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1.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257376

RESUMO

The long-term presence of PPCPs in the aqueous environment poses a potentially significant threat to human life and physical health and the safety of the water environment. In our previous work, we investigated low-cost pitch-based HCP adsorbents with an excellent adsorption capacity and magnetic responsiveness through a simple one-step Friedel-Crafts reaction. In this work, we further investigated the adsorption behavior of the prepared pitch-based adsorbents onto three PPCP molecules (DFS, AMP, and antipyrine) in detail. The maximum adsorption capacity of P-MPHCP for DFS was 444.93 mg g-1. The adsorption equilibrium and kinetic processes were well described through the Langmuir model and the proposed secondary kinetic model. The negative changes in Gibbs free energy and enthalpy reflected that the adsorption of HCPs onto PPCPs was a spontaneous exothermic process. The recoverability results showed that the adsorption of MPHCP and P-MPHCP onto DFS remained above 95% after 10 adsorption-desorption cycles. The present work further demonstrates that these pitch-based adsorbents can be used for multiple applications, which have a very extensive practical application prospect.

2.
J Environ Manage ; 339: 117763, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031597

RESUMO

Silver is an important precious metal with superior ductility, electrical and thermal conductivity, photosensitivity, and antibacterial properties. However, without proper recycling and treatment, silver emissions may pose a threat to the human health and subsistence environment due to their toxicity. Therefore, it is environmentally and economically important to recover Ag from waste electronic equipment and anode slime. Herein, carboxyl functionalized modified magnetic nanoparticles (Fe3O4@3-phenylglutaricacid nanoparticles) were designed and prepared to obtain the low-cost magnetic pitch-based HCP adsorbents (MPHCP and P-MPHCP). The novelty of present work is that superior adsorption capacity and magnetic responsiveness of adsorbent can be obtained by a simple one-step Friedel-Crafts reaction with very low-cost raw material. The maximum Ag+ adsorption capacity of MPHCP and P-MPHCP were 321 and 353 mg/g, respectively. The adsorption was completed within a short duration of 15 min for MPHCP and P-MPHCP at an initial Ag+ concentration of 100 mg/L. Moreover, the most selective is P-MPHCP wherein Ag+ is α = 61 times more selective than Pb2+ at a concentration of 100 mg/L.The adsorption capacity of MPHCP and P-MPHCP towards Ag+ still maintains above 89% after ten cycles of adsorption-desorption. This study not only provides new guidance for the development of porous polymeric adsorbents but also provides technical feasibility for the field of recovery and reutilization of precious metals, which has a very extensive practical application prospect.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Humanos , Prata , Polímeros , Adsorção , Fenômenos Magnéticos , Poluentes Químicos da Água/análise
3.
ACS Appl Mater Interfaces ; 14(31): 35745-35754, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35914116

RESUMO

The built-in electric field (BEF) has been considered as the key kinetic factor for facilitating efficient photoinduced carrier separation and migration of polymeric photocatalysts. Enhancing the BEF of the polymers could enable a directional migration of the photogenerated carriers to accelerate photogenerated charge separation and thus boost photocatalytic performances. However, achieving this approach remains a formidable challenge, which has never been realized in conjugated microporous polymers (CMPs). Herein, we developed a molecular dipole control strategy to modulate the BEF in CMPs by varying the nature of the core. As a result, a series of CMPs with a tunable BEF were designed and prepared via FeCl3-mediated coupling of bicarbazole with different acceptor cores. The optimized CbzCMP-9 featured the strongest BEF induced by its high molecular dipole, which grants it with a powerful driving force to accelerate exciton dissociation into electron-hole pairs and facilitates charge transfer along the backbone of CMPs to the surface, resulting in a remarkable photocatalytic performance toward thiocyano chromones and C-3 thiocyanation of indoles (up to 95 and 98% yields, respectively) and prominently surpassing many other reported photocatalysts. In brief, the proposed strategy highlights that enhancing the BEF by modulating molecular dipole can lead to a dramatic improvement in photocatalytic performance, which is expected to be employed for constructing other photocatalytic systems with high performance.

4.
PLoS One ; 17(3): e0265097, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35259197

RESUMO

The influence of compaction methods such as the Marshall compaction method (MCM), vibration compaction method (VCM) and gyration compaction method (GCM), on the performance of stone mastic asphalt (SMA-13) mixture has yet to be explored. Therefore, to compare the influences of compaction methods and work on the physical and mechanical properties of SMA-13 mixture, the volume parameters, mechanical properties, and gradation changes of SMA-13 mixture specimens prepared under different vibration compaction times, Marshall double-compaction numbers, and gyration compaction numbers were studied. The compaction method for SMA-13 mixture design was also proposed under the principle of optimum properties. Results demonstrate that the asphalt aggregate ratio and compaction work directly affect the volumetric properties (VV, VFA, and VMA) of asphalt mixture specimens while the raw material and mineral aggregate gradation were fixed. The influence of compaction work on physical properties is greater than that of asphalt aggregate ratio. The mechanical strength of VCM and GCM specimens is higher than that of MCM specimens under the same compaction work and the optimum asphalt aggregate ratio. With the increase in compaction work, the mechanical properties of SMA-13 mixture are improved at the same compaction method and the optimum asphalt aggregate ratio. The aggregate gradation of the SMA-13 mixture before and after compacted using VCM and GCM changes minimally compared with that of the SMA-13 mixture compacted by MCM. Thus, the compaction methods of VCM65 and GCM130 were recommended for SMA-13 mixture design.


Assuntos
Minerais
5.
J Colloid Interface Sci ; 584: 866-874, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33097225

RESUMO

Poly(ionic liquid) membranes (PILMs) can be potentially applied as polyelectrolyte materials in the separation of ampholytes such as amino acids. Therefore, poly(amino acid ionic liquid) membranes (PAAILMs) were prepared by blending poly(amino acid ionic liquids) (PAAILs) and polyvinylidene fluoride (PVDF) in this study. These PAAILMs were characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA). Moreover, their mechanical properties, antibacterial and antifouling properties were evaluated. The zeta potential, pore size distribution, porosity, and specific surface area of these membranes were also measured. The membranes were used to separate the amino acid mixture of l-phenylalanine and l-aspartic acid, which are essential for the synthesis of aspartame. The PAAILMs can be used for the selective separation of l-phenylalanine and l-aspartic acid through the Donnan effect. A maximum selectivity of 65% was obtained for the mixed amino acids via one-step separation. These PAAILMs have the advantages of low operating pressure, high water flux, good antibacterial and antifouling properties, and excellent reusability, thereby indicating their potential for industrial application in the separation of l-phenylalanine and l-aspartic acid.


Assuntos
Líquidos Iônicos , Aminoácidos , Antibacterianos/farmacologia , Membranas Artificiais , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Macromol Rapid Commun ; 41(7): e2000006, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32096912

RESUMO

The development of new photocatalytic platforms using novel semiconductor material is an important challenge. Herein, a sp2 carbon-conjugated covalent triazine polymer (sp2 c-CTP-4), featuring a vinylene bridge and extended π-conjugation, is prepared as a highly efficient photocatalyst for degradation of methylene blue. sp2 c-CTP-4 exhibits substantial semiconducting properties such as enhanced charge transfer and prolonged lifetime of carriers compared to its counterparts with CN or CC connections, likely due to its extended π-delocalization with an unencumbered CC bridge. Moreover, benefiting from its high chemical stability, the as-made catalyst can be recycled five times with good retention of photocatalytic activity. This study provides a new pathway for constructing a robust platform for efficient photocatalysis and gives insight into the structure-property relationship of conjugated polymers.


Assuntos
Luz , Azul de Metileno/química , Polímeros/química , Triazinas/química , Catálise , Estrutura Molecular , Tamanho da Partícula , Processos Fotoquímicos , Compostos de Vinila/química
7.
ACS Appl Mater Interfaces ; 11(30): 27335-27342, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31328498

RESUMO

Three kinds of carbazole-based porous organic polymers were successfully prepared via simple Friedel-Crafts alkylation of 1,3,5-tri(9-carbazolyl)-benzene. External cross-linking agents named 1,4-bis(chloromethyl)-benzene, cyanuric chloride, and 1,4-dimethoxybenzene were selected, and the derived polymers (denoted as CSU-CPOPs-1, CSU-CPOPs-2, and CSU-CPOPs-3) gave high surface areas (up to 1032 m2/g) and good stability. Interestingly, varying the nature of "knitting" agents led to an unprecedented morphology evolution, and it is worth noting that a mulberry-like morphology was observed for the case of 1,4-bis(chloromethyl)-benzene. Taking advantage of the unique mulberry-like morphology as well as abundant porosity, CSU-CPOPs-1 showed ultrahigh iodine vapor adsorption performance with a capacity of 494 wt % at 348 K and 1 bar, which is the highest value reported to date for amorphous polymers. This study presented a feasible way to develop efficient iodine sorbents with tunable morphologies for addressing environmental issues.

8.
Chem Commun (Camb) ; 54(61): 8450-8453, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-29963659

RESUMO

Rich heteroatom-doped conjugated nanoporous polymers with uniform microspherical morphology exhibit remarkably high capacity up to 450 wt% for removing iodine from the vapor phase (at 348 K and atmospheric pressure).

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 6): m806-7, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21202492

RESUMO

In the title heteronuclear Ni(II)-Ho(III) complex (systematic name: {µ-6,6'-dieth-oxy-2,2'-[ethane-1,2-diylbis(nitrilo-methyl-idyne)]diphenolato-1κ(4)O(1),O(1'),O(6),O(6'):2κ(4)O(1),N,N',O(1')}trinitrato-1κ(6)O,O'-holmium(III)nickel(II)), [HoNi(C(20)H(22)N(2)O(4))(NO(3))(3)], with the hexa-dentate Schiff base compartmental ligand N,N'-bis-(3-ethoxy-salicyl-idene)ethyl-enediamine (H(2)L), the Ho and Ni atoms are doubly bridged by two phenolate O atoms of the Schiff base ligand. The coordination of Ni is square-planar with the donor centers of two imine N atoms and two phenolate O atoms. The holmium(III) center has a tenfold -coordination environment of O atoms, involving the phenolate O atoms, two eth-oxy O atoms and two O atoms each from the three nitrates. Weak C-H⋯O and O⋯Ni [3.383 (4) Å] inter-actions generate a two-dimensional zigzag sheet.

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