The SiOx barrier nanocoatings have been prepared on selected polymer matrices to increase their resistance against permeation of toxic substances. The aim has been to find out whether the method of vacuum plasma deposition of SiOx barrier nanocoatings on a polyethylene terephthalate (PET) foil used by Aluminium Company of Canada (ALCAN) company (ALCAN Packaging Kreuzlingen AG (SA/Ltd., Kreuzlingen, Switzerland) within the production of CERAMIS® packaging materials with barrier properties can also be used to increase the resistance of foils from other polymers against the permeation of organic solvents and other toxic liquids. The scanning electron microscopy (SEM) microstructure of SiOx nanocoatings prepared by thermal deposition from SiO in vacuum by the Plasma Assisted Physical Vapour Deposition (PA-PVD) method or vacuum deposition of hexamethyldisiloxane (HMDSO) by the Plasma-enhanced chemical vapour deposition (PECVD) method have been studied. The microstructure and behavior of samples when exposed to a liquid test substance in relation to the barrier properties is described.

The present study was conducted in order to evaluate the efficiency of personal body microclimate cooling systems based on a phase change materials and its effects on physiological strain in soldiers during exertional heat stress in hot environment. The results are obtained in the experiment conducted in the climatic chamber in the Institute of Hygiene, Military Medical Academy in Belgrade. Ten male soldiers were voluntarily subjected to exertional heat stress tests consisted of walking on treadmill (5.5 km/h) in hot conditions (40°C) in climatic chamber. The subjects performed first test while wearing a field camouflage uniform without any cooling system (CONTROL group) and in second test they used additional microclimate cooling system with paraffin wax consist of n-hexadecane (C 16 H 34 ), in a form of cooling packs (COOL group). As indicators of thermal strain, mean skin (T sk ) and tympanic (T ty ) temperature were determined. Simultaneously, thermal effects of phase change materials were measured by thermal imaging camera. The exercise in hot conditions induced a physiological response to heat stress, manifested through increased body core and skin temperatures. The results confirmed that the cooling vest worn over the field uniform was able to attenuate the physiological strain during exercise, compared to the identical exposure in the "control" group. The results of thermal imaging also indicate that heat generated inside the body is the main factor that will affect the phase change material melting time.

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Using a body cooling system based on PCM in the form of vest under NBC protective clothes during physical activity in hot conditions, reduces sweating and alleviates heat stress manifested by increased core and skin temperatures and heart rate values. These effects directly improve heat tolerance, hydration state, decrease in the risk of heat illness, and extends the duration of soldiers' exposure to extreme conditions.

Real systems approach the ideal by solving technical and physical contradictions. Optimization of system engineering (SE) is achieved when the problem is solved at the level of technical contradiction. When the problem is solved at the level of physical contradiction, the idealization of SE is achieved. Two possible ways of achieving ideality are described in this paper. The expansion process flows at the level of SE (i.e., idealization of another type), and the reduction process flows at the subsystem level (i.e., idealization of the first type). A procedure of mathematical modeling is presented for determining the level of ideality as a criterion for filtering protective suit (FPS) effectiveness, which can be used as a standard for determining the ideality of any SE.