Aerogels with a density of 4.2−22.8 kg/m 3 were obtained from bacterial cellulose synthesized under static and dynamic cultivation conditions on a molasses medium. The strength properties and porous structure of the aerogels strongly depended on their density. With an aerogel density of 22.8 kg/m 3 , the modulus of elasticity at 80% compression of the sample was 0.1 MPa. The decrease in the density of aerogels led to an increase in the pore sizes ranging from 20 to 1000 μm and a decrease in the modulus of elasticity. These characteristics were more pronounced in aerogels obtained from bacterial cellulose under static cultivation conditions. The aerogels had a low coefficient of thermal conductivity (0.0257 W m −1 °C−1 ), which is comparable to the thermal conductivity of air, and moderate thermal stability because the degradation processes of the aerogels began at 237 °C. The aerogels obtained from bacterial cellulose had high sound absorption coefficients in the frequency range of 200−5000 Hz, which makes it possible to use the aerogels as heat-and sound-insulating materials.

In the modern cosmopolitan world, flexible sensors are essential components of the intelligence and information industry. We analyze the latest advancement and improvement of research into the pliable or flexible material based carbon nanotubes sensors. Linear cables kind and flexible materials based on carbon nanotubes are used for developing intelligent flexible equipment for applications in electronics, artificial skin, biomedicine, robotics, energy, healthcare products and most importantly for sensing hazardous gases. In the present analysis, we outlined the development of flexible sensing platforms based on carbon nanotubes and polymers for sensing various environmental polluting gases such as CO2, H2S and NH3. In addition, we also discussed the device structure, materials and fabrication techniques for developing flexible sensors. The conclusion exhibits the viewpoint and the challenges faced by the materials and methods of the flexible sensor.

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During the last several years, new multi- and single-layered archaeological sites, in which the most ancient Neolithic pottery in the Eastern Europe had been found, were excavated in the region of Lower Volga. Animal bones and organic materials were sampled from these sites for radiocarbon (14C) dating and diet investigations. The evidence from these studies suggests that the first domestic animals in the Lower Volga region appeared in the Cis-Caspian culture of the Early Eneolithic. Lipid analysis of food crusts from pottery allowed the cooked food to be characterized. The detailed chronology from Neolithic (6500–5400 cal BC) to Eneolithic (5300–4700 cal BC) cultures, as well as the diet of these ancient people, were reconstructed.