Publications in journals ranked by Journal Citation Reports (JCR) 
Publications in other journals ranked by Ministry of Science and Higher Education
Conference publications indexed in the Web of Science Core Collection
Publications in other journals and conference proceedings
Affiliation to IPPT PAN

1.Czerkies M., Korwek Z., Prus W., Kochańczyk M., Jaruszewicz-Błońska J., Tudelska K., Błoński S., Kimmel M., Brasier A.R., Lipniacki T., Cell fate in antiviral response arises in the crosstalk of IRF, NF-κB and JAK/STAT pathways, Nature Communications, ISSN: 2041-1723, DOI: 10.1038/s41467-017-02640-8, Vol.9, pp.493, 2018
Czerkies M., Korwek Z., Prus W., Kochańczyk M., Jaruszewicz-Błońska J., Tudelska K., Błoński S., Kimmel M., Brasier A.R., Lipniacki T., Cell fate in antiviral response arises in the crosstalk of IRF, NF-κB and JAK/STAT pathways, Nature Communications, ISSN: 2041-1723, DOI: 10.1038/s41467-017-02640-8, Vol.9, pp.493, 2018

Abstract:
The innate immune system processes pathogen-induced signals into cell fate decisions. How information is turned to decision remains unknown. By combining stochastic mathematical modelling and experimentation, we demonstrate that feedback interactions between the IRF3, NF-κB and STAT pathways lead to switch-like responses to a viral analogue, poly(I:C), in contrast to pulse-like responses to bacterial LPS. Poly(I:C) activates both IRF3 and NF-κB, a requirement for induction of IFNβ expression. Autocrine IFNβ initiates a JAK/STAT-mediated positive-feedback stabilising nuclear IRF3 and NF-κB in first responder cells. Paracrine IFNβ, in turn, sensitises second responder cells through a JAK/STAT-mediated positive feedforward pathway that upregulates the positive-feedback components: RIG-I, PKR and OAS1A. In these sensitised cells, the ‘live-or-die’ decision phase following poly(I:C) exposure is shorter—they rapidly produce antiviral responses and commit to apoptosis. The interlinked positive feedback and feedforward signalling is key for coordinating cell fate decisions in cellular populations restricting pathogen spread.

Keywords:
cellular signalling networks, innate immunity, regulatory networks, stochastic modelling

2.Glinicki M.A., Antolik A., Gawlicki M., Evaluation of compatibility of neutron-shielding boron aggregates with Portland cement in mortar, CONSTRUCTION AND BUILDING MATERIALS, ISSN: 0950-0618, DOI: 10.1016/j.conbuildmat.2017.12.228, Vol.164, pp.731-738, 2018
Glinicki M.A., Antolik A., Gawlicki M., Evaluation of compatibility of neutron-shielding boron aggregates with Portland cement in mortar, CONSTRUCTION AND BUILDING MATERIALS, ISSN: 0950-0618, DOI: 10.1016/j.conbuildmat.2017.12.228, Vol.164, pp.731-738, 2018

Abstract:
Enhanced neutron radiation shielding capacity of protective structures can be achieved using cement-based composites with boron-containing aggregates. Experimental tests were performed to evaluate the effect of boron aggregates (colemanite, ulexite, borax, boron carbide) and nanosilica on the setting time and hydration heat of cement in mortars using isothermal calorimetry. Boron leaching test from mineral aggregates were performed in water and saturated Ca(OH)2 solution. Cement setting retardation effects were found qualitatively correlated with boron leaching from mineral aggregates. A linear dependence of compressive strength of borated mortars and heat released after 72 h of cement hydration was found. A maximum content of boron compounds in mortar, allowing for a systematical control of setting time, was evaluated

Keywords:
Boron minerals, Cement setting, Colemanite, Early strength, Heat of hydration, Isothermal calorimetry, Leaching, Nanosilica, Neutron shielding, Retardation, Ulexite

3.Kowalczyk-Gajewska K., Maździarz M., Atomistic and mean-field estimates of effective stiffness tensor of nanocrystalline copper, International Journal of Engineering Science, ISSN: 0020-7225, DOI: 10.1016/j.ijengsci.2018.04.004, Vol.129, pp.47-62, 2018
Kowalczyk-Gajewska K., Maździarz M., Atomistic and mean-field estimates of effective stiffness tensor of nanocrystalline copper, International Journal of Engineering Science, ISSN: 0020-7225, DOI: 10.1016/j.ijengsci.2018.04.004, Vol.129, pp.47-62, 2018

Abstract:
The full elasticity tensor for nano-crystalline copper is derived in molecular simulations by performing numerical tests for a set of generated samples of the polycrystalline material. The results are analysed with respect to the anisotropy degree of the overall stiffness tensor resulting from the limited number of grain orientations and their spatial distribution. The dependence of the overall bulk and shear moduli of an isotropized polycrystal on the average grain diameter is analysed. It is found that while the shear modulus decreases with grain size, the bulk modulus shows negligible dependence on the grain diameter and is close to the bulk modulus of a single crystal. A closed-form mean-field model of effective elastic properties for a bulk nano-grained polycrystal with cubic grains, i.e. made of a material with cubic symmetry, is formulated. In the model all parameters are based on the data for a single crystal and on the averaged grain size without any need for additional fitting. It is shown that the proposed model provides predictions of satisfactory qualitative and quantitative agreement with atomistic simulations.

Keywords:
Molecular statics, Elasticity, Polycrystal, Effective medium, Nano-crystalline copper

4.Rojek J., Zubelewicz A., Madan N., Nosewicz S., The discrete element method with deformable particles, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, ISSN: 0029-5981, DOI: 10.1002/nme.5767, pp.1-33, 2018
Rojek J., Zubelewicz A., Madan N., Nosewicz S., The discrete element method with deformable particles, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, ISSN: 0029-5981, DOI: 10.1002/nme.5767, pp.1-33, 2018

Abstract:
This work presents a new original formulation of the discrete element method (DEM) with deformable cylindrical particles. Uniform stress and strain fields are assumed to be induced in the particles under the action of contact forces. Particle deformation obtained by strain integration is taken into account in the evaluation of interparticle contact forces. The deformability of a particle yields a nonlocal contact model, it leads to the formation of new contacts, it changes the distribution of contact forces in the particle assembly, and it affects the macroscopic response of the particulate material. A numerical algorithm for the deformable DEM (DDEM) has been developed and implemented in the DEM program DEMPack. The new formulation implies only small modifications of the standard DEM algorithm. The DDEM algorithm has been verified on simple examples of an unconfined uniaxial compression of a rectangular specimen discretized with regularly spaced equal bonded particles and a square specimen represented with an irregular configuration of nonuniform-sized bonded particles. The numerical results have been verified by a comparison with equivalent finite elementmethod results and available analytical solutions. The micro-macro relationships for elastic parameters have been obtained. The results have proved to have enhanced the modeling capabilities of the DDEM with respect to the standard DEM.

Keywords:
average stress, deformable particles, discrete element method, elastic constants, micro-macro relationships, nonlocal contact model

5.Tůma K., Stupkiewicz S., Petryk H., Rate-independent dissipation in phase-field modelling of displacive transformations, JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS, ISSN: 0022-5096, DOI: 10.1016/j.jmps.2018.02.007, Vol.114, pp.117-142, 2018
Tůma K., Stupkiewicz S., Petryk H., Rate-independent dissipation in phase-field modelling of displacive transformations, JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS, ISSN: 0022-5096, DOI: 10.1016/j.jmps.2018.02.007, Vol.114, pp.117-142, 2018

Abstract:
In this paper, rate-independent dissipation is introduced into the phase-field framework for modelling of displacive transformations, such as martensitic phase transformation and twinning. The finite-strain phase-field model developed recently by the present authors is here extended beyond the limitations of purely viscous dissipation. The variational formulation, in which the evolution problem is formulated as a constrained minimization problem for a global rate-potential, is enhanced by including a mixed-type dissipation potential that combines viscous and rate-independent contributions. Effective computational treatment of the resulting incremental problem of non-smooth optimization is developed by employing the augmented Lagrangian method. It is demonstrated that a single Lagrange multiplier field suffices to handle the dissipation potential vertex and simultaneously to enforce physical constraints on the order parameter. In this way, the initially non-smooth problem of evolution is converted into a smooth stationarity problem. The model is implemented in a finite-element code and applied to solve two- and three-dimensional boundary value problems representative for shape memory alloys

Keywords:
Phase-field method, Microstructure, Martensite, Twinning, Non-smooth optimization

6.Maździarz M., Mrozek A., Kuś W., Burczyński T., Anisotropic-Cyclicgraphene: A New Two-Dimensional Semiconducting Carbon Allotrope, Materials, ISSN: 1996-1944, DOI: 10.3390/ma11030432, Vol.11, No.3, pp.432, 2018
Maździarz M., Mrozek A., Kuś W., Burczyński T., Anisotropic-Cyclicgraphene: A New Two-Dimensional Semiconducting Carbon Allotrope, Materials, ISSN: 1996-1944, DOI: 10.3390/ma11030432, Vol.11, No.3, pp.432, 2018

Abstract:
A potentially new, single-atom thick semiconducting 2D-graphene-like material, called
Anisotropic-cyclicgraphene , has been generated by the two stage searching strategy linking molecular
and ab initio approach. The candidate was derived from the evolutionary-based algorithm and
molecular simulations was then profoundly analysed using first-principles density functional theory
from the structural, mechanical, phonon, and electronic properties point of view. The proposed
polymorph of graphene (rP16-P1m1) is mechanically, dynamically, and thermally stable and can
achieve semiconducting with a direct band gap of 0.829 eV.

Keywords:
carbon; graphene; graphyne; ab initio calculations; Semiconductors

7.Pieczyska E.A., Maj M., Golasiński K., Staszczak M., Furuta T., Kuramoto S., Thermomechanical Studies of Yielding and Strain Localization Phenomena of Gum Metal under Tension, Materials, ISSN: 1996-1944, DOI: 10.3390/ma11040567, Vol.11, No.567, pp.1-13, 2018
Pieczyska E.A., Maj M., Golasiński K., Staszczak M., Furuta T., Kuramoto S., Thermomechanical Studies of Yielding and Strain Localization Phenomena of Gum Metal under Tension, Materials, ISSN: 1996-1944, DOI: 10.3390/ma11040567, Vol.11, No.567, pp.1-13, 2018

Abstract:
This paper presents results of investigation of multifunctional -Ti alloy Gum Metal subjected to tension at various strain rates. Digital image correlation was used to determine strain distributions and stress-strain curves, while infrared camera allowed for us to obtain the related temperature characteristics of the specimen during deformation. The mechanical curves completed by the temperature changes were applied to analyze the subsequent stages of the alloy loading. Elastic limit, recoverable strain, and development of the strain localization were studied. It was found that the maximal drop in temperature, which corresponds to the yield limit of solid materials, was referred to a significantly lower strain value in the case of Gum Metal in contrast to its large recoverable strain. The temperature increase proves a dissipative character of the process and is related to presence of w and a” phases induced during the alloy fabrication and their exothermic phase transformations activated under loading. During plastic deformation, both the strain and temperature distributions demonstrate that strain localization for higher strain rates starts nucleating just after the yield limit leading to specimen necking and rupture. Macroscopically, it is exhibited as softening of the stress-strain curve in contrast to the strain hardening observed at lower strain rates.

Keywords:
gum metal, yield limit, thermomechanical coupling, infrared thermography, digital image correlation, strain localization

8.Suchorzewski J., Korol E., Tejchman J., Mróz Z., Experimental study of shear strength and failure mechanisms in RC beams scaled along height or length, ENGINEERING STRUCTURES, ISSN: 0141-0296, DOI: 10.1016/j.engstruct.2017.12.003, Vol.157, pp.203-223, 2018
Suchorzewski J., Korol E., Tejchman J., Mróz Z., Experimental study of shear strength and failure mechanisms in RC beams scaled along height or length, ENGINEERING STRUCTURES, ISSN: 0141-0296, DOI: 10.1016/j.engstruct.2017.12.003, Vol.157, pp.203-223, 2018

Abstract:
The paper presents results of laboratory experiments carried out on longitudinally reinforced concrete beams subjected to four-point bending. Beams of separately varying height and length were analyzed to investigate the size effect on nominal strength and post-critical brittleness. Beams were scaled in the height direction in the first test series and in the length direction in the second series. Due to lack of geometrical similarity, different failure mechanisms were exhibited. Load-deflection diagrams and crack paths were registered during experiments. The digital image correlation technique was applied to visualize strain localization on the concrete surface. The crack opening and crack slip displacements were also measured. The beam response was characterized by two non-dimensional parameters ηa = a/D and ηb = b/D defined as the ratios of shear and bending spans to the beam depth D assumed as the size parameter and the reinforcement position parameter ηc = c′/D. Two major failure mechanisms were observed: flexural failure in the central beam zone combined with plastic yielding of the reinforcement and the diagonal shear crack failure in external shear zones. Two distinct modes of shear failure can be specified depending on the dominance of crack opening or crack closure contact zones. Two different effective stresses associated with failure mechanisms were defined to specify the beam strength’s dependence on ηa, ηb, ηc and D. Some analytical formulae specifying the critical shear stress dependence on ηa, ηc and strengths ratio of reinforcement and concrete were presented at the end of paper and compared with experimental data.

Keywords:
Concrete beams, Longitudinal reinforcement, Four-point bending, Failure modes, Height or length variation, Size effect

9.Bigoni D., Bordignon N., Piccolroaz A., Stupkiewicz S., Bifurcation of elastic solids with sliding interfaces, PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, ISSN: 1364-5021, DOI: 10.1098/rspa.2017.0681, Vol.474, pp.20170681-1-21, 2018
Bigoni D., Bordignon N., Piccolroaz A., Stupkiewicz S., Bifurcation of elastic solids with sliding interfaces, PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, ISSN: 1364-5021, DOI: 10.1098/rspa.2017.0681, Vol.474, pp.20170681-1-21, 2018

Abstract:
Lubricated sliding contact between soft solids is an interesting topic in biomechanics and for the design of small-scale engineering devices. As a model of this mechanical set-up, two elastic nonlinear solids are considered jointed through a frictionless and bilateral surface, so that continuity of the normal component of the Cauchy traction holds across the surface, but the tangential component is null. Moreover, the displacement can develop only in a way that the bodies in contact do neither detach, nor overlap. Surprisingly, this finite strain problem has not been correctly formulated until now, so this formulation is the objective of the present paper. The incremental equations are shown to be non-trivial and different from previously (and erroneously) employed conditions. In particular, an exclusion condition for bifurcation is derived to show that previous formulations based on frictionless contact or ‘spring-type’ interfacial conditions are not able to predict bifurcations in tension, while experiments—one of which, ad hoc designed, is reported—show that these bifurcations are a reality and become possible when the correct sliding interface model is used. The presented results introduce a methodology for the determination of bifurcations and instabilities occurring during lubricated sliding between soft bodies in contact

Keywords:
frictionless contact, large strains, nonlinear elasticity

10.Enayati M.S., Behzad T., Sajkiewicz P., Rafienia M., Bagheri R., Ghasemi-Mobarakeh L., Kołbuk D., Pahlevanneshan Z., Bonakdar S.H., Development of electrospun poly (vinyl alcohol)-based bionanocomposite scaffolds for bone tissue engineering, Journal of Biomedical Materials Research Part A, ISSN: 1549-3296, DOI: 10.1002/jbm.a.36309, Vol.106, No.4, pp.1111-1120, 2018
Enayati M.S., Behzad T., Sajkiewicz P., Rafienia M., Bagheri R., Ghasemi-Mobarakeh L., Kołbuk D., Pahlevanneshan Z., Bonakdar S.H., Development of electrospun poly (vinyl alcohol)-based bionanocomposite scaffolds for bone tissue engineering, Journal of Biomedical Materials Research Part A, ISSN: 1549-3296, DOI: 10.1002/jbm.a.36309, Vol.106, No.4, pp.1111-1120, 2018

Abstract:
The article is focused on the role of nanohydroxy apatite (nHAp) and cellulose nanofibers (CNFs) as fillers in the electrospun poly (vinyl alcohol) (ES-PVA) nanofibers for bone tissue engineering (TE). Fibrous scaffolds of PVA, PVA/nHAp (10 wt.%), and PVA/nHAp(10 wt.%)/CNF(3 wt.%) were successfully fabricated and characterized. Tensile test on electrospun PVA/nHAp10 and PVA/nHAp10/CNF3 revealed a three-fold and seven-fold increase in modulus compared with pure ES-PVA (45.45 ± 4.77). Although, nanofiller loading slightly reduced the porosity percentage, all scaffolds had porosity higher than 70%. In addition, contact angle test proved the great hydrophilicity of scaffolds. The presence of fillers reduced in vitro biodegradation rate in PBS while accelerates biomineralization in simulated body fluid (SBF). Furthermore, cell viability, cell attachment, and functional activity of osteoblast MG-63 cells were studied on scaffolds showing higher cellular activity for scaffolds with nanofillers. Generally, the obtained results confirm that the 3-componemnt fibrous scaffold of PVA/nHAp/CNF has promising potential in hard TE.

Keywords:
electrospinning, PVA bionanocomposites, scaffolds, bone tissue engineering, cell culture

11.Jarecki L., Pecherski R.B., Kinetics of oriented crystallization of polymers in the linear stress-orientation range in the series expansion approach , Express Polymer Letters, ISSN: 1788-618X, DOI: 10.3144/expresspolymlett/2018.29, Vol.12, No.4, pp.330-348, 2018
Jarecki L., Pecherski R.B., Kinetics of oriented crystallization of polymers in the linear stress-orientation range in the series expansion approach , Express Polymer Letters, ISSN: 1788-618X, DOI: 10.3144/expresspolymlett/2018.29, Vol.12, No.4, pp.330-348, 2018

Abstract:
An analytical formula is derived for the oriented crystallization coefficient governing kinetics of oriented crystallization under uniaxial amorphous orientation in the entire temperature range. A series expansion approach is applied to the free energy of crystallization in the Hoffman-Lauritzen kinetic model of crystallization at accounting for the entropy of orientation of the amorphous chains. The series expansion coefficients are calculated for systems of Gaussian chains in linear stress-orientation range. Oriented crystallization rate functions are determined basing on the ‘proportional expansion’ approach proposed by Ziabicki in the steady-state limit. Crystallization kinetics controlled by separate predetermined and sporadic primary nucleation is considered, as well as the kinetics involving both nucleation mechanisms potentially present in oriented systems. The involvement of sporadic nucleation in the transformation kinetics is predicted to increase with increasing amorphous orientation. Example computations illustrate the dependence of the calculated functions on temperature and amorphous orientation, as well as qualitative agreement of the calculations with experimental results.

Keywords:
modeling and simulation, kinetics of oriented crystallization, amorphous orientation, sporadic nucleation, predetermined nucleation

12.Maj J., Basista M., Węglewski W., Bochenek K., Strojny-Nędza A., Naplocha K., Panzner T., Tatarkova M., Fiori F., Effect of microstructure on mechanical properties and residual stresses in interpenetrating aluminum-alumina composites fabricated by squeeze casting, MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, ISSN: 0921-5093, DOI: 10.1016/j.msea.2017.12.091, Vol.715, pp.154-162, 2018
Maj J., Basista M., Węglewski W., Bochenek K., Strojny-Nędza A., Naplocha K., Panzner T., Tatarkova M., Fiori F., Effect of microstructure on mechanical properties and residual stresses in interpenetrating aluminum-alumina composites fabricated by squeeze casting, MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, ISSN: 0921-5093, DOI: 10.1016/j.msea.2017.12.091, Vol.715, pp.154-162, 2018

Abstract:
Aluminum-alumina composites with interpenetrating network structure are interesting structural materials due to their high resistance to elevated temperature and frictional wear, good heat conductivity, enhanced mechanical strength and fracture toughness. In this paper aluminum-alumina bulk composites and FGMs are manufactured by pressure infiltration of porous alumina preforms with molten aluminium alloy (EN AC-44200). Influence of the interpenetrating microstructure on the macroscopic bending strength, fracture toughness, hardness and heat conduction is examined. Special focus is on processing-induced thermal residual stresses in aluminium-alumina composites due to their potentially detrimental effects on material performance in structural elements under in-service conditions. The residual stresses are measured experimentally in the ceramic phase by neutron diffraction and simulated numerically using a micro-CT based Finite Element model, which takes into account the actual interpenetrating microstructure of the composite. The model predictions for two different volume fractions of alumina agree fairly well with the neutron diffraction measurements

Keywords:
A. stress measurements, X-ray analysis, finite element analysis, B. composites, C. casting methods

13.Kopeć M., Wang K., Politis D.J., Wang Y., Wang L., Lin J., Formability and microstructure evolution mechanisms of Ti6Al4V alloy during a novel hot stamping process, MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, ISSN: 0921-5093, DOI: 10.1016/j.msea.2018.02.038, pp.1-20, 2018
Kopeć M., Wang K., Politis D.J., Wang Y., Wang L., Lin J., Formability and microstructure evolution mechanisms of Ti6Al4V alloy during a novel hot stamping process, MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, ISSN: 0921-5093, DOI: 10.1016/j.msea.2018.02.038, pp.1-20, 2018

Abstract:
A novel hot stamping process for Ti6Al4V alloy using cold forming tools and a hot blank was presented in this paper. The formability of the material was studied through uniaxial tensile tests at temperatures ranging from 600 to 900 °C and strain rates ranging from 0.1 to 5 s-1. An elongation ranging from 30% to 60% could be achieved at temperatures ranging from 750 to 900°C respectively. The main microstructure evolution mechanisms varied with the deformation temperature, including recovery, phase transformation and recrystallization. The hardness of the material after deformation first decreased with the temperature due to recovery, and subsequently increased mainly due to the phase transformation. During the hot stamping tests, qualified parts could be formed successfully at heating temperatures ranging from 750 to 850°C. The forming failed at lower temperatures due to the limited ductility of the material. At temperatures higher than 900°C, extensive phase transformation of α to β occurred during the heating. During the transfer and forming, the temperature dropped significantly which led to the formation of transformed β, reduction of the formability and subsequent failure. The post-form hardness distribution demonstrated the same tendency as that after uniaxial tensile tests.

Keywords:
titanium alloys, Ti6Al4V, hot stamping, microstructure

14.Chrzanowska-Giżyńska J., Denis P., Hoffman J., Giżyński M., Mościcki T., Garbiec D., Szymański Z., Tungsten borides layers deposited by a nanosecond laser pulse, SURFACE AND COATINGS TECHNOLOGY, ISSN: 0257-8972, DOI: 10.1016/j.surfcoat.2017.12.040, Vol.335, pp.181-187, 2018
Chrzanowska-Giżyńska J., Denis P., Hoffman J., Giżyński M., Mościcki T., Garbiec D., Szymański Z., Tungsten borides layers deposited by a nanosecond laser pulse, SURFACE AND COATINGS TECHNOLOGY, ISSN: 0257-8972, DOI: 10.1016/j.surfcoat.2017.12.040, Vol.335, pp.181-187, 2018

Abstract:
Tungsten borides belong to the group of potentially superhard materials which hardness could be compared to cubic boron nitride and diamond. However, difficulty in fabrication of single phase material using conventional methods is the main drawback of this group of ceramics. In order to overcome this problem material can be deposited as a thin layer e.g. in the pulsed laser deposition process. In this paper, the effect of laser wavelength and energy density of nanosecond Nd:YAG laser on the WBx-type layers were analyzed using wavelengths 355 and 1064 nm with the energy density of laser beam from 1.7 to 5 J/cm2 and from 1.7 to 9.3 J/cm2, respectively. The WB2.5 and WB4.5 targets synthesized in Spark Plasma Sintering process were used and the layers were deposited onto Si (100) substrate heated to a temperature of 570 °C. Layers' microstructure were analyzed using X-ray Diffraction and scanning electron microscope equipped with energy dispersive X-ray spectrometer. Change of laser wavelength and energy density resulted in variations of the chemical composition and morphology of deposited layers. Finally, W2B-βWB, αWB-WB-WB3 and WB3, and boron layers were deposited wherein WB3 structure is formed in a wide range of laser fluences and at both investigated wavelength. Next, WB3 layers were investigated in the indentation test at a load of 5–30 mN and its hardness was up to 50 ± 10 GPa

Keywords:
Pulsed laser deposition, Super-hard materials, Tungsten borides, Tungsten triboride

15.Balevičius R., Mróz Z., Modeling of combined slip and finite sliding at spherical grain contacts, GRANULAR MATTER, ISSN: 1434-5021, DOI: 10.1007/s10035-017-0778-6, Vol.10, pp.1-27, 2018
Balevičius R., Mróz Z., Modeling of combined slip and finite sliding at spherical grain contacts, GRANULAR MATTER, ISSN: 1434-5021, DOI: 10.1007/s10035-017-0778-6, Vol.10, pp.1-27, 2018

Abstract:
The present paper is aimed at developing the analytical description of the interaction of two contacting spheres for several classes of slip and sliding trajectories, typical in the experimental testing. The analysis accounts for memory effects in the slip regime and configurational effects in the sliding regime, expressed in terms of an active loading surface and memory surfaces within the space of contact forces. Analytical relations for contact response are derived for linear and piecewise-linear motion trajectories of the sphere. The problem of multiple contact interaction of the sphere moving over the regularly packed granular bed is also considered analytically. It is demonstrated that the dual contact activation-separation processes occur within the combined slip–sliding modes, essentially affecting the distribution of contact tractions. The results obtained are relevant for the class of contact problems requiring analysis of interaction of slip and sliding displacements, in particular in testing grain contact interaction aimed at specification of elastic, frictional and wear parameters.

Keywords:
Sphere–sphere contact, Memory rules, Slip and sliding, Displacement and force control, Monotonic and reciprocal sliding, Friction, Granular bed

16.Krajewski M., Brzozka K., Tokarczyk M., Kowalski G., Lewinska S., Slawska-Waniewska A., Lin W.S., Lin H.M., Impact of thermal oxidation on chemical composition and magnetic properties of iron nanoparticles, Journal of Magnetism and Magnetic Materials, ISSN: 0304-8853, DOI: 10.1016/j.jmmm.2018.03.047, Vol.458, pp.346-354, 2018
Krajewski M., Brzozka K., Tokarczyk M., Kowalski G., Lewinska S., Slawska-Waniewska A., Lin W.S., Lin H.M., Impact of thermal oxidation on chemical composition and magnetic properties of iron nanoparticles, Journal of Magnetism and Magnetic Materials, ISSN: 0304-8853, DOI: 10.1016/j.jmmm.2018.03.047, Vol.458, pp.346-354, 2018

Abstract:
The main objective of this work is to study the influence of thermal oxidation on the chemical composition and magnetic properties of iron nanoparticles which were manufactured in a simple chemical reduction of Fe3+ ions coming from iron salt with sodium borohydride. The annealing processing was performed in an argon atmosphere containing the traces of oxygen to avoid spontaneous oxidation of iron at temperatures ranging from 200 °C to 800 °C. The chemical composition and magnetic properties of as-prepared and thermally-treated nanoparticles were determined by means of X-ray diffractometry, Raman spectroscopy, Mössbauer spectroscopy and vibrating sample magnetometry. Due to the magnetic interactions, the investigated iron nanoparticles tended to create the dense aggregates which were difficult to split even at low temperatures. This caused that there was no empty space between them, which led to their partial sintering at elevated temperatures. These features hindered their precise morphological observations using the electron microscopy techniques. The obtained results show that the annealing process up to 800 °C resulted in a progressive change in the chemical composition of as-prepared iron nanoparticles which was associated with their oxidation. As a consequence, their magnetic properties also depended on the annealing temperature. For instance, considering the values of saturation magnetization, its highest value was recorded for the as-prepared nanoparticles at 1 T and it equals 149 emu/g, while the saturation point for nanoparticles treated at 600 °C and higher temperatures was not reached even at the magnetic field of about 5 T. Moreover, a significant enhancement of coercivity was observed for the iron nanoparticles annealed over 600 °C.

Keywords:
Chemical composition, Chemical reduction, Iron nanoparticle, Magnetic properties, Oxidation

17.Mościcki T., Hoffman J., Szymański Z., Laser ablation in an ambient gas: Modelling and experiment, JOURNAL OF APPLIED PHYSICS, ISSN: 0021-8979, DOI: 10.1063/1.5010413, Vol.123, pp.083305-1-083305-8, 2018
Mościcki T., Hoffman J., Szymański Z., Laser ablation in an ambient gas: Modelling and experiment, JOURNAL OF APPLIED PHYSICS, ISSN: 0021-8979, DOI: 10.1063/1.5010413, Vol.123, pp.083305-1-083305-8, 2018

Abstract:
The laser ablation of graphite in ambient argon is studied both experimentally and theoretically in conditions corresponding to the initial conditions of carbon nanotube synthesis by the laser vaporization method. The results of the experiment show that the maximum plasma temperature of 24 000 K is reached 25 ns after the beginning of the laser pulse and decreases to about 4000–4500 K after 10 μs. The maximum electron density of 8 × 1025 m−3 is reached 15 ns from the beginning of the laser pulse. The hydrodynamic model applied shows comparable plasma temperatures and electron densities. The model also replicates well a shock wave and plume confinement—intrinsic features of supersonic flow of the ablated plume in an ambient gas. The results show that the theoretical model can be used to simulate nanosecond laser ablation in an ambient gas from the beginning of the process up to several microseconds.

18.Schabowicz K., Jóźwiak-Niedźwiedzka D., Ranachowski Z., Kudela Jr. S., Dvorak T., Microstructural characterization of cellulose fibres in reinforced cement boards, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1016/j.acme.2018.01.018, Vol.18, No.4, pp.1068-1078, 2018
Schabowicz K., Jóźwiak-Niedźwiedzka D., Ranachowski Z., Kudela Jr. S., Dvorak T., Microstructural characterization of cellulose fibres in reinforced cement boards, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1016/j.acme.2018.01.018, Vol.18, No.4, pp.1068-1078, 2018

Abstract:
The microscopic analysis of the different cellulose fibre cement composites is presented. The observations of the fibres in optical microscope in transmitted light and in scanning electron microscope are described. The micro computed tomography (micro-CT) and SEM were used to determine the distribution of the fibres in the matrix. The investigated fibre cement boards were produced by extrusion process and panels were cured in natural conditions. The main goal of the research was application of different microscopic methods to analyze the fibres distribution as a result of a different methods of their production. Micro-CT was used for 3D visualization of fibres distribution in three different fibre cement boards. It was possible to determine the average diameter of the fibres and their concentration using the high-resolution mode of micro-CT scanning procedure. Finally, a procedure which can be applied as a useful tool for analysis of the different procedures used in production of fibre cement boards is described. This procedure can be successfully used in the quality control system of cellulose fibre distribution in cement composites

Keywords:
Cellulose fibre reinforced cement boards, Microstructure, Fibre distribution, X-ray microtomography, SEM-EDS analysis

19.Mucha M., Wcisło B., Pamin J., Kowalczyk-Gajewska K., Instabilities in membrane tension: Parametric study for large strain thermoplasticity, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1016/j.acme.2018.01.008, Vol.18, No.4, pp.1055-1067, 2018
Mucha M., Wcisło B., Pamin J., Kowalczyk-Gajewska K., Instabilities in membrane tension: Parametric study for large strain thermoplasticity, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1016/j.acme.2018.01.008, Vol.18, No.4, pp.1055-1067, 2018

Abstract:
This paper deals with the numerical analysis of localized deformation for a rectangular plate in membrane tension, modelled with large strain thermoplasticity. The aim is to determine the influence of selected factors on the localization phenomena, which can result from geometrical, material, and thermal softening. Two types of boundary conditions are considered: plane stress and plane strain, as well as two yield functions, Huber–Mises–Hencky and Burzyński–Drucker–Prager, with selected values of friction angle. First, isothermal conditions are considered and next, a conductive case with thermal softening is studied. Moreover, three types of plastic behaviour are analysed: strain hardening (with different values of hardening modulus), ideal plasticity, and strain softening. Numerical tests, performed using AceGen/FEM packages, are carried out for the rectangular plate under tension with an imperfection, using three finite element discretizations. The results for plane strain in the isothermal model show that with the decrease of linear hardening modulus, we can observe stronger mesh sensitivity, while for plane stress, mesh sensitivity is visible for all cases. Furthermore, for the thermomechanical model the results also depend on the mesh density due to insufficient heat conduction regularization

Keywords:
Thermoplasticity, Large strains, Strain localization, Parametric study

20.Lumelskyj D., Rojek J., Tkocz M., Detection of strain localization in numerical simulation of sheet metal forming, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1016/j.acme.2017.08.004, Vol.18, No.2, pp.490-499, 2018
Lumelskyj D., Rojek J., Tkocz M., Detection of strain localization in numerical simulation of sheet metal forming, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1016/j.acme.2017.08.004, Vol.18, No.2, pp.490-499, 2018

Abstract:
This paper presents an investigation on the detection of strain localization in numerical simulation of sheet metal forming. Two methods to determine the onset of localized necking have been compared. The first criterion, newly implemented in this work, is based on the analysis of the through-thickness thinning (through-thickness strain) and its first time derivative in the most strained zone. The limit strain in the second method, studied in the authors’ earlier works, is determined by the maximum of the strain acceleration. The limit strains have been determined for different specimens undergoing deformation at different strain paths covering the whole range of the strain paths typical for sheet forming processes. This has allowed to construct numerical forming limit curves (FLCs). The numerical FLCs have been compared with the experimental one. Mesh sensitivity analysis for these criteria has been performed for the selected specimens. It has been shown that the numerical FLC obtained with the new criterion predicts formability limits close to the experimental results so this method can be used as a potential alternative tool to determine formability in standard finite element simulations of sheet forming processes.

Keywords:
Sheet forming, Formability, Forming limit diagram, Strain localization, Numerical simulation

21.Radziejewska J., Sarzyński A., Strzelec M., Diduszko R., Hoffman J., Evaluation of residual stress and adhesion of Ti and TiN PVD films by laser spallation technique, OPTICS & LASER TECHNOLOGY, ISSN: 0030-3992, DOI: 10.1016/j.optlastec.2018.02.014, Vol.104, pp.140-147, 2018
Radziejewska J., Sarzyński A., Strzelec M., Diduszko R., Hoffman J., Evaluation of residual stress and adhesion of Ti and TiN PVD films by laser spallation technique, OPTICS & LASER TECHNOLOGY, ISSN: 0030-3992, DOI: 10.1016/j.optlastec.2018.02.014, Vol.104, pp.140-147, 2018

Abstract:
The laser spallation technique was applied for measurement of residual stress and adhesion of thin films. Two films of different properties, ductile and soft Ti, and hard and brittle TiN, were studied. The films were produced on 304 steel substrate by PVD method. The residual stress value obtained by laser spallation technique LST were compared with stress value from X-ray diffraction method. Good agreement of stress values measured by both methods was attained. Additionally, the interface strength of the films was tested by laser adhesion spallation technique LASAT with use of VISAR system. It was shown that shock wave induced by a nanosecond laser pulse adequately determines properties of PVD thin films on metal substrate

Keywords:
Laser spallation technique, Residual stress, Adhesion, Thin layer, PVD, VISAR system

22.Małolepszy A., Błoński S., Chrzanowska-Giżyńska J., Wojasiński M., Płociński T., Stobiński L., Szymański Z., Fluorescent carbon and graphene oxide nanoparticles synthesized by the laser ablation in liquid, APPLIED PHYSICS A-MATERIALS SCIENCE AND PROCESSING, ISSN: 0947-8396, DOI: 10.1007/s00339-018-1711-5, pp.124-282, 2018
Małolepszy A., Błoński S., Chrzanowska-Giżyńska J., Wojasiński M., Płociński T., Stobiński L., Szymański Z., Fluorescent carbon and graphene oxide nanoparticles synthesized by the laser ablation in liquid, APPLIED PHYSICS A-MATERIALS SCIENCE AND PROCESSING, ISSN: 0947-8396, DOI: 10.1007/s00339-018-1711-5, pp.124-282, 2018

Abstract:
The results of synthesis of the fluorescent carbon dots (CDots) from graphite target and reduced graphene oxide (rGO) nanoparticles performed by the nanosecond laser ablation in polyethylene glycol 200 (PEG200) are shown. Two-step laser irradiation (first graphite target, next achieved suspension) revealed a very effective production of CDots. However, the ablation in PEG appeared to be effective with 1064 nm laser pulse in contrast to the ablation with 355 nm laser pulse. In the case of rGO nanoparticles similar laser irradiation procedure was less efficient. In both cases, received nanoparticles exhibited strong, broadband photoluminescence with a maximum dependent on the excitation wavelength. The size distribution for obtained CDots was evaluated using the DLS technique and HRTEM images. The results from both methods show quite good agreement in nanoparticle size estimation although the DLS method slightly overestimates nanoparticle’s diameter

23.Rokicki G., Kowalczyk T., Kaczorowski M., Sześcioczłonowe węglany cykliczne jako modyfikatory żywic epoksydowych, POLIMERY, ISSN: 0032-2725, DOI: 10.14314/polimery.2018.2.2, Vol.63, No.2, pp.90-101, 2018
Rokicki G., Kowalczyk T., Kaczorowski M., Sześcioczłonowe węglany cykliczne jako modyfikatory żywic epoksydowych, POLIMERY, ISSN: 0032-2725, DOI: 10.14314/polimery.2018.2.2, Vol.63, No.2, pp.90-101, 2018

Abstract:
Przedstawiono metodę modyfikacji żywic epoksydowych biscyklicznymi węglanami sześcioczłonowymi. Wykazano, że katalizowana kwasami Lewisa reakcja oksiranów z sześcioczłonowymi węglanami cyklicznymi przebiega głównie z wytworzeniem spiroortowęglanu pięcio-sześcioczłonowego. W jej wyniku powstają poli(etero-węglany), polietery i pięcioczłonowe węglany cykliczne. W niskiej temperaturze reakcja może ulec zahamowaniu na etapie spiroortowęglanu. Wykazano, że żywice epoksydowe zmodyfikowane dodatkiem 10 % mas. oligomeru uretanowego, zakończonego sześcioczłonowymi cyklicznymi węglanami lub biscyklicznym węglanem zawierającym resztę glikolu tri(oksyetylenowego), charakteryzują się udarnością o 66–83 % większą niż żywica niemodyfikowana, przy zachowanym poziomie wartości pozostałych cech wytrzymałościowych.

Keywords:
biscykliczne węglany sześcioczłonowe, modyfikacja żywicy epoksydowej, cykliczny węglan jako aktywny rozcieńczalnik, kationowa kopolimeryzacja oksiranów z sześcioczłonowymi cyklicznymi węglanami, polimeryzacja z otwarciem pierścienia

24.Kruk A., Gadomska-Gajadhur A., Dulnik J., Rykaczewska I., Ruśkowski P., Sebai A., Synoradzki L., Ocena właściwości użytkowych rusztowań komórkowych o strukturze gąbczastej oraz wzrostu na nich fibroblastów, POLIMERY, ISSN: 0032-2725, DOI: 10.14314/polimery.2018.4.3, Vol.63, No.4, pp.18-22, 2018
Kruk A., Gadomska-Gajadhur A., Dulnik J., Rykaczewska I., Ruśkowski P., Sebai A., Synoradzki L., Ocena właściwości użytkowych rusztowań komórkowych o strukturze gąbczastej oraz wzrostu na nich fibroblastów, POLIMERY, ISSN: 0032-2725, DOI: 10.14314/polimery.2018.4.3, Vol.63, No.4, pp.18-22, 2018

Abstract:
Zbadano wpływ dodatku ciekłych prekursorów porów na morfologię, porowatość i właściwości mechaniczne polilaktydowych rusztowań komórkowych. Rusztowania otrzymano metodą mokrej inwersji faz w wariancie freeze extraction. Oceniono cytotoksyczność wybranych rusztowań w stosunku do fibroblastów mysich oraz ich przydatność do hodowli komórkowych. Wykazano, że dodatek prekursora porów dopolilaktydu korzystnie zmienia morfologię wytworzonych rusztowań, jednocześnie pogarszając ich wytrzymałość mechaniczną. Stwierdzono, że polilaktydowe rusztowania komórkowe z powodzeniem mogą być wykorzystywane do hodowli komórkowych.

Keywords:
usztowania komórkowe, polilaktyd, hodowle komórkowe, fibroblasty

25.Ustrzycka A., Szuwalski K., Annular rotating disks optimal with respect to mixed creep rupture, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl.56.1.57, Vol.56, No.1, pp.57-69, 2018
Ustrzycka A., Szuwalski K., Annular rotating disks optimal with respect to mixed creep rupture, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl.56.1.57, Vol.56, No.1, pp.57-69, 2018

Abstract:
Optimal shapes in the class of polynomial functions for rotating annular disks with respect to the mixed creep rupture time are found. Two effects leading to damage: diminishing of transversal dimensions and growth of micro-cracks are simultaneously taken into account. The first of them requires the finite strain analysis, the latter is described by Kachanov’s evolution equation. Behaviour of the material is described by nonlinear Norton’s law, generalized for true stresses and logarithmic strains, and the shape change law in form of similarity of true stresses and logarithmic strains deviators. For optimal shapes of the disk, changes of geometry and a continuity function are presented. The theoretical considerations based on the perception of the structural components as some highlighted objects with defined properties is presented

Keywords:
annular disk, mixed creep rupture, optimal design

26.Frąś L.J., Pęcherski R.B., Modified split hopkinson pressure bar for investigations of dynamic behaviour of magnetorheological materials, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl.56.1.323, Vol.56, No.1, pp.323-328, 2018
Frąś L.J., Pęcherski R.B., Modified split hopkinson pressure bar for investigations of dynamic behaviour of magnetorheological materials, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl.56.1.323, Vol.56, No.1, pp.323-328, 2018

Abstract:
The magnetorheological fluid is a functional material that is changing its rheological properties and finally solidifies in a magnetic field. The dynamic behaviour, tested with the use of the Split Hopkinson Pressure Bar is an important issue for description of this material, which is commonly used in different kinds of shock absorbers. This note presents a new idea how to modify the known SHPB set up in order to investigate dynamic properties of magnetorheological materials.

Keywords:
Split Hopkinson Pressure Bar (SHPB), Magnetorheological Fluid (MRF), dynamic behaviour, solidification in magnetic field, ferroelements