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201.
Wenluan?ZhangEmail authorView authors OrcID profile Ngoc?A.?Nguyen Roy?Murray Jiyuan?Xin Michael?E.?Mackay 《Journal of nanoparticle research》2017,19(9):315
Our previous study presented up to 20% power conversion efficiency (PCE) enhancement of poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) solar cells under the Fe3O4 nanoparticles (NPs) self-assembly (SA) effect by spin coating. Fe3O4 NPs (about 11 nm hydrodynamic diameter) form a thin layer at the top interface of the light absorbing active layer, which results in the generation of PCBM rich region improving the charge transport (Zhang et al. Sol Energ Mat Sol C 160:126–133, 2017). In order to investigate the feasibility of this Fe3O4 NPs SA effect under large-scale production condition, a smooth rod was implemented to mimic roll-to-roll coating technique and yield active layers having about the same thickness as the spin-coated ones. Small angle neutron scattering and grazing incidence X-ray diffraction were employed finding out similar morphologies of the active layers by these two coating techniques. However, rod-coated solar cell’s PCE decreases with the addition of Fe3O4 NPs compared with the one without them. This is because PCBM rich region is not created at the top interface of the active layer due to the absence of Fe3O4 NPs, which is attributed to the weak convective flow and low diffusion rate. Moreover, in the rod-coated solar cells, the presence of Fe3O4 NPs causes decrease in P3HT crystallinity, thus the charge transport and the device performance. Our study confirms the role of spin coating in the Fe3O4 NPs SA effect and enables researchers to explore this finding in other polymer nanocomposite systems. 相似文献
202.
A. Chiasera C. Armellini S.N.B. Bhaktha A. Chiappini Y. Jestin M. Ferrari E. Moser A. Coppa V. Foglietti P.T. Huy K. Tran Ngoc G. Nunzi Conti S. Pelli G.C. Righini G. Speranza 《Journal of Non》2009,355(18-21):1176-1179
95.8SiO2–4.2HfO2 planar waveguide activated by 0.2 mol% Er and 0.2 mol% Yb was fabricated by multi-target rf-sputtering technique. The optical parameters were measured by an m-line apparatus operating at 543.5, 632.8, 1319 and 1542 nm. The waveguide compositions were investigated by energy dispersive spectroscopy. The waveguide exhibits a single propagation mode at 1.3 and 1.5 μm with an attenuation coefficient of 0.2 dB/cm at 1.5 μm. The emission of 4I13/2 → 4I15/2 transition of Er3+ ion, with a 42 nm bandwidth was observed upon TE0 mode excitation at 980 and 514.5 nm. Photoluminescence excitation spectroscopy was used to obtain information about the effective excitation efficiency of Er3+ ions by co-doping with Yb3+ ions. Channel waveguide in rib configuration were fabricated by wet etching process in the active film. 相似文献
203.
Thi Bang Tam Dao Kim Ngoc Pham Yi-Lung Cheng Sang Sub Kim Bach Thang Phan 《Current Applied Physics》2014,14(12):1707-1712
The as-deposited WO3 thin films were post-annealed at different temperatures (300 °C and 600 °C) in air to investigate a correlation between crystallinity and switching behavior of WO3 thin films. Associating the results of XRD, FTIR, XPS and FESEM measurements, the annealing-caused crystallinity change contributes to the variation of the switching behaviors of the WO3 thin films. The as-deposited WO3 films with low crystalline structure are preferred for random Ag conducting path, resulting in large switching ratio but fluctuating I–V hysteresis, whereas the annealed WO3 films with crystallized compact structure limits Ag conducting path, favoring the stable I–V hysteresis but small switching ratio. It is therefore concluded that electrochemical redox reaction-controlled resistance switching depends not only on electrode materials (inert and reactive electrodes) but also on crystallinity of host oxide. 相似文献
204.
In the present paper, we are interested in the propagation of Rayleigh waves in an isotropic elastic half-space coated with a thin isotropic elastic layer. The contact between the layer and the half space is assumed to be smooth. The main purpose of the paper is to establish an approximate secular equation of the wave. By using the effective boundary condition method, an approximate, yet highly accurate secular equation of fourth-order in terms of the dimensionless thickness of the layer is derived. From the secular equation obtained, an approximate formula of third-order for the velocity of Rayleigh waves is established. The approximate secular equation and the formula for the velocity obtained in this paper are potentially useful in many practical applications. 相似文献
205.
Dawn A Shiraki T Ichikawa H Takada A Takahashi Y Tsuchiya Y Lien le TN Shinkai S 《Journal of the American Chemical Society》2012,134(4):2161-2171
Self-assembly behaviors of a series of systems (G1, G2, and G3) possessing same organic building blocks based on a substituted anthracene have been investigated in decalin. G2 and G3 are dominated by head-to-tail (ht) and head-to-head (hh) type dimers of G1, respectively. G1 gives a thermoresponsive gel that behaves ideally, showing frequency-independent elastic and viscous moduli. Interestingly, G2 produces a thixotropic gel that shows the signature of structural relaxation, signifying the dynamic nature of the system. In contrast, G3 remains fluidlike. As investigated by scanning electron microscopy (SEM), in the assembly process of G2, first disklike nanoaggregates are formed, and in the second step these aggregates interact to construct the densely packed secondary assembly. A transition from secondary assembly to primary assembly under shear initiates the mechanoresponsive destruction of the gel. In the self-assembly process, G1 propagates in a one-dimensional fashion, whereas G2 and G3 can propagate in a two-dimensionional fashion. The same side orientation of the substituents in G3 facilitates the formation of a compact closed-shell-type structure, which results in the generation of isolated nanocrystals. The long-range weak interaction together with the capability of propagating in two dimensions is found to be essential for the construction of such a mechanoresponsive assembly. C(60) and C(70) could be incorporated successfully in G2 assembly to develop mechanoresponsive fullerene assemblies. The presence of fullerenes not only enhances the elastic properties of G2 but also intensifies the thixotropy. C(70) appears to be a superior guest in terms of property enhancement due to its better size fitting with the concave-shaped host. 相似文献
206.
T Noguchi T Shiraki A Dawn Y Tsuchiya le TN Lien T Yamamoto S Shinkai 《Chemical communications (Cambridge, England)》2012,48(65):8090-8092
Nonlinear fluorescence response, which is particularly important to attain the high signal-to-background ratio, was realized by the aggregation-induced fluorescence increase of guanidinium-tethered tetraphenylethene with ATP. 相似文献
207.
MC Galan AT Tran K Bromfield S Rabbani B Ernst 《Organic & biomolecular chemistry》2012,10(35):7091-7097
A new N-benzenesulfonyl-based ionic-liquid mass spectroscopy label (I-Tag2) for covalent attachment to substrates has been prepared. I-Tag2 was used to monitor oligosaccharide elongation and serve as a purification handle. Starting from chemically synthesized I-Tag2-labelled N-acetyl glucosamine (GlcNAc) 1, I-Tag2-LacNAc (Galβ(1-4)GlcNAc) 2 and I-Tag2-Lewis(X) (Galβ(1-4)[Fucα(1-3)]GlcNAc) 3, which are oligosaccharides of biological relevance, were enzymatically prepared. The apparent kinetic parameters for the enzyme catalysed transformations with β-1,4-galactosyltransferase (β-1,4-GalT) and fucosyltransferase VI (FucT VI) were measured by LC-MS demonstrating the applicability and versatility of the new I-Tags in enzymatic transformations with glycosyltransferases. 相似文献
208.
Hoang Ngoc Tuan 《Journal of Optimization Theory and Applications》2012,154(3):904-915
We obtain sufficient conditions for the linear convergence of the iterative sequences produced by the Pham Dinh–Le Thi algorithm
for the trust-region subproblem. In addition, we give two examples to show that, if the sufficient conditions are not satisfied,
then the sequences may not be linearly convergent. 相似文献
209.
Shinya Maenosono JaeDong Lee Anh Thi Ngoc Dao Derrick Mott 《Surface and interface analysis : SIA》2012,44(13):1611-1614
This article reports on the peak shape analysis of X‐ray photoelectron spectra of gold‐silver core‐shell (Au@Ag) nanoparticles (NPs) using an asymmetric Gaussian–Lorentzian mixed function. Unlike Ag NPs, Au@Ag NPs have no oxide peak and show asymmetric line shape with a high energy tail in Ag 3d core‐level spectra. A monotonic increase in the Ag 3d binding energy and a decrease in the degree of asymmetry with increasing the Ag shell thickness were observed supporting the occurrence of charge transfer from Au core to Ag shell. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
210.
Hoang Ngoc Long 《Physics of Atomic Nuclei》2001,64(1):103-106
Within the minimal SU(3)C ? SU(3)L ? U(1)N model, the lepton-flavor-violating decay π+→μ?νμ e + e + is calculated without directly invoking lepton mixing. The branching ratio for this rare pion-decay mode is found to be much smaller than the current experimental upper limit. If the anomalous interactions are discarded, this result coincides with the result of the previous calculation. 相似文献