Data on the solubility of oligomer polystyrene (PS) and poly(methyl methacrylate) (PMMA) of various molecular weights have been obtained. The binodal and spinodal curves of the phase state diagram ...with the upper critical solution temperature (UCST) are constructed through simulation within the framework of the Flory-Huggins theory. The influence of the molecular weight of polymers on the contribution to their mixing has been compared, and correlation curves have been plotted. The interaction parameters were calculated and the mixing thermodynamics of the components was evaluated. The largest contribution was made by the entropy component. Also, it has been shown using IR spectroscopy that there is no interaction between the functional groups of polystyrene and poly(methyl methacrylate) in a homogeneous mixture.
Nine species-level taxa of bat ectoparasites, three chigger mites (Trombiculidae), three hard (Ixodidae), and one soft tick (Argasidae) species, as well as two bug (Cimicidae) species from nine bat ...species hosts were detected in the Eastern Palaearctic. Trombiculid larvae of
Leptotrombidium schlugerae
,
Leptotrombidium album,
and
Ascoschoengastia latyshevi
were first recorded on bats in the temperate zone of eastern Russia.
L. schlugerae
was more abundant than
A. latyshevi
in the same study sites in Eastern Siberia, and the main hosts of both chigger species were
Plecotus ognevi
and
Eptesicus nilssonii
. Ixodid ticks
Dermacentor marginatus
,
Ixodes simplex,
and
Ixodes
sp. were sampled from bats in Kazakhstan, the Far East, and Eastern Siberia, respectively. Phylogenetic analysis based on
Cox
1, 16S rDNA, and ITS2 sequences of
I. simplex
showed that the specimens from the Far East grouped into a clade distributed in the Eastern Palaearctic and India. In turn, the specimen of
Ixodes
sp. from Eastern Siberia was most closely related to
Ixodes soricis
and
Ixodes angustus
with
p
-distance of 9.8–10.7% (
Cox
1), suggesting that this tick probably belongs to a new species.
Argas vespertilionis
larvae were collected from three widespread bat species in Kazakhstan. Two bug species,
Cimex pipistrelli
and
Cimex
aff.
lectularius
, were recorded in the Far East and Eastern Siberia, respectively. Specimens from Transbaikalia were morphologically identified as
Cimex lectularius
. However, they differed from the latter by 12.5–12.9% of
Cox
1 sequences, indicating that
C.
aff.
lectularius
may be a new species.
The phase state diagram of the poly(vinyl methyl ether)-water system in a wide concentration range was obtained by the optical interferometry method. It was shown that this system was characterized ...by a complicated phase equilibrium with two lower critical solution temperatures, one of which was located in the concentrated region at 21 °C, and the other one in the region of a dilute solution at 31 °C. In the framework of the Flory-Huggins theory, pair interaction parameters were calculated for different parts of the binodal curves, and an attempt was made to reverse simulate the diagram in different conditions. It was suggested that the unusual character of the diagram was associated with the formation of a complicated complex between PVME and water in the middle region of the compositions. Concentration profiles for different temperatures were constructed. For the first time for this system, the numerical values of the diffusion coefficients of poly(vinyl methyl ether) (PVME) into water and water in PVME were obtained. Concentration and temperature dependences of diffusion coefficients were constructed and analyzed. The kinetics of water sorption in PVME was plotted, the clustering integral was calculated, and the approximate number of molecules in a water cluster was estimated. It was shown that in the dilute solution region upon passing through the binodal curve, the interphase disappeared immediately, and the remaining fluctuation of the concentration decreased in size with time. The kinetics of this process was estimated from the change in the size of such a particle.
The phase diagrams of polystyrene (PS)‐poly(vinyl methyl ether) (PVME) system obtained via optical interferometry in the study of polymer interdiffusion are presented. The influence of molecular ...weight of the PS on the position of the binodal curve dome and the critical point is shown. Paired interaction parameters and their temperature dependences are calculated in the framework of Flory‐Huggins theory both for the present experimental diagrams and for the ones, previously obtained by different authors. It is shown that the generalized temperature dependence of the Flory‐Huggins parameter can be used to model phase equilibrium in a wide range of temperatures and compositions. For the first time for PS‐PVME system, the generalized phase state diagram characterized by both lower and upper critical solution temperatures is calculated and constructed.
The solubility and interdiffusion of polystyrene (PS) with polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate (PBA), and polyethylhexyl acrylate (PEHA) have been studied by the ...optical interferometry method. Phase state diagrams are plotted. It is shown that they are characterized by the upper critical solution temperatures (UCST), which are localized in the temperature range above 450 K. Pair interaction parameters and their temperature dependences are determined and analyzed. Extrapolation of the temperature dependence of the interaction parameter was used to construct the dome of binodal curves and determine the spinodal curves in the framework of the Flory–Huggins theory. The diffusion coefficients of polystyrene into polyacrylates and polyacrylates into polystyrene are calculated. The dependences of the interdiffusion coefficients on the concentration, temperature, polystyrene molecular weight, and the number of carbons in the side chain of polyacrylate are analyzed. The numerical values of the interdiffusion coefficients of PS-1 into polyacrylates at 433 K change as −8.5 → −6.7 → −6.4 in the homologous series PMA → PEA → PBA. The coefficients of friction are calculated and the effect of change in the matrix structure on the diffusion of polystyrene in them is estimated.
Phase equilibria, interdiffusion and structure in the initial uncured mixtures of epoxy oligomer-polysulfone-alkyl glycidyl ether were studied. Binodal curves were constructed on isothermal sections ...of the ternary phase diagram. Thermodynamic mixing parameters were calculated and spinodal curves were plotted. The interdiffusion coefficients of components, establishing the technological modes of mixing the components, were determined. To validate the phase diagram, the phase structure of mixtures, the composition of which at a temperature of 40 °C corresponds to heterogeneous and homogeneous regions, was studied.
Fruit flies have eight identified
insulin-like peptides (DILPs) that are involved in the regulation of carbohydrate concentrations in hemolymph as well as in accumulation of storage metabolites. In ...the present study, we investigated diet-dependent roles of DILPs encoded by the genes
-
, and
in the regulation of insect appetite, food choice, accumulation of triglycerides, glycogen, glucose, and trehalose in fruit fly bodies and carbohydrates in hemolymph. We have found that the wild type and the mutant lines demonstrate compensatory feeding for carbohydrates. However, mutants on
, and
showed higher consumption of proteins on high yeast diets. To evaluate metabolic differences between studied lines on different diets we applied response surface methodology. High nutrient diets led to a moderate increase in concentration of glucose in hemolymph of the wild type flies. Mutations on
genes changed this pattern. We have revealed that the
mutation led to a drop in glycogen levels independently on diet, lack of
led to dramatic increase in circulating trehalose and glycogen levels, especially at low protein consumption. Lack of
led to decreased levels of glycogen and triglycerides on all diets, whereas knockout on
caused increase in glycogen levels and simultaneous decrease in triglyceride levels at low protein consumption. Fruit fly appetite was influenced by
and
genes. Our data contribute to the understanding of
as a model for further studies of metabolic diseases and may serve as a guide for uncovering the evolution of metabolic regulatory pathways.
A new approach is proposed for simulating binodal and spinodal curves of phase diagrams for binary polymer systems. It is shown that the Flory–Huggins theory makes it possible to predict phase ...behavior in a wide range of temperatures and concentrations based on limited data on the components’ solubility. The approbation data of the technique are presented in the example of PS–PB and PS–PMMA systems, for which generalized phase diagrams are constructed.
More than five hundred images of individual macromolecules of random styrene-butadiene copolymers and styrene-isoprene block copolymers dissolved in a polystyrene matrix were analyzed. The presence ...of density fluctuations inside the macromolecular coil has been established. Within the framework of the model of harmonic oscillations, the radial distribution of such density fluctuations is estimated.
Continuous casting control via drive monitoring Barankova Inna, I.; Mikhailova Uliana, V.; Antropova Lyudmila, I. ...
International journal of advanced manufacturing technology,
04/2020, Letnik:
107, Številka:
11-12
Journal Article
Recenzirano
The paper describes the investigation’s results of functional capabilities of the equipment testing systems as applied to the withdrawal roll drives provided with individual power supply using the ...frequency converter-asynchronous motor system. All the experimental investigations were carried out at the “Magnitogorsk Iron and Steel Works” (MISW). The statistical analysis of time diagrams and frequency-response curve of changes in instantaneous values of withdrawal roll drives load torques were used. The diagnostic signs of the withdrawal roll bending, occasional slippage along the slab, wear of ring seals, and teeth of the mounted gearbox on the basis of the analysis of the component range of spectrum density of changes in load torques were computed. It was found that variance inhomogeneity of scattering of load torque change for adjacent time intervals can be used as a diagnostic sign of the withdrawal roll occasional slippage along the slab. We considered the developed diagnostic methods for withdrawal roll drive equipment at continuous casting machines (CCMs) which provide the increase productivity due to decreasing of the CCM repair work downtime. A functional diagram and a generalized algorithm of the diagnostic system for equipment of the withdrawal roll were developed taking into account the characteristics of continuous casting of steel at a slab CCM. An experimental estimate was carried out to assess the efficiency of the developed diagnostic system.
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