Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 25
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Porosity is one of the major defects in aluminum castings, which results is a decrease of a mechanical properties. Porosity in aluminum alloys is caused by solidification shrinkage and gas segregation. The final amount of porosity in aluminium castings is mostly influenced by several factors, as amount of hydrogen in molten aluminium alloy, cooling rate, melt temperature, mold material, or solidification interval. This article deals with effect of chemical composition on porosity in Al-Si aluminum alloys. For experiment was used Pure aluminum and four alloys: AlSi6Cu4, AlSi7Mg0, 3, AlSi9Cu1, AlSi10MgCu1.

Go to article

Authors and Affiliations

L. Kucharčík
A. Sládek
M. Brůna
Download PDF Download RIS Download Bibtex

Abstract

Physical analysis of the 15-cm top layer of the Rzuno lake bottom sediments showed that their properties changed adequate by depth. They changed from granular structure, in the lakes shallow parts, to amorphic structure, in the lakes deeper parts, from light color to almost black and from loose to gelatinous consistence. Chemical investigation of this lake bottoms sediments showed that their main components is silica (more than 50% of dry matter of sediments), therefore these bottom sediments were classified as silicate sediments. Organic matter was another essential component of these sediments. The content of organic matter increased adequate by depth from 7% to 36%. The investigated sediments exhibited small contents of nitrogen (about 0.6%), with predominance of organic nitrogen. They make up are characterized by small phosphorus contents (about 0.06%), with similar amount of inorganic and organic phosphorus. The content of metals (Ca, Mg, Fe, Al, Mn) was also small in the investigated sediments. Correlation analysis showed that iron ions precipitate phosphate phosphorus from water and accumulate it in sediments. The material deposited in bottom sediments of Rzuno lake in mainly of an autochthonous origin. The chemical composition of bottom sediments of Rzuno lake, as well as its comparison with other lakes, show that this lake is moderately eutrophic.
Go to article

Authors and Affiliations

Jan Trojanowski
Janusz Bruski
Download PDF Download RIS Download Bibtex

Abstract

Wonji Shoa Sugar Estate (WSSE), located in the flood plain of the Awash River (Ethiopia), has been under long-term (>60 years) irrigation, industrial activities and agro-chemical usage. In this study, the hydrochemical properties of ground-water bodies available at WSSE have been characterized for quality compositions. Water samples were collected from groundwater monitoring piezometers distributed in the sugarcane plantation and then analysed for physico-chemical quality parameters (pH, EC,major cations and anions) following standard procedures. Other chemical indices (e.g., total dissolved solids (TDS),total hardness(TH),magnesium absorption ratio(MAR), base exchange (r1), meteoric genesis(r2)) were de-rived from the measured water quality parameters. The compositional variability and groundwater classification has been presented using the Box and Piper plots. The potential sources of minerals were suggested for each of the considered water sources based on their quality characteristics. Both trilinear Piper plot and meteoric genesis index revealed that groundwaterof the area is shallow meteoric water percolation type with a changing of hydrochemical facies and mixing trend. Ground-water of the area, is group 1 (Ca-Mg-HCO3) type, with no dominant cations and HCO3 are the dominant anions. Overall, the study result elucidates that the chemical composition of GW of the area showed spatial variability depending upon the variations in hydrochemical inputs from natural processes and/or anthropogenic activities within the region. The local an-thropogenic processes could be discharges from sugar factory, domestic sewage and agricultural activities.

Go to article

Authors and Affiliations

Megersa Olumana Dinka
Download PDF Download RIS Download Bibtex

Abstract

Physical and chemical properties of Arctic soils and especially the properties of surface horizons of the soils are very important because they are responsible for the rate and character of plant colonization, development of vegetation cover, and influence the rate and depth of thawing of soils and development of active layer of permafrost during summer. The main aim of the present study is to determine and explain the spatial diversity of selected physical and chemical properties of surface horizons of Arctic soils from the non-glaciated Fuglebekken catchment located in the Hornsund area (SW Spitsbergen) by means of geostatistical approach. Results indicate that soil surface horizons in the Fuglebekken catchment are characterized by highly variable physical and chemical properties due to a heterogeneous parent material (marine sediments, moraine, rock debris), tundra vegetation types, and non-uniform influence of seabirds. Soils experiencing the strongest influence of seabird guano have a lower pH than other soils. Soils developed on the lateral moraine of the Hansbreen glacier have the highest pH due to the presence of carbonates in the parent material and a lack or presence of a poorly developed and discontinuous A horizon. The soil surface horizons along the coast of the Hornsund exhibit the highest content of the sand fraction and SiO2. The surface of soils occurring at the foot of the slope of Ariekammen Ridge is characterized by the highest content of silt and clay fractions as well as Al2O3, Fe2O3, and K2O. Soils in the central part of the Fuglebekken catchment are depleted in CaO, MgO, and Na2O in comparison with soils in the other sampling sites, which indicates the highest rate of leaching in this part of the catchment.
Go to article

Authors and Affiliations

Wojciech Szymański
Janusz Siwek
Joanna Waścińska
Bronisław Wojtuń
Download PDF Download RIS Download Bibtex

Abstract

The cenospheres are formed during the mineral transformation stage in coal combustion. Their content in fly ashes from the combustion of different types of coals varies over a rather wide range from 0.01 to 35.6 wt.%. The cenospheres has three main elements, silicon, aluminium and iron, the oxides of which account for about 89% of the material. Mineralogical analysis using XRD shows that as-received cenospheres mainly contain mullite and quartz as main mineralogical phases. The size of cenospheres varies between 5 and 500 [...], as the most common dimension is 20-300 [...]. The cenospheres are characterized by a low bulk density (0.2-0.8 g/cm3) and can be easily separated by gravitational methods in the form of a concentrate in aqueous media or collected from a water surface of lagoons intended for storage of ash and slag waste. The unique properties of these hollow microspheres make them amenable for wide applications. For example the cenospheres can be used to produce various lightweight construction products, including lightweight cements and aggregates in lightweight concrete.

Go to article

Authors and Affiliations

Elżbieta Haustein
Bernard Quant
Download PDF Download RIS Download Bibtex

Abstract

Changes in the amount of basic nitrogen fractions (total, protein and non-protein nitrogen) were studied in an annual cycle. Significant seasonal changes were noted, minima occurring in Antarctic winter and maxima during spring-summer season. These changes are due mainly to high fluctuations of water content in krill in the annual cycle.

Go to article

Authors and Affiliations

Edward Kołakowski
Download PDF Download RIS Download Bibtex

Abstract

The aim of the studies was to evaluate the influence of sowing rate, foliar fertilization (Basfoliar fertilizer 6-12-6) and chemical composition on the mechanical properties of narrow- leaved lupine seeds of cultivars Bojar and Regent. Single seeds were burdened in the direction perpendicular to the parting plane of cotyledons with constant speed 10 mm∙min-1. The crop year and cultivar have significantly differentiated the value of all the analyzed strength parameters of narrow-leaved lupine seeds. The seeds of cultivar Bojar had significantly higher values of all the strength parameters. The designated strength parameters of lupine seeds were negatively correlated with ash content, fiber and protein except for the destructive force. They were also positively correlated with the fat content.
Go to article

Authors and Affiliations

Piotr Kuźniar
Wacław Jarecki
Stanisław Sosnowski
Dorota Bobrecka-Jamro
Natalia Matłok
Dagmara Migut
Download PDF Download RIS Download Bibtex

Abstract

The cement production process is associated with the emission of dust. These are mainly CKD (cement kiln dust) and BPD (by-pass dust), classified as wastes from group 10 – Wastes from thermal processes, subgroups 10 and 13 – wastes from manufacture of cement, lime and plaster and articles and products made from them. Cement kiln dust is a waste of variable composition and properties, which makes it a difficult material to recover. The main directions of recovery presented in the world literature indicate the use of dust from cement kilns in cement, mortar and concrete production, the production of bricks and in order to improve soil quality and wastewater treatment. Factors affecting chemical and phase compositions of dust from cement kilns are the reason why each waste should be analyzed individually. The paper presents the results of the analysis of the cement kiln dust after dedusting cement kilns and two bypass dusts. Analysis of the chemical composition has shown significant concentrations of chlorine, potassium and calcium in all wastes. The content of: Si, S, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Zr, Pb, and Bi has also been confirmed. The analyzed dusts were characterized by the presence of carbonates (calcite, dolomite, and arcanite), quartz, alite, belite, sylvine, anhydrite, and portlandite in their phase composition. The leachates which were characterized by an alkaline reaction. In terms of leachability, high concentrations of chlorine ions in the analyzed dust leachates were confirmed, which significantly limits their use.

Go to article

Authors and Affiliations

Alicja Uliasz-Bocheńczyk
Download PDF Download RIS Download Bibtex

Abstract

Blast furnace and cupola furnace are furnace aggregates used for pig iron and cast iron production. Both furnace aggregates work on very similar principles: they use coke as the fuel, charge goes from the top to down, the gases flow against it, etc. Their construction is very similar (cupola furnace is usually much smaller) and the structures of pig iron and cast iron are very similar too. Small differences between cast iron and pig iron are only in carbon and silicon content. The slags from blast furnace and cupola furnace are very similar in chemical composition, but blast furnace slag has a very widespread use in civil engineering, primarily in road construction, concrete and cement production, and in other industries, but the cupola furnace slag utilization is minimal. The contribution analyzes identical and different properties of both kinds of slags, and attempts to explain the differences in their uses. They are compared by the contribution of the blast furnace slag cooled in water and on air, and cupola furnace slag cooled on air and granulated in water. Their chemical composition, basicity, hydraulicity, melting temperature and surface were compared to explain the differences in their utilization.

Go to article

Authors and Affiliations

A. Pribulová
P. Futáš
J. Petrík
M. Pokusová
M. Brzeziński
J. Jakubski
Download PDF Download RIS Download Bibtex

Abstract

In order to help develop a better understanding of relevant catchment processes, this paper presents the changes in physico-chemical features of the Wieprz River water during the spring snowmelt flood of 2006. The obtained results showed that the groundwater sampled from the springs and the water sampled from the river had a similar and quite stable composition of the basic physicochemical features in the period of solely groundwater feeding (the river is fed only with the water coming from underground sources). The physico-chemical composition of river water during snowmelt depended on the contribution of surface runoff in total outflow and the flood phase. The correlation coefficients between the discharge in the Wieprz River and the concentrations in the studied indices were significantly negative: pH, SEC, HCO3, Ca, Mg, Na, Sr, SiO2, Cl, SO4, F. Significantly positive correlations associated with an increase in discharge were observed in the case of: K, NO3, NO2, total organic carbon, chemical oxygen demand and biochemical oxygen demand. Step and bidirectional responses were noted during the snowmelt flood in the case of the content of NH4 and PO4.

Go to article

Authors and Affiliations

Stanisław Chmiel
Ewa Maciejewska
Zdzisław Michalczyk
Download PDF Download RIS Download Bibtex

Abstract

The electromagnetic field (EMF) is an environmental factor affecting living organisms. The aim of this study was to demonstrate the effect of an extremely low frequency electro- magnetic field (ELF-EMF) on selected chemical components of the honeybee (Apis mellifera L.) using Fourier Transform Infrared (FTIR) spectroscopy. The FTIR method provides information on the chemical structure of compounds through identification and analysis of functional groups. The honeybees were treated with EMF at a frequency of 50 Hz and magnetic induction of 1.6 mT for 2, 6, 12, 24 and 48 hours. Analysis of FTIR spectra showed that EMF exposure longer than 2 hours induced changes in the structure of chemical compounds, especially in the IR region corresponding to DNA, RNA, phospholipids and protein vibrations, compared to control samples (bees not EMF treated). The results confirm the effect of EMF on bees depending on the duration of exposure.

Go to article

Authors and Affiliations

A. Koziorowska
J. Depciuch
J. Białek
I. Woś
K. Kozioł
S. Sadło
B. Piechowicz
Download PDF Download RIS Download Bibtex

Abstract

This study investigated the suitability of Ijero-Ekiti quartz as a refractory raw material for industrial furnace applications. In order to ascertain its prospective applications, the thermal behaviour, mineralogical composition and chemical composition were determined. Ijero-Ekiti quartz was characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Thermogravimetric and Differential Thermal analysis (TGA and DTA). Its thermal conductivity with specific heat coefficient was determined. The outcome revealed that the quartz sample has a high purity of 94.3% SiO 2, making it suitable as a refractory material. The XRD analysis revealed the presence of alpha-quartz as the dominant crystal phase, which is desirable for refractory applications. The FTIR analysis indicated the absence of hydroxyl (-OH) groups. This indicates a low risk of failure and damage such as spalling, cracking and other forms of damage when produced into bricks. The TGA and DTA displayed significant mass losses and large endothermic bands, which were connected to the dehydroxylation of the quartz rock samples. Based on the demonstrated qualities, the quartz rock sample could be subjected to thermal processing. This study therefore established that Ijero-Ekiti quartz is a suitable raw material for refractory applications due to its high purity, alpha-quartz dominant crystal phase, absence of hydroxyl groups, and uniform morphology.
Go to article

Bibliography

[1] Jongs, L.S., Jock, A.A., Ekanem, O.E. & Jauro, A. (2018). Investigating the industrial potentials of some selected Nigerian clay deposits. Journal of Minerals and Materials Characterization and Engineering. 6, 569-586. DOI: 10.4236/jmmce.2018.66041.
[2] Adeoti, M., Dahunsi, O., Awopetu, O.O., Aramide, F., Alabi, O., Johnson, O. & Abdulkarim, A. (2019). Suitability of selected Nigerian clays for foundry crucibles production. Procedia Manufacturing. 35, 1316-1323. https://doi.org/10.1016/j.promfg.2019.05.023.
[3] Thethwayo, B. & Steenkamp, J. (2020). A review of carbon-based refractory materials and their applications. Journal of the Southern African Institute of Mining and Metallurgy. 120, 641-650. http://dx.doi.org/10.17159/2411-9717/1011/2020.
[4] Fleuriault, C., Grogan, J. & White, J. (2018). Refractory materials for metallurgical Uses. The Journal of The Minerals, Metals & Materials Society. 70, 2420-2421. https://doi.org/10.1007/s11837-018-3096-5.
[5] Sarkar, R. (2016). Refractory technology: Fundamentals and applications. CRC Press, Boca Raton, Florida, United State.
[6] Lee, S. (2015). Types of Refractory Materials and their Applications [Online]. Linkedin. Available: https://www.linkedin.com/pulse/types-refractory-materials-applications-le-sylvia [Accessed June 16 2021]
[7] MARKETS AND MARKETS. (2020). Refractories Market by Form (Shaped Refractories, Unshaped Refractories), Alkalinity (Acidic & Neutral. Basic), End-Use Industry (Iron & Steel, Power Generation, Non-Ferrous Metals, Cement, Glass), and Region - Global Forecast to 2025 [Online]. MARKETSANDMARKETS. Available: https://www.marketsandmarkets.com/Market-Reports/refractories-market-222632393.html?gclid=CjwKCAjwiLGGBhAqEiwAgq3q_mu5-rTCddXNmL2Po9LaVwDTS2rVmPj8dfITLtQzmA4u7BCHkVKZ-RoCur0QAvD_BwE [Accessed June 16 2021].
[8] Ren, C. & Enneti, R.K. (2020). Process design and material development for high-temperature applications. The Journal of The Minerals, Metals & Materials Society. 72. 4028-4029. https://doi.org/10.1007/s11837-020-04381-4.
[9] Patel, N. (2013). Factors affecting the lifespan of cast refractory linings: a general overview. Journal of the Southern African Institute of Mining and Metallurgy. 113, 637-641.
[10] Oyeyemi, A.O., Adekola, F.A., & Olaleye, M.B. (2016). Characterization of Ijero-Ekiti kaolin for industrial applications. Journal of Minerals and Materials Characterization and Engineering. 5(3), 153-160. https://doi.org/10.4236/jmmce.2016.53018.
[11] Adeniyi, F.I., Ogundiran, M.B., Hemalatha, T. & Hanumantrai, B.B. (2020). Characterization of raw and thermally treated Nigerian kaolinite-containing clays using instrumental techniques. SN Applied Sciences. 2, 1-14. https://doi.org/10.1007/s42452-020-2610-x.
[12] Kralik, G., Martins, K.V., Alves, J.R., Sartori, D.V., Scholz, R. & Corat, E.J. (2016). Characterization and utilization of quartz sands in the manufacture of silicon metal. Journal of Cleaner Production. 112, 3304-3311. https://doi.org/10.1016/j.jclepro.2015.06.108.
[13] Guan, Y., Zhang, X., Chen, J. & Wang, L. (2018). Study on thermal shock resistance and high-temperature behavior of quartz-feldspar refractory materials. Journal of the American Ceramic Society. 101(4), 1467-1475. https://doi.org/10.1111/jace.14900.
[14] Zhou, C., Gao, X., Xu, Y., Buntkowsky, G., Ikuhara, Y., Riedel, R., & Ionescu, E. (2015). Synthesis and high-temperature evolution of single-phase amorphous Si–Hf–N ceramics. Journal of the European Ceramic Society. 35(7), 2007-2015. https://doi.org/10.1016/j.jeurceramsoc.2015.01.026.
[15] ASTM C201-93(2019). Standard test method for thermal conductivity of refractories. ASTM International, West Conshohocken, PA, United State.
[16] ASTM C114-22 (2022). Standard test methods for chemical analysis of hydraulic cement. ASTM International, West Conshohocken, PA, United State.
[17] Griffiths, P.R. & De Haseth, J.A. (1986). Fourier transform infrared spectrometry. John Wiley & Sons; New York, United State.
[18] Stodghill, S.P. (2010). Thermal analysis - A review of techniques and applications in the pharmaceutical sciences. American Pharmaceutical Review. 13(2), 29-36.
[19] Craig, D.Q.M., Reading, M. (2007). Thermal analysis of pharmaceuticals. CRC Press, Taylor and Francis Group, Boca Raton, Florida, United State.
[20] Drábik, M. (2017). The challenge of methods of thermal analysis in solid state and materials chemistry. Pure and Applied Chemistry. 89(4), 451-459.
[21] Drabik, M. & Slade, R.C. (2004). Macrodefect-free materials: modification of interfaces in cement composites by polymer grafting. Interface Science. 12(4), 375-379. https://doi.org/10.1023/B:INTS.0000042335.65518.11.
[22] Mojumdar, S.C., Mazanec, K. & Drabik, M. (2006). Macro-defect-free (MDF) cements. Journal of Thermal Analysis and Calorimetry. 83(1), 135-139.
[23] Drábik, M. (2009). Contribution of materials chemistry to the knowledge of macro-defect-free (MDF) materials. Pure and Applied Chemistry. 81(8), 1413-1421. https://doi.org/10.1351/PAC-CON-08-07-16.
[24] Drabik, M., Billik, P. & Galikova, L. (2012). Macro defect free materials; the challenge of mechanochemical activation. Ceramics-Silikáty. 56(4), 396-401. https://doi.org/10.1007/s10973-005-7045-5.
[25] Ahmed, Y.E., Abdulaziz, A.A., Hamid, M.S., Anesh, M.P., Saeed, M.A., Arfat, A. & Mohammad, I.A. (2019). Effect of pyrolysis temperature on biochar microstructural evolution, physicochemical characteristics, and its influence on biochar/polypropylene composites. Applied Science. 9(6), 1-18. https://doi.org/10.3390/app9061149.
[26] Ajala, A.J. & Badarulzaman, N.A. (2016). Thermal conductivity of Aloji fireclay as refractory material. International Journal of Integrated Engineering. 8(2), 16-20.
[27] Vaishnav, H., Navin, K., Kurchania, R. & Ball, R.J. (2022). Synthesis of ZrO2 based nanofluids for cooling and insulation of transformers. IEEE Transactions on Dielectrics and Electrical Insulation. 29(1), 199-205. DOI: 10.1109/TDEI.2022.3148444.
[28] Ajiboye, T.K., Fabiyi, M.O., Mustapha, N. & Abdulkareem, S. (2022). Characterization of clay and granite dust blends as novel materials for energy storage and diffuser in constructing solar flat-plate collector. Tanzania Journal of Science. 48(2), 283-293.
[29] Ritz, M., Vaculíková, L. & Plevová, E. (2010). Identification of clay minerals by infrared spectroscopy and discriminant analysis. Society for Applied spectroscopy. 64(12) 1379-1387.
[30] Yue, C., Liu, J., Zhang, H., Dai, L., Wei, B. & Chang, C. (2018). Increasing the hydrophobicity of filter medium particles for oily water treatment using coupling agents. Heliyon. 4(9), 1-14. DOI: 10.1016/j.heliyon.2018.e00809.
[31] Zaitan, H., Bianchi, D., Achak, O. & Chafik, T. (2008). A comparative study of the adsorption and desorption of o-xylene onto bentonite clay and alumina. Journal of Hazardous Materials. 153(1-2), 852-859. https://doi.org/10.1016/j.jhazmat.2007.09.070.
[32] Gao, J., Jiang, C. & Zhang, X. (2007). Kinetics of curing and thermal degradation of POSS epoxy resin/DDS system. International Journal of Polymeric Materials and Polymeric Biomaterials. 56(1), 65-77. https://doi.org/10.1080/00914030600710620.
[33] Odewole, P.O., Kashim, I.B. & Akinbogun, T.L. (2019). Production of refractory porcelain crucibles from local ceramic raw materials using slip casting. International Journal of Engineering and Manufacturing. 9(5), 56-69. DOI: 10.5815/ijem.2019.05.05.
[34] Oluwagbenga, O.P. & Majiyebo, A.E. (2019). Development of aluminosilicate refractory crucibles from the optimum mix of Awo quartz and Ikere Ekiti clays. ATBU Journal of Science, Technology and Education. 7(2), 331-340.
[35] Shuaib-Babata, Y.L., Ibrahim, H.K., Ajao, K.S., Elakhame, Z.U., Aremu, N.I. & Odeniyi, O.M. (2019). Assessment of physico-mechanical properties of clay deposits in Asa Local Government Area of Kwara State Nigeria for industrial applications. Journal of Research Information in Civil Engineering. 16(2), 2727-2753.
[36] Aremu, D.A., Aremu, J.O. & Ibrahim, U.H. (2013). Analysis of Mubi clay deposit as furnace lining. International Journal of Scientific and Technology. 2(12), 183-186.
[37] Olajide, O.I., Michael, O.B. & Terna, T.D. (2015). Production and characterization of aluminosilicate refractory brick using Unwana beach silica sand, Ekebedi and Unwana clays. British Journal of Applied Science & Technology. 5(5), 461-471.
[38] Osabor, V.N., Okafor, P.C., Ibe, K.A. & Ayi, A.A. (2009). Characterization of clays in Odukpani, south eastern Nigeria. African Journal of Pure and Applied Chemistry. 3(5), 79-85. ISSN 1996 – 0840.
[39] Tenimu, A.A. (2019). Thermogravimetric and differential thermal investigation of rice husk cellulose. Bayero Journal of Pure and Applied Sciences. 12(1), 6-11. http://dx.doi.org/10.4314/bajopas.v12i1.2.
[40] Amkpa, J.A. & Badarulzaman, N.A. (2016). Thermal conductivity of Aloji fireclay Brick. International Journal of Integrated Engineering. 8(3), 16-20.
[41] Silva, K.R, Liszandra, F.A., Camposb, L.N. & Santanaa, D.L. (2019). Use of experimental design to evaluate the effect of the incorporation of quartzite. residues in ceramic mass for porcelain tile production. Materials Research. 22(1), 1-11. https://doi.org/10.1590/1980-5373-MR-2018-0388.
[42] Czichos, H., Saito, T., Smith, L.E. (2011). Springer handbook of metrology and testing. Springer, New York, United State.
[43] Navas, V. G., Sandá, A., Sanz, C., Fernández, D., Vleugels, J., Vanmeensel, K., & Fernández, A. (2015). Surface integrity of rotary ultrasonic machined ZrO2–TiN and Al2O3–TiC–SiC ceramics. Journal of the European Ceramic Society, 35(14), 3927-3941. https://doi.org/10.1016/j.jeurceramsoc.2015.06.018.
[44] Palm, M. & Inden, G. (1995). Experimental determination of phase equilibria in the Fe Al C system. Intermetallics. 3(6), 443-454. https://doi.org/10.1016/0966-9795(95)00003-H.
[45] Wulf, R., Barth, G. & Gross, U. (2007). Intercomparison of insulation thermal conductivities measured by various methods. International Journal of Thermophysics, 28, 1679-1692. https://doi.org/10.1007/s10765-007-0278-8.
[46] Incropera, F.P., DeWitt, D.P., Bergman, T.L., Lavine, A.S. (2007). Fundamentals of heat and mass transfer. John Wiley & Sons; New York, United State.
[47] Hagemann, L. & Peters, E. (1982). Thermal Conductivity- comparison of methods: ASTM-method, hot wire method and its variations. Interceram. 31, 131-135.
[48] Ferber, M.K., Weresczak, A.A. & Hemrick, J.G. (2006). Comprehensive creep and thermophysical performance of refractory materials. United States. DOI:10.2172/885151.
[49] Litovsky, E., Kleiman, J.I. & Menn, N. (2003). Measurement and analysis by different methods of apparent, radiative, and conductive thermophysical properties of insulation materials. High Temperatures-High Pressures. 35(1), 101-108. DOI:10.1068/htjr080.
[50] Arthur, E.K. & Gikunoo, E. (2020). Property analysis of thermal insulating materials made from Ghanaian anthill clay deposits. Cogent Engineering. 7(1), 1-20. https://doi.org/10.1080/23311916.2020.1827493.

Go to article

Authors and Affiliations

B.V. Omidiji
1
O.B. Ogundipe
2
H.A. Owolabi
1

  1. Obafemi Awolowo University, Ile-Ife, Nigeria
  2. Landmark University, Omu-Aran, Nigeria
Download PDF Download RIS Download Bibtex

Abstract

Quantitative evaluation of the microstructure obtained in a product is nowadays commonly required both in R&D activities and during routine quality control of materials and components.
This paper presents an assessment of the quality of ductile cast iron, based on investigations of the effect of chemical composition on the distribution of ductile graphite precipitates in low-alloy cast iron EN-GJS-500-7. The size of graphite precipitates was expressed in terms of equivalent cross-sectional diameter, which made it possible to describe the distribution of graphite precipitates with a function simulating the log-normal distribution of graphite. The resulting U, W and Z parameters were statistically analysed, including the effect of chemical composition on graphite distribution. In the studied cast iron, the components that increase the U parameter are silicon, manganese and phosphorus, thus favourably affecting the total graphite number. In contrast, the constituents that decrease the U parameter are carbon, chromium and aluminium.
Go to article

Bibliography

[1] Cybo, J., Jura, S. (1995). Functional description of isometric structures in quantitative metallography. Gliwice: Silesian University of Technology Publishing House. (in Polish)
[2] Alp, T., Wazzan, A.A. & Yilmaz, F. (2005), Microstructure-property relationships in cast irons. The Arabian Journal for Science and Engineering. 30(2B), 163-175.
[3] Podrzucki, C. (1999). Publishing House. Cracow: STOP. (in Polish).
[4] Angus, H.T. (1978). Cast Iron: Physical and Engineering Properties. London-Boston: Edit Butterworth a. Co.
[5] Jura, S. & Jura, Z. (2001). The influence of the chemical composition and degree of spheroidization of graphite on the mechanical properties mechanical properties of cast iron. Archives of Foundry. 1(1), (2/2), 1-8. ISSN 1642-5308
[6] Ripplinger, C., Gastens, M., Zimmermann, J., Bjӧrn, P., Broeckmann, C., Schrӧder, K-U. & Bührig-Polaczek, A. (2021). Potential of metallurgical gradients in the design of components structural components made of ductile iron. Materials, 14(9), 2411. DOI: 10.3390/ma14092411
[7] Menk, W., Tunzini, S., Rieck, T., Honsel, C. & Weiss, K. (2010). Material development of ductile iron, simulation and production technology for local reinforcement of castings. Key Engineering Materials. 457, 343-348. https://doi.org/10.4028/www.scientific.net/KEM.457.343
[8] Stefanescu, D.M. & Suárez, R. (2020). 90 years of thermal analysis as a control tool in the melting of cast iron. China Foundy. 17(2), 69-84. https://doi.org/10.1007/s41230-020-0039-x
[9] Friess, J., Bührig-Polaczek, A., Sonntag, U. & Steller, I. (2020). From individual graphite assignment to an improved digital image analysis of ductle iron. International Journal of Metalcasting. 14, 1090-1104. https://doi.org/10.1007/s40962-020-00416-3
[10] Bartocha, D. (2006). The structure of EN-GJS-500-7 cast iron depending on the feedstock materials. Archives of Foundry. 6(22), 27-32. ISSN 1642-5308
[11] Materials of Śrem Cast Iron Foundry based in Śrem. Retrieved September 12, 2021, from http://www.proservicetech.it/itacax-thermal-analysis-final-iron-quality-control/
Go to article

Authors and Affiliations

H. Pacha-Gołębiowska
1
ORCID: ORCID

  1. Akademia Nauk Stosowanych im. Jana Amosa Komeńskiego w Lesznie, ul. Mickiewicza 5, 64-100 Leszno, Poland
Download PDF Download RIS Download Bibtex

Abstract

This article deals with the effects of electrical discharge machining (EDM) on the chemical composition and microstructure of cast Alnico alloys, i.e., iron-based alloys composed of aluminum, nickel and cobalt. The experiments focused on determining the chemical composition of the surface layer before and after the EDM process. The microstructure of the material altered by the EDM was also examined. The study included measurement of the thickness of the white layer characteristic of EDM. It is evident that low values of the surface roughness parameters can be obtained by correctly selecting the EDM process parameters. The average surface roughness reported in the experiments was 1 μm. The surface roughness measurements were conducted with a Talysurf CCI lite non-contact profiler. The metrological results also indicate that lower surface roughness can be obtained at small discharge energies.
Go to article

Authors and Affiliations

D. Bańkowski
1
ORCID: ORCID
P. Młynarczyk
1
ORCID: ORCID
B. Szwed
1
ORCID: ORCID

  1. Kielce University of Technology, Poland
Download PDF Download RIS Download Bibtex

Abstract

Metallurgical slags are an object of the increasing interest in terms of the possibility of their utilization, especially as materials used in the construction and road building industries, in the foundry industry for refining and purifying liquid alloys, the production of abrasives for surface treatment of remanufactured machine parts, as mine backfill materials. Metallurgical slags, in order to be used in foundry processes, should be characterized by the stability of the chemical composition. This paper presents the results of statistical analysis calculations, in which using a specific group f samples, knowing their chemical composition, the mean value Ā, variance Ϭ2, standard deviation Ϭ and the classical coefficient of variation V were determined. The research and its results report the amount of variation in considered components of the slags.
Go to article

Authors and Affiliations

Jacek Sitko
1
ORCID: ORCID

  1. Chair of Production Engineering, Silesian University of Technology, Roosevelt Str. 26, 48-000 Zabrze, Poland
Download PDF Download RIS Download Bibtex

Abstract

The objective of this work is to demonstrate for the first time the results of hydrogeochmical studies carried out in the Steinvik River catchment, in order to provide detailed information regarding the chemical composition of groundwater in the Hornsund region, SW Spitsbergen. The water chemistry in the non-glaciated Steinvik River catchment is largely controlled by hydrological processes related to thaw of the near surface permafrost. Groundwater runoff is generated from the fast flow through well-permeable active layer. Recharge from melting snow, permafrost and rain, together with short residence time of groundwater, favors the forming of low-mineralized water, reaching 41 and 50 μS/cm for surface and groundwater, respectively, with the dominance of HCO3−, Cl−, Mg2+, Ca2+ and Na+ ions. In some water samples, increased concentrations of aluminum (up to 268 μg/L ) were found. The highest concentrations of phosphate, nitrite and ammonium in water seem to be related to the presence of bird colonies. Groundwater of active layer in the studied catchment belongs to young meteoric water with the age limited to one summer season.
Go to article

Authors and Affiliations

Michał Rysiukiewicz
1
ORCID: ORCID
Henryk Marszałek
1
ORCID: ORCID
Mirosław Wąsik
1
ORCID: ORCID

  1. Department of Applied Hydrogeology, Institute of Geological Sciences, Wrocław University, Pl. Maksa Borna 9, 50-204 Wrocław, Poland
Download PDF Download RIS Download Bibtex

Abstract

In the 2008 ablation season, subglacial springs discharge, flow rate and profiling of the proglacial river, physical-chemical parameters (pH, temperature, electrical conductivity) and chemical composition (HCO3−, SO42−, Cl−, NO3−, NO2−, PO43−, Ca2+, Mg2+, Na+, K+, Fetot, Mn2+, Al3+, Zn2+, Pb2+ and SiO2) of water in the Werenskiold Glacier forefield were measured. Chemical composition of groundwater as well as water of lakes, the main watercourse, subglacial outflows and water representing direct meltwater recharge were studied to determine their origin, the depth of circulation and recharge systems. The results indicate that the main source of water in the glacial river were the subglacial outflows in the central part of the glacier. They generated 77% of the total amount of water in the glacier forefield. Direct inflow of groundwater from glacier moraine to proglacial river was marginally low and the water circulation system was shallow, fast and variable. There were no evidences for an important role of deeper than suprapermafrost water circulation systems. The water temperature, especially in the lakes, exceeding the mean daily air temperature during the ablation period, is due to the heating of the ground moraine rocks. A clear difference between groundwater chemical composition and surface water as well as subglacial runoff in terms of major ions, together with the homogeneity of chemical composition of the proglacial river from spring to mouth confirmed the marginal role of groundwater runoff in the drainage of the catchment area. It was confirmed that the chemical composition of groundwater and moraine lakes in the glacier forefield was shaped by geological factors, i.e., mainly chemical weathering of sulphides, carbonates and secondary sulphates. The possibility of secondary iron hydroxide precipitation and a high probability of complex aluminosilicate transformations were also demonstrated.
Go to article

Authors and Affiliations

Magdalena Modelska
1
Sebastian Buczyński
1

  1. University of Wrocław, Institute of Geological Sciences, Plac M. Borna 9, 50-204 Wrocław, Poland
Download PDF Download RIS Download Bibtex

Abstract

Changes in chemical composition of the surface waters percolated through the soil and running off from the penguin rookeries are described. It was found, that the chemical composition of waters flowing from the breeding places depends on the size and rate of precipitation, and also on the location of rookeries. The longer and more complicated is the run off route of waters from the terrain of rookery, the more diluted are the solutions that reach the sea. In such case a significant part of phosphorus contained in the fecal materials may be retained on land, while most of ammonia volatilizates into the atmosphere.

Go to article

Authors and Affiliations

Andrzej Tatur
Andrzej Myrcha
Download PDF Download RIS Download Bibtex

Abstract

Bacterial, enzymatic and chemical analyses pointed to active microbiological mineralization and transformation of penguin excrements at "maritime Antarctic". The following physiological groups of bacteria were found: proteolitic, amonifying, nitrifying, lecithin degrading, Са3(Р04 ) 2 dissolving, chitin degrading and spore forming ones. The number of molds was not significant. The nitrate reducers and N2 — fixing bacteria were not detected. About 50% of С and N were volatilized during three weeks. Some parts of N — NH3 was oxidized to N — NO3 in surface layer of the soil. The content of P increased during degradation of penguin excrements. About 1/3 part of total organic carbon content in bird excrements residues was derived from chitin.

Go to article

Authors and Affiliations

Stanisław J. Pietr
Andrzej Tatur
Andrzej Myrcha
Download PDF Download RIS Download Bibtex

Abstract

The surface properties of particles emitted from six selected coal-fired power and heating plants in Poland have been studied in this work for the first time. Samples were collected beyond the control systems. Surface composition of the size-distributed particles was obtained by photoelectron spectroscopy (XPS).

The reflection of the smallest, submicron particles was also measured to calculate their specific/mass absorption. The surface layer of the emitted particles was clearly dominated by oxygen, followed by silicon and carbon. The sum of the relative concentration of these elements was between 85.1% and 91.1% for coarse particles and 71.8–93.4% for fine/submicron particles. Aluminum was typically the fourth or fifth, or at least the sixth most common element. The mass absorption of the submicron particles emitted from the studied plants ranged from 0.02 m2g-1 to 0.03 m2g-1. Only specific absorption obtained for the “Nowy Wirek” heating plant was significantly higher than in other studied plants probably because the obsolete fire grate is used in this heating plant.

The obtained results suggest that the power/heating-plant-emitted fine particles contain less carbonaceous material/elemental carbon on their surfaces than those that are typical in urban air.

Go to article

Authors and Affiliations

Józef S. Pastuszka
Jan Konieczyński
Ewa Talik
Download PDF Download RIS Download Bibtex

Abstract

The paper presents the experimental results on the determination of melt parameters such as the energy of the boundary, contact angle, density and kinematic viscosity of low and medium alloy steels at different temperatures, as well as the dispersion of their dendritic structure in solidified castings. The analysis of the data obtained allowed revealing using mathematical models the influence of the chemical composition and temperature of melts on their properties and the dendritic structure of castings. It was established the variation of the melt parameters depending on the particular chemical elements of steels as C, Si, Mn, O, P, V, Cr. The established analytical dependences shown that increasing density and viscosity contributes to the dispersion of the dendritic structure and viscosity is of the major effect. The derived quantitative patterns allows to evaluate structure formation of cast structural low and medium alloy steels.
Go to article

Bibliography

[1] Volmer, M. (1939). Kinetik der Phasenbildung. Dresden, Leipzig, Steinkopf.
[2] Frank, F. (1949). Model grow crystallization. Discusion of the Faraday Society. 5, 48-54.
[3] Frenkel, Ya.I. (1975). Kinetic theory of liquid. M.: Publishing House of the Academy of Sciences of the USSR.
[4] Wilson, D.P. (1965) Structure of liquid metals and alloys. Metallurgical Reviews, 10(1), 381-590.
[5] Cao, Y.F., Chen, Y., Ma, X.P., Fu, P.X., Kang, X.H., Liu, H.W., Li, D.Z. (2016). The effect of alloy elements on the density variation of steel melt at the interdendritic region during solidification. In 4th International Conference on Advances in Solidification Processes (ICASP-4). IOP Conf. Series: Materials Science and Engineering, 8-11 July 2014 (pp. 1-7).
[6] Arsentiev, P.P., Koledov, L.A. (1976). Metallicheskie rasplavy i ih svojstva [Metal melts and their properties]. Moskva: Metallurgiya [In Russian].
[7] Ershov, G.S., Bychkov, Yu.B. (1982). Fiziko-himicheskie osnovy racionalnogo legirovaniya stalej i splavov [Physical and chemical bases of rational alloying of steels and alloys]. Moskva: Metallurgiya [In Russian].
[8] Ryzhonkov, D.I., Arsentiev, V.V., Yakovlev, V.V. (1989). Teoriya metallurgicheskih processov [Theory of metallurgical processes]. Moskva: Metallurgiya [In Russian].
[9] Kupriyanov, A.A. & Filippov, S.I. (1968). Density and structural changes of iron and alloys of iron with carbon. Izv.vuz. Ferrous metallurgy. 9, 10-15.
[10] Ershov, G.S., Bychkov, Yu.B. (1983). Svojstva metallurgicheskih rasplavov i ih vzaimodejstvie v staleplavilnyh processah [Properties of metallurgical melts and their interaction in steelmaking processes]. Moskva: Metallurgiya [In Russian].
[11] Goldstein, Ya.E., Mizin, V.G. (1986). Modificirovanie i mikrolegirovanie chuguna i stali [Modification and microalloying of cast iron and steel]. Moskva: Metallurgiya [In Russian].
[12] Grigoryan, V.A., Belyanchikov, L. N., Stomakhin, A.Ya. (1987). Teoreticheskie osnovy elektrostaleplavilnyh processov [Theoretical fundamentals of electric steelmaking processes]. Moskva: Metallurgiya [In Russian].
[13] Baum B.A. (1979). Metallicheskie zhidkosti - problemy i gipotezy [Metallic liquids - problems and hypotheses]. Moskva: Nauka [In Russian].
[14] Feng, G., Jiao, K., Zhang, J. & Gao, S. (2021). High-temperature viscosity of iron‑carbon melts based on liquid structure: The effect of carbon content and temperature. Journal of Molecular Liquids. 330, 115603, 1-10. https://doi.org/10.1016/j.molliq.2021.115603.
[15] Turnbull, D. & Fisher, J.C. (1949). Rate of Nucleation in Condensed Systems. Journal of Chemical Physics. 17, 71.
[16] Popel, S.I. (1971). Teoriya metallurgicheskih processov [Theory of metallurgical processes]. Moskva: VINITI [In Russian].
[17] Efimov, V.A., Eldarkhanov A.S. (2004). Tehnologii sovremennoj metallurgii [Technologies of modern metallurgy]. Moskva: Novye tehnologii [In Russian].
[18] Volmer, M.I., Mаnder, M. (1931). Journal of Chemical Physics. A154, 97.
[19] Flemings, M. (1974). Solidification processing. New York: Mc Graw – Hill book company.
[20] Hilling, W.B., Turnbull, D. (1956) Theory of Crystal Growth in Undercooled Pure Liquids. Journal of Chemical Physics. 24(4), 914.
[21] Turnbull, D. (1949). Thermodynamics in Metallurgy, ASM, Metals Park, Ohio.
[22] Baum, B.A. (1988). About of the relationship of liquid and solid metallic states. Rasplavy. 2(2), 18-32.
[23] Arsentiev, P.P., Yakovlev, V.V., Krashennikov, M.G. (1988). Fiziko-himicheskie metody issledovaniya metallurgicheskih processov [Physico-chemical methods for studying metallurgical processes]. Moskva: Metallurgiya [In Russian].
[24] Shvedkov, E.L. (1975). Elementarnaya matematicheskaya statistika v eksperimentalnyh zadachah materialovedeniya [Elementary mathematical statistics in experimental problems of materials science]. Kiev: Naukova dumka [In Russian].
[25] ImageJ. Image Processing and Analysis in Java. Retrieved September 11, 2023 from: https://imagej.nih.gov/ij/.
[26] Vitol, E.N. & Orlova K.B. (1984). About the energy of the boundary of liquid metals. Izv. USSR Academy of Sciences Metals. 4, 37-42.
[27] Svidunovich, N.A., Glybin, V.P., Svirko, L.K. (1989). Vzaimodejstvie komponentov v splavah [Interaction of components in alloys]. Moskva: Metallurgiya [In Russian].
[28] Chalmers, B. (1968). Teoriya zatverdevaniya [Theory of Solidification]. Moskva: Metallurgiya [In Russian].  


Go to article

Authors and Affiliations

Y. Aftandiliants
1
ORCID: ORCID
S. Gnyloskurenko
1 2
ORCID: ORCID
H. Meniailo
3
ORCID: ORCID
V. Khrychikov
3
ORCID: ORCID

  1. National University of Life and Environmental Sciences of Ukraine, Ukraine
  2. Physical and Technological Institute of Metals and Alloys, National Academy of Sciences of Ukraine, Ukraine
  3. Ukrainian State University of Science and Technologies, Ukraine
Download PDF Download RIS Download Bibtex

Abstract

It appears from the analysis of the chemical composition of macroalgae of the Antarctic: Adenocystis utricularis and Himantothallus grandifolius (brown algae), Leptosomia simplex (red algae) and Monostroma hariotti (green algae) that the examined algae, brown algae in particular (mainly Adenocystis utricularis), are rich in mineral components, primarily: sodium, potassium, hologens, and structural polysaccharides. Organic substances, such as: proteins, amino acids, lipids, fatty acids, saccharides reduction, chlorophylls and carotenoids, occur in the analysed algae in quantities much smaller in comparison with taxonomically similar macroalgae derived from marine environment having more favourable hydrochemical and climatic conditions.

Go to article

Authors and Affiliations

Romuald Czerpak
Anna Mical
Ryszard Gutkowski
Irena Siegień
Irena Jackiewicz
Download PDF Download RIS Download Bibtex

Abstract

Concentrations and elemental composition of fine (PM2.5) and coarse (PM2.5-10) ambient particles,

at two sampling points located at the same urban background sites, were investigated. The points were 20 m

distant from each other and at various heights (2 and 6 m) above the ground. A dichotomous sampler, equipped

with a virtual impactor, and a cascade impactor were used to sample the dust. An X-ray fluorescence spectrometer was used in the elemental analyses. The investigations revealed heterogeneity of the spatial distribution

and the elemental composition of suspended dust at the investigated urban background site. Coarse dust, whose

concentration at 2.0 m above the ground was affected by secondary emission from roads, soil and other local

low-level sources in some periods, appeared more heterogeneous.

Go to article

Authors and Affiliations

W. Rogula-Kozłowska
B. Błaszczak
K. Klejnowski
Download PDF Download RIS Download Bibtex

Abstract

Requirements for environmental protection, such as reducing emissions of CO2, NOx, and SO2 are the reason for growing interest in new technologies for coal utilization. One of the most promoted technologies is coal gasification. However, like any technology using coal, this process produces wastes – fly ash and slag. Due to the small number of coal gasification plants, these wastes are poorly understood. Therefore, before making decisions on the introduction of coal gasification technology, a waste utilization plan should be developed. This also applies to the slags formed in underground coal gasification technology. One of the options under consideration is to use these wastes as a component in mineral binders of a pozzolanic character. This paper compares the properties of two types of slags. The first slag (MI) comes from fuel gasification, and the second slag (BA) is from underground coal gasification. Slag MI can be classified as basic slag with a chemical composition similar to that of silica fly ash from coal combustion. Slag BA – because of its four times greater content of calcium oxide – belongs to a group of weakly basic slags. The main and only mineral component of slag MI is glassy phase. Slag BA forms – besides the glassy phase – crystalline phases such as mullite (3 Al2O3 · 2 SiO2), quartz (-SiO2), anorthite (Ca(Al2Si2O8)), gehlenit (Ca2Al[(Si,Al)2O7]), wollastonite (Ca3[Si3O9]), 2CaO · SiO2, and 4 CaO · Al2O3 · Fe2O3. The results of analyses have shown that slag BA has better pozzolanic properties (the pozzolanic activity index is 75.1% at 90 days) than slag MI (69.9% at 90 days) The preliminary studies lead to the conclusion that these slags are characterized by very low pozzolanic activity and cannot be used as a pozzolanic material.

Go to article

Authors and Affiliations

Maciej Mazurkiewicz
Ewelina Tkaczewska
Radosław Pomykała
Alicja Uliasz-Bocheńczyk
ORCID: ORCID

This page uses 'cookies'. Learn more