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971.
972.
Tsyr‐Yuan Hwu Sourav Basu Ruey‐Min Chen Yen‐Ju Cheng Jui‐Hung Hsu Wunshain Fann Tien‐Yau Luh 《Journal of polymer science. Part A, Polymer chemistry》2003,41(14):2218-2231
A range of silanylene‐spaced divinylbenzene copolymers ( 1 ) and the corresponding monomers ( 2 ) have been synthesized by the rhodium‐catalyzed hydrosilylation of the corresponding bisalkynes with bissilyl hydrides, and the photophysical properties of 1 and 2 have been investigated. The silicon moiety in 1 serves as an insulating tetrahedral spacer that makes 1 highly folded. The two chromophores may be in close proximity such that a ground‐state intrachain interaction between two conjugated moieties through space might occur. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2218–2231, 2003 相似文献
973.
Sheng‐Han Wu Jar‐Hung Chen Chi‐Hsien Shen Chia‐Chen Hsu Raymond Chien‐Chao Tsiang 《Journal of polymer science. Part A, Polymer chemistry》2004,42(23):6061-6070
To study the effect of nonconjugation on polymeric and photophysical properties of thiophene‐containing polymers, new light‐emitting copolymers comprising either alternate 2,5‐diphenylthiophene and vinylene or alternate 2,5‐diphenylthiophene and aliphatic ether segments were synthesized. Both copolymers contained 2,5‐diphenylthiophene as the major chromophore and emitted a sky bluish fluorescence in dilute solution (10?2 mg/mL). With a rigid and planarity structure and the concomitant crystallinity, the former copolymer (fully conjugated) possessed a higher quantum efficiency, a higher glass‐transition temperature, and a better thermal stability. In contrast, the latter copolymer (conjugated–nonconjugated) had better solubility and provided enhanced photophysical properties for the fabricated polymeric light‐emitting diode (PLED) device: at 15 V, the maximum current and brightness were 110 mA/cm2 and 4289 cd/m2, respectively, and the electroluminescence efficiency remained constant at approximately 4.9 cd/A in a voltage range of 8 to 14 V. The existence of intramolecular/intermolecular aggregates in the latter copolymer was corroborated from the the UV–vis and photoluminescence spectra of its solutions. With an increase in solution concentration, the shape and λmax of the photoluminescence spectrum were redshifted. In a solution with a concentration as high as 10 mg/mL, the redshift was so drastic that the photoluminescence spectrum was nearly identical to that of a solid‐film. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6061–6070, 2004 相似文献
974.
975.
Highly Efficient Dye‐Sensitized Solar Cells Based on Panchromatic Ruthenium Sensitizers with Quinolinylbipyridine Anchors
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Hsiu‐Hsuan Yeh Hsin‐Pei Wu Yun Chi John N. Clifford Emilio Palomares Shih‐Hung Liu Pi‐Tai Chou Gene‐Hsiang Lee 《Angewandte Chemie (International ed. in English)》2014,53(1):178-183
Panchromatic RuII sensitizers TF‐30–TF‐33 bearing a new class of 6‐quinolin‐8‐yl‐2,2′‐bipyridine anchor were synthesized and tested under AM1.5 G simulated solar irradiation. Their increased π conjugation relative to that of the traditional 2,2′:6′,2′′‐terpyridine‐based anchor led to a remarkable improvement in absorptivity across the whole UV–Vis–NIR spectral regime. Furthermore, the introduction of a bulky tert‐butyl substituent on the quinolinyl fragment not only led to an increase in the JSC value owing to the suppression of dye aggregation, but remarkably also resulted in no loss in VOC in comparison with the reference sensitizer containing a tricarboxyterpyridine anchor. The champion sensitizer in DSC devices was found to be TF‐32 with a performance of JSC=19.2 mA cm?2, VOC=740 mV, FF=0.72, and η=10.19 %. This 6‐quinolin‐8‐yl‐2,2′‐bipyridine anchor thus serves as a prototype for the next generation of RuII sensitizers with any tridentate ancillary. 相似文献
976.
Yat‐Ming So Dr. Guo‐Cang Wang Dr. Yang Li Dr. Herman H.‐Y. Sung Prof. Dr. Ian D. Williams Prof. Dr. Zhenyang Lin Prof. Dr. Wa‐Hung Leung 《Angewandte Chemie (International ed. in English)》2014,53(6):1626-1629
Whereas terminal oxo complexes of transition and actinide elements are well documented, analogous lanthanide complexes have not been reported to date. Herein, we report the synthesis and structure of a cerium(IV) oxo complex, [Ce?O(LOEt)2(H2O)]?MeC(O)NH2 ( 1 ; LOEt?=[Co(η5‐C5H5){P(O)(OEt)2}3]?), featuring a short Ce?O bond (1.857(3) Å). DFT calculations indicate that the hydrogen bond to cocrystallized acetamide plays a key role in stabilizing the Ce?O moiety of 1 in the solid state. Complex 1 exhibits oxidizing and nucleophilic reactivity. 相似文献
977.
Dr. Cheng‐Hsiu Chang Larry S. Lico Dr. Teng‐Yi Huang Dr. Shu‐Yi Lin Dr. Chi‐Liang Chang Prof. Dr. Susan D. Arco Prof. Dr. Shang‐Cheng Hung 《Angewandte Chemie (International ed. in English)》2014,53(37):9876-9879
Fondaparinux, a synthetic pentasaccharide based on the heparin antithrombin‐binding domain, is an approved clinical anticoagulant. Although it is a better and safer alternative to pharmaceutical heparins in many cases, its high cost, which results from the difficult and tedious synthesis, is a deterrent for its widespread use. The chemical synthesis of fondaparinux was achieved in an efficient and concise manner from commercially available D ‐glucosamine, diacetone α‐D ‐glucose, and penta‐O‐acetyl‐D ‐glucose. The method involves suitably functionalized building blocks that are readily accessible and employs shared intermediates and a series of one‐pot reactions that considerably reduce the synthetic effort and improve the yield. 相似文献
978.
Set-Valued and Variational Analysis - In this paper, we study bornological generalized differential properties of sets with nonsmooth boundaries, nonsmooth functions, and set-valued mappings in... 相似文献
979.
Emily C. Heider Khang Trieu Victor M. Diaz Karin Y. Chumbimuni-Torres Andres D. Campiglia Steven J. Duranceau 《Mikrochimica acta》2013,180(11-12):1013-1020
The modification of electrodes with gold nanoparticles results in an increased electrode surface area, enhanced mass transport, and improved catalytic properties. We have extended this approach to indium tin oxide (ITO) electrodes to obtain optically transparent gold nanorod-modified electrodes which display enhanced electrochemical capabilities and have the additional advantage of showing a tunable surface plasmon resonance. The procedures for attaining high surface coverage (15 gold nanorods per square µm) of such electrodes were optimized, and the potential-dependent surface plasmon resonance was studied under controlled electrical potential. In an exemplary sensor application, we demonstrate the detection of mercury via potential-dependent formation of an Au-Hg amalgam.
Immobilization of gold nanorods on optically transparent ITO electrodes provides tunable surface plasmon resonance detection coupled with electrochemical potential control. These novel sensors are applied to the detection and quantification of mercury with a combined SPR-electrochemical technique 相似文献
980.
Rodrigo Lopes F. de Oliveira Jorge H. Pedrobom Amauri A. Menegário Roberto N. Domingos Delcy A. Py Júnior Chang Hung Kiang 《Analytica chimica acta》2013
Acid mine drainage (AMD) is a serious environmental problem that creates acidic solution with high Mn concentrations. The speciation of residual Mn from AMD after an active treatment involving the addition of a neutralizing agent can reliably evaluate the treatment efficiency and provide knowledge of the Mn species being inputted into the environment. The aim of this study was to evaluate the in situ lability and speciation of Mn using the diffusive gradients in thin films (DGT) technique with treated drainage water from a uranium mine (TAMD). DGT devices with different binding phases (Chelex-100 and P81 and DE81membranes) were used to perform the in situ speciation of Mn. 相似文献