ROLE OF ADDED PHOSPHOGYPSUM AND HUMIC ACIDS IN THE KINETIC RELEASE OF SALT FROM SALT AFFECTED SOIL (SALINE – SODIC)

2020 ◽  
pp. 15-27
Keyword(s):  
Electrical Conductivity ◽  
Humic Acids ◽  
Release Rate ◽  
Release Kinetics ◽  
Sodium Adsorption Ratio ◽  
Salt Affected Soil ◽  
Two Factors ◽  
Dissolved Ions ◽  
Kinetic Release

In order to study the effect of phosphogypsum and humic acids in the kinetic release of salt from salt-affected soil, a laboratory experiment was conducted in which columns made from solid polyethylene were 60.0 cm high and 7.1 cm in diameter. The columns were filled with soil so that the depth of the soil was 30 cm inside the column, the experiment included two factors, the first factor was phosphogypsum and was added at levels 0, 5, 10 and 15 tons ha-1 and the second-factor humic acids were added at levels 0, 50, 100 and 150 kg ha-1 by mixing them with the first 5 cm of column soil and one repeater per treatment. The continuous leaching method was used by using an electrolytic well water 2.72 dS m-1. Collect the leachate daily and continue the leaching process until the arrival of the electrical conductivity of the filtration of leaching up to 3-5 dS m-1. The electrical conductivity and the concentration of positive dissolved ions (Ca, Mg, Na) were estimated in leachate and the sodium adsorption ratio (SAR) was calculated. The results showed that the best equation for describing release kinetics of the salts and sodium adsorption ratio in soil over time is the diffusion equation. Increasing the level of addition of phosphogypsum and humic acids increased the constant release velocity (K) of salts and the sodium adsorption ratio. The interaction between phosphogypsum and humic acids was also affected by the constant release velocity of salts and the sodium adsorption ratio. The constant release velocity (K) of the salts and the sodium adsorption ratio at any level of addition of phosphogypsum increased with the addition of humic acids. The highest salts release rate was 216.57 in PG3HA3, while the lowest rate was 149.48 in PG0HA0. The highest release rate of sodium adsorption ratio was 206.09 in PG3HA3, while the lowest rate was 117.23 in PG0HA0.

scholarly journals CALICUM, Mg AND Na RELEASE KINETICS FROM SALINE- SODIC SOIL MIXED WITH SOME AMENDMENTS

2020 ◽  
Vol 51 (6) ◽  
pp. 1694-1705
Author(s):  
Al-Hadethi & Al-Alwani
Keyword(s):  
Humic Acids ◽  
Release Kinetics ◽  
Soil Column ◽  
Sodium Adsorption Ratio ◽  
Water Soluble ◽  
Soil Columns ◽  
Sodic Soil ◽  
Two Factors ◽  
Na Release ◽  
Kinetics Of

This study was aimed to investigate the effect of phosphogypsum and humic acids on the leaching and releasing of salts from saline- sodic soil. A laboratory experiment was conducted in polyethylene columns (60.0 cm and 7.1 cm). The columns were filled with 30 cm soil (EC=73.78 dSm-1). The experiment included two factors, phosphogypsum added at levels 0, 5, 10 and 15 mtons ha-1 with symbols PG0,PG1, PG2 and PG3 respectively, and humic acids were added at levels 0, 50, 100 and 150 kg ha-1 with symbols HA0, HA1, HA2 and HA3, mixing them with the top 5 cm of soil column. The electrical conductivity and the concentrations of water soluble cations (Ca, Mg, and Na) in leachate were determined and sodium adsorption ratio (SAR) was calculated. Results showed that accumulative salts (TDS), sodium released from soil columns increased with increasing the level of addition, whether of phosphogypsum or humic acids. The highest value of salts and sodium released was 682.63 g L-1 and 7086.12 mmol L-1 respectively in the treatment PG3HA3, while the lowest value was 455.94 g L-1 and 3899.40 mmol L-1 respectively in the treatment PG0HA0. Calcium (mmol L-1) increased by increasing the level of phosphogypsum, decreased by increasing the level of humic acids, the highest value of accumulated calcium was 1599.0 mmol L-1 in PG3HA0 while the lowest value was 820.53 mmol L-1 in PG0HA3. The results showed that the best equation for describing release kinetics of sodium adsorption ratio in soil is the diffusion equation. Increasing level of phosphogypsum and humic acids increased the release constant velocity (K) of sodium adsorption ratio.

Growth and Mineral Nutrition in Salt Stressed Guava ( Psidium guajava L.) cv . Allahabad Safeda

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
ANSHUMAN SINGH ◽  
ASHWANI KUMAR ◽  
R.K. YADAV ◽  
ASHIM DUTTA ◽  
D.K. SHARMA
Keyword(s):  
Electrical Conductivity ◽  
Chemical Composition ◽  
Plant Height ◽  
Salinity Tolerance ◽  
Soil Ph ◽  
High Salinity ◽  
Psidium Guajava ◽  
Sodium Adsorption Ratio ◽  
Saline Soils ◽  
Experimental Soil

Guav a cv . Allahabad Safeda w as grown in saline soils and irrigated with the best av ailable w ater -1 -1 + -1 (EC 2.8 dS m ). Based on chemical composition (pH- 7.1, EC - 2.8 dS m , Na - 20.04 meq l and IW IW sodium adsorption ratio- 4.86), irrigation w ater w as categorized as marginally saline. The soil pH 2 -1 w as mostly below 8.5 but mean electrical conductivity (EC ) v alues ranged from 0.5-2 dS m 2 indicating moderate to high salinity in the experimental soil. After one-y ear of experimentation, fiv e plants randomly selected from each treatment and the data w ere recorded. Plant height -1 -1 significantly increased (LSD 5%) with increase in salinity from 0.5 dS m to 1.4 dS m . A similar -1 trend w as noted with respect to stem girth. The av erage plant height at 0.5, 0.9 and 1.4 dS m salinity lev els w as 98.3 cm, 108.3 cm and 123 cm, respectiv ely whereas the corresponding stem girth v alues -1 w ere 2.24 cm, 2.28 cm and 2.46 cm. At 2 dS m salinity ,how ev er , both av erage plant height (94.6 cm) and stem girth (2.24 cm) significantly decreased and w ere found to be comparable to control (0.5 dS -1 + -1 m ) v alues. Plants show ed negligible Na accumulation in leav es up to 1.4 dS m salinity , but -1 + exposure to elev ated salinity (2 dS m ) significantly increased leaf Na (0.16% DW). These data -1 indicated a salinity tolerance (EC )threshold of about 1.5 dS m inguav a cultiv ar Allahabad Safeda.

scholarly journals An Overview of Adipose Tissue ACE2 Modulation by Diet and Obesity. Potential Implications in COVID-19 Infection and Severity

2021 ◽  
Vol 22 (15) ◽  
pp. 7975
Author(s):  
Saioa Gómez-Zorita ◽  
Iñaki Milton-Laskibar ◽  
Laura García-Arellano ◽  
Marcela González ◽  
María P. Portillo
Keyword(s):  
Adipose Tissue ◽  
Protective Role ◽  
Inflammatory Factors ◽  
Current Evidence ◽  
Disease Outcomes ◽  
Lower Activation ◽  
Two Factors ◽  
Obese Subjects ◽  
Ace2 Gene

The present review is aimed at analysing the current evidence concerning the potential modulation of obesity and/or diet in adipose tissue ACE2. Additionally, the potential implications of these effects on COVID-19 are also addressed. The results published show that diet and obesity are two factors that effectively influence the expression of Ace2 gene in adipose tissue. However, the shifts in this gene do not always occur in the same direction, nor with the same intensity. Additionally, there is no consensus regarding the implications of increased adipose tissue ACE2 expression in health. Thus, while in some studies a protective role is attributed to ACE2 overexpression, other studies suggest otherwise. Similarly, there is much debate regarding the role played by ACE2 in COVID-19 in terms of degree of infection and disease outcomes. The greater risk of infection that may hypothetically derive from enhanced ACE2 expression is not clear since the functionality of the enzyme seems to be as important as the abundance. Thus, the greater abundance of ACE2 in adipose tissue of obese subjects may be counterbalanced by its lower activation. In addition, a protective role of ACE2 overexpression has also been suggested, associated with the increase in anti-inflammatory factors that it may produce.

scholarly journals Halloysite nanotubes filled with salicylic acid and sodium diclofenac: effects of vacuum pumping on loading and release properties

2021 ◽  
Author(s):  
Lorenzo Lisuzzo ◽  
Giuseppe Cavallaro ◽  
Stefana Milioto ◽  
Giuseppe Lazzara
Keyword(s):  
Salicylic Acid ◽  
Release Kinetics ◽  
Halloysite Nanotubes ◽  
Drug Molecules ◽  
Sodium Diclofenac ◽  
Tunable Release ◽  
Feature Based ◽  
Kinetics Of ◽  
Filling Mechanism

AbstractIn this work, we investigated the effects of the vacuum pumping on both the loading efficiencies and the release kinetics of halloysite nanotubes filled with drug molecules dissolved in ethanol. As model drugs, salicylic acid and sodium diclofenac were selected. For comparison, the loading of the drug molecules was conducted on platy kaolinite to explore the key role of the hollow tubular morphology on the filling mechanism of halloysite. The effects of the pressure conditions used in the loading protocol were interpreted and discussed on the basis of the thermodynamic results provided by Knudsen thermogravimetry, which demonstrated the ethanol confinement inside the halloysite cavity. Several techniques (TEM, FTIR spectroscopy, DLS and $$\zeta$$ ζ -potential experiments) were employed to characterize the drug filled nanoclays. Besides, release kinetics of the drugs were studied and interpreted according to the loading mechanism. This work represents a further step for the development of nanotubular carriers with tunable release feature based on the loading protocol and drug localization into the carrier. Graphic abstract The filling efficiency of halloysite nanotubes is enhanced by the reduction of the pressure conditions used in the loading protocol.

scholarly journals The Role of Emotionality and Power on Tendency to Unethical Behaviors

2012 ◽  
Vol 2 (4) ◽  
pp. 187
Author(s):  
Hossein Safarzadeh ◽  
Alireza Soloukdar ◽  
Ali Alipour ◽  
Seyedeh Akram Parpanchi
Keyword(s):  
Correlation Coefficient ◽  
Organizational Citizenship ◽  
Significant Relationship ◽  
Independent Variables ◽  
Ethical Behaviors ◽  
Two Factors ◽  
Unethical Behaviors ◽  
The Common ◽  
Two Independent Variables

Emotion and power have been studied very deeply especially during the last decade; however, the common effects of these two factors on individuals' optional behaviors (organizational citizenship, anti-productivity, unethical behaviors) have been less focused. In the present paper, the role of individuals' emotionality, their interest in power, and their tendency to unethical behaviors will be discussed according to the model of Levine. Three questionnaires were distributed and the collected data were analyzed using Pearson’s Correlation Coefficient, Multiple Regression, and T- test. Findings indicated that there is a significant relationship between the two independent variables of emotionality and power and tendency to unethical behaviors. Moreover, according to the results of the tests, men are more emotion-oriented and power seekers than women. Keywords: Power, Emotion, Ethical Behaviors

Brothers or others in arms? Civilian constituencies and rebel fragmentation in civil war

2017 ◽  
Vol 55 (1) ◽  
pp. 62-77 ◽  
Author(s):  
Eric S Mosinger
Keyword(s):  
Social Networks ◽  
Regression Analysis ◽  
Collective Action ◽  
Diffusion Model ◽  
Theoretical Framework ◽  
Quantitative Evidence ◽  
Rebel Groups ◽  
Two Factors ◽  
Cross National

Why do united rebel fronts emerge in some insurgencies, while in other insurgencies multiple rebel groups mobilize independently to challenge the state, and often, each other? I develop a diffusion model of rebel fragmentation in which participation in rebellion spreads, completely or incompletely, through networks of civilians and dissidents. Using this theoretical framework I hypothesize that two factors jointly determine whether a rebel movement remains unified or fragments: the rebels’ investment in civilian mobilization, and the overall level of civilian grievances. The theory predicts that widely shared grievances motivate the formation of many small dissident groups willing to challenge the regime. Given the difficulty of collective action between disparate opposition actors, an emerging rebel movement will tend towards fragmentation when popular grievances are high. Yet extremely high civilian grievances can also help rebels activate broad, overlapping civilian social networks that serve to bridge together dissident groups. Mass-mobilizing rebel groups, benefiting from the participation of broad civilian networks, are most likely to forge and maintain a unified rebel front. I test this theory alongside several alternatives drawn from cross-national studies of conflict using regression analysis. The quantitative evidence lends considerable credence to the role of rebel constituencies in preventing or fomenting rebel fragmentation.

scholarly journals Using hydraulic head, chloride and electrical conductivity data to distinguish between mountain-front and mountain-block recharge to basin aquifers

2018 ◽  
Vol 22 (2) ◽  
pp. 1629-1648 ◽  
Author(s):  
Etienne Bresciani ◽  
Roger H. Cranswick ◽  
Eddie W. Banks ◽  
Jordi Batlle-Aguilar ◽  
Peter G. Cook ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Arid Regions ◽  
South Australia ◽  
Hydraulic Head ◽  
Mountain Front ◽  
Quaternary Aquifers ◽  
Groundwater Systems ◽  
Flow Directions ◽  
Electrical Conductivity Data

Abstract. Numerous basin aquifers in arid and semi-arid regions of the world derive a significant portion of their recharge from adjacent mountains. Such recharge can effectively occur through either stream infiltration in the mountain-front zone (mountain-front recharge, MFR) or subsurface flow from the mountain (mountain-block recharge, MBR). While a thorough understanding of recharge mechanisms is critical for conceptualizing and managing groundwater systems, distinguishing between MFR and MBR is difficult. We present an approach that uses hydraulic head, chloride and electrical conductivity (EC) data to distinguish between MFR and MBR. These variables are inexpensive to measure, and may be readily available from hydrogeological databases in many cases. Hydraulic heads can provide information on groundwater flow directions and stream–aquifer interactions, while chloride concentrations and EC values can be used to distinguish between different water sources if these have a distinct signature. Such information can provide evidence for the occurrence or absence of MFR and MBR. This approach is tested through application to the Adelaide Plains basin, South Australia. The recharge mechanisms of this basin have long been debated, in part due to difficulties in understanding the hydraulic role of faults. Both hydraulic head and chloride (equivalently, EC) data consistently suggest that streams are gaining in the adjacent Mount Lofty Ranges and losing when entering the basin. Moreover, the data indicate that not only the Quaternary aquifers but also the deeper Tertiary aquifers are recharged through MFR and not MBR. It is expected that this finding will have a significant impact on the management of water resources in the region. This study demonstrates the relevance of using hydraulic head, chloride and EC data to distinguish between MFR and MBR.

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