scholarly journals Water magnetization and phosphorus transport parameters in the soil

2017 ◽  
Vol 21 (1) ◽  
pp. 9-13
Author(s):  
Tarcila N. Generoso ◽  
Mauro A. Martinez ◽  
Genelício C. Rocha ◽  
Paulo J. Hamakawa
Keyword(s):  
The Other ◽  
Retardation Factor ◽  
Phosphorus Transport ◽  
Transport Parameters ◽  
Phosphate Ion ◽  
Sources Of Pollution ◽  
Magnetized Water ◽  
Crop Development ◽  
Red Latosol ◽  
Leaching Columns

ABSTRACT There are scientific studies describing changes in properties of the water when subjected to the action of a magnetic field, which may favor the availability of some nutrients in the soil solution. Some nutrients, although they are essential to the process of crop development, can be sources of pollution for watercourses and soil. The aim of this study was to evaluate the effect of water magnetization on transport parameters of the phosphate ion in a Red Latosol (RL) and in a Quartzarenic Neosol (QN). Saturated leaching columns were connected to bottles containing KH2PO4 solutions. In RL, there were significant differences in phosphorus (P) transport parameters, related to the retardation factor (R) and distribution coefficient (Kd). For the others, Peclet number (Pe), dispersive-diffusion coefficient (D) and dispersivity (λ), there were no significant differences in the comparison between the treatments with magnetized and non-magnetized water. In QN, there were statistical differences in R and Kd. For the other parameters, Pe, D and λ, there were no statistical differences between treatments.

scholarly journals Temperature effect in potassium and nitrate ions in soil transport

2008 ◽  
Vol 28 (3) ◽  
pp. 438-447 ◽  
Author(s):  
Adriano D. M. A. Gonçalves ◽  
Jarbas H. Miranda ◽  
Paulo Rossi ◽  
José F. G. Sabadin ◽  
Marcos Y. Kamogawa
Keyword(s):  
Porous Medium ◽  
Dispersion Coefficient ◽  
Potassium Nitrate ◽  
Positive Influence ◽  
Retardation Factor ◽  
Nitrate Transport ◽  
Transport Parameters ◽  
Medium Temperature ◽  
Soil Transport ◽  
Solute Dynamics

When doing researches on solute dynamics in porous medium, the knowledge of medium characteristics and percolating liquids, as well as of external factors is very important. An important external factor is temperature and, in this sense, our purpose was determining potassium and nitrate transport parameters for different values of temperature, in miscible displacement experiments. Evaluated parameters were retardation factor (R), diffusion/dispersion coefficient (D) and dispersivity, at ambient temperature (25 up to 28 ºC), 40 ºC and 50 ºC. Salts used were potassium nitrate and potassium chlorate, prepared in a solution made up of 5 ppm nitrate and 2.000 ppm potassium, with Red-Yellow Latosol porous medium. Temperature exhibited a positive influence upon porous medium solution and upon dispersion coefficient.

scholarly journals DETERMINATION OF TRANSPORT PARAMETERS FOR SOLUTES IN SALT-TREATED SOIL COLUMNS

2017 ◽  
Vol 48 (1) ◽  
Author(s):  
Bahia & Naser
Keyword(s):  
Sodium Chloride ◽  
Calcium Chloride ◽  
Peclet Number ◽  
Dispersion Coefficient ◽  
Breakthrough Curves ◽  
Retardation Factor ◽  
Transport Parameters ◽  
Péclet Number ◽  
Mixed Salts ◽  
Sodium And Potassium

A laboratory experiment was carried out at the Department of Soil Sciences and Water Resources, College of Agriculture, University of Baghdad. Silty clay soil was treated with three salt solutions (NaCl, CaCl2 and mixed NaCl–CaCl2). Homogeneously packed soil columns (10 cm, 40 cm) were leached six times using tap water. Effluent samples were collected to determine ion concentration Cl-, Ca++, Na+, K+ and Mg++. Breakthrough curves were used to estimate solute transport parameters (retardation factor, peclet number) using an analytical solution of convection-dispersion equation (CDE) by CXTFIT program. The results showed that relative concentration of chloride was increased rapidly with calcium chloride, which increased sodium leaching rate at starting of breakthrough curve. Sodium chloride increased water requirements for calcium displacement. Results indicated a good fitting of convection-dispersion equation with breakthrough curves data. The best-fit were used to calculate peclet number, retardation factor and dispersion coefficient. When soil was treated with calcium chloride, Peclet number of chloride was increased from 3.13 to 6.48, while it has been decreased for calcium, sodium and potassium. Sodium chloride decreased peclet numbers of chloride, calcium and sodium. Also mixed salts increased sodium peclet number from 1.01 to 9.02. Results showed, calcium chloride decreased retardation factor of chloride from 1.59 to 0.50, while it has been increased from 1.39, 1.58 to 175.00, 493.36 for each of sodium and potassium, respectively. Retardation factor of calcium was decreased when soil was treated with sodium chloride or mixed salts. Dispersion coefficient was decreased for chloride, and increased for calcium and magnesium. When soil was treated with calcium chloride, dispersion coefficients have been increased from 24.29, 25.56 to 40.51, 40.89 cm2hr-1 for sodium and potassium, respectively.

scholarly journals Determination of transport parameters for heavy metal in residual compacted soil using two methodologies

2006 ◽  
Vol 33 (7) ◽  
pp. 912-917
Author(s):  
Izabel Christina Duarte Azevedo ◽  
Cleidimar Rejane Nascentes ◽  
Antonio Teixeira de Matos ◽  
Roberto Francisco de Azevedo
Keyword(s):  
Heavy Metals ◽  
Dispersion Coefficient ◽  
Soil Column ◽  
Optimization Procedure ◽  
Retardation Factor ◽  
Hydrodynamic Dispersion ◽  
Column Test ◽  
Transport Parameters ◽  
Compacted Soil ◽  
Cumulative Mass

Values of the hydrodynamic dispersion coefficient and retardation factor obtained using the traditional and cumulative mass methods of column test analysis for zinc, manganese, and cadmium in a compacted soil are compared. The soil under study is from the B horizon of a residual gneissic tropical soil used for construction of the liner for the sanitary landfill in the District of Visconde do Rio Branco, Minas Gerais (MG), Brazil. To evaluate the behavior of landfill leachate heavy metals through the soil, soil column tests were performed on samples of compacted soil. A computational program that uses an optimization procedure to generate values of the hydrodynamic dispersion coefficient and retardation factor was developed to facilitate interpretation of the results obtained by the cumulative mass method. Values of the retardation factor and hydrodynamic dispersion coefficient were not influenced by the method of determination, even when a reduced number of effluent samples was used by the cumulative mass method. The use of the cumulative mass method, based on a reduced number of pore volumes, reduces the time and cost involved in the tests.Key words: heavy metals, column test, cumulative mass method.

Consistency of the strontium transport parameters in Boom Clay obtained from different types of experiments: accounting for the filter plates

2012 ◽  
Vol 1475 ◽  
Author(s):  
Marc Aertsens ◽  
Joan Govaerts ◽  
Norbert Maes ◽  
Liesbeth Van Laer
Keyword(s):  
Diffusion Coefficient ◽  
Apparent Diffusion Coefficient ◽  
Tritiated Water ◽  
Capacity Factor ◽  
Retardation Factor ◽  
Transport Parameters ◽  
Boom Clay ◽  
Different Types ◽  
Apparent Diffusion ◽  
Through Diffusion

ABSTRACTIn a previous MRS paper, the consistency of migration parameters for strontium (Sr) in Boom Clay, obtained by different types of experiments, was examined. No consistent value could be obtained for the product ηR of the diffusion accessible porosity η and the retardation factor R. Furthermore the nearly flat concentration profile measured in one of the through diffusion experiments could not be explained by the traditional through diffusion model. A reason is that the filter plates confining the clay sample have not been taken into account.Therefore, for Sr and tritiated water (HTO), the apparent diffusion coefficient and the product ηR in the filters are measured in through diffusion experiments on filter plates.Taking into account the filter plates, the outlet fluxes and the Sr profiles in the clay of both Sr through diffusion experiments, are described well with (i) the previously estimated Sr apparent diffusion coefficient in the clay of 7 × 10-12 m2/s, (ii) an apparent filter diffusion coefficient in the range 2 × 10-12 m2/s to 5 × 10-11 m2/s (vs. 1 × 10-11 m2/s measured in the filter through diffusion experiments), (iii) a clay capacity factor ηR in the range between 5000 and 22000, and (iv) a filter capacity factor between 0.3 and 0.6 (in agreement with the filter through diffusion measurements). However, using the above parameters, the evolution at the inlet could not be described. So although inconsistency diminished, some inconsistency remains.

Organophosphorus Compounds. I. 2-Chloroalkylphosphonic Acids as Phosphorylating Agents

1963 ◽  
Vol 16 (4) ◽  
pp. 596 ◽  
Author(s):  
JA Maynard ◽  
JM Swan
Keyword(s):  
Magnetic Resonance ◽  
Proton Magnetic Resonance ◽  
Organophosphorus Compounds ◽  
Chloride Ion ◽  
The Other ◽  
High Yield ◽  
Neutral Solution ◽  
Phosphate Ion ◽  
Phosphorus Containing ◽  
Group 2

Alcohols and phenols are phosphorylated in high yield by reaction with various 2-chloroalkylphosphonic acids at 20-50�C in the presence of three or more molar equivalents of cyclohexylamine or triethylamine, the other products being the corresponding alk-1-ene and chloride ion. The reaction probably proceeds by attack of an ROH molecule on the phosphorus atom of a doubly-ionized phosphonate group. 2-Chlorodecyl-, 10-carboxy-2-chlorodecyl-, and 2-chloro-octylphosphonic acid decompose rapidly in neutral solution giving chloride ion, phosphate ion, and the corresponding alk-1-ene. In the absence of hydroxylic compounds, 2-chlorodecylphosphonic acid is decomposed by cyclohexylamine to dec-1-ene and a product which appears to be N-cyclohexylphosphoramidate; t-amines and also aniline cause dehydrohalogenation to dec-1-enylphosphonic acid. The proton magnetic resonance spectra of most of the phosphorus-containing substances described herein are recorded.

scholarly journals Geochemical studies of surface bottom sediments and soils of small watercourses

2020 ◽  
Vol 169 ◽  
pp. 01005
Author(s):  
Evgeni Nesterov ◽  
Timofei Belyakov ◽  
Stanislav Dubrova ◽  
Pavel Egorov
Keyword(s):  
Bottom Sediments ◽  
Analytical Data ◽  
Laboratory Data ◽  
Petroleum Products ◽  
Ammonium Nitrogen ◽  
Polluted Soils ◽  
Phosphate Ion ◽  
Nickel Zinc ◽  
Sources Of Pollution ◽  
Geochemical Studies

Analytical data on samples of bottom sediments of the Novaya river watercourse made it possible to identify areas of pollution, sources of pollution and determine the nature of the influence of the anthropogenic factor on the state of the river. It was found that bottom sediments are divided into slightly polluted, moderately polluted, and dangerously polluted. Soils on the total indicator of pollution belong to the permissible category. The list of defined indicators includes: hydrogen index (pH), total metal content (cadmium, copper, lead, mercury, nickel, zinc), arsenic, petroleum products, benz(a)pyrene, ammonium nitrogen, phosphate ion, organic matter. Based on the results of the interpretation of the laboratory data, it was found that in accordance with the Regional standard, the precipitation the majority of samples are slightly polluted; at some samples, are moderately polluted; at a quarter of samples are dangerously polluted.

scholarly journals Determination of the sodium retardation factor using different methods: Analysis of their characteristics and impact on the solute movement prediction in a structured Brazilian soil

2018 ◽  
Vol 22 (4) ◽  
pp. 281-289
Author(s):  
Vanessa Godoy ◽  
Gian Franco Napa-García ◽  
Lázaro Zuquette
Keyword(s):  
Prediction Models ◽  
Breakthrough Curves ◽  
Retardation Factor ◽  
Determination Method ◽  
Transport Parameters ◽  
Undisturbed Soil ◽  
Analytical Analysis ◽  
Initial Concentration ◽  
Preferential Pathways ◽  
The Impact

The retardation factor (Rd) is one of the main important solute transport parameters. Its value can vary significantly depending on the method used for its determination. In this paper, the sodium Rd is experimentally determined using undisturbed sandy columns to compare four methods of Rd determination and assess the impact of the chosen method in the prediction of sodium movement. Column experiments in undisturbed soil columns and analytical analysis were performed. The results showed that the soil has dual-porosity and preferential pathways. The breakthrough curves were in accordance with the soil’s physical characteristics. The Rd values ranged from 1.7 to 7.77 depending on the initial concentration and on the method used. These differences arise from the conceptual model of each Rd determination method. The experimental and analytical analysis indicated that the higher the Rd, the slower the movement. The methods that best reproduced the laboratory sodium movement were Ogata and Banks’ (1961), and Langmuir and Freundlich’s isotherms. The prediction models presented smaller errors with the increase of the initial concentration. In these cases, the predicted concentrations can be overestimated up to 22.5 % when using a not suitable method. Hence these results suggest that the Rd determination method can strongly affect the prediction of the sodium movement. Because of that, it is of vital importance to evaluate each method and how they can be adequate to the soil under investigation when determining Rd.

scholarly journals A Laboratory Based Study On The Movement Of Radiocaesium In Some Soil Columns By Gamma Spectrometer

1970 ◽  
Vol 35 (2) ◽  
pp. 141-151 ◽  
Author(s):  
MM Haque ◽  
S Ghose ◽  
SMA Islam
Keyword(s):  
Diffusion Coefficient ◽  
Natural Radionuclides ◽  
Soil Column ◽  
Liquid Radioactive Waste ◽  
Clay Content ◽  
Vertical Movement ◽  
Soil Samples ◽  
Retardation Factor ◽  
Transport Parameters ◽  
Nuclear Facilities

The fate and movement of 137Cs in different types of soil profiles of Chittagong City and Ishwardi Upazila of Bangladesh were investigated with laboratory based column method by γ-spectrometer. The diffusion coefficient, distribution coefficient and retardation factors of 137Cs were measured. The physio-chemical characteristics and radioactive concentration of natural radionuclides of the soil samples were also measured. The maximum diffusion coefficient was found 2.06 X 10-5 cm2/s in the investigated soils. The vertical movement of 137Cs in those soil samples found to be slow. Maximum of clay content corresponded with the maximum of retardation factor and with the minimum of diffusion coefficient. This experimental findings demonstrated that caesium is strongly absorbed in soil particles and therefore, do not pose any threat to ground water contamination by the approximated future accidental release of 137Cs in the study area. Moreover, the locally available clay can be used as an adsorbent for the decontamination of liquid radioactive waste generated at nuclear facilities without any pretreatment. Key words: Radioisotopes; Physio-chemical; Transport parameters; Soil column DOI: http://dx.doi.org/10.3329/jbas.v35i2.9417 JBAS 2011; 35(2): 141-151

scholarly journals RESIDUAL ACTIVITY OF HERBICIDES APPLIED TO COTTON ON CROPS CULTIVATED IN SUCCESSION

2016 ◽  
Vol 29 (1) ◽  
pp. 143-152 ◽  
Author(s):  
ELIEZER ANTONIO GHENO ◽  
RUBEM SILVÉRIO DE OLIVEIRA JUNIOR ◽  
JAMIL CONSTANTIN ◽  
HUDSON KAGUEYAMA TAKANO ◽  
ALEXANDRE GEMELLI
Keyword(s):  
Residual Activity ◽  
The Other ◽  
Residual Effects ◽  
Herbicide Application ◽  
Carryover Effects ◽  
Control Applications ◽  
Significant Damage ◽  
Crop Development ◽  
Herbicide Treatments ◽  
Time Periods

ABSTRACT: Herbicides with high persistence in soil can cause problems for crops sown in succession to their application. Thus, the aim of this study was to estimate, in greenhouse conditions, the safe period of time after application of preemergent herbicides used on cotton crops (isolated or in mixtures) for the crops grown in succession (bean, corn, and soybean). The experimental design was completely randomized in a factorial scheme (5 x 11) + 1, with five repetitions. For each experiment, treatments combined different time periods between herbicide application and sowing of crops (280, 210, 140, 70, and 0 days before sowing of crops) with eleven herbicide treatments: fomesafen (625 g ha-1) prometryne (1250 g ha-1), diuron (1250 g ha-1), S-metolachlor (768 g ha-1), clomazone (1000 g ha-1), fomesafen + prometryne (625 + 1250 g ha-1), fomesafen + diuron (625 + 1250 g ha-1), fomesafen + S-metolachlor (625 + 768 g ha-1), fomesafen + clomazone (625 + 1000 g ha-1), fomesafen + clomazone + diuron (625 + 1000 + 1250 g ha-1), and fomesafen + clomazone + prometryne (625 + 1000 + 1250 g ha-1), plus an untreated control. Applications of diuron showed the greatest persistence, causing the largest carryover effects for the three crops evaluated. The other treatments showed residual effects or affected crop development when sowings were performed up to 70 days after application. At later periods no significant damage was observed.

scholarly journals Migration of Chromium Through Black Cotton Soil Amended with Ground Granular Blast Furnace Slag

2019 ◽  
Vol 8 (4) ◽  
pp. 8197-8201
Keyword(s):  
Blast Furnace ◽  
Hydraulic Conductivity ◽  
Blast Furnace Slag ◽  
Soil Column ◽  
Retardation Factor ◽  
Black Cotton Soil ◽  
Transport Parameters ◽  
Breakthrough Time ◽  
Granulated Blast Furnace Slag ◽  
Furnace Slag

The aim of this work is to assess the suitability the locally available black cotton soil amended with industrial waste material such as blast furnace slag in the context of using them as liner materials. The black cotton soil (BCS) and Ground Granulated Blast furnace Slag (GGBS) are mixed in three ratios, 90:10, 80:20 and 70:30 and hydraulic conductivity of these mixtures have been tested using falling head method. The hydraulic conductivity of soil with 30% GGBS is the lowest and satisfies the hydraulic conductivity criteria of 10-7 cm/s or less for liner application. Soil column tests are conducted to determine the transport parameters of chromium through the optimized soil mixture. The transport parameters of chromium through optimized mixture was found to be diffusion coefficient D = 3.9x10-6 cm2/s and retardation factor R = 4.964. BCS with 30% GGBS mixture with a hydraulic gradient of 0.3 and can be used as liner to contain chromium ion as it gives a breakthrough time of more than 100 years for a liner thickness of 1m.

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