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Number of results: 21
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Abstract

In order to achieve extended life of asphalt pavement, one of key points is to achieve a good bonding between it’s components. This research paper presents findings on the topic of influence of polyethylene bitumen modification on the adhesion between bitumen and aggregate. A novel method of quantifying the bitumen coated area, based on computer image analysis, has been developed for this study. Two different methods of adhesion testing were employed, namely boiling water method and the rolling bottle method. Aggregates used in this study were granite and limestone. Based on 108 measurements, it was concluded that polyethylene modification has a negative impact on binder aggregate adhesion.

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Authors and Affiliations

D. Brożyna
K. J. Kowalski
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Abstract

Hybryd PLD method was used for deposition high quality thin Ti, TiN, Ti(C,N) and DLC coatings. The kinetic energy of the evaporated particles was controlled by application of variation of different reactive and non reactive atmospheres during deposition. The purpose was to improve adhesion by building a bridge between the real ceramic coating and the substrate. A new layer composition layout was proposed by application of a buffer, starting layer. Advanced HRTEM investigation based on high resolution transmission electron microscopy was used to reveal structure dependence on specific atmosphere in the reactive chamber. New experimental technique to examine the crystallographic orientation based on X-ray texture tomography was applied to estimate contribution of the atmosphere to crystal orientation. Using Dictyostelium discoideum cells as a model organism for specific and nonspecific adhesion, kinetics of shear flow-induced cell detachment was studied. For a given cell, detachment occurs for critical stress values caused by the applied hydrodynamic pressure above a threshold. Cells are then removed from the substrate with an apparent first-order rate reaction that strongly depends on the stress. The threshold stress depends on cell size and physicochemical properties of the substrate, but it is not affected by depolymerization of the actin and tubulin cytoskeleton.

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Authors and Affiliations

R. Major
F. Bruckert
J.M. Lackner
W. Waldhauser
M. Pietrzyk
B. Major
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Abstract

An alternative approach of the determining of conditions of safe stability loss of rectilinear motion of a wheeled vehicle model with controlled wheel module in the sense of N.N. Bautin is considered. The slipping forces are presented accurate within cubic expansion terms in the skid angles. Terms and conditions of safe stability loss depend on the ratio between the coefficients of resistance to the skid, the adhesion coefficients in the transverse direction of the axes and the parameter of torsional stiffness of the controlled wheel module. The presented approach to the analysis of real bifurcations related to the divergent loss of rectilinear motion mode stability has a clear geometric pattern: if in the vicinity of rectilinear motion at subcritical speed, there are additionally two unstable circular stationary states, then the stability limit is of dangerous nature in the sense of N.N. Bautin; if two circular stationary modes exist at supercritical speed, the limit of the stability loss in the parameter space of the longitudinal velocity is safe in the sense of N.N. Bautin. Analysis of the number of stationary modes in the vicinity of the critical velocity of rectilinear motion is performed for the obtained determining equation - cubic binomial.
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Authors and Affiliations

Alexandr Kravchenko
Vladimir Verbitskii
Valery Khrebet
Natalia Velmagina
Andrey Muranov
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Abstract

AISI 316L steel was subjected to nitrocarburizing under glow discharge conditions, which was followed by DLC (diamond-like carbon) coatings deposition using the same device. The coatings were applied under conditions of direct current and pulsed glow discharge. In order to determine the influence of the produced nitrocarbon austenite layer and the type of discharge on the microstructure and mechanical properties of the coatings, the following features were analysed: surface roughness, coating thickness, structure, chemical composition, adhesion and resistance to frictional wear. For comparison purposes, DLC coatings were also deposited on steel without a nitrocarburised layer. The obtained results indicate a significant influence of the type of glow discharge on the roughness, hardness, nitrogen content and of the nitrocarburised layer on the resistance to wear by friction and adhesion of the produced coatings.
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Authors and Affiliations

T. Borowski
1
ORCID: ORCID
K. Kulikowski
1
ORCID: ORCID
M. Spychalski
1
ORCID: ORCID
K. Rożniatowski
1
ORCID: ORCID
B. Rajchel
2
B. Adamczyk-Cieślak
1
ORCID: ORCID
T. Wierzchoń
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Materials Science and Engineering, 141 Wołoska Str., 02-507 Warszawa, Poland
  2. Polish Academy of Sciences, Institute of Nuclear Physics, Poland
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Abstract

The paper presents the test results of molding compounds, sand casting molds and their analysis. The subject of testing was compound containing furan resins prepared according to the following recipe: matrix – regenerate 90% + fresh sand – 10%, furan resin – 1.10% by weight, hardener – 0.40% by weight. The impact of adhesive type and its quantity (Quan = 0.90, 1.1 and 1.5%) on the strength indexes of molding compound subject to densification was analyzed. The publication presents the test results: tensile strength Rm, compressive strength Rc and flexural strength Rg, as well as compound permeability as function of its density. The analysis also covers the impact of density level on mold strength and the distribution of density level along the mold height.

Based on the test results, it was found that the best method to obtain high strength molds made from compounds with chemical adhesives was to densify it by vibrating the system: match plate – molding flask – compound filling the mold. The effectiveness of this densification method depends on the amplitude and frequency of vibrations.

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Authors and Affiliations

Ł. Petrus
A. Bulanowski
J. Kołakowski
ORCID: ORCID
M. Urbanowicz
J. Sobieraj
M. Jelonek
M. Brzeżański
ORCID: ORCID
J.S. Zych
K. Janerka
ORCID: ORCID
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Abstract

Background: Studies on the effect of root canal rinsing protocols on fiber post bonding to dentin are inconclusive. This study reports investigation of this topic. Objectives: to determine effects of irrigation protocol by means of a push-out test on the strength of adhesion between the post and dentin in an in vitro study.
Materials and Method: Thirty human single-rooted teeth were prepared using hand instruments and the step-back technique, filled with gutta-percha, sealed with AH Plus (Dentsply), and divided into three groups: A: rinsed with NaCl; B: rinsed with 2% chlorhexidine (CHX); C: not rinsed before cementa-tion of posts. The fiber posts were set using RelyX and Built-it. The tooth roots were sliced and the push- out test was performed. The area of contact between the post and dentin was calculated and the destroying force was established. The results were statistically analyzed.
Results: The mean adhesive strength was 10.69 MPa in group A, 16.33 MPa in group B, and 16.72 MPa in C. The adhesive strength in group B and C was statistically significantly higher than in group A (p = 0.0016, ANOVA).
Conclusion: Rinsing root canals with CHX seems to be the most effective method prior to setting a fiber post.
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Bibliography

1. Asmussen E., Peutzfeldt A., Heitmann T.: Stiffness, elastic limit, and strength of newer types of endodontic posts. Journal of Dentistry. 1999; 27: 275–278.
2. Bateman G., Ricketts D.N., Saunders W.P.: Fibre-based post systems: a review. Br Dent J. 2003; 195: 43–48.
3. Schwartz R.S., Robbins J.W.: Post placement and restoration of endodontically treated teeth: a literature review. J Endod. 2004; 30: 289–301.
4. Skupien A., Sarkis-Onofre R., Cenci S., Morales R., Pereira-Cenci T.: A sys.ematic review of factors associated with the retention of glass fiber posts. Braz Oral Res. 2015; 29: 1–8.
5. Ryniewicz W., Ryniewicz A.M., Bojko Ł.: The effect of a prosthetic crown’s design on the accuracy of mapping an abutment teeth’s shape. Meas. 2016; 91: 620–627.
6. Bitter K., Aschendorff L., Neumann K., Blunck U., Sterzenbach G.: Do chlorhexidine and ethanol improve bond strength and durability of adhesion of fiber posts inside the root canal? Clin Oral Investig. 2014; 18: 927–934.
7. Haragushiku G.A., Back E.D., Tomazinho P.H., Baratto Filho F., Furuse A.Y.: Influence of antimicrobial solutions in the decontamination and adhesion of glass-fiber posts to root canals. J Appl Oral Sci. 2015; 23: 436–441.
8. Stape T.H.S., de Souza Menezes M., Aguiar F.H.B., Quagliatto P.S., Soares C.J., Martins L.R.M.: Long- term effect of chlorhexidine on the dentin microtensile bond strength of conventional and self- adhesive resin cements: A two-year in vitro study. Int J Adhes Adhes. 2014; 50: 228–234.
9. Toman M., Toksavul S., Tamac E., Sarikanat M., Karagozoglu I.: Effect of chlorhexidine on bond strength between glass-fiber post and root canal dentine after six month of water storage. Eur J Prosthodont Restor Dent. 2014; 22: 29–34.
10. Cecchin D., Farina A.P., Souza M.A., Da Cunha Pereira C.: Effect of root-canal sealer on the bond strength of fiberglass post to root dentin. Acta Odontol Scand. 2011; 69: 95–100.
11. Cecchin D., de Almeida J.F., Gomes B.P., Zaia A.A., Ferraz C.C.: Influence of chlorhexidine and ethanol on the bond strength and durability of the adhesion of the fiber posts to root dentin using a total etching adhesive system. J Endod. 2011; 37: 1310–1315.
12. Cecchin D., Farina A.P., Giacomin M., Vidal C. de M., Carlini-Junior B., Ferraz C.C.: Influence of chlorhexidine application time on the bond strength between fiber posts and dentin. J Endod. 2014; 40: 2045–2048.
13. Cecchin D., Giacomin M., Farina A.P., Bhering C.L., Mesquita M.F., Ferraz C.C.: Effect of chlorhexidine and ethanol on push-out bond strength of fiber posts under cyclic loading. J Adhes Dent. 2014; 16: 87–92.
14. Ekambaram M., Yiu C.K., Matinlinna J.P., Chang J.W., Tay F.R., King N.M.: Effect of chlorhexidine and ethanol-wet bonding with a hydrophobic adhesive to intraradicular dentine. J Dent. 2014; 42: 872–882.
15. Gomes Franca F.M., Vaneli R.C., Conti C. de M., Basting R.T., do Amaral F.L., Turssi C.P.: Effect of Chlorhexidine and Ethanol Application on Long-term Push-out Bond Strength of Fiber Posts to Dentin. J Contemp Dent Pract. 2015; 16: 547–553.
16. Leitune V.C., Collares F.M., Werner Samuel S.M.: Influence of chlorhexidine application at longitudinal push-out bond strength of fiber posts. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010; 110: e77–81.
17. Lindblad R.M., Lassila L.V., Salo V., Vallittu P.K., Tjaderhane L.: Effect of chlorhexidine on initial adhesion of fiber-reinforced post to root canal. J Dent. 2010; 38: 796–801.
18. Kang H.-J., Moon H.-J., Shin D.-H.: Effect of different chlorhexidine application times on microtensile bond strength to dentin in Class I cavities. Restor Dent Endod. 2012; 37: 9–15.
19. Goracci C., Grandini S., Bossu M., Bertelli E., Ferrari M.: Laboratory assessment of the retentive potential of adhesive posts: a review. J Dent. 2007; 35: 827–835.
20. Baldea B., Furtos G., Antal M., Nagy K., Popescu D., Nica L.: Push-out bond strength and SEM analysis of two self-adhesive resin cements: An in vitro study. J Dental Sci. 2013; 8: 296–305.
21. Bitter K., Hambarayan A., Neumann K., Blunck U., Sterzenbach G.: Various irrigation protocols for final rinse to improve bond strengths of fiber posts inside the root canal. Eur J Oral Sci. 2013; 121: 349–354.
22. Casselli D.S., Borges M.G., Menezes M.S., Faria-e-Silva A.L.: Effect of cementation protocol on push- out bond strength of fiber posts to root canal. Appl Adhes Sci. 2014; 2: 15.
23. Cecchin D., de Almeida J.F., Gomes B.P., Zaia A.A., Ferraz C.C.: Effect of chlorhexidine and ethanol on the durability of the adhesion of the fiber post relined with resin composite to the root canal. J Endod 2011; 37: 678–683.
24. Kim Y.H., Shin D.H.: Effect of chlorhexidine application on the bond strength of resin core to axial dentin in endodontic cavity. Restor Dent Endod. 2012; 37: 207–214.
25. Lima J.F., Lima A.F., Humel M.M., Paulillo L.A., Marchi G.M., Ferraz C.C.: Influence of irrigation protocols on the bond strength of fiber posts cemented with a self-adhesive luting agent 24 hours after endodontic treatment. Gen Dent. 2015; 63: 22–26.
26. Wang L., Pinto T.A., Silva L.M., et al.: Effect of 2% chlorhexidine digluconate on bond strength of a glass-fibre post to root dentine. Int Endod J. 2013; 46: 847–854.
27. de Araujo D.F., Chaves L.P., Bim O. Jr., et al.: Influence of 2% chlorhexidine digluconate on bond strength of a glass-fibre post luted with resin or glass-ionomer based cement. J Dent. 2014; 42: 735– 741.
28. Sahinkesen G., Erdemir U., Oktay E.A., Sancakli H.S.: The effect of post surface silanization and luting agents on the push-out bond strengths of adhesively inserted fiber reinforced posts. Int J Adhes Adhes 2011; 31: 265–270.
29. Lindblad R.M., Lassila L.V., Salo V., Vallittu P.K., Tjaderhane L.: One year effect of chlorhexidine on bonding of fibre-reinforced composite root canal post to dentine. J Dent. 2012; 40: 718–722.


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Authors and Affiliations

Bartosz Ciapała
1
Krzysztof Górowski
2
Wojciech I. Ryniewicz
2
Andrzej Gala
2
Jolanta E. Loster
2

  1. Department of Integrated Dentistry, Institute of Dentistry, Jagiellonian University Medical College, Kraków, Poland
  2. Department of Dental Prosthetics and Orthodontics, Institute of Dentistry, Jagiellonian University Medical College, Kraków, Poland
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Abstract

The strength of conveyor belts splices made in mines rarely reaches full belt strength. It consists of a number of factors. The primary is the method of their construction and proper selection of ingredients. The significant impact has also has splice quality covering both keeping proper geometry matched to the belt construction and belts working conditions and adherence to the best practices in the field of technologies of their construction.Difficult conditions in underground mines and pressure on reducing conveyor downtime (avoiding production losses) is reflected by a drop in static and dynamic splices strength. This is confirmed by numerous studies of belt splices strength and fatigue life conducted in the Laboratory of Belt Conveying (LTT) within the framework of research and expert opinions commissioned by belt manufacturers and their users. The consequence of too insufficiently low belt splices strength is their low durability, decreasing reliability and, consequently, higher mining transportation costs. Belt splices are in fact the weakest link in the serial structure which form closed loops of interconnected belt sections working in series of conveyors transporting excavated material in the mine. The article presents the results of simulation analyzes analyses investigating how the increase of belt splices durability may contribute to the reduction of transportation costs in the underground mines.

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Authors and Affiliations

Mirosław Bajda
Ryszard Błażej
Leszek Jurdziak
Monika Hardygóra
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Abstract

The paper reviews selected methods of agricultural biogas production and characterizes their technical and technological aspects. The conditions of the anaerobic fermentation process in the reactor with adhesive skeleton bed were analyzed. The required technological criteria for the production of biogas from a substrate in the form of pig slurry were indicated. As part of experimental studies, evaluation of the biogas replacement resistance coefficient and the permeability coefficient as a function of the Reynolds number were made. The method of numerical simulation with the use of a tool containing computational fluid dynamics codes was applied. Using the turbulent flow model – the RANS model with the enhanced wall treatment option, a numerical simulation was carried out, allowing for a detailed analysis of hydrodynamic phenomena in the adhesive skeleton bed. The paper presents the experimental and numerical results that allow to understand the fluid flow characteristics for the intensification of agricultural biogas production.
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Bibliography

[1] Grzegorzewicz J., Gruszecki Z., Sciezynski H., Cieslak R., Smaga M., Jurkowski A., Matyja K., Papuga W.: Bubble Reactor. Patent Office of the Republic of Poland. Patent Application P.174663, 1994 (in Polish).
[2] http://pfee.de/en/cellroll/ (accessed 15 Apr. 2018).
[3] http://www.ows.be/household_waste/dranco/ (accessed 15 Apr. 2018).
[4] https://www.hz-inova.com/hitachi-zosen-inova-doubles-up-with-contract-forsecond-kompogas-plant-in-peloponnese-region/ (accessed 12 May 2018).
[5] http://www.valorgainternational.fr/en/mpg3-128079–VALORGA-SANAEROBIC-DIGESTION-PROCESS.html (accessed 12 May 2018).
[6] Oniszk-Popławska A., Matyka M.: Final report on the field research. “Comprehensive assessment of the conditions for biogas production in the Lubelskie Voivodeship”. Regional Economic Change Management System, 2012 (in Polish).
[7] Jedrczak A.: Biological waste treatment. Przeglad Komunalny (2001), 6, 89–92 (in Polish). [8] Wałowski G.: Developing technique anaerobic digestion in the contex of renewable energy sources. In: Proc. 26th Eur. Biomass Conf., Copenhagen, 14-17 May 2018, 798–808
[9] Kowalczyk-Jusko A.: Biogas plants an opportunity for agriculture and the environment. Fundacja na rzecz Rozwoju Polskiego Rolnictwa, 2013 (in Polish).
[10] Głodek E.: Report on the EU project POKL.08.02.01-16-028 / 09 Sources of Energy in the Opole region 2013 promotion, technologies, support, implementation. Institute of Ceramics and Building Materials, Opole 2010. (in Polish).
[11] den Boer E., Szpadt R.: Biogas plants as an opportunity for agriculture and the environment]. In: Proc. Conf. on 24 Oct. 2013, Dolnoslaski Osrodek Doradztwa Rolniczego we Wrocławiu (in Polish).
[12] Karłowski J., Kliber A., Myczko A., Golimowska R., Myczko R.: Agronomy in the sustainable development of modern agriculture]. In: Proc. 4th Sci. Conf. of the Polish Agronomic Society, Warszawa, 5-7 Sept. 2011 (in Polish).
[13] Myczko A., Myczko R., Kołodziejczyk T., Golimowska R., Lenarczyk J., Janas Z., Kliber A., Karłowski J., Dolska M.: Construction and Operation of Agricultural Biogas Plants. Wyd. ITP, Warszawa Poznan 2011.
[14] Kołodziejczyk T., Myczko R., Myczko A.: Use of residual non-food cellulosic material for biogas production. Ciepłownictwo, Ogrzewanictwo, Wentylacja 42(2011), 9, 360–363. (in Polish).
[15] Wałowski G.: Interpretation of the mechanism of biogas flow through an adhesive bed in analogy to gas-permeability for a structural model of a porous material. Int. J. Curr. Res. 10(2018), 12, 76225–76228.
[16] Wałowski G.: Multi-phase flow assessment for the fermentation process in monosubstrate reactor with skeleton bed. J. Water Land Dev. 42(2019), 7-9, 150–156.
[17] Myczko A., Kliber A., Tupalski L.: The latest achievements in the field of renewable energy sources along with the presentation of barriers to the implementation of research results into business practice. In: The Latest Developments in the Field of RES, Including the Presentation of Barriers to the Implementation of Research Results in Business Practice and Suggestions for their Solutions (B. Mickiewicz, Ed.), Koszalin 2012 (in Polish).
[18] Wałowski G., Borek, K. Romaniuk W., Wardal W.J., Borusewicz A.: Modern Systems of Obtaining Energy – Biogas. Wydawnictwo Wyzszej Szkoły Agrobiznesu w Łomzy, Łomza 2019 (in Polish).
[19] Strzelecki T., Kostecki S., Zak S.: Modelling of flows through porous media. Dolnoslaskie Wydawnictwo Edukacyjne, Wrocław, 2008. (in Polish).
[20] https://www.ansys.com/products/fluids/ansys-fluent (accessed 15 Apr. 2018).
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Authors and Affiliations

Grzegorz Wałowski
1
ORCID: ORCID

  1. Institute of Technology and Life Sciences, Falenty, Department of Renewable Energy, Poznań Branch, ul. Biskupińska 67, 60-463 Poznań, Poland
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Abstract

Postoperative adhesion (POA) is a common and well-known complication with an estimated risk of 50-100%. The antioxidant effect of n-acetyl-cysteine (NAC) can increase intracellular glutathione levels, thereby reducing adhesion. This study was conducted to compare the outcomes of NAC nanoparticles (Nano-NAC) on intra-abdominal adhesion (IAA) after laparotomy in rat. A total of 25 male Wistar rats were randomized into five groups: 50 mg/kg Nano-NAC, 75 mg/kg Nano-NAC, 150 mg/kg Nano-NAC, NAC and control. During the surgical procedure, some sections (2×2cm) were collected through abdominal midline incision to ensure the infliction of peritoneal damage by a standard adhesion. Macroscopic evaluation was performed on the 14th and 28th day and blood samples were collected to evaluate the inflammatory factor (C-reactive protein) on days 0, 14 and 28. According to the serologic results (CRP test), C-reactive protein was at highest level in 150 mg/kg Nano-NAC and control groups and at lowest level in 50 mg/kg Nano-NAC and 75 mg/kg Nano-NAC groups (p<0.001). The macroscopic evaluation results showed that frequency of adhesion bands was significantly lower in 50 mg/kg Nano-NAC group than the control at the intervals. Results showed that the intraperitoneal administration of lower Nano-NAC dosages (50 and 75 mg/kg) had a major role in the management of postoperative inflammation. Nano-NAC administration was proved feasible, safe and effective in reduction of the C-reactive protein level.

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Authors and Affiliations

Sh. Shahzamani
AR. Jahandideh
GhR. Abedi
A. Akbarzadeh
S. Hesaraki
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Abstract

To this day, most of the papers related to hybrid joints were focused on single and double lap joints in which shear deformation and degradation was the dominant phenomenon. However, in real constructions, complex state of loads can be created by: a) torsion with shear, b) bending with shear, c) torsion with tensile.

Analytical and numerical computation for simple mechanical joints is known, however, the introduction of an adhesive layer to this joint makes the load transferred both through: (1) the adhesive and (2) mechanical fasteners. There is also an interaction between the amount and stiffness of mechanical fasteners and the strength of the adhesive layer.

The paper presents the results of numerical calculations for the bending with shear type of load for the hybrid structural joint and corresponding simple joints by: (1) pure adhesion and (2) rivets with different quantity maintaining the same cross-sectional area. A total of 9 simulations were performed for: (1) 4 types of pure rivets connections, (2) pure adhesive joint and (3) 4 kinds of hybrid joints. The surface-based cohesive behavior was used for creation of the adhesive layer, whereas the rivets were modelled by connector type fasteners, which simplify complexity of the numerical model. The use of connectors allowed for effort assessment taking into account damage in both types of connections. Application of connector elements can be useful for larger structures modelling, e.g. aircraft fuselage, where the number of mechanical joints is significant and complex load conditions occur.

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Authors and Affiliations

T. Sadowski
M. Nowicki
P. Golewski
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Abstract

In hot forging process, tool life is an important factor which influences the economy of production. Wear mechanisms in these processes are dependent on each other, so modeling of them is a difficult problem. The present research is focused on development of a hybrid tool wear model for hot forging processes and evaluation of adding adhesive mechanism component to this model. Although adhesive wear is dominant in cases, in which sliding distances are large, there is a group of hot forging processes, in which adhesion is an important factor in specific tool parts. In the paper, a proposed hybrid tool wear model has been described and various adhesive wear models have been reviewed. The feasible model has been chosen, adapted and implemented. It has been shown that adding adhesive wear model increases predictive capabilities of the global hybrid tool wear model as far as characteristic hot forging processes is considered.

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Authors and Affiliations

M. Wilkus
Ł. Rauch
D. Szeliga
M. Pietrzyk
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Abstract

Nitrogen-doped DLC (diamond-like carbon) coatings were produced on 316L nitrided austenitic steel in direct current and pulsed glow discharge conditions. The chemical composition, surface topography, hardness and corrosion resistance of the obtained carbon coatings were examined. The coatings varied in surface morphology, roughness and hardness. Direct current glow discharge made it possible to produce a coating characterized by lower hardness, greater thickness and higher nitrogen content. The coating featured improved corrosion resistance and adhesion compared to coatings produced in the pulsed process.

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Authors and Affiliations

T. Borowski
ORCID: ORCID
M. Spychalski
ORCID: ORCID
K. Rożniatowski
ORCID: ORCID
K. Kulikowski
ORCID: ORCID
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Abstract

Both the steel loss to scale and the scale adhesion are very important parameters of the heating process. High values of steel loss (large thickness of the scale layer) reduce the heat exchange intensity in the furnace chamber, which results in higher energy consumption. A low adhesion value adversely affects the operation of heating furnaces, while too high value causes the scale to roll into a steel product and deteriorate its purity and quality.
The paper presents the research methodology and the results of measurements of steel loss and scale adhesion. The effect of the excess air combustion ratio values on loss of steel and scale adhesion for constant furnace efficiency is discussed. This influence was described by mathematical dependencies. The tests were carried out for traditional technology and rational technology, enabling the reduction of steel losses to scale and energy consumption.
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Authors and Affiliations

T. Wyleciał
1
ORCID: ORCID
J. Boryca
1
ORCID: ORCID
D. Urbaniak
2
ORCID: ORCID

  1. Czestochowa University of Technology, Faculty of Production Engineering and Materials Technology, Department of Production Management,19 Armii Krajowej Av., 42-201 Czestochowa, Poland
  2. Czestochowa University of Technology, Faculty of Mechanical Engineering and Computer Science, Department of Thermal Machinery, 19 Armii Krajowej Av., 42-201 Czestochowa, Poland
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Abstract

In this study, the results of experiment research on building mortars based on dry mixtures with the use of granite dust are given. It also shows the possibilities of their industrial release. In the conditions of energy resources shortage, gradual exhaustion of natural raw materials, aggravation of environmental problems, an important direction in the production of building mixtures is the development of mixes with waste materials from various industries. In particular, granite dust, which simultaneously allows to rationally use natural mineral material and solve environmental problems. Based on the obtained data, experimental and statistical models of physical and mechanical properties of fresh and hardened mortar are constructed and ways of optimizing their compositions and improving the properties of mortars are analyzed. It is established that the use of granite dust and some additives provides high standardized parameters for mortar mixture and bricklaying process, including plasticity, compressive strength and others at the low level of cement consumption. Fresh mortar mixtures have a prolonged slump retention.

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Authors and Affiliations

Grzegorz Prokopski
ORCID: ORCID
Vitaliy Marchuk
ORCID: ORCID
Andriy Huts
ORCID: ORCID
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Abstract

To explore the basic principles of hierarchical materials designed from nanoscale and up, we have been studying the mechanics of robust and releasable adhesion nanostructures of gecko [1]. On the question of robust adhesion, we have introduced a fractal-like hierarchical hair model to show that structural hierarchy allows the work of adhesion to be exponentially enhanced as the level of structural hierarchy is increased. We show that the nanometer length scale plays an essential role in the bottom-up design and, baring fracture of hairs themselves, a hierarchical hair system can be designed from nanoscale and up to achieve flaw tolerant adhesion at any length scales. For releasable adhesion, we show that elastic anisotropy leads to orientation-dependent adhesion strength. Finite element calculations revealed that a strongly anisotropic attachment pad in contact with a rigid substrate exhibits essentially two levels of adhesion strength depending on the direction of pulling.

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Authors and Affiliations

H. Yao
H. Gao
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Abstract

In this paper study results of selected production methods for agricultural biogas are shown and technical and technological aspects of these methods are described for monosubstrate bioreactors. Based on the available literature, modelling of mixing in bioreactors using computational fluid dynamics (CFD) was is demonstrated. As part of the research, the numerical simulation method was used with a tool that contains CFD codes. The model k-ε is used to simulate the mean flow characteristics under turbulent flow conditions. This is a two-equation model that gives a general description of turbulence. The work presents the results of numerical studies that make it possible to understand the characteristics of fluid flow in the adhesive bed used for the production of agricultural biogas. The tests showed that in the core of the adhesive bed there is a flow of 0.19 m∙s –1, while in the outer part of the bed there is a flow in the range 0.01–0.02 m∙s –1. Taking into account the substrate inflow of 0.17 m∙s –1 (in the upper part of the fermentor), it was observed that the Klinkenberg effect for autocyclic movement (from bottom to top) takes place. The novelty in the article is the observation of the dominant flow in the core of the bed and the autocyclic flow in the opposite direction in the peripheral areas of the adhesive bed.
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Authors and Affiliations

Grzegorz Wałowski
1
ORCID: ORCID

  1. Institute of Technology and Life Sciences – National Research Institute, Falenty, al. Hrabska 3, 05-090 Raszyn, Poland
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Abstract

In the present investigation Ni particles were added in varying weight fractions (0.5, 1.0 and 1.5%) to AA6061 alloy during stir casting. To prepare Al-Ni intermetallic reinforced Aluminium Metal Matrix Composites (Al MMCs), as-cast samples were subjected to T6 treatment (Solutionization at 550°C followed by ageing at 2,4,6,8 and 10 hours). Base alloy was also subjected to T6 treatment for comparison purpose. Hardness of the samples were obtained using Vickers hardness test. Samples in the peak aged (T6) condition were subjected to metallographic examination. Influence of Ni particles on the hardness and grain refinement was investigated. X-ray Diffraction analysis of the Ni added samples revealed the presence of Al-Ni intermetallic phase formation in the peak aged (T6) Condition. Scanning Electron Microscope – Energy Dispersive X-Ray Spectroscopy analysis of composites in the peak aged (T6) condition were carried out to study the formation of the Al-Ni intermetallic phase. Effect of Al-Ni intermetallic phase on wear and friction behavior of the composite samples were studied and compared with that of the base alloy in the peak aged (T6) condition.
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Authors and Affiliations

J. Abuthakir
1
ORCID: ORCID
R. Subramanian
1
ORCID: ORCID
K. Somasundara Vinoth
2
ORCID: ORCID
G. Venkatesh
1
ORCID: ORCID
G. Suganya Priyadharshini
3
ORCID: ORCID
K. Krishnakumar
1
ORCID: ORCID

  1. Metallurgical Engineering, PSG College of Technology, India-641004
  2. Production Engineering, PSG College of Technology, India-641004
  3. Mechanical Engineering, Coimbatore Institute of Technology, India-641004
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Abstract

The article concerns modern, flexible adhesive joints, which might be used in timber construction. The article discusses the test results carried out for timber elements joints using polymeric adhesives produced by Sika®. The scope of the tests includes the analysis of strength criteria, tests of polymer adhesion to the timber with a pull-off method, tests of polymer layer shearing between timber elements as well as examination of bending of timber elements joined with polymer. The conclusions indicate the types of these polymers which are recommended for the creation of polymeric joints of timber-polymeric type in timber constructions.

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Authors and Affiliations

Klaudia Śliwa-Wieczorek
Bogusław Zając
Tomasz Kozik
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Abstract

The article discusses results of pull-off adhesion strength tests on poly-p- phenylene benzobisoxazole (PBO) mesh bonded to fir timber beams using epoxy resin. The tests were performed in accordance with the PN-EN 1542 standard. Timber elements reinforced with PBO fibres were subjected to pull-off tests to measure the adhesive strength of the mesh to the beams.The factors occurring during the test were also characterized, which may affect its results such as the method of application of the tearing force, selection of epoxy glue, surface preparation of the tested elements, occurrence of material defects in the wood and types of substrate destruction.The experimental data show that failure of the timber layer was not observed in all the specimens tested.

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Authors and Affiliations

P.K. Sokołowski
P.G. Kossakowski
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Abstract

The problem of optimal design of symmetrical double-lap adhesive joint is considered. It is assumed that the main plate has constant thickness, while the thickness of the doublers can vary along the joint length. The optimization problem consists in finding optimal length of the joint and an optimal cross-section of the doublers, which provide minimum structural mass at given strength constraints. The classical Goland-Reissner model was used to describe the joint stress state. A corresponding system of differential equations with variable coefficients was solved using the finite difference method. Genetic optimization algorithm was used for numerical solution of the optimization problem. In this case, Fourier series were used to describe doubler thickness variation along the joint length. This solution ensures smoothness of the desired function. Two model problems were solved. It is shown that the length and optimal shape of the doubler depend on the design load.
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Bibliography

[1] L.F.M. da Silva, P.J.C. das Neves, R.D. Adams, and J.K. Spelt. Analytical models of adhesively bonded joints. Part I: Literature survey. International Journal of Adhesion and Adhesives, 29(3):319–330, 2009. doi: 10.1016/j.ijadhadh.2008.06.005.
[2] E.H. Wong and J. Liu. Interface and interconnection stresses in electronic assemblies – A critical review of analytical solutions. Microelectronics Reliability, 79:206–220, 2017. doi: 10.1016/j.microrel.2017.03.010.
[3] S. Budhe, M.D. Banea, S. de Barros, and L.F.M. da Silva. An updated review of adhesively bonded joints in composite materials. International Journal of Adhesion and Adhesives, 72:30–42, 2017. doi: 10.1016/j.ijadhadh.2016.10.010.
[4] K.P. Barakhov and I.M. Taranenko. Influence of joint edge shape on stress distribution in adhesive film. In: M. Nechyporuk, V. Pavlikov, D. Kritskiy (eds) Integrated Computer Technologies in Mechanical Engineering – 2021. ICTM 2021. Lecture Notes in Networks and Systems, 367:123–132, Springer, Cham, 2022. doi: 10.1007/978-3-030-94259-5_12.
[5] H. Lee, S. Seon, S. Park, R. Walallawita, and K. Lee. Effect of the geometric shapes of repair patches on bonding strength. The Journal of Adhesion, 97(3):1–18, 2019. doi: 10.1080/00218464.2019.1649660.
[6] F. Ramezani, M.R. Ayatollahi, A. Akhavan-Safar, and L.F.M. da Silva. A comprehensive experimental study on bi-adhesive single lap joints using DIC technique. International Journal of Adhesion and Adhesives, 102:102674, 2020. doi: 10.1016/j.ijadhadh.2020.102674.
[7] Ya.S. Karpov. Jointing of high-loaded composite structural components. Part 2. Modeling of stress-strain state. Strength of Materials, 38(5):481–491, 2006. doi: 10.1007/s11223-006-0067-9.
[8] J. Kupski and S. Teixeira de Freitas. Design of adhesively bonded lap joints with laminated CFRP adherends: Review, challenges and new opportunities for aerospace structures. Composite Structures, 268:113923, 2021. doi: 10.1016/j.compstruct.2021.113923.
[9] S. Amidi and J. Wang. An analytical model for interfacial stresses in double-lap bonded joints. The Journal of Adhesion, 95(11):1031–1055, 2018. doi: 10.1080/00218464.2018.1464917.
[10] H. Kumazawa and T. Kasahara. Analytical investigation of thermal and mechanical load effects on stress distribution in adhesive layer of double-lap metal-composite bonded joints. Advanced Composite Materials, 28(4):425–444, 2019. doi: 10.1080/09243046.2019.1575028.
[11] S. Kurennov and N. Smetankina. Stress-strain state of a double lap joint of circular form. Axisymmetric model. In: M. Nechyporuk, V. Pavlikov D. Kritskiy (eds) Integrated Computer Technologies in Mechanical Engineering – 2021. ICTM 2021. Lecture Notes in Networks and Systems, 367:36–46, Springer, Cham, 2022. doi: 10.1007/978-3-030-94259-5_4.
[12] S. E. Stapleton, B. Stier, S. Jones, A. Bergan, I. Kaleel, M. Petrolo, E. Carrera, and B.A. Bednarcyk. A critical assessment of design tools for stress analysis of adhesively bonded double lap joints. Mechanics of Advanced Materials and Structures, 28(8):791–811, 2019. doi: 10.1080/15376494.2019.1600768.
[13] R.H. Kaye and M. Heller. Through-thickness shape optimisation of bonded repairs and lap-joints. I nternational Journal of Adhesion and Adhesives, 22(1):7–21, 2002. doi: 10.1016/s0143-7496(01)00029-x.
[14] S. Kurennov, K. Barakhov, I. Taranenko, and V. Stepanenko. A genetic algorithm of optimal design of beam at restricted sagging. Radioelectronic and Computer Systems, 1:83–91, 2022. doi: 10.32620/reks.2022.1.06.
[15] V.S. Symonov, I.S. Karpov, and J. Juračka. Optimization of a panelled smooth composite shell with a closed cross-sectional contour by using a genetic algorithm. Mechanics of Composite Materials, 49(5):563–570, 2013. doi: 10.1007/s11029-013-9372-0.
[16] N.S. Kulkarni, V.K. Tripathi. Variable thickness approach for finding minimum laminate thickness and investigating effect of different design variables on its performance. Archive of Mechanical Engineering, 65(4):527–551, 2018. doi: 10.24425/ame.2018.125441.
[17] H. Ejaz, A. Mubashar, I.A. Ashcroft, E. Uddin, and M. Khan. Topology optimisation of adhesive joints using non-parametric methods. International Journal of Adhesion and Adhesives, 81:1–10, 2018. doi: 10.1016/j.ijadhadh.2017.11.003.
[18] H.L. Groth and P. Nordlund. Shape optimization of bonded joints. International Journal of Adhesion and Adhesives, 11(4):204–212, 1991. doi: 10.1016/0143-7496(91)90002-y.
[19] R.Q. Rodríguez, R. Picelli, P. Sollero, and R. Pavanello. Structural shape optimization of bonded joints using the ESO method and a honeycomb-like mesh. J ournal of Adhesion Science and Technology, 28(14-15):1451–1466, 2014. doi: 10.1080/01694243.2012.698112.
[20] E.G. Arhore, M. Yasaee, and I. Dayyani. Comparison of GA and topology optimization of adherend for adhesively bonded metal composite joints. International Journal of Solids and Structures, 226-227:111078, 2021. doi: 10.1016/j.ijsolstr.2021.111078.
[21] S. Kumar, and de A. de Tejada Alvarez. Modeling of geometrically graded multi-material single-lap joints. 56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. doi: 10.2514/6.2015-1885.
[22] S.S. Kurennov: Refined mathematical model of the stress state of adhesive lap joint: experimental determination of the adhesive layer strength criterion. Strength of Materials, 52:779–789, 2020. doi: 10.1007/s11223-020-00231-5.
[23] P. Zou, J. Bricker, and W. Uijttewaal. Optimization of submerged floating tunnel cross section based on parametric Bézier curves and hybrid backpropagation – genetic algorithm. Marine Structures, 74:102807, 2020. doi: 10.1016/j.marstruc.2020.102807.
[24] O. Coskun and H.S.Turkmen. Multi-objective optimization of variable stiffness laminated plates modeled using Bézier curves. Composite Structures, 279:114814, 2022. doi: 10.1016/j.compstruct.2021.114814.
[25] S. Kumar and P.C. Pandey. Behaviour of bi-adhesive joints. Journal of Adhesion Science and Technology, 24(7):1251–1281, 2010. doi: 10.1163/016942409x12561252291982.
[26] Ö. Öz and H. Özer. On the von Mises elastic stress evaluations in the bi-adhesive single-lap joint: a numerical and analytical study. Journal of Adhesion Science and Technology, 28(21):2133–2153, 2014. doi: 10.1080/01694243.2014.948110.
[27] E. Selahi. Elasticity solution of adhesive tubular joints in laminated composites with axial symmetry. Archive of Mechanical Engineering, 65(3):441–456, 2018. doi: 10.24425/124491.
[28] K. Barakhov, D. Dvoretska, and O. Poliakov. One-dimensional axisymmetric model of the stress state of the adhesive joint. In: M. Nechyporuk, V. Pavlikov, D. Kritskiy (eds) I ntegrated Computer Technologies in Mechanical Engineering – 2020. ICTM 2020. Lecture Notes in Networks and Systems, 188:310–319, Springer, Cham, 2021. doi: 10.1007/978-3-030-66717-7_26.
[29] S. Kurennov, N. Smetankina, V. Pavlikov, D. Dvoretskaya, V. Radchenko. Mathematical model of the stress state of the antenna radome joint with the load-bearing edging of the skin cutout. In: D.D. Cioboată, (ed.) International Conference on Reliable Systems Engineering (ICoRSE) – 2021. ICoRSE 2021. Lecture Notes in Networks and Systems, 305:287–295, Springer, Cham, 2022. doi: 10.1007/978-3-030-83368-8_28.
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Authors and Affiliations

Sergei Kurennov
1
ORCID: ORCID
Konstantin Barakhov
1
ORCID: ORCID
Olexander Polyakov
1
ORCID: ORCID
Igor Taranenko
1
ORCID: ORCID

  1. National Aerospace University “Kharkiv Aviation Institute”, Kharkiv, Ukraine

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