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91.
Cheng Gu Teng Fei Ming Zhang Chuannan Li Dan Lu Yuguang Ma 《Electrochemistry communications》2010,12(4):553-556
The electrochemical polymerization (EP) method to fabricate highly luminescent films and devices is rarely reported. It is typically believed that the organic light-emitting devices (OLEDs) made by EP method behave low performance because of the structural defects, doped electrolytes, and rough morphology in EP films. Here we present a new strategy to fabricate high-quality EP films including the special molecular design for EP precursors and the electrochemical control for EP processes. The resulting EP films exhibit high fluorescence, low doping levels, and smooth surface morphology. The efficiency of EP film devices arrive a level of >10 cd A?1 (green-emission). Moreover, the full-color micropatterned EP films with sharp edge and high resolution have been achieved, demonstrating a new simple method for fabricating micropatterned luminescent polymers and devices compared with currently used techniques. 相似文献
92.
Jizhen Liu Musi Ji Zhidong Li Xun Xu Lili Li Huawen Li Yuguang Tian Xiaohua Su 《Biomedical chromatography : BMC》2020,34(11):e4937
A simple and sensitive ultra-high performance liquid chromatography–tandem mass spectrometric (UHPLC–MS/MS) method was developed and validated for the determination of ARQ531, a Bruton’s tyrosine kinase inhibitor in rat plasma. After protein precipitation with acetonitrile, the samples were separated on a UPLC BEH C18 column with 0.1% formic acid in water and acetonitrile as mobile phase at a flow rate of 0.4 ml/min. The mass detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring with precursor-to-product ion transitions of m/z 479.1 > 365.1 and m/z 441.2 > 138.1 for ARQ531 and internal standard, respectively. Good linearity (correlation coefficient > 0.9988) was achieved over the concentration range of 0.5–1,000 ng/ml and the lower limit of quantitation was 0.5 ng/ml. The accuracy ranged from −13.50 to 11.35% and the precision was <8.87%. The extraction recovery was >85.56%. ARQ531 was demonstrated to be stable under the tested conditions. The validated method was further applied to a pharmacokinetic study of ARQ531 in rats after intravenous (1 mg/kg) and oral (1, 3 and 10 mg/kg) administration. The results demonstrated that ARQ531 displayed linear pharmacokinetic profiles over the oral dose range of 1–10 mg/kg and good oral bioavailability (>50%). 相似文献
93.
A method of determination of 32 carbonyl compounds by high performance liquid chromatography (HPLC) and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) after derivatization with 2,4-dinitrophenylhydrazine (DNPH) was developed and successfully applied to the atmosphere sample of a residential area of Liwan District (S1) and a research institute of Tianhe District (S2) in Guangzhou, China. Some operation conditions of ESI-MS/MS in the negative ion mode including selection of parent and daughter ions, declustering potential (DP), entrance potential (EP), collision energy (CE), collision cell exit potential (CXP) and effect of buffer in ESI-MS/MS process were optimized. The regression coefficient of the calibration curves (R2), recovery, reproducibility (R.S.D., n = 5) and limit of detection (LOD) were in the range of 0.9938-0.9999, 90-104%, 1.7-11% and 0.4-9.4 ng/m3, respectively. Among most of the samples, acetone was the most abundant carbonyl in two sampling sites and formaldehyde, acetaldehyde and butyraldehyde/2-butanone were also abundant carbonyls. In contrast to LC-UV method, the LOD, the separation of some co-eluting compounds and the precision (mainly to higher molecular weight carbonyls) are all improved by LC-ESI-MS/MS. 相似文献
94.
从润湿热研究HZSM-5分子筛与不同液体相互作用的特点 总被引:1,自引:0,他引:1
ZSM-5是一类新型分子筛,共物理化学性能的研究引起了广泛的兴趣。本工作测定了高温脱气的HZSM-5分子筛在正己烷、正庚烷,正癸烷、正十二烷,环己烷、苯、甲苯,邻、间、对二甲苯,甲醇和乙醇中的润湿热。 相似文献
95.
96.
Yuguang ZHANG 《数学年刊B辑(英文版)》2007,28(4)
Compact K(a)hler manifolds with semi-positive Ricci curvature have been investigated by various authors. From Peternell's work, if M is a compact K(a)hler n-manifold with semi-positive Ricci curvature and finite fundamental group, then the universal cover has a decomposition (M) ≌ X1 × … × Xm, where Xj is a Calabi-Yau manifold, or a hyperK(a)hler manifold, or Xj satisfies Ho(Xj,Ωp) = 0. The purpose of this paper is to generalize this theorem to almost non-negative Ricci curvature K(a)hler manifolds by using the Gromov-Hausdorff convergence. Let M be a compact complex n-manifold with non-vanishing Euler number. If for any ε > 0, there exists a K(a)hler structure (Je,ge) on M such that the volume Volge(M) < V, the sectional curvature |K(gε)| < Λ2, and the Ricci-tensor Ric(gε)> -εgε, where ∨ and Λ are two constants independent of ε. Then the fundamental group of M is finite, and M is diffeomorphic to a complex manifold X such that the universal covering of X has a decomposition, (X) ≌ X1 × … × Xs, where Xi is a Calabi-Yau manifold, or a hyperK(a)hler manifold, or Xi satisfies Ho(Xi, Ωp) = {0}, p > 0. 相似文献
97.
98.
In this paper, a topological intersection theorem of a family of sets with H-convex sections is established. As an application to this theorem, the Nash equilibrium of abstract economy, the Ky-Fan minimax theorem, and an existence problem of solution for quasi-variational inequality are studied. The results presented in this paper modify and extend the corresponding results given in the literature.AMS Subject Classification (2000) 47H10This work is supported by the Foundation of Yunnan Science Technology Commission, China. 相似文献
99.
Yuguang Fan 《Journal of Theoretical Probability》2017,30(2):675-699
For nonnegative integers r, s, let \(^{(r,s)}X_t\) be the Lévy process \(X_t\) with the r largest positive jumps and the s smallest negative jumps up till time t deleted, and let \(^{(r)}\widetilde{X}_t\) be \(X_t\) with the r largest jumps in modulus up till time t deleted. Let \(a_t \in \mathbb {R}\) and \(b_t>0\) be non-stochastic functions in t. We show that the tightness of \(({}^{(r,s)}X_t - a_t)/b_t\) or \(({}^{(r)}{\widetilde{X}}_t - a_t)/b_t\) as \(t\downarrow 0\) implies the tightness of all normed ordered jumps, and hence the tightness of the untrimmed process \((X_t -a_t)/b_t\) at 0. We use this to deduce that the trimmed process \(({}^{(r,s)}X_t - a_t)/b_t\) or \(({}^{(r)}{\widetilde{X}}_t - a_t)/b_t\) converges to N(0, 1) or to a degenerate distribution as \(t\downarrow 0\) if and only if \((X_t-a_t)/b_t \) converges to N(0, 1) or to the same degenerate distribution, as \(t \downarrow 0\). 相似文献
100.
Baoling Wang Fangzhong Shen Ping Lu Shi Tang Wu Zhang Shiwei Pan Meirong Liu Linlin Liu Song Qiu Yuguang Ma 《Journal of polymer science. Part A, Polymer chemistry》2008,46(9):3120-3127
This article describes the synthesis and characterization of a new ladder‐type poly (p‐phenylene) (LPFC) containing alkylcarbazole and dialkylfluorene units in backbone, and its optical and electrochemical properties as well as its light‐emitting device performance. LPFC shows the well‐defined structure, high molecular weights, excellent thermal stability, and good solubility in common organic solvents. And it also shows strongly blue emission (λmax = 465 nm) with quantum efficiency of 70% in solution, while its solid emission (λmax = 470 nm) is almost the same as its solution. Electrochemical studies show that the highest occupied molecular orbital (HOMO) energy levels of LPFC is up to 5.29 eV, which is significantly higher than that of LPPP without carbazole in backbone, indicating an enhanced ability of hole injection from anodes. Furthermore, the single layer light‐emitting device using LPFC as the active layer shows blue emission (λmax = 470 nm) with maximum luminescence of ~ 2000 cd/m2 and maximum luminance efficiency of 0.43 cd/A. The attractive properties exhibited from new ladder‐type polymer establish LPFC as a good candidate for the potential application as transporting and emitting layer in polymeric light emitting diodes. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3120–3127, 2008 相似文献