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1

Bottom Sediments in a River Under Acid and Alkaline Wastewater Discharge

Kharko Polina Alexandrovna, Matveeva Vera Anatol'evna

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 3

35--41

EN

The drainage flows of metal loads into the drainage and infiltration waters of mine dumps of enterprises have a dramatic effect on small rivers in industrial regions. The paper considers the outcomes of geochemical monitoring of the Karagaily River and assesses the transformation of the acid-base conditions depending on the influence of the facilities of the enterprise. The results of engineering and environmental surveys, including sampling of bottom sediments, laboratory preparation, chemical elemental analysis of samples and X-ray diffraction analysis of mineral composition, were presented. A complex technogenic alkaline sorption-hydroxide barrier was found at the mixing point of acidic river waters (the influence of dump and quarry waters) and alkaline wastewater of treatment facilities, where the deposited iron hydroxide adsorbs ore minerals, which reduces their outflow into larger rivers and increases the self-purification potential of the river. Further interaction of iron hydroxide with the acid mine drainage and calcium bicarbonate of wastewater results in pyritization of bottom sediments. Excavation and dewatering of the pyrite-containing bottom sediments will allow their joint use with tailings and ore-processing waste for re-extraction useful components.

2

Characterisation of Mg-Zn-Ca-Y powders manufactured by mechanical milling

Lesz S., Tański T., Hrapkowicz B., Karolus M., Popis J., Wiechniak K.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 103, nr 2

49--59

EN

Purpose: This paper explains mechanical synthesis which uses powders or material chunks in order to obtain phases and alloys. It is based on an example of magnesium powders with various additives, such as zinc, calcium and yttrium. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD) method, scanning electron microscopy (SEM), determining particle size distributions with laser measuring, Vickers microhardness. Findings: The particle-size of a powder and microhardness value depend on the milling time. Research limitations/implications: Magnesium gained its largest application area by creating alloys in combination with other elements. Magnesium alloys used in various industry contain various elements e.g. rare-earth elements (REE). Magnesium alloys are generally made by casting processes. Consequently, the search for new methods of obtaining materials such as mechanical alloying (MA) offers new opportunities. The MA allows for the production of materials with completely new physico-chemical properties. Originality/value: Thanks to powder engineering it is possible to manufacture materials with specific chemical composition. These materials are characterized by very high purity, specified porosity, fine-grain structure, complicated designs. These are impossible to obtain with traditional methods. Moreover it is possible to refine the process even further minimalizing the need for finishing or machining, making the material losses very small or negligible. Furthermore material manufactured in such a way can be thermally or chemically processed without any problems.

3

The role of mineral phases in the biogas production technology

Geršl M., Kanduč T., Matýsek D., Šotnar M., Mareček J.

Ecological Chemistry and Engineering. S

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2018

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Vol. 25, nr 1

51--59

EN

In the field of electric power industry, renewable energy sources, fertilisers, reclamation, and waste management, biomass is widely studied and used. Minerals are present in every step of biogas transformation, but their forms, occurrence, and composition have not been studied yet. However, there is no comprehensive study research that would address the presence of mineral phases in the process of biogas production. This aim of the study is determination of the amount and composition of the mineral phases present in fermentation residues resulting from different production technologies. Digestate mineral composition was analysed using 46 samples from agricultural biogas plants and university testing biogas reactor. The majority of samples contained the amorphous phase. Minority phases consisted of quartz, albite, orthoclase, muscovite, and amphibole. Opal-CT was found in eleven samples (1.26 to 12.1% wt.). The elements present in gas-liquid fluids or in liquids, gases and aerosols within the biogas technology system may create mineral phases, namely the amorphous phase or the crystalline phase under certain conditions. Opal-CT may enter the fermenter as part of plant tissues referred to as phytoliths, or as an unwanted admixture of different origin. It may also originate from the present amorphous SiO2.

4

Mechanical behaviour and phase transition mechanisms of a shape memory alloy by means of a novel analytical model

Carpinteri A., Di Cocco V., Fortese G., Ronchei C., Scorza D., Vantadori S., Zanichelli A., Iacoviello F., Natali S.

Acta Mechanica et Automatica

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2018

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Vol. 12, no. 2

105--108

EN

The aim of the present paper is to examine both the fatigue behaviour and the phase transition mechanisms of an equiatomic pseudo-elastic NiTi Shape Memory Alloy through cyclic tests (up to 100 loading cycles). More precisely, miniaturised dog-bone specimens are tested by using a customised testing machine and the contents of both austenite and martensite phase are experimentally measured by means of X-Ray diffraction (XRD) analyses. On the basis of such experimental results in terms of martensite content, an analytical model is here formulated to correlate the stress-strain relationship to the phase transition mechanisms. Finally, a validation of the present model by means of experimental data pertaining the stress-strain relationship is performed.

5

Przygotowanie mieszanek geopolimerowych z produktów ubocznych z cegielni

Fořt J., Vejmelková E., Keppert M., Černý R.

Cement Wapno Beton

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2017

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R. 21/83, nr 6

457--465

PL

Aktywowane alkalicznie materiały mineralne są obecnie postrzegane jako postępowa metoda otrzymywania spoiw o właściwościach porównywalnych z cementem portlandzkim. W ramach tych badań odpady produkcyjne z cegielni w Republice Czeskiej aktywowane alkalicznie zastosowano do otrzymywania mieszanek geopolimerowych. Zbadano wpływ różnych stosunków SiO2/Al2O3 i Na2O/SiO2 w składzie aktywatorów w celu oceny ich znaczenia na właściwości geopolymerów po stwardnieniu. Sprawdzono także podstawowe właściwości fizyczne oraz strukturę porów po 28 i 90 dniach oraz porównano je z oznaczeniami rentgenograficznymi składu fazowego. Na podstawie uzyskanych wyników oceniono wpływ składu aktywatorów na właściwości geopolimerów.

EN

Alkali activated mineral materials are nowadays perceived as one of progressive ways to propose competitive binder systems comparable to ordinary Portland cement. Within this study, by-products from brick factories in the Czech Republic, together with a mixture of alkaline activators, are used for the preparation of geopolymer mixes. The effect of various combinations of SiO2/AI2O3 and Na2O/SiO2 ratios is studied, in order to evaluate their influence on the properties of geopolymers in hardened state. The basic physical properties, pore distribution and mechanical strength after 28 and 90 days are determined and the obtained results are linked to the information provided by X-ray diffraction experiments. Based on the gathered data, the effect of particular molar ratios on material properties is analysed.

6

Synthesis, Thermal and Crystallographic analysis of 1,1’-diylbis(2-methyl-4-phenylene)bis(2-nitrobenzoate)cyclohexane

Bhavin B. Dhaduk, Chirag B. Patel, Parsania P. H.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 45

32--41

EN

The crystal structure of 1,1’-diylbis (2-methyl-4-phenylene) bis (2-nitrobenzoate) cyclohexane (NBM-2) has been determined by X-ray crystallographic technique. Single crystals were grown by slow evaporation technique. NBM-2 crystallized in the triclinic crystal lattice having space group P-1. Both the phenyl rings are perpendicular to the cyclohexane ring having chair conformation. NBM-2 showed both inter-and intramolecular interactions. The structure of NBM-2 has also been supported by FT-IR, 1HNMR, 13C NMR, MS techniques. The thermal behaviour of NBM-2 were studied by TGA and DSC techniques at heating rate of 10oC min-1 in nitrogen atmosphere. Thermal stability and kinetic parameters were determined according to Anderson-Freeman method and discussed .

7

Surface modified cellulose obtained by acetylation without solvents of bleached and unbleached kraft pulps

Olaru N., Olaru L., Vasile C., Ander P.

Polimery

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2011

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T. 56, nr 11-12

834-840

EN

Heterogeneous acetylation to a low extent of bleached and unbleached commercial kraft pulps was performed with acetic anhydride without solvents and in the presence of sulfuric acid catalyst. The process was conducted in an effort to change the polarity of studied kraft pulps and to improve their compatibility with synthetic polymers without changing their fibrous structure. It was observed that the fiber morphology does not change up to a reaction time of 3 h for both investigated materials. The hydrophilic character of the bleached pulp was decreased by acetylation to a low extent, while the unbleached material showed an initial increase of water retention capacity. At higher degrees of modification, both pulps exhibited similar hydrophilic properties. For both materials, an initial slightly increased susceptibility to enzymatic attack with cellulase from Trichoderma reesei was observed, however the acetylated bleached cellulose fibers were more susceptible to enzymatic attack than those of the unbleached material.

PL

Używając bezwodnika octowego przeprowadzono bez rozpuszczalników, w obecności kwasu siarkowego jako katalizatora, heterogeniczne acetylowanie bielonej (AC) i niebielonej (ACM) celulozowej masy siarczanowej (rys. 1 i 3). Miało to na celu zmianę jej polarności i poprawę kompatybilności z tworzywami polimerowymi bez zmiany struktury włókien celulozy. Badano wpływ czasu trwania tego procesu na właściwości otrzymywanych próbek. Zaobserwowano, że w przypadku obu rodzajów masy celulozowej (AC i ACM) morfologia włókien nie ulega zmianie jeżeli proces prowadzi się nie dłużej niż 3 h (rys. 6). Hydrofilowy charakter bielonej masy celulozowej uległ zmniejszeniu dzięki przeprowadzonemu w niewielkim stopniu acetylowaniu. Próbki niebielonej masy charakteryzował początkowo wzrost zdolności pochłaniania wody, ale przy wyższych stopniach acetylacji oba rodzaje mas wykazywały taki sam charakter hydrofilowy. W przypadku obu mas podatność na enzymatyczny atak z użyciem celulozy pochodzącej z Trichoderma reesei początkowo słabo wzrastała ze wzrostem stopnia acetylacji, aby następnie zmniejszyć się do poziomów niższych niż początkowe. Włókna bielonej i acetylowanej celulozy były bardziej wrażliwe na ten atak niż te zawarte w niebielonej próbce (rys. 9).

8

Określanie właściwości popiołów lotnych przy użyciu różnych metod i urządzeń badawczych

Szponder D. K., Trybalski K.

Górnictwo i Geoinżynieria

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2009

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R. 33, z. 4

287-298

PL

Popioły lotne są uciążliwymi odpadami, powstającymi z substancji mineralnych zdyspergowanych w węglu, które w wyniku jego spalenia ulegają wielu procesom fizykochemicznym. Ze względu na zastosowanie różnych metod spalania węgla, różnorodnego składu paliwa, wysoki stopień dyspersji substancji mineralnych paliwa oraz gwałtowność procesów termicznych, ziarna popiołu wykazują wysoki stopień zróżnicowania morfologicznego, składu fazowego i chemicznego. Sprawia to, że poszczególne rodzaje popiołów lotnych znacznie różnią się właściwościami, dlatego też dobór odpowiedniej metody ich utylizacji wymaga dogłębnego poznania ich właściwości fizyko-chemicznych i mineralogicznych. W publikacji zaprezentowano wybrane metody i urządzenia pomiarowe wykorzystywane do określania właściwości fizycznych surowców i odpadów mineralnych, a także ukazano możliwości ich zastosowania do scharakteryzowania właściwości popiołów lotnych.

EN

Fly ash is noxious waste that comes from minerals substances dispersed in coal and are subjected to many physical and chemical processes during coal combustion. Because of different types of coals, different types of combustion, a high level of dispersion of mineral substances in coals and the duration of thermal processes, the particles of fly ash are diversified as to their structure, phase and chemical composition. The diversity of produced fly ash makes it necessary to determinate their physical, chemical and mineralogical properties in order to select suitable utilization method. This paper presents a few research methods and measuring devices used to determine physical, chemical and mineralogical properties of raw and waste materials and also their usefulness to characterize fly ashes properties.

9

Rozwój zastosowań rentgenowskiej analizy dyfrakcyjnej

Krztoń H., Dobrzański J., Smolec B., Marczak Z., Zieliński A., Łapczyński Z., Głowacki P.

Prace Instytutu Metalurgii Żelaza

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2008

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T. 60, nr 2

63-68

PL

Zastosowano metody wykorzystujące zjawisko dyfrakcji rentgenowskiej na materiałach polikrystalicznych w badaniach procesów wydzieleniowych, w analizie naprężeń w elementach konstrukcyjnych oraz do pomiaru gęstości dyslokacji w materiałach ferromagnetycznych. Opracowano także projekt systemu automatycznego sterowania pracą generatora dyfraktometru Philips PW 1140. Badania nad przebiegiem procesu wydzieleniowego przeprowadzono na elementach instalacji energetycznych, wykonanych ze stali 15HM, stwierdzając zależność pomiędzy czasem eksploatacji a udziałem poszczególnych rodzajów węglików. Badania naprężeń wykonano na kulkach łożyskowych, na próbkach walca żeliwnego, pobranych z obszaru pęknięcia oraz na elementach wyciętych z kół zębatych. Analizowano zmierzone sygnały szumu Barkhausena oraz przebiegi strumienia magnetycznego w funkcji stanu materiału, a szczególnie gęstości dyslokacji w próbkach pobranych z główki, stopki i środnika szyny typu 60E2 po prostowaniu oraz w próbce stali w gatunku 42CrNiMo4 pobranej z wału korbowego po obróbce cieplnej.

EN

Methods using the X-ray diffraction effect on polycrystalline materials were used in the research of precipitation processes, in analysis of stresses in constructional components and for measurement of dislocation density in ferromagnetic materials. The design of a system for automatic control of Philips PW 1140 diffraction instrument's generator was developed too. The investigations of the course of precipitation process were carried out on the components of power systems made from 15HM steel, finding the relationship between the operation time and the contents of individual types of carbides. The stress tests were carried out on bearing balls, cast-iron roll samples taken from the cracking area and elements cut out of the gear wheels. The measured Barkhausen noise signals and the runs of magnetic stream versus the material condition, in particular dislocation density in the samples taken from the head, foot and web of the 60E2-type rail after straightening and in the 42CrNiMo4 steel sample taken from the crankshaft after heat treatment, were analysed.

10

Badanie właściwości fazy skondensowanej metoda! Emisji niskoenergetycznych elektronów wspomagana analiza rentgenograficzna

Gągorowska B., Duś-Sitek M.

Inżynieria Powierzchni

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2006

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nr 2

87-91

PL

W pracy przedstawiono właściwości układów wielowarstwowych Cu/Ni wykorzystując metodę emisji niskoenergetycznych elektronów wspomaganą analizą rentgenograficzną. Otrzymane obrazy dyfrakcyjne dla układów przed nagrzewaniem wykazały obecność pików satelickich, z kolei dla próbek nagrzewanych do temperatury 933 K struktura ich została zachwiana. Z badań metoda emisji elektronów otrzymano krzywą emisyjną, na której obserwuje się dwa maksima. Nagrzewanie wymusza proces rozrostu obszarów nanokrystalicznych, tworzenia granic międzyfazowych oraz wystąpienie zjawisk transportowych. Aby uzyskać pełne informacje na temat emisji elektronów badano także stan powierzchni obydwu rodzajów próbek. Ponieważ zjawisko emisji elektronów wykorzystano jako metodę do kompleksowego badania faz krystalicznych, w pracy wykazano, że metodę tą można również wykorzystać do badania nanokrystalicznych struktur wielowarstwowych.

EN

The exoemission properties of multi-layered Cu/Ni systems are presented. Samples were tested using emission of low-energetistic electrons. Furthermore, the x-ray diffraction analysis was made to determine the quality of the multi-layer structure. The x-ray diffraction spectra for systems before heat treatment showed the presence of satellite peaks. Heating of samples up to 933 K induced some distortion of their structure. Investigation of electron emission resulted in determining the temperature dependence of the emission intensity, with characteristic two maxima peaks. Heat treatment of samples provokes the growth of nanocrystalline clusters, the formation of interfacial boundaries as well as pronouncement of transport phenomena. To obtain full information about emission of electrons, the surface topography of Cu/Ni superlattices was investigated. Until now electron emission phenomenon was used as a method of complex investigations of crystalline phase properties. The aim of this paper is to demonstrate, that the electron emission method is a valuable tool to investigate the nanocrystalline multi-layer structures.

11

Steatite ceramics mechanical durability behavior with regard to steatite polymorphism

Mielcarek W., Nowak-Woźny D., Prociów K.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

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2004

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Vol. 40, nr 15

224-228

EN

Crystallites developed in steatite ceramics during sintering are the protoenstatite. The size of crystallites depends on temperature. During cooling protoenstatite crystallites invert to clinoenstatite ones, what is the cause of steatite ceramics deterioration and the loss on steatite mechanical endurance. The loss of mechanical endurance is strictly correlated with the degree of proto to clinoenstatite inversion. It was find out that there is much greater tendency for large protoenstatite to invert to clinoenstatite than for small ones. The temperature 1350 °C was find optimal for formation small, well crystallized protoenstatite crystals. This is also the temperature for which the temperature of protoenstatite to clinoenstatite inversion is the lowest and it is 250 °C.

12

Zastosowanie nowoczesnych metod badawczych w inżynierii mineralnej

Kędzior A., Trybalski K., Konieczny A.

Inżynieria Mineralna

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2003

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nr S. 3

155-165

PL

W referacie przedstawiono nowoczesne metody badawcze: skaningową mikroskopię elektronową oraz rentgenowską analizę dyfrakcyjną. Omówiono właściwości tych metod oraz ich zastosowanie w różnych dziedzinach inżynierii mineralnej. Wykorzystując opisane metody przeprowadzono badania produktów wzbogacania flotacyjnego rudy miedzi. Przedstawiono wstępne wyniki w formie zdjęć i mapek skaningowych oraz dyfraktogramów. Zawierają one informacje dotyczące składu mineralogicznego badanych materiałów, składu pierwiastkowego, morfologii powierzchni próbek. Dzięki tym metodom możliwa jest pełniejsza ocena i kontrola produktów procesów wzbogacania.

EN

The article presents modern research methods: scanning electron microscopy as well as X-ray diffraction analysis. Proprieties of these methods as well as their use in different fields of mineral engineering were presented. With use of the described methods there were done researches on products of copper ore flotation enrichment. Preliminary results were shown introduced in form of pictures, scan maps and diffraction patterns. They contain information on mineralogical composition of studied materials, elemental composition, samples surface morphology. Thank to these methods a more exhaustive evaluation and control of enrichment products is possible.

13

Residual stresses in nitrided layers on titanium alloys produced under glow discharge conditions.

Wierzchoń T., Major B., Wołczyński W.

Inżynieria Materiałowa

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1998

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R. XIX, nr 4

1007-1010

EN

Plasma nitriding treatment of titanium alloys is performed to improve the frictional wear and corrosion resistance. Titanium alloys OT4-0 were treated at various temperatures. The X-ray diffraction phase analysis revealed the TiN, Ti2N and TiN0.30 phases in the surface layers when the process was completed. Respective relations between the identified phases varied slightly in respect to the process conditions. The X-ray square sin psi method was used to measure residual stresses within the surface layers of examined alloys subjected formerly to the plasma nitriding. Calculations of the residual stresses were carried out mainly for the TiN phase on the basis of the 311 diffraction line. The level of residual stresses was within the range of about -2.2 to -3.2 GPa in respect to the applied experimental nitriding conditions for measurements of the front surface. Measurements performed for the back surface revealed diminishing of the stress level of about -1.8 to -2.8 GPa, respectively. An attempt was made to estimate residual stresses in the other constituent phases i.e. Ti2N and TiN0.30, the values for the TiN were used in calculations. The obtained results presented also the compresive residual stresses of order -1.6 to -2.4 GPa for the Ti2N and -1.4 to 2.0 GPa for the TiN0.30. Increase of resistance to corrosion and to frictional wear was stated in the plasma nitrided materials.

14

Processing and mechanical properties of mechanically alloyed niobum-rich Nb-Al alloys.

Dymek S., Dollar M., Leonard K., Wróbel M.

Inżynieria Materiałowa

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1998

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R. XIX, nr 4

1147-1152

EN

Four Nb-Al alloys containing 15%, 18%, 20% and 25% at. Al were successfully processed by mechanical alloying followed by hot pressing. Analysis of X-ray spectra as well as transmission electron microscopy studies revealed the presence of four phases: niobum solid solution (Nbss), NB3Al, Nb2Al and dispersoids of Al2O3. The grain size was estimated to be = 1 micrometre. The improvement in strength of the mechanically alloyed material was due to the refined grain size and oxide dispersion in the microstructure. The alloys exhibited only limited compressive ductility at room temperature but were ductile at 1000 degrees centigrade. The mechanism for creep deformation in the examined Nb-Al alloys is postulated to be dislocation creep through diffusion controlled climb.