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1.
Front Chem ; 9: 638216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307294

RESUMO

Inorganic nitride nanomaterials have attracted widespread attention for applications in renewable energy due to novel electrochemical activities and high chemical stabilities. For different renewable energy applications, there are many possibilities and uncertainties about the optimal nitride phases and nanostructures, which further promotes the exploration of controllable preparation of nitride nanomaterials. Moreover, unlike conventional nitrides with bulk or ceramic structures, the synthesis of nitride nanomaterials needs more accurate control to guarantee the target nanostructure along with the phase purity, which make the whole synthesis still a challenge to achieve. In this mini review, we mainly summarize the synthesis methods for inorganic nitride nanomaterials, including chemistry vapor deposition, self-propagation high-temperature synthesis, solid state metathesis reactions, solvothermal synthesis, etc. From the perspective of nanostructure, several novel nitrides, with nanostructures like nanoporous, two-dimensional, defects, ternary structures, and quantum dots, are showing unique properties and getting extensive attentions, recently. Prospects of future research in design and synthesis of functional inorganic nitrides are also discussed.

2.
Chem Commun (Camb) ; 56(9): 1436-1439, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31913370

RESUMO

An unexpected cascade reaction for oxidation-oximization of cyclohexane with ammonium acetate was developed for the first time to access cyclohexanone oxime with 50.7% selectivity (13.6% conversion). Tetrahedral Ti sites in Ni-containing hollow titanium silicalite can serve as bifunctional catalytic centers in the reaction. This methodology not only provides a direct approach to prepare cyclohexanone oxime, but also simplifies process chemistry. Various available nitrogen sources, such as ammonium salt and even ammonia can be used as starting materials.

3.
Se Pu ; 26(3): 306-9, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18724664

RESUMO

Single drop microextraction (SDME) was used for the determination of phthalate esters and parabens in drugs by gas chromatography-ion trap mass spectrometry (GC-IT/MS). The effects of the nature of extraction solvents, microdrop volume, the depth of microdrop in sample solution, extraction time and stirring rate on the extraction efficiency were investigated separately. The optimal SDME conditions, 1.5 microL of toluene, 0.8 cm of the depth of microdrop, 1 000 r/min of stirring rate and 20 mm of extraction time, were obtained and used for the analysis of methylparaben (MP), ethylparaben (EP), propylparaben (PP), iso-propylparaben (IPP), butylparaben (BP), dimethyl phthalate (DMP), diethyl phthalate (DEP) and dibutyl phthalate (DBP) in drugs. The results showed that the working curves for 8 phthalate esters and parabens were linear in the range of 0.032 - 80 mg/L by GC-MS on selective ion storage mode. The limits of detection (LOD) were between 0.6 microg/L and 1.28 mg/L, the overall recoveries were 95.85% - 148.85% with the relative standard deviations of 3.9% - 14.9%.


Assuntos
Fracionamento Químico/métodos , Ésteres/química , Parabenos/análise , Parabenos/isolamento & purificação , Preparações Farmacêuticas/química , Ácidos Ftálicos/análise , Ácidos Ftálicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Modelos Lineares , Ácidos Ftálicos/química , Solventes/química , Fatores de Tempo
4.
Se Pu ; 25(1): 35-8, 2007 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-17432572

RESUMO

A novel, simple, fast and environment-friendly method based on single drop microextraction (SDME) was developed for the determination of phthalate esters in food by gas chromatography-mass spectrometry (GC-MS). The effects of the nature of organic solvents, microdrop volume, the depth of microdrop in sample solution, extration time and stirring rate on the extraction efficiency were investigated separately. The optimal SDME conditions, 2.0 microL of toluene, 0.75 cm of the depth of microdrop, 1 000 r/min of stirring rate and 20 min of extraction time, were obtained and used for the analysis of dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), dioctyl phthalate (DOP) and diethylhexyl phthalate (DEHP) in food. At first, a sample was dissolved with de-ionized water and then extracted with ultrasonication for 15 min. Then, it was filtrated and the solution was extracted and concentrated by a single drop of a solvent. Finally, it was analyzed by GC-MS. The reproducibility, linearity, recovery, and limit of detection of the method were studied. The results showed that the limits of detection (LOD) were between 25 ng/L and 0.8 mg/L. The overall recoveries were 87.1% - 114.4% with the relative standard deviations of 4.9% - 11.6%. This method has been successfully applied to the analysis of food samples.


Assuntos
Ésteres/análise , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Ftálicos/química , Ésteres/química , Reprodutibilidade dos Testes , Extração em Fase Sólida
5.
Org Lett ; 8(14): 3017-20, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16805541

RESUMO

[reaction: see text] A novel and selective palladium-catalyzed annulation of 2-alkynylphenols method for the synthesis of 2-substituted 3-halobenzo[b]furans is presented. In the presence of PdX(2), CuX(2), and HEt(3)NX, 2-substituted 3-halobenzo[b]furans were selectively obtained as the major products. The mechanism of the reaction was also discussed.

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