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1.
Environ Sci Pollut Res Int ; 31(20): 29264-29279, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38573576

RESUMO

Guided by efficient utilization of natural plant oil and sulfur as low-cost sorbents, it is desired to tailor the porosity and composition of polysulfides to achieve their optimal applications in the management of aquatic heavy metal pollution. In this study, polysulfides derived from soybean oil and sulfur (PSSs) with improved porosity (10.2-22.9 m2/g) and surface oxygen content (3.1-7.0 wt.%) were prepared with respect to reaction time of 60 min, reaction temperature of 170 °C, and mass ratios of sulfur/soybean oil/NaCl/sodium citrate of 1:1:3:2. The sorption behaviors of PSSs under various hydrochemical conditions such as contact time, pH, ionic strength, coexisting cations and anions, temperature were systematically investigated. PSSs presented a fast sorption kinetic (5.0 h) and obviously improved maximum sorption capacities for Pb(II) (180.5 mg/g), Cu(II) (49.4 mg/g), and Cr(III) (37.0 mg/g) at pH 5.0 and T 298 K, in comparison with polymers made without NaCl/sodium citrate. This study provided a valuable reference for the facile preparation of functional polysulfides as well as a meaningful option for the removal of aquatic heavy metals.


Assuntos
Cobre , Chumbo , Metais Pesados , Óleo de Soja , Sulfetos , Poluentes Químicos da Água , Adsorção , Chumbo/química , Óleo de Soja/química , Cobre/química , Sulfetos/química , Porosidade , Poluentes Químicos da Água/química , Metais Pesados/química , Cromo/química , Cinética , Concentração de Íons de Hidrogênio
2.
Environ Sci Pollut Res Int ; 31(11): 16940-16957, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38326685

RESUMO

The applications of polysulfides derived from natural plant oil and sulfur via the inverse vulcanization in the removal of heavy metals from aqueous solutions suffered from their low porosity and scarce surface functionality because of their hydrophobic surfaces and bulk characteristics. In this study, polysulfides from sulfur and palm oil (PSPs) with significantly enhanced porosity (13.7-24.1 m2/g) and surface oxygen-containing functional groups (6.9-8.6 wt.%) were synthesized with the optimization of process conditions including reaction time, temperature, and mass ratios of sulfur/palm oil/NaCl/sodium citrate. PSPs were applied as sorbents to remove heavy metals present in aqueous solutions. The integration of porosity and oxygen modification allowed a fast kinetic (4.0 h) and enhanced maximum sorption capacities for Pb(II) (218.5 mg/g), Cu(II) (74.8 mg/g), and Cr(III) (68.4 mg/g) at pH 5.0 and T 298 K comparing with polysulfides made without NaCl/sodium citrate. The sorption behaviors of Pb(II), Cu(II), and Cr(III) on PSPs were highly dependent on the solution pH values and ionic strength. The sorption presented excellent anti-interference capability for the coexisting cations and anions. The sorption processes were endothermic and spontaneous. This work would guide the preparation of porous polysulfides with surface modification as efficient sorbents to remediate heavy metals from aqueous solutions.


Assuntos
Metais Pesados , Sulfetos , Poluentes Químicos da Água , Porosidade , Cloreto de Sódio , Chumbo , Óleo de Palmeira , Citrato de Sódio , Metais Pesados/química , Água , Enxofre , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/química
3.
PLoS One ; 18(11): e0294467, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38015903

RESUMO

This study empirically examines the interplay between market integration and economic growth across nine cities within the Pearl River Delta urban agglomeration. The findings indicate that the city cluster's market integration negatively impacts regional economic development and has a negligible effect on the surrounding areas. In response, the research recommends the elimination of market trade barriers and a reduction in local protectionism within the city cluster. Additionally, infrastructure enhancement is essential to leverage the distinct comparative advantages of each city within the Pearl River Delta urban agglomeration. An efficient collaboration mechanism is crucial to amplify the collective economic potency of the region.


Assuntos
Desenvolvimento Econômico , Rios , Cidades , China
4.
Front Psychol ; 12: 799164, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35401290

RESUMO

This study introduces the self-construction methods of consumers and the tendency characteristics of experiential purchase to study the effects of physical purchase and experiential purchase on wellbeing. The dependent self-builders obtain higher happiness from experiential purchase; however, the independent self-builders get higher happiness from physical purchase. Furthermore, consumers with a high purchase experience get higher happiness from experiential purchase. Consumers with high material consumption tendency get significantly higher happiness than physical purchase from experiential purchase. Consumers with high materialism tendency gain higher happiness in experiential purchase, which is in line with the expectations of self-construction and consumption theories. This study provides the first evidence for the impact of self-construction methods on wellbeing with different consumption choices.

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