Instytut Podstawowych Problemów Techniki
Polskiej Akademii Nauk

Najnowsze publikacje

Publikacje odnotowane przez trzy miesiące

1. Krajewski M., Tokarczyk M., Lewińska S., Bochenek K., Ślawska-Waniewska A., Impact of thermal oxidation on morphological, structural and magnetic properties of Fe-Ni wire-like nanochains, METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-021-06326-1, Vol.52, No.8, pp.3530-3540, 2021nota 7181

This work presents the evolution of morphological, structural and magnetic properties of amorphous Fe-Ni wire-like nanochains caused by thermal oxidation. The initial Fe1−xNix samples (x = 0.75; 0.50; 0.25) were prepared through the magnetic-field-induced synthesis, and then they were heated in dry air at 400 °C and 500 °C. These treatments led to two competing simultaneous processes occurring in the investigated samples, i.e., (i) a conversion of amorphous material into crystalline material, and (ii) their oxidation. Both of them strictly affected the morphological and structural properties of the Fe-Ni nanochains which, in turn, were associated with the amount of iron in material. It was found that the Fe0.75Ni0.25 and Fe0.50Ni0.50 nanochains were covered during thermal treatment by the nanoparticle oxides. This coverage did not constitute a good barrier against oxidation, and these samples became more oxidized than the Fe0.25Ni0.75 sample which was covered by oxide nanosheets and contained additional Ni3B phase. The specific morphological evolutions of the Fe-Ni nanochains also influenced their saturation magnetizations, whereas their coercivities did not vary significantly. The obtained results constitute an important source of information for future application of the thermally treated Fe-Ni nanochains which could be applied in the energy storage devices or catalysis.

pdf 7181(200p.)
2. Ahsani S., Claeys C., Zieliński T.G., Jankowski Ł., Scarpa F., Desmet W., Deckers E., Sound absorption enhancement in poro-elastic materials in the viscous regime using a mass–spring effect, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2021.116353, Vol.511, pp.116353-1-16, 2021nota 7193

This paper investigates the mechanisms that can be used to enhance the absorption performance of poro-elastic materials in the viscous regime. It is shown that by adding small inclusions in a poro-elastic foam layer, a mass–spring effect can be introduced. If the poro-elastic material has relatively high viscous losses in the frequency range of interest, the mass–spring effect can enhance the sound absorption of the foam by introducing an additional mode in the frame and increasing its out-of-phase movement with respect to the fluid part. Moreover, different effects such as the trapped mode effect, the modified-mode effect, and the mass–spring effect are differentiated by decomposing the absorption coefficient in terms of the three energy dissipation mechanisms (viscous, thermal, and structural losses) in poro-elastic materials. The physical and geometrical parameters that can amplify or decrease the mass–spring effect are discussed. Additionally, the influence of the incidence angle on the mass–spring effect is evaluated and a discussion on tuning the inclusion to different target frequencies is given.

Słowa kluczowe:
meta-poro-elastic material, Biot–Allard poroelastic model, mass–spring effect, viscous regime

no pdf 7193(200p.)
3. Kim H.T., Razakamandimby D.F.T., Szilagyi V., Kis Z., Szentmiklosi L., Glinicki M.A., Park K., Reconstruction of concrete microstructure using complementarity of X-ray and neutron tomography, CEMENT AND CONCRETE RESEARCH, ISSN: 0008-8846, DOI: 10.1016/j.cemconres.2021.106540, Vol.148, pp.106540-1-12, 2021nota 7216

The concrete microstructure was successfully reconstructed using the complementarity of X-ray and neutron computed tomography (CT). Neither tomogram alone was found to be suitable to properly describe the microstructure of concrete under this study. However, by merging the information revealed by the two modalities, and using image segmentation, noise reduction, and image registration techniques we reconstruct the concrete microstructure. Void, aggregate, and cement paste phases are successfully captured down to the images' spatial resolution, even though the aggregate consists of multiple minerals. The coarse-aggregate volume fraction of the reconstructed microstructure was similar to that of the mixing proportions. Furthermore, image-based finite element analysis is performed to demonstrate the effects of microstructure on stress concentration and strain localization.

Słowa kluczowe:
concrete microstructure, X-ray tomography, neutron tomography, image segmentation, complementarity field, image-based analysis

pdf 7216(200p.)
4. Golasiński K.M., Janiszewski J., Sienkiewicz J., Płociński T., Zubko M., Świec P., Pieczyska E.A., Quasi-static and dynamic compressive behavior of Gum Metal: experiment and constitutive model, METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-021-06409-z, pp.1-14, 2021nota 7232

The quasi-static and high strain rate compressive behavior of Gum Metal with composition Ti-36Nb-2Ta-3Zr-0.3O (wt pct) has been investigated using an electromechanical testing machine and a split Hopkinson pressure bar, respectively. The stress–strain curves obtained for Gum Metal tested under monotonic and dynamic loadings revealed a strain-softening effect which intensified with increasing strain rate. Moreover, the plastic flow stress was observed to increase for both static and dynamic loading conditions with increasing strain rate. The microstructural characterization of the tested Gum Metal specimens showed particular deformation mechanisms regulating the phenomena of strain hardening and strain softening, namely an adiabatic shear band formed at ~ 45 deg with respect to the loading direction as well as widely spaced deformation bands (kink bands). Dislocations within the channels intersecting with twins may cause strain hardening while recrystallized grains and kink bands with crystal rotation inside the grains may lead to strain softening. A constitutive description of the compressive behavior of Gum Metal was proposed using a modified Johnson–Cook model. Good agreement between the experimental and the numerical data obtained in the work was achieved.

pdf 7232(200p.)
5. Maj J., Węglewski W., Bochenek K., Rogal Ł., Woźniacka S., Basista M., A comparative study of mechanical properties, thermal conductivity, residual stresses, and wear resistance of aluminum-alumina composites obtained by squeeze casting and powder metallurgy, METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-021-06401-7, pp.1-10, 2021nota 7233

Squeeze casting and powder metallurgy techniques were employed to fabricate AlSi12/Al2O3 composites, which are lightweight structural materials with potential applications in the automotive industry. The impact of the processing route on the material properties was studied. Comparative analyses were conducted for the Vickers hardness, flexural strength, fracture toughness, thermal conductivity, thermal residual stresses, and frictional wear. Our results show that the squeeze cast composite exhibits superior properties to those obtained using powder metallurgy.

pdf 7233(200p.)
6. Nienałtowski K., Rigby R.E., Walczak J., Zakrzewska K.E., Głów E., Rehwinkel J., Komorowski M., Fractional response analysis reveals logarithmic cytokine responses in cellular populations, Nature Communications, ISSN: 2041-1723, DOI: 10.1038/s41467-021-24449-2, Vol.12, pp.4175-1-10, 2021nota 7257

Although we can now measure single-cell signaling responses with multivariate, high-throughput techniques our ability to interpret such measurements is still limited. Even interpretation of dose–response based on single-cell data is not straightforward: signaling responses can differ significantly between cells, encompass multiple signaling effectors, and have dynamic character. Here, we use probabilistic modeling and information-theory to introduce fractional response analysis (FRA), which quantifies changes in fractions of cells with given response levels. FRA can be universally performed for heterogeneous, multivariate, and dynamic measurements and, as we demonstrate, quantifies otherwise hidden patterns in single-cell data. In particular, we show that fractional responses to type I interferon in human peripheral blood mononuclear cells are very similar across different cell types, despite significant differences in mean or median responses and degrees of cell-to-cell heterogeneity. Further, we demonstrate that fractional responses to cytokines scale linearly with the log of the cytokine dose, which uncovers that heterogeneous cellular populations are sensitive to fold-changes in the dose, as opposed to additive changes.

pdf 7257(200p.)
7. Dulnik J., Sajkiewicz P., Crosslinking of gelatin in bicomponent electrospun fibers, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14123391, Vol.14, No.12, pp.3391-1-13, 2021nota 7176

Four chemical crosslinking methods were used in order to prevent gelatin leaching in an aqueous environment, from bicomponent polycaprolactone/gelatin (PCL/Gt) nanofibers electrospun from an alternative solvent system. A range of different concentrations and reaction times were employed to compare genipin, 1-(3-dimethylaminopropyl)-N’-ethylcarbodimide hydrochloride/N-hydroxysuccinimide (EDC/NHS), 1,4-butanediol diglycidyl ether (BDDGE), and transglutaminase. The objective was to optimize and find the most effective method in terms of reaction time and solution concentration, that at the same time provides satisfactory gelatin crosslinking degree and ensures good morphology of the fibers, even after 24 h in aqueous medium in 37 °C. The series of experiments demonstrated that, out of the four compared crosslinking methods, EDC/NHS was able to yield satisfactory results with the lowest concentrations and the shortest reaction times.

Słowa kluczowe:
crosslinking, gelatin, nanofibers, biodegradable polymers, electrospinning

no pdf 7176(140p.)
8. Steifer T., A note on the learning-theoretic characterizations of randomness and convergence, The Review of Symbolic Logic, ISSN: 1755-0203, DOI: 10.1017/S1755020321000125, pp.1-16, 2021nota 7183

Recently, a connection has been established between two branches of computability theory, namely between algorithmic randomness and algorithmic learning theory. Learning-theoretical characterizations of several notions of randomness were discovered. We study such characterizations based on the asymptotic density of positive answers. In particular, this note provides a new learning-theoretic definition of weak 2-randomness, solving the problem posed by (Zaffora Blando, Rev. Symb. Log. 2019). The note also highlights the close connection between these characterizations and the problem of convergence on random sequences.

Słowa kluczowe:
algorithmic randomness, learning theory, effectivization

no pdf 7183(140p.)
9. Kukla D., Kopeć M., Wang K., Senderowski C., Kowalewski Z.L., Nondestructive methodology for identification of local discontinuities in aluminide layer-coated Mar 247 during its fatigue performance, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14143824, Vol.14, No.14, pp.3824-1-13, 2021nota 7186

In this paper, the fatigue performance of the aluminide layer-coated and as-received MAR 247 nickel superalloy with three different initial microstructures (fine grain, coarse grain and column-structured grain) was monitored using nondestructive, eddy current methods. The aluminide layers of 20 and 40 µm were obtained through the chemical vapor deposition (CVD) process in the hydrogen protective atmosphere for 8 and 12 h at the temperature of 1040 °C and internal pressure of 150 mbar. A microstructure of MAR 247 nickel superalloy and the coating were characterized using light optical microscopy (LOM), scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS). It was found that fatigue performance was mainly driven by the initial microstructure of MAR 247 nickel superalloy and the thickness of the aluminide layer. Furthermore, the elaborated methodology allowed in situ eddy current measurements that enabled us to localize the area with potential crack initiation and its propagation during 60,000 loading cycles.

Słowa kluczowe:
chemical vapor deposition, nickel alloys, aluminide coatings, fatigue, eddy current

pdf 7186(140p.)
10. Rinoldi C., Lanzi M., Fiorelli R., Nakielski P., Zembrzycki K., Kowalewski T., Grippo V., Jezierska-Woźniak K., Maksymowicz W., Camposeo A., Bilewicz R., Pisignano D., Sanai N., Pierini F., Pierini F., Three-dimensional printable conductive semi-interpenetrating polymer network hydrogel for neural tissue applications, BIOMACROMOLECULES, ISSN: 1525-7797, DOI: 10.1021/acs.biomac.1c00524, Vol.22, No.7, pp.3084-3098, 2021nota 7189

Intrinsically conducting polymers (ICPs) are widely used to fabricate biomaterials; their application in neural tissue engineering, however, is severely limited because of their hydrophobicity and insufficient mechanical properties. For these reasons, soft conductive polymer hydrogels (CPHs) are recently developed, resulting in a water-based system with tissue-like mechanical, biological, and electrical properties. The strategy of incorporating ICPs as a conductive component into CPHs is recently explored by synthesizing the hydrogel around ICP chains, thus forming a semi-interpenetrating polymer network (semi-IPN). In this work, a novel conductive semi-IPN hydrogel is designed and synthesized. The hybrid hydrogel is based on a poly(N-isopropylacrylamide-co-N-isopropylmethacrylamide) hydrogel where polythiophene is introduced as an ICP to provide the system with good electrical properties. The fabrication of the hybrid hydrogel in an aqueous medium is made possible by modifying and synthesizing the monomers of polythiophene to ensure water solubility. The morphological, chemical, thermal, electrical, electrochemical, and mechanical properties of semi-IPNs were fully investigated. Additionally, the biological response of neural progenitor cells and mesenchymal stem cells in contact with the conductive semi-IPN was evaluated in terms of neural differentiation and proliferation. Lastly, the potential of the hydrogel solution as a 3D printing ink was evaluated through the 3D laser printing method. The presented results revealed that the proposed 3D printable conductive semi-IPN system is a good candidate as a scaffold for neural tissue applications.

no pdf 7189(140p.)
11. Poma A.B., Tran T.M.T., Lam T.M.T., Hoang N.L., Mai L.S., Nanomechanical stability of Aβ tetramers and fibril-like structures: molecular dynamics simulations, JOURNAL OF PHYSICAL CHEMISTRY B, ISSN: 1520-6106, DOI: 10.1021/acs.jpcb.1c02322, Vol.125, No.28, pp.7628-7637, 2021nota 7194

Alzheimer’s disease (AD) is a neurodegenerative disorder and one of the main causes of dementia. The disease is associated with amyloid beta (Aβ) peptide aggregation forming initial clusters and then fibril structure and plaques. Other neurodegenerative diseases such as type 2 diabetes, amyotrophic lateral sclerosis, and Parkinson’s disease follow a similar mechanism. Therefore, inhibition of Aβ aggregation is considered an effective way to prevent AD. Recent experiments have provided evidence that oligomers are more toxic agents than mature fibrils, prompting researchers to investigate various factors that may influence their properties. One of these factors is nanomechanical stability, which plays an important role in the self-assembly of Aβ and possibly other proteins. This stability is also likely to be related to cell toxicity. In this work, we compare the mechanical stability of Aβ-tetramers and fibrillar structures using a structure-based coarse-grained (CG) approach and all-atom molecular dynamics simulation. Our results support the evidence for an increase in mechanical stability during the Aβ fibrillization process, which is consistent with in vitro AFM characterization of Aβ42 oligomers. Namely, using a CG model, we showed that the Young modulus of tetramers is lower than that of fibrils and, as follows from the experiment, is about 1 GPa. Hydrogen bonds are the dominant contribution to the detachment of one chain from the Aβ fibril fragment. They tend to be more organized along the pulling direction, whereas in the Aβ tetramers no preference is observed.

pdf 7194(140p.)
12. Dias Y.J., Robles J.R., Sinha-Ray S., Abiade J., Pourdeyhimi B., Niemczyk-Soczyńska B., Kołbuk D., Sajkiewicz P., Yarin A.L., Solution-blown poly(hydroxybutyrate) and ε-poly-l-lysine submicro- and microfiber-based sustainable nonwovens with antimicrobial activity for single-use applications, ACS BIOMATERIALS SCIENCE & ENGINEERING, ISSN: 2373-9878, DOI: 10.1021/acsbiomaterials.1c00594, pp.1-13, 2021nota 7208

Antimicrobial nonwovens for single use applications (e.g., diapers, sanitary napkins, medical gauze, etc.) are of utmost importance as the first line of defense against bacterial infections. However, the utilization of petrochemical nondegradable polymers in such nonwovens creates sustainability-related issues. Here, sustainable poly(hydroxybutyrate) (PHB) and ε-poly-l-lysine (ε-PLL) submicro- and microfiber-based antimicrobial nonwovens produced by a novel industrially scalable process, solution blowing, have been proposed. In such nonwovens, ε-PLL acts as an active material. In particular, it was found that most of ε-PLL is released within the first hour of deployment, as is desirable for the applications of interest. The submicro- and microfiber mat was tested against C. albicans and E. coli, and it was found that ε-PLL-releasing microfibers result in a significant reduction of bacterial colonies. It was also found that ε-PLL-releasing antimicrobial submicro- and microfiber nonwovens are safe for human cells in fibroblast culture. Mechanical characterization of these nonwovens revealed that, even though they are felt as soft and malleable, they possess sufficient strength, which is desirable in the end-user applications.

Słowa kluczowe:
PHB submicro- and microfibers, antimicrobial nonwovens, ε-PLL release, E. coli, C. albicans

no pdf 7208(140p.)
13. Michalska M., Buchberger D.A., Jasiński J.B., Thapa A.K., Jain A., Surface modification of nanocrystalline LiMn2O4 using graphene oxide flakes, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14154134, Vol.14, No.15, pp.4134-1-13, 2021nota 7215

In this work, a facile, wet chemical synthesis was utilized to achieve a series of lithium manganese oxide (LiMn2O4, (LMO) with 1–5%wt. graphene oxide (GO) composites. The average crystallite sizes estimated by the Rietveld method of LMO/GO nanocomposites were in the range of 18–27 nm. The electrochemical performance was studied using CR2013 coin-type cell batteries prepared from pristine LMO material and LMO modified with 5%wt. GO. Synthesized materials were tested as positive electrodes for Li-ion batteries in the voltage range between 3.0 and 4.3 V at room temperature. The specific discharge capacity after 100 cycles for LMO and LMO/5%wt. GO were 84 and 83 mAh g^−1, respectively. The LMO material modified with 5%wt. of graphene oxide flakes retained more than 91% of its initial specific capacity, as compared with the 86% of pristine LMO material.

Słowa kluczowe:
lithium manganese oxide, LiMn2O4, graphene oxide, cathode material, lithium ion battery

no pdf 7215(140p.)
14. Marinelli M., Candini A., Monti F., Boschi A., Zangoli M., Salatelli E., Pierini F., Lanzi M., Zanelli A., Gazzano M., Di Maria F., Push–pull thiophene-based small molecules with donor and acceptor units of varying strength for photovoltaic application: beyond P3HT and PCBM, Journal of Materials Chemistry C, ISSN: 2050-7526, DOI: 10.1039/d1tc02641k, pp.1-13, 2021nota 7231

Here is reported an expedient synthesis implementing enabling technologies of a family of thiophene-based heptamers alternating electron donor (D) and acceptor (A) units in a D–A′–D–A–D–A′–D sequence. The nature of the peripheral A groups (benzothiadiazole vs. thienopyrrole-dione vs. thiophene-S,S-dioxide) and the strength of the donor units (alkyl vs. thioalkyl substituted thiophene ring) have been varied to finely tune the chemical-physical properties of the D–A oligomers, to affect the packing arrangement in the solid-state as well as to enhance the photovoltaic performances. The optoelectronic properties of all compounds have been studied by means of optical spectroscopy, electrochemistry, and density functional theory calculations. Electrochemical measurements and Kelvin probe force microscopy (KPFM) predicted a bifunctional behaviour for these oligomers, suggesting the possibility of using them as donor materials when blended with PCBM, and as acceptor materials when coupled with P3HT. Investigation of their photovoltaic properties confirmed this unusual characteristic, and it is shown that the performance can be tuned by the different substitution pattern. Furthermore, thanks to their ambivalent character, binary non-fullerene small-molecule organic solar cells with negligible values of HOMO and LUMO offsets were also fabricated, resulting in PCEs ranging between 2.54–3.96%.

pdf 7231(140p.)
15. Jóźwiak-Niedźwiedzka D., Gmeling K., Antolik A., Dziedzic K., Glinicki M.A., Assessment of long lived isotopes in alkali-silica resistant concrete designed for nuclear installations, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14164595, Vol.14, No.16, pp.4595-1-15, 2021nota 7247

The design of concrete for radiation shielding structures is principally based on the selection of materials of adequate elemental composition and mix proportioning to achieve the long-term durability in nuclear environment. Concrete elements may become radioactive through exposure to neutron radiation from the nuclear reactor. A selection of constituent materials of greatly reduced content of long-lived residual radioisotopes would reduce the volume of low-level waste during plant decommissioning. The objective of this investigation is an assessment of trace elements with a large activation cross section in concrete constituents and simultaneous evaluation of susceptibility of concrete to detrimental alkali-silica reaction. Two isotopes 60Co and 152Eu were chosen as the dominant long-lived residual radioisotopes and evaluated using neutron activation analysis. The influence of selected mineral aggregates on the expansion due to alkali-silica reaction was tested. The content of 60Co and 152Eu activated by neutron radiation in fine and coarse aggregates, as well as in four types of Portland cement, is presented and discussed in respect to the chemical composition and rock origin. Conflicting results were obtained for quartzite coarse aggregate and siliceous river sand that, despite a low content, 60Co and 152Eu exhibited a high susceptibility to alkali-silica reaction in Portland cement concrete. The obtained results facilitate a multicriteria selection of constituents for radiation-shielding concrete.

Słowa kluczowe:
alkali-silica reaction, concrete durability, low-level radioactive waste, neutron activation analysis, radiation shielding concrete, trace elements

pdf 7247(140p.)
16. Nosewicz S., Bazarnik P., Clozel M., Kurpaska Ł., Jenczyk P., Jarząbek D., Chmielewski M., Romelczyk-Baishya B., Lewandowska M., Pakieła Z., Huang Y., Langdon T.G., A multiscale experimental analysis of mechanical properties and deformation behavior of sintered copper–silicon carbide composites enhanced by high-pressure torsion, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1007/s43452-021-00286-4, Vol.21, pp.131-1-19, 2021nota 7259

Experiments were conducted to investigate, within the framework of a multiscale approach, the mechanical enhancement, deformation and damage behavior of copper–silicon carbide composites (Cu–SiC) fabricated by spark plasma sintering (SPS) and the combination of SPS with high-pressure torsion (HPT). The mechanical properties of the metal–matrix composites were determined at three different length scales corresponding to the macroscopic, micro- and nanoscale. Small punch testing was employed to evaluate the strength of composites at the macroscopic scale. Detailed analysis of microstructure evolution related to SPS and HPT, sample deformation and failure of fractured specimens was conducted using scanning and transmission electron microscopy. A microstructural study revealed changes in the damage behavior for samples processed by HPT and an explanation for this behavior was provided by mechanical testing performed at the micro- and nanoscale. The strength of copper samples and the metal–ceramic interface was determined by microtensile testing and the hardness of each composite component, corresponding to the metal matrix, metal–ceramic interface, and ceramic reinforcement, was measured using nano-indentation. The results confirm the advantageous effect of large plastic deformation on the mechanical properties of Cu–SiC composites and demonstrate the impact on these separate components on the deformation and damage type.

Słowa kluczowe:
copper–silicon carbide composite, high-pressure torsion, metal–matrix composites, multiscale analysis, nano-indentation, small punch test

pdf 7259(140p.)
17. Krajewski M., Tokarczyk M., Lewińska S., Brzózka K., Bochenek K., Ślawska-Waniewska A., Evolution of structural and magnetic properties of Fe-Co wire-like nanochains caused by annealing atmosphere, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14164748, Vol.14, No.16, pp.4748-1-14, 2021nota 7260

Thermal treatment is a post-synthesis treatment that aims to improve the crystallinity and interrelated physical properties of as-prepared materials. This process may also cause some unwanted changes in materials like their oxidation or contamination. In this work, we present the post-synthesis annealing treatments of the amorphous Fe1−xCox (x = 0.25; 0.50; 0.75) Wire-like nanochains performed at 400 °C in two different atmospheres, i.e., a mixture of 80% nitrogen and 20% hydrogen and argon. These processes caused significantly different changes of structural and magnetic properties of the initially-formed Fe-Co nanostructures. All of them crystallized and their cores were composed of body-centered cubic Fe-Co phase, whereas their oxide shells comprised of a mixture of CoFe2O4 and Fe3O4 phases. However, the annealing carried out in hydrogen-containing atmosphere caused a decomposition of the initial oxide shell layer, whereas a similar process in argon led to its slight thickening. Moreover, it was found that the cores of thermally-treated Fe0.25Co0.75 nanochains contained the hexagonal closest packed (hcp) Co phase and were covered by the nanosheet-like shell layer in the case of annealing performed in argon. Considering the evolution of magnetic properties induced by structural changes, it was observed that the coercivities of annealed Fe-Co nanochains increased in comparison with their non-annealed counterparts. The saturation magnetization (MS) of the Fe0.25Co0.75 nanomaterial annealed in both atmospheres was higher than that for the non-annealed sample. In turn, the MS of the Fe0.75Co0.25 and Fe0.50Co0.50 nanochains annealed in argon were lower than those recorded for non-annealed samples due to their partial oxidation during thermal processing.

Słowa kluczowe:
annealing, amorphous materials, Fe-Co nanochains, magnetic-field-induced synthesis, wire-like nanostructure

no pdf 7260(140p.)
18. Libura T., Boumbimba R.M., Rusinek A., Kowalewski Z.L., Szymczak T., Gerard P., Effect of uniaxial fatigue aging and fabric orientation on low impact velocity response of glass fibers/elium acrylic composite laminates, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14154089, Vol.14, No.15, pp.4089-1-23, 2021nota 7269

Impact resistance is one of the most critical features of composite structures, and therefore, its examination for a new material has a fundamental importance. This paper is devoted to the characterization of the fully recyclable thermoplastic ELIUM acrylic resin reinforced by glass fabric woven, which belongs to a new category of materials requiring advanced testing before their application in responsible elements of engineering structures. Its high strength, low weight as well as low production cost give excellent opportunities for its wide application in the automotive industry as a replacement of the thermoset-based laminates. The study presents an experimental work concerning the effect of damage due to low and high cyclic fatigue aging of two groups of specimens, first with the woven fabric orientations of [0°/90°]4 and secondly with [45°/45°]4, on the low impact velocity properties. The impact resistance was measured in terms of load peak, absorbed energy, penetration threshold and damage analysis. The low velocity impact results indicate that the uniaxial cyclic loading (fatigue aging) of the material leads to the reduction of impact resistance, especially at the high impact energy levels. Scanning Electron Microscopy (SEM) and Computed Tomography (CT) scan observations reveal that the damage area grows with the increase of both strain amplitude and impact energy.

Słowa kluczowe:
elium acrylic, glass fibers, composite laminates, fatigue aging, low impact velocity, damage

pdf 7269(140p.)
19. Fantilli A.P., Jóźwiak-Niedźwiedzka D., Denis P., Bio-fibres as a reinforcement of gypsum composites, Materials, ISSN: 1996-1944, DOI: 10.3390/ma14174830, Vol.14, No.17, pp.4830-1-14, 2021nota 7270

Three series of tests performed on fibre-reinforced gypsum composites are described herein. Sheep wool fibres and hemp fibres were used as reinforcement. The aim was to evaluate the capability of these biomaterials to enhance the fracture toughness of the gypsum matrix. The mechanical properties were measured by means of flexural tests on small specimens, whereas scanning electron microscopy with energy dispersive spectroscopy and X-ray diffraction were used to analyse the microstructure and composition of the fibres and of the gypsum composites. As a result, wool fibres were shown to improve the mechanical performance of the gypsum matrix, better than hemp fibres. This is due to the high adhesion at the interface of the fibre and gypsum matrix, because the latter tends to roughen the surface of the wool and, consequently to increase the bond strength. This preliminary research carried out shows that this type of biofiber—a waste material—can be considered a promising building material in sustainable and environmentally friendly engineering.

Słowa kluczowe:
organic waste material, fibre-reinforced gypsum, mechanical properties, microstructure

pdf 7270(140p.)
20. Dobruch-Sobczak K.S., Piotrzkowska-Wróblewska H., Karwat P., Klimonda Z., Markiewicz-Grodzicka E., Litniewski J., Quantitative assessment of the echogenicity of a breast tumor predicts the response to neoadjuvant chemotherapy, Cancers, ISSN: 2072-6694, DOI: 10.3390/cancers13143546, Vol.13, No.14, pp.3546-1-22, 2021nota 7273

The aim of the study was to improve monitoring the treatment response in breast cancer patients undergoing neoadjuvant chemotherapy (NAC). The IRB approved this prospective study. Ultrasound examinations were performed prior to treatment and 7 days after four consecutive NAC cycles. Residual malignant cell (RMC) measurement at surgery was the standard of reference. Alteration in B-mode ultrasound (tumor echogenicity and volume) and the Kullback-Leibler divergence (kld), as a quantitative measure of amplitude difference, were used. Correlations of these parameters with RMC were assessed and Receiver Operating Characteristic curve (ROC) analysis was performed. Thirty-nine patients (mean age 57 y.) with 50 tumors were included. There was a significant correlation between RMC and changes in quantitative parameters (KLD) after the second, third and fourth course of NAC, and alteration in echogenicity after the third and fourth course. Multivariate analysis of the echogenicity and KLD after the third NAC course revealed a sensitivity of 91%, specificity of 92%, PPV = 77%, NPV = 97%, accuracy = 91%, and AUC of 0.92 for non-responding tumors (RMC ≥ 70%). In conclusion, monitoring the echogenicity and KLD parameters made it possible to accurately predict the treatment response from the second course of NAC.

Słowa kluczowe:
quantitative ultrasound, B-mode ultrasound, echogenicity, breast cancer, neoadjuvant chemotherapy

pdf 7273(140p.)
21. Chudziński P., Parameters of Tomonaga-Luttinger liquid in a quasi-one-dimensional material with Coulomb interactions, Physical Review B, ISSN: 2469-9969, DOI: 10.1103/PhysRevB.103.155122, Vol.103, pp.155122-1-12, 2021nota 7286

We derive a scheme to calculate the Tomonaga-Luttinger liquid’s (TLL) parameters and the holon velocity in a quasi-one-dimensional (quasi-1D) material that consists of two-leg ladders coupled through Coulomb interactions. First, we obtain an analytic formula for electron-electron interaction potential along the conducting axis for a generalized charge distribution in a plane perpendicular to it. Then, we introduce many-body screening that is present in a quasi-1D material by proposing an approximation for the charge susceptibility. Based on this we are able to find the TLL’s parameters and velocities. We then show how to use these to validate the experimental angle-resolved photoemission spectroscopy data measured recently in p polarization in NbSe3. Although we focus our study on this specific material, it is applicable for any quasi-1D system that consists of two-leg ladders as its basic units.

pdf 7286(140p.)
22. Cidonio G., Costantini M., Pierini F., Scognamiglio C., Agarwal T., Barbetta A., 3D printing of biphasic inks: beyond single-scale architectural control, Journal of Materials Chemistry C, ISSN: 2050-7526, DOI: 10.1039/d1tc02117f, pp.1-20, 2021nota 7287

To date, Additive Manufacturing (AM) has come to the fore as a major disruptive technology embodying two main research lines – developing increasingly sophisticated printing technologies and new processable materials. The latter has fostered a tremendous leap in AM technological advancement, allowing 3D printing to play a central role in dictating the tailorable settings for material design. In particular, the manufacturing of three-dimensional (3D) objects with functional hierarchical porous structure is of the utmost importance for numerous research areas, including tissue engineering, catalysis, aerospace, environmental science, electrochemistry, energy and sound absorption and light engineering materials. Biphasic inks such as emulsions, foams, and solid dispersions represent viable templating systems to realise multiscale porosity. The combination of AM techniques and biphasic inks provide pivotal control over multiple levels of material structure and function, enabling the use of advanced materials with unprecedented 3D architectures as well as physical, chemical, and mechanical properties. The related potential benefits are significant, with functional perspectives for a wide variety of research fields. In this concise review, we provide an updated overview of the employment of biphase inks and show how they are adapted to different AM technologies or vice versa.

no pdf 7287(140p.)
23. Gabriele V.R., Mazhabi R.M., Alexander N., Mukherjee P., Seyfried T.N., Nwaji N., Akinoglu E.M., Mackiewicz A., Zhou G., Giersig M., Naughton M.J., Kempa K., Light- and melanin nanoparticle-induced cytotoxicity in metastatic cancer cells, Pharmaceutics, ISSN: 1999-4923, DOI: 10.3390/pharmaceutics13070965, Vol.13, No.7, pp.965-1-14, 2021nota 7177

Melanin nanoparticles are known to be biologically benign to human cells for a wide range of concentrations in a high glucose culture nutrition. Here, we show cytotoxic behavior at high nanoparticle and low glucose concentrations, as well as at low nanoparticle concentration under exposure to (nonionizing) visible radiation. To study these effects in detail, we developed highly monodispersed melanin nanoparticles (both uncoated and glucose-coated). In order to study the effect of significant cellular uptake of these nanoparticles, we employed three cancer cell lines: VM-M3, A375 (derived from melanoma), and HeLa, all known to exhibit strong macrophagic character, i.e., strong nanoparticle uptake through phagocytic ingestion. Our main observations are: (i) metastatic VM-M3 cancer cells massively ingest melanin nanoparticles (mNPs); (ii) the observed ingestion is enhanced by coating mNPs with glucose; (iii) after a certain level of mNP ingestion, the metastatic cancer cells studied here are observed to die—glucose coating appears to slow that process; (iv) cells that accumulate mNPs are much more susceptible to killing by laser illumination than cells that do not accumulate mNPs; and (v) non-metastatic VM-NM1 cancer cells also studied in this work do not ingest the mNPs, and remain unaffected after receiving identical optical energy levels and doses. Results of this study could lead to the development of a therapy for control of metastatic stages of cancer.

Słowa kluczowe:
melanoma, melanin nanoparticles, cytotoxicity, laser medical applications, hyperthermia

pdf 7177(100p.)
24. Gambin B., Kruglenko E., Ultrasonic specific absorption rate in nanoparticle-mediated moderate hyperthermia, BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 2300-1917, DOI: 10.24425/bpasts.2021.137053, Vol.69, No.3, pp.e137053-1-18, 2021nota 7178

Magnetic nanoparticle’s different applications in nanomedicine, due to their unique physical properties and biocompatibility, were intensively investigated. Recently, Fe3O4 nanoparticles, are confirmed to be the best sonosensitizers to enhance the performance of HIFU (high intensity focused ultrasound). They are also used as thermo-sensitizers in magnetic hyperthermia. A new idea of dual, magneto-ultrasound, coupled hyperthermia allows the ultrasound intensity to be reduced from the high to a moderate level. Our goal is to evaluate the enhancement of thermal effects of focused ultrasound of moderate intensity due to the presence of nanoparticles. We combine experimental results with numerical analysis. Experiments are performed on tissue-mimicking materials made of the 5% agar gel and gel samples containing Fe3O4 nanoparticles with φ = 100 nm with two fractions of 0.76 and 1.53% w/w. Thermocouples registered curves of temperature rising during heating by focused ultrasound transducer with acoustic powers of the range from 1 to 4 W. The theoretical model of ultrasound-thermal coupling is solved in COMSOL Multiphysics. We compared the changes between the specific absorption rates (SAR) coefficients determined from the experimental and numerical temperature rise curves depending on the nanoparticle fractions and applied acoustic powers.We confirmed that the significant role of nanoparticles in enhancing the thermal effect is qualitatively similarly estimated, based on experimental and numerical results. So that we demonstrated the usefulness of the FEM linear acoustic model in the planning of efficiency of nanoparticle-mediated moderate hyperthermia.

Słowa kluczowe:
ultrasonic hyperthermia, agar-based tissue mimicking phantom, magnetic nanoparticles, temperature, specific absorption rate (SAR)

pdf 7178(100p.)
25. Postek E., Nowak Z., Pęcherski R.B., Viscoplastic flow of functional cellular materials with use of peridynamics, MECCANICA, ISSN: 0025-6455, DOI: 10.1007/s11012-021-01383-7, pp.1-18, 2021nota 7182

The subject of the study is the deformation of the oxygen-free high conductivity copper. The copper sample is given in the form of a foam. The sample undergoes an impact into an elastic wall. The strain rate hardening effect is investigated. The numerical model of the open-cell foam skeleton is prepared in the framework of the peridynamics method. The dynamic process of compression with different impact velocities is simulated. It has been found that the strain rate hardening effect is essential for the load-carrying capacity of the material under study. Taylor impact test of solid cylinder analysis precedes the analysis of the metallic foam.

Słowa kluczowe:
cellular materials, OFHC copper, elastic-viscoplastic model, strain rate hardening, peridynamics, foam skeleton

pdf 7182(100p.)
26. Badora M., Sepe M., Bielecki M., Graziano A., Szolc T., Predicting length of fatigue cracks by means of machine learningalgorithms in the small-data regime, EKSPLOATACJA I NIEZAWODNOŚĆ - MAINTENANCE AND RELIABILITY, ISSN: 1507-2711, DOI: 10.17531/ein.2021.3.19, Vol.23, No.3, pp.575-585, 2021nota 7188

In this paper several statistical learning algorithms are used to predict the maximal length of fatigue cracks based on a sample composed of 31 observations. The small-data regime is still a problem for many professionals, especially in the areas where failures occur rarely. The analyzed object is a high-pressure Nozzle of a heavy-duty gas turbine. Operating parameters of the engines are used for the regression analysis. The following algorithms are used in this work: multiple linear and polynomial regression, random forest, kernel-based methods, AdaBoost and extreme gradient boosting and artificial neural networks. A substantial part of the paper provides advice on the effective selection of features. The paper explains how to process the dataset in order to reduce uncertainty; thus, simplifying the analysis of the results. The proposed loss and cost functions are custom and promote solutions accurately predicting the longest cracks. The obtained results confirm that some of the algorithms can accurately predict maximal lengths of the fatigue cracks, even if the sample is small.

Słowa kluczowe:
empirical models, fatigue cracks, predictive maintenance, regression analysis, small data, statistical learning, turbomachinery

no pdf 7188(100p.)
27. Piechocka I.K., Keary S., Sosa-Costa A., Lau L., Mohan N., Stanisavljevic J., Borgman K.J.E., Lakadamyali M., Manzo C., Garcia-Parajo M.F., Shear forces induce ICAM-1 nanoclustering on endothelial cells that impact on T-cell migration, BIOPHYSICAL JOURNAL, ISSN: 0006-3495, DOI: 10.1016/j.bpj.2021.05.016, Vol.120, No.13, pp.2644-2656, 2021nota 7190

The leukocyte-specific β2-integrin LFA-1 and its ligand ICAM-1, expressed on endothelial cells (ECs), are involved in the arrest, adhesion, and transendothelial migration of leukocytes. Although the role of mechanical forces on LFA-1 activation is well established, the impact of forces on its major ligand ICAM-1 has received less attention. Using a parallel-plate flow chamber combined with confocal and super-resolution microscopy, we show that prolonged shear flow induces global translocation of ICAM-1 on ECs upstream of flow direction. Interestingly, shear forces caused actin rearrangements and promoted actin-dependent ICAM-1 nanoclustering before LFA-1 engagement. T cells adhered to mechanically prestimulated ECs or nanoclustered ICAM-1 substrates developed a promigratory phenotype, migrated faster, and exhibited shorter-lived interactions with ECs than when adhered to non mechanically stimulated ECs or to monomeric ICAM-1 substrates. Together, our results indicate that shear forces increase ICAM-1/LFA-1 bonds because of ICAM-1 nanoclustering, strengthening adhesion and allowing cells to exert higher traction forces required for faster migration. Our data also underscore the importance of mechanical forces regulating the nanoscale organization of membrane receptors and their contribution to cell adhesion regulation.

no pdf 7190(100p.)
28. Rinoldi C., Zargarian S.S., Nakielski P., Li X., Liguori A., Petronella F., Presutti D., Wang Q., Costantini M., De Sio L., Gualandi C., Ding B., Pierini F., Nanotechnology-assisted RNA delivery: from nucleic acid therapeutics to COVID-19 vaccines, Small Methods, ISSN: 2366-9608, DOI: 10.1002/smtd.202100402, pp.2100402-1-49, 2021nota 7195

In recent years, the main quest of science has been the pioneering of the groundbreaking biomedical strategies needed for achieving a personalized medicine. Ribonucleic acids (RNAs) are outstanding bioactive macromolecules identified as pivotal actors in regulating a wide range of biochemical pathways. The ability to intimately control the cell fate and tissue activities makes RNA-based drugs the most fascinating family of bioactive agents. However, achieving a widespread application of RNA therapeutics in humans is still a challenging feat, due to both the instability of naked RNA and the presence of biological barriers aimed at hindering the entrance of RNA into cells. Recently, material scientists’ enormous efforts have led to the development of various classes of nanostructured carriers customized to overcome these limitations. This work systematically reviews the current advances in developing the next generation of drugs based on nanotechnology-assisted RNA delivery. The features of the most used RNA molecules are presented, together with the development strategies and properties of nanostructured vehicles. Also provided is an in-depth overview of various therapeutic applications of the presented systems, including coronavirus disease vaccines and the newest trends in the field. Lastly, emerging challenges and future perspectives for nanotechnology-mediated RNA therapies are discussed.

no pdf 7195(100p.)
29. Białas M., Maciejewski J., Kucharski S., Friction coefficient of solid lubricating coating as a function of contact pressure: experimental results and microscale modeling, CONTINUUM MECHANICS AND THERMODYNAMICS, ISSN: 0935-1175, DOI: 10.1007/s00161-021-00999-0, Vol.33, pp.1733-1745, 2021nota 7271

The paper presents experimental analysis of relation between friction coefficient and contact pressure of MoS2 film deposited on Ti6Al4V substrate in contact with sapphire ball during reciprocating sliding motion. It is shown that the value of friction coefficient decreases with increasing contact pressure. A microscale modeling approach is next developed to mimic the experimental observations. Representative volume element is defined based on the actual topography of outer surface of MoS2 film. Assuming thermo-elastic material properties, the calculations on the asperity level are performed in two steps. Firstly, the mechanical contact between two surfaces is calculated. As a result, the relation between the global load and micro-stress distribution is obtained. Secondly, for a given stress load, thermal analysis is performed providing temperature fluctuation within simplified conical asperity. By assuming relation between friction coefficient and temperature on the microscale, it is possible to obtain macroscopic friction coefficient as a function of contact pressure. In the end, model results are compared with experimental data. The novel aspects of presented approach lie in the selection of three main factors on a micro-level defining macroscopic friction. They are actual surface topography, microscopic temperature and microscopic friction-temperature relation.

Słowa kluczowe:
microscale modeling, friction coefficient, flash temperature, reciprocating motion test

pdf 7271(100p.)
30. Fura Ł., Dera W., Dziekoński C., Świątkiewicz M., Kujawska T., Experimental evaluation of targeting accuracy of ultrasound imaging-guided robotic HIFU ablative system for the treatment of solid tumors in pre-clinical studies, APPLIED ACOUSTICS, ISSN: 0003-682X, DOI: 10.1016/j.apacoust.2021.108367, Vol.184, pp.108367-1-9, 2021nota 7274

We have designed and built low-cost compact ultrasound imaging-guided robotic HIFU (High-Intensity Focused Ultrasound) ablation device for thermal damage of solid tumors in small animals. Before this device is used to treat animals, experimental studies on ex vivo tissues were necessary to assess the accuracy of its targeting, ensuring the safety of therapy. The objective of this study was to assess the targeting accuracy of our device in the focal and axial plane of the HIFU beam using ex vivo tissue embedded in a reference cylindrical chamber inside which a coaxial cylindrical volume with a smaller diameter was ablated. HIFU beams with selected acoustic parameters, generated by a singe-element bowl-shaped 64-mm HIFU transducer operating at 1.08 MHz or 3.21 MHz frequency, were propagated in two-layer media: water-tissue (50 mm-40 mm) and focused at 12.6-mm depth below the tissue surface. Cylindrical necrotic lesions of various size were created by moving the chamber using a computercontrolled precise positioning unit. Lesions formed were compared with those intended for treatment using various visualization methods and displacement between their centers were determined. The targeting accuracy in the focal and axial planes was found to be respectively about 98% and 86% when determined from photos and about 88% and 76% when determined from MR images. The displacement between the centers of the necrotic lesion formed and planned for treatment was about 1 mm in the focal plane and about 2 mm in the axial plane. Our ablation device can be used as an effective and safe tool to plan, monitor and treat solid tumors in small animals and to test new anti-cancer drugs in preclinical studies.

pdf 7274(100p.)
31. Szmidt T., Konowrocki R., Pisarski D., Stabilization of a cantilever pipe conveying fluid using electromagnetic actuators of the transformer type, MECCANICA, ISSN: 0025-6455, DOI: 10.1007/s11012-021-01419-y, pp.1-14, 2021nota 7281

The article presents an investigation of the stabilization of a cantilever pipe discharging fluid using electromagnetic actuators of the transformer type. With the flow velocity reaching a critical value, the straight equilibrium position of the pipe becomes unstable, and self-excited lateral vibrations arise. Supplying voltage to the actuators yields two opposite effects. First, each of the actuators attracts the pipe, thus introduces the effect of negative stiffness which destabilizes the middle equilibrium. Second, lateral vibrations change the gap in magnetic circuits of the actuators, which leads to oscillations of magnetic field in the cores and the electromagnetic phenomena of induction and hysteresis that impede the motion of the pipe. The combination of these two non-linear effects is ambiguous, so the problem is explored both theoretically and experimentally. First, a mathematical model of the system in form of a partial differential equation governing the dynamics of the pipe coupled with two ordinary differential equations of electro-magnetodynamics of the actuators is presented. Then, the equation of the pipe’s dynamics is discretized using the Galerkin procedure, and the resultant set of ordinary equations is solved numerically. It has been shown that the overall effect of actuators action is positive: the critical flow velocity has been increased and the amplitude of post-critical vibrations reduced. These results have been validated experimentally on a test stand.

Słowa kluczowe:
fluid-structure interaction, pipe, flow, dynamic stability, electromagnetic actuator

pdf 7281(100p.)
32. Bartkowski P., Suwała G., Zalewski R., Temperature and strain rate effects of jammed granular systems: experiments and modelling, GRANULAR MATTER, ISSN: 1434-5021, DOI: 10.1007/s10035-021-01138-x, Vol.23, pp.79-1-12, 2021nota 7288

Jammed granular systems, also known as vacuum packed particles (VPP), have begun to compete with the well commercialized group of smart structures already widely applied in various fields of industry, mainly in civil and mechanical engineering. However, the engineering applications of VPP are far ahead of the mathematical description of the complex mechanical mechanisms observed in these unconventional structures. As their wider commercialization is hindered by this gap, in the paper the authors consider experimental investigations of granular systems, mainly focusing on the mechanical responses that take place under various temperature and strain rate conditions. To capture the nonlinear behavior of jammed granular systems, a constitutive model constituting an extension of the Johnson–Cook model was developed and is presented. green The extended and modified constitutive model for VPP proposed in the paper could be implemented in the future into a commercial Finite Element Analysis code, making it possible to carry out fast and reliable numerical simulations.

Słowa kluczowe:
vacuum packed particles, granular jamming, smart materials, Johnson-Cook model

no pdf 7288(100p.)
33. Trombley C.I., Ekiel-Jeżewska M.L., Relative trajectories of two charged sedimenting particles in a Stokes flow, Journal of Physics Communications, ISSN: 2399-6528, DOI: 10.1088/2399-6528/ac060c, Vol.5, No.7, pp.075005-1-19, 2021nota 7280

We study the dynamics of two charged point particles settling in a Stokes flow. We find what ranges of initial relative positions and what ranges of system parameters lead to formation of stable doublets. The system is parameterized by the ratio of radii, ratio of masses and the ratio of electrostatic to gravitational force. We focus on opposite charges. We find a new class of stationary states with the line of the particle centers inclined with respect to gravity and demonstrate that they are always locallyasymptotically stable. Stability properties of stationary states with the vertical line of the particle centers are also discussed. We find examples of systems with multiple stable stationary states. We show that the basin of attraction for each stable stationary state has infinite measure, so that particles can capture one another even when they are very distant, and even if their charge is very small. This behavior is qualitatively different from the uncharged case where there only exists a bounded set of periodic relative trajectories. We determine the range of ratios of Stokes velocities and ratio masses which give rise to non-overlapping stable stationary states (given the appropriate ratio of electrostatic to gravitational force). For non-overlapping stable inclined or vertical stationary states the larger particle is always above the smaller particle. The non-overlapping stable inclined stationary states existonly if the larger particle has greater Stokes velocity, but there are non-overlapping stable vertical stationary states where the larger particle has higher or lower Stokes velocity.

Słowa kluczowe:
charged particles, stability, capturing orbits, Stokes equations, point-particle model

pdf 7280(70p.)
34. Kopeć M., Jóźwiak S., Kowalewski Z.L., Fe-Al based composite reinforced with ultra-fine Al2O3 oxides for high temperature applications, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl/138322, Vol.59, No.3, pp.509-513, 2021nota 7196

In this paper, an Fe-Al based composite reinforced with ultra-fine Al2O3 oxides was obtained through sintering of aluminium, iron and mullite ceramic powders using self-propagated high temperature synthesis (SHS). The powder mixture with a 50%wt. content of the ceramic reinforcement was cold pressed and subsequently subjected to the sintering process in vacuum at 1200◦C for 25 minutes under external loading of 25 kN. The complex microstructure of the Fe-Al matrix reinforced with ultra-fine Al2O3 oxides was found to be desired in high temperature applications since only 3% of the relative weight gain was observed after 100 hours of annealing at 900◦C.

Słowa kluczowe:
cermet composites, reaction synthesis, powder methods, electron microscopy

pdf 7196(40p.)
35. Morbidi F., Pisarski D., Practical and accurate generation of energy-optimal trajectories for a planar quadrotor, ICRA 202, 2021 IEEE International Conference on Robotics and Automation, 2021-05-30/06-05, Xi'an (CN), pp.1-7, 2021nota 7192

Motivated by the limited flight time of battery-powered multi-rotor UAVs, in this paper we address the problem of generating energy-optimal trajectories for a planar quadrotor. More specifically, by considering an accurate electrical model for the brushless DC motors and rest-to-rest maneuvers between two predefined boundary states, we explicitly compute the minimum-energy curves by adopting a free and a fixed end-time optimal control formulation. The numerical solution of these optimal control problems hinges upon a simple yet effective indirect projected gradient method. Simulation experiments illustrate the theory in a variety of realistic flight scenarios.

pdf 7192
36. Topolewski P., Komorowski M., Information-theoretic analyses of cellular strategies for achieving high signaling capacity—dynamics, cross-wiring, and heterogeneity of cellular states, Current Opinion in Systems Biology, ISSN: 2452-3100, DOI: 10.1016/j.coisb.2021.06.003, Vol.27, pp.100352-1-9, 2021nota 7256

An individual eukaryotic cell senses identity and quantity of ligands through molecular receptors and signaling pathways, dynamically activating signaling effectors. A distinct ligand often activates multiple different effectors, and a distinct effector is activated by numerous different ligands, which results in cross-wired signaling. In apparently identical cells, the activity of signaling effectors can vary considerably, raising questions about the accuracy of cellular signaling and the interpretation of heterogeneous responses, as either functional or simply noise. Cell-to-cell variability of signaling outcomes, signaling dynamics, and cross-wiring all give rise to signaling complexity, complicating the analysis of signaling mechanisms. Here, we consider a simple input–output modeling approach of information theory that is suitable to analyze signaling complexity and highlight recent studies that have advanced our understanding of the role different components of signaling complexity play in achieving effective information transfer along cellular signaling pathways.

Słowa kluczowe:
signaling pathways, hormones, growth factors or cytokines, signaling dynamics, cross-wired signaling, Shannon information, Fisher information

pdf 7256(20p.)
37. Kopeć M., Dubey V.P., Brodecki A., Kowalewski Z.L., Failure analysis of orthopedic implants, IMPLANTY'2021, III Ogólnopolska Konferencja Naukowa IMPLANTY2021 Koncepcja a realia we współczesnych rozwiązaniach, 2021-06-18/06-18, Gdańsk (PL), pp.1, 2021nota 7173

Słowa kluczowe:
medical fixation devices, orthopedicimplants, SEM, fracture analysis, titanium alloy, stainless steel

pdf 7173
38. Fantilli A.P., Jóźwiak-Niedźwiedzka D., Sheep wool as fiber-reinforcement of gypsum composites, ICBBM'2021, 4th International Conference on Bio-Based Building Materials, 2021-06-16/06-18, Barcelona (ES), pp.108-111, 2021nota 7175

Depending on the intended use, some cement-based construction materials, such as paste, mortar and concrete, need to be fibre reinforced. In these materials, fibres play the same mechanical role as ossein, the elastic collagen fibres in animal bones that guarantees the resistance to fracture. Although commonly used fibres are made of various materials, such as steel, glass, polymers etc., animal and plant fibres can also be used in building materials. Among them, wool of sheep, a waste material in several countries, can effectively reinforce pastes, mortars and concretes. In addition to the research already performed in the field of cement-based composites, the use of sheep wool as reinforcement of gypsum-based composite is experimentally investigated herein for the first time. As a result, sheep wool reinforcement provides high fracture toughness, due to an excellent adhesion, and could be a valid alternative to the current industrial fibres in reinforced gypsum manufacts.

Słowa kluczowe:
sheep wool fibres, gypsum-based composite, mechanical properties, microstructure

pdf 7175
39. Gambin B., Kruglenko E., Melnikova P., Tymkiewicz R., Strzałkowski R., Krajewski M., Impact of the ferrogel fine structure on magnetic heating efficiency, PM'21, The European Conference Physics of Magnetism 2021, 2021-06-28/07-02, Poznań (PL), pp.1, 2021pdf 7179
40. Gambin B., Miklewska A., Kruglenko E., Comparison of the influence of superparamagnetic nanoparticles concentration and coverage on the alternating magnetic field thermal effect, PM'21, The European Conference Physics of Magnetism 2021, 2021-06-28/07-02, Poznań (PL), pp.1, 2021pdf 7180
41. Sadowski T., Postek E., Pietras D., Boniecki M., Szutkowska M., Description of quasi-static and dynamic damage processes in 2-phase ceramic matrix and metal matrix composites reinforced by ceramic grains, ACE-X 2021, 14th INTERNATIONAL CONFERENCE ON ADVANCED COMPUTATIONAL ENGINEERING AND EXPERIMENTING - ACE-X 2021, 2021-07-04/07-08, St. Julian's (MT), pp.9-10, 2021nota 7184

Quasi-static degradation of brittle composites exhibits different mechanical responses under uniaxial tension and uniaxial compression. In this paper, we analysed cracking processes and failure under quasi-static loading of 2 phase ceramic material made of alumina and zirconia mixture, subjected to tension and compression. Constitutive modelling of two-phase ceramic composites obeys description of (1) elastic deformations of initially porous material, (2) limited plasticity and (3) cracks initiation and propagation. Modelling of polycrystalline ceramics at the mesoscopic level under mechanical loading is related to the analysis of a set of grains, which create a so-called Representative Volume Element (RVE). The basic elements of the defect structure inside polycrystal are: micro- and meso-cracks, kinked and wing cracks. To get the macroscopic response of the material one can calculate averaged values of stress and strain over the RSE with the application of an analytical approach. The dynamic degradation process was illustrated for 2 phase ceramic matrix composite and cermet, which was subjected to short compressive impulse. The pulse duration was 10-7s and the applied pressure level - 480 MPa. In the proposed, more advanced finite element formulation of the cermet behaviour is was necessary to take into account the following data and phenomena revealing inside of the RVE: (1) spatial distribution of the cermet constituents, (2) system of grain boundaries/binder interfaces modelled by interface elements, (3) rotation of brittle grains. The cermet response due to pulse loading is significantly different in comparison to the quasi-static behaviour, i.e. the stress distributions and microcracking processes are quite different.

Słowa kluczowe:
cermets, dynamic behaviour, brittle cracking

pdf 7184
42. Steifer T., Simple betting and stochasticity, CiE 2021, Connecting with Computability, 2021-07-05/07-09, Ghent (BE), DOI: 10.1007/978-3-030-80049-9_42, No.12813, pp.424-433, 2021nota 7185

A sequence of zeros and ones is called Church stochastic if all subsequences chosen in an effective manner satisfy the law of large numbers with respect to the uniform measure. This notion may be independently defined by means of simple martingales, i.e., martingales with restricted (constant) wagers (hence, simply random sequences). This paper is concerned with generalization of Church stochasticity for arbitrary (possibly non-stationary) measures. We compare two ways of doing this: (i) via a natural extension of the law of large numbers (for non-i.i.d. processes) and (ii) via restricted martingales, i.e., by redefining simple randomness for arbitrary measures. It is shown that in the general case of non-uniform measures the respective notions of stochasticity do not coincide but the first one is contained in the second.

no pdf 7185
43. Guglielmelli A., Pierini F., Tabiryan N., Umeton C., Bunning T.J., De Sio L., Thermoplasmonics with gold nanoparticles: a new weapon in modern optics and biomedicine, Advanced Photonics Research, ISSN: 2699-9293, DOI: 10.1002/adpr.202000198, Vol.2, No.8, pp.2000198-1-17, 2021nota 7191

Thermoplasmonics deals with the generation and manipulation of nanoscale heating associated with noble metallic nanoparticles. To this end, gold nanoparticles (AuNPs) are unique nanomaterials with the intrinsic capability to generate a nanoscale confined light-triggered thermal effect. This phenomenon is produced under the excitation of a suitable light of a wavelength that matches the localized surface plasmonic resonance frequency of AuNPs. Liquid crystals (LCs) and hydrogels are temperature-sensitive materials that can detect the host AuNPs and their photo-induced temperature variations. In this perspective, new insight into thermoplasmonics, by describing a series of methodologies for monitoring, detecting, and exploiting the photothermal properties of AuNPs, is offered. From conventional infrared thermography to highly sophisticated temperature-sensitive materials such as LCs and hydrogels, a new scenario in thermoplasmonic-based, next generation, photonic components is presented and discussed. Moreover, a new road in thermoplasmonic-driven biomedical applications, by describing compelling and innovative health technologies such as on-demand drug-release and smart face masks with smart nano-assisted destruction of pathogens, is proposed. The latter represents a new weapon in the fight against COVID-19.Thermoplasmonics deals with the generation and manipulation of nanoscale heating associated with noble metallic nanoparticles. To this end, gold nanoparticles (AuNPs) are unique nanomaterials with the intrinsic capability to generate a nanoscale confined light-triggered thermal effect. This phenomenon is produced under the excitation of a suitable light of a wavelength that matches the localized surface plasmonic resonance frequency of AuNPs. Liquid crystals (LCs) and hydrogels are temperature-sensitive materials that can detect the host AuNPs and their photo-induced temperature variations. In this perspective, new insight into thermoplasmonics, by describing a series of methodologies for monitoring, detecting, and exploiting the photothermal properties of AuNPs, is offered. From conventional infrared thermography to highly sophisticated temperature-sensitive materials such as LCs and hydrogels, a new scenario in thermoplasmonic-based, next generation, photonic components is presented and discussed. Moreover, a new road in thermoplasmonic-driven biomedical applications, by describing compelling and innovative health technologies such as on-demand drug-release and smart face masks with smart nano-assisted destruction of pathogens, is proposed. The latter represents a new weapon in the fight against COVID-19.

pdf 7191
44. Barwińska I., Durejko T., Kopeć M., Kowalewski Z.L., Effectiveness of LENS technology for Inconel 625 based parts repair process, Ogólnopolska Konferencja Naukowa: Druga, letnia szkoła naukowa on-line, 2021-08-07/08-07, on-line (PL), pp.1-1, 2021nota 7222

Słowa kluczowe:
LENS, additive manufacturing, Inconel 625, repair process

pdf 7222
45. Antolik A., Jóźwiak-Niedźwiedzka D., Diederichs U., Microstructural evaluation of the real concrete pavements with potential alkali aggregate reaction signs, ICAAR, 16th International Conference on Alkali-Aggregate Reaction in Concrete, 2021-01-31/06-02, Lizbona (PT), pp.1083-1092, 2021nota 7261

The paper presents results of the microstructural analysis of the expressway pavements concrete exhibiting signs of potential alkali-silica reaction (ASR). The analysis was performed on cores drilled from pavements from the northern part of Germany. Specimens were selected from regions of the pavements representing the highest degree of distress. The results obtained during microstructural characterization performed in the laboratory are presented and discussed. The microstructure of concretes was investigated using microscopy in both transmitted and reflected light as well as in scanning electron microscope (SEM) operated in the backscattered (BSE). The chemical compositions of the phases of interest were determined using the Energy Dispersive X-ray analysis (EDS). The thin sections were analyzed using petrographic microscope (under plane, crosspolarized light and with gypsum plate). The petrographic analysis of aggregates was conducted to determine the presence of potentially reactive minerals. During the microstructural analysis particular emphasis was placed on establishing exactly the type of the reaction and the distribution and the composition of the resulting gel. In addition, the Damage Rating Index method has been used to ascertain the degree of concrete pavement damage caused by ASR. During the microstructural analysis particular emphasis was placed on establishing exactly the type of the reaction and the distribution and the composition of the resulting gel. The results of the analysis revealed the presence of the deleterious reactions in pavements. Concrete showed evidence of the ASR. The reactive components were identified as schist and sandstone in the coarse aggregate and reactive siliceous fine aggregate. The resulting gel was predominantly of Si-Ca-K-Na composition.

Słowa kluczowe:
aggregate, alkali-silica reaction (ASR), gel, petrographic analysis, reactive minerals, SEM analysis

no pdf 7261
46. Glinicki M.A., Jóźwiak-Niedźwiedzka D., Antolik A., Dziedzic K., Bogusz K., Application of RILEM test methods for alkali-silica reactivity evaluation of Polish aggregates for concrete road structures, ICAAR, 16th International Conference on Alkali-Aggregate Reaction in Concrete, 2021-01-31/06-02, Lizbona (PT), pp.761-773, 2021nota 7262

Results of experimental investigations on the reactivity of crushed aggregates produced from sedimentary and igneous rocks are presented. Applied test methods, consistent with RILEM and ASTM standards are implemented in technical specifications of Polish national highway administration. The range of the investigations covered coarse aggregates produced from crushed limestone, dolomite, sandstone and greywacke rocks, as well as from basalt, melaphyre, porphyry, granite and gabbro. The aggregates were selected on the basis of their mechanical and physical properties to be adequate for making durable concrete for highway applications. The mineral composition of the aggregates was evaluated with regard to their reactive SiO2 content. A considerable amount of reactive minerals: chalcedony, tridymite and microcrystalline quartz were found in the grains of the porphyry and melaphyre aggregates. No reactive forms of quartz were found to be present in the mineralogical composition of the limestone aggregates and the dolomite aggregates. Micro- and cryptocrystalline quartz occurred in the particles of the greywacke aggregates and the sandstone aggregates. On the basis of the expansion of mortar and concrete of specimens, the coarse aggregates produced from crushed rocks were classified into three reactivity categories. A sodium-potassium-calcium silicate gel was found and its composition was consistent with that reported in the literature as characteristic of the alkali-aggregate reaction products. The tests revealed consistent assessment of the reactivity of the aggregates.

Słowa kluczowe:
alkali silica gel, expansion tests, microcrystalline quartz, petrographic analysis, technical specifications

no pdf 7262
47. Postek E., Nowak Z., Pęcherski R., Viscoplastic material with shear bands effect, USNCCM16, 16th U.S. National Congress on Computational Mechanics, 2021-07-25/07-29, Chicago (US), pp.1, 2021nota 7263

The paper‘s subject is the formulation accounting for shear bands in fine-grained metals [2] in terms of peridynamics. The formulation stands for an extension of the viscoplasticity model [1]. Several experimental investigations prove that plastic deformation's main mechanism is developing shear bands in prevailing cases. An influence of the rapid shear banding generation on the cumulated plastic strain field is investigated. The model is valid for finite strains. The primary interest is focused on impact analysis. The numerical models of the Taylor bar are shown. A complex structure, such as copper open-cell foam, were presented in [3]. The numerical examples given in [3] are enriched with the newly developed formulation.

Słowa kluczowe:
viscoplasticity, shear bands, peridynamics

pdf 7263
48. Zaszczyńska A., Sajkiewicz P., Gradys A., Smart piezoelectric scaffold for nerve regeneration, AMC, European Advanced Materials Congress, 2021-08-23/08-25, Stockholm (SE), pp.162-163, 2021nota 7264

Słowa kluczowe:
Piezo-nerve, scaffold, nanofibers, tissue engineering, stem cells

pdf 7264
49. Sadowski T., Postek E., Pietras D., Gieleta R., Kruszka L., Non-linear dynamic and quasi-static responses of two-phase ceramic matrix and metal matrix composites subjected to compression and degradation, ICTAM2021, 25th International Congress of Theoretical and Applied Mechanics, 2021-08-22/08-27, Mediolan (virtual) (IT), pp.257-258, 2021nota 7265

The paper presents modelling and experimental testing of non-linear degradation processes developing in the two-phase ceramic matrix (CMCs) and metal matrix composites (MMCs) subjected to quasi-static and dynamic compressive loading. Modelling was performed by a multiscale approach using both: (1) analytical and (2) numerical methods and selected Representative Volume Elements (RVE) based on SEM observations of composites. Both quasi-static and dynamic experimental tests were done applying standard MTS (100 kN) servo-hydraulic machine and Split Hopkinson Pressure Bar (SHPB) stand for impact tests with loading velocities 20 – 30 m/s. As a result, we observed for CMCs in quasi-static loading failure mode by splitting of cylindrical samples, whereas for impact loading dynamic crushing process took place.

Słowa kluczowe:
metal-matrix composites, dynamic testing, Split Hopkinson Pressure Bar, peridynamics

pdf 7265
50. Postek E., Sadowski T., Bieniaś J., Boniecki M., Dynamic impact of a ceramic skeleton of interpenetrating phase composites, ICTAM2021, 25th International Congress of Theoretical and Applied Mechanics, 2021-08-22/08-27, Mediolan (virtual) (IT), pp.308-309, 2021nota 7266

The paper presents the modelling of a ceramic foam that works as a skeleton of Interpenetrating Phase Composites (IPCs) before filling the preforms. The preforms are made of SiC or Al2O3. A dynamic analysis of the impact of such skeletons against the rigid surface is performed. The results of the quasi-static analysis will serve as a reference to the dynamic analyses. The analysis of the IPCs skeleton is performed due to evaluation of the role of the skeleton in a final product that is the filled IPCs.

Słowa kluczowe:
interpenetrating phase composites, metal-matrix composites, ceramic skeleton, peridynamics, high-performance computing

pdf 7266
51. Niemczyk-Soczyńska B., Dulnik J., Jeznach O., Sajkiewicz P., Fragmentation of bioactive electrospun PLLA fibers, AMC, European Advanced Materials Congress, 2021-08-23/08-25, Stockholm (SE), pp.164-165, 2021nota 7267

Słowa kluczowe:
electrospinning, ultrasonication, short fibers, polymers, scaffold

pdf 7267
52. Szymczak T., Brodecki A., Sobolewski T., Laboratoryjna ocena stanu technicznego komponentów do pojazdów samochodowych, Przegląd Techniczny, ISSN: 0137-8783, Vol.7, pp.16-18, 2021nota 7268

W pracy zamieszczono szczegóły prowadzenia badań stanowiskowych wybranych podzespołów do pojazdów samochodowych. Zaprezentowano niezbędne komponenty stanowiska badawczego do prowadzenia wymienionych rodzajów testów, jak: platformę badawczą, siłownik, systemy mocowania, urządzenie DIC PONTOS 5M - przeznaczone do bezkontaktowych pomiarów parametrów kinematycznych obiektów badań. Omówiono rezultaty prób stanowiskowych, pochodzące z testów zaczepów kulowych oraz Tylnego Urządzenia Zabezpieczającego (TUZ), przedstawiając zmiany składowych ugięcia. Zamieszczono wybrane przypadki pęknięć komponentów różnego typu i wykonanych z różnych materiałów konstrukcyjnych, zawierając spoiny oraz strefy do nich przynależne.

no pdf 7268
53. Ustrzycka A., Nowak M., Microdamage and fracture initiation in the materials subjected to ion-irradiation, ICTAM2021, 25th International Congress of Theoretical and Applied Mechanics, 2021-08-22/08-27, Mediolan (virtual) (IT), pp.1685-1686, 2021pdf 7272
54. Kopeć M., Yuan X., Wang K., Wang L., Kowalewski Z.L., Microstructure and damage evolution of Ti6Al4V under fast forming conditions, BSSM, 15th International Conference on Advances in Experimental Mechanics, 2021-09-07/09-09, Swansea (GB), pp.1-2, 2021nota 7275

The paper aims to investigate the nature of fracture behaviour through the microstructural and damage evolution analysis of a titanium alloy (Ti6Al4V) with tailored initial microstructures under FAST conditions. High-temperature uniaxial tensile tests with varying heating rates (4°C/s and 100°C/s) and temperatures (900 - 950°C) were conducted to study the effects of heating parameters on the formability and damage of the material. The microstructure and fracture morphology after high-temperature uniaxial tensile tests were characterised to reveal the evolution mechanisms of elongation and damage. It was found, that fast heating could restrain the phase transformation of α to β during the heating and therefore improve the formability of the Ti6Al4V titanium alloy under hot stamping condition.

Słowa kluczowe:
Ti6Al4V, hot stamping, fracture behaviour, damage evolution

pdf 7275
55. Kopeć M., Brodecki A., Kowalewski Z.L., Digital image correlation as an effective tool for fatigue damage monitoring, BSSM, 15th International Conference on Advances in Experimental Mechanics, 2021-09-07/09-09, Swansea (GB), pp.1-1, 2021nota 7276

The paper aims to investigate an effectiveness of Digital Image Correlation (DIC) technique during fatigue damage development monitoring in X10CrMoVNb9-1 (P91) power engineering steel. It was found, that DIC enables to monitor the fatigue behaviour of steel specimens and accurately indicate the area of potential failure even within initial stage of the fatigue damage development.

Słowa kluczowe:
fatigue development, damage, P91 steel, digital image correlation

pdf 7276
56. Kukla D., Kopeć M., Kowalewski Z.L., Effect of high temperature exposure on the fatigue damage development of X10CrMoVNb9-1 steel for power plant pipes, BSSM, 15th International Conference on Advances in Experimental Mechanics, 2021-09-07/09-09, Swansea (GB), pp.1-2, 2021nota 7277

The aim of this research was to compare the effect of 80 000 h exploitation time in high temperature on mechanical properties and microstructure of X10CrMoVNb9-1 (P91) power engineering steel for pipes. The specimens obtained from two pipes: new, as-received and after exploitation were subjected to fatigue loadings to compare their mechanical responses. Additionally, the uniaxial tensile tests on both types of P91 steel were performed. The microstructure evolution before and after deformation was monitored using optical and scanning electron microscopy. The time intensive, high temperature exposure of P91 power engineering steel led to significant phase transformation and subsequent deterioration of mechanical properties and was further described as a function of the fatigue damage measure, φ, and the fatigue damage parameter D. Further proposed methodology of power exponent approximation of the fatigue damage measure, φ, and fatigue damage parameter D, allowed to successfully determine the fatigue life of P91 steel.

pdf 7277
57. Górniewicz D., Jóźwiak S., Przygucki H., Kopeć M., The concept of improving the fracture toughness of double-phase high entropy alloy produced by high-pulse sintering method U-FAST, BSSM, 15th International Conference on Advances in Experimental Mechanics, 2021-09-07/09-09, Swansea (GB), pp.1-2, 2021nota 7278

In this paper, double-phase high entropy alloys with the BCC solid solution matrix and the C14 structured intermetallic Laves phase precipitates with the were obtained. The mixture of Co, Cr, Fe, Mn, Ti and CuO powders was sintered at 1000°C for 1 min using innovative high-pulse sintering U-FAST method. Such method allows to obtain complex TiCoCrFeMn and TiCoCrFeMn+5 vol.% CuO double-phase high entropy alloys. The followed annealing process led to the significant improvement of the fracture toughness of 46 % for TiCoCrFeMn alloy and 27 % for TiCoCrFeMn+5vol.%CuO alloy.

pdf 7278

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