Development of a Method for Predicting the Recurrence of States of Atmospheric Air Pollution Concentration in Industrial Cities

This paper reports the method developed for predicting the recurrence of states related to air pollution at industrial cities based on the modified window measure. The new scientific result implies that dangerous states of the urban air pollution should be identified and predicted based not on the prediction of the concentration of pollution as it is, but based on forecasting the recurrence of states of the concentration of atmospheric air pollutions. The proposed prediction method makes it possible to operatively forecast not only the clear but also hidden dangerous states of air pollution at industrial cities. This provides for an overall improvement in the effectiveness of interventions to prevent hazardous contamination of the atmosphere and the environment. The results of experimental testing indicate the feasibility of the proposed method. It was established that in the test interval of monitoring (between counts 12‒36) there were sharp characteristic changes in the predicted measure for the recurrence of state. It is noted that such changes are the predictors of hidden events involving hazardous air pollution at industrial cities. It was experimentally found that a more accurate forecast is ensured for the forecast horizon d=1 (6 hours). It is shown that in the considered case, in order to ensure the reliability of forecasting laminar states in the contaminated atmosphere, the smoothing parameter to be selected should not be less than 0.8. It is noted that in order to predict dangerous states of the atmosphere pollution based on the dynamics in the prediction of a state recurrence measure, there is no need in the information about meteorological conditions at the time of forecasting and in the future. This is the main distinguishing feature and advantage of the proposed prediction method. A given method for RS forecasting proves to be invariant to urban configuration, the types of stationary and mobile pollution sources, as well as meteorological condition

Study of the Free Surface Energy of Epoxy Composites Using an Automated Measurement System

Results of development of the automated measurement system (AMS) for determining contact wetting angles and calculations of components of free surface energy (FSE) of solid surfaces by the Van Oss-Chaudhury-Good method were presented. It was shown that AMS allows for calculations based on experimental measurement of geometrical parameters of a lying drop on the surface and energy characteristics of test fluids. It was found that the measured contact wetting angles and calculated values of FSE components of surfaces of epoxy polymer composites, steel and glass are adequate and reliable.Based on the conducted measurements and calculations, relationship between FSE, the structure and properties of epoxy polymer composites, filled with rutile, was established. In the course of research that was conducted using AMS, it was found that at an increase of the content of rutile, total FSE (γs), dispersive (γd) and acidic-basic (γab) components of composites increase. Dependences γs and γd on the filler's content are extreme in character, and γab increases and does not change at a subsequent increase in the amount of rutile. The influence of rutile is represented most vividly by dependences of the acidic (γa) and basic (γb) components, into which the polar (acidic-basic) FSE component γab is disintegrated. It was found that structural transformations are associated with the acidic-basic mechanism of intermolecular and inter-phase interactions in epoxy composition

A Research of Chemical Nature and Surface Properties of Plant Disperse Fillers

Chemical nature and surface properties of plant disperse fillers are investigated: buckwheat (BH) and oat (OH) husk, wood (WF) and conifer flour (CF). Using IR spectroscopy, it was found that oxygen-containing atomic groups –OH, –C–O–, –C=O prevail in the filler components. It was found that a hydroxyl-hydrate layer of functional groups is present on the surface of air-dry fillers. By potentiometric titration of aqueous suspensions using the Parks–Bobyrenko method, it was determined that all fillers are of the «polyfunctional solid» type. It is shown that the hydroxyl-hydrate surface layer consists of functional groups with similar values of acid-base characteristics. Functional groups of acidic nature were additionally found on the surface of the fillers: groups with pKa≈4.37−5.66 on the BH surface, groups with pKa≈4.49−4.90 on the CF surface and groups with pKa≈3.91−4.30 on the WF surface. As a result of potentiometric titration, it was shown that the surface acidity of the fillers decreases in the WF>CF>BH>ОH series, which coincides with the one in which the total cellulose and lignin content decreases, and the resistance of fillers to thermal-oxidative breakdown increases. It was found that the rate of hydrolytic processes in aqueous suspensions at the interface decreases in the ОH>CF>BH>WF series and inversely depends on the concentration of functional groups on the surface of the fillers, and also that the change in the rate of hydrolytic processes at the interface depending on the content of fillers is described by step functions. It is revealed that for the effective use of the studied disperse waste in composite materials and as adsorbents for the extraction of pollutants, dispersion media with the following ranges of the hydrogen index are required: for BH − pH>4.4; OH − pH>6.4; WF − pH>3.9; CF − pH>4.5. The results obtained make it possible to predict and control acid-base interfacial interactions, as well as reasonably approach the development of new effective technologie