scholarly journals Migration behavior of benzobicyclon hydrolysate and associated influencing factors in different agricultural soils

2021 ◽  
Author(s):  
Lang Liu ◽  
Lei Rao ◽  
Wenwen Zhou ◽  
Limei Tang ◽  
Baotong Li
Keyword(s):  
Influencing Factors ◽  
Agricultural Soils ◽  
Chemical Properties ◽  
Retention Factor ◽  
Tween 80 ◽  
Ammonium Bromide ◽  
Migration Behavior ◽  
Solution Ph ◽  
Potential Threat ◽  
Benzene Sulfonic Acid

Abstract. Benzobicyclon is a triketone pro-herbicide that needs to be hydrolyzed to form an active compound benzobicyclon hydrolysate (BH). This study aimed to investigate the migration behavior of BH in different types of agricultural soil and the associated influencing factors. Soil thin-layer chromatography and column leaching tests were used to study the migration behavior of BH in these soils. Based on the mobility retention factor (Rf = 0.34–0.90), the mobility of BH in thin soil layers was ranked in the order Lixisols > Anthrosols > Ferralsols > Phaeozems. The Rf value of BH was linearly positively correlated with soil sand content and pH, and negatively correlated with other physical and chemical properties of soil. BH was difficult to leach in Phaeozems, less difficult to leach in Ferralsols, and easy to leach in Anthrosols and Lixisols. Increasing the BH dosage and rainfall amount or adding humic acid and anionic (dodecyl benzene sulfonic acid) or nonionic (Tween-80) surfactant blocked BH migration in soil columns. In contrast, increasing the leaching solution pH and adding cationic surfactant (cetyl trimethyl ammonium bromide) promoted BH migration in soil columns.BH application has a low risk of groundwater pollution in Phaeozems and Ferralsols, but poses a potential threat to groundwater in Anthrosols and Lixisols.

scholarly journals Abandoned agricultural soils from the central part of the Yamal region of Russia: morphology, diversity, and chemical properties

2020 ◽  
Vol 5 (1) ◽  
pp. 94-106
Author(s):  
Evgeny Abakumov ◽  
Evgeniya Morgun ◽  
Alexandr Pechkin ◽  
Vyacheslav Polyakov
Keyword(s):  
Land Use ◽  
Agricultural Soils ◽  
Anthropogenic Impacts ◽  
Chemical Properties ◽  
Organic Carbon Content ◽  
Active Growth ◽  
Natural Processes ◽  
Agrochemical Properties ◽  
Fallow Lands ◽  
Abandoned Lands

AbstractThe post-anthropogenic and soil cover transformations of former agricultural soils on the abandoned lands in the Russian Arctic territory are poorly investigated due to the active growth of the city complexes and increasing area occupied by agricultural lands. That is lead to an increase in the area of the arable lands surrounding the polar urbanized territories. Today, most of that land allocated for agricultural needs has been abandoned or affected by other types of land use. This study aimed to investigate the abandoned lands surrounding some of the settlements in the central part of the Yamal region. The soil diversity, morphology, and chemical and agrochemical properties were investigated with special reference to the specific transformations that occur to fallow lands under permafrost-affected cryogenic-ecosystem conditions. Analysis of data show that these soils are characterized by features relating to both, previous (and existing), anthropogenic impacts and natural processes such as cryogenic mass transfer. The degradation of the arable humus-enriched horizon was not as pronounced as it has been in more humid boreal environments over recent decades. The organic carbon content in topsoil depends on the land use and varied considerably among the soil types. The former arable topsoil horizon has been stable over time in terms of its morphological features and agrochemical state. Despite the high soil acidity levels, thenutrient content in the anthropogenically impacted soils was still high, even though being abandoned for 20 years.

Effect of Grinding Aids on the Fracture Energy of Mica

2011 ◽  
Vol 402 ◽  
pp. 503-509
Author(s):  
Ze Hong Wang ◽  
Fu Jia Yu ◽  
Shan Cai ◽  
Shan Zhi Deng ◽  
Roger Horn
Keyword(s):  
Sodium Chloride ◽  
Fracture Energy ◽  
Sodium Citrate ◽  
Ph Value ◽  
Sodium Tripolyphosphate ◽  
Experimental System ◽  
Ammonium Bromide ◽  
Solution Ph ◽  
Grinding Aids ◽  
Slurry Rheology

An extension of the classical Obriemoff experiments has been set up to measure the fracture energy of mica. This experimental system will be entirely independent of slurry rheology. CTAB (Cetyl Trimethyl Ammonium Bromide), sodium tripolyphosphate, sodium hexametaphosphate, and tri-sodium citrate are used as grinding aids in this study and the fracture energy has been measured for mica in air, water, and water with the addition of various concentrations of these grinding aids. The results show that the fracture energy of mica in water is about half of what it is in air. Grinding aids are shown to reduce the fracture energy of mica, but not dramatically. Addition of grinding aids reduces the fracture energy by a further 10-20%, with tri-sodium citrate appearing to be the most effective. For each grinding aid there appears to be an optimal concentration, typically around 10 mmol. An experiment is also done with sodium chloride at a range of concentrations to investigate the mechanism of these grinding aids, but no reduction in fracture energy (compared to water) was observed, hence the molecular-level mechanism of action of these grinding aids remains unclear. The effect of solution pH values on the fracture energy are also investigated using tri-sodium citrate and sodium chloride. The results show that the solution pH value may effect on the fracture energy of mica. So, in practice, both concentration and pH value of solution are important for getting better grinding results.

Sethoxydim Response to Spray Carrier Chemical Properties and Environment

1994 ◽  
Vol 8 (3) ◽  
pp. 591-597 ◽  
Author(s):  
John D. Nalewaja ◽  
Robert Matysiak ◽  
Edward Szelezniak
Keyword(s):  
Low Temperature ◽  
Sodium Bicarbonate ◽  
Leaf Surface ◽  
Uv Light ◽  
Chemical Properties ◽  
Ammonium Hydroxide ◽  
Ammonium Salts ◽  
Uv Degradation ◽  
Solution Ph ◽  
Spray Solution

Experiments were conducted to determine the influence of spray carrier salts, UV light, and temperature on sethoxydim phytotoxicity to oat or yellow foxtail. Spray solution pH and ions present were both important to sethoxydim phytotoxicity to oat. Sodium and calcium salts were antagonistic to sethoxydim phytotoxicity only when the spray carrier pH exceeded 7. Ammonium salts and ammonium hydroxide were synergistic with sethoxydim, and the synergism was independent of spray solution pH. Ammonium sulfate, but not ammonium hydroxide, overcame sodium bicarbonate antagonism of sethoxydim. The antagonism of sethoxydim phytotoxicity by sodium bicarbonate was greatest in the presence of UV light and most pronounced when treated plants were exposed to mid-day sunlight. Sodium bicarbonate or low temperature may reduce the speed of sethoxydim absorption allowing for greater UV degradation of unabsorbed sethoxydim on the leaf surface.

scholarly journals Distinct Dispersion of As, Cd, Pb, and Zn in Farmland Soils near Abandoned Mine Tailings: Field Observation Results in South Korea

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Sung-Wook Yun ◽  
Dong-Hyeon Kang ◽  
Won-Hyun Ji ◽  
Mun-Ho Jung ◽  
Chan Yu
Keyword(s):  
Agricultural Soils ◽  
Mine Tailing ◽  
Migration Behavior ◽  
Dispersion Characteristics ◽  
Gis Technology ◽  
Metal Mine ◽  
Tailing Dumps ◽  
Groundwater Environment ◽  
Abandoned Mine Tailings ◽  
Observation Results

We investigated the characteristics of metal(loid) transport and dispersion in agricultural soils near an abandoned metal mine. Topsoil samples were collected from 162 sampling sites in the study area, including 1 in the mine tailing dumps, to analyze the total concentrations of As, Pb, Cd, and Zn. Subsequently, the metal(loid) transport and dispersion characteristics were investigated using geographic information system (GIS) technology. The results of this study clearly demonstrated the variation in the dispersal of As, Cd, Pb, and Zn from the mine tailing dumps to nearby agricultural soils and the element-specific spatial variability in their respective transport and dispersion characteristics. These findings suggested that compared with the migration behavior of Cd, Pb, and Zn, that of As has a farther-reaching impact on agricultural soils owing to its geochemical cycling in the soil and groundwater environment. This impact differed significantly in magnitude from that of the other investigated metals. Therefore, special consideration must be given to the migration behavior of As.

scholarly journals Adsorption Characteristics and Mechanism of Bisphenol A by Magnetic Biochar

2020 ◽  
Vol 17 (3) ◽  
pp. 1075 ◽  
Author(s):  
Jinpeng Wang ◽  
Ming Zhang
Keyword(s):  
Bisphenol A ◽  
Exothermic Reaction ◽  
Chemical Properties ◽  
Solution Ph ◽  
Acceptor Interaction ◽  
Endocrine Disrupting Chemical ◽  
Magnetic Biochar ◽  
Grapefruit Peel ◽  
Initial Adsorption ◽  
Physical And Chemical

In this paper, biochar (BC) was prepared from discarded grapefruit peel and modified to prepare magnetic biochar (MBC). Physical and chemical properties of BC and MBC were characterized, and the results showed that the type of iron oxide loaded by MBC was γ-Fe2O3. Compared with BC, MBC has a larger specific surface area and pore volume, with more oxygen-containing functional groups on the surface. BC and MBC were used to adsorb and remove endocrine-disrupting chemical (EDC) bisphenol A (BPA) from simulated wastewater. The results showed that the adsorption kinetics and adsorption isotherm of BPA adsorption by BC and MBC were mainly in accordance with the pseudo-second-order kinetics model and the Langmuir model. This indicates that the adsorption of BPA on BC and MBC is mainly a chemically controlled monolayer adsorption. Adsorption thermodynamics show that BC and MBC adsorption of BPA is a spontaneous exothermic reaction, and lowering the temperature is conducive to the adsorption reaction. The effect of solution pH on the adsorption of BPA by both was significant. The optimum pH for BC and MBC to absorb BPA was 6 and 3, respectively. The concentration of Na+ in the range of 0–0.10 mol·L−1 can promote the adsorption of BPA to MBC. MBC loaded with γ-Fe2O3 not only has excellent magnetic separation ability, but can also reach about 80% of the initial adsorption capacity after four cycles of adsorption. By analyzing the adsorption mechanism, it was found that the H-bond and the π–π electron donor–acceptor interaction (EDA) were the main forces for BC and MBC to adsorb BPA.

scholarly journals Molecular Interactions in Binary Surfactant Solutions: Effect of pH

2019 ◽  
Vol 64 (4) ◽  
pp. 437-445
Author(s):  
Olga Kochkodan ◽  
Victor Maksin ◽  
Nadiya Antraptseva ◽  
Tetyana Semenenko
Keyword(s):  
Molecular Interactions ◽  
Mixed Micelles ◽  
Ph Value ◽  
Chemical Properties ◽  
Micelle Formation ◽  
Bulk Solution ◽  
Surfactant Mixtures ◽  
Solution Ph ◽  
Solution Interface ◽  
Adsorption Layers

By using surface tension and conductivity measurements, the colloid-chemical properties of the mixtures of cationic hexadecylpyridinium bromide with nonionic Triton X-100 surfactants were investigated both in the bulk solution and at air/solution interface at different pH values. The composition of mixed micelles and adsorption layers, parameters of molecular interactions in mixed micelles βm and adsorption layers βσ, as well as standard free energies of micelle formation ΔG0mic and adsorption ΔG0ads were calculated. It was found that molecules of the nonionic surfactant presumably dominate in the mixed micelles and adsorption layers. It was shown that βm and βσ have negative values, which indicate the strengthening of intermolecular interactions in the mixed micelles and adsorption layers. Based on the data obtained, it was suggested that ion-dipole interactions are involved in the formation of intermolecular structures between nonionic and cationic surfactants in aqueous solution and at the air-solution interface. It was shown that βm, βσ as well as ΔG0mic and ΔG0ads parameter depends on the solution pH value. The complex interplay of ion-dipole, protonation and chelation processes, which occur in the surfactant mixtures at different pH and affect the strength of intermolecular interaction, should be taken into account for data analysis.

Analog Computation of Forms of Americium Presence in Aqueous Solution

2012 ◽  
Vol 549 ◽  
pp. 500-503
Author(s):  
Jie Hong Lei
Keyword(s):  
Aqueous Solution ◽  
Chemical Composition ◽  
Influencing Factors ◽  
Ph Value ◽  
Safety Evaluation ◽  
Chemical Components ◽  
Migration Behavior ◽  
Analog Computation ◽  
Geological Disposal ◽  
Geochemical Model

In geological disposal of radioactive wastes, the study of Americium migration is very important for the safety evaluation of the repository. The forms of chemical components of Americium presence in aqueous solution that directly affect its migration behavior provide a basis for analog computation of the element. This paper uses PHREEQC, the geochemical model, for analog computation of forms of Americium presence in two types of groundwater, and analyzes the morphologies of the main elements and the influencing factors. The results show that the morphology of Americium is mainly controlled by the characteristics of the chemical composition of groundwater, while the PH value also has a great impact on the forms of Americium presence.

scholarly journals Effect of Water Chemistry on Antimony Removal by Chemical Coagulation: Implications of ζ-Potential and Size of Precipitates

2019 ◽  
Vol 20 (12) ◽  
pp. 2945 ◽  
Author(s):  
Muhammad Ali Inam ◽  
Rizwan Khan ◽  
Muhammad Akram ◽  
Sarfaraz Khan ◽  
Ick Tae Yeom
Keyword(s):  
Water Chemistry ◽  
Divalent Cations ◽  
Chemical Properties ◽  
Point Of Zero Charge ◽  
Hydrodynamic Diameter ◽  
Alkaline Ph ◽  
Solution Ph ◽  
Ζ Potential ◽  
Wide Group ◽  
Co Precipitation

The process of coagulation and precipitation affect the fate and mobility of antimony (Sb) species in drinking water. Moreover, the solubility and physico-chemical properties of the precipitates may be affected by the media chemistry. Accordingly, the present study aimed to investigate the removal of Sb(III, V) species by ferric chloride coagulation under various water chemistry influences with a particular focus on the role of the properties of the precipitates. The results indicated that the amount of Sb(III) removed increased with increasing solution pH, showing the insignificant effects of the hydrodynamic diameter (HDD) and ζ-potential of the precipitates. However, no Sb(V) removal occurred at alkaline pH values, while a highly negative ζ-potential and the complete dissolution of precipitates were observed in the aqueous solution. The solution pH was also useful in determining the dominant coagulation mechanisms, such as co-precipitation and adsorption. The Fe solubility substantially affects the Sb removal at a certain pH range, while the HDD of the precipitates plays an insignificant role in Sb removal. The presence of divalent cations brings the ζ-potential of the precipitates close to point of zero charge (pzc), thus enhancing the Sb(V) removal at alkaline pH conditions. Pronounced adverse effects of humic acid were observed on Sb removal, ζ-potential and HDD of the precipitates. In general, this study may provide critical information to a wide group of researchers dealing with environmental protection from heavy metal pollution.

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