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A compact folded three-mirror cavity with length of 100 mm is optimized to obtain high efficient 457 nm laser. When the incident pump power into Nd:YVO4 is 16.3 W, as high as 1.52 W continuous wave 457 nm blue laser is achieved by LBO intracavity frequency doubled. The optical-to-optical conversion efficiency is greater than 9.3%. 相似文献
114.
《Electrophoresis》2018,39(11):1357-1360
We previously found that multimeric GlyT1aN16 protein exhibits increased diffusion in a polyacrylamide gel and shows an unusual time‐dependent absorbance rearrangement, as revealed by the Bradford assay. Here, we find that glycine to alanine mutation eliminates the absorbance shift, but not the altered diffusion properties of GlyT1aN16, indicating that these two phenomena are not interconnected. The absorbance shift is apparent with both native and urea‐denatured GlyT1aN16, suggesting that the effect is either not dependent on protein structure, or the required structure is restored very quickly following denaturant removal. In the far‐UV spectra, circular dichroism (CD) curves for both wild‐type and mutated GlyT1aN16 are under the zero line, indicating largely unstructured character. However, a significant shift of the mutant CD curve suggests possible microstructural heterogeneity. Deconvolution of the CD data indicates a potential 3‐fold increase in isolated helical content, which would inhibit an absorbance shift, as we demonstrated previously. These results suggest that, in addition to protein quantification, Coomassie Brilliant Blue G‐250 can be used to reveal certain properties of the secondary structure of proteins. 相似文献
115.
A single-cell-gap transflective polymer-stabilised blue-phase liquid crystal display with opposite polar pixel electrodes on an etched substrate is proposed. In the proposed structure, the space between common electrodes is adopted as transmissive region, and the space above the common electrode is adopted as reflective region. By optimising the electrode parameters of the transmissive and reflective regions, well-matched voltage-dependent transmittance and reflectance curves can be obtained. In addition, the device has good performances of low operating voltage (~3.2 V), high optical efficiency and a wide viewing angle. 相似文献
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117.
《Electroanalysis》2003,15(3):219-224
A novel hydrogen peroxide biosensor has been constructed based on the characteristics of the carbon nanotube. The multiwall carbon nanotube (MWNT) was used as a coimmobilization matrix to incorporate horseradish peroxidase (HRP) and electron transfer mediator methylene blue (MB) onto a glassy carbon electrode surface. Cyclic voltammetry and amperometric measurements were employed to demonstrate the feasibility of methylene blue as an electron carrier between the immobilized peroxidase and the surface of glassy carbon electrode. The amperometric response of this resulting biosensor to H2O2 shows a linear relation in the range from 4 μM to 2 mM. The detection limit was 1 μM when the signal to noise ratio is 3. The presence of dopamine and ascorbic acid hardly affects the sensitive determination of H2O2. This biosensor also possesses very good stability and reproducibility. 相似文献
118.
Mary Kamburova 《Mikrochimica acta》1998,128(3-4):177-180
The interaction of Cr(VI) and Nitrotetrazolium Blue has been examined. A 12 NTB (CrO3Cl)2 ion-associate is formed and is extractable into 1,2-dichloroethane. The optimum conditions have been established. The molar absorptivity at 260 nm was (8.2 ± 0.06) × 104L mol–1cm–1. Beer's law was obeyed in the range 0.01–0.4 g ml–1 Cr(VI). A sensitive and selective method for determination of micro-quantities of Cr(VI) in soils and steels is suggested. 相似文献
119.
Toluidine Blue O (TBO) was covalently bound on silica gel and mixed with graphite powder and paraffin oil to produce modified carbon paste electrodes. The formal potential (E°′) of the covalently bound TBO was found to be −100 mV versus Ag|AgCl (KCl sat.) at pH 7.0 and the E°′ varied less than anticipated for a 2-electron-proton type mediator with pH. The bound TBO was found to act as an efficient electron acceptor for NADH as well as electron donor for oxidised horseradish peroxidase (HRP). The kinetics and the mechanism of the reaction between NADH and TBO were investigated with cyclic voltammetry and using a rotating disc electrode. Further experiments were done in the flow injection mode injecting different concentrations of NADH. Similar studies were done in the presence of hydrogen peroxide when HRP was adsorbed onto the TBO modified silica gel carbon paste electrodes. 相似文献
120.
Hongzhen Lian Danni Li Sizhu Mei Xiaojiang Wu Xiancong Tao Yijun Chen Lemei Dai Ning Gan Liching Tian 《Analytica chimica acta》2004,511(1):25-31
A novel strategy for the speciation of aluminum has been developed by fluorometry using selective analytical reagents under different pH conditions, which is based on the measurement of the complexation ability of Al for analytical reagents and native organic matters. With Eriochrome Blue Black R, labile monomeric Al and total monomeric Al fractions are determined at pH 4.5 and pH 8.0, respectively. With morin only the labile monomeric Al is determined at pH 4.0, while with 8-hydroxyquinoline the total monomeric Al is determined at pH 5.5. So, acid soluble Al fraction is obtained indirectly. This method is successfully applied to the fractionation of Al in natural waters. The results well agree with those obtained by Driscoll’s 8-hydroxyquinoline/cation-exchange protocol. This fluorometric method possesses some advantages such as high sensitivity, easy manipulation, no separation step and less time-consuming. 相似文献