Desorption Kinetics and Difference in Removal Enhancement of PAHs in Aged Soils by Tween 80

The desorption process and desorption rate is an important factor that influence the bioavailability and remediation efficiency. PAH contaminated soils from former Beijing coking plant are remediated by Tween 80 solution. Desorption kinetics and efficiency enhancement of PAHs by Tween 80 are investigated in this paper. Results show that (1) For the relatively water-insoluble PAHs with high molecular weight, the time needed for desorption equilibrium is longer than that of relatively water-soluble PAHs with low molecular weight. The desorption kinetics of PAHs fit better to Elovich equation than to the first-order kinetics equation, especially for the PAHs with 4-6 ring numbers, which means that the desorption of PAHs from soil is an heterogeneous diffusion process; (2) Due to the severe sorption loss of Tween 80, and the difficulty in removing PAHs from aged contaminated soils, Tween 80 solution at a concentration of 5000 mg/L can only remove the PAHs with efficiencies of 11.31-18.23%. The desorption enhancement of PAHs is 7.62-14.04%, with the values of 4-6 ring number bigger than that of 2-3 ring number, which indicated that surfactant is more favorable to the desorption of PAHs with more ring numbers and thus more hydrophobic.

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Environmental Impacts and Immobilization Mechanisms of Cadmium, Lead and Zinc in Geotechnical Composites Made from Contaminated Soil and Paper-Ash

Applied Sciences ◽

10.3390/app112411822 ◽

2021 ◽

Vol 11 (24) ◽

pp. 11822

Author(s):

Marija Đurić ◽

Primož Oprčkal ◽

Vesna Zalar Serjun ◽

Alenka Mauko Pranjić ◽

Janez Ščančar ◽

...

Keyword(s):

Contaminated Soil ◽

Contaminated Soils ◽

Methodological Approach ◽

Extraction Procedure ◽

Water Soluble ◽

Mineral Phases ◽

Lead And Zinc ◽

Remediation Efficiency ◽

Cadmium Lead ◽

One Year

Paper-ash is used for remediation of heavily contaminated soils with metals, but remediation efficiency after longer periods has not been reported. To gain insights into the mechanisms of immobilization of cadmium (Cd), lead (Pb), and znic (Zn), a study was performed in the laboratory experiment in uncontaminated, artificially contaminated, and remediated soils, and these soils treated with sulfate, to mimic conditions in contaminated soil from zinc smelter site. Remediation was performed by mixing contaminated soil with paper-ash to immobilize Cd, Pb, and Zn in the geotechnical composite. Partitioning of Cd, Pb, and Zn was studied over one year in seven-time intervals applying the sequential extraction procedure and complementary X-ray diffraction analyses. This methodological approach enabled us to follow the redistribution of Cd, Pb, and Zn over time, thus, to studying immobilization mechanisms and assessing the remediation efficiency and stability of newly formed mineral phases. Cd, Pb, and Zn were effectively immobilized by precipitation of insoluble hydroxides after the addition of paper-ash and by the carbonization process in insoluble carbonate minerals. After remediation, Cd, Pb, and Zn concentrations in the water-soluble fraction were well below the limiting values for inertness: Cd by 100 times, Pb by 125 times, and Zn by 10 times. Sulfate treatment did not influence the remediation efficiency. Experimental data confirmed the high remediation efficiency and stability of insoluble Cd, Pb, and Zn mineral phases in geotechnical composites.

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Influence of Triton X-100 and SDBS on the Sorption of Streptomycin Sulfate from Soil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.186 ◽

2012 ◽

Vol 610-613 ◽

pp. 186-189

Author(s):

Hong Mei Zhao ◽

Yong Li Liang ◽

Wen Yan Zhao

Keyword(s):

Anionic Surfactant ◽

Contaminated Soils ◽

Soil Washing ◽

Distribution Coefficients ◽

Water Soluble ◽

Streptomycin Sulfate ◽

Surfactant Solutions ◽

Remediation Efficiency ◽

Triton X ◽

The Impact

Although surfactants have been considered in surfactant-aided soil washing systems, there is little information on the adsorption of the impact of surfactant on the adsorption of antibiotic, and this may have signiﬁcant implications for the soil. In this study, Triton X-100 and SDBS were selected to study its effect on the sorption of Streptomycin sulfate from soil under equilibrium sorption. The adsorption of Streptomycin sulfate on soils in surfactant free and surfactant solutions of different critical micelle concentrations (CMCs) has been studied .The applied surfactant concentrations (X) ranged from below the (nominal) CMC to 5 times the CMC. For relatively water-soluble Streptomycin sulfate, the distribution coefﬁcients with anionic surfactant (Kd*) deceeded those without surfactant (Kd), while non-ionic (Kd*) all exceeded those without surfactant (Kd). The Kd*/Kd ratios were used to evaluate the efficiency of surfactants and it was found that anionic surfactant is a better choice for remediation of contaminated soils whereas non-ionic surfactants leads to poor remediation efficiency.

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ANALISA KANDUNGAN BETA-GLUKAN LARUT AIR DAN LARUT ALKALI DARI TUBUH BUAH JAMUR TIRAM (Pleurotus ostreatus) DAN SHIITAKE (Lentinus edodes)

Jurnal Sains dan Teknologi Indonesia ◽

10.29122/jsti.v13i3.894 ◽

2013 ◽

Vol 13 (3) ◽

Author(s):

Netty Widyastuti ◽

Teguh Baruji ◽

Henky Isnawan ◽

Priyo Wahyudi ◽

Donowati Donowati

Keyword(s):

Molecular Structure ◽

Molecular Weight ◽

Immune System ◽

Pleurotus Ostreatus ◽

Water Soluble ◽

Low Molecular Weight ◽

Lentinus Edodes ◽

Beta Glucan ◽

Oyster Mushrooms ◽

The Difference

Beta glucan is a polysaccharide compound, generally not soluble inwater and resistant to acid. Beta glucan is used as an immunomodulator (enhancing the immune system) in mammals is usually a beta-glucan soluble in water, easily absorbed and has a low molecular weight. Several example of beta-glucan such as cellulose (β-1 ,4-glucan), lentinan (β-1 0.6-glucan) and (β-1 ,3-glucan), pleuran (β-1, 6 and β-1 ,3-glucan) are isolated from species of fungi Basidiomycota include mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes).The purpose of thisresearch activity is to obtain beta-glucan compound that can be dissolved in water and in alkali derived from fungi Basidiomycota, i.e, Oyster mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes). The result of beta-glucan compared to characterize the resulting beta glucan that is molecular structure . The difference of beta glucan extraction is based on the differences in solubility of beta-glucan. Beta glucan could be water soluble and insoluble water.

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Molecular weight-dependent abundance, absorption, and fluorescence characteristics of water-soluble organic matter in atmospheric aerosols

Atmospheric Environment ◽

10.1016/j.atmosenv.2020.118159 ◽

2021 ◽

Vol 247 ◽

pp. 118159

Author(s):

Xingjun Fan ◽

Feng Cai ◽

Cuncun Xu ◽

Xufang Yu ◽

Yan Wang ◽

...

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Atmospheric Aerosols ◽

Water Soluble ◽

Soluble Organic Matter ◽

Fluorescence Characteristics

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Effect of syndiotacticity on the morphology of water-soluble low molecular weight poly(vinyl alcohol) by solution copolymerization of vinyl pivalate/vinyl acetate in tetrahydrofuran and saponification

Polymer ◽

10.1016/j.polymer.2004.03.077 ◽

2004 ◽

Vol 45 (12) ◽

pp. 4037-4043 ◽

Cited By ~ 8

Author(s):

Jeong Hyun Yeum ◽

Byung Chul Ji ◽

Seok Kyun Noh ◽

Han Yong Jeon ◽

Jin Woo Kwak ◽

...

Keyword(s):

Molecular Weight ◽

Vinyl Acetate ◽

Vinyl Alcohol ◽

Water Soluble ◽

Poly Vinyl Alcohol ◽

Low Molecular Weight

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Wound Healing Promotion by Hyaluronic Acid: Effect of Molecular Weight on Gene Expression and In Vivo Wound Closure

Pharmaceuticals ◽

10.3390/ph14040301 ◽

2021 ◽

Vol 14 (4) ◽

pp. 301

Author(s):

Yayoi Kawano ◽

Viorica Patrulea ◽

Emmanuelle Sublet ◽

Gerrit Borchard ◽

Takuya Iyoda ◽

...

Keyword(s):

Gene Expression ◽

Molecular Weight ◽

Wound Healing ◽

Hyaluronic Acid ◽

Healing Process ◽

Dermal Fibroblasts ◽

Water Soluble ◽

Wound Healing Process ◽

And Migration ◽

Proliferation And Migration

Hyaluronic acid (HA) has been known to play an important role in wound healing process. However, the effect of molecular weight (MW) of exogenously administered HA on the wound healing process has not been fully understood. In this study, we investigated HA with different MWs on wound healing process using human epidermal keratinocytes and dermal fibroblasts. Cell proliferation and migration ability were assessed by water soluble tetrazolium (WST) assay and wound scratch assay. We examined the effect of HA addition in a full-thickness wound model in mice and the gene expression related to wound healing. Proliferation and migration of HaCaT cells increased with the increase of MW and concentration of HA. Interleukin (IL-1β), IL-8 and vascular endothelial growth factor (VEGF) as well as matrix metalloproteinase (MMP)-9 and MMP-13 were significantly upregulated by high molecular weight (HMW) HA in keratinocytes. Together with VEGF upregulation and the observed promotion of HaCaT migration, HA with the MW of 2290 kDa may hold potential to improve re-epithelialization, a critical obstacle to heal chronic wounds.

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Effect of DMPA and Molecular Weight of Polyethylene Glycol on Water-Soluble Polyurethane

Polymers ◽

10.3390/polym11121915 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1915 ◽

Cited By ~ 2

Author(s):

Eyob Wondu ◽

Hyun Woo Oh ◽

Jooheon Kim

Keyword(s):

Molecular Weight ◽

Contact Angle ◽

Polyethylene Glycol ◽

Photoelectron Spectroscopy ◽

Water Solubility ◽

Soft Segment ◽

Water Soluble ◽

Size Exclusion ◽

Resonance Spectroscopy ◽

Scanning Calorimetry

In this study water-soluble polyurethane (WSPU) was synthesized from isophorone diisocyanate (IPDI), and polyethylene glycol (PEG), 2-bis(hydroxymethyl) propionic acid or dimethylolpropionic acid (DMPA), butane-1,4-diol (BD), and triethylamine (TEA) using an acetone process. The water solubility was investigated by solubilizing the polymer in water and measuring the contact angle and the results indicated that water solubility and contact angle tendency were increased as the molecular weight of the soft segment decreased, the amount of emulsifier was increased, and soft segment to hard segment ratio was lower. The contact angle of samples without emulsifier was greater than 87°, while that of with emulsifier was less than 67°, indicating a shift from highly hydrophobic to hydrophilic. The WSPU was also analyzed using Fourier transform infrared spectroscopy (FT-IR) to identify the absorption of functional groups and further checked by X-ray photoelectron spectroscopy (XPS). The molecular weight of WSPU was measured using size-exclusion chromatography (SEC). The structure of the WSPU was confirmed by nuclear magnetic resonance spectroscopy (NMR). The thermal properties of WSPU were analyzed using thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

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Characterization of water soluble pentosans of enzyme supplemented dough and breads/ Caracterización de las pentosanas solubles en agua extraídas de masa y pan conteniendo enzimas comerciales

Food Science and Technology International ◽

10.1177/108201320000600302 ◽

2000 ◽

Vol 6 (3) ◽

pp. 197-205 ◽

Cited By ~ 5

Author(s):

T. Jimenez ◽

M.A. Martinez-Anaya

Keyword(s):

Molecular Weight ◽

Ferulic Acid ◽

Synergistic Effects ◽

Extraction Yield ◽

Water Soluble ◽

Sugar Composition ◽

Enzyme Preparations ◽

Processing Enzyme ◽

Enzyme Source

Water soluble pentosans (WSP) from doughs and breads made with different enzyme preparations are characterized according to extraction yield, sugar composition, xylose/arabinose ratio and molecular weight (MW) distribution. Extraction yield was greater for dough than for bread samples, ranging from 0.94 to 1.64%, but bread extracts had a higher purity. Percent of pentoses in purified WSP was greater in pentosanase supplemented samples (28-55%) than in control and amylase containing samples (23-32%). Major sugars were xylose and arabinose, but glucose and mannose also appeared in the extracts. The xylose/arabinose (Xyl/Ara) ratio was 1.3-1.6 and underwent small changes during processing. Enzyme addition caused an increase in Xyl/Ara ratio, attributable to a debranching of arabinoxylans (AX) with higher degree of Ara substitution by arabinofuranosidase. Addition of pentosanases had a significant effect in increasing WSP with MW over 39 000, whereas those of low MW changed only slightly. MW distribution depended on enzyme source, and whereas some enzymes showed activity during fermentation others increased their activity during baking. No synergistic effects were observed in studied variables due to the combination of amylases with pentosanases. Protein in WSP extracts eluted together with ferulic acid suggesting they were linked, but not associated with a determined carbohydrate fraction.

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