| 1. |
- Ma, Ming-Guo, et al.
(författare)
-
Fabrication and characterization of Ag/calcium silicate core-shell nanocomposites
- 2011
-
Ingår i: Materials letters (General ed.). - : Elsevier BV. - 0167-577X .- 1873-4979. ; 65:19-20, s. 3069-3071
-
Tidskriftsartikel (refereegranskat)abstract
- The Ag/calcium silicate nanocomposite with core-shell nanostructure has been successfully synthesized using Ag solution, Ca(NO(3))(2)center dot 4H(2)O and Na(2)SiO(3)center dot 9H(2)O in ethanol/water mixed solvents at room temperature for 48 h. Ag solution was previously prepared by microwave-assisted method in ethylene glycol (EG) at 150 degrees C for 10 min. The nanocomposites consisted of Ag core and an amorphous calcium silicate shell. The XRD and EDS results confirmed that the product was the Ag/calcium silicate nanocomposite. The TEM micrographs indicated that the Ag/calcium silicate nanocomposite was core-shell nanoparticles. The effects of Ca (NO(3))(2)center dot 4H(2)O and Na(2)SiO(3)center dot 9H(2)O concentration on the shells of Ag/calcium silicate nanocomposite were investigated. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive X-ray spectra (EDS). This method is simple, fast and may be extended to the synthesis of the other kinds of core-shell nanocomposites.
|
|
| 2. |
- Hu, Jing, et al.
(författare)
-
Hydrothermal preparation of boehmite-doped AgCl nanocubes and their characterization
- 2011
-
Ingår i: Materials letters (General ed.). - : Elsevier BV. - 0167-577X .- 1873-4979. ; 65:11, s. 1531-1534
-
Tidskriftsartikel (refereegranskat)abstract
- A simple hydrothermal route to the preparation of the boehmite-doped AgCl nanocubes using AgNO3,AlCl3 center dot 6H(2)O and NaOH at 200 degrees C for 24 h is reported. The products were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), UV-vis, thermogravimetric analysis (TGA), and differential thermal analysis (DTA). FE-SEM and TEM micrographs showed that the obtained boehmite-doped AgCl had nanocube-like morphology. The influence of heating temperature on the phase, microstructure, morphology, and thermal stability of the products were also investigated. UV-visible results indicated that the absorption edge moved to higher wavelength with the increasing heating temperature. These materials would be a promising material for photocatalyst applications.
|
|
| 3. |
- Jia, Ning, et al.
(författare)
-
Synthesis and characterization of cellulose-silica composite fiber in ethanol/water mixed solvents
- 2011
-
Ingår i: BioResources. - 1930-2126. ; 6:2, s. 1186-1195
-
Tidskriftsartikel (refereegranskat)abstract
- Cellulose-silica composite fiber samples have been successfully synthesized using cellulose solution, tetraethoxysilane, and NH3 center dot H2O in ethanol/water mixed solvents at room temperature for 24 h. The cellulose solution was previously prepared by the dissolution of microcrystalline cellulose in a solvent mixture of N,N-dimethylacetamide (DMAc)/lithium chloride (LiCl). The effect of the tetraethoxysilane concentration on the product was investigated. The products were characterized by X-ray powder diffraction (XRD), thermogravimetric analysis (TG), differential scanning calorimetric analysis (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR), energy-dispersive X-ray spectrum (EDS), and cross polarization magic angle spinning (CP/MAS) solid state C-13-NMR. The morphology of the cellulose-silica composite fiber was investigated by SEM, while their composition was established from EDS measurements combined with the results of FT-IR spectral analysis and XRD patterns. The XRD, FT-IR and EDS results indicated that the obtained product was cellulose-silica composite fiber. The SEM micrographs showed that the silica particles were homogeneously dispersed in the cellulose fiber. The CP/MAS solid state C-13-NMR results indicated that the silica concentration had an influence on the crystallinity of the cellulose. This method is simple for preparation of cellulose-based composites.
|
|
| 4. |
- Li, Shu-Ming, et al.
(författare)
-
Rapid microwave-assisted preparation and characterization of cellulose-silver nanocomposites
- 2011
-
Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 83:2, s. 422-429
-
Tidskriftsartikel (refereegranskat)abstract
- A simple rapid and efficient microwave-assisted synthesis of cellulose-silver nanocomposites with silver nanoparticles homogeneously dispersed in the cellulose matrix using cellulose solution AgNO3 and ascorbic acid in N N-dimethylacetamide (DMAc) is reported The cellulose solution was prepared by the dissolution of microcrystalline cellulose in a solvent system of lithium chloride (LiCl)/DMAc The effects of the microwave heating times and ascorbic acid concentration on the nanocomposites were investigated The microstructure size morphology and thermal properties of these nanocomposites were analyzed with X-ray diffraction (XRD) Fourier transform infrared (FT-IR) thermogravimetric analysis (TG) differential scanning calorimetric analysis (DSC) and scanning electron microscopy (SEM) The results revealed that the ascorbic acid concentration played an important role in the phase of the nanocomposites This work provided a promising way to prepare cellulose-silver nanocomposites with good dispersity.
|
|
| 5. |
- Xu, Tao, et al.
(författare)
-
Silicon-on-insulator nanopillar-array optical sensor
- 2011
-
Ingår i: Progress in Biomedical Optics and Imaging - Proceedings of SPIE. - : SPIE - International Society for Optical Engineering. - 9780819484451
-
Konferensbidrag (refereegranskat)abstract
- Pillar-array based optical cavities have unique properties, e.g., having a large and connected low dielectric index space (normally air space), having a large percent of electric field energy in air and standing on a substrate. These properties make them well suitable to make ultra compact and highly sensitive label-free optical sensors to detect bio-/chemical reactions. We designed, fabricated, and measured a silicon-on-insulator pillar array microcavity that possesses a quality factor as high as 27,600. We studied its sensitivity for both bulk index change and surface index modification. As a bulk index sensor, for environmental refractive index change of 0.01, a resonance peak wavelength shift of 3.5 nm was measured. As a surface index sensor, the simulations show, for a coating with thickness of 1 nm, the resonance wavelength shifts as large as 2.86 nm. Combining with a sharp 0.06 nm wide resonance peak, our pillar-array sensor is able to resolve ultra small bulk and surface refractive index changes caused by target molecules.
|
|
| 6. |
- Zhu, Chunhua, et al.
(författare)
-
TO901317 regulating apolipoprotein M expression mediates via the farnesoid X receptor pathway in Caco-2 cells
- 2011
-
Ingår i: Lipids in Health and Disease. - 1476-511X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Apolipoprotein M (apoM) may have potential antiatherosclerotic properties. It has been reported that apoM expression could be regulated by many intracellar and extracellar factors. In the present study we further investigated regulation of apoM expression in Caco-2 cells stimulated by a liver X receptor (LXR) agonist, TO901317. Materials and methods: Caco-2 cells were cultured in the presence of either TO901317, farnesoid X receptor (FXR) antagonist guggulsterone or TO901317 together with guggulsterone at different concentrations for 24 hrs. The mRNA levels of ATP-binding cassette transporter A1 (ABCA1), apoA1, apoM, liver receptor homologue-1 (LRH-1) and short heterodimer partner 1 (SHP1) were determined by real-time RT-PCR. Results: When Caco-2 cell cultured with TO901317 alone, the mRNA levels of ABCA1, apoA1, apoM, LRH-1 and SHP1 were significantly increased with dose-dependent manners (p < 0.05), whereas when the cells cultured with guggulsterone alone, the mRNA levels of apoM, SHP1 and LRH-1 (p < 0.05) were strongly inhibited. Moreover, guggulsterone could abolish the TO901317 enhanced mRNA levels of apoA1 apoM, SHP1 and LRH-1. Conclusion: The present study demonstrated that LXR agonist TO901317 induced apoM expression in Caco-2 cells might be mediated via the LXR/FXR pathway.
|
|
