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Content available remote Manufacturing Cu-Pb alloys and studying efficiency in resisting oxidation
EN
Binary alloys of copper and lead were produced by casting these elements in specially designed moulds with dimensions appropriate to the tests to be carried out on them. The effectiveness of these alloys in resisting oxidation was then studied in an atmosphere of a mixture of sodium chloride vapour and sodium sulphate at specific concentrations and heating the mixture to 180°C. Recently, corrosion has become a major problem in the overall performance of many engineering devices due to automotive exhaust gases produced by the internal combustion engine, which leads to corrosion of materials that make up some components of engineering industries. Copper also has good corrosion performance due to the formation of a copper oxide layer, which has made it the most important material in industrial applications. Through this research, we have achieved the desired goal as the alloys produced have shown their efficiency in resisting saline and acidic conditions and at high levels. The best sample is Cu95Pb5 and Cu90Pb10 with little difference between them in terms of efficiency. The aim of this work is to produce alloys and study their efficiency in resisting oxidation at high temperatures.
PL
Binarne stopy miedzi i ołowiu zostały wytworzone metodą odlewania w specjalnie zaprojektowanych formach o wymiarach dostosowanych do badań. Odporność stopów na utlenianie została zbadana w atmosferze mieszaniny oparów chlorku sodu i siarczanu sodu w określonych stężeniach i po podgrzaniu mieszaniny do 180°C. Korozja jest poważnym problemem, zaburza funkcjonowanie wielu urządzeń inżynieryjnych. Jej źródłem są m.in. spaliny wytwarzane przez silniki spalinowe. Miedź ma dobre właściwości antykorozyjne ze względu na warstwę tlenku miedzi, tworzącą się na jej powierzchni w wyniku utleniania. Z tego względu jest głównym materiałem stosowanym w przemyśle. Badane stopy miedzi i ołowiu wykazały wysoką odporność na działanie soli i kwasów w dużych stężeniach. Najlepsze wyniki uzyskano dla stopów Cu95Pb5 i Cu90Pb10 (różnica między nimi była niewielka). Celem pracy było zbadanie odporności wytworzonych stopów na utlenianie w wysokich temperaturach.
EN
Among a number of climate-related factors, moisture has the greatest impact on crop productivity. In recent years, certain changes have been observed under conditions of the Forest-Steppe of Ukraine with regard to precipitation – from low to in some cases – abnormally high, which requires the study of their impact on the yield and safety of cereal grain for its forecasted production. The article examined the effect of a high level of soil moisture (256.2–272.5 mm) and a low level (47.4–52.3 mm) during the growing season (germination→earing) of spring barley grain on the accumulation of heavy metals in it and its productivity under the conditions of gray forest soils of the Right Bank Forest Steppe of Ukraine. Spring barley varieties Helios and Caesar were selected for the research. A decrease in the accumulation coefficient at a high level of soil moisture (256.6–272.5 mm) in spring barley grain Pb from 8.3% to 11.3%, Cd – from 35.0% to 35.5%, Zn was established – by 15% and Cu – from 11.2% to 16.6% compared to the low level of soil moisture (47.1 mm – 53.3 mm). At the same time, it was found that with a high level of soil moisture, there is a decrease in the yield of Helios and Caesar spring barley by 18.0% and 14.1%, respectively.
EN
The potential of Georgian natural Mordenite has been studied as a low-cost, eco-friendly adsorbent for the removal of lead (II) ions from aqueous solutions in various experimental environments. The natural and modified Mordenite structural characterization was carried out using XRD, SEM-EDS, XRF, methods. The following parameters were studied for adsorption: dependence of solution pH, adsorbent dose, and initial concentration of lead (II) ions. The results of the optimization study showed that a high dose of adsorbent and a low concentration of Pb (II) ion increase the sorption. The optimum pH was found to be 6-8. Sorption capacity increased along with pH. Langmuir and Freundlich isotherms were used to model the adsorption data. Correlation coefficient values (R2) were 0.975 and 0.922, respectively. Isotherm studies showed that the uptake equilibrium is best described by the Langmuir adsorption isotherm. The maximum sorption capacity was found to be 11.439 mg/g. The research results showed that natural Georgian Mordenite can be used to remove Pb (II) ions from aqueous solutions.
EN
Plants are constantly exposed to a variety of stressors during their lives. One of such stressors is contamination of the environment with heavy metals. Lead is one of highly toxic metals and it significantly inhibits normal plant growth. The study aimed at assessing the degree of relieving the stress caused by 1 mM Pb(NO3)2 via different biologically active substances (AsA, GSH, PP, α-Toc, SA) on the basis of the measurement of morphological (root length, coleoptile length, fresh weight), biochemical (Pro, MDA, CAT, POX) and physiological (Chl a+b, Car) traits in 10-day leaves of spring barley of the cultivar Eunova under laboratory conditions. Pb-stress reduced the fresh weight, root length and coleoptiles of the barley tested. Lead increased lipid peroxidation and Pro content, enhanced CAT and POX activity, and significantly suppressed the photosynthetic pigments content. Among the substances used in the experiment, PP, α-Toc and GSH generally relieved the toxic effect of lead to the barley seedlings to the greatest degree.
EN
The aim of the research was to evaluate the effectiveness of the removal of Cu and Pb ions by algae. The experiments were carried out in the presence of two algal populations: a pure culture of Raphidocelis subcapitata, and a mixed chlorophyta population. The research involved a model study, experiments in the presence of wastewater from the manufacture of batteries, and the study of process kinetics. The wastewater pH was 4.0, and the initial concentrations of metal ions in the wastewater were 95.4 mg/L for Pb and 48.3 mg/L for Cu, respectively. The maximum sorption capacity of the pure Raphidocelis subcapitata culture was 14.8 mg/g d.m. for Pb, corresponding to the removal of 72% of lead, and 6.1 mg/g d.m. for Cu, corresponding to the removal of 43% of copper from the wastewater. The best ion sorption efficiency in the case of the mixed chlorophyta population was 7.0 mg/g d.m. for Pb, i.e., 61% removal of lead, and 12.8 mg/g d.m. for Cu, i.e., 69% removal of copper ions from the wastewater. The optimum duration of the process was found to be 1 hour, since the majority of biomass samples reached the maximum saturation after that time. On the basis of the obtained results (Lagergren models), it was found that the dominant mechanism of the process was chemisorption.
EN
This research aimed to determine the effect of different concentrations of Lead (Pb) on the morphology of kale and spinach plants. The process involved planting kale and spinach seeds in tubs and transferring them to polybags with planting media in the form of soil and sand at a ratio of 4:1 after strong roots were developed. It is important to note that the media were analyzed to ensure the Pb content in the soil was below the threshold before planting. Pb was later provided 1 week before planting in the form of PbNO3 in the media at a dose of 1 and 2 g/polybag and mixed effectively to ensure even distribution, while the sample used as the control was not given any Pb. The transplanting process was conducted after the plants were 18 days old in the nursery and the initial observations at 9 DAT showed that the kale leaves were darker with a score of 3 than spinach with a score of 1, but the spinach leaves became darker in color with score 3 as the age of the plants increased. Moreover, the kale changed to a lighter color with a score of 2 from the 9th day of observation after transplanting, while spinach requires 15 DAT to become score 2 until the end of the observation. It should be pointed out that both plants showed morphological changes due to the existence of the Pb but their base leaves did not reflect any effect. The kale leaf tip became blunt, while the spinach leaf tip was not affected and both plants were discovered to have longer roots and more root hairs in the control compared to the treatments. Furthermore, the total chlorophyll of spinach in the control was higher than kale but observed to reduce as the concentration of Pb increased in the treatments. The morphology and physiology of spinach and kale plants changed due to the Pb exposure with the spinach was discovered to be more sensitive as indicated by more visible morphological damage to its leaves at the end of the observation. It is possible to use the morphology of spinach and kale to detect Pb-contaminated land.
EN
Phytoremediation is the technique of using green plants to remove toxic pollutants from heavy metal contaminated soil through degradation and detoxification mechanisms. Therefore, this research examines the potential of two types of vegetable crops, namely Crassocephalum crepidioides and Amaranthus sp., in reducing Pb contamination in polluted soil. The treatments tested were planting media in polybags dosed with 0.3 and 6 g/polybag of Pb 1 week before planting. The method used was a randomized block design, with each treatment being repeated three times. Furthermore, each treatment consists of three sample plants. The growth evaluation started 6 days after planting and was performed every 6 days. The evaluation was conducted on plant height, leaf area, leaf chlorophyll content, fresh and dry weight of roots and shoots, Pb levels in roots and shoots, and Translocation Factor (TF). The results showed that the higher the Pb in the media, the lower the rate of change in plant height, leaf area, biomass, and chlorophyll content. Additionally, C. crepidioides and Amaranthussp. absorb Pb in the soil with a phytoextraction mechanism, thereby remediating heavy metal contaminated soil, as indicated by the TF value > 1. In conclusion,soil remediation should be performed using C. crepidioides, considering that it is less popular as a vegetable in Indonesia.
EN
The study presents the possibility of using chlorophyta in the removal of cadmium and lead ions from industrial wastewater produced after the washing of equipment used in the manufacture of battery and batteries. The process was conducted with the use of two algal cultures: Raphidocelis subcapitata produced in laboratory conditions, and a mixed chlorophyta population collected from a natural, eutrophicated water reservoir with heavy metal ions present in the water and sludge. The study showed that the effectiveness of a pure algal culture is comparable to that of a mixed chlorophyta population, characterized by greater diversity of functional groups at binding sites and higher resistance to stress that may occur in the wastewater environment. The maximum effectiveness of ions sorption was 64% for cadmium (mixed algal population) and 60% for lead (Raphidocelis subcapitata).
EN
The present study aims at the development of a green sorbent (MgAl-LDH-biochar) from the municipal solid wastes (cow bones) to remediate water from heavy metals. MgAl-LDH-biochar was characterized using X-ray diffraction (XRD), and it was used to remove lead at different pH, doses, contact time (Ct), and solution temperatures (St). The obtained results proved MgAl-LDH-biochar removes 99% of lead when the initial pH, Ct, St, and dose were 5.0, 80 min, 45°C, and 0.2 g·L–1, respectively.
PL
W artykule przeprowadzono analizy gleb na terenach strzelnic otwartych pod względem zanieczyszczeń w postaci wybranych metali ciężkich. Badane próbki pochodziły z wyłączonych z eksploatacji strzelnic zlokalizowanych na terenach gminy Włocławek. W toku badań zrealizowano oznaczenia zawartości następujących pierwiastków: Zn, Pb, Cd, Cu, Ni, Co, Fe, As. Dokonano również charakterystyki badanych lokalizacji oraz oceny pobranych próbek gleb zgodnie z Rozporządzeniem Ministra Środowiska z dnia 1 września 2016 r. w sprawie sposobu prowadzenia oceny zanieczyszczenia powierzchni ziemi. Badania potwierdzają zależność zachodzącą pomiędzy oddziaływaniem prowadzonych zajęć strzeleckich, a stopniem akumulacji wybranych pierwiastków metali ciężkich w glebie otwartych strzelnic. Oznaczenia dowodzą, że stanowi to niekiedy bardzo złożone zagadnienie, które zbagatelizowane może w przyszłości spowodować poważne zagrożenie.
EN
The paper describes analyses of soils taken from open shooting ranges to find pollutants in the form of selected heavy metals. Test samples were taken from closed shooting ranges located in Wloclawek commune. During the investigations the content of following elements was identified: Zn, Pb, Cd, Cu, Ni, Co, Fe, As. The characterization of investigated localizations was also made with evaluation of samples of soils according to the Regulation of the Minister of Environment from 01 September, 2016 on the assessment of ground surface pollution. Studies confirm the relationship occurring between the effects of carried out shooting activities and the degree of accumulation of selected heavy metals elements in the soil of open shooting ranges. Indications show that this is sometimes a very complex issue and if neglected it can cause in the future a serious threat.
EN
The research study investigated the biosorption behavior of Pb(II) ions by treated and untreated biomass of B. subtilis. At initial biosorption conditions, the biosorption efficiency was found to be 36.75%. At the optimized experimental conditions, control biomass showed maximum biosorption efficiency of 58.04% where the biomass was treated with different chemicals. The biomass treated with formaldehyde showed the highest efficiency of 80.9% which was further optimized and attained maximum efficiency of 89.8% for Pb(II) ions. SEM (Scanning Electron Microscope) and EDX (Energy dispersive X- ray) analysis evaluates the structural and elemental changes that occurred as a result of biosorption. Functional groups that are involved in biosorption were revealed by FTIR (Fourier Transform Infrared spectroscopy). Kinetic data showed the best fit with the pseudo second-order model. Effective removal of lead ions from industrial contaminated water sources by pretreatment biomass of B. subtilis elucidates its potential use as biosorbent for metal remediation.
EN
Demand for raw materials is increasing exponentially. To satisfy that demand, more minerals need to be mined from the Earth's crust. As a result, minerals are being exhausted, and ore grades decline. Lower ore grade mines also mean more energy, which in turn entails fossil fuel emissions and more climate change. This paper estimates the specific energy for the beneficiation process of metals lead and zinc as case studies. The evaluation is performed with specialized software, HSC Chemistry which assesses the specific energy for every stage: comminution, flotation, and refining. Different scenarios have been established to simulate the behavior of a mine when it approaches depletion. Preliminary results show that energy consumption for lead would increase by five times when compared to the current situation if ore grades decrease until the level of tailings, while for zinc by almost two.
EN
Lead (Pb) is a heavy metal often discovered to be polluting the water areas. One of the efforts made to overcome the heavy metal pollution in estuaries was phytoremediation technique using mangroves. The Wonorejo River was one of the rivers that received industrial waste loads. There were various types of mangrove plant species at the estuary of the Wonorejo River. The location of this research was divided into 3 monitoring stations (A, B, C). Station A was directly adjacent to the estuary, as location C was farther away and very close to the sea. However, station B was located between location A and B. This study aimed to determine the ability of mangrove in remediating and illustrating the distribution of Pb, at the Wonorejo River estuary. Moreover, it also aimed to determine the values of Bioconcentration (BCF) and Translocation (TF) Factors in the ability of Avicennia alba, Avicennia marina, Sonneratia caseolaris, Avicennia lanata, and Rhizophora stylosa to accumulate Pb. The samples were the roots, stems, and leaves of mangroves, with the water and sediment at the Wonorejo estuary, as all solid materials were also extracted. The samples were analyzed for heavy metal concentration, using an atomic absorption spectrophotometer (AAS). The results showed that the highest average Pb concentration for waters and sediments was obtained at station C and A, with values of 0.069 mg/L and 4.22 mg/kg, respectively. It was further observed that the Pb concentration in the water was lower than in sediment, indicating that the metal was accumulated in the sediments. On the basis of the BCF value, the most effective mangrove involved in the accumulation of Pb was A. alba. The highest values of TF for both root to stems and to leaves in the accumulation of Pb was also discovered in A. lanata and A. alba mangroves, respectively. On the basis of the Pb distribution mapping, the concentration of the metal was shown to increased, as the research location moved further away from the estuary. Conclusively, each type of mangrove had different ability to accumulate and translocate Pb in its body, with the potential of using those plants as phytoremediaton agents for the metal.
EN
The heavy metal pollution in seawater and sediment can damage mangrove ecosystems and accumulate in mudskipper (Periophthalmus spp.) that lives in mangrove forests. The accumulation of heavy metal in mudskipper can affect the structure of its gill tissue, liver, and muscles. This research aims at (1) analyzing the levels of lead, cadmium and cuprum heavy metals in mudskipper, sediment, and seawater and (2) analyzing the damage to the gill, liver, and muscle tissue of mudskipper due to the exposure to heavy metals. The mudskipper samples were collected from the mangrove forests of Poka, Waai, and Rutong from May to June in 2019. The heavy metal analysis was conducted using the AAS method, while the gill, liver and muscle tissue staining was carried out with the HE (Hematoxylin Eosin) staining method with 40x magnification. The data were analyzed using descriptive analysis and correlational analysis. The results of the analysis showed that based on the mangrove locations, the order of Pb and Cu accumulation in mudskipper was Rutong> Poka> Waai; while the order of the Cd accumulation was Rutong> Waai> Poka. The changes in the gill tissue structure due to the exposure to heavy metals were in the form of teleangiectasia, secondary lamellar edema, hyperplasia, epithelial desquamation, clubbing, and primary lamellar edema. The changes in the liver tissue structure due to the exposure to heavy metals involved hemorrhage and fat degeneration. The changes in the muscle tissue structure due to the exposure to heavy metals include changes in muscle fibers, edema, and necrosis. The highest accumulation of Pb and Cd was found in gills and muscles from seawater, while low level of heavy metal Cu was found in the liver.
EN
Eco-friendly saponin from soapnut was studied for the remediation of the soils contaminated by lead. This study applied a full factorial design of the experiment with 3-factors in 3-level (3×3 factors) to evaluate the effect and interactions of the washing parameters on the lead removal by soapnut in a batch experiment. The parameters studied include: soil-solution ratio, surfactant concentrations by mass, and pH of the washing solution. Two soil samples representing low lead concentration (C1) and high lead concentration (C2) were investigated. The findings indicate that the removal efficiency obtained, increases along with the soil-solution ratio and surfactant concentration, but decreases with an increase in the pH of washing solution. Polynomial models were developed to predict the experimental response and optimal conditions. The model predicted a maximum of 50.54% and 47.44% lead removal from the contaminated soil C1 and C2, respectively. Multiple washing was investigated using the higher values of the parameters; the responses obtained significantly increased the percentage of lead removed and achieved 79.98% removal for C1 and 77.49% removal for C2. The effective performance of the soil washing process demonstrates the potential usage of soapnut saponin in the remediation of contaminated soil. Saponin from soapnut is cheap and environment-friendly.
EN
The continuous system of lead adsorption on rice husks was investigated in this paper. A fixed bed study was performed in many tests to investigate the influence of pH, the adsorbent height, the initial concentration of lead, the flow rate and processing time on the lead adsorption process. The results demonstrated that the lead removal capacity decreased when the pH value of the solution and the flow rate increased. The lead removal capacity increased due to the decreased initial concentration of lead. The results showed that the removal capacity increases along with the processing time and the adsorbent height in column. The largest removal was (81%) at pH of 4, the adsorbent height (50 cm), the initial concentration of lead (10 mg/l), the processing time (90 min.) and the flow rate (10 ml/min.). As a result, rice husks can be used to remove the lead instead of expensive commercial adsorbents, due to its availability, inexpensive and perfect adsorption property.
EN
Paronchia argentea is traditionally being used for medicinal purposes in Jordan. The current investigation was designed to check the in vitro efficacy of in vitro and ex vitro P. argentea against selected bacterial and fungal strains. The antimicrobial properties of in vitro plantlets and field (ex vitro) plant extracts of P. argentea were investigated against both bacteria and fungi, after and before heavy metals stress used. In this study, four bacterial species were used: Listeria monocytogen and Staphylococcus aureus (Gram positive bacteria) Salmonella typhimurum and Coronobacter sakazakii (Gram negative bacteria) and Calvularia lunata as a mold. The obtained results revealed that the in vitro grown plantlets with the supplemented of lead (Pb), copper (Cu) or Cobalt (Co) with methanol and aqueous extract showed significant inhibitory activities within zones of inhibition ranging between 6.7-30.0 mm. All extracts of P. argentea had activity against the fungi and bacteria tested. The maximum inhibition zone was found in Staphylococcus aureus (30 mm inhibition zone) in medium supplemented with 0.3 mg/L Cu followed by Calvularia lunata (30.0 mm inhibition zone). The methanolic and aqueous P. argentea extract indicate that the solvent plays an important role in the solubility of the antimicrobial substance and also affects the activity of the microbe. Both field (ex vitro) and tissue culture plant extract showed similar antimicrobial activity. The present study could be used as an approach for the development of new, alternative and cheap antimicrobial drugs, particularly against the infections caused by the tested microbes through the tissue culture technology.
EN
Lead and zinc are heavy metals with toxic properties. These chemical elements are found in wastewater. The article deals with the removal of lead(II) and zinc(II) ions from polluted water using adsorption. As object of researches was selected natural polymer - fibber hemp (Cannabis sativa L.). Big quantities of fibber hemp are produced as waste in textile, agricultural industry, and therefore their usage could help to solve two problems - reducing quantity of fibber hemp as waste and reducing of water pollution by heavy metals. Pb(II) and Zn(II) ions adsorption with fibber hemp was investigated for contact time, pH, and heavy metal ions concentration impact. Pb(II) and Zn(II) ions biosorption rate was highest within the first hour, with optimal their biosorption recorded at pH = 5.0. Highest lead and zinc ions removal efficiency was recorded after 240-480 min and reached 60.5 and 61.7 % respectively. This study demonstrated the applicability and effectiveness of fibber hemp in lead and zinc ions removal, which could be applied for the sewage treatment plant in small scale.
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