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排序方式: 共有208条查询结果,搜索用时 15 毫秒
41.
We propose and demonstrate a dual-channel microfluidic sensor based on a side-hole fiber(SHF)with two longperiod fiber grating(LPFG)structures.There are two air holes in the SHF,which are natural microfluidic channels.We fabricate two LPFGs(long-period gratings LPG-A and LPG-B)in the SHF with the resonance wavelengths of 1268.7 nm and 1385.8 nm,respectively.Results show that the refractive index sensitivities of LPG-A and LPG-B are?76.0 nm/RIU and?71.1 nm/RIU,respectively.One can measure the refractive index of liquid samples in two channels simultaneously.The proposed dual-channel microfluidic sensor has advantages of good linearity response,fluidic technology compatibility,and easy light input/output coupling and system integration,which helps the sensor to have a potential application in environmental detection and food safety detection. 相似文献
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Cao Z Wang Z Herrmann C Landfester K Ziener U 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18008-18015
Hybrid particles containing different hydrophilic metal salts such as tetrafluoroborates of iron(II), cobalt(II), nickel(II), copper(II), and zinc(II), and nitrates of cobalt(II), nickel(II), copper(II), zinc(II), and iron(III), and cobalt(II) chloride were synthesized via inverse miniemulsion polymerization of 2-hydroxyethyl methacrylate (HEMA). All salts delivered narrowly size-distributed hybrid particles with the exception of iron(III), where only the nitrate salt could be successfully employed. The size and size distribution of the hybrid particles were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The particle morphology and the distribution of salt in the dried particles were observed by TEM. The influences of the type of metal salts and salt content on the particle size distribution were extensively investigated. 相似文献
44.
An improved Richardson-Lucy algorithm based on local prior 总被引:2,自引:0,他引:2
Ringing is one of the most common disturbing artifacts in image deconvolution. With a totally known kernel, the standard Richardson-Lucy (RL) algorithm succeeds in many motion deblurring processes, but the resulting images still contain visible ringing. When the estimated kernel is different from the real one, the result of the standard RL iterative algorithm will be worse. To suppress the ringing artifacts caused by failures in the blur kernel estimation, this paper improves the RL algorithm based on the local prior. Firstly, the standard deviation of pixels in the local window is computed to find the smooth region and the image gradient in the region is constrained to make its distribution consistent with the deblurring image gradient. Secondly, in order to suppress the ringing near the edge of a rigid body in the image, a new mask was obtained by computing the sharp edge of the image produced using the first step. If the kernel is large-scale, where the foreground is rigid and the background is smoothing, this step could produce a significant inhibitory effect on ringing artifacts. Thirdly, the boundary constraint is strengthened if the boundary is relatively smooth. As a result of the steps above, high-quality deblurred images can be obtained even when the estimated kernels are not perfectly accurate. On the basis of blurred images and the related kernel information taken by the additional hardware, our approach proved to be effective. 相似文献
45.
Reverse flow injection spectrophotometric determination of iodate and iodide in table salt 总被引:1,自引:0,他引:1
A very simple and sensitive reverse flow injection method is described for the determination of iodate and iodide. The iodate reacts with excess iodide in acidic medium to form tri-iodide, which can be spectrophotometrically monitored at 351 nm, and the absorbance is directly related to the concentration of iodate in the sample. The determination of iodide is based on oxidizing iodide to iodate. The calibration curve is linear in the range of 0.02-3.0 μg ml−1 I with r2=0.9998, and the limit of detection is 0.008 μg ml−1 I. The chemical and flow injection variables were studied and optimized to make the procedure suitable for quantitating iodate and iodide in table salts. It is shown that the reverse flow injection analysis could greatly improve the sensitivity and precision for determination of iodate with a relative standard deviation of 0.9%. A complete analysis, including sampling and washing, could be performed in 35 s. The procedure was applied successfully to the determination of iodate and iodide in table salts, and the results were statistically compared with results determined by standard iodometry method. 相似文献
46.
Langmuir-Blodgett膜(LB膜)具有特殊的功能和生物活性,在现代高技术中有广泛的应用[1]。本文合成了一个长链炔酸-8,10-二炔二十五碳酸,并研究其LB膜的聚合。 相似文献
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提出了基于垂直层叠结构的双波段传感器,该结构为同时对可见波段和近红外波段进行成像提供了可能。它的基本原理是利用不同波长的光在硅材料中穿透深度的非线性分布,即:短波长的可见光主要在表面被吸收,长波长的近红外光则主要在更深的位置被吸收。通过垂直层叠结构,抽取不同深度的光生载流子,即可以得到相应波段的成像信息。数值仿真分析表明,结构参量为D1=2μm,D2=18μm的结构能在400~1200 nm波长范围得到响应峰值波长为550 nm和1000 nm的最佳可见/近红外响应。 相似文献
49.
Yanfei Lü 《中国光学快报(英文版)》2007,5(7)
Efficient continuous-wave (CW) intracavity frequency doubling of a diode-end-pumped Nd:GdVO4 laser operating on 4F3/2 - 4I9/2 transitions at 912 nm has been demonstrated. A symmetrical cavity with two laser rods is designed, which divides the pump power between the two laser rods, allowing for greater power scalability. An 18-mm-long BiBO crystal, cut for critical type Ⅰ phase matching, is used for the intracavity frequency-doubled laser. A maximum output power of 6.2 W in the blue spectral range at 456 nm has been achieved with the pump power of 36 W. The beam quality M2 value is 2.5 in both horizontal and vertical directions. The ellipticity of the deep blue laser is 0.98, and the power stability is better than 3.2% at the maximum output power. 相似文献
50.