We report the surface-enhanced Raman (SERS) spectra of morphine in silver colloid, and study the silver colloid enhanced effects on the Raman scattering of morphine. The Raman bands of morphine are assigned to certa...We report the surface-enhanced Raman (SERS) spectra of morphine in silver colloid, and study the silver colloid enhanced effects on the Raman scattering of morphine. The Raman bands of morphine are assigned to certain molecule vibrations. The broad band in the long-wavelength region of the electronic absorption spectra of the sol with added adsorbent at certain concentrations has been explained in terms of the ag- gregation of the colloidal silver particles. The potential applications of SERS in quantitative measurement of the morphine samples are demonstrated. By using a proper Raman band of morphine, the detection limit of morphine in silver sol is found to be 1.5 ng/ml. The result suggests that it is of great significance to use SERS in illicit drug morphine inspection.展开更多
Vanadium oxide nanotubes were synthesized by hydrothermal treatment from V2O5·nH2O sols as precursor and dodecylamine as structure-directing template. The morphology and structure of the nanotubes were characteri...Vanadium oxide nanotubes were synthesized by hydrothermal treatment from V2O5·nH2O sols as precursor and dodecylamine as structure-directing template. The morphology and structure of the nanotubes were characterized by SEM, TEM, XRD, TG-DTA and FTIR. The experimental results reveal that the duration of the hydrothermal treatment is of importance for obtaining VOx-NTs which have a layered structure. TG-DTA study indicates that V5+ cations in nanotubes are partially reduced to V4+ cations. The results from FTIR spectra indicate the difference in V-O vibrations between before and after hydrothermal treatment. From the results, it suggests that during hydrothermal treatment, the rearrangement of the vanadium oxide structure leads to the formation of VOx nanotubes from lamellar structure because of the presence of V4+ species.展开更多
We report a new structure for broadband antireflection coating by dip-coating technique, which has minimal cost and is compatible with large-scale manufacturing. The coatings are prepared by depositing SiO2 sol-gel fi...We report a new structure for broadband antireflection coating by dip-coating technique, which has minimal cost and is compatible with large-scale manufacturing. The coatings are prepared by depositing SiO2 sol-gel film on a glass substrate, subsequently depositing SiO2 single-layer particle coating through electrostatic attraction, and depositing a final very thin SiO2 sol-gel film to improve the mechanical strength of the whole coating structure. The refractive index of the structure changes gradually from the top to the substrate. The transmittance of a glass substrate has been experimentally found to be improved in the spectral range of 400-1 400 nm and in the incidence angle range from 0° to at least 45°. The mechanical strength is immensely improved because of the additional thin SiO2 sol-gel layer. The surface texture can be applied to the substrates of different materials and shapes as an add-on coating.展开更多
A new organic-inorganic hybrid material,which shows photo-induced reduction of refractive index as well as volume contraction,is prepared using a sol-gel method.This material is coated on a Si substrate by spin-coatin...A new organic-inorganic hybrid material,which shows photo-induced reduction of refractive index as well as volume contraction,is prepared using a sol-gel method.This material is coated on a Si substrate by spin-coating to manufacture film.After irradiated by ultraviolet(UV) light with a deuterium lamp for 5 h, the thickness of film decreases largely by 55%,and the refractive index of film changes from 1.484 to 1.445 at 550 nm.The film's optical thickness exhibits an exponential change with the increasing irradiation time.Futhermore.the photo-patternning of the organic-inorganic hybrid film without any further process (wet etching and thermal curing) is performed utilizing the volume contraction on UV-light irradiation. This film has potential applications for fabrication of patterned filter array and apodizing filter by direct light writing,and also demonstrates good temperature stability and immunity to visible light exposure.展开更多
In order to improve the laser-induced damage threshold (LIDT) of the ZrO2 film, the effect of polyvinyl pyrrolidone (PVP) with different average molecular weight on coatings is studied. The ZrO2 sol is prepared by...In order to improve the laser-induced damage threshold (LIDT) of the ZrO2 film, the effect of polyvinyl pyrrolidone (PVP) with different average molecular weight on coatings is studied. The ZrO2 sol is prepared by the hydrolysis of zirconium n-propoxide with acetylacetone as the chelating agent. The PVP (K16-18) is more suitable to obtain high LIDT coatings than other PVPs. The LIDT of the ZrO2-PVP coatings is improved with the increase of the PVP (K16-18) content. When the PVP (K16-18) content is 2.4 wt.-~0, the LIDT of the ZrO2-PVP coatings is 43.5 J/cm2 (1064 nm, 12 ns). The ZrO2 sol and ZrO2-PVP (K16- 18) sol have the good stability in 3 months. The refractive indices of the ZrO2-PVP coatings decrease with the increase of the PVP (K16-18) content.展开更多
基金supported by the National Natural Science Fundation of China (No.60778046)the Project of Fujian Province (Nos.2008I0015 and 2008J0016)+1 种基金the Project of Fujian Key Lab of Semiconductors and Applications,Xiamen Universitythe Project of Fujian Development and Reform Commission (No.2005-847)
文摘We report the surface-enhanced Raman (SERS) spectra of morphine in silver colloid, and study the silver colloid enhanced effects on the Raman scattering of morphine. The Raman bands of morphine are assigned to certain molecule vibrations. The broad band in the long-wavelength region of the electronic absorption spectra of the sol with added adsorbent at certain concentrations has been explained in terms of the ag- gregation of the colloidal silver particles. The potential applications of SERS in quantitative measurement of the morphine samples are demonstrated. By using a proper Raman band of morphine, the detection limit of morphine in silver sol is found to be 1.5 ng/ml. The result suggests that it is of great significance to use SERS in illicit drug morphine inspection.
基金This work was financially supported by the National Natural Science Foundation of China (No.50402024)the Natural Science Foundation of Gansu Province (No.ZS041-A25-033).
文摘Vanadium oxide nanotubes were synthesized by hydrothermal treatment from V2O5·nH2O sols as precursor and dodecylamine as structure-directing template. The morphology and structure of the nanotubes were characterized by SEM, TEM, XRD, TG-DTA and FTIR. The experimental results reveal that the duration of the hydrothermal treatment is of importance for obtaining VOx-NTs which have a layered structure. TG-DTA study indicates that V5+ cations in nanotubes are partially reduced to V4+ cations. The results from FTIR spectra indicate the difference in V-O vibrations between before and after hydrothermal treatment. From the results, it suggests that during hydrothermal treatment, the rearrangement of the vanadium oxide structure leads to the formation of VOx nanotubes from lamellar structure because of the presence of V4+ species.
文摘We report a new structure for broadband antireflection coating by dip-coating technique, which has minimal cost and is compatible with large-scale manufacturing. The coatings are prepared by depositing SiO2 sol-gel film on a glass substrate, subsequently depositing SiO2 single-layer particle coating through electrostatic attraction, and depositing a final very thin SiO2 sol-gel film to improve the mechanical strength of the whole coating structure. The refractive index of the structure changes gradually from the top to the substrate. The transmittance of a glass substrate has been experimentally found to be improved in the spectral range of 400-1 400 nm and in the incidence angle range from 0° to at least 45°. The mechanical strength is immensely improved because of the additional thin SiO2 sol-gel layer. The surface texture can be applied to the substrates of different materials and shapes as an add-on coating.
基金supported by the National Natural Science Foundation of China(Nos.60708013 and 60778025)the China Post-Doctoral Funding(No.20081463)the Zhejiang Provincial Natural Science Foundation(No. Y5080094)
文摘A new organic-inorganic hybrid material,which shows photo-induced reduction of refractive index as well as volume contraction,is prepared using a sol-gel method.This material is coated on a Si substrate by spin-coating to manufacture film.After irradiated by ultraviolet(UV) light with a deuterium lamp for 5 h, the thickness of film decreases largely by 55%,and the refractive index of film changes from 1.484 to 1.445 at 550 nm.The film's optical thickness exhibits an exponential change with the increasing irradiation time.Futhermore.the photo-patternning of the organic-inorganic hybrid film without any further process (wet etching and thermal curing) is performed utilizing the volume contraction on UV-light irradiation. This film has potential applications for fabrication of patterned filter array and apodizing filter by direct light writing,and also demonstrates good temperature stability and immunity to visible light exposure.
基金supported by the High-Tech Research and Development Program of China(No.8638042).
文摘In order to improve the laser-induced damage threshold (LIDT) of the ZrO2 film, the effect of polyvinyl pyrrolidone (PVP) with different average molecular weight on coatings is studied. The ZrO2 sol is prepared by the hydrolysis of zirconium n-propoxide with acetylacetone as the chelating agent. The PVP (K16-18) is more suitable to obtain high LIDT coatings than other PVPs. The LIDT of the ZrO2-PVP coatings is improved with the increase of the PVP (K16-18) content. When the PVP (K16-18) content is 2.4 wt.-~0, the LIDT of the ZrO2-PVP coatings is 43.5 J/cm2 (1064 nm, 12 ns). The ZrO2 sol and ZrO2-PVP (K16- 18) sol have the good stability in 3 months. The refractive indices of the ZrO2-PVP coatings decrease with the increase of the PVP (K16-18) content.