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排序方式: 共有696条查询结果,搜索用时 15 毫秒
611.
本文根据单模光纤模场直径的横向位移定义,提出了一种测量模场直径的新方法——远场高斯掩模匹配法.讨论了几种测量及数据处理方法.最后给出了初步的实验结果. 相似文献
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Heated electrodes were applied for the non-isothermal operation of amperometric glucose biosensors based on glucose oxidase immobilised on the electrode surface by entrapment within a polymer layer. The localised deposition of the polymer film under simultaneous entrapment of the enzyme was achieved by an electrochemically induced pH-modulation in the diffusion zone in front of the electrode, thus altering the solubility of the polymer chains. This non-manual sensor preparation protocol could be successfully used for the modification of a novel indirectly heated electrode. The non-isothermal operating mode allows working at the optimum temperature of the enzyme sensors without any thermal distortion of the bulk solution. Increased surface temperature of the sensor thus accelerates transport as well as kinetic processes, resulting in an enhanced amperometric signal.In the presence of interfering compounds such as ascorbic acid, the proposed technique allows use of the diverging thermal impact on the sensing process, for different electrochemically active compounds, for a deconvolution of the amperometric signal at different electrode temperatures. A calculation method for determination of glucose in the presence of one interfering compound is presented as a basis for a calculative interference elimination. 相似文献
615.
《Electroanalysis》2003,15(12):1023-1030
The coenzyme FAD has been identified to play an important role in the detection mechanism of oxidase enzyme based biosensors. Incorporating FAD into the carbon composite improved sensitivity to H2O2 consequently increasing sensitivity to the respective analyte. The amount of active enzyme also increased thus enhancing the overall performance of the sensors. Polycarboxybetaine (PCB) has been used as a biocompatible membrane coating. The PCB coated sensors gave reproducible calibrations in protein solutions, which has been shown to be a valid protocol for testing biocompatibility. The importance of reporting selectivity in a manner which indicates the “fitness of purpose” of biosensors has been discussed. 相似文献
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介绍了利用ICP-AES对玩具中有害重金属元素的分析研究。文中详述了实验方法、适用范围以及结果和讨论,并运用干扰系数法校正元素间光谱干扰,结果较为满意,这在玩具日常检验的光谱分析中具有重要的实际意义。 相似文献
618.
Artificial neural networks (ANNs) are among the most popular techniques for nonlinear multivariate calibration in complicated mixtures using spectrophotometric data. In this study we propose a computer-based method for removing Te(IV) interference in the determination of Se(IV) using artificial neural networks. In this way, an artificial neural network consisting of three layers of nodes was trained by applying a back-propagation learning rule. The resulting RMSE of prediction for selenium was obtained as 0.108. 相似文献
619.
W. Winkler K. Danzmann H. Grote M. Hewitson S. Hild J. Hough H. Lück M. Malec A. Freise K. Mossavi S. Rowan A. Rüdiger R. Schilling J.R. Smith K.A. Strain H. Ward B. Willke 《Optics Communications》2007,280(2):492-499
The optical layout of the interferometric gravitational wave detector GEO600 is described in detail. Criteria for the choice of the geometry of this power- and signal recycled interferometer are presented, including the beam shape inside the interferometer and the surface figure of the optical components. Light power limits for the present setup are discussed. In addition, the demands for the mode cleaners and their performance are given. 相似文献
620.
D. Bar 《International Journal of Theoretical Physics》2007,46(10):2626-2657
The double slit experiment (DSE) is known as an important cornerstone in the foundations of physical theories such as Quantum
Mechanics and Special Relativity. A large number of different variants of it were designed and performed over the years. We
perform and discuss here a new version with the somewhat unexpected results of obtaining interference pattern from single-slit
screen. We show using either the Brill’s version of the canonical formulation of general relativity or the linearized version
of it that one may find corresponding and analogous situations in the framework of general relativity. 相似文献