漫谈长虹电视机防蓝光护眼方案设计

现在蓝光对人眼的影响成为社会关注的话题,而电视机防蓝光作为一种健康时尚功能正成为一种潮流。本文主要介绍了蓝光对人眼的影响以及长虹防蓝光电视机的全方位设计方案。

Spectroscopic Studies of the Interaction of Silver Nanoparticles with Methylene Blue

The interaction between silver nanoparticles and Methylene Blue （MB） is studied by UV-Vis spectroscopy and fluorescence spec- trometry. The UV-Vis absorption of the silver nanoparticles changes dramatically with the addition of MB. However, no obvious changes of absorption spectra of MB are observed when silver colloids are added into the MB solution. In the presence of surfactant SDS, the catalysis of the silver nanoparticles in the reduction of MB by sodium borohydride is exhibited by UV-Vis and fluorescence spectrosopy of MB displaying faster response compared with the absence of the silver nanoparticles. The results show that the activity of surfactant SDS modified silver nanoparticles is great and a strong physical adsorption to MB exists.

Investigation of spectrum blue shift in organic quantum well electroluminescent devices

In this paper, the organic quantum well devices,which are similar to the type-Ⅱ quantum well of inorganic semiconductor, have been fabricated, in which the NPB (N,N’-Di-[(1-naphthalenyl)-N,N’-diphenyl]-(1,1’-biphenyl)-4,4’-diamine) and Alq3 (Tris-(8-quinolinolato)aluminum) act as the potential barrier layer and the potential well layer, respectively. In the electroluminescence, the blue shift of spectrum with the decreasing of well width is observed for the device with different well width, and this is interpreted by combination of quantum size effect and exciton confinement effect. The blue shift of spectrum with increasing applied voltage is observed for the same device, and this is interpreted in terms of polarization effect and quantum size effect.

C2H2 Overtones Near 12300 cm^-1 Revisited with a Very Sensitive Cavity Ring-down Spectrometer

A cavity ring-down spectrometer （CRDS） is constructed with a single-mode continuous-wave Ti：Sapphire laser. It allows attaining a minimum detectable absorption of 1.8× 10^-10cm^-1. The spectrometer is applied to record the overtone spectrum of ^12C2H2 in the 12240- 12350 cm-1. Compared with the previous CRDS and intra-cavity laser absorption spectroscopy studies in the same region, the present measurement achieved better sensitivity and better precision as well. As a result, the ro-vibrational parameters of the high overtone bands of acetylene at 12290.12, 12311.82, and 12350.61 cm^-1 have been refined. The advantages of the present CRD spectrometer is also demonstrated by the newly observed and well characterized perturbation on the f component of the very weak band near 12289 cm^-1. The quantitative measurement capability of the spectrometer is verified with the measurement of the water lines and employed to give the absolute band intensities of those three acetylene bands.

LED在博物馆和美术馆中的应用

在博物馆照明中，LED提供了一种既节约能源消耗，又降低维护成本，可替代卤素光源的选择。之前，高色温荧光粉校正单色白光LED在光谱的完整性方面存在缺陷，导致对真实色彩的还原性较差，并且在某些遗产保护项目中，对光敏物质照明时，其中的蓝光光谱的峰值、衰减和光通量都不甚理想。

Efficient broadband near-infrared phosphor Sr_(2)ScSbO_(6):Cr^(3+) for solar-like lighting

For healthy lighting,daily lighting that considers both visible light and near-infrared(NIR)light is necessary.However,at~900 nm,the extensively used solar-like phosphor-converted light-emitting diodes(pc-LEDs)are limited by a lack of high-performance NIR luminescent materials.We report a broadband NIR phosphor Sr_(2)ScSbO_(6):Cr^(3+) with a double perovskite-type structure,thus simultaneously demonstrating high luminescence efficiency and good thermal stability.Under 550-nm excitation,Sr_(2)ScSbO_(6):Cr^(3+) demonstrates broadband NIR emission centered at~890 nm with luminescence internal/external efficiencies of 82.0%/35.7%,respectively.Furthermore,the luminescence integrated intensity at 430 K remains at~66.4% of the initial intensity.We successfully fabricated pc-LED devices using a 465-nm-sized blue chip and other commercial phosphors,presenting a relatively complete solar-like spectrum from blue to NIR light and is expected to be used in solar-like lighting.

Light emission properties of sapphire under shock loading in the stress range of 40-120 GPa

The measurement of emissions from the window material of sapphire was performed through multi-wavelength pyrometer and spontaneous spectroscopic techniques in the pressure range of 40 -120 GPa. The results showed that the spectral distribution with wavelength clearly fit well with the grey-body spectrum. We have analyzed the emissions and discovered they mostly came from the shear banding, which is a typical thermal radiation. The radiance intensity changing linearly with time revealed it was a volume effect. All of the data from pyrometer can be explained by the model of Boslough＇s study, especially for pres- sures over megabar. The color temperature of shocked sapphire changing with increased stress disagrees with the computed melt curve which is likely explained by the differcnt phase structures of sapphire.

Tunable ultraviolet to deep blue light emission from sulfur nanodots fabricated by a controllable fission-aggregation strategy

Bright tunable light emission in the short wavelength range from sulfur nanodots was demonstrated with a photoluminescence quantum yield(PLQY)of up to 59.4%.A fission-aggregation mechanism was proposed for the formation of sulfur nanodots with desired performances.This synthetic strategy allowed for simultaneous size control from 3.2 to 5.6 nm,thus tuning the emission color from ultraviolet(UV)to deep blue(342±430 nm),and for the suppression of unwanted nonradiative recombination centers and deep level emission.The luminescence mechanism and quantum confinement effect of the synthesized sulfur nanodots were investigated by optical spectroscopy and theoretical calculations.These results show promise toward the application of sulfur nanodots in UV optoelectronics,biomedical treatments,and sterilization.