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1.
Bioorg Med Chem Lett ; 85: 129239, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36924947

RESUMEN

A series of 5' monosubstituted chalcone derivatives were synthesized to explore their antitumor activity and mechanism of action in vitro. The structures of 5' monosubstituted chalcone derivatives synthesized by reactions such as Suzuki coupling were confirmed by 1H NMR, 13C NMR and MS, and the target compounds were not reported in the literature. The antitumor activity of the aimed compounds was tested by MTT colorimetric method in vitro. Compound 5c has an IC50 value of 1.97 µM for K562 and a value of 2.23 µM for HepG2. Further investigation of the mechanism of action of compound 5c was found to have effects on K562 cell morphology, proliferation, apoptosis, cell cycle, and wound healing of HepG2 cells. The results showed that compound 5c has research value in antitumor activity and mechanism of action in vitro.


Asunto(s)
Antineoplásicos , Chalcona , Chalconas , Chalcona/química , Chalconas/química , Relación Estructura-Actividad , Proliferación Celular , Antineoplásicos/química , Apoptosis , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular Tumoral , Estructura Molecular
2.
Small ; 18(23): e2200405, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35557485

RESUMEN

Purposeful control of the highly active crystal planes is an effective strategy to improve the nanocrystalline catalytic activity. Therefore, Co2 P nanocrystals with high exposure of (211) lattice plane loaded at 2D hexagonal V2 O3 nanosheets (H-Co2 P-V2 O3 ) are designed via the control of morphology. After optimization, this H-Co2 P-V2 O3 boosts the redox kinetics of lithium polysulfides (LiPSs) in lithium-sulfur batteries (LSBs), which is due to the increase of the Co-active sites by exposing more (211) lattice planes of Co2 P, and the high adsorption and catalysis characteristic of H-Co2 P-V2 O3 for the conversion of LiPSs into LSBs. In the case of modification separator by H-Co2 P-V2 O3 composite, the battery achieves an outstanding reversibility of 876.9 mAh g-1 over 500 cycles at 1 C, a superior rate property of 611.5 mAh g-1 at 8 C, and a long-term cycling performance with a low attenuation of 0.04% per cycle over 1000 cycles at 4 C for LSBs. Impressively, a remarkable areal capacity of 12.38 mAh cm-2 is retained under the high sulfur loading of 14.5 mg cm-2 after 100 cycles. It is believed that the crystal surface engineering provides guidance to further improve the electrochemical performance of the LSB field.

3.
J Chromatogr A ; 1604: 460473, 2019 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-31472937

RESUMEN

A solvent-assisted vacuum desorption method is developed and combined with gas chromatography-tandem mass spectrometry (GC-MS/MS) for quick determination of soil PAHs. With the assistance of a reduced pressure of 0.0001 kPa and the DMSO/acetone (1:1) mixed solvent, this method allows desorption of PAHs in a moderate temperature of 160 °C. Analytes were trapped in a collection tube and eluted with n-hexan for GC-MS/MS analysis. The entire procedure can be completed within 20 min. In order to validate this method for determining soil PAHs, the solvent-assisted vacuum desorption method, Soxhlet extraction and ASE extraction were applied in different samples of real contaminated soils. Most HMW PAHs showed similar concentrations, yet LMW PAHs with solvent-assisted vacuum desorption presented significantly higher concentrations than those with conventional methods, such as NAP, ANY, ANA and FLU. Further investigation revealed that solvent-assisted vacuum desorption is capable of improving both the extractability and collection efficiency of those four LMW PAHs in real contaminated soil. This method enables desorption of HMW PAHs and provides the additional benefit of improved extractability and collection efficiency for LMW PAHs.


Asunto(s)
Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes del Suelo/análisis , Suelo/química , Solventes/química , Vacio
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 1-5, 2016 Jan.
Artículo en Chino | MEDLINE | ID: mdl-27228729

RESUMEN

Resonate frequency and cell constant of photoacoustic spectrum system are usually calibrated by using standard gas in laboratory, whereas the resonate frequency and cell constant will be changed in-situ, leading to measurement accuracy errors, caused by uncertainties of standard gas, differences between standard and measured gas components and changes in environmental condition, such as temperature and humidity. As to overcome the above problems, we have proposed an on-line atmospheric oxygen-based calibration technology for photoacoustic spectrum system and used in measurement of concentration of carbon dioxide in atmosphere. As the concentration of atmospheric oxygen is kept as constant as 20.96%, the on-line calibration for the photoacoustic spectrum system can be realized by detecting the swept-frequency and peak signal at 763.73 nm. The cell of the PAS has a cavity with length of 100 mm and an inner diameter of 6 mm, and worked in a first longitudinal resonant mode. The influence of environmental temperature and humidity, gas components on the photoacoustic cell's performance has been theoretically analyzed, and meanwhile the resonant frequencies and cell constants were calibrated and acquired respectively using standard gas, indoor air and outdoor air. Compared with calibrated gas analyzer, concentration of carbon dioxide is more accurate by using the resonant frequency and cell constant calculated by oxygen in tested air, of which the relative error is less than 1%, much smaller than that calculated by the standard gas in laboratory. The innovation of this paper is that using atmospheric oxygen as photoacoustic spectrum system's calibration gas effectively reduces the error caused by using standard gas and environmental condition changes, and thus improves the on-line measuring accuracy and reliability of the photoacoustic spectrum system.

5.
Ying Yong Sheng Tai Xue Bao ; 19(4): 752-6, 2008 Apr.
Artículo en Chino | MEDLINE | ID: mdl-18593033

RESUMEN

The study on the characteristics of cadmium (Cd) and zinc (Zn) absorption and distribution in 11 tree species in a mining area of Nanjing showed that the absorption and accumulation of test heavy metals differed with tree species, their organs, and heavy metals themselves. Among the test tree species, Viburnum awabuki had the highest Cd absorption, accumulation, and translocation rates, which could be used for the remediation of polluted soils via phytoextraction. Cd was mainly accumulated in tree roots, and its accumulation in tree organs was generally in the order of root > leaf and shoot > bark > stem. Zn was generally accumulated in above-ground part, such as in leaf and shoot, but not in root. For the test 11 tree species, the accumulation coefficients of Cd and Zn were all less than 0.2, while the translocation coefficients differed markedly, with that of Zn being higher than that of Cd in general.


Asunto(s)
Cadmio/metabolismo , Minería , Contaminantes del Suelo/metabolismo , Árboles/metabolismo , Zinc/metabolismo , Biodegradación Ambiental , Cadmio/análisis , China , Hierro , Raíces de Plantas/metabolismo , Contaminantes del Suelo/análisis , Especificidad de la Especie , Zinc/análisis
6.
Appl Opt ; 47(4): 504-11, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18239709

RESUMEN

A refractive index sensor based on the thinned and microstructure fiber Bragg grating (ThMs-FBG) was proposed and realized as a chemical sensing. The numerical simulation for the reflectance spectrum of the ThMs-FBG was calculated and the phase shift down-peak could be observed from the reflectance spectrum. Many factors influencing the reflectance spectrum were considered in detail for simulation, including the etched depth, length, and position. The sandwich-solution etching method was utilized to realize the microstructure of the ThMs-FBG, and the photographs of the microstructure were obtained. Experimental results demonstrated that the reflectance spectrum, phase shift down-peak wavelength, and reflected optical intensity of the ThMs-FBG all depended on the surrounding refractive index. However, only the down-peak wavelength of the ThMs-FBG changed with the surrounding temperature. Under the condition that the length and cladding diameter of the ThMs-FBG microstructure were 800 and 14 mum, respectively, and the position of the microstructure of the ThMs-FBG is in the middle of grating region, the refractive index sensitivity of the ThMs-FBG was 0.79 nm/refractive index unit with the wide range of 1.33-1.457 and a high resolution of 1.2 x 10(-3). The temperature sensitivity was 0.0103 nm/ degrees C, which was approximately equal to that of common FBG.


Asunto(s)
Técnicas Biosensibles/instrumentación , Diseño Asistido por Computadora , Tecnología de Fibra Óptica/instrumentación , Análisis de Inyección de Flujo/instrumentación , Modelos Teóricos , Refractometría/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Análisis de Inyección de Flujo/métodos , Miniaturización , Refractometría/métodos
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