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The article presents the results of comparative studies of the rheological properties of the ceramic polymer blend of polylactide (PLA) filled with 50 %vol alumina to evaluate the possibility of obtaining extruded filament for 3D printing.

Electromagnetically induced gratings (EIG) are created by standing-wave laser field in resonant media. Such gratings can be also created by few-cycle electromagnetic pulses counter-propagating in the medium via coherent Rabi oscillations of atomic inversion. In this case, instantaneous cross-section of the pulses in the medium is not necessary for grating formation. In this paper, we revise our recent results in study of such grating formation and their control by few-cycle pulses coherently propagating in a resonant medium. We demonstrate the grating formation and their control in three-level medium excited by three subcycle THz pulses.

A kinetic model that describes the evolution of residual stress in thin polycrystalline films during bombardment by ions with energies below the sputtering threshold is presented. The mechanisms responsible for the change in stress are the generation of point defects on the surface and their redistribution over the film thickness along grain boundaries. The presented model was used to explain the experimental data on the change in stress in thin Cr films after treatment in Ar plasma of low-pressure RF induction discharge with ion energy of 15-30 eV.

Various approaches are used to improve baker’s yeast technological properties of and final products quality. Because of low-frequency ultrasound does not have a destructive effect on yeast cells, the aim of our research is to test a new method of improving the technological properties of baker’s yeast using low-frequency ultrasonic cavitation. The object of the study was active dried baker’s yeast Saf-levure (France). All experimental and control samples were processed in a “Grad” ultrasonic bath (Russia) with different intensities and processing times at a frequency of 35 kHz. It was shown that precure of baker’s yeast with ultrasound at a frequency of 35 kHz, an intensity of 0.5-1 W/cm2 and an exposure of 1 and 3 minutes redound to improving the baker’s yeast technological properties: the yeast specific growth rate increases by 1.8–2.7 times, and yeast rising power - by 1.2–1.6 times. At the same time, baked with ultrasonic-treated yeast bread has significantly improved physicochemical and organoleptic characteristics compared to traditional bread. Acidity and humidity of the bread crumb decreased by 1.2 and 1.3 times and porosity increased by 1.6-2.5 times with an increasing the time and intensity of the sonication. With increasing of sonication time and intensity, the bread crust became golden brown, the color of the crumb became lighter, and the loaf shape fluffier. The best results are obtained after precure of baker’s yeast suspension with ultrasound at a frequency of 35 kHz, an intensity of 1 W/cm2 and an exposure of 3 minutes.

In the food industry, when processing fruits and vegetables, heat treatment is used. Most often, the pretreatment processing of plant materials is carried out with steam or water, as a result of which there is a loss of nutrients valuable for the human body, including antioxidants. The article proves the advantage of using microwave heating as a preliminary heat treatment of apple and beet refuse in order to increase nutritional value by increasing the content of water-soluble antioxidants in them. Thus, the content of vitamin C increases by 1.32 - 1.57 times, flavonoids by 1.77 - 2.01 times.

Currently, the mechanisms of influence of microwave and infrared energy on the nutritional value of raw materials and food products are not fully understood. At the same time, the main task of the food industry is the maximum possible preservation of the healthy properties of raw materials during its processing, including using of physical methods. The authors investigated the possibility of using microwave and infrared heating in the production of dried beet refuse. The optimal parameters of microwave processing of beet refuse were established, at which the maximum increasing of the total antioxidants content is observed: electric power - 800 W, time - 160 sec, specific work - 640 W / g · sec, heating temperature of refuse - 92 ° C. The intensification of the process of beet refuse infrared drying with the lowest loss of antioxidants is provided at a temperature of 60-65°C and a drying time of 3 hours 25 minutes.

In this paper, we revise our recent advances in study of high-efficient methods of sub cycle THz pulse generation and control of their wave shape. These methods are based on coherent control of low frequency oscillations in nonlinear medium excited by infrared femtosecond pulses. Our results showed the possibility of sub – and few-cycle pulse formation of controllable wave shapes: half-cycle, rectangular and triangular and single-cycle ones in THz, XUV and optical ranges.

Experiments on the Fourier transform spectrometry of Nafion, a water-swollen polymeric membrane, are described. The transmittance spectra of liquid samples and Nafion, soaked in these samples, were examined, depending on the deuterium content in water within the spectral range 1.8 - 2.15 μm. The experiments were carried out according to two protocols: with the first protocol we studied the dynamics of Nafion swelling in H2O + D2O mixtures for the deuterium concentrations 3 < C < 104 ppm, and with the second protocol we studied the dynamics of swelling in pure heavy water (C = 106 ppm). For liquid mixtures in the concentration range 3 < C < 104 ppm, the transmittance spectra are the same, but for Nafion soaked in these fluids, the corresponding spectra are different. It is shown that, in the range of deuterium contents C = 90 - 500 ppm, the behavior of transmittance of the polymer membrane is non-monotonic. In experiments with the second protocol, the dynamics of diffusion replacement of residual water, which is always present in the bulk of the polymer membrane inside closed cavities (i.e., without access to atmospheric air), was studied.

This paper is devoted to the investigation of relative magnetoresistance MR in semiconductor polycrystalline materials: CuInAsS3, CuInAsSe3, CuInS2 and CuInSe2 under high pressures up to 50 GPa and at a constant transverse magnetic field. The pressure ranges of significant changes in the behavior of electrical resistance and magnetoresistance were identified for these materials. The features in the properties of CuInSe2, CuInS2 and CuInAsSe3 at these pressures are consistent with the data on the baric structural phase transitions in these materials. In the case of CuInAsS3 and CuInAsSe3 a shift of pressure intervals in which phase transitions can occur is observed that can be explained by an effect of chemical compression due to the changing the atom radii of the chemical elements forming the compounds.

We consider theoretically recently proposed a new possibility of creation, erasing and ultrafast control of population density grating. Such grating can be created in resonant medium when ultrashort pulses with duration smaller than relaxation times in the resonant medium (coherent light matter interactions) propagate without overlapping in this medium. Possible applications in the ultrafast optics such as optical switcher and laser beam deflector are discussed.

The influence of ion-plasma treatment on residual stress in the microcantilever is investigated. The ability of treatment with energy below the sputtering threshold to affect the mechanical stress is shown. It is also demonstrated that a preliminary vacuum thermal annealing of samples reduces the influence of ion bombardment on the residual stress. With the increase of the annealing temperature the effect of ion bombardment disappears.

We report on our study of electrical resistance of double-walled carbon nanotubes (DWCNTs) at pressure up to 30 GPa. High pressure has been generated in the diamond anvil cell with conductive synthetic diamonds. We detect a decrease in DWCNTs resistance with increasing pressure and correlate the results with the corresponding structural transformations. Analysis of the DWNTs Raman spectra confirms the irreversible structural changes.