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JPC – Journal of Planar Chromatography – Modern TLC - A new high-performance thin-layer chromatographic (HPTLC) method has been developed for the simultaneous estimation of... 相似文献
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Liang Wanjun Liu Zhengqing Li Dan Wu Xiaoping Liu Shaopu He Youqiu 《Mikrochimica acta》2015,182(1-2):297-306
Microchimica Acta - We describe a novel fluorescent bioprobe for the sensitive and selective detection of double-stranded DNA (dsDNA). It consists of quantum dots (Q-dots) whose fluorescence is... 相似文献
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One‐Pot Synthesis of Pomegranate‐Structured Fe3O4/Carbon Nanospheres‐Doped Graphene Aerogel for High‐Rate Lithium Ion Batteries 下载免费PDF全文
Dr. Dafang He Lixian Li Fengjuan Bai Chenyang Zha Prof. Liming Shen Prof. Harold H. Kung Prof. Ningzhong Bao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4454-4459
A unique hierarchically nanostructured composite of iron oxide/carbon (Fe3O4/C) nanospheres‐doped three‐dimensional (3D) graphene aerogel has been fabricated by a one‐pot hydrothermal strategy. In this novel nanostructured composite aerogel, uniform Fe3O4 nanocrystals (5–10 nm) are individually embedded in carbon nanospheres (ca. 50 nm) forming a pomegranate‐like structure. The carbon matrix suppresses the aggregation of Fe3O4 nanocrystals, avoids direct exposure of the encapsulated Fe3O4 to the electrolyte, and buffers the volume expansion. Meanwhile, the interconnected 3D graphene aerogel further serves to reinforce the structure of the Fe3O4/C nanospheres and enhances the electrical conductivity of the overall electrode. Therefore, the carbon matrix and the interconnected graphene network entrap the Fe3O4 nanocrystals such that their electrochemical function is retained even after fracture. This novel hierarchical aerogel structure delivers a long‐term stability of 634 mA h g?1 over 1000 cycles at a high current density of 6 A g?1 (7 C), and an excellent rate capability of 413 mA h g?1 at 10 A g?1 (11 C), thus exhibiting great potential as an anode composite structure for durable high‐rate lithium‐ion batteries. 相似文献
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Donor-acceptor type copolymers have wide applications in organic field-effect transistors and organic photovoltaic devices. Thieno[3,4-c]pyrrole-4,6-dione (TPD), as an electron-withdrawing unit, has been widely used in D-A type copolymers recently. Till now, the highest power conversion efficiency and mobility of TPD-based copolymers are over 8% and 1.0 cm2 V-1 s-1 respectively. In this review, the recent progress of TPD-based copolymers in organic solar cells and organic transistors is summarized. 相似文献
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Selective extraction of catecholamines by packed fiber solid‐phase using composite nanofibers composing of polymeric crown ether with polystyrene 下载免费PDF全文
Li‐Qin Chen Yu Wang Jian‐Song Qu Jian‐Jun Deng Xue‐Jun Kang 《Biomedical chromatography : BMC》2015,29(1):103-109
For the first time, electrospun composite nanofibers comprising polymeric crown ether with polystyrene (PCE‐PS) have been used for the selective extraction of catecholamines – dopamine (DA), norepinephrine (NE) and epinephrine (E) – prior to their analysis by high‐performance liquid chromatography–electrochemical detection. Using a minicartridge packed with PCE‐PS composite nanofibers, the target compounds were extracted effectively from urine samples to which diphenylborinic acid 2‐aminoethyl ester was added as a complexing reagent. The extracted catecholamines could be liberated from the fiber by the addition of acetic acid. A good linearity was observed for catecholamines in the range of 2.0–200 ng mL?1 (NE, E and DA). The detection limits of catecholamines (signal‐to‐noise ratio = 3) were 0.5 ng mL?1 (NE), 0.2 ng mL?1 (E) and 0.2 ng mL?1 (DA), respectively. Under the optimized conditions, the absolute recoveries of the above three catecholamines were 90.6% (NE), 88.5% (E) and 94.5% (DA). The repeatability of extraction performance was from 5.4 to 9.2% (expressed as relative standard deviation). Our results indicate that the proposed method could be used for the determination of NE, E and DA in urine. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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CdS sensitized NiO electrode was used as the photoactive cathode in a photoelectrochemical cell for water splitting,avoiding the use of a sacrificial electron donor.Photocurrent increment under visible light irradiation was observed after integration of[Co(dmgH)2(4-Me-py)Cl](1) to the photocathode,suggesting 1 could accept electrons from photoexcited CdS for water reduction and NiO could move the holes in the valence band of CdS to anode for water oxidation. 相似文献