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Number of results: 13
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Abstract

The author of this article calls into question the suitability of the regulation in the Maritime Code relating to the division of a reward for salvage at sea. According to him, this regulation has been unclear for 30 years. He considers that the transfer of this kind of dispute to general courts may further make it difficultfor the crew ofthe salvaging vessel to obtain a part ofany reward. The division of a reward for salvage within the crew should have more precise definition inasmuch as there is an increasing number ofdisputes on this matter. This view is not reflected in the new Maritime Code; quite the reverse, it regulates this matter in an even more general and enigmatic manner, thus creating huge scopefor legal disputes.
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Authors and Affiliations

Zbigniew Godecki
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Abstract

Presented paper shows the mathematical and numerical approaches for modelling of binary alloy solidification solved by the Finite Element Method (FEM). The phenomenon of shrinkage cavities formation process is included in the numerical model. Multiple macroscopic cavities can be modelled within the single casting volume. Solid, liquid and gaseous phases with different material properties are taken into account during solidification process. Mathematical model uses the differential equation of heat diffusion. Modification of specific heat is used to describe the heat releasing during liquid-solid phase change. Numerical procedure of shrinkage cavities evolution is based on the recognition of non-connected liquid volumes and local shrinkage computation in the each of them. The recognition is done by the selection of sets of interconnected nodes containing liquid phase in the finite element mesh. Original computer program was developed to perform calculation process. Obtained results of temperature and shrinkage cavities distributions are presented and discussed in details.

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Authors and Affiliations

T. Skrzypczak
L. Sowa
E. Węgrzyn-Skrzypczak
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Abstract

The paper describes influence of rare earth metals (REMs) on G20Mn5 cast steel microstructure and mechanical properties. The cerium mixture of the following composition was used to modify cast steel: 49.8% Ce, 21.8% La, 17.1% Nd, 5,5% Pr and 5.35% of REMs. Cast steel was melted in industrial conditions. Two melts of non-modified and modified cast steel were made. Test ingots were subject to heat treatment by hardening (920°C/water) and tempering (720°C/air). Heat treatment processes were also performed in industrial conditions. After cutting flashes off samples of cast steel were collected with purpose to analyze chemical composition, a tensile test and impact toughness tests were conducted and microstructure was subject to observations. Modification with use of mischmetal did not cause significant changes in cast steel tensile strength and yield strength, while higher values were detected for fractures in the Charpy impact test, as they were twice as high as values for the data included in the PN-EN 10213:2008 standard. Observations performed by means of light and scanning microscopy proved occurrence of significant differences in grain dimensions and morphology of non-metallic inclusions. Adding REMs resulted in grain fragmentation and transformed inclusion shapes to rounded ones. Chemical composition analyses indicated that round inclusions in modified cast steel were generally oxysulphides containing cerium and lanthanum. In the paper the author proved positive influence of modification on G20Mn5 cast steel mechanical properties.
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Authors and Affiliations

J. Kasińska
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Abstract

Semiconductive - resistive sensors of toxic and explosive gases were fabricated from nanograins of SnO2 using thick-.lm technology. Sensitivity, selectivityand stabilityof sensors working in di.erent temperature depend on the way the tin dioxide and additives were prepared. A construction also plays an important role. The paper presents an attitude towards the evaluation of transport of electrical charges in semiconductive grain layer of SnO2, when dangerous gases appear in the surrounding atmosphere.

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Authors and Affiliations

B. Licznerski
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Abstract

The article discusses a few fi lm portraits of Tadeusz Kościuszko and his fi ght against the tsar’s Russia.
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Authors and Affiliations

Roman Włodek
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Abstract

The present study aimed to evaluate the efficiency of hypertonic saline solution (HSS) as a novel treatment of acute ruminal lactic acidosis (ARLA) in cattle, focusing on urinary excretion of acids. Twelve cannulated steers were submitted to experimentally induced ARLA by adminis- tering sucrose into the rumen. Twenty hours later, the cattle were randomly divided into two equal groups. The first group was treated with 7.5% HSS (5 mL/kg) over 15 min, and isotonic saline solution (ISS; 20 mL/kg) for the subsequent 165 minutes. The control group was administered ISS instead of HSS. Rumen and urine samples were collected at different times during the experiment from the baseline to 64 h post-induction. The induction caused a medium-to-moderate ruminal acidosis, and a moderate degree of systemic acidosis and dehydration. Steers treated with HSS increased by 50% its glomerular filtration rate (1.61 mL/min) compared to ISS group (1.06 mL/ min; p<0.03). The overall volume of urine excreted by HSS group was higher than that in ISS group (1.62 L vs 0.7 L; p<0.02). This increase in total volume of urine provided by HSS favored a greater excretion of H+ ions in urine, which was 3.39-fold higher in HSS group (64.3*10-7 vs 18.9*10-7 Mol) as well as lactate (241.7 vs 181.8 mMol) and P urinary excretion (3.8 vs 1.1 mMol) that reduced the urine pH (5.3 vs 5.7). Only the HSS group decreased significantly blood total lactic acid concentration (20.3 %) throughout the treatment. A positive relationship was found between the excretion of urinary phosphorus and urinary pH (r2=0.562). The results showed that this novel treatment with HSS enhanced renal excretion of acids and may be recommended as an additional treatment for cattle with lactic acidosis.

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Authors and Affiliations

F.A.M.L. Rodrigues
A.H.H. Minervino
R.A. Barrêto Júnior
L.F. Reis
R.N.F. Ferreira
C.S. Mori
F.L.C. Oliveira
R.S. Sousa
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Abstract

The European rabbit (Oryctolagus cuniculus) is a good model in biomedicine used in research on several human diseases. The reference values of B and T cells and their subpopu- lations are very important to understand how the adaptive immune system is responding to infectious agents. The aim of this study was to determine values of B and T cells and their subpopulations in Polish mixed-breed rabbits, considering seasons of the year and sex. The study was performed on 200 Polish mixed-breed rabbits and the percentage of B and T lymphocytes was measured cytometrically using mouse anti-rabbit antibodies. The study revealed that the season of the year and sex of the animals affected the percentage of B- and T-cells and their subpopulations in peripheral blood. Statistically significant values of CD19+ B-cells in spring and autumn, of T CD5+ cells in spring and winter, of T CD4+ in spring, summer, autumn and winter, of T CD8+ in winter and of T CD25+ in spring were noted. Generally the highest values were found mainly in warm part of the year, while the lowest in colder months. A statistical significance was also observed between males and females – changes were found in T CD4+ and T CD25+ lymphocytes in spring, T CD8+ cells in winter and higher percentage was generally obtained in females than in males. The only exception was the T CD5+ subpopulation in which no differences were observed between the sexes and throughout the year. This is the first paper on adaptive immune system cell values in the European rabbit of domestic breeds.

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Authors and Affiliations

P. Niedźwiedzka-Rystwej
B. Tokarz-Deptuła
J. Abrantes
P.J. Esteves
W. Deptuła
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Abstract

The article presents tests on a new lead-free bronze CuSn4Zn2PS, intended for fittings for contact with drinking water, in which the addition of lead was replaced with sulphur. The subject of the experimental work was the production of semi-finished products from this alloy based on the charge coming entirely from waste generated after machining. A specialized pilot line was used for the tests, and after cleaning, the waste was melted and then were continuously cast in the form of rods and hollow rods. The cleaning efficiency was assessed, and the manufactured semi-finished products were subjected to tests, including the assessment of the chemical and mechanical homogeneity and the structure of the test batch of the semi-finished casting products in terms of the possibility of manufacturing products meeting the requirements of technical specifications. The obtained results, both in terms of a stable chemical composition, homogeneous and reproducible mechanical properties, fully compliant with the specifications for fittings bronzes (CC499K), as well as the lack of faults of the obtained semi-finished products, despite a very large share of waste material, indicate the possibility of using the tested recycling method for the production of semi-products of sulphur bronze, which is an alloy that is relatively difficult to manufacture.
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Bibliography

[1] Directive (EU) 2020/2184 of the European Parliament and of the Council of 16 December 2020 on the quality of water intended for human consumption, Dz.U.L 435/1 of 23.12.2020.
[2] Acceptance of metallic materials used for products in contact with drinking water, 4MS Common Approach Part B “4MS Common Composition List” Retrieved July, 12, 2022 from http://www.umweltbundesamt.de/en/topics/water/drinking-water/distributing-drinking-water/guidelines-evaluation-criteria.
[3] DIN SPEC 2701:2018.
[4] Haake, M., Hansen, A., Leistritz, F. (2019). EP Patent No. EP 3436615. Germany. The German Patent and Trade Mark Office.
[5] PN-EN 1982:2017 Copper and copper alloys - Ingots and castings
[6] Wieland G05, GD1, GS1, SW3 material specification. Retrieved 12, July, 2022 from https://www.wieland.com/en/content/download/.
[7] Marek, W., Kopańska, D., Bieniek, J., Wróbel, D., Stolorz, K., Filipowicz, A., Malec, W., Cwolek, B., Brudny, A., Juszczyk B., Kulasa, J. (2022). PL Patent application No. PL 436188. Poland. The Patent Office of the Republic of Poland.
[8] Cwolek, B., Malec, W., Brudny, A., Kulasa, J., Marek, W., Stolorz, K., Wróbel, D. & Filipowicz, A. (2022). Development of process conditions for the preparation of copper alloys post-production chips for the continuous casting process. Archives of Foundry Engineering. (in publication).
[9] PN-EN 12861:2018-07 Copper and copper alloys – Scrap.
[10] Hansen, A. (2019). Bleifreier rotguss als armaturen-und installationswerkstoff in der trinkwasserinstallation. METALL – Forschung. 73(11), 452-455.

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Authors and Affiliations

W. Malec
1
ORCID: ORCID
B. Cwolek
1
ORCID: ORCID
A. Brudny
1
ORCID: ORCID
B. Juszczyk
1
ORCID: ORCID
J. Kulasa
1
ORCID: ORCID
A. Hury
1
ORCID: ORCID
W. Marek
2
K. Stolorz
2
D. Wróbel
2
A. Filipowicz
2

  1. Łukasiewicz Research Network — Institute of Non-Ferrous Metals, Poland
  2. COGNOR S.A. Oddział OM Szopienice w Katowicach, Poland
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Abstract

A method for the open-cell aluminum foams manufacturing by investment casting was presented. Among mechanical properties, compressive behaviour was investigated. The thermal performance of the fabricated foams used as heat transfer enhancers in the heat accumulator based on phase change material (paraffin) was studied during charging-discharging working cycles in terms of temperature distribution. The influence of the foam on the thermal conductivity of the system was examined, revealing a two-fold increase in comparison to the pure PCM. The proposed castings were subjected to cyclic stresses during PCM’s subsequent contraction and expansion, while any casting defects present in the structure may deteriorate their durability. The manufactured heat transfers enhancers were found suitable for up to several dozen of cycles. The applied solution helped to facilitate the heat transfer resulting in more homogeneous temperature distribution and reduction of the charging period’s duration.
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Bibliography

[1] Bisht, A., Patel, V.K. & Gangil, B. (2019). Future of metal foam materials in automotive industry. In Jitendra K. K., Shantanu B., Vinay K. P. & Vikram K. (Eds.), Automotive Tribology, (pp. 51-63). Springer, Singapore, DOI: 10.1007/978-981-15-0434-1_4.
[2] Almonti, D., Baiocco, G., Mingione, E. & Ucciardello, N. (2020). Evaluation of the effects of the metal foams geometrical features on thermal and fluid-dynamical behavior in forced convection. The International Journal of Advanced Manufacturing Technology. 111(3), 1157-1172. DOI: 10.1007/S00170-020-06092-1.
[3] Sivasankaran, S. & Mallawi, F.O.M. (2021). Numerical study on convective flow boiling of nanoliquid inside a pipe filling with aluminum metal foam by two-phase model. Case Studies in Thermal Engineering. 26, 101095. DOI: 10.1016/J.CSITE.2021.101095.
[4] Anglani, A., Pacella, M. (2021). Binary Gaussian Process classification of quality in the production of aluminum alloys foams with regular open cells. In 14th CIRP Conference on Intelligent Computation in Manufacturing Engineering, 15-17 July 2020 (pp. 307–312). Gulf of Naples, Italy: The International Academy for Production Engineering.
[5] Anglani, A., Pacella, M. (2018). Logistic Regression and Response Surface Design for Statistical Modeling of Investment Casting Process in Metal Foam Production. In 11th CIRP Conference on Intelligent Computation in Manufacturing Engineering, 19-21 July 2017 (pp. 504–509). Gulf of Naples, Italy: The International Academy for Production Engineering.
[6] Kryca, J., Iwaniszyn, M., Piątek, M., Jodłowski, P.J., Jędrzejczyk, R., Pędrys, R., Wróbel, A., Łojewska, J., Kołodziej, A. (2016). Structured foam reactor with CuSSZ-13 catalyst for SCR of NOx with ammonia. Topics in Catalysis. 59(10), 887-894. DOI: 10.1007/S11244-016-0564-4.
[7] Alamdari, A. (2015). Performance assessment of packed bed reactor and catalytic membrane reactor for steam reforming of methane through metal foam catalyst support. Journal of Natural Gas Science and Engineering. 27, 934-944. DOI: 10.1016/J.JNGSE.2015.09.037.
[8] Vilniškis, T., Januševičius, T. & Baltrėnas, P. (2020). Case study: Evaluation of noise reduction in frequencies and sound reduction index of construction with variable noise isolation. Noise Control Engineering Journal. 68(3), 199-208. DOI: 10.3397/1/376817.
[9] Hua, L., Sun, H. & Gu Jiangsu, J. (2016). Foam metal metamaterial panel for mechanical waves isolation. Conference: SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring. DOI: 10.1117/12.2219470.
[10] Wang, Y., Jiang, S., Wu, Z., Shao, H., Wang, K. & Wang, L. (2018). Study on the inhibition influence on gas explosions by metal foam based on its density and coal dust. Journal of Loss Prevention in the Process Industries. 56, 451-457. DOI: 10.1016/J.JLP.2018.09.009.
[11] Marx, J. & Rabiei, A. (2017). Overview of composite metal foams and their properties and performance. Advanced Engineering Materials. 19(11), 1600776. DOI: 10.1002/ADEM.201600776.
[12] Tong, X., Shi, Z., Xu, L., Lin, J., Zhang, D., Wang, K., Li, Y., Wen, C. (2020). Degradation behavior, cytotoxicity, hemolysis, and antibacterial properties of electro-deposited Zn–Cu metal foams as potential biodegradable bone implants. Acta Biomaterialia. 102, 481-492. DOI: 10.1016/J.ACTBIO.2019.11.031
[13] Banhart, J. (2001). Manufacture, characterisation and application of cellular metals and metal foams. Progress in Materials Science. 46, 559-632. DOI: 10.1016/S0079-6425(00)00002-5.
[14] Schüler, P., Fischer, S.F., Bührig-Polaczek, A. & Fleck, C. (2013). Deformation and failure behaviour of open cell Al foams under quasistatic and impact loading. Materials Science and Engineering: A, 587, 250-261. DOI: 10.1016/J.MSEA.2013.08.030.
[15] Schüler, P., Frank, R., Uebel, D., Fischer, S.F., Bührig-Polaczek, A. & Fleck, C. (2016). Influence of heat treatments on the microstructure and mechanical behaviour of open cell AlSi7Mg0.3 foams on different lengthscales. Acta Materialia. 109, 32-45. DOI: 10.1016/J.ACTAMAT.2016.02.041.
[16] Luksch, J., Bleistein, T., Koenig, K., Adrien, J., Maire, E. & Jung, A. (2021). Microstructural damage behaviour of Al foams. Acta Materialia. 208, 116739. DOI: 10.1016/J.ACTAMAT.2021.116739.
[17] Sathaiah, S., Dubey, R., Pandey, A., Gorhe, N.R., Joshi, T. C., Chilla, V., Muchhala, D., Mondal, D.P. (2021). Effect of spherical and cubical space holders on the microstructural characteristics and its consequences on mechanical and thermal properties of open-cell aluminum foam. Materials Chemistry and Physics. 273, 125115. DOI: 10.1016/j.matchemphys.2021.125115
[18] Qu, Z. (2018). Heat transfer enhancement technique of pcms and its lattice Boltzmann modeling. In Mohsen Sheikholeslami Kandelousi (Eds.), Thermal Energy Battery with Nano-enhanced PCM. IntechOpen Limited, London, UK. DOI: 10.5772/INTECHOPEN.80574
[19] Tian, Y. & Zhao, C.Y. (2011). A numerical investigation of heat transfer in phase change materials (PCMs) embedded in porous metals. Energy. 36, 5539-5546. DOI: 10.1016/j.energy.2011.07.019.
[20] Novak, N., Vesenjak, M., Duarte, I., Tanaka, S., Hokamoto, K., Krstulović-Opara, L., Guo, B., Chen, P., Ren, Z. (2019). Compressive behaviour of closed-cell aluminium foam at different strain rates. Materials. 12(24), 4108. DOI: 10.3390/MA12244108.
[21] Naplocha, K., Dmitruk, A., Mayer, P. & Kaczmar, J.W. (2019). Design of honeycomb structures produced by investment casting. Archives of Foundry Engineering. 19(4), 76-80. DOI: 10.24425/AFE.2019.129633.
[22] Zhou, J. & Soboyejo, W.O. (2004). Compression–compression fatigue of open cell aluminum foams: macro-/micro- mechanisms and the effects of heat treatment. Materials Science and Engineering A. 369(1-2), 23-35. DOI: 10.1016/J.MSEA.2003.08.009.
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[25] Naplocha, K., Koniuszewska, A., Lichota, J. & Kaczmar, J. W. (2016). Enhancement of heat transfer in PCM by vellular Zn-Al structure. Archives of Foundry Engineering. 16(4), 91-94. DOI: 10.1515/AFE-2016-0090

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Authors and Affiliations

A. Dmitruk
1
ORCID: ORCID
H. Kapłon
1
ORCID: ORCID
K. Naplocha
1
ORCID: ORCID

  1. Department of Lightweight Elements Engineering, Foundry and Automation, Faculty of Mechanical Engineering, Wrocław University of Science and Technology, Poland
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Abstract

The paper presents an analysis of a selected grade of high silicon cast iron intended for work in corrosive and abrasive conditions. The text describes its microstructure taking into account the process of crystallization, TDA analysis, EDS, XRD and the chemical composition analysis. In order to determine the phase composition, X-ray diffraction tests were carried out. The tests were executed on a Panalytical X'Pert PRO X-ray diffractometer with filtration of radiation from a lamp with copper anode and PIXcel 3D detector on the deflected beam axis. Completed tests allowed to describe the microstructure with detailed consideration of intermetallic phases present in the alloy. Results of the analysis of the examined alloy clearly show that we deal with intermetallic phases of Fe3Si, Fe5Si3 types, as well as silicon ferrite and crystals of silicon. In the examined alloy, we observed the phenomenon of segregation of carbon, which, as a result of this process, enriches the surface of silicon crystals, not creating a compound with it. Moreover, the paper demonstrates capability for crystallization of spheroidal graphite in the examined alloy despite lack of elements that contribute to balling in the charge materials.

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Authors and Affiliations

M. Stawarz
ORCID: ORCID
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Abstract

Surface coating technology, as the main technology to improve the fatigue life of mechanical systems, has been well applied in mechanical equipment. The present study aimed to explore low-cost surface coating preparation technology using inexpensive rice husk as the research object, and the pyrolysis process behavior of rice husk was analyzed. The Ni60/SiO 2 coating was prepared on the surface of the 45# steel substrate using the pyrolysis product SiO 2 fiber as the reinforcing phase and supersonic plasma-spraying equipment. The results showed no defects such as cracks, pores, and inclusions in the prepared coating. The nanohardness of the Ni60/SiO 2 coating reached 6506 μN, and the average friction coefficient reached 0.42. In the friction-and-wear experiment, the Ni60/SiO 2 coating was manifested as an abrasive wear mechanism.
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Authors and Affiliations

Chunxue Wei
1
Hongbing Li
1

  1. Henan Light Industry Vocational College, Zhengzhou, 450002, P.R. China
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Abstract

Trematomus newnesi (Nototheniidae), a bentho-pelagic fish, caught off Adélie Land (eastern Antarctic) was examined for the presence of internal parasitic worms. These fishes were infected with 11 species and larval forms of parasites: Digenea (Macvicaria pennelli, Neolebouria terranovaensis, Genolinea bowersi, and Elytrophalloides oatesi), larval Cestoda (two forms of tetraphyllidean metacestodes, bilocular form and trilocular form, and diphyllobothriid plerocercoids), Acanthocephala (Metacanthocephalus campbelli, M. johnstoni) and larval Nematoda (Contracaecum osculatum, C. radiatum). Larval cestodes were the dominant parasites, whereas acanthocephalans were relatively rare. Five species and larval forms were recorded also in fish caught in the Davis Sea. A check list of parasites of T. newnesi recorded in the eastern- and western Antarctic comprises 21 species and larval forms. Probably, T. newnesi plays an important role in life cycles of parasitic worms in the Antarctic.

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Authors and Affiliations

Zdzisław Laskowski
Anna Rocka
Krzysztof Zdzitowiecki
Catherine Ozouf-Costaz
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Abstract

The Cannae Battlefield (216 BC), a pivotal engagement during the Second Punic War, led to the destruction of one of the largest consular armies ever raised by the Republic. Historians have for centuries paid the utmost attention to unitby- unit dispositions and tactical maneuvers without studying the local geology and particularly the geomorphology of the battle site. A brief traverse over the battle site, adjacent to the museum in 2004, led to a hidden defile, heretofore not mentioned in the literature, one which may have helped turn the tide for the Carthaginians, and offering prospect of further geoarchaeological investigation.
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Authors and Affiliations

William C. Mahaney
1

  1. Quaternary Surveys, 26 Thornhill Ave., Thornhill, Ontario, Canada, L4J1J4, Department of Geography, York University, 4700 Keele St. N. York, Ontario, Canada

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