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21.
Mi Ouyang Dacheng Dai Xuming Hu Yuwen Li Zhangxin Chen Bowen Tao Lina Zhang Weijun Li Yujie Dong Ru Bai Xiaojing Lv Cheng Zhang 《Journal of polymer science. Part A, Polymer chemistry》2022,60(15):2269-2279
A new star-shaped structure conjugated microporous polymers, poly (2,8,14-tri[4-diphenyl-benzene]-hexaazatrinaphthylene) (PTPA-HATN), was designed and in-situ electrochemically polymerized on the surfaces of FTO electrodes with a directional alignment TiO2 nanorod array to obtain TiO2/PTPA-HATN core-shell nanocomposite films. Compared with the PTPA-HATN film, the TiO2/PTPA-HATN composite film exhibits higher optical contrast and faster response time, with contrast of 57% at 783 nm, coloring time of 3.62 s and discoloring time of 2.55 s (43%, 4.63 s and 4.77 s for PTPA-HATN film, respectively). After 400 cycles, the contrast of nanocomposite film decreased by 28%, while the PTPA-HATN film basically lost its electrochromic properties. A simple three-layer EC prototype device based on TiO2/PTPA-HATN nanocomposite film constructed with hydrogel electrolyte clearly shows color changes at different voltages. On the one hand, the formation of core-shell porous nanostructure of TiO2/PTPA-HATN composite film provides a larger ion doping/de-doping interface, shortening the average diffusion length of ions. On the other hand, the large indented polymer-nanorods contact interface makes it difficult for the polymer to detach from the electrode, thus significantly improving the cyclic stability of the composite film. 相似文献
22.
Vitamin K1 distribution following intravenous vitamin K1–fat emulsion administration in rats 下载免费PDF全文
Xue Xiao Yan‐Ni Mi Fa Wang Bing‐Hua Zhang Lei Cao Yong‐Xiao Cao 《Biomedical chromatography : BMC》2015,29(12):1849-1858
This study investigated vitamin K1 (VK1) distribution following intravenous vitamin K1–fat emulsion (VK1–FE) administration and compared it with that after VK1 injection. Rats were intravenously injected with VK1–FE or VK1. The organ and tissue VK1 concentrations were determined using high‐performance liquid chromatography method at 0.5, 2 and 4 h to determine distribution, equilibrium and elimination phases, respectively. In the VK1–FE group, the plasma, heart and spleen VK1 concentrations decreased over time. However, other organs like liver, lung, kidney, muscle and testis, reached peak VK1 concentrations at 2 h. In the VK1 injection group, the liver VK1 concentrations were significantly higher than those in other organs at the three time points. However, VK1 concentrations in the other organs peaked at 2 h. In addition, in VK1–FE group, the heart, spleen and lung VK1 concentrations were significantly higher than those in the VK1 injection group at the three time points, and the liver VK1 concentration was significantly higher than that in the VK1 injection group at 4 h. The VK1 amount was greatest in the liver compared with the other organs. Thus, the liver is the primary organ for VK1 distribution. The distribution of VK1 is more rapid when injected as VK1–FE than as VK1. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Jikun Li Xinxin Feng Wei Zhu Nikita Oskolkov Tianhui Zhou Boo Kyung Kim Noman Baig Prof. Michael T. McMahon Prof. Eric Oldfield 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):264-271
Diamagnetic chemical exchange saturation transfer (CEST) contrast agents offer an alternative to Gd3+‐based contrast agents for MRI. They are characterized by containing protons that can rapidly exchange with water and it is advantageous to have these protons resonate in a spectral window that is far removed from water. Herein, we report the first results of DFT calculations of the 1H nuclear magnetic shieldings in 41 CEST agents, finding that the experimental shifts can be well predicted (R2=0.882). We tested a subset of compounds with the best MRI properties for toxicity and for activity as uncouplers, then obtained mice kidney CEST MRI images for three of the most promising leads finding 16 (2,4‐dihydroxybenzoic acid) to be one of the most promising CEST MRI contrast agents to date. Overall, the results are of interest since they show that 1H NMR shifts for CEST agents—charged species—can be well predicted, and that several leads have low toxicity and yield good in vivo MR images. 相似文献
26.
Existence of 3-Dimensional Tori for 1D Complex Ginzburg–Landau Equation Via a Degenerate KAM Theorem
In this paper, we consider complex Ginzburg–Landau equation in one space dimension and rigorously show the existence of 3-dimensional tori. The proof is based on degenerate infinite-dimensional KAM theory and normal form technique. 相似文献
27.
Paweł Górnaś Inga Mišina Ilze Grāvīte Arianne Soliven Edīte Kaufmane Dalija Segliņa 《Natural product research》2015,29(13):1222-1227
Composition of tocochromanols in kernels recovered from 16 different apricot varieties (Prunus armeniaca L.) was studied. Three tocopherol (T) homologues, namely α, γ and δ, were quantified in all tested samples by an RP-HPLC/FLD method. The γ-T was the main tocopherol homologue identified in apricot kernels and constituted approximately 93% of total detected tocopherols. The RP-UPLC-ESI/MSn method detected trace amounts of two tocotrienol homologues α and γ in the apricot kernels. The concentration of individual tocopherol homologues in kernels of different apricots varieties, expressed in mg/100 g dwb, was in the following range: 1.38–4.41 (α-T), 42.48–73.27 (γ-T) and 0.77–2.09 (δ-T). Moreover, the ratio between individual tocopherol homologues α:γ:δ was nearly constant in all varieties and amounted to approximately 2:39:1. 相似文献
28.
De Novo Design and Synthesis of a γ‐Turn Peptidomimetic Scaffold and Its Application as JNK3 Allosteric Ligand 下载免费PDF全文
As a way to develop a neuroprotective agent for the JNK3‐JIP1‐binding site, peptidomimetics of JIP‐1 as JNK3 allosteric regulators have been examined. The study consisted of in silico scaffold hopping, molecular docking, solution and solid‐phase peptide syntheses, and Kd measurements using surface plasmon resonance. As a peptidomimetic of JIP1, heptamer mimetic 16 (Kd=2.72 μm ) displayed a higher affinity than decamer JIP1 (Kd=23.6 μm ). The high affinity of 16 implies that the characteristic γ‐turn mimetic structure, “”Φ‐X‐Φ“ hydrophobic motif in 16 , increased its affinity toward the JIP‐site of JNK3. 相似文献
29.
Daewha Hong KiEun Bae Dr. Duckshin Park Houngkyung Kim Seok‐Pyo Hong Mi‐Hee Kim Dr. Bong Soo Lee Dr. Sangwon Ko Prof. Dr. Seokwoo Jeon Xu Zheng Prof. Dr. Wan Soo Yun Prof. Dr. Yang‐Gyun Kim Prof. Dr. Insung S. Choi Prof. Dr. Jungkyu K. Lee 《化学:亚洲杂志》2015,10(3):568-571
Direct patterning of streptavidin and NIH 3T3 fibroblast cells was successfully achieved over a large‐area pristine graphene sheet on Si/SiO2 by aryl azide‐based photografting with the conventional UV lithographic technique and surface‐initiated, atom transfer radical polymerization of oligo(ethylene glycol) methacrylate. 相似文献
30.
Iron(III)‐Selective Chelation‐Enhanced Fluorescence Sensing for In Vivo Imaging Applications 下载免费PDF全文
Lin E. Guo Xin Yi Liu Huan Wang Qiu Ling Chen Guang Ke Wang Prof. Kaijun Luo Qi Li Mi Prof. Ying Zhou Jun Feng Zhang 《化学:亚洲杂志》2015,10(9):1898-1902
A “turn‐on” pattern Fe3+‐selective fluorescent sensor was synthesized and characterized that showed high fluorescence discrimination of Fe3+ over Fe2+ and other tested ions. With a 62‐fold fluorescence enhancement towards Fe3+, the probe was employed to detect Fe3+ in vivo in HeLa cells and Caenorhabditis elegans, and it was also successfully used to elucidate Fe3+ enrichment and exchange infected by innexin3 (Inx3) in hemichannel‐closed Sf9 cells. 相似文献