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991.
A PROBABILITY AND INTERVAL HYBRID STRUCTURAL RELIABILITY ANALYSIS METHOD CONSIDERING PARAMETERS’ CORRELATION 总被引:1,自引:0,他引:1
提出了一种考虑相关性的概率-区间混合不确定性模型及结构可靠性分析方法,能够处理变量之间具有相关性的混合可靠性分析问题. 分别针对概率变量,概率区间变量及区间变量定义了相关角的概念,用以定量描述变量之间的相关性;通过仿射坐标,将相关变量转换为独立变量;给出了其可靠性分析模型,并构建了一高效求解方法获得其可靠性指标和失效概率区间;最后通过分析两个数值算例,验证了方法的有效性. 相似文献
992.
Brightening single-photon emitters by combining an ultrathin metallic antenna and a silicon quasi-BIC antenna
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Bright single-photon emitters(SPEs)are fundamental components in many quantum applications.However,it is difficult to simultaneously get large Purcell enhancements and quantum yields in metallic nanostructures because of the huge losses in the metallic nanostructures.Herein,we propose to combine an ultrathin metallic bowtie antenna with a silicon antenna above a metallic substrate to simultaneously get large Purcell enhancements,quantum yields,and collection efficiencies.As a result,the brightness of SPEs in the hybrid nanostructure is greatly increased.Due to the deep subwavelength field confinement(mode size<10 nm)of surface plasmons in the ultrathin metallic film(thickness<4 nm),the Purcell enhancement of the metallic bowtie antenna improves by more than 25 times when the metal thickness decreases from 20 nm to 2 nm.In the hybrid nanostructures by combining an ultrathin metallic bowtie antenna with a silicon antenna,the Purcell enhancement(Fp≈2.6×106)in the hybrid nanostructures is 63 times greater than those(≤4.1×104)in the previous metallic and hybrid nanostructures.Because of the reduced ratio of electromagnetic fields in the ultrathin metallic bowtie antenna when the high-index silicon antenna is under the quasi-BIC state,a high quantum yield(QY≈0.70)is obtained.Moreover,the good radiation directivity of the quasi-BIC(bound state in the continuum)mode of the silicon antenna and the reflection of the metallic substrate result in a high collection efficiency(CE≈0.71).Consequently,the overall enhancement factor of brightness of a SPE in the hybrid nanostructure is EF?≈Fp×QY×CE≈1.3×106,which is 5.6×102 times greater than those(EF?≤2.2×103)in the previous metallic and hybrid nanostructures. 相似文献
993.
GengGeng Luo DongLiang Wu Li Liu DongXu Li QingHua Zhao ZiJing Xiao JingCao Dai 《中国科学:化学(英文版)》2012,55(7):1213-1219
An octameric water moiety which consists of a chairlike water hexamer and two pendent water molecules in the 1,4-diaxial positions and shows a similar structure to the hydrocarbon(1r,4r)-1,4-dimethylcyclohexane,is unambiguously trapped in a2D Cu(Ⅱ) mixed-ligand coordination polymer,{[Cu2(bpp)2(H2O)2(bpda)2 ].6H2O} n(1)(bpp = 1,3-bis(4-pyridyl)propane and H2 bpda =2,2’-biphenyldicarboxylic acid).The water octamer can be extended into a hybrid carboxylate-water decamer when carboxylic oxygen atoms from bpda2 are involved.Interestingly,the present hybrid decamer bears a similar structural topology to a butterfly(H2O) 10 cluster.The reversible dehydration/hydration of 1 is determined by X-ray powder diffraction studies. 相似文献
994.
995.
Two novel and well-defined polyhedral oligomeric silsesquioxanes(POSS) with two same Si8O12 cores and a reactive NH group, namely bridged-POSS(2a and 2b),have been prepared by the traditional ’corner-capping’ reaction.X-ray diffraction demonstrates that those two POSS have the similar T8 structure.From the thermo-gravimetric analysis,bridged-POSS shows the belter thermal degradation stability than the contrastive POSS. 相似文献
996.
997.
998.
Au‐Fe3O4 nanoparticles were widely used as nanoplatforms for biologic applications through readily further functionalization. Dopamine (DA)‐coated superparamagnetic iron oxide (SPIO) nanoparticles (DA@Fe3O4) have been successfully synthesized using a one‐step process by modified coprecipitation method. Then 2–3 nm gold nanoparticles were easily conjugated to DA@Fe3O4 nanoparticles by the electrostatic force between gold nanoparticles and amino groups of dopamine to afford water‐soluble Au‐Fe3O4 hybrid nanoparticles. A detailed investigation by dynamic light scatting (DLS), transmission electron microscopy (TEM), fourier transform infrared (FT‐IR) and X‐ray diffraction (XRD) were performed in order to characterize the physicochemical properties of the hybrid nanoparticles. The hybrid nanoparticles were easily functionalized with a targeted small peptide A54 (AGKGTPSLETTP) and fluorescence probe fluorescein isothiocyanate (FITC) for liver cancer cell BEL‐7402 imaging. This simple approach to prepare hybrid nanoparticles provides a facile nanoplatform for muti‐functional derivations and may be extended to the immobilization of other metals or bimolecular on SPIO surface. 相似文献
999.
D Kiriya R Kawano H Onoe S Takeuchi 《Angewandte Chemie (International ed. in English)》2012,51(32):7942-7947
A matter of orientation: The nanofibers in cables that consist of assemblies of these nanofibers can be oriented parallel or perpendicular to the longitudinal axis by regulating the fluidic velocities of the core and sheath flows in coaxial microfluidic devices. Control of the internal morphology enables fabrication of cables with improved electrical conductivity and mechanical properties. 相似文献
1000.
Hybrid biomaterials are systems created from components of at least two distinct classes of molecules, for example, synthetic macromolecules and proteins or peptide domains. The synergistic combination of two types of structures may produce new materials that possess unprecedented levels of structural organization and novel properties. This Review focuses on biorecognition-driven self-assembly of hybrid macromolecules into functional hydrogel biomaterials. First, basic rules that govern the secondary structure of peptides are discussed, and then approaches to the specific design of hybrid systems with tailor-made properties are evaluated, followed by a discussion on the similarity of design principles of biomaterials and macromolecular therapeutics. Finally, the future of the field is briefly outlined. 相似文献