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991.
We report an axial-asymmetric high-Q Fabry-Perot cavity supporting nondegenerate Hermite-Gaussian modes of the same mode order. Axial asymmetry of mirror surface was introduced by mechanically grinding off one side of a cylindrical mirror substrate without degrading the original mirror quality. The bases of the resulting Hermite-Gaussian modes were aligned with respect to the direction of grinding, making it possible to prescribe the mirror principal axes. 相似文献
992.
993.
Vanecht E Binnemans K Seo JW Stappers L Fransaer J 《Physical chemistry chemical physics : PCCP》2011,13(30):13565-13571
The growth of gold nanoparticles (NPs) synthesized by sputter deposition on an ionic liquid surface is studied in situ in the bulk phase of the ionic liquids (ILs) 1-butyl-3-methylimidazolium dicyanamide [C(1)C(4)Im][N(CN)(2)], 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide [C(1)C(4)Im][Tf(2)N], 1-butyl-3-methylimidazolium tetrafluoroborate [C(1)C(4)Im][BF(4)], 1-butyl-3-methylimidazolium hexafluorophosphate [C(1)C(4)Im][PF(6)] and 1-butyl-3-methylimidazolium triflate [C(1)C(4)Im][TfO]. It is found that primary nanoparticles with a diameter smaller than 2.5 nm are present in the sample immediately after sputtering. Growth of these primary particles proceeds after the end of the sputtering process and stops when the nanoparticles reach a certain size. Depending on the viscosity of the ionic liquid this growth process can proceed several hours to several days. The growth speed is fastest for the least viscous ionic liquid and follows the trend [C(1)C(4)Im][N(CN)(2)] > [C(1)C(4)Im][Tf(2)N] > [C(1)C(4)Im][TfO] > [C(1)C(4)Im][BF(4)] > [C(1)C(4)Im][PF(6)]. It is also found that a higher concentration of sputtered gold results in faster growth of the gold nanoparticles. A discussion on the growth mechanism of sputtered gold NPs is included. 相似文献
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995.
996.
An efficient synthetic strategy for installation of the two vicinal quaternary carbon centers of the communesins is reported. Key steps include the O-allylation/Claisen rearrangement of spirolactone systems, which are formed by tandem intramolecular Heck cyclization/carbonylation. Substituent and solvent effects on the stereochemical outcome of the Claisen rearrangements have been examined. The stereochemical assignment of the allyl spirolactone previously reported as 17 has now been revised to 31, which has the communesin relative configuration at the quaternary carbons. Key C-allyl spirolactone 59 bearing functional handles required for the communesin core has been constructed with a 9.8:1 diastereomer ratio. 相似文献
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999.
Mi‐Ryung Park Jong‐Yi Park Deug‐Nam Kwon Ssang‐Goo Cho Chankyu Park Han‐Geuk Seo Yeoung‐Gyu Ko Sangiliyandi Gurunathan Jin‐Hoi Kim 《Electrophoresis》2013,34(4):493-500
Several biomarkers are routinely used clinically for predicting preterm labor; however, these factors are either nonspecific or detected too late. Here, we performed protein profiles in preterm‐ and term‐derived human umbilical cord by using 2DE. Approximately 200 different proteins were identified between preterm‐ and term‐delivered umbilical cords. Among them, 48 proteins were identified. A comparison of preterm proteome to that of term proteome revealed potential candidates for biomarkers, such as hypoxia‐inducible proteins, phosphorylated heat‐shock protein 27 (HSP27), transgelin, vimentin, and transferrin that are specific to preterm umbilical cords. Especially, HSP27 in preterm‐derived umbilical cords shows a significant increase in the mono‐ and tetra‐phosphorylation. The real importance of all of HSP27 phosphorylation as well as hypoxia‐inducible factor 1alpha, and glyceraldehyde 3‐phosphate dehydrogenase require further validation in vitro and in vivo; nevertheless, we believe that they could represent promising diagnostic targets for detection of sudden early delivery. In conclusion, the results of the current study may provide important insights into the molecular mechanisms underlying umbilical cord development. 相似文献
1000.
The measurement of residual d.c. in in-plane switching liquid crystal displays on a rubbed polyimide surface was investigated. We propose a new residual d.c. measurement method, named the ‘light minimum/maximum method’. The precision of residual d.c. measurement by the light minimum/maximum method was found to be greater than that of the conventional flicker minimizing method. 相似文献