Yuri Tarasevich | Astrakhan State University (original) (raw)
Papers by Yuri Tarasevich
The electrical conductivity of a monolayer produced by the random sequential adsorption (RSA) of ... more The electrical conductivity of a monolayer produced by the random sequential adsorption (RSA) of linear k-mers (particles occupying k adjacent adsorption sites) onto a square lattice was studied by means of computer simulation. Overlapping with pre-deposited k-mers and detachment from the surface were forbidden. The RSA process continued until the saturation jamming limit, pj. The isotropic (equiprobable orientations of k-mers along x and y axes) and anisotropic (all k-mers aligned along the y axis) depositions for two different models: of an insulating substrate and conducting k-mers (C-model) and of a conducting substrate and insulating k-mers (I-model) were examined. The Frank-Lobb algorithm was applied to calculate the electrical conductivity in both the x and y directions for different lengths (k = 1 – 128) and concentrations (p = 0 – pj) of the k-mers. The 'intrinsic electrical conductivity' and concentration dependence of the relative electrical conductivity Σ(p) (Σ = σ/σm for the C-model and Σ = σm/σ for the I-model, where σm is the electrical conductivity of substrate) in different directions were analyzed. At large values of k the Σ(p) curves became very similar and they almost coincided at k = 128. Moreover, for both models the greater the length of the k-mers the smoother the functions Σxy(p), Σx(p) and Σy(p). For the more practically important C-model, the other interesting findings are (i) for large values of k (k = 64, 128), the values of Σxy and Σy increase rapidly with the initial increase of p from 0 to 0.1; (ii) for k ≥ 16, all the Σxy(p) and Σx(p) curves intersect with each other at the same iso-conductivity points; (iii) for anisotropic deposition, the percolation concentrations are the same in the x and y directions, whereas, at the percolation point the greater the length of the k-mers the larger the anisotropy of the electrical conductivity, i.e., the ratio σy/σx (> 1).
The vertical drying of a colloidal film containing rod-like particles was studied by means of kin... more The vertical drying of a colloidal film containing rod-like particles was studied by means of kinetic Monte Carlo (MC) simulation. The problem was approached using a two-dimensional square lattice and the rods were represented as linear k-mers (i.e., particles occupying k adjacent sites). The initial state before drying was produced using a model of random sequential adsorption (RSA) with isotropic orientations of the k-mers (orientation of the k-mers along horizontal x and vertical y directions are equiprobable). In the RSA model, overlapping of the k-mers is forbidden. During the evaporation, an upper interface falls with a linear velocity of u in the vertical direction and the k-mers undergo translation Brownian motion. The MC simulations were run at different initial concentrations, pi, (pi ∈ [0, pj], where pj is the jamming concentration), lengths of k-mers (k ∈ [1, 12]), and solvent evaporation rates, u. For completely dried films, the spatial distributions of k-mers and their electrical conductivities in both x and y directions were examined. Significant evaporation-driven self-assembly and orientation stratification of the k-mers oriented along the x and y directions were observed. The extent of stratification increased with increasing value of k. The anisotropy of the electrical conductivity of the film can be finely regulated by changes in the values of pi, k and u.
Physical Review E, 2015
Using the Monte Carlo simulation, we study the percolation and jamming of oriented linear k-mers ... more Using the Monte Carlo simulation, we study the percolation and jamming of oriented linear k-mers on a square lattice that contains defects. The point defects with a concentration d are placed randomly and uniformly on the substrate before deposition of the k-mers. The general case of unequal probabilities for orientation of depositing of k-mers along different directions of the lattice is analyzed. Two different relaxation models of deposition that preserve the predetermined order parameter s are used. In the relaxation random sequential adsorption (RRSA) model, the deposition of k-mers is distributed over different sites on the substrate. In the single-cluster relaxation (RSC) model, the single cluster grows by the random accumulation of k-mers on the boundary of the cluster (Eden-like model). For both models, a suppression of growth of the infinite (percolation) cluster at some critical concentration of defects d(c) is observed. In the zero-defect lattices, the jamming concentration p(j) (RRSA model) and the density of single clusters p(s) (RSC model) decrease with increasing length k-mers and with a decrease in the order parameter. For the RRSA model, the value of d(c) decreases for short k-mers (k<16) as the value of s increases. For k=16 and 32, the value of d(c) is almost independent of s. Moreover, for short k-mers, the percolation threshold is almost insensitive to the defect concentration for all values of s. For the RSC model, the growth of clusters with ellipselike shapes is observed for nonzero values of s. The density of the clusters p(s) at the critical concentration of defects d(c) depends in a complex manner on the values of s and k. An interesting finding for disordered systems (s=0) is that the value of p(s) tends towards zero in the limits of the very long k-mers, k→∞, and very small critical concentrations d(c)→0. In this case, the introduction of defects results in a suppression of k-mer stacking and in the formation of empty or loose clusters with very low density. On the other hand, denser clusters are formed for ordered systems with p(s)≈0.065 at s=0.5 and p(s)≈0.38 at s=1.0.
Physical Review E, 2015
The jamming and percolation for two generalized models of random sequential adsorption (RSA) of l... more The jamming and percolation for two generalized models of random sequential adsorption (RSA) of linear k-mers (particles occupying k adjacent sites) on a square lattice are studied by means of Monte Carlo simulation. The classical random sequential adsorption (RSA) model assumes the absence of overlapping of the new incoming particle with the previously deposited ones. The first model LK d is a generalized variant of the RSA model for both k-mers and a lattice with defects. Some of the occupying k adjacent sites are considered as insulating and some of the lattice sites are occupied by defects (impurities). For this model even a small concentration of defects can inhibit percolation for relatively long k-mers. The second model is the cooperative sequential adsorption (CSA) one, where, for each new k-mer, only a restricted number of lateral contacts z with previously deposited k-mers is allowed. Deposition occurs in the case when z ≤ (1 − d)zm where zm = 2(k + 1) is the maximum numbers of the contacts of k-mer, and d is the fraction of forbidden NN contacts. Percolation is observed only at some interval kmin ≤ k ≤ kmax where the values kmin and kmax depend upon the fraction of forbidden contacts d. The value kmax decreases as d increases. A logarithmic dependence of the type log(kmax) = a + bd, where a = −4.03 ± 0.22, b = 4.93 ± 0.57, is obtained.
The European Physical Journal E, 2016
In our model, we simulate an experiment (D.J. Harris, H. Hu, J.C. Conrad, J.A. Lewis, Patterning ... more In our model, we simulate an experiment (D.J. Harris, H. Hu, J.C. Conrad, J.A. Lewis, Patterning colloidal films via evaporative lithography, Phys. Rev. Lett. 98, 148301 (2007)). A thin colloidal sessile droplet is allowed to dry out on a horizontal hydrophilic surface. A mask just above the droplet predominantly allows evaporation from the droplet free surface directly beneath the holes in the mask. We consider one special case, when the holes in the mask are arranged so that the system has rotational symmetry of order m . We use a speculative evaporative flux to mimic the real system. Advection, diffusion, and sedimentation are taken into account. FlexPDE is utilized to solve an advection-diffusion equation using the finite element method. The simulation demonstrates that the colloidal particles accumulate below the holes as the solvent evaporates. Diffusion can reduce this accumulation.
Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been p... more Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been performed to study the percolation behavior of linear kkk-mers (also denoted in the literature as rigid rods, needles, sticks) on two-dimensional square lattices LtimesLL \times LLtimesL with periodic boundary conditions. Percolation phenomena are investigated for anisotropic relaxation random sequential adsorption of linear kkk-mers. Especially, effect of anisotropic placement of the objects on the percolation threshold has been investigated. Moreover, the behavior of percolation probability RL(p)R_L(p)RL(p) that a lattice of size LLL percolates at concentration ppp has been studied in details in dependence on kkk, anisotropy and lattice size LLL. A nonmonotonic size dependence for the percolation threshold has been confirmed in isotropic case. We propose a fitting formula for percolation threshold pc=a/kalpha+blog10k+cp_c = a/k^{\alpha}+b\log_{10} k+ cpc=a/kalpha+blog10k+c, where aaa, bbb, ccc, alpha\alphaalpha are the fitting parameters varying with anisotropy. We predict that for large kkk-mers ($k\gtrapprox 1.2\times10^4$) isotropic placed at the lattice, percolation cannot occur even at jamming concentration.
Physical review. E, Statistical, nonlinear, and soft matter physics, 2015
The effect of defects on the percolation of linear k-mers (particles occupying k adjacent sites) ... more The effect of defects on the percolation of linear k-mers (particles occupying k adjacent sites) on a square lattice is studied by means of Monte Carlo simulation. The k-mers are deposited using a random sequential adsorption mechanism. Two models L(d) and K(d) are analyzed. In the L(d) model it is assumed that the initial square lattice is nonideal and some fraction of sites d is occupied by nonconducting point defects (impurities). In the K(d) model the initial square lattice is perfect. However, it is assumed that some fraction of the sites in the k-mers d consists of defects, i.e., is nonconducting. The length of the k-mers k varies from 2 to 256. Periodic boundary conditions are applied to the square lattice. The dependences of the percolation threshold concentration of the conducting sites p(c) vs the concentration of defects d are analyzed for different values of k. Above some critical concentration of defects d(m), percolation is blocked in both models, even at the jamming c...
Procedia Computer Science, 2014
We present our experience to implement a Current Research Information System in the Astrakhan Sta... more We present our experience to implement a Current Research Information System in the Astrakhan State University, Russia. The CRIS covers research information such as publications, funding, projects, and patents. Education, training, professional activity, and expertise are also within the scope of the CRIS. The metadata of research output are stored as a single record, regardless of the number of contributors and their belonging to different divisions. Data linkage associates a research output with contributors and their departments. A faculty fills own profile and links the metadata with co-authors. The more active and responsible users employ the CRIS, the more complete and reliable is information. Some metadata are imported from external data sources, in particular from Russian Science Citation Index. CRIS can generate Statistical Reports, CV's, Publication Lists, ratings, etc. When implementing the system the main problems are not technical but organizational. The bureaucratic obstacles hinder the exchange of information between different sources. The managerial staff does not demonstrate the real interest in getting actual, complete and accurate information about the research outputs. Some of the faculty has rather little computer skills and low interest in filling the database.
Condensed Matter Physics, 2014
This work studies the jamming and percolation of parallel squares in single-cluster growth model.... more This work studies the jamming and percolation of parallel squares in single-cluster growth model. The Leath-Alexandrowicz method was used to grow a cluster from an active seed site. The sites of a square lattice were occupied by addition of the equal size k × k squares (E-problem) or a mixture of k × k and m × m (m ≤ k) squares (M-problem). The larger k ×k squares were assumed to be active (conductive) and the smaller m×m squares were assumed to be blocked (non-conductive). For equal size k × k squares (E-problem) the value of p j = 0.638 ± 0.001 was obtained for the jamming concentration in the limit of k → ∞. This value was noticeably larger than that previously reported for random sequential adsorption model, p j = 0.564 ± 0.002. It was observed that the value of percolation threshold pc (i.e., the ratio of the area of active k × k squares and the total area of k × k squares in the percolation point) increased with increase of k. For mixture of k × k and m × m squares (M-problem) the value of pc increased noticeably with increase of k at fixed value of m and approached 1 at k ≥ 10m. It reflects that percolation of larger active squares in M-problem can be effectively suppressed in the presence of smaller blocked squares.
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2014
ABSTRACT Formation of the ring-like pattern by nano-particles of the desiccated droplet of a lapo... more ABSTRACT Formation of the ring-like pattern by nano-particles of the desiccated droplet of a laponite-based aqueous nanofluid (the well known 'coffee-ring effect') is studied. The temperature was controlled and fixed (T = 300 K). The laponite concentration was controlled and varied in order to investigate its effect on the pattern formation. It was observed that the coffee-ring effect vanishes if concentration of laponite exceeds 5%. A simple model for analysis of colloidal sessile droplet desiccation is proposed. The model describes correctly dynamics of the drying droplet profile and the final shape of the dried film (deposit). The model is based on the mass conservation law and reasonable assumption that deposit (gel phase) prevents the flows.
Technical Physics, 2007
It is shown that, when a drop of a biological fluid dries out on a substrate, diffusion processes... more It is shown that, when a drop of a biological fluid dries out on a substrate, diffusion processes to a great extent suppress the transfer of the salt toward the periphery of the drop by capillary flows and still have a minor effect on the motion of colloid particles.
Technical Physics, 2001
In [1], for computer simulations of salt crystal growth from biological fluids, the so-called τ-m... more In [1], for computer simulations of salt crystal growth from biological fluids, the so-called τ-model was put forward. This model was used to describe the crystal growth under different conditions [1–5]. However, our independent investigation indicates that the conclusions obtained with the τ-model are not confirmed. The effects observed are related to mistakes in the algorithm.
Physics-Uspekhi, 2004
... 10. Variation of the magnetic properties of a protein solution during drying 726 ... The foll... more ... 10. Variation of the magnetic properties of a protein solution during drying 726 ... The following processes are observed in the dehydration of biological fluids. ... This motion is typical of dryingdroplets of solutions, including colloidal ones, and was studied at length in Refs [12 ± 14]. ...
Physics of the Solid State, 1997
ABSTRACT
Physical Review E, 2012
Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been p... more Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been performed to study the percolation behavior of linear k-mers (also denoted in the literature as rigid rods, needles, sticks) on two-dimensional square lattices L × L with periodic boundary conditions. Percolation phenomena are investigated for anisotropic relaxation random sequential adsorption of linear k-mers. Especially, effect of anisotropic placement of the objects on the percolation threshold has been investigated. Moreover, the behavior of percolation probability RL(p) that a lattice of size L percolates at concentration p has been studied in details in dependence on k, anisotropy and lattice size L. A nonmonotonic size dependence for the percolation threshold has been confirmed in isotropic case. We propose a fitting formula for percolation threshold pc = a/k α + b log 10 k + c, where a, b, c, α are the fitting parameters varying with anisotropy. We predict that for large kmers (k 1.2 × 10 4 ) isotropic placed at the lattice, percolation cannot occur even at jamming concentration.
physica status solidi (b), 1992
ABSTRACT
Ferroelectrics, 1992
ABSTRACT
Ferroelectrics, 1992
ABSTRACT
Ferroelectrics, 1995
ABSTRACT
Journal de Physique IV (Proceedings), 2005
Monte Carlo simulation studies were performed to examine the implications of octahedral cation an... more Monte Carlo simulation studies were performed to examine the implications of octahedral cation antisite disorder for magnetization in the double 1:1 perovskites A2+(B13+{1/2}B25+{1/2}) O{3}: Sr{2}FeMoO{6} (SFMO) and Pb{2}FeNbO{6} (PFN) at finite temperature. The percolation approach was applied at 0 K. We found that about 14.5 % of antisite defects is a critical value for the properties of the 1:1 double perovskites.
The electrical conductivity of a monolayer produced by the random sequential adsorption (RSA) of ... more The electrical conductivity of a monolayer produced by the random sequential adsorption (RSA) of linear k-mers (particles occupying k adjacent adsorption sites) onto a square lattice was studied by means of computer simulation. Overlapping with pre-deposited k-mers and detachment from the surface were forbidden. The RSA process continued until the saturation jamming limit, pj. The isotropic (equiprobable orientations of k-mers along x and y axes) and anisotropic (all k-mers aligned along the y axis) depositions for two different models: of an insulating substrate and conducting k-mers (C-model) and of a conducting substrate and insulating k-mers (I-model) were examined. The Frank-Lobb algorithm was applied to calculate the electrical conductivity in both the x and y directions for different lengths (k = 1 – 128) and concentrations (p = 0 – pj) of the k-mers. The 'intrinsic electrical conductivity' and concentration dependence of the relative electrical conductivity Σ(p) (Σ = σ/σm for the C-model and Σ = σm/σ for the I-model, where σm is the electrical conductivity of substrate) in different directions were analyzed. At large values of k the Σ(p) curves became very similar and they almost coincided at k = 128. Moreover, for both models the greater the length of the k-mers the smoother the functions Σxy(p), Σx(p) and Σy(p). For the more practically important C-model, the other interesting findings are (i) for large values of k (k = 64, 128), the values of Σxy and Σy increase rapidly with the initial increase of p from 0 to 0.1; (ii) for k ≥ 16, all the Σxy(p) and Σx(p) curves intersect with each other at the same iso-conductivity points; (iii) for anisotropic deposition, the percolation concentrations are the same in the x and y directions, whereas, at the percolation point the greater the length of the k-mers the larger the anisotropy of the electrical conductivity, i.e., the ratio σy/σx (> 1).
The vertical drying of a colloidal film containing rod-like particles was studied by means of kin... more The vertical drying of a colloidal film containing rod-like particles was studied by means of kinetic Monte Carlo (MC) simulation. The problem was approached using a two-dimensional square lattice and the rods were represented as linear k-mers (i.e., particles occupying k adjacent sites). The initial state before drying was produced using a model of random sequential adsorption (RSA) with isotropic orientations of the k-mers (orientation of the k-mers along horizontal x and vertical y directions are equiprobable). In the RSA model, overlapping of the k-mers is forbidden. During the evaporation, an upper interface falls with a linear velocity of u in the vertical direction and the k-mers undergo translation Brownian motion. The MC simulations were run at different initial concentrations, pi, (pi ∈ [0, pj], where pj is the jamming concentration), lengths of k-mers (k ∈ [1, 12]), and solvent evaporation rates, u. For completely dried films, the spatial distributions of k-mers and their electrical conductivities in both x and y directions were examined. Significant evaporation-driven self-assembly and orientation stratification of the k-mers oriented along the x and y directions were observed. The extent of stratification increased with increasing value of k. The anisotropy of the electrical conductivity of the film can be finely regulated by changes in the values of pi, k and u.
Physical Review E, 2015
Using the Monte Carlo simulation, we study the percolation and jamming of oriented linear k-mers ... more Using the Monte Carlo simulation, we study the percolation and jamming of oriented linear k-mers on a square lattice that contains defects. The point defects with a concentration d are placed randomly and uniformly on the substrate before deposition of the k-mers. The general case of unequal probabilities for orientation of depositing of k-mers along different directions of the lattice is analyzed. Two different relaxation models of deposition that preserve the predetermined order parameter s are used. In the relaxation random sequential adsorption (RRSA) model, the deposition of k-mers is distributed over different sites on the substrate. In the single-cluster relaxation (RSC) model, the single cluster grows by the random accumulation of k-mers on the boundary of the cluster (Eden-like model). For both models, a suppression of growth of the infinite (percolation) cluster at some critical concentration of defects d(c) is observed. In the zero-defect lattices, the jamming concentration p(j) (RRSA model) and the density of single clusters p(s) (RSC model) decrease with increasing length k-mers and with a decrease in the order parameter. For the RRSA model, the value of d(c) decreases for short k-mers (k<16) as the value of s increases. For k=16 and 32, the value of d(c) is almost independent of s. Moreover, for short k-mers, the percolation threshold is almost insensitive to the defect concentration for all values of s. For the RSC model, the growth of clusters with ellipselike shapes is observed for nonzero values of s. The density of the clusters p(s) at the critical concentration of defects d(c) depends in a complex manner on the values of s and k. An interesting finding for disordered systems (s=0) is that the value of p(s) tends towards zero in the limits of the very long k-mers, k→∞, and very small critical concentrations d(c)→0. In this case, the introduction of defects results in a suppression of k-mer stacking and in the formation of empty or loose clusters with very low density. On the other hand, denser clusters are formed for ordered systems with p(s)≈0.065 at s=0.5 and p(s)≈0.38 at s=1.0.
Physical Review E, 2015
The jamming and percolation for two generalized models of random sequential adsorption (RSA) of l... more The jamming and percolation for two generalized models of random sequential adsorption (RSA) of linear k-mers (particles occupying k adjacent sites) on a square lattice are studied by means of Monte Carlo simulation. The classical random sequential adsorption (RSA) model assumes the absence of overlapping of the new incoming particle with the previously deposited ones. The first model LK d is a generalized variant of the RSA model for both k-mers and a lattice with defects. Some of the occupying k adjacent sites are considered as insulating and some of the lattice sites are occupied by defects (impurities). For this model even a small concentration of defects can inhibit percolation for relatively long k-mers. The second model is the cooperative sequential adsorption (CSA) one, where, for each new k-mer, only a restricted number of lateral contacts z with previously deposited k-mers is allowed. Deposition occurs in the case when z ≤ (1 − d)zm where zm = 2(k + 1) is the maximum numbers of the contacts of k-mer, and d is the fraction of forbidden NN contacts. Percolation is observed only at some interval kmin ≤ k ≤ kmax where the values kmin and kmax depend upon the fraction of forbidden contacts d. The value kmax decreases as d increases. A logarithmic dependence of the type log(kmax) = a + bd, where a = −4.03 ± 0.22, b = 4.93 ± 0.57, is obtained.
The European Physical Journal E, 2016
In our model, we simulate an experiment (D.J. Harris, H. Hu, J.C. Conrad, J.A. Lewis, Patterning ... more In our model, we simulate an experiment (D.J. Harris, H. Hu, J.C. Conrad, J.A. Lewis, Patterning colloidal films via evaporative lithography, Phys. Rev. Lett. 98, 148301 (2007)). A thin colloidal sessile droplet is allowed to dry out on a horizontal hydrophilic surface. A mask just above the droplet predominantly allows evaporation from the droplet free surface directly beneath the holes in the mask. We consider one special case, when the holes in the mask are arranged so that the system has rotational symmetry of order m . We use a speculative evaporative flux to mimic the real system. Advection, diffusion, and sedimentation are taken into account. FlexPDE is utilized to solve an advection-diffusion equation using the finite element method. The simulation demonstrates that the colloidal particles accumulate below the holes as the solvent evaporates. Diffusion can reduce this accumulation.
Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been p... more Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been performed to study the percolation behavior of linear kkk-mers (also denoted in the literature as rigid rods, needles, sticks) on two-dimensional square lattices LtimesLL \times LLtimesL with periodic boundary conditions. Percolation phenomena are investigated for anisotropic relaxation random sequential adsorption of linear kkk-mers. Especially, effect of anisotropic placement of the objects on the percolation threshold has been investigated. Moreover, the behavior of percolation probability RL(p)R_L(p)RL(p) that a lattice of size LLL percolates at concentration ppp has been studied in details in dependence on kkk, anisotropy and lattice size LLL. A nonmonotonic size dependence for the percolation threshold has been confirmed in isotropic case. We propose a fitting formula for percolation threshold pc=a/kalpha+blog10k+cp_c = a/k^{\alpha}+b\log_{10} k+ cpc=a/kalpha+blog10k+c, where aaa, bbb, ccc, alpha\alphaalpha are the fitting parameters varying with anisotropy. We predict that for large kkk-mers ($k\gtrapprox 1.2\times10^4$) isotropic placed at the lattice, percolation cannot occur even at jamming concentration.
Physical review. E, Statistical, nonlinear, and soft matter physics, 2015
The effect of defects on the percolation of linear k-mers (particles occupying k adjacent sites) ... more The effect of defects on the percolation of linear k-mers (particles occupying k adjacent sites) on a square lattice is studied by means of Monte Carlo simulation. The k-mers are deposited using a random sequential adsorption mechanism. Two models L(d) and K(d) are analyzed. In the L(d) model it is assumed that the initial square lattice is nonideal and some fraction of sites d is occupied by nonconducting point defects (impurities). In the K(d) model the initial square lattice is perfect. However, it is assumed that some fraction of the sites in the k-mers d consists of defects, i.e., is nonconducting. The length of the k-mers k varies from 2 to 256. Periodic boundary conditions are applied to the square lattice. The dependences of the percolation threshold concentration of the conducting sites p(c) vs the concentration of defects d are analyzed for different values of k. Above some critical concentration of defects d(m), percolation is blocked in both models, even at the jamming c...
Procedia Computer Science, 2014
We present our experience to implement a Current Research Information System in the Astrakhan Sta... more We present our experience to implement a Current Research Information System in the Astrakhan State University, Russia. The CRIS covers research information such as publications, funding, projects, and patents. Education, training, professional activity, and expertise are also within the scope of the CRIS. The metadata of research output are stored as a single record, regardless of the number of contributors and their belonging to different divisions. Data linkage associates a research output with contributors and their departments. A faculty fills own profile and links the metadata with co-authors. The more active and responsible users employ the CRIS, the more complete and reliable is information. Some metadata are imported from external data sources, in particular from Russian Science Citation Index. CRIS can generate Statistical Reports, CV's, Publication Lists, ratings, etc. When implementing the system the main problems are not technical but organizational. The bureaucratic obstacles hinder the exchange of information between different sources. The managerial staff does not demonstrate the real interest in getting actual, complete and accurate information about the research outputs. Some of the faculty has rather little computer skills and low interest in filling the database.
Condensed Matter Physics, 2014
This work studies the jamming and percolation of parallel squares in single-cluster growth model.... more This work studies the jamming and percolation of parallel squares in single-cluster growth model. The Leath-Alexandrowicz method was used to grow a cluster from an active seed site. The sites of a square lattice were occupied by addition of the equal size k × k squares (E-problem) or a mixture of k × k and m × m (m ≤ k) squares (M-problem). The larger k ×k squares were assumed to be active (conductive) and the smaller m×m squares were assumed to be blocked (non-conductive). For equal size k × k squares (E-problem) the value of p j = 0.638 ± 0.001 was obtained for the jamming concentration in the limit of k → ∞. This value was noticeably larger than that previously reported for random sequential adsorption model, p j = 0.564 ± 0.002. It was observed that the value of percolation threshold pc (i.e., the ratio of the area of active k × k squares and the total area of k × k squares in the percolation point) increased with increase of k. For mixture of k × k and m × m squares (M-problem) the value of pc increased noticeably with increase of k at fixed value of m and approached 1 at k ≥ 10m. It reflects that percolation of larger active squares in M-problem can be effectively suppressed in the presence of smaller blocked squares.
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2014
ABSTRACT Formation of the ring-like pattern by nano-particles of the desiccated droplet of a lapo... more ABSTRACT Formation of the ring-like pattern by nano-particles of the desiccated droplet of a laponite-based aqueous nanofluid (the well known 'coffee-ring effect') is studied. The temperature was controlled and fixed (T = 300 K). The laponite concentration was controlled and varied in order to investigate its effect on the pattern formation. It was observed that the coffee-ring effect vanishes if concentration of laponite exceeds 5%. A simple model for analysis of colloidal sessile droplet desiccation is proposed. The model describes correctly dynamics of the drying droplet profile and the final shape of the dried film (deposit). The model is based on the mass conservation law and reasonable assumption that deposit (gel phase) prevents the flows.
Technical Physics, 2007
It is shown that, when a drop of a biological fluid dries out on a substrate, diffusion processes... more It is shown that, when a drop of a biological fluid dries out on a substrate, diffusion processes to a great extent suppress the transfer of the salt toward the periphery of the drop by capillary flows and still have a minor effect on the motion of colloid particles.
Technical Physics, 2001
In [1], for computer simulations of salt crystal growth from biological fluids, the so-called τ-m... more In [1], for computer simulations of salt crystal growth from biological fluids, the so-called τ-model was put forward. This model was used to describe the crystal growth under different conditions [1–5]. However, our independent investigation indicates that the conclusions obtained with the τ-model are not confirmed. The effects observed are related to mistakes in the algorithm.
Physics-Uspekhi, 2004
... 10. Variation of the magnetic properties of a protein solution during drying 726 ... The foll... more ... 10. Variation of the magnetic properties of a protein solution during drying 726 ... The following processes are observed in the dehydration of biological fluids. ... This motion is typical of dryingdroplets of solutions, including colloidal ones, and was studied at length in Refs [12 ± 14]. ...
Physics of the Solid State, 1997
ABSTRACT
Physical Review E, 2012
Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been p... more Numerical simulations by means of Monte Carlo method and finite-size scaling analysis have been performed to study the percolation behavior of linear k-mers (also denoted in the literature as rigid rods, needles, sticks) on two-dimensional square lattices L × L with periodic boundary conditions. Percolation phenomena are investigated for anisotropic relaxation random sequential adsorption of linear k-mers. Especially, effect of anisotropic placement of the objects on the percolation threshold has been investigated. Moreover, the behavior of percolation probability RL(p) that a lattice of size L percolates at concentration p has been studied in details in dependence on k, anisotropy and lattice size L. A nonmonotonic size dependence for the percolation threshold has been confirmed in isotropic case. We propose a fitting formula for percolation threshold pc = a/k α + b log 10 k + c, where a, b, c, α are the fitting parameters varying with anisotropy. We predict that for large kmers (k 1.2 × 10 4 ) isotropic placed at the lattice, percolation cannot occur even at jamming concentration.
physica status solidi (b), 1992
ABSTRACT
Ferroelectrics, 1992
ABSTRACT
Ferroelectrics, 1992
ABSTRACT
Ferroelectrics, 1995
ABSTRACT
Journal de Physique IV (Proceedings), 2005
Monte Carlo simulation studies were performed to examine the implications of octahedral cation an... more Monte Carlo simulation studies were performed to examine the implications of octahedral cation antisite disorder for magnetization in the double 1:1 perovskites A2+(B13+{1/2}B25+{1/2}) O{3}: Sr{2}FeMoO{6} (SFMO) and Pb{2}FeNbO{6} (PFN) at finite temperature. The percolation approach was applied at 0 K. We found that about 14.5 % of antisite defects is a critical value for the properties of the 1:1 double perovskites.