scholarly journals Heavy Metals Nanofiltration Using Nanotube and Electric Field by Molecular Dynamics

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Tiago da Silva Arouche ◽  
Rosely Maria dos Santos Cavaleiro ◽  
Phelipe Seiichi Martins Tanoue ◽  
Tais Sousa de Sa Pereira ◽  
Tarciso Andrade Filho ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Boron Nitride ◽  
Electric Field ◽  
Metal Ions ◽  
External Electric Field ◽  
Ion Selectivity ◽  
Intermolecular Forces ◽  
Water Molecules ◽  
The Impact

Heavy metal contamination in the world is increasing the impact on the environment and human life. Currently, carbon nanotubes and boron are some possible ideals for the nanofiltration of heavy metals due to the property of ion selectivity, optimized by the applications of the surface and the application of an external electric field. In this work, molecular dynamic was used to transport water with heavy metals under the force exerted by the electric field action inside nanotubes. This external electric field generates a propelling electrical force to expel only water molecules and retain ions. These metal ions were retained to pass through only water molecules, under constant temperature and pressure, for a time of 100 ps under the action of electric fields with values from 10-8 to 10-1 au. Each of the metallic contaminants evaluated (Pb2+, Cd2+, Fe2+, Zn2+, Hg2+) was subjected to molecular test simulations in the water. It was found that the measurement of the intensity of the electric field increased or the percentage of filtered water reduced (in both nanotubes), in which the intramolecular and intermolecular forces intensified by the action of the electric field contribute to retain the heavy metal ions due to the evanescent effect. The best results for nanofiltration in carbon and boron nanotubes occur under the field 10-8 au. Since the filtration in the boron nitride nanotubes, a small difference in the percentage of filtered water for the boron nitride nanotube was the most effective (90 to 98%) in relation to the carbon nanotube (80 to 90%). The greater hydrophobicity and thermal stability of boron nanotubes are some of the factors that contributed to this result.

scholarly journals The Impact of the Electric Field on Surface Condensation of Water Vapor: Insight from Molecular Dynamics Simulation

Nanomaterials ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 64 ◽  
Author(s):  
Qin Wang ◽  
Hui Xie ◽  
Zhiming Hu ◽  
Chao Liu
Keyword(s):  
Molecular Dynamics ◽  
Water Vapor ◽  
Electric Field ◽  
Intermolecular Forces ◽  
Dynamics Simulation ◽  
Water Molecules ◽  
Attraction Force ◽  
Condensation Rate ◽  
Shape Transformation ◽  
The Impact

In this study, molecular dynamics simulations were carried out to study the coupling effect of electric field strength and surface wettability on the condensation process of water vapor. Our results show that an electric field can rotate water molecules upward and restrict condensation. Formed clusters are stretched to become columns above the threshold strength of the field, causing the condensation rate to drop quickly. The enhancement of surface attraction force boosts the rearrangement of water molecules adjacent to the surface and exaggerates the threshold value for shape transformation. In addition, the contact area between clusters and the surface increases with increasing amounts of surface attraction force, which raises the condensation efficiency. Thus, the condensation rate of water vapor on a surface under an electric field is determined by competition between intermolecular forces from the electric field and the surface.

scholarly journals Evaluation of soil contamination by heavy metals in the zone of TPP influence

2019 ◽  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Soil Contamination ◽  
Metal Ions ◽  
Electrostatic Precipitator ◽  
Chemical Elements ◽  
Thermal Power ◽  
Practical Significance ◽  
Donets Basin ◽  
The Impact

Abstract. Thermal power engineering takes one of the first places by the scale of the impact on the environment. Thermal power plant emissions are mainly deposited on the ground. Soil compounds, binding heavy metal ions (НM) for a long time, prevent their migration. The buffer capacity of the soil for metals depends on many factors: soil composition, acidity, complexity, oxidation–reduction,sorption–desorption, etc. Examination of the HM content in the soils is necessary for monitoring the environment, its protection from pollution. One of the largest pollutants in Kharkiv region is Zmiiv TPP. The goal of the work is to find out peculiarities of heavy metal contamination of the soil near the Zmiiv TTP and develop recommendations on improving the situation. In order to reach the goal, the following tasks have been solved: features of accumulation of various heavy metals in the soils have been specified, dependence between the soils pH and presence of certain chemical elements in them has been defined, dependance between the content of contamination and development of slow soluble compounds in the soil has been studied. Research methodology. The main principle of control for soil contamination is checking of concentration compliance with the established maximum permissible concentration (MPC) and approximate permissible concentration (APC). HM concentrations in the aqueous extract from the soil were determined by the atomic-emission spectral analysis, atomic absorption analysis and by the method of capillary electrophoresis. To determine the composition of the solid inorganic part of soils X-ray phase analysis was performed. Results of research. It is established that the most polluted areas are located within 10 km from TPP. The most disseminated pollutants in the area are Cu, Br, Co, V, Cr. The soils of the Siverskyi Donets Basin retain Cu, Zn and Pb ions to a large extent. Scientific novelty. Metals V, Cr are anionogenics, acid residues are formed in slightly alkaline soils and together with HM they form insoluble or slightly soluble compounds leading to their accumulation. Compounds SrCrO4, SrCr2O7, Sr(VO3)2, Zn2V2О7, Zn3(VО4)2, Zn(VО3)2 were found in the soils. Based on the determination of the coefficients of poly-elemental contamination, it is shown that maximum concentrations of HM are higher and variations of concentrations are wider except Pd, Zn and Cd in the soils with high humus, buffering and ability to form complexes with metal ions. The correlation relationships between pH, macro- and і microelements in various soils are determined. The highest correlation coefficient is between Al concentration and pH (0.6-0.9). Practical significance. Recommendations have been developed to reduce the level of soil contamination near Zmiiv TPP: reconstruction of the boiler unit, installation of an electrostatic precipitator to collect ash, using ash and slag waste in the production of Portland cement, liming soil for discrimination of HM.

scholarly journals Impact of ions of zinc and cadmium on body weight, fertility and condition of the tissues and organs of Procambarus virginalis (Decapoda, Cambaridae)

2017 ◽  
Vol 8 (4) ◽  
pp. 628-632 ◽  
Author(s):  
O. M. Marenkov ◽  
K. K. Holoborodko ◽  
U. S. Voronkova ◽  
O. S. Nesterenko
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Ions ◽  
Reproductive System ◽  
Heavy Metal Ions ◽  
Secretory Cells ◽  
Histological Structure ◽  
Cadmium Ions ◽  
Negative Effect ◽  
The Impact

Heavy metals cause functional disorders in the tissues and organs of hydrobionts, affecting their linear-weight indicators, reproductive system, digestive and eliminative organs. Using the method of histological estimation of the conditions of the tissues and organs of Procambarus virginalis Lyko, 2017 allowed us to determine the peculiarities of adaptation of crustaceans to the effect of different concentrations of heavy metal ions in the conditions of a modeling experiment. We studied the impact ions of zinc (0.1 mg/l) and cadmium (0.01 mg/l) on the organism of P. virginalis. The heavy metal ions had a negative effect on the weight indicators, survivability and reproduction of P. virginalis. During the experiments with zinc, we observed death of 18.2% of the tested сrustaceans; the highest death rate was observed in the experiment with cadmium – 27.3%. Experimentally modeled concentrations of heavy metals negatively affected the reproductive system of P. virginalis. In the experiment with cadmium ions, we observed no spawning; the highest percentage of the females with deposed eggs was observed in the control – 29.1%. The conducted studies allowed us to observe the reaction of the eliminatory system of P. virginalis to the impact of heavy metal ions. The impact of ions of zinc and cadmium decreased the area of secretory cells of the green gland by 10.4–14.8%. We observed grinding of the nuclear cell apparatus. Therefore, the nucleii of granulocytes were 23.6% smaller under the impact of zinc, and 17.5% smaller under the influence of cadmium. The sizes of cells and nucleus apparatus decreased mutually and proportionally; this was proven by stable indicators of nucleus-cytoplasm ratio, its value equaled 0.29–0.31 units. The given concentrations of heavy metals did not affect the histological condition of the adipose tissue, the sizes of adipocytes fluctuated within the range of 215–2178 μm2, the average equaled 872–994 μm2. We determined the negative effect of heavy metals on the histological structure of the hepatopancreas and the value of gland lumens. In the control, the area of previous section equaled 164.5 μm2 with 39 μm2 lumen. During the experiment with zinc ions the structures of hepatopancreas increased by 19.9%, and in the experiment with cadmium, we observed the highest increase in the structural elements of the tissues – by 50.2%. The worst histological condition of the cells of the tested tissues and organs of P. virginalis was observed among individuals impacted by the cadmium ions; this is explained by the high toxic effect of this heavy metal. 

Density Functional Theory Study of Antioxidant Adsorption onto Single- Wall Boron Nitride Nanotubes: Design of New Antioxidant Delivery Systems

2019 ◽  
Vol 22 (7) ◽  
pp. 470-482
Author(s):  
Samereh Ghazanfary ◽  
Fatemeh Oroojalian ◽  
Rezvan Yazdian-Robati ◽  
Mehdi Dadmehr ◽  
Amirhossein Sahebkar
Keyword(s):  
Density Functional Theory ◽  
Boron Nitride ◽  
Vitamin C ◽  
Electric Field ◽  
External Electric Field ◽  
Lipoic Acid ◽  
Density Functional ◽  
Cell Interaction ◽  
Boron Nitride Nanotubes ◽  
Functional Theory

Background: Boron Nitride Nanotubes (BNNTs) have recently emerged as an interesting field of study, because they could be used for the realization of developed, integrated and compact nanostructures to be formulated. BNNTs with similar surface morphology, alternating B and N atoms completely substitute for C atoms in a graphitic-like sheet with nearly no alterations in atomic spacing, with uniformity in dispersion in the solution, and readily applicable in biomedical applications with no obvious toxicity. Also demonstrating a good cell interaction and cell targeting. Aim and Objective: With a purpose of increasing the field of BNNT for drug delivery, a theoretical investigation of the interaction of Melatonin, Vitamin C, Glutathione and lipoic acid antioxidants using (9, 0) zigzag BNNTs is shown using density functional theory. Methods: The geometries corresponding to Melatonin, Vitamin C, Glutathione and lipoic acid and BNNT with different lengths were individually optimized with the DMOL3 program at the LDA/ DNP (fine) level of theory. Results: In the presence of external electric field Melatonin, Vitamin C, Glutathione and lipoic acid could be absorbed considerably on BNNT with lengths 22 and 29 Å, as the adsorption energy values in the presence of external electric field are considerably increased. Conclusion: The external electric field is an appropriate technique for adsorbing and storing antioxidants on BNNTs. Moreover, it is believed that applying the external electric field may be a proper method for controlling release rate of drugs.

scholarly journals Heavy-Metal Contents and the Impact of Roasting on Polyphenols, Caffeine, and Acrylamide in Specialty Coffee Beans

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1310
Author(s):  
Matúš Várady ◽  
Sylwester Ślusarczyk ◽  
Jana Boržíkova ◽  
Katarína Hanková ◽  
Michaela Vieriková ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Dry Matter ◽  
Green Beans ◽  
Caffeoylquinic Acids ◽  
Coffee Beans ◽  
Metal Contents ◽  
Specialty Coffee ◽  
Quantitative Analyses ◽  
The Impact

The aim of this study was to determine the effect of roasting on the contents of polyphenols (PPH), acrylamide (AA), and caffeine (CAF) and to analyze heavy metals in specialty coffee beans from Colombia (COL) and Nicaragua (NIC). Samples of NIC were naturally processed and COL was fermented anaerobically. Green beans from COL (COL-GR) and NIC (NIC-GR) were roasted at two levels, light roasting (COL-LIGHT and NIC-LIGHT) and darker roasting (COL-DARK and NIC-DARK), at final temperatures of 210 °C (10 min) and 215 °C (12 min), respectively. Quantitative analyses of PPH identified caffeoylquinic acids (CQA), feruloylquinic acids, and dicaffeoylquinic acids. Isomer 5-CQA was present at the highest levels and reached 60.8 and 57.7% in COL-GR and NIC-GR, 23.4 and 29.3% in COL-LIGHT and NIC-LIGHT, and 18 and 24.2% in COL-DARK and NIC-DARK, respectively, of the total PPH. The total PPH contents were highest in COL-GR (59.76 mg/g dry matter, DM). Roasting affected the contents of PPH, CAF, and AA (p < 0.001, p < 0.011 and p < 0.001, respectively). Nickel and cadmium contents were significantly higher in the COL-GR than in the NIC-GR beans. Darker roasting decreased AA content, but light roasting maintained similar amounts of CAF and total PPH.

Hormones Nanofiltration in Carbon Nanotubes and Boron Nitride Nanotubes Using Uniform External Electric Field Through Molecular Dynamics

2021 ◽  
Vol 21 (11) ◽  
pp. 5499-5509
Author(s):  
Rosely Maria dos Santos Cavaleiro ◽  
Tiago da Silva Arouche ◽  
Phelipe Seiichi Martins Tanoue ◽  
Tais Souza Sá Pereira ◽  
Raul Nunes de Carvalho Junior ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Boron Nitride ◽  
Electric Field ◽  
Field Potential ◽  
Boron Nitride Nanotubes ◽  
Attractive Potential ◽  
Water Molecules ◽  
Computer Simulation Study ◽  
Simulation Time

Hormones are a dangerous group of molecules that can cause harm to humans. This study based on classical molecular dynamics proposes the nanofiltration of wastewater contaminated by hormones from a computer simulation study, in which the water and the hormone were filtered in two single-walled nanotube compositions. The calculations were carried out by changing the intensities of the electric field that acted as a force exerting pressure on the filtration along the nanotube, in the simulation time of 100 ps. The hormones studied were estrone, estradiol, estriol, progesterone, ethinylestradiol, diethylbestrol, and levonorgestrel in carbon nanotubes (CNTs) and boron nitride (BNNTs). The most efficient nanofiltrations were for fields with low intensities in the order of 10-8 au and 10-7 au. The studied nanotubes can be used in membranes for nanofiltration in water treatment plants due to the evanescent field potential caused by the action of the electric field inside. Our data showed that the action of EF in conjunction with the van der Walls forces of the nanotubes is sufficient to generate the attractive potential. Evaluating the transport of water molecules in CNTs and BNNTs, under the influence of the electric field, a sequence of simulations with the same boundary conditions was carried out, seeking to know the percentage of water molecules filtered in the nanotubes.

scholarly journals Physico-chemical variability and heavy metal pollution of surface sediment in a non-channeled section of Dilúvio Stream (Southern Brazil) and the influence of channeled section in sediment pollution

2019 ◽  
Vol 14 (1) ◽  
pp. 1 ◽  
Author(s):  
Pedro Alexandre Sodrzeieski ◽  
Leonardo Capeleto de Andrade ◽  
Tales Tiecher ◽  
Flávio Anastácio de Oliveira Camargo
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Total Concentration ◽  
Mineralogical Composition ◽  
Sediment Pollution ◽  
Anthropogenic Influence ◽  
Southern Brazil ◽  
Physico Chemical ◽  
Chemical Variability ◽  
The Impact

Dilúvio Stream flows through an area with a great population density in Porto Alegre, Southern Brazil. The anthropogenic influence in the surroundings impacted negatively the quality of the sediments of Dilúvio Stream and Lake Guaíba. This study evaluated the physico-chemical variability of surface sediments in a non-channeled section of Dilúvio Stream. Additionally, we compared the concentration of several heavy metals in this section with data from previous studies in the margins of Lake Guaíba near the outflow of Dilúvio Stream in order to evaluate the impact of urbanization on sediment pollution. The pH, bulk density, particle-size distribution, electrical conductivity, organic carbon, assimilable phosphorus, total nitrogen, mineralogical composition (X-ray diffractogram) and pseudo total concentration of several metals (Fe, Al, Ca, Mg, Na, K, Mn, Ba, Zn, V, As, Pb, Cu, Cr, Co, Ni, Cd, Mo, and Se) were evaluated. The results showed that the sediments in the non-channeled section of Dilúvio Stream are predominantly sandy, with heavy metal contents below the quality reference values. Quartz and feldspar predominated in all sites. The concentration of Zn, Pb, Cu, Cr, and Ni were lower than that observed in the margins of Lake Guaíba near the outflow of Dilúvio Stream, possibly due to pollution input throughout the channeled section. The Dilúvio Stream shows indications of an anthropogenic influence in the heavy metals concentration through the channeled area.

scholarly journals A New Ex Vivo Model to Evaluate the Hair Protective Effect of a Biomimetic Exopolysaccharide against Water Pollution

Cosmetics ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 78
Author(s):  
Claire Tubia ◽  
Alfonso Fernández-Botello ◽  
Jan Dupont ◽  
Eni Gómez ◽  
Jérôme Desroches ◽  
...  
Keyword(s):  
Water Pollution ◽  
Heavy Metals ◽  
Heavy Metal ◽  
Adverse Effects ◽  
Inductively Coupled Plasma ◽  
Ex Vivo ◽  
Polluted Water ◽  
Ex Vivo Model ◽  
Fiber Damage ◽  
The Impact

As an external appendage, hair is exposed to multiple stresses of different origins such as particles and gases in air, or heavy metals and chemicals in water. So far, little research has addressed the impact of water pollution on hair. The present study describes a new ex vivo model that allowed us to document the adverse effects of water pollutants on the structure of hair proteins, as well as the protective potential of active cosmetic ingredients derived from a biomimetic exopolysaccharide (EPS). The impact of water pollution was evaluated on hair from a Caucasian donor repeatedly immersed in heavy metal-containing water. Heavy metal retention in and on hair was then quantified using Inductively Coupled Plasma Spectrometry (ICP/MS). The adverse effects of heavy metals on the internal structure of hair and its prevention by the EPS were assessed through measurement of keratin birefringence. Notably, the method allows the monitoring of the organization of keratin fibers and therefore the initial change on it in order to modulate the global damage in the hair. Results revealed an increasing amount of lead, cadmium and copper, following multiple exposures to polluted water. In parallel, the structure of keratin was also altered with exposures. However, heavy metal-induced keratin fiber damage could be prevented in the presence of the tested EPS, avoiding more drastic hair problems, such as lack of shine, or decrease in strength, due to damage accumulation.

scholarly journals Estimation of the Concentration of Some Heavy Metals in Groundwater in Rutba City

2021 ◽  
Vol 904 (1) ◽  
pp. 012009
Author(s):  
A W Abd Byty ◽  
M A Gharbi ◽  
A H Assaf
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Large Scale ◽  
Toxic Metal ◽  
Scale Production ◽  
Future Health ◽  
Distribution Maps ◽  
Guideline Values

Abstract Toxic metal pollutants in groundwater should be identified to prevent future health risks. In this paper, the presence of heavy metals in groundwater in the western region of Iraq was investigated. The heavy metals concentrations, including Ni2+, Co2+, Zn2+, Pb2+, Cr3+, Cd2+, As3+ and Hg2+ were explored in twenty selected aquifers near Rutba City and the results were presented as spatial distribution maps. Findings indicate that contamination with the investigated heavy metal ions possesses a serious threat to the study area’s groundwater quality when compared to WHO and IEPA guideline values. Thus, a new approach to remove or adsorb heavy metal ions can be developed for large-scale production and the safe use of these aquifers water. Results revealed that the highest concentrations in mg/L1 of 2.312 in w19, 1.098 in w2, 5.78 in w17, 0.292 in w9, 3.349 in w5, 0.32 in w13, 0.074 in w11 and 5.622 in w1 for Zn2+, Cr3+, As3+, Pb2+, Ni2+, Co2+, Cd2+ and Hg2+ were recorded, respectively.

scholarly journals The Influence of Heavy Metal Ions on the Viability and Metabolic Enzyme Activity of the Marbled Crayfish Procambarus virginalis (Lyko, 2017)

2018 ◽  
Vol 70 ◽  
pp. 11-23 ◽  
Author(s):  
Oleg Marenkov ◽  
Mykola V. Prychepa ◽  
Julia Kovalchuk
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Enzyme Activity ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Physiological State ◽  
Metabolic Enzyme ◽  
Nickel Ions ◽  
The Individual ◽  
Marbled Crayfish

In the experiment with marbled crayfishProcambarusvirginalis(Lyko, 2017), chronic effects of various concentrations of heavy metal ions on the physiological state and enzyme activity were investigated. The obtained results showed that among the investigated heavy metals nickel ions influenced the weight indexes and mortality of crustaceans the most negatively. According to the results of the research, significant changes were noted in the individual biochemical parameters of marbled crayfish under the influence of manganese, lead and nickel ions. The most significant changes in the activity of lactate dehydrogenase were detected in muscle tissues affected by manganese and nickel ions. A significant decrease in the activity of succinate dehydrogenase in muscle of marbled crayfish was determined after the action of heavy metal ions. Investigation of changes in the activity of alkaline phosphatase under the influence of the ions of manganese, lead and nickel has its own characteristics, which indicates certain violations in the tissues of cell membranes. Changes in the activity of enzymes were also reflected in the overall protein content. Changes in these parameters may indicate a rapid biochemical response of crustaceans to the toxic effects of heavy metals.

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