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151.
To identify and eliminate the inner filter effects (IFEs), prepositive and side cells containing absorbents are fixed beside
the fluorescer contained cell. In this way, excitation and emission lights can be quenched by primary and secondary outer
filter effects respectively, depending on absorbent concentration and cell length. Herein the quenching of emission fluorescence
caused by IFEs can be equally reduced by outer filter effects (OFEs) and the interference of IFEs was eliminated. This approach
was experimentally used for identifying the interaction mode and mechanism between BSA and nanoAg. Results showed that the
quenching of BSA fluorescence and synchronous fluorescence mainly attributes to IFEs, instead of static/dynamic fluorescent
quenching. In view of the above, the elimination of the interference of IFEs by the design of OFEs plays an important part
in the precise application of fluorescence detector. 相似文献
152.
153.
Wen-ting Xu Hai-ling Tu Da-li Liu Ran Teng Qing-hua Xiao Qing Chang 《Journal of nanoparticle research》2011,13(12):7095-7098
An innovative fabrication technique for the nanometer-sized SiGe/Si heterostructure was developed in this study. Ge was induced
in Si substrate by two-step ion implantation. The spherical SiGe nanoclusters are self-assembled in the Si substrate by subsequent
rapid thermal annealing at 1,100 °C. The diameter of the spherical SiGe nanoclusters is 5–7 nm. Visible photoluminescence
from this nanometer-sized SiGe/Si heterostructure at room temperature was investigated. We found three peak energies of visible
luminescence spectra at 1.97, 2.13, and 2.16 eV, respectively. The luminescence intensity depends on the number of the nanoclusters
and will be decreased because of the micro-defects around the heterostructure, which is discussed in detail. 相似文献
154.
Teng Wang Tianbo Liu Da-Xin Zhang Bo-Qiang Ma 《The European Physical Journal C - Particles and Fields》2011,71(9):1758
We investigate the rare decays \(B_{c} \rightarrow D_{s}(1968)\ell \overline{\ell}\) and \(B_{c}\rightarrow D_{s}^{*}(2317) \ell \overline{\ell}\) in the framework of the light-cone quark model (LCQM). The transition form factors are calculated in the space-like region and then analytically continued to the time-like region via exponential parametrization. The branching ratios and longitudinal lepton polarization asymmetries (LPAs) for the two decays are given and compared with each other. The results are helpful for investigating the structure of B c meson and for testing the unitarity of CKM quark mixing matrix. All these results can be tested in the future experiments at the LHC. 相似文献
155.
基于双材料微悬臂梁热变形原理的光学读出非制冷红外探测阵列经历了从有基底结构向无基底结构的发展过渡,无基底阵列的红外成像结果和有限元模型分析均表明无基底阵列不满足恒温基底条件.本文结合电学比拟的方法,提出了一种新的基于无基底焦平面阵列(focal plane Array,FPA)的热传递分析的理论模型.分析采用整体考虑的思路,避开了无基底FPA阵列各单元热传递互相影响所产生的复杂热分布分析,并考虑了框架对热量的吸收与传递.理论模型采用外边框与环境等温的边界条件,虽不及有限元方法对边界条件的处理灵活,但也已取
关键词:
光学读出
无基底
非制冷红外成像
焦平面阵列 相似文献
156.
Synchronization of complex community networks with nonidentical nodes and adaptive coupling strength
In this Letter, the complex dynamical networks with community structure and nonidentical nodes are considered. The globally asymptotical synchronization of the time-delayed complex community networks onto any uniformly smooth state is studied. Some simple and useful criteria are derived by constructing an effective control scheme and adjusting automatically the adaptive coupling strength. Finally, the developed techniques are applied to two complex community networks which are respectively synchronized to a chaotic trajectory and a periodic orbit, and numerical simulations are provided to show the feasibility of the developed methods. 相似文献
157.
SOME RESULTS ABOUT COVERING PROPERTIES OF PRODUCTS 总被引:3,自引:0,他引:3
SOME RESULTS ABOUT COVERING PROPERTIES OF PRODUCTS ¥JIANGJIGUANG;TENGHUIAbstract:Thefollowingresultsareproved:1.LetXbeascreen... 相似文献
158.
Chiral N-phosphonyl imine chemistry:asymmetric additions of glycine enolate to diphenyl diamine-based phosphonyl imines
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Diphenyl diamine-based phosphonyl imines attached by the N-isopropyl group in the auxiliary have been synthesized in good yields under convenient reaction conditions.These new chiral N-phosphonyl imines can react with glycine enolate smoothly to give chiral α-β diamino esters in good yields(72%-90%) and up to excellent diastereoselectivity(>99:1 dr).By treatment with HBr,the chiral auxiliary can be readily removed.The absolute structure has been unambiguously determined by converting a product to a known sa... 相似文献
159.
Ying Lin Zhi‐Kuan Chen Teng‐Ling Ye Yan‐Feng Dai Dong‐Ge Ma Zhun Ma Qin‐De Liu Yu Chen 《Journal of polymer science. Part A, Polymer chemistry》2010,48(2):292-301
A series of conjugated blue‐light‐emitting copolymers, PTC‐1 , PTC‐2 , and PTC‐3, comprised different ratios of electron‐withdrawing segments (spirobifluorene substituted with cyanophenyl groups) and electron‐donating segments (tricarbazole‐triphenylamines), has been synthesized. The structures of these polymers were characterized and their thermal, photophysical, electrochemical, and electroluminescence properties were measured. Incorporation of rigid spirobifluorene units into the copolymers led to blue‐shifted absorption peaks in dilute toluene solution. Cyclic voltammetric measurement indicated the bandgaps of the polymers were in the range of 2.77–2.94 eV. It was found that increasing cyanophenyl‐spirobifluorene content in the polymer backbone lowered both the HOMO and LUMO energy levels of the copolymers, which was beneficial for electron injection/transporting in the polymer layer of the device. OLED device evaluation indicated that all the polymers emitted sky blue to deep blue light when the pure polymers were used as the emissive layers in the devices with a configuration of ITO/PEDOT:PSS/polymers/CsF/Ca/Al. The devices have been optimized by doping 30 wt % PBD into the polymer layers. Among the doped devices, PTC‐2 showed the best performance with the turn‐on voltage of 3.0 V, maximum brightness of 7257 cd/m2, maximum current efficiency of 1.76 cd/A, and CIE coordinates of (0.15, 0.14). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 292–301, 2010 相似文献
160.