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91.
The convergent total synthesis of the HIF-1 inhibitor laurenditerpenol 1a is reported. The key step is the Julia olefination-reduction process between the two components, the sulfone 4 (prepared from the dimethylfuran-maleic anhydride Diels-Alder adduct) and the aldehyde 3 (prepared from 3-methylcyclohexenone).  相似文献   
92.
A systematic overview on the characteristics of super heavy nuclei from Z = 101 to Z = 130 based on the data by P. Moller et al. is presented. The nuclei which have the biggest mean binding energy in each of their isotope chain show systematic regular behavior, indicating that the mean binding energy is a good criterion to classify super heavy nuclei by their stabilities. Further investigation on the nuclear data at and after Z=127 has been suggested.  相似文献   
93.
Fringe element reconstruction technique for tracking the free surface in three‐dimensional incompressible flow analysis was developed. The flow field was calculated by the mixed formulation based on a four‐node tetrahedral element with a bubble function at the centroid (P1+/P1). Since an Eulerian approach was employed in this study, the flow front interface was advected by the flow through a fixed mesh. For accurate modelling of interfacial movement, a fringe element reconstruction method developed can provide not only an accurate treatment of material discontinuity but also surface tension across the interface. The effect of surface tension was modelled by imposing tensile stress directly on the constructed surface elements at the flow front interface. To verify the numerical approach developed, the developed algorithm was applied to two examples whose solutions are available in references. Good agreement was obtained between the simulation results and these solutions. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
94.
Sb-doped silica EDF showed an opposite temperature dependent gain profile compared to Al-doped silica EDF. Concatenation of those two EDFs showed a gain variation less than ± 0.4 dB over 40nm of C-band with the 15dB gain, in the temperature range of - 40 to + 80℃.  相似文献   
95.
Highly luminescent, rhabdophane (Ce(0.33)La(0.66))PO4.nH2O nanorods and nanoparticles were prepared in aqueous solutions by ultrasonication, at pH 1 and pH 12, respectively. Both nanorods (5 to 9 nm wide and several tens to several hundreds nm long) and nanoparticles (elongated, connected 5 nm particles) were as small and as uniform as products obtained from methods that utilize complexing agents or surfactants, only with no complexing agent. This method of synthesis by ultrasonication is a fast and simple method and it is expected to be applicable for the synthesis of other nanocrystalline lanthanide phosphates.  相似文献   
96.
电容去离子(CDI)技术是一种新型的海水淡化技术,因其具有环境友好、操作简单和能耗低等优势而受到广大研究者的关注。在CDI技术中,电吸附的性能与装置的构型有着密切的联系。本文综述了目前常见的几种CDI装置,包括膜电容去离子(MCDI)、流动电极电容去离子(FCDI)、杂化电极电容去离子(HCDI)、反式电极电容去离子(i-CDI)以及脱盐电池(DB),对这几种装置的发展历程和装置构型进行介绍,最后,对CDI的装置构型在未来的研究发展方向进行了展望,以期为CDI装置在电脱盐领域的研究和应用提供参考。  相似文献   
97.
We report a universal scaling behavior of the first arrival time of a traveling magnetic domain wall into a finite space-time observation window of a magneto-optical microscope enabling direct visualization of a Barkhausen avalanche in real time. The first arrival time of the traveling magnetic domain wall exhibits a nontrivial fluctuation and its statistical distribution is described by universal power-law scaling with scaling exponents of 1.34+/-0.07 for CoCr and CoCrPt films, despite their quite different domain evolution patterns. Numerical simulation of the first arrival time with an assumption that the magnetic domain wall traveled as a random walker well matches our experimentally observed scaling behavior, providing an experimental support for the random-walking model of traveling magnetic domain walls.  相似文献   
98.
Click‐active surfaces patterned at 200 nm resolution are demonstrated using the dual functional polymeric film, poly(propargyl methacrylate) (PPMA). The commercially available monomer of propargyl methacrylate (PMA) is polymerized in a single step by initiated chemical vapor deposition (iCVD). FT‐IR and X‐ray photoelectron spectroscopy confirm retention of the click‐active acetylene functional group in the bulk and surface of the iCVD film, respectively. Treating substrates with silane coupling agents prior to deposition results in grafting of iCVD PPMA polymers onto various inorganic surfaces. This grafting technique provides the chemical and mechanical stability required for the PPMA layer to survive the subsequent wet chemical steps used for click functionalization. Successful attachment of an azido‐functionalized coumarin dye is demonstrated. Moreover, the PPMA film displays direct positive‐tone sensitivity to e‐beam irradiation, which enables e‐beam patterning without the use of a resist layer. Direct e‐beam exposure of the multifunctional PPMA iCVD layer results in a 200 nm pattern to which quantum dot nanoparticles are selectively conjugated on the substrates by click chemistry.

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99.
用于NH3选择性催化还原NO的非钒基催化剂研究进展   总被引:4,自引:0,他引:4  
NH3选择性催化还原NO (NH3-SCR)技术在燃煤电厂烟气脱硝过程中有着多年的工业应用经验,也是最有望实际应用于柴油车尾气NOx催化去除的技术之一.鉴于目前工业化应用的V2O5-WO3 (MoO3)/TiO2催化剂体系应用于柴油车尾气净化仍存在着诸多问题,开发新型、高效、稳定且环境友好的非钒基NH3-SCR催化剂体...  相似文献   
100.
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