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1

Effect of fertilisation with P, Mg or S enriched urea-ammonium nitrate solution on the management of macronutrients in common maize

Wierzbowska Jadwiga, Sienkiewicz Stanisław, Światły Arkadiusz

Journal of Water and Land Development

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2023

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no. 57

39--51

EN

The purpose of this study has been to determine the effect of fertilisation with urea-ammonium nitrate (UAN) solution enriched with P, Mg or S on the content of macronutrients in the grain and straw of maize. The following fertilisers were tested in the field experiment: ammonium nitrate, urea, UAN - 32% N; RSM+S - 26% N + 3% S; RSM+P(Medium) - 26% N and 4.80% P; RSM+P(Starter) - 21% N and 7.86% P; UAN + Mg - 20% N + 4% Mg. In each year of the experiment, significant differentiation in the contents of P, K, Ca, Mg and S in maize grain and straw was observed, depending on the applied nitrogen fertilisation. However, considering the average values from each treatment achieved over the three years, it was demonstrated that the fertilisation significantly changed only the content of P and S in grain and K and Ca in straw of maize. The removal of nutrients was the highest in the second year of the research and amounted in kg∙ha-1 : P - about 100, K - about 350, Ca - about 80, Mg - about 35 and S - about 31, which in turn were differentiated over the years of the experiment in the three years. The removal of P, K, Mg and S also significantly depended on fertilisation. Significant differences, however, most often concerned the control treatment relative to the fertilised ones. The contribution of grain to the accumulation of nutrients also varied significantly in the three years of the experiment. Significantly the lowest share of grain in terms of P and S accumulation was noted in maize grown without N fertilisation.

2

The Effects of Various Organic Materials on Dactylis glomerata Yield and Content of Selected Macroelements

Malinowska Elżbieta, Wiśniewska-Kadżajan Beata, Ostaszewska Urszula, Horaczek Tomasz

Journal of Ecological Engineering

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2023

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Vol. 24, nr 7

108--118

EN

The aim of the experiment was to assess the effects of various organic materials on Dactylis glomerata yield, on the content of selected macroelements (K, Ca and Mg) and on K:Ca, K:Mg and K:(Ca + Mg) ratios. As a valuable forage plant, Dactylis glomerata (cocksfoot grass) is a common grass in Poland both in grassland and in arable fields. Its rapid spring growth and its resistance to drought, low temperatures, but also to frequent mowing and pests, makes it a common species in meadows, pastures and grassland, both permanent and alternating. In order to achieve the research goal, a three-year pot experiment was established in a greenhouse. The experiment was conducted in a completely random design, in four replications. In the autumn before the experiment, soil was mixed with organic materials (chicken manure, mushroom substrate and rye straw) and put into pots. To selected units, an additional amount of mineral N was applied in the first year and NPK fertilizers in consecutive years. Mineral fertilizers were applied at the beginning of the growing period. Compared to control, the application of mineral and organic fertilizers resulted in a significant increase in Dactylis glomerata yield. The highest biomass yield (average over the growing periods) was recorded on the unit treated with manure, straw and mineral fertilizers (27.64 g•pot-1) and on the one with mushroom substrate applied together with rye straw and mineral fertilizers (26.47 g•pot-1). The K:(Ca+Mg) ratio in the forage was normal and averaged 0.933, but mineral fertilizers, compared to other treatments, narrowed it.

3

Impact of Spraying the Shots Parts with Ascorbic Acid on the Concentration of Some Mineral Nutrients in Vicia faba Treated with Heavy Metals

Al-Rashedy Hussein Saber Mohammed Ali, Mame Suzan Othman Omar, Alsinjari Waffaa Esam

Journal of Ecological Engineering

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2023

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Vol. 24, nr 6

1--7

EN

This study aimed examine the impact of Ascorbic acid spraying once and twice at concentrations 250 and 500 mg/L on the concentration of some nutrients in the seeds of the bean plant (Vicia faba L.) grown on soils contaminated with nickel at concentrations 30 and 60 and lead at concentrations 300, 600 mg/kg soil.The results showed that soil treated with 600 mg/kg lead has a significant decrease of concentration of magnesium, phosphorous, potassium and chloride in the seeds of the bean plants which amounted to 1.16 , 1.121, 4.113 and 0.071 mg/g, respectively compared to the control group. It was also found that spraying the vegetative parts of the bean plant with 250 mg/L ascorbic acid twice was attributed to increasing of magnesium significantly in the seeds of the bean plant, which amounted to 4.00 mg/g. otherwise, spraying with the same concentration, but once, led to a significant increase in phosphorous concentration, which reached 1.335 mg/g. The results also showed that one-time spraying of 500 mg/L ascorbic acid led to a significant increase in chloride concentration, which amounted to 0.395 mg/g compared to the control group. The results show that lead treatment had a more negative effect on the concentration of nutrients compared to the effect of nickel. It was found that spraying with ascorbic acid at a concentration of 250 mg/L was significantly superior to the concentration of 500 mg/L of magnesium, phosphorous, potassium and chloride in the seeds of bean plants. Also, spraying with ascorbic acid once was superior to spraying twice with the concentration of both magnesium and chloride.

4

Comparative performance assessment of nano-composite cathode of lmso-bscmf for low temperature solid oxide fuel cell applications

Subhashini P.V.C.K., Rajesh K.V.D.

Composites Theory and Practice

|

2023

|

R. 23, nr 4

235--238

EN

The development of novel cathode materials for low temperature solid oxide fuel cell (SOFC) applications is one of the significant research areas in materials engineering. In the current work, composite cathode materials were prepared by two different modes and the fuel cell performance was assessed using a gadolinium-doped ceria (GDC) electrolyte. Nanocomposite cathodes were fabricated using a lanthanum strontium manganite oxide (LSMO) powder of a 50-100 nm particle size and Ba0.5Sr0.5(Co0.2Mg0.8)0.2Fe0.8O3 (BSCMF) powder of a 1 μm particle size. The cathodes were prepared as layered composites and mixed composites. The electrochemical performance of the symmetric cells was investigated by electrochemical impedance spectroscopy (EIS) at the intermediate temperature of 700°C using air atmosphere. The cathode film coating on the electrolyte was sintered at three different temperatures (900, 950 and 1000°C) and the cell performance was assessed at 700°C. Lower polarization resistance (RP) values were recorded for the cell produced at 900°C. The RP of the nano-composite cathodes was measured as lower (2.72 Ω-cm2 for the layered composites and 1.76 Ω-cm2 for the mixed composites) compared with LSMO. Hence, the results demonstrate the potential of using an LSMO-BSCMF composite in the mixed mode as a cathode for low temperature SOFCs to achieve a lower polarization potential.

5

Electrochemical behavior and morphology of selected sintered samples of Mg65Zn30Ca4Pr1 alloy

Hrapkowicz Bartłomiej, Lesz Sabina, Drygała Aleksandra, Karolus Małgorzata, Gołombek Klaudiusz, Babilas Rafał, Popis Julia, Gabryś Adrian, Młynarek-Żak Katarzyna, Garbiec Dariusz

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

|

Vol. 71, nr 3

art. no. e145564

EN

In order to investigate the effect of the milling time on the corrosion resistance of the Mg65Zn30Ca4Pr1 alloy, powders of the alloy were prepared and milled for 13, 20, and 70 hours, respectively. The samples were sintered using spark plasma sintering (SPS) technology at 350◦C and pressure of 50 MPa. The samples were subjected to potentiodynamic immersion tests in Ringer’s solution at 37◦C. The obtained values of Ecorr were –1.36, –1.35, and –1.39 V, with polarization resistance Rp = 144, 189, and 101 Ω for samples milled for 13, 20 and 70 h, respectively. The samples morphology showed cracks and pits, thus signaling pitting corrosion.

6

Investigate the Metallurgical, Degradation Behavior, and Mechanical Characteristics of a Novel Magnesium Alloy

Al Khaqani Baraa H., Dawood Nawal Mohammed

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

302--312

EN

Today, the use of magnesium alloys in medical applications as a decomposing material is extensive, so a new magnesium alloy Mg-2Al-1Nd was prepared by an investment-casting method in a medium protected from atmospheric oxygen. One of the rare elements, Nd, was added to improve the microstructural and mechanical properties and corrosion resistance in simulated blood plasma media. The XRF test determined the chemical characterization elements, the SEM test was used to identify the distribution of phases and their shape inside the base before and after heat treatment, and the XRD test was conducted to determine the type of phases that formed and the effect of these phases on other properties was studied. Also, hardness was measured using Vickers microhardness, in which the improvement rate was 75%, and a compression test to determine the mechanical properties of the prepared alloy found that the modulus of elasticity was 42GPa.To study its corrosive behavior inside the human body, a test was conducted on corrosion by the Tafel method to measure corrosion resistance in simulated blood plasma solution, Where the value of the corrosion rate of the alloy after the heat treatment became 0.089mm/y and Rp equal 4.13KΩ/cm2, These results made the new magnesium alloy a good candidate for use in temporary medical applications.

7

Asymetryczne reakcje pericykliczne katalizowane kompleksami magnezu

Czombik Anna

Wiadomości Chemiczne

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2022

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[Z] 76, 9-10

755--788

EN

II Group-metals, like magnesium, are one of the most widespread elements in the environment. The abundance of II-group metals in the Earth’s crust is over 108 times greater than the precious metals. For the industrial applications, the important factors are the low costs of production and higher accessibility of their compounds. This puts the spotlight on alkaline-earth metals competing with transition elements as catalysts in organic synthesis. Features of their derivatives, like mild Lewis acidity and strong Brønsted basicity enabled them to catalyze reactions where Lewis-acidactivation of the substrate is essential. In this review the emphasis was put on magnesium-catalyzed pericyclic reactions, which are recognized as one of the most important methods of new carbon-carbon or carbon-heteroatom bonds formation. Using the catalysts based on II-group metal cations and chiral ligands, a highly stereoselective conversion of achiral substrates into enantioenriched products is possible. The Mg-based catalysts have been used in Diels-Alder, ene and 1,3-dipolar additions. Described synthesis methods were characterized by high efficiency (chemical yields and enantiomeric excesses). Where applicable, the relationships between the structure of catalyst/substrates, conditions and efficiency were discussed. Just now there are a few applications, for example in synthesis of alkaloid (–)-manzacidine or antibiotic of algal origin – (–)-malyngolide.

8

Fortyfikacja magnezem napojów funkcjonalych

Szymańska Monika, Kręgiel Dorota

Przemysł Spożywczy

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2022

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T. 76, nr 4

36--40

PL

W ostatnich 10 latach nastąpił wyraźny wzrost zainteresowania magnezem i formą jego codziennej suplementacji. To zainteresowanie ma uzasadnienie, gdyż magnez jest czwartym, pod względem zawartości, pierwiastkiem ciała człowieka, wykazującym holistyczny wpływ na funkcjonowanie całego organizmu. Niedobór magnezu może powodować nie tylko stany niepokoju, zdenerwowania, lęku, zniecierpliwienia, ale także zwiększać pobudliwość mięśnia sercowego i zaburzać procesy mineralizacji kości. Dlatego suplementacja diety magnezem poprzez lub stosowanie produktów fortyfikowanych, np. napojów funkcjonalnych, może być wygodnym sposobem uzupełnienia niedoborów tego pierwiastka w organizmie człowieka. W artykule dokonano przeglądu literatury dotyczącej magnezu i jego znaczenia dla organizmu człowieka oraz zagadnień związanych z fortyfikacją napojów funkcjonalnych.

EN

In the last decade, there has been a marked increase in interest in magnesium and its daily supplementation. This interest is justified, because magnesium is the fourth element in the human body in terms of content, showing a holistic effect on the functioning of the entire organism. Magnesium deficiency can not only cause anxiety, nervousness, anxiety and impatience, but also increase the excitability of the heart muscle and disrupt bone mineralization processes. Therefore, supplementing the diet with magnesium through or using fortified products, e.g. functional drinks, can be a convenient way to supplement the deficiencies of this element in the human body. The article reviews the literature on magnesium and its importance for the human body as well as issues related to the fortification of functional drinks.

9

Zinc and Magnesium vs COVID-19

Sokołowska Barbara, Nazaruk Stanisława Katarzyna, Radzka-Pogoda Agnieszka, Henrykowska Gabriela, Borzęcki Andrzej

Polish Hyperbaric Research

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2022

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nr 2(79)

45--52

EN

Zinc and magnesium are among the most important elements for the human body. A deficiency or excess of either of them may pose a potential threat to the homeostatic mechanisms of the body. Both elements condition the proper functioning of the immune system. Zinc and magnesium deficiency significantly reduces the body's immunity, facilitating infection with various pathogens, including SARS-COV-2 infection. In this paper, we reviewed the literature on the impact of zinc and magnesium deficiencies on the incidence and course of COVID-19.

PL

Cynk i magnez to jedne z ważniejszych pierwiastków dla organizmu człowieka. Niedobór lub nadmiar któregoś z nich może stanowić potencjalne zagrożenie dla mechanizmów homeostazy ustroju. Pierwiastki te warunkują prawidłowe funkcjonowanie układu immunologicznego. Niedobór cynku i magnezu istotnie zmniejsza odporność organizmu ułatwiając infekcje różnymi patogenami, w tym zakażenia SARS-COV-2. W pracy dokonano przeglądu piśmiennictwa obejmującego zagadnienia wpływu niedoborów cynku i magnezu na zachorowanie i przebieg COVID-19.

10

An Analysis of the Features of Cast Composite Materials Based on Light Alloys Reinforced by Particles

Dan Olena

Journal of Casting & Materials Engineering

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2022

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Vol. 6, no. 1

8--13

EN

Light alloys are widely used in industry and everyday life due to their high physical and mechanical properties, wear and corrosion resistance, as well as low cost. In this regard, the use of light alloys as a basis for composite materials is both justified and expedient. The potential of these materials has not been fully used to this day, despite the growing interest in metal matrix composites and extensive investigations aimed at the development of production technology and the introduction of advanced systems based on light matrices. The article presents a short review of the analysis of the main components of the technology of cast composite materials based on light alloys of aluminum and magnesium reinforced by particles. Particular attention is paid to the choice of the matrix alloy, the type, size and amount of reinforcing particles introduced into it, as well as the thermal-time and kinetic parameters of the process.

11

The role of β (Al12Mg17) phase on corrosion behavior of the AM90 alloy in NaCl aqueous solution

Hatakeyama Masahiko, Shimada Yusuke, Kawate Naoki, Sarayama Kaede, Sunada Satoshi

Archives of Metallurgy and Materials

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2022

|

Vol. 67, iss. 2

759--766

EN

The β phase (Al12Mg17) precipitated by heat treatment in some alloy compositions may result deterioration of corrosion resistance. However, much of its role remains unclear. The effect of the β phase on the corrosion resistance behavior in a NaCl solution was presented in this study. The specimen was Mg-9mass%Al (AM90) alloy and the content of the β phase precipitant was controlled systematically by aging time at 473 K. Area rate of β and lamellar phase in the specimens were 0, 10 and 100%, respectively. According to the results of cathodic polarization curves measurement, the corrosion current density of α phase was 0.215 A/m2 and β phase of it was 0.096 A/m2. While, the specimen includes 10% of β and lamellar phase showed large corrosion current density of 0.251 A/m2. Positive correlation between the β phase and the open circuit potential, suggest that the β phase acts as a cathodic electrode. Moreover, the microstructure after postentiostatic corrosion tests was also support the role of β phase.

12

A comparative Study on the Mechanical and Corrosion Properties of the ZM20 and ZM21 Alloys after Casting and Rolling

Gören Halil Ahmet, Ünal Mehmet, Türen Yunus, Ahlatçı Hayrettin, Sun Yavuz

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1387--1394

EN

In this study, the effects of grain refinement and production methods on the corrosion, corrosive wear and mechanical properties of the as-cast and as-rolled Mg-2 wt.% Zn (ZM20) and Mg-2 wt.% Zn-0,51 wt.% Mn (ZM21) alloys were examined by using OM, XRD, SEM, hardness and uniaxial tensile test. Additionally, the potentiodynamic polarization, immersion corrosion test and corrosive wear properties of the ZM20 and ZM21 alloys were compared. According to the XRD results, MgZn and MgZn2 phases were found in the alloys and also MnZn3 phase occurred in the ZM21 alloy with the addition of manganese. Both during solidification forming nucleation points with the added manganese and during rolling the broken secondary phase particles distributed into the matrix prevented grain growth and led to the formation of a more refined structure. The tensile test results showed that the strength of the as-cast ZM21 alloys were better than that of the as-cast ZM20 alloys and further improvement in mechanical properties occurred with the rolling of the both alloys. The most superior hardness was found in the as-rolled ZM21 alloy. In the total 400-m reciprocal corrosive wear test in the 3.5% NaCl solution, the lowest mass loss was in the as-rolled ZM21 alloys. In the potentiodynamic corrosion test, the highest corrosion resistance was occurred by the as-cast ZM20 alloy.

13

Znaczenie alotropii wybranych pierwiastków chemicznych oraz polimorfizmu ich związków

Badora Aleksandra, Celińska Magdalena, Filipek Tadeusz

Przemysł Chemiczny

|

2021

|

T. 100, nr 2

168--172

PL

Wiele pierwiastków chemicznych oraz ich związków ma szerokie zastosowanie w produktach dostępnych na rynku. Są obecne zarówno w produktach żywnościowych, preparatach leczniczych, jak i w kosmetykach. Na podstawie przeglądu literatury i danych producenta dokonano analizy ich aktywności oraz potencjalnych korzyści i zagrożeń wynikających z ich stosowania. Przeanalizowano też wpływ tych substancji na środowisko naturalne.

EN

A review, with 35 refs., of chem. elements and their comps. used in foods, drugs and cosmetics. Their activity, potential benefits and risks as well as environmental impacts were taken into consideration.

14

Synthesis of Mg-based alloys with rare-earth element addition by means of mechanical alloying

Lesz Sabina, Hrapkowicz Bartłomiej, Gołombek Klaudiusz, Karolus Małgorzata, Janiak Patrycja

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

|

Vol. 69, nr 5

art. no. e137586

EN

Magnesium-based alloys are widely used in the construction, automotive, aviation and medical industries. There are many parameters that can be modified during their synthesis in order to obtain an alloy with the desired microstructure and advantageous properties. Modifications to the chemical composition and parameters of the synthesis process are of key importance. In this work, an Mg-based alloy with a rare-earth element addition was synthesized by means of mechanical alloying (MA). The aim of this work was to study the effect of milling times on the Mg-based alloy with a rare-earth addition on its structure and microhardness. A powder mixture of pure elements was milled in a SPEX 8000D high energy shaker ball mill under an argon atmosphere using a stainless steel container and balls. The sample was mechanically alloyed at the following milling times: 3, 5, 8 and 13 h, with 0.5 h interruptions. The microstructure and hardness of samples were investigated. The Mg-based powder alloy was examined by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and using a Vickers microhardness test. The results showed that microhardness of the sample milled for 13 h was higher than that of those with milling time of 3, 5 and 8 h.

15

Mechanical alloying of Mg-Zn-Ca-Er alloy

Hrapkowicz Bartłomiej, Lesz Sabina, Kremzer Marek, Karolus Małgorzata, Pakieła Wojciech

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2021

|

Vol. 69, nr 5

art. no. e137587

EN

Magnesium-based materials constitute promising alternatives for medical applications, due to their characteristics, such as good mechanical and biological properties. This opens many possibilities for biodegradable materials to be used as less-invasive options for treatment. Degradation is prompted by their chemical composition and microstructure. Both those aspects can be finely adjusted by means of proper manufacturing processes, such as mechanical alloying (MA). Furthermore, MA allows for alloying elements that would normally be really hard to mix due to their very different properties. Magnesium usually needs various alloying elements, which can further increase its characteristics. Alloying magnesium with rare earth elements is considered to greatly improve the aforementioned properties. Due to that fact, erbium was used as one of the alloying elements, alongside zinc and calcium, to obtain an Mg₆₄Zn₃₀Ca₄Er₁ alloy via mechanical alloying. The alloy was milled in the SPEX 8000 Dual Mixer/Mill high energy mill under an argon atmosphere for 8, 13, and 20 hours. It was assessed using X-ray diffraction, energy dispersive spectroscopy and granulometric analysis as well as by studying its hardness. The hardness values reached 232, 250, and 302 HV, respectively, which is closely related to their particle size. Average particle sizes were 15, 16, and 17 μm, respectively.

16

Production of High-Purity Tantalum Metal Powder for Capacitors Using Self-Propagating High-Temperature Synthesis

Lee Yong-Kwan, Sim Jae-Jin, Byeon Jong-Soo, Lee Yong-Tak, Cho Yeong-Woo, Kim Hyun-Chul, Heo Sung-Gue, Lee Kee-Ahn, Seo Seok-Jun, Park Kyoung-Tae

Archives of Metallurgy and Materials

|

2021

|

Vol. 66, iss. 4

935--939

EN

In this study, high-purity tantalum metal powder was manufactured via self-propagating high-temperature synthesis. During the process, Ta2O5 and Mg were used as the raw material powder and the reducing agent, respectively, and given that combustion rate and reaction temperature are important factors that influence the success of this process, these factors were controlled by adding an excessive mass of the reducing agent (Mg) i.e., above the chemical equivalent, rather than by using a separate diluent. It was confirmed that Ta metal powder manufactured after the process was ultimately manufactured 99.98% high purity Ta metal powder with 0.5 μm particle size. Thus, it was observed that adding the reducing reagent in excess favored the manufacture of high-purity Ta powder that can be applied in capacitors.

17

Hydrogeological Assessment of the Mineral Composition of the Bottled Waters Available For Sale in Poland

Porowska Dorota

Journal of Ecological Engineering

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2020

|

Vol. 21, nr 4

103--111

EN

The choice of bottled waters available for sale is large. The assessment of their mineral composition was based on the results of 120 natural waters and 46 mineral waters (in relation to the hydrogeological classification of water mineralization). Significant diversity was found in terms of the basic mineral composition, and in many cases also a wealth of microcompounds (e.g. fluorides, iodine, selenium), which have a positive effect on the human health. Both the deficiency and excess of the water consumed and the amount of contained ingredients have an influence on the human health. While choosing water, it is worth considering the volume of water consumed, the age and health of the consumer, season of year, activity, type of diet, taken dietary supplements, vitamins and medicines. The information on the label is sufficient to choose the water suited to the individual needs. The waters with high mineralization and/or with large concentrations of microcompounds should be used after medical consultations to determine their use: specify the area of application and recommended drinking amount and frequency.

18

The role of hydrogen gas buble in hydrophobic properties in mixed micro layer (Al2O3+Mg)

Subagyo R., Wardana I. N. G., Widodo A., Siswanto E.

Archives of Materials Science and Engineering

|

2020

|

Vol. 105, nr 1

5--16

EN

Purpose: To find out more about the role of hydrogen gas bubbles in improving the hydrophobic nature of a layer, especially in the layers of microparticles Alumina (Al2O3) with Magnesium (Mg). Design/methodology/approach: The method used is an experimental method by first conducting the SEM-Edx test, testing the content of the elements in the waxy layer and observing the topographic shape on the surface of the taro leaves. Then prepare a mixture of Alumina micro particles with Magnesium to investigate the hydrophobicity of the taro leaves. The mixed presentations between Alumina and Magnesium are: (0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100%). Findings: The results of this study found three conditions of the Alumina and Magnesium mix layer when in contact with a droplet, namely: Hydrophobic conditions occur when the surface structure of the rough mixed micro layer forms micro crevices, then bubbles of hydrogen gas fill it to form trapped gases. When droplets come in contact with the surface of the mixed layer the effect of the gas being trapped is very effective at creating hydrophobic properties. While the transition conditions occur when more and more hydrogen gas bubbles along with the increasing percentage of Mg and the opposite occurs in micro particle fissures. Bubbles fill the micro-gap space fully so that the tops of the micro particles are covered by bubbles. This causes the droplet surface tension to weaken, so the droplet contact angle decreases. Furthermore, hydrophilic conditions occur when the micro gap is getting narrower as the percentage of Mg increases and the formation of hydrogen gas bubbles increases. The high level of bubble density in the micro gap closes the peaks of the micro particles, which results in the surface tension of the droplet getting weaker. In this weak surface tension condition, the hydrogen bubble can break through the droplet surface tension and change its hydrophobic nature to hydrophilic. Research limitations/implications: This research is limited to the hydrophobicity of Alumina and Magnesium materials, mainly to investigate the role of hydrogen gas in supporting the hydrophobic nature of taro leaves (Colocasia esculenta). Practical implications: The practical implication in this study is the use of hydrophobic membranes which are widely applied to filtration. Originality/value: Discovered the composition of a membrane mixture of Alumina (Al2O3) and Magnesium (Mg) to create hydrophilic and hydrophobic conditions.

19

Investigation on Reactions at Corners of Cast Part during Investment Casting of Reactive AZ91 Magnesium Alloy

Vyas Akash V., Sutaria Mayur .

Archives of Foundry Engineering

|

2020

|

Vol. 20, iss. 4

139--144

EN

The magnesium alloy investment castings have greater potential for automobile and air-craft applications due to the higher strength to weight ratio of magnesium alloys and capability of the investment casting process to produce near net shape complex castings. The interfacial-mould metal reactions during investment casting of magnesium alloy inhibit successful production of quality castings. This paper presents the investigation done on the reactions at corners of AZ91 magnesium alloy cast part produced through investment casting. The stepped shape geometry of casting was selected to study the reactions at convex and concave corners of the cast part. The reacted surfaces were characterised using the SEM-EDX and XRD. The formation of oxides was observed on cast surface from characterisation. The temperature profile recorded at corners were helpful to understand the heat dissipation during the solidification of metal at corners. It was observed that the reactions occurred at the concave corner were more as compared to the convex corner of the cast part.

20

Analysis of the nitrogen and magnesium doses effects of two cultivars of maize (Zea mays L.) using multivariate methods

Bocianowski Jan, Cichocki Marek, Szulc Piotr, Tratwal Anna, Nowosad Kamila, Kobus-Cisowska Joanna

Journal of Research and Applications in Agricultural Engineering

|

2019

|

Vol. 64, nr 3

4--9

EN

The paper presents the results of a multivariable research regarding the evaluation of variability of selected quantitative traits in two cultivars of maize (Zea mays L.): ES Palazzo and ES Paroli after using doses of nitrogen and magnesium. The study took into account 12 traits recorded for three years (2009-2011). The statistical analysis of obtained results was conducted using multivariable methods: multivariate analysis of variance, canonical variable analysis and Mahalanobis distances. The most varied objects were A4B1C2 and A1B2C1 (in 2009), A4B1C1 and A2B2C2 (in 2010), A4B2C1 and A1B2C2 (in 2011) and A4B2C1 and A1B2C2 (for all three years). The most similar objects (with regard to the 12 traits analyzed together) were A4B2C2 and A3B2C2 (in 2009), A4B2C2 and A3B1C2 (in 2010), A2B2C2 and A2B1C2 (in 2011) and A4B2C2 and A3B2C2 (for all three years). The Mahalanobis distances between particular objects in particular years of observations were positive and statistically significantly correlated.

PL

W pracy przedstawiono wyniki badania zmienności wybranych cech ilościowych dwóch odmian kukurydzy (Zea mays L.): ES Palazzo i ES Paroli po zastosowaniu różnych dawek azotu i magnezu stosując wielowymiarowe metody statystyczne. W badaniach wzięto pod uwagę 12 cech ilościowych obserwowanych w doświadczeniu trzyletnim przeprowadzonym w latach 2009-2011. Analiza statystyczna uzyskanych wyników została przeprowadzona z użyciem metod wielowymiarowych: wielozmiennej analizy wariancji, analizy zmiennych kanonicznych i odległości Mahalanobisa. Najbardziej zróżnicowanymi obiektami były A4B1C2 i A1B2C1 (w 2009), A4B1C1 i A2B2C2 (w 2010), A4B2C1 i A1B2C2 (w 2011) oraz A4B2C1 i A1B2C2 (dla wszystkich trzech lat). Natomiast, najbardziej podobnymi obiektami (pod względem wszystkich 12 cech traktowanych łącznie) były A4B2C2 i A3B2C2 (w 2009), A4B2C2 i A3B1C2 (w 2010), A2B2C2 i A2B1C2 (w 2011) oraz A4B2C2 i A3B2C2 (dla trzech lat). Odległości Mahalanobisa pomiędzy poszczególnymi obiektami w poszczególnych latach prowadzenia obserwacji były dodatnio i istotnie statystycznie skorelowane. Słowa