scholarly journals Pyrogenic Influence n Geochemistry Migration Ability of Heavy Metal

2018 ◽  
Keyword(s):  
Heavy Metals ◽  
Chemical Elements ◽  
Soluble Form ◽  
Soil Reaction ◽  
Migration Ability ◽  
Ph Values ◽  
Wide Range ◽  
Migration Potential ◽  
Order Of Magnitude ◽  
Migration Capacity

Purpose. Investigation of dynamics of geochemical migration ability of heavy metals as a result of the effect of man-made loading of pyrogenic origin. Methods. Analytical: atomic absorption analysis, pH-metric; the range of precipitation of hydroxides and the region of predominance of soluble hydroxocomplexes have been studied by constructing concentration-logarithmic diagrams (CRLs). Results. The results indicate the transformation of their migration properties. The diversity and versatility of behavior of chemical elements in environmental components after the fire was noted. In different ecological conditions, it is possible to observe a wide range of quantitative values of geochemical migration or accumulation of any particular chemical element. Analytical results show that the contents of migrant elements, pH values, areas of incidents, which are approximately in the same conditions, but passed by the grass or upper fire differ quite tangibly. Heavy metals that hit the environment can form difficult soluble hydroxides. In addition, in the soil solution, there is a probability of the formation of hydroxocomplexes with different amounts of hydroxide ions by metals. The range of precipitation of hydroxides and the region of predominance of soluble hydroxocomplexes have been studied by constructing concentration-logarithmic diagrams. On the basis of the calculations it can be argued that the influence of the technogenic loading of pyrogenic origin on the geochemical migration of heavy metals takes place. Compounds Fe3+ at the pH = 4.5-14, Cu2+ at pH = 7-14, Cr2+ at pH = 7-9, Zn2+ at pH= 8-11, Ni2+ at pH = 8-14 have the lowest migration potential. Compounds Pb2+ at pH = 9-12, Fe2+ - pH = 9.5-14 have the lowest migration potential also. In a more acidic _____________________________________________________ © Буц Ю. В., Крайнюк О. В., Барбашин В. В., Кобзін В. Г. , 2018 environment, soluble substances are formed, but at a pH increase of only 0,5-1, they can decrease their mobility by an order of magnitude, which contributes to their concentration in the soils after the fire. In a neutral soil reaction, most of the heavy metals (Al, Cr, Zn, Cu, Fe (II), Ni) are in a slightly soluble form (in the form of hydroxides), with their migration capacity insignificant, which leads to the accumulation of these chemical elements in the soil . In a separate group it is necessary to allocate heavy metals moving in a neutral environment (Fe (II), Cd, Co, Mg, Mn). Any increase in pH values contributes to their fixation. Conclusions. The obtained calculations can be used to predict the geochemical migration of heavy metals in soils after the man-made consequences of emergencies of pyrogenic origin.

scholarly journals Influence of technogenic loading of pyrogenic origin on the geochemical migration of heavy metals

2018 ◽  
Vol 27 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Y. Buts ◽  
V. Asotskyi ◽  
O. Kraynyuk ◽  
R. Ponomarenko
Keyword(s):  
Heavy Metals ◽  
Chemical Elements ◽  
Soluble Form ◽  
Soil Reaction ◽  
Ph Values ◽  
Wide Range ◽  
Migration Potential ◽  
Order Of Magnitude ◽  
Migration Capacity ◽  
Heavy Metals In Soils

The study of geochemical aspects of the transformation of migration properties of heavy metals under the influence of anthropogenic loading of pyrogenic origin has been given insufficient attention. We studied the concentration of heavy metals in soils by atomic absorption analysis. The results indicate the transformation of their migration properties. The diversity and versatility of behaviour of chemical elements in environmental components after fire was noted. In different ecological conditions, it is possible to observe a wide range of quantitative values of geochemical migration or accumulation of any particular chemical element. The analytical results show that the contents of migrant elements, pH values, areas of disasters which are approximately in the same conditions, but passed by the grass or upper fire differ quite tangibly. Heavy metals that hit the environment can form difficult soluble hydroxides. In addition, in the soil solution, there is a probability of the formation of hydroxocomplexes with different amounts of hydroxide ions by metals. The range of precipitation of hydroxides and the region of predominance of soluble hydroxocomplexes have been studied by constructing concentration-logarithmicdiagrams. On the basis of the calculations it can be argued that the influence of technogenic loading of pyrogenic origin influences the geochemical migration of heavy metals . Compounds Fe3+ at the pH = 4.5-14, Cu2+ at pH = 7-14, Cr2+ at pH = 7-9, Zn2+ at pH= 8-11, Ni2+ at pH = 8-14 have the lowest migration potential. Compounds Pb2+ at pH = 9-12, Fe2+ - pH = 9.5-14 have the lowest migration potential also. In a more acidic environment, soluble substances are formed, but at a pH increase of only 0.5-1, they can decrease their mobility by an order of magnitude which contributes to their concentration in the soils after the fire. In a neutral soil reaction, most of the heavy metals (Al, Cr, Zn, Cu, Fe (II), Ni) are in a slightly soluble form (in the form of hydroxides), with insignificant, migration capacity which leads to the accumulation of these chemical elements in the soil. It is necessary to allocate heavy metals moving in a neutral environment (Fe (II), Cd, Co, Mg, Mn) into a separate group. Any increase in pH values contributes to their fixation. The obtained calculations can be used to predict the geochemical migration of heavy metals in soils which result from anthropogenic disasters of a pyrogenic origin.

A Comprehensive Review of Minerals, Trace Elements, and Heavy Metals in Saffron

2022 ◽  
Vol 23 ◽  
Author(s):  
Sayyed Mohammad Ali Noori ◽  
Mohammad Hashemi ◽  
Sajjad Ghasemi
Keyword(s):  
Heavy Metals ◽  
Trace Elements ◽  
Inductively Coupled Plasma ◽  
Chemical Elements ◽  
Absorption Spectrometry ◽  
Atomic Emission ◽  
Emission Spectrometry ◽  
Inductively Coupled ◽  
Wide Range ◽  
The World

Abstract: Saffron is one of the most expensive spices in the world, and its popularity as a tasty food additive is spreading rapidly through many cultures and cuisines. Minerals and heavy metals are minor components found in saffron, which play a key role in the identification of the geographical origin, quality control, and food traceability, while they also affect human health. The chemical elements in saffron are measured using various analytical methods, such as techniques based on spectrometry or spectroscopy, including atomic emission spectrometry, atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. The present study aimed to review the published articles about heavy metals and minerals in saffron across the world. To date, 64 chemical elements have been found in different types of saffron, which could be divided into three groups of macro-elements, trace elements, and heavy metals (trace elements with a lower gravity/greater than five times that of water and other inorganic sources). Furthermore, the chemical elements in the saffron samples of different countries have a wide range of concentrations. These differences may be affected by geographical condition such as physicochemical properties of the soil, weather and other environmental conditions like saffron cultivation and its genotype.

scholarly journals HEAVY METALS DISTRIBUTION TRENDS ON "OLESHKIVSKI PISKY" MILITARY TRAINING SITE

2020 ◽  
pp. 42-48
Author(s):  
А. Splodytel
Keyword(s):  
Heavy Metals ◽  
Inductively Coupled Plasma ◽  
Gamma Ray ◽  
Soil Cover ◽  
Chemical Elements ◽  
Military Training ◽  
Fluorescence Analysis ◽  
Water Soluble ◽  
Soluble Form ◽  
Training Site

The results of ecological-geochemical researches of soil cover of "Oleshkivski pisky" military training site, using maximum allowable concentration and classification of chemical elements with respect to hazard classes are presented. Analytical works to identify gross content and heavy metals movable forms in soils were defined by methods of atomic absorption and mass-spectometry with inductively coupled plasma (ICPMS) as well as by using gamma-ray activation analysis and X-ray fluorescence analysis. Analysis and interpretation of the coefficients of heavy metal components concentration were conducted based on landscape and geochemical fundamentals. The regular network of the protoselection points was developed. This network is built taking into account landscape structure of the territory, and provides control over landscape and geochemical currents and barriers. The average index of soil cover pollution of the polygon was calculated taking into account different toxicity of the elements. This index reaches its maximum in the region of firing positions and military polygon. The average Zc index of the upper soil level is 32, which corresponds to the dangerous level of soil pollution. The research revealed the content of moveable forms of heavy metals in soil cover of the polygon in order to identify toxic and tolerant levels of heavy metals concentration and reserve sources of elements in soils, which can maintain optimal concentration level in soil solution. It was defined that content of heavy metals in three movable forms are represented in the following geochemical units, mg/kg: in acid soluble form – Mn > Zn > Pb > Cu > V > Ni > Co > Cd; in exchangeable form – Mn > Zn > Pb > V > Co = Ni > Cu > Cd; in water soluble form – Mn > Zn > Pb = V > Co > Ni > Cd > Cu. The article presents research results on accumulation intensity and the nature of distribution of gross and mobile heavy metals forms in soil and on their migration in the soil profile. The dominant technogenic geochemical unit was extracted: Cd > Hg > Pb > Cu > Zn > Ni > V > Co > Mn. Landscapes with maximum polyelement contamination have been identified.

scholarly journals Dynamics of migration property of some heavy metals in soils in Kharkiv region under the influence of the pyrogenic factor

2019 ◽  
Vol 28 (3) ◽  
pp. 409-416 ◽  
Author(s):  
Y. Buts ◽  
V. Asotskyi ◽  
O. Kraynyuk ◽  
R. Ponomarenko ◽  
P. Kovalev
Keyword(s):  
Heavy Metals ◽  
Trace Metals ◽  
Environmental Safety ◽  
Ecological Systems ◽  
Migration Ability ◽  
Metal Compounds ◽  
Hazardous Chemical ◽  
Mobile Forms ◽  
And Migration ◽  
Migration Capacity

In soils after fires trace metals sharply change their migration ability and can form poorly-soluble hydroxides which are hazardous chemical formations, the nature of which has not been fully explored until now. In addition, in interstitial water, there is a probability of the formation by metals of hydroxocomplexes with different amounts of hydroxide ions. We studied the range of dynamics of migration capacity of sedimentation of hydroxides and the region of predominance of soluble hydroxocomplexes by developing logarithmic concentration diagrams (LCD). We developed logarithmic concentration diagrams, the equation of formation of prevailing forms, using which it is possible to clearly determine the regions of maximum sedimentation (accumulation) of hydroxides and hydroxocomplexes of heavy metals after the influence of the pyrogenic factor. The obtained calculations of the results of the predictive modeling of the dynamics of migration capacity and postpyrogenic migration geochemical processes in ecogeosystems have been organized and systematized. The determined patterns can be useful for the analysis of possible geochemical migration (accumulation) of heavy metals in ecological systems in the study of technogenic and ecological situation after fires. Based on the calculations made, mathematical models of heavy metals` behaviour are developed, which are useful for drawing up a forecast estimation of the dynamics of their geochemical migration and accumulation in ecological systems as a result of the influence of the technogenic loading of the pyrogenic factor. The conditions of concentration and migration of compounds of heavy metals were determined, and the equation for calculating the concentration of mobile forms of trace metal compounds has been developed. The developed map of the activity of geochemical migration of heavy metals under the influence of the technogenic loading of pyrogenic factor will make it possible to elaborate the migratory capacity of trace metals and provide a forecast of their behaviour in ecological systems after fires. This will allow preventive measures to be taken to ensure environmental safety and prevent adverse effects on human health and the condition of the components of the environment. The creation of similar cartographic material may be extrapolated to other regions of Ukraine, affected by technogenic loading of pyrogenic factor. The development of logarithmic concentration diagrams allows us to predict the capacity of compounds of lead, nickel, chromium,and copper for migration or accumulation of heavy metals due to changes in the acidity of soils under the influence of the pyrogenic factor. Having used the map of the soils of the Kharkiv region, we analyzed and provided a forecast of the migration ability of lead compounds in cases of fire in different types and subtypes of different environmental conditions.

scholarly journals Possibilities of Determination of Risk Elements in Alluvial Agriculture Soils in the Mže and Otava River Basins by X-Ray Fluorescence Spectrometry

2020 ◽  
Vol 66 (1) ◽  
pp. 15-23
Author(s):  
Ladislav Menšík ◽  
Lukáš Hlisnikovský ◽  
Ladislav Holík ◽  
Pavel Nerušil ◽  
Eva Kunzová
Keyword(s):  
Heavy Metals ◽  
Chemical Elements ◽  
Correlation Coefficients ◽  
River Basins ◽  
Risk Elements ◽  
Wide Range ◽  
Organic Fertilisers ◽  
Multiple Correlation Coefficients ◽  
The Relationship

AbstractThe undesirable, hazardous, and risk elements are introduced into all environmental parts through human activities. They enter the soil and aquatic environment by atmospheric deposition, or by application of sewage sludge, pesticides, mineral and organic fertilisers, and by organic manures. Heavy metals (HMs) and risk elements can be determined in the soil by a wide range of analytical methods that differ in terms of time and financial costs, and the demands on service. One of the methods is the use of a portable XRF spectrometer under lab conditions, offering relatively fast determination of the concentration of chemical elements in the soil. In the presented study we evaluated the accuracy and the precision of the XRF device for analysis of the concentration of heavy metals (Pb, Zn, As, Mn, Cu, and Ni) in alluvial soils from the Mže and Otava river basins (Czech Republic), and validated and compared obtained results with the conventional lab method (ICP-OES). The soil samples (n = 502) were taken at 43 sampling sites at depths of 0 – 30, 30 – 60, and 60 – 90 cm, mainly in floodplains with Fluvisol soil type (N-year flow rates = Q100 m3/s). The multiple correlation coefficients R values ranged from 0.81 to 0.99. The R2 determination coefficients for individual HMs, measured by XRF, were determined as follows: Pb – 0.98, Zn – 0.97, Cu – 0.80, Mn – 0.79, As – 0.78, Ni – 0.66. According to our results, 66 – 98% points fit the designed models. The Pb and Zn have the best dependency (relationship tightness), and regression models are excellent. Cu, Mn, and As have a slightly worse dependency (tightness of the relationship), but the regression model is still very well suitable for agriculture practice, or for the purposes of environmental monitoring.

Extending the Applicability of the ANI Deep Learning Molecular Potential to Sulfur and Halogens

2020 ◽  
Author(s):  
Christian Devereux ◽  
Justin Smith ◽  
Kate Davis ◽  
Kipton Barros ◽  
Roman Zubatyuk ◽  
...  
Keyword(s):  
Drug Development ◽  
Autonomous Vehicles ◽  
Potential Energy Surfaces ◽  
Organic Molecules ◽  
Chemical Elements ◽  
Molecular Potential ◽  
Wide Range ◽  
Energy Surfaces ◽  
New Applications ◽  
Physical Phenomena

<p>Machine learning (ML) methods have become powerful, predictive tools in a wide range of applications, such as facial recognition and autonomous vehicles. In the sciences, computational chemists and physicists have been using ML for the prediction of physical phenomena, such as atomistic potential energy surfaces and reaction pathways. Transferable ML potentials, such as ANI-1x, have been developed with the goal of accurately simulating organic molecules containing the chemical elements H, C, N, and O. Here we provide an extension of the ANI-1x model. The new model, dubbed ANI-2x, is trained to three additional chemical elements: S, F, and Cl. Additionally, ANI-2x underwent torsional refinement training to better predict molecular torsion profiles. These new features open a wide range of new applications within organic chemistry and drug development. These seven elements (H, C, N, O, F, Cl, S) make up ~90% of drug like molecules. To show that these additions do not sacrifice accuracy, we have tested this model across a range of organic molecules and applications, including the COMP6 benchmark, dihedral rotations, conformer scoring, and non-bonded interactions. ANI-2x is shown to accurately predict molecular energies compared to DFT with a ~10<sup>6</sup> factor speedup and a negligible slowdown compared to ANI-1x. The resulting model is a valuable tool for drug development that can potentially replace both quantum calculations and classical force fields for myriad applications.</p>

Nitrogen Removal from Anaerobically-Treated Leachate

1984 ◽  
Vol 19 (1) ◽  
pp. 87-100
Author(s):  
D. Prasad ◽  
J.G. Henry ◽  
P. Elefsiniotis
Keyword(s):  
Nitrogen Removal ◽  
Air Flow ◽  
Operating Conditions ◽  
Air Flow Rate ◽  
Flow Rates ◽  
Anaerobic Filter ◽  
Ph Values ◽  
Wide Range ◽  
Ammonia Desorption ◽  
Effects Of Ph

Abstract Laboratory studies were conducted to demonstrate the effectiveness of diffused aeration for the removal of ammonia from the effluent of an anaerobic filter treating leachate. The effects of pH, temperature and air flow on the process were studied. The coefficient of desorption of ammonia, KD for the anaerobic filter effluent (TKN 75 mg/L with NH3-N 88%) was determined at pH values of 9, 10 and 11, temperatures of 10, 15, 20, 30 and 35°C, and air flow rates of 50, 120, and 190 cm3/sec/L. Results indicated that nitrogen removal from the effluent of anaerobic filters by ammonia desorption was feasible. Removals exceeding 90% were obtained with 8 hours aeration at pH of 10, a temperature of 20°C, and an air flow rate of 190 cm3/sec/L. Ammonia desorption coefficients, KD, determined at other temperatures and air flow rates can be used to predict ammonia removals under a wide range of operating conditions.

Mercury Removal from Wastewater by Steamed Hoof Powder

1999 ◽  
Vol 40 (7) ◽  
pp. 109-116 ◽  
Author(s):  
M. H. Ansari ◽  
A. M. Deshkar ◽  
P. S. Kelkar ◽  
D. M. Dharmadhikari ◽  
M. Z. Hasan ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Adsorption Capacity ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Light Metal ◽  
Mercury Removal ◽  
High Adsorption ◽  
Surface Sites ◽  
Ph Values ◽  
High Adsorption Capacity

Steamed Hoof Powder (SHP), size &lt; 53μ, was observed to have high adsorption capacity for Hg(II) with &gt;95% removal from a solution containing 100 mg/L of Hg(II) with only 0.1% (W/V) concentration of SHP. The SHP has good settling properties and gives clear and odour free effluent. Studies indicate that pH values between 2 and 10 have no effect on the adsorption of Hg(II) on SHP. Light metal ions like Na+, K+, Ca2+ and Mg2+ up to concentrations of 500 mg/L and heavy metals like Cu2+, Zn2+, Cd2+, Co2+, Pb2+, Ni2+, Mn2+, Cr3+, Cr6+, Fe2+ and Fe3+ up to concentrations of 100 mg/L do not interfere with the adsorption process. Anions like sulphate, acetate and phosphate up to concentrations of 200 mg/L do not interfere. Chloride interferes in the adsorption process when Hg(II) concentration is above 9.7 mg/L. The adsorption equilibrium was established within two hours. Studies indicate that adsorption occurs on the surface sites of the adsorbent.

scholarly journals Stormwater Runoff Treatment Using Pervious Concrete Modified with Various Nanomaterials: A Comprehensive Review

2021 ◽  
Vol 13 (15) ◽  
pp. 8552
Author(s):  
Vahid Alimohammadi ◽  
Mehdi Maghfouri ◽  
Delaram Nourmohammadi ◽  
Pejman Azarsa ◽  
Rishi Gupta ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Compressive Strength ◽  
Adsorption Capacity ◽  
Removal Rate ◽  
Stormwater Runoff ◽  
Infiltration Rate ◽  
Stormwater Treatment ◽  
Adsorption Mechanisms ◽  
Wide Range ◽  
Adsorption Processes

Clean water is a vital need for all living creatures during their lifespan. However, contaminated stormwater is a major issue around the globe. A wide range of contaminants, including heavy metals, organic and inorganic impurities, has been discovered in stormwater. Some commonly utilized methods, such as biological, physical and chemical procedures, have been considered to overcome these issues. However, these current approaches result in moderate to low contaminant removal efficiencies for certain classes of contaminants. Of late, filtration and adsorption processes have become more featured in permeable concretes (PCs) for the treatment of stormwater. As nanoparticles have vast potential and unique characterizations, such as a higher surface area to cure polluted stormwater, employing them to improve permeable concretes’ capabilities in stormwater treatment systems is an effective way to increase filtration and adsorption mechanisms. The present study reviews the removal rate of different stormwater contaminants such as heavy metals, organic and other pollutants using nanoparticle-improved PC. The application of different kinds of nanomaterials in PC as porous media to investigate their influences on the properties of PC, including the permeability rate, compressive strength, adsorption capacity and mix design of such concrete, was also studied. The findings of this review show that different types of nanomaterials improve the removal efficiency, compressive strength and adsorption capacity and decrease the infiltration rate of PC during the stormwater treatment process. With regard to the lack of comprehensive investigation concerning the use of nanomaterials in PC to treat polluted stormwater runoff, this study reviews 242 published articles on the removal rate of different stormwater contaminants by using PC improved with nanoparticles.

scholarly journals Hybrid Acrylated Chitosan and Thiolated Pectin Cross-Linked Hydrogels with Tunable Properties

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 266
Author(s):  
Shaked Eliyahu ◽  
Alexandra Galitsky ◽  
Esther Ritov ◽  
Havazelet Bianco-Peled
Keyword(s):  
Electrostatic Interactions ◽  
Profile Analysis ◽  
Hybrid Hydrogel ◽  
Texture Profile ◽  
Ph Values ◽  
X Ray Scattering ◽  
Wide Range ◽  
Michael Type Addition ◽  
Physical And Chemical ◽  
Hydrogel System

We developed and characterized a new hydrogel system based on the physical and chemical interactions of pectin partially modified with thiol groups and chitosan modified with acrylate end groups. Gelation occurred at high pectin thiol ratios, indicating that a low acrylated chitosan concentration in the hydrogel had a profound effect on the cross-linking. Turbidity, Fourier transform infrared spectroscopy, and free thiol determination analyses were performed to determine the relationships of the different bonds inside the gel. At low pH values below the pKa of chitosan, more electrostatic interactions were formed between opposite charges, but at high pH values, the Michael-type addition reaction between acrylate and thiol took place, creating harder hydrogels. Swelling experiments and Young’s modulus measurements were performed to study the structure and properties of the resultant hydrogels. The nanostructure was examined using small-angle X-ray scattering. The texture profile analysis showed a unique property of hydrogel adhesiveness. By implementing changes in the preparation procedure, we controlled the hydrogel properties. This hybrid hydrogel system can be a good candidate for a wide range of biomedical applications, such as a mucosal biomimetic surface for mucoadhesive testing.

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