scholarly journals Chromogenic Chemodosimeter Based on Capped Silica Particles to Detect Spermine and Spermidine

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 818
Author(s):  
Mariana Barros ◽  
Alejandro López-Carrasco ◽  
Pedro Amorós ◽  
Salvador Gil ◽  
Pablo Gaviña ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Organic Matter ◽  
Porous Material ◽  
Inorganic Material ◽  
Rhodamine 6G ◽  
Hydrophobic Interactions ◽  
Silica Particles ◽  
External Layer ◽  
Fluorimetric Titration ◽  
Mcm 41

A new hybrid organic–inorganic material for sensing spermine (Spm) and spermidine (Spd) has been prepared and characterized. The material is based on MCM-41 particles functionalized with an N-hydroxysuccinimide derivative and loaded with Rhodamine 6G. The cargo is kept inside the porous material due to the formation of a double layer of organic matter. The inner layer is covalently bound to the silica particles, while the external layer is formed through hydrogen and hydrophobic interactions. The limits of detection determined by fluorimetric titration are 27 µM and 45 µM for Spm and Spd, respectively. The sensor remains silent in the presence of other biologically important amines and is able to detect Spm and Spd in both aqueous solution and cells.

scholarly journals Synthesis of 13C-enriched amino acids with 13C-depleted insoluble organic matter in a formose-type reaction in the early solar system

2021 ◽  
Vol 7 (18) ◽  
pp. eabd3575
Author(s):  
Yoshihiro Furukawa ◽  
Yoshinari Iwasa ◽  
Yoshito Chikaraishi
Keyword(s):  
Aqueous Solution ◽  
Organic Matter ◽  
Solar System ◽  
Acid Synthesis ◽  
Soluble Organic Matter ◽  
Early Solar System ◽  
Cold Region ◽  
Amino Acid Synthesis ◽  
Type Reaction ◽  
Insoluble Organic Matter

Solvent-soluble organic matter (SOM) in meteorites, which includes life’s building molecules, is suspected to originate from the cold region of the early solar system, on the basis of 13C enrichment in the molecules. Here, we demonstrate that the isotopic characteristics are reproducible in amino acid synthesis associated with a formose-type reaction in a heated aqueous solution. Both thermochemically driven formose-type reaction and photochemically driven formose-type reaction likely occurred in asteroids and ice-dust grains in the early solar system. Thus, the present results suggest that the formation of 13C-enriched SOM was not specific to the cold outer protosolar disk or the molecular cloud but occurred more widely in the early solar system.

Simultaneous oxidation and reduction treatments of polluted water by a bio-electro reactor

1996 ◽  
Vol 34 (9) ◽  
pp. 101-108 ◽  
Author(s):  
M. Kuroda ◽  
T. Watanabe ◽  
Y. Umedu
Keyword(s):  
Aqueous Solution ◽  
Organic Matter ◽  
Electric Current ◽  
Removal Efficiency ◽  
Concentration Ratio ◽  
Nitrate Removal ◽  
Hydrogen Gas ◽  
Polluted Water ◽  
Simultaneous Oxidation ◽  
Denitrifying Microorganisms

Application of a bio-electro reactor for treatment of various kinds of polluted water was investigated experimentally. Aqueous solution of nitrate, ammonium and/or organic matter were used as synthetic polluted water. Denitrification of the nitrate polluted water without organic matter proceeded effectively by utilizing hydrogen gas produced by electrolysis of water in the reactor. The bio-electro reactor was also available for the treatment of nitrate polluted water containing organic matter when the C/N concentration ratio was up to 1.0 under the condition of 100 mA of applied electric current. The nitrate removal efficiency from nitrate polluted water containing acetate at C/N=1.0 was more than 90% at 5 hours of HRT and 80% even at 2.8 h HRT. For the treatment of ammonium polluted water, nitrification and denitrification proceeded simultaneously in a bio-electro reactor where nitrifying and denitrifying microorganisms were immobilized on the electrodes. The results obtained in this study suggested that the bio-electro reactor system was capable to application for oxidation and reduction treatments of the nitrate and ammonium polluted water.

Rapid removal of caffeine in aqueous solutions by peroxymonosulfate oxidant activated with cobalt ion

2015 ◽  
Vol 72 (3) ◽  
pp. 478-483 ◽  
Author(s):  
Yunleiyu Guo ◽  
Tingting Shen ◽  
Chen Wang ◽  
Jing Sun ◽  
Xikui Wang
Keyword(s):  
Aqueous Solution ◽  
Organic Matter ◽  
Aqueous Solutions ◽  
Ph Value ◽  
Neutral Condition ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Negative Effects ◽  
Cobalt Ion ◽  
Rapid Removal

The removal of caffeine (CAF) in aqueous solution by peroxymonosulfate oxidant activated with cobalt ion was investigated under a variety of operating conditions. The effects of various operating parameters, such as oxone and Co2+ concentrations, pH value, and the coexistence of dissolved organic matter and inorganic anions on the removal of CAF have been investigated. The removal efficiency increased with the increase in the concentrations of oxone and Co2+ ion added. The additions of chloride, bicarbonate, and sodium humate have negative effects on the removal of CAF. Near-neutral condition (5.0 < pH < 7.0) is favorable for the removal of CAF. Based on our experiments, 100% degradation of 50 mg/L CAF can be achieved within 4 minutes under the conditions of 1.00 mM oxone and 0.10 mM Co2+ ion at pH 5.0–7.0.

Sorption of hydrophobic pesticides to aliphatic components of soil organic matter

2003 ◽  
Author(s):  
Benny Chefetz ◽  
Baoshan Xing
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Organic Pollutants ◽  
Agricultural Soils ◽  
Hydrophobic Interactions ◽  
Spectroscopic Techniques ◽  
Plant Materials ◽  
Hydrophobic Compounds ◽  
High Sorption ◽  
Sorption Mechanisms

Sorption of hydrophobic compounds to aliphatic components of soil organic matter (SOM) is poorly understood even though these aliphatic carbons are a major fraction of SOM. The main source of aliphatic compounds in SOM is above- and below-ground plant cuticular materials (cutin, cutan and suberin). As decomposition proceeds, these aliphatic moieties tend to accumulate in soils. Therefore, if we consider that cuticular material contributes significantly to SOM, we can hypothesize that the cuticular materials play an important role in the sorption processes of hydrophobic compounds (including pesticides) in soils, which has not yet been studied. The overall goal of this research was to illustrate the mechanism and significance of the refractory aliphatic structures of SOM in sorbing hydrophobic compounds (nonionic and weakly polar pesticides). The importance of this study is related to our ability to demonstrate the sorption relationship between key pesticides and an important fraction of SOM. The specific objectives of the project were: (1) To isolate and characterize cuticular fractions from selected plants; (2) To investigate the sorption mechanism of key hydrophobic pesticides and model compounds to cuticular plant materials; (3) To examine the sorption mechanisms at the molecular level using spectroscopic techniques; (4) To investigate the sorption of key hydrophobic pesticides to synthetic polymers; (5) To evaluate the content of cuticular materials in agricultural soils; and (6) To study the effect of incubation of plant cuticular materials in soils on their sorptive capabilities. This project demonstrates the markedly high sorption capacity of various plant cuticular fractions for hydrophobic organic compounds (HOCs) and polar organic pollutants. Both cutin (the main polymer of the cuticle) and cutan biopolymers exhibit high sorption capability even though both sorbents are highly aliphatic in nature. Sorption by plant cuticular matter occurs via hydrophobic interactions and H-bonding interactions with polar sorbates. The cutin biopolymer seems to facilitate reversible and noncompetitive sorption, probably due to its rubbery nature. On the other hand, the epicuticular waxes facilitate enhance desorption in a bi-solute system. These processes are possibly related to phase transition (melting) of the waxes that occur in the presence of high solute loading. Moreover, our data highlight the significance of polarity and accessibility of organic matter in the uptake of nonpolar and polar organic pollutants by regulating the compatibility of sorbate to sorbent. In summary, our data collected in the BARD project suggest that both cutin and cutan play important roles in the sorption of HOCs in soils; however, with decomposition the more condensed structure of the cutin and mainly the cutan biopolymer dominated sorption to the cuticle residues. Since cutin and cutan have been identified as part of SOM and humic substances, it is suggested that retention of HOCs in soils is also controlled by these aliphatic domains and not only by the aromaticrich fractions of SOM.

High Stable Al-MCM-41: Structural Characterization and Evaluation for Removal of Methylene Blue from Aqueous Solution

Silicon ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 2017-2029 ◽  
Author(s):  
Wafaa E. Rashwan ◽  
Khaled S. Abou-El-Sherbini ◽  
Mohammed A. Wahba ◽  
Sohair A. Sayed Ahmed ◽  
Peter G. Weidler
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Structural Characterization ◽  
Mcm 41

scholarly journals Removal of trivalent metal ions from aqueous solution via cross-flow ultrafiltration system using zeolite membranes

2016 ◽  
Vol 7 (1) ◽  
pp. 66-76 ◽  
Author(s):  
Ashim Kumar Basumatary ◽  
R. Vinoth Kumar ◽  
Kannan Pakshirajan ◽  
G. Pugazhenthi
Keyword(s):  
Aqueous Solution ◽  
Contact Angle ◽  
Metal Ions ◽  
Cross Flow ◽  
Zeolite Membrane ◽  
Trivalent Metal ◽  
Zeolite Membranes ◽  
Ceramic Support ◽  
Trivalent Metal Ions ◽  
Mcm 41

This study aimed to assess the performance of three zeolite membranes in the removal of trivalent metal ions from aqueous solution using a cross-flow mode of operation. Three types of zeolite membrane, MCM-41, MCM-48 and FAU, were prepared on a low-cost, circular ceramic support by hydrothermal treatment. The three zeolite membranes were characterized by using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and contact angle measurements. The XRD results confirmed the formation of zeolites. The deposition of zeolite on the ceramic support and hydrophilicity of zeolite membranes were monitored by FESEM and contact angle measurement, respectively. The pore size of the MCM-41, MCM-48 and FAU membrane was found to be 0.173 μm, 0.142 μm, and 0.153 μm, respectively, which was lower than that of the support (1.0 μm). The fabricated zeolite membranes were used to investigate the separation behavior of trivalent metal ions (Al3+ and Fe3+) from aqueous solution at various applied pressures. It was observed that an increase of applied pressure leads to a slight decrease in the removal efficiency. Among the various zeolite membranes, the FAU membrane showed the maximum rejection of 88% and 83% for Fe3+ and Al3+ separation, respectively.

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