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71.
Jing Sui Lijuan Zhang Jadranka Travas-Sejdic Paul A. Kilmartin 《Macromolecular Symposia》2010,290(1):107-114
Summary: Hollow microspheres of PEDOT (poly(3,4-ethylenedioxythiophene) ranging from 0.5 to 10 µm have been synthesized by chemically oxidative polymerization of EDOT(3,4-ethylenedioxythiophene) using ammonium persulfate in a catanionic surfactant solution obtained by mixing cetyltrimethylammonium bromide (CTAB) and sodium dodecylbenzenesulfonate (SDBS). The effect of the molar ratio of CTAB to SDBS on the morphology of the PEDOT oxidation products has been investigated using SEM and TEM and by an analysis of the structural properties using UV-visible, FTIR and Raman spectroscopies, elemental analysis and conductivity measurements. The electro-catalytic activity of PEDOT hollow microspheres for the oxidation of ascorbic acid was investigated by cyclic voltammetry in a pH 6 citrate/phosphate buffer solution and compared to the activity of granular PEDOT particles formed in the absence of the catanionic surfactant. 相似文献
72.
Yang Xiang Bo Zhou Xianjie Wang Yu Sui Zhe Lü 《Journal of magnetism and magnetic materials》2009,321(9):1188-1191
Mn4+-rich perovskite manganites (nominal composition: Pr0.1Ca0.9MnO3) were synthesized by using a citric acid method and sintered at different temperatures (800, 900, 1000, and 1300 °C) to adjust the concentration of charge carrier. All the samples are found to be in the cluster glass state at low temperature, as indicated by dc and ac magnetization. With the increase of sintering temperature, the ferromagnetic component in samples increases at first, and attains a maximum at 1000 °C, then decreases again at 1300 °C, which could be well interpreted by the change of charge carrier concentration induced by nonstoichiometry, consistent with the trend on the phase diagram. However, nonstoichiometry breaks long-range Mn-O-Mn interaction, resulting in the variance from the phase diagram. 相似文献
73.
IntroductionThechemistryoforganoaluminum,organogalliumandorganoindiumcomplexeshasattractedmuchat'tentionduenotonlytotheirinterestingstructuralandchemicalpropertiesbutalsotheirapplicationinsemiconductormaterialsl-5.InthecourseofourstudiesonexploringvolatileMOCVDprecursorsthathavethepropertiesoflowertoxicityandhigherstability,wehaverecentlyreportedonthesynthesisandcharacterizationofintermolecularadducts'-',novelbondingmodecomplexes",',andthecomplexesinwhichN/Omixed-donorcrownethersasligands'l'… 相似文献
74.
The compatible carbon-silicon complex materials originated from precursor diglycerylsilane (DGS) and sugar-modified silane
N-(3-triethoxysilylpropyl)gluconamide (GLS) have gained substantial popularity by demonstrating admirable properties to stabilize
entrapped biomolecules. The microenvironment inside these materials, especially the distribution of sugar moieties inside
the matrix, which is likely the most critical factor determining compatibility of these materials, still remains unclear.
To deeply investigate the biocompatibility mechanism of these materials, we have adopted two different preparation routes
for these materials by introducing GLS into the starting DGS sol stage, but things are different after the DGS gel is formed.
A fluorescence probe rhodamine 6G is introduced herein in the DGS sol to monitor the distribution of GLS moieties, as well
as the evolution of the microenvironment inside resulting materials. All in all, the findings demonstrated that the timing
of GLS addition plays a critical role in controlling the evolution of the inner structure of materials, suggesting that this
factor provides a promising route to tune the properties of the resulting materials.
Supported by the National Natural Science Foundation of China (Grant No. 20876176), Scientific Research Foundation for the
Returned Overseas Chinese Scholars by the State Education Ministry, Key Project of Chinese Ministry of Education (Grant No.
109100), Doctoral Project of Shandong Province (Grant No. 2008BS09013), Research Foundation of Key Laboratory of Carbon Materials,
Institute of Coal Chemistry, CAS (Grant No. KFJJ0506), and Natural Science Foundation of Shandong Province (Grant No. Q2007B02) 相似文献
75.
76.
A variational approach is employed for obtaining zero-free solutions of a nonlinear eigenvalue problem that appears in several recent studies. Our proofs are elementary but our results are sharp and yield corrections to several existing assertions in the literature. 相似文献
77.
In order to realize efficient automatic packaging of the waveguide chip and reduce its cost, an integrated optic waveguide chip packaging system based on center-integration algorithms is designed and fabricated, which realizes 11-dimension position adjustment and fewer operation times. The integration center position is obtained through the sampling data. The system can avoid local optimum and reduce packaging time as well as packaging loss. The automated alignment of a single-core fiber with channel waveguide and single-core fiber system is completed in less than 2 min. The packaging experiment of a single-core fiber array with 1 × 8 splitter coupler and 8-core fiber array is completed in less than 5 min with an insert-loss of less than 10.5 dB and homogenization of less than 0.4 dB. The system is validated with good efficiency and practicability. 相似文献
78.
79.
80.
In this paper, a false color image fusion method for merging visible and infrared images is proposed. Firstly, the source images and reference image are decomposed respectively by Laplacian pyramid transform. Then the grayscale fused image and the difference images between the normalized source images are assigned to construct YCBCR components. In the color transfer step, all the three channels of the color space in each decomposition level are processed with the statistic color mapping according to the color characteristics of the corresponding sub-images of the reference image. Color transfer is designed based on the multi-resolution scheme in order to significantly improve the detailed information of the final image, and to reduce excessive saturation phenomenon to have a comparatively natural color appearance compared with the classical global-coloring algorithm. Moreover, the differencing operation between the normalized source images not only provides inter-sensor contrast to make popping the potential targets but also weakens the influence of the ambient illumination variety to a certain degree. Finally, the fused results and several metrics for evaluation of fused images subjectively and objectively illustrate that the proposed color image fusion algorithm can yield a more complete mental representation of the perceived scene, resulting in better situational awareness. 相似文献