The broad application and mechanism of humic acids for treating environmental pollutants: Insights from bibliometric analysis

Emergent functional behaviour of humic substances perceived as complex labile aggregates of small organic molecules and oligomers

Environmental Chemistry ◽

10.1071/en19095 ◽

2019 ◽

Vol 16 (7) ◽

pp. 505 ◽

Cited By ~ 3

Author(s):

Elena A. Vialykh ◽

Dennis R. Salahub ◽

Gopal Achari ◽

Robert L. Cook ◽

Cooper H. Langford

Keyword(s):

Small Molecules ◽

Humic Substances ◽

Humic Acids ◽

Organic Contaminants ◽

Environmental Pollutants ◽

Computational Modelling ◽

Chemical Properties ◽

Stacking Interactions ◽

Aggregation Process ◽

Π Stacking

Environmental contextThe correlation of physicochemical characteristics of humic substances with their function is crucial to our understanding of how environmental pollutants interact with humic substances. We have developed an approach that models emergent functions of fulvic and humic acids depending on sample characteristics. The results will be useful for predicting the sequestration of organic contaminants in soil under various conditions. AbstractThe structural organisation of humic substances (HS) has been a central question of earth sciences for several decades. The latest experimental results have led to the recognition of HS as complex mixtures of small molecules and oligomers. We investigate the correlation between the chemical composition of HS, perceived as labile aggregates, and the emergent functions. Computational modelling was used to help to understand the processes and mechanisms on the molecular scale that occur in different fractions of the HS, fulvic acids (FA) and humic acids (HA), as they interact with metal ions and organic pollutants. The importance of non-covalent interactions in the emergent functions of HS is highlighted. H-bonding, hydrophilic/hydrophobic surface areas and π-stacking interactions play a significant role in aggregation processes as well as in the sorption of environmental pollutants. In a highly hydrophilic system with small molecules (the SRFA-22 model), H-bonding is the main force that drives the aggregation process. However, in a highly aromatic and hydrophobic model with larger molecular fragments (SRHA-6), hydrophobic and π-stacking interactions dominate in the aggregation process. The chemical properties of contaminants significantly affect their mechanisms of sorption by HS. The interaction of a polar pollutant, phenol, with HS occurs through H-bonding, whereas non-polar benzene interacts through hydrophobic and π-stacking interactions. The non-polar pollutant results in a much stronger sorption by HS and causes an additional structural rearrangement of the aggregates, which make it more stable in the environment.

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Polychlorinated biphenyl induced hepatocyte alterations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012789x ◽

1987 ◽

Vol 45 ◽

pp. 716-717

Author(s):

D.N. Collins ◽

J.N. Turner ◽

K.O. Brosch ◽

R.F. Seegal

Keyword(s):

Lipid Droplets ◽

Wistar Rats ◽

Homovanillic Acid ◽

Polychlorinated Biphenyl ◽

Corn Oil ◽

Environmental Pollutants ◽

Short Term ◽

Pcb Congeners ◽

Urinary Levels ◽

The Brain

Polychlorinated biphenyls (PCBs) are a ubiquitous class of environmental pollutants with toxic and hepatocellular effects, including accumulation of fat, proliferated smooth endoplasmic recticulum (SER), and concentric membrane arrays (CMAs) (1-3). The CMAs appear to be a membrane storage and degeneration organelle composed of a large number of concentric membrane layers usually surrounding one or more lipid droplets often with internalized membrane fragments (3). The present study documents liver alteration after a short term single dose exposure to PCBs with high chlorine content, and correlates them with reported animal weights and central nervous system (CNS) measures. In the brain PCB congeners were concentrated in particular regions (4) while catecholamine concentrations were decreased (4-6). Urinary levels of homovanillic acid a dopamine metabolite were evaluated (7).Wistar rats were gavaged with corn oil (6 controls), or with a 1:1 mixture of Aroclor 1254 and 1260 in corn oil at 500 or 1000 mg total PCB/kg (6 at each level).

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Computers and Iatrocomplexities

Methods of Information in Medicine ◽

10.1055/s-0038-1636284 ◽

1966 ◽

Vol 05 (04) ◽

pp. 167-171 ◽

Cited By ~ 5

Author(s):

L. E. Faer

Keyword(s):

Twentieth Century ◽

Cigarette Smoke ◽

Environmental Pollutants ◽

Genetic Composition ◽

Koch’S Postulates ◽

Lung Malignancies ◽

Causative Agents ◽

Disease Study ◽

Multiple Etiology ◽

Great Advance

Developments of disease hypotheses and conceptions of disease as philosophic entities have shown bursts of great advance. One just concluded includes emergence of bacteriology and virology culminating in Koch’s Postulates, which in the twentieth century were primary bases for disease study and colored all approaches to medicine.With recent extraordinary advances in technology, medicine faces great new obligations demanding fresh approaches and untrammeled thinking for solution of problems posed. It is clear that any approach to diseases and disabilities induced by exposures to environmental pollutants must take multiple etiology into account. For example, contributing to causation of lung malignancies one must list usual dusts, radioactivity, smog, auto exhausts, cigarette smoke and genetic composition. Consideration of plural factors in genesis of environmentally associated disease leads to the hypothesis of the incremental insult, a complex and difficult conception in which must be included provision for multiple causative agents, each contributing but a fraction toward total etiology^ Computers developed to their present refinement provide necessary tools for whatever complexity required to spawn and fructify hypotheses of inter-relating associations of incremental insults leading to pathology.

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The Therapeutic and Diagnostic Value of Fluorine

Scientific Inquiry and Review ◽

10.32350/sir.41.02 ◽

2020 ◽

Vol 4 (1) ◽

pp. 17-29

Author(s):

Isma Attique ◽

Shabbir Hussain ◽

Muhammad Amjad ◽

Khalida Nazir ◽

Muhammad Shahid Nazir

Keyword(s):

Anticancer Agent ◽

Chemotherapeutic Agent ◽

Functional Materials ◽

Diagnostic Value ◽

Vital Role ◽

Malignant Growth ◽

Medical Field ◽

Active Nucleus ◽

Broad Application ◽

Tracer Atom

Fluorine has a useful positron transmitting isotope and it enjoys broad application in the medical field. It is utilized in fluorinated agents,therapeutic sciences and steroid field. Fluorine incorporation viafluoroalkylation is a useful approach in the development of new functional materials and in drug design. Fluorine also plays its role as an anticancer agent and is a successful chemotherapeutic agent for certain sorts of malignant growth. 5-fluorouracil plays a vital role in the treatment of cancer. 18 Facts as a radio label tracer atom in PET imaging. 19 F has the second most sensitive and stable NMR-active nucleus.

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

Anbar Journal of Agricultural Sciences ◽

10.32649/ajas/2020/2 ◽

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.

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