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This paper presents the results of an experimental investigation of the diffusion combustion scenario of a round hydrogen microjet flowing from a cylindrical thin-walled micronozzle with a diameter of 200 μm when ignited near and at any distance from the nozzle exit. A review of the literature on the research topic is presented and a comparison is performed in dimensionless parameters based on the Reynolds number. It has been established that stabilization of the torch during the expiration of a round microjet of hydrogen is associated with heating of the nozzle by the laminar region of the flame. A hysteresis of the process of diffusion combustion of round hydrogen microjets was discovered depending on the region of ignition of the microjet (laminar or turbulent region of the torch) and on changes in the jet velocity.

Controlling the shape of the interfacial boundary is an important technological task. The effect of rotation velocity modulation on the interface between light viscous and denser low viscosity fluid in a rotating horizontal cylinder is studied experimentally. Liquids are characterized by a high contrast of viscosities, these are glycerin and a low-viscosity (denser) fluorinert FC-40. Glycerin is stained with rhodamine, which makes it possible to study the shape of the interface by photo registration with high accuracy when illuminating liquids with a green laser, which causes rhodamine fluorescence. Experiments are carried out in the centrifuged state of liquids when the gravity field has no effect while varying the rotation speed, as well as the amplitude and frequency of librations. It is found that librations qualitatively change the shape of the interface near the ends of the cavity without affecting the cylindrical interface in the middle cavity part. It is shown that this is due to different "viscous" interactions of liquids with the ends of the oscillating cavity, as a result of which the interface near the ends performs radial oscillations with a frequency of librations, and the latter leads to an averaged radial displacement of the wetting boundary of the ends, which increases with the modulation amplitude. At certain amplitudes, the contact line reaches the outer boundary of the cavity. It is shown that the dynamic equilibrium of the interface between liquids of different densities is determined by the averaged interaction of liquids of different viscosity with the oscillating ends.

Experimental data on diffusion combustion of plane hydrogen microjets emanating from a slotted micronozzle at subsonic and supersonic velocities are reported. Four scenarios of diffusion combustion of the hydrogen microjets are presented. As is found, the stabilization of subsonic combustion of the hydrogen microjet is related to the origination of a “bottle-neck” configuration of flame while in supersonic conditions the flow pattern is dominated by supersonic cells. Hysteresis of the diffusion combustion of plane hydrogen microjet is found depending on its ignition far from or close to the nozzle exit and velocity variation.

The results of studies of the interaction process of two colliding axisymmetric microjets of propane/butane mixture with and without diffusion combustion are presented. The outflow of the gas mixture was carried out through round tubes at the same velocities. During the experiment, the transverse position of the tubes was varied while maintaining the angle between them. The features of the formation of the resulting jet depending on the transverse position of the tubes are defined. When the tubes are in the same plane, the resulting jet is formed in a plane orthogonal to it. This process is observed during the interaction of burning and non-burning jets. At increasing velocity of the jets, a region of local gap of the flame front was found.

Background: This article is devoted to the study of the effect of electrochemically activated water (catholyte with pH 9.3) on organic compounds of the plant matrix of brewer's spent grain in order to extract various compounds from it., Methods: Brewer's spent grain was obtained from barley malt at a pilot plant by mashing the malt followed by filtration and washing of the grain in water and storing it at (0 ± 2) °C in craft bags. For the organic compound quantitative determination, instrumental methods of analysis (HPLC) were used, and the results were subjected to mathematical analysis., Results: The study results showed that at atmospheric pressure, the alkaline properties of the catholyte showed better results compared to aqueous extraction with respect to β-glucan, sugars, nitrogenous and phenolic compounds, and 120 min was the best period for extraction at 50 °C. The excess pressure conditions used (0.5 ÷ 1 atm) revealed an increase in the accumulation of non-starch polysaccharide and nitrogenous compounds, while the level of sugars, furan and phenolic compounds decreased with increasing treatment duration. The waste grain extract ultrasonic treatment used revealed the effectiveness of catholyte in relation to the extraction of β-glucan and nitrogenous fractions; however, sugars and phenolic compounds did not significantly accumulate. The correlation method made it possible to reveal the regularities in the formation of furan compounds under the conditions of extraction with the catholyte: Syringic acid had the greatest effect on the formation of 5-OH-methylfurfural at atmospheric pressure and 50 °C and vanillic acid under conditions of excess pressure. Regarding furfural and 5-methylfurfural, amino acids had a direct effect at excess pressure. It was shown that the content of all furan compounds depends on amino acids with thiol groups and gallic acid; the formation of 5-hydroxymethylfurfural and 5-methylfurfural is influenced by gallic and vanillic acids; the release of furfural and 5-methylfurfural is determined by amino acids and gallic acid; excess pressure conditions promote the formation of furan compounds under the action of gallic and lilac acids., Conclusions: This study showed that a catholyte allows for efficient extraction of carbohydrate, nitrogenous and monophenolic compounds under pressure conditions, while flavonoids require a reduction in extraction time under pressure conditions.

Background: The present article considers the influence of malt with various adjuncts on beer organic compounds and taste profile composition, with more attention paid to the phenol complex change. The topic under consideration is relevant since it studies the interactions of phenolic compounds with other biomolecules, and expands the understanding of the adjuncts organic compounds contribution and their joint effect on beer quality., Methods: Samples of beer were analyzed at a pilot brewery using barley and wheat malts, barley, rice, corn and wheat, and then fermented. The beer samples were assessed by industry-accepted methods and using instrumental analysis methods (high-performance liquid chromatography methods-HPLC). The obtained statistical data were processed by the Statistics program (Microsoft Corporation, Redmond, WA, USA, 2006)., Results: The study showed that at the stage of hopped wort organic compounds structure formation, there is a clear correlation between the content of organic compounds and dry substances, including phenolic compounds (quercetin, catechins), as well as isomerized hop bitter resines. It is shown that the riboflavin content increases in all adjunct wort samples, and mostly with the use of rice-up to 4.33 mg/L, which is 9.4 times higher than the vitamin levels in malt wort. The melanoidin content in the samples was in the range of 125-225 mg/L and its levels in the wort with additives exceeded the malt wort. Changes in β-glucan and nitrogen with thiol groups during fermentation occurred with different dynamics and depending on the adjunct's proteome. The greatest decrease in non-starch polysaccharide content was observed in wheat beer and nitrogen with thiol groups content-in all other beer samples. The change in iso-α-humulone in all samples at the beginning of fermentation correlated with a decrease in original extract, and in the finished beer there was no correlation. The behavior of catechins, quercetin, and iso-α-humulone has been shown to correlate with nitrogen with thiol groups during fermentation. A strong correlation was shown between the change in iso-α-humulone and catechins, as well as riboflavin and quercetin. It was established that various phenolic compounds were involved in the formation of taste, structure, and antioxidant properties of beer in accordance with the structure of various grains, depending on the structure of its proteome., Conclusions: The obtained experimental and mathematical dependences make it possible to expand the understanding of intermolecular interactions of beer organic compounds and take a step toward predicting the quality of beer at the stage of using adjuncts.

Strontium titanate SrTiO 3 (STO) is a canonical example of a quantum paraelectric, and its doping with manganese ions unlocks its potential as a quantum multiferroic candidate. However, to date, the specifics of incorporation of the manganese ion into the perovskite lattice and its impact on structure-property relationships are debatable questions. Herein, using high-precision X-ray diffraction of a Mn (2 atom %)-doped STO single crystal, clear fingerprints of the displacement disorder of Mn cations in the perovskite B-sublattice are observed. Moreover, near the temperature of the antiferrodistortive transition, the off-center Mn position splits in two, providing the unequal potential barrier's distribution for possible local atomic hopping. A link with this was found via analysis of the dielectric response that reveals two Arrhenius-type relaxation processes with similar activation energies (35 and 43 meV) and attempt frequencies (1 × 10 11 and ∼1.6 × 10 10 Hz), suggesting similar dielectric relaxation mechanisms.

BiScO 3 compound was obtained in the form of dense ceramic with a perovskite-type structure, and its complex characterization was determined for the first time. The corresponding synthesis procedure is described in detail. It is demonstrated that the temperature region of the phase stability at atmospheric pressure lies at T < 700 °C (973 K). It is shown that the crystal structure of the BiScO 3 ceramic is centrosymmetric. Dielectric measurements of the synthesized sample performed at frequencies 25 Hz to 1 MHz and at temperatures 10-340 K show no changes typical for phase transition. Room-temperature infrared (30-15600 cm -1 ) and Raman (90-2000 cm -1 ) spectra of the prepared BiScO 3 ceramic are measured, and information on the parameters of phonon resonances is obtained. The number of infrared modes exceeds that predicted by the factor group analysis of the noncentrosymmetric space group C2. The reason for selection rules violation can be associated with the disorder of the crystal structure and local distortions induced by the lone pair of electrons of Bi 3+ .

Background: The article considers the phenolic hop compounds' effect on the quality indicators of finished beer. The topic under consideration is relevant since it touches on the beer matrix colloidal stability when compounds with potential destabilizing activity are introduced into it from the outside., Methods: The industrial beer samples' quality was assessed by industry-accepted methods and using instrumental analysis methods (high-performance liquid chromatography methods-HPLC). The obtained statistical data were processed by the Statistics program (Microsoft Corporation, Redmond, WA, USA, 2006)., Results: The study made it possible to make assumptions about the functional dependence of the iso-α-bitter resins and isoxanthohumol content in beer samples. Mathematical analysis indicate interactions between protein molecules and different malted grain and hop compounds are involved in beer structure, in contrast to dry hopped beer, where iso-a-bitter resins, protein, and coloring compounds were significant, with a lower coefficient of determination. The main role of rutin in the descriptor hop bitterness has been established in kettle beer hopping technology, and catechin in dry beer hopping technology, respectively. The important role of soluble nitrogen and β-glucan dextrins in the perception of sensory descriptors of various technologies' beers, as well as phenolic compounds in relation to the formation of bitterness and astringency of beer of classical technology and cold hopping, has been shown., Conclusions: The obtained mathematical relationships allow predicting the resulting beer quality and also make it possible to create the desired flavor profiles.

Aim: the aim of our study was to identify of structural transformations in the thymus and lymph nodes at the early stages of the development of an experimental prostate cancer., Materials and Methods: Experiments were performed on 60 adult male CBA mice weighing 28-30 g. An experimental model of a prostate cancer was created by inoculating a diluted cell strain of Ehrlich Ascites Carcinoma cells into the prostatic parenchyma through midline laparotomy under ether anesthesia. The animals were divided into three groups of 20 each: 1) control (intact animals) 2) animals on the 5th day of experimental prostate tumor growth and 3) animals on the 18th day of experimental prostate tumor growth. The pathological examination of the prostate, thymus, and pelvic lymph nodes was performed. The selection of structural components and cellular elements in the thymus and lymph nodes was carried out according to the International histological nomenclature., Results: According to the results, there was an increase in the percentage of connective tissue elements and glandular tissue increased in the thymus and the number of immunoblasts increased on the 5th day of the experiment. However, disorganization of the thymus structure was detected on the 18th day as well as an increase in the cortical substance, the number of epithelial reticular cells and decrease in the number of immunoblasts. On the 5th day, paracortical hyperplasia, sinus histiocytosis and activation of the blast transformation were detected in lymphatic nodes. On the 18th day, metastases, follicular reaction and activation of the transport function were determined., Conclusion: Our data suggest that the accidental thymus involution and impairment of transport and immune functions of pelvic lymph nodes in experimental prostate cancer. The severity of disturbances depends on the stage of prostate carcinogenesis.

Presented herein are the findings of studying the peculiarities of the systemic and regional haemodynamics in patients with obliterating atherosclerosis of the arteries of the lower limbs. We examined a total of 186 patients with stage I-IV chronic arterial ischaemia of the lower extremities using the following methods: computer-assisted TV microscopy of the vessels of the conjunctiva of the eyeball and of the skin of the lower limbs, laser Doppler flowmetry (LDF) and transcutaneous determination of oxygen tension. Revealed were: spastic, congestive, Presented herein are the findings of studying the peculiarities of the systemic and regional haemodynamics in patients with obliterating atherosclerosis of the arteries of the lower limbs. We examined a total of 186 patients with stage I-IV chronic arterial ischaemia of the lower extremities using the following methods: computer-assisted TV microscopy of the vessels of the conjunctiva of the eyeball and of the skin of the lower limbs, laser Doppler flowmetry (LDF) and transcutaneous determination of oxygen tension. Revealed were: spastic, congestive, spastic-atonic and stasic forms of microcirculatory disorders. It was determined that microcirculatory disorders in obliterating atherosclerosis of the lower limbs are systemic, to be revealed both in the extremities affected and in the conjunctiva of the eyeball. A pathophysiologically substantiated classification of microcirculatory disorders is proposed herein.

Experiments were conducted with CO2 and AIG laser on neodymium to study the condition of microcirculation and the degree of its disturbance in the wall of the small intestine in formation of a laser "welded" entero-enteral and termino-terminal anastomosis. The microcirculatory disorders and their extent were found to be directly dependent on the degree of the thermal effect and the width of the coagulation zone in the region of the suture. The results of the experiment confirmed that the suggested powers of the laser effect on the intestinal wall were optimal.

In 30 mammalian species specific peculiarities of the arterial structure has been revealed and their dependence on the type of the brain blood supply has been demonstrated. The architectonics of the blood supply sources is correlated with the structure of the wall in the arteries, immediately participating in dumping the blood stream during its transport to the brain.

Microcirculation in the patient's foot skin with different stages of arterial ischemia, was examined with the aid of TV-capillaroscopy, laser dopplerography, polarography of transcutaneous oxygen tension. The effect of semiconductor laser (wave length 0.98 mcm) on microcirculation system was studied. The dependence of capillary blood flow on the transcutaneous oxygen tension was determined. The laser therapy proved to be successful in the patients with the II and III stages of arterial ischemia.

The alterations taking place in the microvessels of the rat mesentery and liver under a photodynamic effect, were studied. Excitation of a photosensitizer injected preliminarily in the organism led to aggregation of thrombocytes in the lumen of hepatic and mesenteric microvessels until a complete obturation of the lumen. The dependence of the thrombocyte aggregate size on the duration of the photodynamic effect had a linear character whereas the photodynamic effect depended on the dosage of the photosensitizer. The level of fluorescence from the surface of the liver was found to decrease from the beginning of the photodynamic effect and become stable in hemostasis.

It was shown in experiments on white rats, that intravenous and direct myocardium helium-neon laser irradiation leads to the some activation of lactate, glucose-6-phosphate, succinate and reduced NAD degydrogenases. During direct myocardium irradiation these changes are in a less degree. It is suggested that helium-neon laser irradiation displays some active influence on the energy metabolism enzymes of the myocardium, and the mechanisms of this action are discussed.

Functional manifestations of biological ultradian rhythms in the adrenal cortex were first confirmed on the cytologic level. The cycle of the ultradian rhythm in the cells of the adrenal cortex fascicular zone consisted was determined to involve three phases: accumulation of lipids, delipoidization, and the rest period. A definite volume of cells and their nuclei, certain nuclear-cytoplasmic relations, the number of liposomes and mitochondria on the square unit are characteristic of each phase. The activity of cells is especially high during the second phase which is characterized by the increase in nuclear sizes and nuclear-cytoplasmatic relations, by the decrease in cell volume and in the number of liposomes in their cytoplasm; this is indicative of the rised synthesis and secretion of hormones. It is underlined that the cell volume increases when liposomes are accumulated in the cytoplasm to decrease upon their disappearance.

Three phases have been detected in the fascicular zone of the white rat adrenal cortex. During the first phase (normoemia) blood stream is rather moderate, lipids accumulate in adrenocorticocytes. This results in increase of their volume and in decrease of nuclear-cytoplasmic relations. The second phase (functional hyperemia) is characterized with an elevated blood stream and plethora, maximal parameters of nuclear volume and nuclear-cytoplasmic relations, decreasing content of lipids and volume of adrenocorticocytes. During the third phase (functional hypoemia) parameters characterising intensity of blood stream, nuclear volume and nuclear-cytoplasmic relations decrease.

Hypokinesia (Hk) lasting for 150 days has been modelling on Wistar male rats by means of their holding in special boxes. After decapitation in 10, 20, 50, 100 and 150 days the muscles of their extremities have been studied, using stereological methods. At Hk, especially for 50 days, inhibition of morphogenesis of ultrastructures and development of certain pathological processes are noted in the muscles with their preponderance in red fibers. Laser puncture stimulates formation of the ultrastructures responsible for contraction and energy supply and sharply decreases development of the destructive processes in muscle fiber, thus providing a satisfactory endurance of hypokinesia.

Increase of capillaries blood volume, nuclear mass and nuclear cytoplasmic relationship and decrease of lipid content and adrenocortical sizes were determined in superficial adrenocortical layers on helium-neon LAZER irradiation of uncovered left adrenal glands in white female rats. It was confirmed by corticosteroid function increase. Similar morphometric changes were identified all over adrenocortical bundles on arsenate-helium irradiation of covered left adrenal gland from the back of the animal. According to obtained results LAZER irradiation may be recommended to use for functional stimulation of adrenal cortex.

The reconstruction of the mesenterium microcirculatory bed was performed intravitally in albino rats and cats after biomicrophotograms. The number, length and caliber of arterioles, pericapillary arteriolec, capillaries, postcapillary venules and venules of the mesenterium were measured. According to these data summary indices of the cross section, surface and volume of the vessels of various functional subdivisions of the microcirculatory bed were calculated. The blood volume entering the microcirculatory system of the albino rat's mesenterium is distributed in the vessels as follows: 8,4% -- arterioles, 10,2% -- pericapillary arterioles, 41,9% -- capillaries, 22,1% -- postcapillary venules and 17,4% -- venules. Similar correlations were found in the cat. The working surface of capillaries is 60--70% of the working surface of all the vessels of the mesenterial microcirculatory system. The evidence of the functional variability of the microcirculatory bed geometry depending on the tissue needs in blood supply is presented.

Biomicroscopic studies performed in anesthetized white rats revealed the increase in the cortex mass and the formation of microcirculatory bed as the main factors in microcirculation development. Three periods were distinguished in the process of the pial microcirculatory system formation: an excessive blood flow in the primary capillary net (1-7 days); an unstable (translocating) blood flow and formation of definite structure of the microcirculatory bed (7-30 days); a stable blood flow and stabilizing of the microcirculatory bed construction (75-90 days). A possibility of distinguishing the structural-functional units within the pial microcirculatory system and their role in formation of the microcirculation in ontogenesis, are discussed.

In 261 girls year-to-year morphofunctional transformations of spatial composition of the skin microcirculatory bed have been studied at rest and after a dynamic local load. By means of biomicroscopy main regularities in development of the skin capillary network have been revealed in the nail torus in the postnatal ontogenesis. Formation of the microvessels reactivity during various age periods and maturation of mechanisms of the compensatory-adaptive reactions are connected with formation of the definitive composition of the microcirculatory bed, that in girls corresponds to 11-12 years. Qualitative transformations in the skin capillary network bring certain quantitative changes in the structural microcirculatory parameters--increasing diameter of microvessels and increasing density of functioning capillaries.

The sensitivity of rat's microvessels of microcirculatory bed of brain's pia matter was studied by helium-neon laser radiation. Changes in the reactivity by the microscopy findings were studied on the 7, 30, 45, 60, 90th days of animals postnatal development. Laser radiation was used during 30 min. Local changes in all components of the microcirculatory bed were fixed. It is mentioned that in adult rat the expressiveness of arteriole's local widening reaction in the radiated place reduces, but the degree of the reduction is below or over the radiated place, on the contrary, increases. The arteriole diameter in 30-day old rats increases to 59% in comparison to the initial level, and 90th day old animals--to 16%. The degree of reaction's expressiveness depends upon the microvessel diameter and the animal's age.

Permeability of m. quadriceps femoris and m. gastrocnemius mimicrocirculatory bed of albino rats was studied by fluorescent biomicroscopy at rest and under work hyperemia. Fluorescein-labeled bovine globulin (FBG) was used as an indicator of permeability alteration. Quantitative fluorescent analysis was carried out on a microspectrofluorimeter. In work hypermia the FBG concentration in the muscle exceeded such at rest by 40--45%; this evidenced an increased transendothelial transport. The results of the experiments on the measurement of FBG concentration about a single capillary suggested that the microcirculatory bed permeability increased under work hyperemia.

Microcirculation of the gastric wall in the albino rat was studied by the method of vital microscopy in passing light. The conditions of the experiment permitted watching the microcirculation state during 5-6 hours. Intravital morphometry of the microcirculation bed vessels was made. The obtained data concerning the intravital angioarchitectonics of the gastric wall vascular bed were in good agreement with a conventional scheme of its blood supply. The role of arteriolevenular anastomoses in redistribution of blood within the bloodflow pathways was noted.

The survey of the works, performed during the 11th five-year period in studying general biological regularities of microcirculation, demonstrates certain success in investigations developed in the following directions: functional geometry of the hemo-microcirculatory bed; elaboration of quantitative and qualitative analysis methods of the microcirculatory system elements; functional morphology of the vascular endothelium; experimental analysis of adaptive mechanisms of the microcirculatory bed; clinical-morphological investigations of microcirculation. Formation of structural-functional units, ensuring specialization of microcirculation in organs, forms the base of the functional geometry of the microcirculatory bed. This makes necessary conditions for compartmentalization of some micro-region in an organ and spatial distribution of various liquid media in dependence of certain topology of microvessels. The most perspective ways in development of morphological investigations, concerning the general biological regularities of microcirculation, are discussed.

It has been shown that the microcirculatory system of the cohlear portion of the labyrinth is a complex of vessels adapted to the organ function. The analysis of the blood passages in the cochlear channel has shown that in accordance with the organ structure there occurs a spacious subdivision of the micrcirculatory bed into working units (segments) which are functionally integrated into a single microcirculatory system. Quantitative estimation of the microcirculatory system parameters has shown that 1) the blood volume which comes into the microcirculatory system is distributed between the vessels as following: 26%--arterioles: 8%--precapillaries; 29%--capillaries; 8%--postcapillaries and 29%--venules. 2) 639 capillaries fall on 1 mm-2 of the vascular strip and their diffuse surface is 1,3 mm-2.

Structural changes and hemodynamic relations have been studied in the microcirculatory bed of the white rat small intestine mesentery during sex maturation (from the 3d up to the 10th week of the postnatal development). All calculations are performed regarding the mesenteric segment limited with two intestinal arteries, which is considered as an elementary microvascular module. Complication of the microcirculatory bed construction takes place at the expense of increasing number (nearly five-fold) of microvessels in the segment and increase of the capillary network density. The hemodynamic factor plays a certain role for stimulating the process of the capillary growth. The definitive structure of the mesenteric microcirculatory bed is completed by the 7th week. The main rearrangement of the microcirculatory system during the developmental process from a simple arterio-venular loop up to a complex microcirculatory bed with a branching capillary network is performed within the limits of the mesenteric segment.