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1.
Int J Biol Macromol ; 276(Pt 1): 133839, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004248

RESUMO

Functional compounds (FCs) had some functions, which are affected easily by digestion and transmembrane transport leading to low absorption rates, such as lutein, quercetin, xylo-oligosaccharide. Protein from blue foods is a potential bioactive compound, which had higher bioavailability, especially for bioactive peptides (BBPs). The BBPs has great limitations, especially the variability under pepsin digestion. However, the limitation of single FCs and BBPs in bioavailability might can be complemented by mixture of different bioactive compounds. Therefore, this review provides an in-depth study on the function and mechanism of different FCs/BBPs and their mixtures. Specifically, digestion effect of mixtures on function and transmembrane transport mechanisms of different bioactive compounds were exhibited to elaborate interactions between BBPs and FCs in delivery systems (function and bioavailability). Combination of FCs/BBPs could enhance bioactive compounds function by mutual complement of function mechanisms, as well as improving the function after digestion by regulating digestion process. Moreover, transmembrane absorption and transport of FCs/BBPs also could be facilitated by mixtures due to complement of transmembrane mechanism (endocytosis, protein channels, cell bypass way). This manuscript lays a foundation for the development of active ingredient bioavailability in functional food processing.

2.
Nanoscale Adv ; 6(6): 1643-1647, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38482033

RESUMO

The controlled conformational changes of planar graphene nanosheets are of great importance to the realization of their practical applications. Despite substantial effort in the area, the controlled folding of two-dimensional (2D) graphene sheets into one-dimensional (1D) structures still remains a significant challenge. Here, for the first time, we report an ice crystal guided folding strategy to fabricate 1D folded graphene nanobelts (FGBs), where the formation and growth of ice crystals in a confined space function to guide the folding of 2D graphene oxide (GO) nanosheets into 1D nanobelts (i.e. folded graphene oxide belts, FGOBs), which were subsequently converted to FGBs after annealing. Thin aqueous GO containing films were obtained by blowing air through a GO dispersion in the presence of a surfactant, polyoxypropylenediamine (D400), resulting in a foam containing uniform air bubbles. Subsequent shock cooling of the foam using liquid nitrogen resulted in the facile fabrication of FGOBs. This technique provides a general approach to encapsulate catalytic nanomaterials such as Fe3O4 nanorods, TiO2 and Co3O4 nanoparticles into the folded graphene structure for practical applications such as Li-ion batteries.

3.
Bioresour Technol ; 399: 130563, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461871

RESUMO

An ultralight 3D carbon fiber aerogel with good flexibility is developed via soaking cotton in water and then calcinating at a high temperature. This cotton-derived carbon material is constituted by amorphous carbon and retains slight oxygen-containing groups. Besides, a lot of hollow carbon nanocapsules are yielded on the inside surface, resulting in abundant micropores and mesopores. Systemic investigations explore the molecular transformation from cotton to carbon fiber, and the formation of carbon nanocapsules. In the adsorption process for methyl orange (MO), this carbon fiber aerogel exhibits both a rapid adsorption rate and the ultrahigh adsorbability of 862.9 mg/g, outclassing most of carbon materials reported. Therefore, a dynamic sewage treatment system is built and consecutively removes hydrosoluble pollution for a long-term running time. For the cotton-derived carbon fiber aerogel, the good mechanical flexibility, excellent adsorption property, and high stability jointly provide a vast application prospect in future industrial wastewater remediation.


Assuntos
Nanocápsulas , Poluentes Químicos da Água , Fibra de Carbono , Carbono , Esgotos , Adsorção , Gossypium
4.
Chemosphere ; 310: 136819, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36241117

RESUMO

While it has been recognized that sulfidation can effectively improve the reactivity of microscale zero valent iron (mZVI), there is limited understanding of nitrobenzene (ArNO2) removal by sulfidated mZVI. To understand the reduction capacity and pathway of ArNO2 by sulfidated mZVI, ball-milling sulfidated mZVI (S-mZVIbm) with different S/Fe molar ratios (0-0.2) was used to conduct this experiment. The results showed that sulfidation could efficiently enhance ArNO2 removal under iron-limited and iron excess conditions, which was attributed to the presence of FeSx sites that could provide higher Fe(0) utilization efficiency and stronger passivation resisting for S-mZVIbm. The optimum ArNO2 reduction could be obtained by S-mZVIbm with S/Fe molar ratio at 0.1, which could completely transform ArNO2 to aniline (ArNH2) with a rate constant of 4.36 × 10-2 min-1 during 120-min reaction. FeSx phase could act as electron transfer sites for ArNO2 reduction and it could still be reserved in S-mZVIbm after reduction reaction. The product distribution indicated that sulfidation did not change the types of reduction products, while the removal of ArNO2 by S-mZVIbm was a step-by-step reduction progress along with the adsorption of ArNH2. In addition, a faster reduction of ArNO2 in groundwater/soil system further demonstrated the feasibility of S-mZVIbm in the real field remediation.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Ferro , Poluentes Químicos da Água/análise , Nitrobenzenos
5.
J Hazard Mater ; 423(Pt A): 127020, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34481402

RESUMO

In this study an electromagnetic heating strategy is proposed for remediation of trichloroethene (TCE) by ball milled, sulfidated microscale zero valent iron (S-mZVIbm) particles. S-mZVIbm is ferromagnetic, which generates heat under the application of a low-frequency alternating current electromagnetic field (AC EMF). We found that the temperature reached up to ~120 â„ƒ during 30-min electromagnetic induction heating of 10 g/L S-mZVIbm (with S/Fe molar ratio of 0.1), compared with ~55 â„ƒ and ~80 â„ƒ for ZVI and ball milled mZVIbm, respectively. The application of AC EMF accelerated the TCE degradation rate (kTCE = 5.5 × 10-1 h-1) by up to 4-fold without compromising or even enhancing electron efficiency of S-mZVIbm compared to no-heating. Furthermore, this process halved the generation of chlorinated intermediate, cis-DCE. In contrast, water-bath heating only increased the dechlorination rate 2-fold with unchanged cis-DCE generation and lowered electron efficiency. This is attributed to both rising temperature by induction heating and accelerated ZVI corrosion and surface Fe0 exposure caused by AC EMF. In real groundwater, the AC EMF maintained the same promoting effects for TCE dechlorination by S-mZVIbm. This study shows that combination of filed-scale available AC EMF with S-mZVIbm provides a promising approach for remediation of chlorinated hydrocarbons in contaminated groundwater.

6.
Nanotechnology ; 31(37): 375604, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32454467

RESUMO

Using citric acid (CA) and 1,5-naphthalenedisulfonic acid (NDSA) as the structure-directing agent, a hierarchical flower-like Bi2O2CO3 product is successfully prepared via a simple one-step hydrothermal synthesis, which is spirally assembled by the {001} facet-dominated nanosheets. It is testified that the additive CA plays an important inducing role in forming the chemical composition of Bi2O2CO3, the nanosized sheet-type subunits, and the exposure of the {001} facet, while the NDSA greatly improves the dispersity and porous structure of the Bi2O2CO3 microflower. Due to the nano-size effect and distortion of surface Bi-O bonds, the Bi2O2CO3 microflower could be excited by the visible light to exhibit a superior photocatalytic performance in the degradation of tetracycline (TC). Besides, it is found the exposed {001} facet of Bi2O2CO3 would preferentially generate holes during the illumination process, thus enhancing the photooxidative activity of the Bi2O2CO3 microflower. Finally, the structural and optical features of the Bi2O2CO3 microflower have been discussed in detail, and its photocatalytic mechanism has also been proposed in this work.

7.
ACS Omega ; 2(9): 6104-6111, 2017 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30023763

RESUMO

A novel metal foam-based Fenton-like process for wastewater treatment is illustrated in this study. In the system, H2O2 was generated in situ by taking advantage of O2 in air, as metal could activate dissolved O2 to produce •O2- and then generate H2O2. Furthermore, metal foam can enhance the Fe3+/Fe2+ cycling, which eventually improved the efficiency of the Fenton process. The performance of the novel Fenton-like process was assessed by methyl blue (MB), and 94% MB removal could be achieved within 5 min in nickel (Ni) foam system. The degradation of MB in this study was based on both •OH and •O2- radicals, where •O2- radical served as the precursor to generate •OH for MB degradation through a Fenton process. The pH value of 3 with the initial Fe2+ concentration of 0.25 mM was found to be the optimum condition for the Fenton-like process. This study provides a general and new strategy for efficient wastewater treatment just using aeration and metal foams (such as Ni, Al, and Cu foams), which also offers a good alternative for rational design and application of traditional Fenton process.

8.
J Hazard Mater ; 314: 32-40, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27107233

RESUMO

To overcome the limits of graphene oxide (GO) as a novel sorbent for heavy metal removal (e.g., low sorption selectivity and difficulty in solid-liquid separation), a nanocomposite (HMO@GO) with excellent settling ability (<2min) was fabricated through in situ growing nanosized hydrated manganese oxide (HMO) (10.8±4.1nm) on GO. As a graphene-based adsorbent, HMO@GO exhibited fast sorption kinetics (<20min). Meanwhile, the introduced HMO endowed HMO@GO with outstanding sorption selectivity and capacity toward Pb(II) (>500mgg(-1)) in the presence of high-level competing Ca(II). Cyclic sorption batches showed that 1kg HMO@GO can treat at least 22m(3) Pb(II)-laden synthetic industrial drainage (5mgL(-1) Pb(II)) and 40m(3) drinking water (0.5mgL(-1) Pb(II)) to their corresponding limits (0.1mgL(-1) for wastewater and 10µgL(-1) for drinking water) enforced in China. Additionally, the exhausted HMO@GO can be effectively regenerated using 0.3 M HCl for repeated uses. The eminent performance of HMO@GO was attributed to its specific structure, that is, the abundant oxygen-containing groups on GO mediated the growth of highly dispersed HMO that preferably sequestrated Pb(II) through specific interaction, and the host GO offered the preconcentration of Pb(II) for enhanced sequestration through the Donnan membrane effect.

9.
Nanoscale ; 8(4): 2159-67, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26730571

RESUMO

Nitrogen-doped graphene nanoribbon aerogels (N-GNRAs) are fabricated through the self-assembly of graphene oxide nanoribbons (GONRs) combined with a thermal annealing process. Amino-groups are grafted to the surface of graphene nanoribbons (GNRs) by an epoxy ring-opening reaction. High nitrogen doping level (7.6 atm% as confirmed by elemental analysis) is achieved during thermal treatment resulting from functionalization and the rich edge structures of GNRs. The three dimensional (3D) N-GNRAs feature a hierarchical porous structure. The quasi-one dimensional (1D) GNRs act as the building blocks for the construction of fishnet-like GNR sheets, which further create 3D frameworks with micrometer-scale pores. The edge effect of GNRs combined with nitrogen doping and porosity give rise to good electrical conductivity, superhydrophilic, highly compressible and low density GNRAs. As a result, a high capacity of 910 mA h g(-1) is achieved at a current density of 0.5 A g(-1) when they are tested as anode materials for lithium ion batteries. Further cell culture experiments with the GNRAs as human medulloblastoma DAOY cell scaffolds demonstrate their good biocompatibility, inferring potential applications in the biomedical field.


Assuntos
Técnicas de Cultura de Células/métodos , Grafite/química , Lítio/química , Nanotubos de Carbono/química , Nitrogênio/química , Linhagem Celular Tumoral , Géis , Humanos
10.
PLoS One ; 10(10): e0138672, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26444687

RESUMO

A three-dimensional modelling approach is used to study the effects of operating and ambient conditions on the thermal behaviour of the spiral wound supercapacitor. The transient temperature distribution during cycling is obtained by using the finite element method with an implicit predictor-multicorrector algorithm. At the constant current of 2A, the results show that the maximum temperature appears in core area. After 5 cycles, the maximum temperature is 34.5°C, while in steady state, it's up to 42.5°C. This paper further studies the relationship between the maximum temperature and charge-discharge current. The maximum temperature will be more than 60°C after 5 cycles at the current of 4A, and cooling measurements should be taken at that time. It can provide thoughts on inner temperature field distribution and structure design of the spiral wound supercapacitor in working process.


Assuntos
Eletricidade , Análise de Elementos Finitos , Temperatura , Condutividade Térmica , Algoritmos
11.
ACS Appl Mater Interfaces ; 6(5): 3242-9, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24524309

RESUMO

The idea of extending functions of graphene aerogels and achieving specific applications has aroused wide attention recently. A solution to this challenge is the formation of a hybrid structure where the graphene aerogels are decorated with other functional nanostructures. An infiltration-evaporation-curing strategy has been proposed by the formation of hybrid structure containing poly(dimethylsiloxane) (PDMS) and compressible graphene aerogel (CGA), where the cellular walls of the CGA are coated uniformly with an integrated polymer layer. The resulting composite shows enhanced compressive strength and a stable Young's modulus that are superior to those of pure CGAs. This unique structure combines the advantages of both components, giving rise to an excellent electromechanical performance, where the bulk resistance repeatedly shows a synchronous and linear response to variation of the volume during compression at a wide range of compressed rates. Furthermore, the foamlike structure delivers a water droplet with "sticky" superhydrophobicity and a size as large as 32 µL that remains tightly pinned to the composite, even when it is turned upside-down. This is the first demonstration of superhydrophobicity with strong adhesion on a foamlike structure. These outstanding properties qualify the PDMS/CGA composites developed here as promising candidates for a wide range of applications such as in sensors, actuators, and materials used for biochemical separation and tissue engineering.

12.
Adv Mater ; 25(15): 2219-23, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23418081

RESUMO

Chemically converted graphene aerogels with ultralight density and high compressibility are prepared by diamine-mediated functionalization and assembly, followed by microwave irradiation. The resulting graphene aerogels with density as low as 3 mg cm(-3) show excellent resilience and can completely recover after more than 90% compression. The ultralight graphene aerogels possessing high elasticity are promising as compliant and energy-absorbing materials.


Assuntos
Géis/química , Grafite/química , Adsorção , Diaminas/química , Elasticidade , Micro-Ondas , Nanotecnologia
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