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1.
Front Chem ; 11: 1162909, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37188094

RESUMO

Biochar materials have attracted people's attention because of their environmental friendliness, abundant resources, and the use of waste resources for reuse. As a potassium-ion anode material, biomass char materials synthesized by different methods have broad application prospects. However, due to the problems of low initial magnification and limited potassium-storage capacity, it is necessary to improve the electrochemical performance through modifications, such as atomic doping. Atomic doping is an effective way to improve battery conductivity and potassium storage. In this paper, the synthesis method of biochar as an anode material for potassium-ion batteries and the influence of atomic doping on its modification in recent years are reviewed.

2.
Cancers (Basel) ; 14(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35884547

RESUMO

Dihydromyricetin (DHM) is a natural flavonoid compound extracted from Ampelopsis grossedentata that has been used for centuries in traditional Chinese medicine. DHM has attracted intensive attention due to its numerous beneficial activities, such as hepatoprotection, cardioprotection, antioxidant, and anti-inflammation. In addition, DHM inhibits the progression of cancers such as lung cancer, hepatocellular cancer, breast cancer, melanoma, and malignant reproductive systems through multiple mechanisms, including antiangiogenesis, antiproliferation, apoptosis, and inhibition of invasion and migration. Notably, DHM also activates autophagy at different levels, exerting a dual-regulatory effect on cancers. Mechanistically, DHM can effectively regulate mammalian target of rapamycin (mTOR), noncoding RNA-mediated signaling, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway, nuclear factor-κB (NF-κB), p53, and endoplasmic reticulum stress (ER stress)-driven signaling in different types of cancers. DHM has also been shown to have inhibitory effects on various regulators that trigger epithelial-mesenchymal transition (EMT). Furthermore, DHM exhibits a remarkable anticancer reversal ability when used in combination with drugs such as adriamycin, nedaplatin, and other drugs. However, the low bioavailability of DHM limits its potential applications, which are improved through structural modification and the exploration of novel dosage forms. Therefore, DHM may become a promising candidate for treating malignancies alone or combined with conventional anticancer strategies used in clinical practice.

3.
Se Pu ; 38(1): 127-136, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34213160

RESUMO

Magnetic amino functionalized metal-organic frameworks (MOFs) were prepared by a simple stirring and blending process. The obtained composites had good magnetic and thermal stability with a large specific surface area, and were used for the extraction of four preservatives with different polarities (benzoic acid, sorbic acid, propyl p-hydroxybenzoate and butyl p-hydroxybenzoate) in soda water, vitamin beverage and instant noodle cake samples. After optimizing the conditions for magnetic solid phase extraction (MSPE) and desorption, the four preservatives were analysed by a high performance liquid chromatography-ultraviolet detection (HPLC-UV) method. The analytes were separated on a Purospher® STAR LP C18 column (250 mm×4.6 mm, 5 µm). Methanol and 10 mmol/L ammonium acetate aqueous solution (50:50, v/v) were used as the mobile phases with gradient elution. The limits of detection of the four preservatives were 0.51-1.89 µg/L. The recoveries of the target preservatives were 72.2%-109% in the soda water, vitamin beverage and instant noodle cake samples. The method is simple, rapid, accurate and reliable, and is suitable for the analysis of preservatives with different polarities in beverages and foods. The method can provide an effective technology for food safety and quality control.

4.
Talanta ; 156-157: 126-133, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27260444

RESUMO

In this work, the metal-organic frameworks (MOFs), MIL-101-Cr-NH2 was synthesized via a direct hydrothermal method, and a polydimethylsiloxane (PDMS)/MIL-101-Cr-NH2 coated stir bar was prepared by sol-gel technique. Good reproducibility was obtained for the preparation of PDMS/MIL-101-Cr-NH2 coated stir bar with the relative standard deviations (RSDs) ranging from 3.7 to 5.2% (n=7) in one batch, and from 5.4 to 9.2% (n=7) among different batches. With the high surface area and rich benzene ring structure of MIL-101-Cr-NH2, the prepared PDMS/MIL-101-Cr-NH2 coated stir bar presented higher extraction efficiency for target organophosphorus pesticides (OPPs, including phorate, diazinon, malathion, fenthion, quinalphos and ethion) over PDMS coated stir bar. Based on it, a new method of PDMS/MIL-101-Cr-NH2 coated stir bar sorptive extraction (SBSE) coupled to gas chromatography-flame photometric detection (GC-FPD) was proposed for the determination of six OPPs in environmental water samples. The operation parameters affecting the extraction efficiency of SBSE, including extraction time, stirring rate, desorption time and ionic strength, were investigated. Under the optimal conditions, the limits of detection (S/N=3) were found to be in the range of 0.043-0.085µgL(-1) for the six target OPPs, and the linear range was 0.5-100µgL(-1) for malathion and 0.2-100µgL(-1) for other five OPPs. The RSDs of the proposed method evaluated at 1µgL(-1) for each OPP were in the range of 5.9-8.7% (intra-day, n=7) and 6.1-10.7% (inter-day, n=5), respectively. The enrichment factors were varied from 110 to 151-fold (theoretical enrichment factor was 200-fold). The proposed method was applied to the analysis of OPPs in East Lake and pond water samples with recoveries in the range of 89.3-115% and 80.0-113% for the spiked East Lake and pond water samples, respectively.


Assuntos
Fracionamento Químico/métodos , Cromatografia Gasosa/métodos , Dimetilpolisiloxanos/química , Estruturas Metalorgânicas/química , Compostos Organofosforados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Cromo/química , Complexos de Coordenação/química , Monitoramento Ambiental/métodos , Lagos/análise , Limite de Detecção , Compostos Organofosforados/isolamento & purificação , Praguicidas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
5.
Talanta ; 119: 458-66, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24401441

RESUMO

A novel Fe3O4@SiO2@polyaniline-graphene oxide composite (MPANI-GO) was prepared through a simple noncovalent method and applied to magnetic solid phase extraction (MSPE) of trace rare earth elements (REEs) in tea leaves and environmental water samples followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. The prepared MPANI-GO was characterized by transmission electron microscopy and vibrating sample magnetometer. Various parameters affecting MPANI-GO MSPE of REEs have been investigated. Under the optimized conditions, the limits of detection (LODs, 3σ) for REEs were in the range of 0.04-1.49 ng L(-1) and the relative standard deviations (RSDs, c=20 ng L(-1), n=7) were 1.7-6.5%. The accuracy of the proposed method was validated by analyzing a Certified Reference Material of GBW 07605 tea leaves. The method was also successfully applied for the determination of trace REEs in tea leaves and environmental water samples. The developed MPANI-GO MSPE-ICP-MS method has the advantages of simplicity, rapidity, high sensitivity, high enrichment factor and is suitable for the analysis of trace REEs in samples with complex matrix.


Assuntos
Compostos de Anilina/química , Grafite/química , Magnetismo , Espectrometria de Massas/métodos , Metais Terras Raras/análise , Dióxido de Silício/química , Oligoelementos/análise , Óxidos/química
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