315-400 nm, UV-B with wavelengths 280-315 nm, and UV-C with wavelengths 200-280 nm. Potassium injection into the arc zone was carried out in three different ways: via wetting the electrode wire or welding disk by aqueous solution of potassium carbonate, or by premix of the droplets of such a solution with shielding gas. The increaseofСО2 content in shielding gas leads to decrease of UV radiation. The increase of potassium additional agent injecting mass rate also leads to decrease of UV radiation for any method of potassium injection. Theoretical model for UV radiation attenuation under potassium presence in shielding gas demonstrates well coincidence with experimental data: using the wetting of electrode wire provides the high local potassium concentration in the welding fume near arc column boundary and basic absorption of radiation occurs in the layer with thickness of 4 mm. The premix of potassium with shielding gas leads to its more uniform distribution in the gas layer around arc column with smaller concentration and provides weaker radiation absorption. These results can be used for minimization of UV radiation hazard during the gas metal arc welding.

Ionization mechanisms in welding fumes from gas metal arc welding are studied. Welding fume is a low-temperature thermal plasma with ultra-violet radiation as external ionization source, where ionization occurs via gas particles’ collisions and photoionization. The plasma cooling causes heterogeneous ion-induced nucleation, which provides large number of nuclei. Nucleus number density is much greater than equilibrium number density of charge carriers. Electrons are captured by nuclei. As a result, the dust–ion plasma is formed, in which electron number density is much less than ion and nucleus number densities and it can be neglected. The surface atom ionization and ion recombination becomes predominant processes. Calculation of the plasma component number densities are presented as their evolution during welding fume cooling.

The principal possibility of using the nickel (II) chloride complex with ethylenediamine (EDA) as a reagent for the creation of impregnated fibrous chemisorbents-amfolite (IFCS-A), which depending on the operating conditions can absorb acidic (SO2) and basic (NH3) gases, has been investigated. The sorption of water vapor by IFCS–Ni–EDA, obtained by impregnating a fibrous material with aqueous solutions of nickel (II) chloride complexes with EDA at different molar ratios Ni: N (1/k) was determined under static conditions, the nature of the effect of the pre-absorbed water on this process was stated. It was found the increasing the amount of EDA in combination with NiCl2 to decrease in the hydrophilicity of the obtained IFCS-A samples. Water adsorption isotherms are convex with respect to the P/Ps axis and are of type III according to C. Brunauer, L. Deming, U. Deming, Е. Teller classification. This type of isotherms is characteristic of the adsorption of gases and vapors by non-porous solids, and the weak adsorbent-adsorbate interaction causes a small amount of adsorption at low values of the relative vapor pressures of water.capacity and the heat of sorption of water molecules in the first layer has been determined. Under static and dynamic conditions the absorption of sulfur dioxide by the obtained IFCS–Ni–EDA samples was studied. It is shown the SO2 uptake process, going predominantly through the chemisorption mechanism, occurs only in the presence of «free» water formed with the formation of diamonium hydrosulfite (pyrosulfite) on the carrier fibers surface. It has been established the values of the SO2·H2O static chemisorption increase with increasing EDA content to k value in IFCS–Ni–EDA samples. Taking into account the literature data it is shown that the property of sulfur dioxide chemisorbing under static conditions of IFCS-A can be placed in the order: IFCS–Ni–EDA > IFCS–Ni–MEA > IFCS–Cu–PEPA. It is shown that the obtained IFCS–Ni–EDA can be used for absorption of acidic and basic gases at Ni : N = 1:1 ÷ 1:3. ratio. The protective action time of substantially IFCS–Ni–EDA (1.5 ÷ 2.0 times) exceeds the analogous values of existing IFCS-A based on complex compounds of copper (II) sulfate with ammonia and nickel (II) chloride with monoethanolamine and hexamethylenetetramine. IFCS–Ni–EDA is recommended for use in equipping of respiratory protection devices – lightweight gas-dust respirators.

Formation of particles in a fume plasma obtained from the gas metal arc welding is investigated by the numerical modeling of the plasma evolution. The model of welding fume plasma evolution includes the following processes: vapor emission from the arc zone and mixing with a shielding gas, plasma formation, nucleation, nucleus growth via the material condensation and coalescence, solidification of liquid droplets into primary particles, and coagulation of primary particles into inhalable particles in the breathing zone. The computed results are compared with experimental data on the specific surface area, chemical composition, and dependence of the particle sizes on the shielding gas temperature.

Ionization balance and nucleation in the plasma, which is formed in welding fumes from gas metal arc welding, are studied. It is demonstrated, that large number of nuclei causes the replace of volume thermal ionization by ionization via nucleus surface. The equation for change in Gibbs free energy during nucleation should be also replaced. Absence of the easy-ionizable additional agent forces the iron atoms to execute both functions: a source of ionization and a source of nucleation. As a result nucleation occurs during short time, because condensable material promptly ends.

Aminomethanesulfonic acid (I) and its N-methyl- (II), N-(2-hydroxy)ethyl- (III), N-(tert-butyl)- (IV), N-benzyl- (V), and 4-(N-phenylaminomethyl)phenyl- (VI) derivatives (V and VI not previously reported) were synthesized and characterized by elemental analysis and IR and mass spectroscopy. The in vitro antioxidant activities of aminomethanesulfonic acids I-VI were found to be comparatively weak. Compounds IV and V suppressed statistically significantly reproduction of influenza virus strains A/Hong Kong/1/68 (H3N2) and A/PR/8/34 (H1N1) in chorioallantoic membrane tissue culture.

Work is sanctified to research of adsorption descriptions and basic physical and chemical properties and chemical distribution of standards of the ground sedimentations (GS) selected from a superficial layer (0-18 cm) in north part of aquatorium of the Kuyalnik estuary. The sorption of water and methanol vapor, ammonia and sulfur dioxide was determined in the static conditions. Sorption isotherms have been analyzed according to Brunauer-Emmett-Teller theory of polymolecular sorption, the monolayer capacity and the heat of sorption of water molecules and methanol in the first layer have been determined. The essential difference between the values of the specific surface, calculated by different methods (Brunauer-Emmett-Teller theory, Kiselev). The differences in their values are is natural, as for the calculations data are used to measure the sorption of water vapor at different sites of isotherms (for BET - the area at p/ps = 0,01±0,4; Kiselyov at p/ps = 0,55±0,98). Under static conditions the absorption of sulfur dioxide and the ammonia by bottom sediments samples was studied. It is shown the SO2 uptake process, flogoing predominantly through the chemisorption mechanism, occurs only in the presence of «free» water formed after the formation of the monolayer. The maximum sorption capacity on dry samples is 2,6 mg/g. The limiting ammonia sorption capacity (19,1 mg/g at P = 13,3 kPa), unlike sulfur dioxide, in our view, is mainly determined by their organic component, namely the presence in it of humic acids having polyfunctional groups, such as phenolic, hydroxyl groups, carboxylic acid groups that are capable of adsorbing, absorbing and selectively extracting various organic and inorganic substances. The dispersion, organomineral composition, biological, bactericidal activity and sorption characteristics of the samples of bottom sediments (peloids) Kuyalnik estuary in relation to a number of markers of different nature (water vapor, methanol, ammonia, sulfur dioxide) show prospects for use as a cheap natural raw material to expand the range of sorbents for environmental purposes, entero - and vulnerosorbtion (application of sorbents) for medicine, cosmetology.

Samples of natural bentonite and clinoptilolite modified with copper(II), iron(III), and palladium(II) were characterized by both X-ray phase and the Fourier transform infrared spectral methods. The activity of monometallic compositions MiLj/S(M = Co(II),Fe(III), and Pd(II); L = NO3-, Cl-, and SO42-; S = N-CLI or N-Bent) in the reaction with sulfur dioxide was found to depend on the nature of both a metal ion and a support. For bimetallic compositions Cu(II) Fe(III) and Cu(II) Pd(II) based on the natural aluminosilicates, a certain synergism in the action of metals forming these pairs towards the reaction of sulfur dioxide oxidation with oxygen was determined.