[Purposes] The crack damage to tunnel lining structure caused by fire generally poses a significant challenge to the maintenance of its structural durability. [Methods] To address this issue, a convex polygon aggregate numerical model of concrete with glazed hollow beads (GIC) consisting of coarse aggregate, mortar, and the interface transition zone was established through the interactive use of MATLAB and COMSOL softwares. The numerical simulation was conducted to investigate the chloride ion transport behavior considering the effect of high temperature and the model validity was then verified. According to the theory of steel reinforcement depassivation life, an evaluation mechanism of post-disaster service life parameter impact was further established. [Findings] The results show that with the increase of the volume fraction of glazed hollow beads, the decrease of the thickness of interfacial transition zone, and the increase of the maximum aggregate diameter, the post-disaster residual service life is improved. Especially, the effect of glazed hollow beads is particularly significant. [Conclusions] According to parameter analysis, the durability limit state function considering the influence of high temperature is finally established through single factor correlation analysis and multivariate nonlinear analysis methods. This study could provide a reference for building structure design and post-disaster life assessment in practical engineering.

Purposes The internally porous and highly thermally stable glazed hollow beads (GHB) can reduce the high temperature damage and deterioration of concrete to a certain extent, and improve the fire resistance of concrete. In order to further clarify the mechanism of GHB in improving the fire resistance of concrete, starting from the meso-scale concrete, we proposed a modeling method for RATIC meso-scale model that can take into account the initial defects and the replacement rate of recycled coarse aggregate (RCA). Methods The effects of RCA replacement rates (0, 50%, 100%), GHB contents (0, 70%, 100%), and porosity (0, 2%, 4%) on the mechanical properties of RATIC after high temperature were explored by utilizing the plastic damage model commonly used at curent stage. Findings The results show that with the increase of fire temperature, the damage distributions of the RATIC specimens under load exhibit a gradually increasing trend, and the damage distribution of the specimens after 500 ℃ is more serious than that before 400 ℃. The addition of GHB alleviates the damage and deterioration inside the concrete to a certain extent, while the addition of RCA exacerbates this phenomenon. In addition, the strength of RATIC specimens gradually decreases with the increase of porosity.

The aim of this study was to create and evaluate a cell model designed for in vitro and in vivo testing of anti-human PD-L1 therapeutic and diagnostic agents' specificity. Materials and Methods. Genetically modified cells expressing human PD-L1 (strain CT26-PD-L1) were obtained by retroviral transduction of murine CT26 carcinoma cells. PD-L1 gene activity was assessed by real-time PCR, and PD-L1 expression on cells was identified by flow cytometry. Cells were tested using recombinant single-domain human anti-PD-L1 antibodies (nanoantibodies) conjugated with radioisotopes 68 Ga or 177 Lu. Immunoreactive fraction and cell internalization of the radioconjugates were evaluated in vitro. For in vivo experiments CT26-PD-L1 cells were transplanted into mice, radioimmunoconjugates were injected 9-14 days later, in 1-48 h the tumors were retrieved and subjected to direct radiometry. Intact CT26 cells not expressing the antigen served as a control. Results. CT26-PD-L1 strain of murine tumor cells expressing human membrane PD-L1 was created. When transplanted into intact BALB/c mice or sublethally irradiated F1(DBAxBALB/c) mice, these cells formed tumors. Thus, a significant advantage of the model was the possibility of in vivo testing of human PD-L1-affinity agents using animals under conventional vivarium conditions. When radioimmunoconjugates were administered to tumor bearing mice, radionuclides accumulated in tumors generated from the transplanted CT26-PD-L1 cells, but not CT26 cells. CT26-PD-L1 cells internalized anti-PD-L1 nanobodies in vitro. Due to a high density of target molecules, CT26-PD-L1 cells allowed both to confirm pharmaceuticals' specificity and to quantify the target-binding fraction of conjugates in a single test. Conclusion. The created cells are the first genetically engineered cells designed to evaluate affinity of anti-human PD-L1 therapeutic and diagnostic agents in Russia. Test results confirmed the model suitability for in vitro and in vivo testing of the specificity of pharmaceuticals targeting human PD-L1.

An Erratum to this paper has been published: https://doi.org/10.1134/S0020441224050014

Acoustic cavitation can be used successfully to implement or intensify physical and chemical processes in liquids in a variety of emerging applications. The investigation of cavitation control methods will assist in the understanding of optimal ways of controlling the onset or prevention of cavitation in related applications. However, most previous experimental studies have concentrated on the cavitation process at specific ultrasound, liquid, hydrostatic pressure, and temperature parameters. Nonetheless, some experimental and theoretical studies show a significant relationship between the influence of these parameters on the onset and development of cavitation processes in liquids. This paper presents an installation for studying acoustic cavitation in various liquids at different ultrasound amplitude-frequency parameters, variable hydrostatic pressure, and temperature. The installation includes four reactors with ultrasound frequencies of 17, 22, 33, and 44 kHz. Ultrasonic waves are produced by a magnetostrictor transducer with a sonotrode immersed in the reactor's substance. The reactor's design allows for varying the hydrostatic pressure from 1 to 10 atm and heating the liquid to 80 °C. As an approval of the installation, the possibility of registering the threshold power of the transducer at the onset of cavitation was considered. The cavitation threshold was investigated using three different liquid loading modes: step-by-step transducer power increase, smooth transducer power increase, and smooth variation of hydrostatic pressure at constant transducer power. Water and sunflower oil were used in the tests. It was found that the installation allows for a study of the frequency dependence of the cavitation onset threshold as well as the effects of hydrostatic pressure and temperature. Specific examples and results are discussed. For example, the possibility of stable control of the onset and attenuation of cavitation by changing the hydrostatic pressure is shown. Furthermore, the results show that the optimal power of the ultrasonic transducer can be chosen based on the available combination of ultrasonic frequency, hydrostatic pressure, and temperature. Some next steps for the installation's development and research are also discussed.

MICA and MICB are non-classical MHC molecules that indicate cellular stress. They act as ligands for NKG2D receptors found on NK cells, thereby triggering a cytotoxic response against damaged, infected, or transformed cells. The production of soluble forms of MICA/MICB occurs via the cleavage of their extracellular domains (ECDs). The expression of MICA/MICB molecules in tumor sections or the levels of their soluble forms in blood have potential as diagnostic tools for cancer. They can predict important clinical outcomes for cancer patients, such as overall and recurrence-free survival. However, their extensive molecular polymorphism complicates the development of monoclonal antibodies (mAbs) for diagnostic use. Therefore, the diagnostic value of mAb-based assays may vary depending on the frequencies of allelic variants in local human populations. We examined the ECD amino acid sequences of more than 280 MICA and 50 MICB allelic variants. Additionally, we identified 172 and 58 single nucleotide polymorphisms (SNPs) located in the coding regions of the respective genes and resulting in amino acid replacements. The most frequent amino acid replacements (> 10%) in the ECD occur at 11 and 4 sites of MICA and MICB, respectively. We found that the frequencies of SNPs in the identified hot spots strongly correlate with each other in different human populations, despite the diversity of allelic variant frequencies. The functional role of only one site is known. The replacement of valine with methionine at position 152 enhances the affinity of MICA to NKG2D receptor. As the hot spots are dispersed throughout the entire ECD sequences, they may play a role other than modulating affinity with the NKG2D receptor interaction. We recommend that Ag sets used to validate anti-MICA/MICB mAbs meet two criteria. First, they should include both MICA and MICB alleles, as these genes have highly similar sequences. Second, the alleles should cover the variability observed in the identified hot spots.

In recent decades, there has been a lot of interest in using construction waste as a source of aggregate for the production of new concrete. Another topic of intense study is the optimal characteristics of reinforcing fibres. However, in contrast to the constant value of the static strength, it is widely known that the dynamic strength of concrete is highly dependent on the strain rate. The wide variety of possible concrete additives further complicates the assessment of the dynamic strength of concrete. Therefore, it is necessary to search for new material parameters that will allow evaluating and comparing the dynamic strength of concrete with various modifications of additivities. In this work, the effects of recycled aggregate and fibres on the fracture critical stress of original, natural aggregate concrete were studied using the incubation time criterion. It was confirmed that by estimating only one additional parameter, the incubation time, which is responsible for the preparatory processes of fracture and is invariant with respect to the history of loading in dynamic and static tests, it is possible to construct the stress/strain rate dependences of the critical stress. The intersections of the theoretical rate dependences of the critical fracture stress under static and dynamic loading considering various percentages of recycled aggregate (from 0% to 100%) and carbon, steel, and synthetic fibres were analysed. The decrease in the dynamic strength of steel- and carbon-fibre-reinforced concretes was interpreted in terms of a change in the incubation time characteristic. The influence of the fibre shape on the strain rate sensitivity of steel- and synthetic-fibre-reinforced concretes was analysed. It is here shown that the incubation time parameter can be considered to be a convenient tool for assessing the influence of recycled aggregate or fibres on the dynamic strength of concrete.

Glioblastoma recurrence is caused by tumor cells resistance which can be initial or acquired resu-lting from therapy. Studies searching the markers that would allow predicting the level of glioblastoma cell therapy resistance are in progress. Complexity of the problem is due to a high heterogeneity of individual tumors as well as due to cellular composition in each tumor. In the present work, comparative study on the influence of temozolomide (in Temodal® form) single exposure on the well-known glioblastoma cell line A172 as well as on new line R1 was performed. Treatment of A172 (highly temozolomide-sensitive cell line) with 0.1 mM temozolomide showed that only individual cells persisted and resumed the proliferation. In R1 glioblastoma, single cells survived and resumed the proliferation upon treatment with 1.0 mM temozolomide. Populations obtained from these proliferating cells were designated as resistant ones. The presence of MGMT enzyme and the expression of genes responsible for chemotherapy resistance and tumor progression (MGMT, ABCB1, ABCC1, ABCG2), and of growth factor genes (VEGF, HGF), as well as the presence of IL-6 and IL-8 cytokines (and their encoding genes) was examined in resistant A172 and R1 cells. In A172 cells, methylated status of MGMT gene promoter and the absence of MGMT gene expression were confirmed. It was firstly shown that R1 glioblastoma was heterogeneous in methylation status of MGMT gene promoter and MGMT enzyme expression. In A172 and R1 resistant cell populations, the level of MGMT gene promoter methylation was lower than in intact cells, while MGMT gene expression was enhanced that could be clue to a greater resistance of these cells to chemotherapy. Expression of most genes connected with chemotherapy resistance and more aggressive course of the disease, as well as of growth factors genes and interleukin genes in resistant A172 cells was higher than in intact cells. In contrast, in resistant R1 cells, expression of the same genes (excluding ABCC1 and VEGF, in which the expression level changed insignificantly) was lower than in intact cells. Our results confirmed the significance of MGMT in formation of glioblastoma cell resistance to temozolomide. Prognostic value of other studied parameters is still considered ambiguous.

One of the most important characteristics of radiolabeled antibodies and their derivatives is the size of the immunoreactive fraction. Measuring this parameter requires a high density of target molecules, which is rarely achievable with tumor cells. The solution to the problem of radioimmunoconjugate testing was the creation of recombinant cells carrying human endoglin (CD105). The recipients of the endoglin gene ( ENG ) were rat C6 glioma cells, which are characterized by ease of cultivation and high transfection efficiency. The obtained C6-ENG cells carried 1.3 × 10 6 CD105 molecules on the membrane and were used to determine the immunoreactive fraction of 68 Ga and 89 Zr radiolabeled anti-CD105 monoclonal antibodies and their Fab-fragments. The creation of stable recombinant cell lines for in vitro testing the specific activity of radiolabeled antibodies and their derivatives seems promising for the development of new radiopharmaceuticals.

. The research reveals the existence of a constant characteristic time of preparatory microstructural processes before the onset of macro-failure at various high loading rates of brittle and quasi-brittle materials. The presence of this characteristic is analysed based on available data in the literature from dynamic tests for uniaxial compression and splitting. It is shown that the characteristic time can be determined experimentally and used to calculate the strain rate dependencies of either critical failure stresses or time to failure, at least in the case of linearly growing loads. In addition, it is discussed that the presence of this constant parameter opens up a prospective opportunity for research and development of new methods for assessing the structural-temporal and scale characteristics of the strength and failure of materials under dynamic loads.

Graphene-doped ceramic composites with mixed electronic-ionic conductivity are currently attracting attention for their application in electrochemical devices, in particular membranes for solid electrolyte fuel cells with no necessity to use the current collector. In this work, composites of the Y2O3-ZrO2 matrix with graphene-augmented γ-Al2O3 nanofibres (GAlN) were spark plasma sintered. The conductivity and electrical stability in cyclic experiments were tested using electrical impedance spectroscopy. Composites with 0.5 and 1 wt.% GAlN show high ionic conductivity of 10−2–10−3 S/cm at 773 K. Around 3 wt.% GAlN percolation threshold was achieved and a gradual increase of electronic conductivity from ~10−2 to 4 × 10−2 S/cm with an activation energy of 0.2 eV was observed from 298 to 773 K while ionic conductivity was maintained at elevated temperatures. The investigation of the evolution of conductivity was performed at 298–973 K. Besides, the composites with 1–3 wt.% of GAlN addition show a remarkable hardness of 14.9–15.8 GPa due to ZrC formation on the surfaces of the materials.

Fire occurrence may result in significant micro/meso-scale damage inside the concrete structure, including coarsening of pores and evolution of cracks. Such micro/meso-scale damage greatly impacts the load-bearing capacity and durability of the concrete structure. The lightweight, high-strength, internally porous, and highly thermally stable glazed hollow beads (GHB) may alleviate the cracking around the pores boundary and the mortar matrix due to their special pressure release effect, thus improving the fire resistance of concrete. In order to further investigate the reinforcing mechanism of GHB to the fire resistance of concrete, the CT scanning tests on recycled aggregate concrete mixed with glazed hollow beads (RATIC) before and after the high-temperature exposure were carried out in this paper. Firstly, the image segmentation method was used to obtain the extraction images of concrete pores and cracks. Then, the evolution trends of the porosity, average pore diameter, crack fraction, crack density, and average crack width were analyzed, and the correlation of these parameters with the residual compressive strength was discussed. Finally, a thermal damage model of RATIC considering the influence of micro/meso-scale damage and temperature was developed. The results showed that the recycled coarse aggregate (RCA) addition aggravates the evolution of the pores and cracks characteristics, while the GHB incorporation can alleviate this phenomenon to a certain extent and improve the high-temperature deterioration resistance of concrete. In addition, the proposed thermal damage model of RATIC has good applicability.

Membrane molecules PD-L1 and PD-L2, ligands of T lymphocytes PD1 receptor, perform immunoregulatory functions. Their binding to the receptor leads to inhibition of proliferation, reduction of cytokine production, cytotoxic response, and apoptosis of T lymphocytes. The cells of many tumors, regardless of their histogenesis, express PD-L1 molecules, thus limiting the development of an anti-tumor immune response. Glioblastomas are highly malignant recurrent tumors of the central nervous system. The main sources of glioblastoma recurrence are resistant tumor cells initially present in gliomas with heterogeneous cellular composition, as well as resistant cells that are formed during therapy. Increasing the dose of cytostatic drugs or radiation during relapse therapy is not effective in glioblastomas. It has been shown for a number of tumors, including ovarian cancer and non-small cell lung cancer, that drugs preventing PD-L1/PD1 interaction are effective in the treatment of neoplasms resistant to chemo- and radiotherapy. Immunotherapy using drugs that inhibit the binding of PD-L molecules to their receptor is considered as a way to overcome the resistance of glioblastomas to therapy. The aim of this work was to assess the level of PD-L1 and PD-L2 gene expression in resistant glioblastoma cells lines A172, R1, T2 and T98G, which resumed proliferation after exposure to the maximum for each line, sublethal doses of cytostatic drugs (fotemustine and temozolomide), fractionated or single gamma irradiation. A172 line belongs to glioblastomas that are highly sensitive to these influences, T98G is a highly resistant cell line, while R1 and T2 lines occupy an intermediate position. In intact glioblastoma A172, R1, and T2 cells the level of PD-L1 and PD-L2 gene expression was equally high, while in T98G cells it was significantly lower. Exposure of A172 and R1 glioblastoma lines to cytostatic drugs or irradiation did not significantly change the level of PD-L1 and PD-L2 genes expression typical for intact cells. In T2 glioblastoma cells, and especially in T98G cells, a significant increase in expression of these genes was found, most pronounced for PD-L2 gene. This increase in expression may indicate an enhanced malignancy of resistant T2 and T98G cells. High expression of the genes responsible for the production of PD-L1 and PD-L2, which limit the cytotoxic response against tumor cells, is a prerequisite for the use of drugs targeted against PD-L1 and PD-L2 for the elimination of resistant cells in glioblastoma.

Due to their higher strength and lighter weight compared to conventional metals, graphene-nickel (Gr-Ni) composites have recently gained growing interest for use in the automotive and aerospace industries. Homogeneous Gr dispersion, the metal powder dispersity and processing conditions play a key role in obtaining the desired grain size distribution, an amount of high angle grain boundaries thus reaching the desired balance between strength and plasticity of the composite. Here, we report an approach to fabricating graphene-nickel composites with balanced strength and ductility through the microstructure optimization of the nickel matrix. A graphite platelets (GP) content of 0.1–1 wt.% was used for the optimization of the mechanical properties of the material. In situ, conversion GP-to-Gr was performed during the milling step. This paper discusses the effect of bimodal nano- and micro-sized Ni (nNi and mNi) on the mechanical properties and microstructure of Gr-Ni composites synthesized using a modified powder metallurgy approach. Specimens with varied nNi:mNi ratios were produced by two-step compaction and investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, electron back-scattered diffraction (EBSD) and nanoindentation. The best combination of ultimate tensile strength (UTS), yield limit (YL), elongation and hardness were obtained for 100nNi and 50nNi matrices, and the best composites were those with 0.1% graphene. The addition of more than 0.5 wt.% GP to the nickel matrix induces the fracture mechanism change from tensile to brittle fracture. Dedicated to the 300th anniversary of the St. Petersburg University Foundation.

The acoustic cavitation of fluids, as well as related physical and chemical phenomena, causes a variety of effects that are highly important in technological processes and medicine. Therefore, it is important to be able to control the conditions that allow cavitation to begin and progress. However, the accurate prediction of acoustic cavitation is dependent on a complex relationship between external influence parameters and fluid characteristics. The multiparameter problem restricts the development of successful theoretical models. As a result, it is critical to identify the most important parameters influencing the onset of the cavitation process. In this paper, the ultrasonic frequency, hydrostatic pressure, temperature, degassing, density, viscosity, volume, and surface tension of a fluid were investigated using machine learning to determine their significance in predicting acoustic cavitation strength. Three machine learning models based on support vector regression (SVR), ridge regression (RR), and random forest (RF) algorithms with different input parameters were trained. The results showed that the SVM algorithm performed better than the other two algorithms. The parameters affecting the active cavitation nuclei, namely hydrostatic pressure, ultrasound frequency, and outgassing degree, were found to be the most important input parameters influencing the prediction of the cavitation threshold. Other parameters have a minor impact when compared to the first three, and their role can be compensated for by alternative variables. The further development of the obtained results provides a new way to optimize and improve existing theoretical models.

One of the modern methods of treating patients with primary and recurrent brain tumors is radiosurgical irradiation using Gamma Knife, which allows therapeutic doses to be delivered to tumors not exceeding 2.5 cm in diameter in 1–2 sessions. Tumor cells on the periphery of this tissue volume that receive lower radiation doses can resume proliferation and serve as a source of recurrence. The increase of radiation dose may cause necroses formation and a worsening prognosis. The properties of glioblastoma cells that survive and resume proliferation long after stereotactic irradiation are still poorly known. The aim of the work was to evaluate the expression of IL-6 and IL-8 by glioblastoma A172, R1, T2, and T98G cell lines that resumed proliferation after sublethal Gamma Knife irradiation. Cells were irradiated once at doses ranging from 6 to 16 Gy, and then cultured for 40 days. Cell number was counted weekly; lethal and sublethal irradiation doses for each glioblastoma cell line were determined. In cultures descendant from proliferation of single most resistant cells, the level of IL-6 and IL-8 secretion after 96 hours cultivation (ng/1000 cells) was determined by ELISA. The cells of all four glioblastoma lines secreted IL-6 and IL-8 into culture medium. The highest production of cytokines, never before demonstrated for glioblastomas, was discovered in R1 cells. Glioblastoma T2 also had high interleukin production levels. In contrast to these lines, glioblastoma A172 (highly sensitive to the action of cytostatic drugs and radiation) secreted IL-6 at 30 times lower level than R1 cells. Glioblastoma T98G (highly resistant to the action of cytostatic drugs and radiation) also exhibited low interleukins production level. R1, T2, and T98G glioblastoma cells that resumed proliferation after irradiation had increased secretion of IL-6 and, to a lesser extent, IL-8. The dependence of cytokine production increase on irradiation dose for these cells was not linear. In contrast, A172 cells reduced IL-6 and IL-8 secretion under irradiation. The multidirectional changes in IL-6 and IL-8 production by cells of different glioblastoma lines were long-term and persisted for more than a month. The presented results cast doubt on the possibility to use IL-6 and IL-8 production by glioblastoma cells as potential biomarkers for early diagnosis, therapy monitoring as well as prognostic markers of the disease course.

In recent years, additive manufacturing of products made from 5000 series alloys has grown in popularity for marine and automotive applications. At the same time, little research has been aimed at determining the permissible load ranges and areas of application, especially in comparison with materials obtained by traditional methods. In this work, we compared the mechanical properties of aluminum alloy 5056 produced by wire-arc additive technology and rolling. Structural analysis of the material was carried out using EBSD and EDX. Tensile tests under quasi-static loading and impact toughness tests under impact loading were also carried out. SEM was used to examine the fracture surface of the materials during these tests. The mechanical properties of the materials under quasi-static loading conditions exhibit a striking similarity. Specifically, the yield stress σ0.2 was measured at 128 MPa for the industrially manufactured AA5056_IM and 111 MPa for the AA5056_AM. In contrast, impact toughness tests showed that AA5056_AM KCVfull was 190 kJ/m2, half that of AA5056_IM KCVfull, which was 395 kJ/m2.

High temperatures can have a profound impact on the internal pore structure of concrete, which consequently deteriorates its mechanical properties. In order to examine the effect of high temperatures on the microstructural characteristics and residual mechanical properties of recycled aggregate concrete mixed with glazed hollow beads (RATIC), the cube compressive strength test and CT test were carried out on RATIC specimens treated at the different temperatures. Through three-dimensional reconstruction of CT images, the three-dimensional microstructure of the RATIC after the high-temperature treatment were obtained to analyze the variation in its internal pores with the temperature, and to elaborate on the mechanism for the deterioration of its mechanical properties from the perspective of microstructural characteristics of pores. The results show that the glazed hollow bead (GHB) can slow down the spread of heat in the concrete and renders a positive effect on the heat-induced damage resistance of concrete. The incorporation of the GHB effectively optimizes the pore structure of the RATIC and reduces the pore distortion caused by the high temperature. In addition, the quantitative relationship between the pore characteristic parameters and the residual compressive strength of RATIC was investigated, and a computational model was obtained to characterize the relationship between the pore characteristic parameters and the residual compressive strength using nonlinear analysis.

Fully stabilized zirconia/graphene composites are very promising advanced structural materials having mixed ion–electron conductivity for energy storage and energy conversion applications. The existing methods of the composite manufacturing have a number of disadvantages that limit their practical use. Thus, the search for new sintering methods is an actively developing area. In this work, we report for the first time the application of the SiC powder bed sintering technique for fully stabilized zirconia (YSZ) composite fabrication. The reduced graphene oxide (rGO) was used as a graphene derivative. As a result, well-formed ceramics with high density and crystallinity, the maximal microhardness of 13 GPa and the values of the ionic conductivity up to 10−2 S/cm at 650 °C was obtained. The effects of the sintering conditions and rGO concentration on the microstructure and conductivities of ceramics are discussed in detail. The suggested powder bed sintering technique in a layered graphite/SiC/graphite powder bed allowed well-formed dense YSZ/rGO ceramics fabrication and can become a suitable alternative to existing methods for various oxide ceramic matrix composite fabrication: both conventional sintering and non-equilibrium (SPS, flash sintering) approaches.

Nickel aluminides, namely NiAl, Ni3Al and NiAl3, based functional materials have the attractive properties for structural applications at elevated temperatures. However, the intermetallics in the Al-Ni system are rather brittle which limits their practical applications. Graphene and its derivatives are known to be ex-cellent reinforcements for various metallic and ceramic matrices. In the present work 0.5 wt% reduced graphene oxide (rGO) was incorporated in the Al-Ni system for the first time using modified powder metallurgy technique. Phase composition, structures of powders and composite intermetallic materials were investigated via SEM, EDS, XRD, Raman spectroscopy and hydrostatic weighing. The effect of rGO on the phase formation, microstructure and mechanical properties of the composites was discussed. Via XRD it was shown, that rGO favors the formation of AlNi, Ni3Al and Al3Ni compounds in the Al-Ni system. The Al3Ni2 was shown to be first intermediate phase appearing in the phase sequence. Due to the reinforcement effect of rGO, 80nNi-rGO composite showed about 5 times higher tensile strength, about 3 times higher Young's modulus and improved elongation as compared to the same composition without rGO. The 40nNi-rGO and 51nNi-rGO composites exhibited superior hardness of 297 +/- 28 HV0.3, 561 +/- 121 HV0.3 and 640 +/- 118 HV0.3.(c) 2022 Elsevier B.V. All rights reserved.