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991.
992.
利用菲涅耳双镜测金属线膨胀系数 总被引:2,自引:0,他引:2
分析了菲涅耳双镜在干涉实验中 ,由金属受热膨胀引起的光源位置变化对干涉条纹的影响 ,导出金属受热时绝对伸长量与干涉条纹位置变化之间的关系 ,并通过它对黄铜棒的线膨胀系数进行测量。 相似文献
993.
994.
The ability to control propagation of electromagnetic guided modes lies at the heart of integrated nanophotonics. Surface plasmon‐polaritons are a class of guided modes which can be employed in integrated optical systems. Here, we present a theoretical design of a coherent surface plasmon absorber which can perfectly harvest energy of coherently incident surface plasmons without parasitic scattering into free space modes. Excitation of free space modes which usually accompanies scattering of a surface plasmon by an interface boundary is avoided due to specially tailored anisotropy of the absorber. The concept of coherent SPP absorber is analyzed numerically for spatially non‐uniform and finite‐size structures. We believe that our results will be important for the development of integrated nanoplasmonic systems. 相似文献
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996.
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Morgana B. Dessuy Maria Goreti R. Vale Fábio G. Lepri Daniel L.G. Borges Bernhard Welz Márcia M. Silva Uwe Heitmann 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
The artifacts created in the measurement of phosphorus at the 213.6-nm non-resonance line by electrothermal atomic absorption spectrometry using line source atomic absorption spectrometry (LS AAS) and deuterium lamp background correction (D2 BC) have been investigated using high-resolution continuum source atomic absorption spectrometry (HR-CS AAS). The absorbance signals and the analytical curves obtained by LS AAS without and with D2 BC, and with HR-CS AAS without and with automatic correction for continuous background absorption, and also with least-squares background correction for molecular absorption with rotational fine structure were compared. The molecular absorption due to the suboxide PO that exhibits pronounced fine structure could not be corrected by the D2 BC system, causing significant overcorrection. Among the investigated chemical modifiers, NaF, La, Pd and Pd + Ca, the Pd modifier resulted in the best agreement of the results obtained with LS AAS and HR-CS AAS. However, a 15% to 100% higher sensitivity, expressed as slope of the analytical curve, was obtained for LS AAS compared to HR-CS AAS, depending on the modifier. Although no final proof could be found, the most likely explanation is that this artifact is caused by a yet unidentified phosphorus species that causes a spectrally continuous absorption, which is corrected without problems by HR-CS AAS, but which is not recognized and corrected by the D2 BC system of LS AAS. 相似文献
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1000.
Alkyl-substituted insulin molecules are depository preparations used in the treatment of diabetes. The isolation and purification of these active compounds is performed on the hand of several complicated separation steps. In this work, nonmodified and new synthesized alpha,beta-unsaturated bovine insulins-(C12)(n) were selectively isolated from aqueous solution using tweezing adsorptive bubble separation (TABS) with BSA, which enabled reversible binding with the unpolar side chains of bovine insulin and its derivates. The bovine insulin/serum albumin complex could be efficiently transferred into the foam phase at pH 8 with an enrichment factor of 2.6 and a recovery of 89.7%. Experiments with alkylated alpha,beta-unsaturated bovine insulins-(C12)(n) performed at pH 9 enriched even quantitatively the complex under equal experimental conditions, accompanied with an enrichment factor of 3.3. Additionally performed radio immunoassay tests revealed that the immunological activity of alpha,beta-unsaturated bovine insulins-(C12)(n) remained unchanged after foaming. 相似文献