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21.
Zhang X Jiang X Zhang K Mao L Luo J Chi C Chan HS Wu J 《The Journal of organic chemistry》2010,75(23):8069-8077
A facile route has been developed for the preparation of a new family of contorted 1.2,3.4,7.8,9.10-tetrabenzocoronenes (TBCs). A two-step cyclization reaction, i.e., oxidative photocyclization followed by FeCl(3)-mediated intramolecular cyclodehydrogenation, was carried out on the olefin precursors to obtain the final TBC compounds. These new TBC molecules have contorted conformation due to steric overcrowding as disclosed by single-crystal crystallographic analysis. Nevertheless, they showed extended π-conjugation compared with coronene and exhibited strong aggregation in solution. The thermal behavior and self-assembly of TBC-C8 in solid were studied by a combination of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). Compound TBC-C8 showed very good thermal and photostability and exhibited long-range ordered π-stacking in the bulk state. Moreover, uniform nanofibers with tens of micrometer length are formed in the drop-casted thin films. TBC-C8 also possesses a desirable HOMO energy level (-5.10 eV), which allows efficient charge injection from electrodes such as gold electrode. The charge carrier mobilities were determined by using the space-charge limited-current (SCLC) technique and high average hole mobility of 0.61 cm(2) V(-1) s(-1) was obtained for TBC-C8. 相似文献
22.
A new strategy to construct amperometric immunosensor for human IgG assay based on ZnO/chitosan composite as sensing platform has been described. This material, which combined the advantages of inorganic species, ZnO and organic polymer, chitosan, can maintain biological activity well. A sequential sandwich immunoassay format was performed on the ZnO/chitosan composite supported by glass carbon electrode (GCE) using goat-anti-human IgG antibody (IgG Ab) and human IgG as a model system. Amperometry was used to determine the amount of horse-radish peroxidase (HRP) fixed on the sensor surface, which was related to the content of the desired human IgG. Assay conditions that were optimized included the amount of labeled antibody, the incubation time and temperature, the pH of the substrate solution, etc. Using hydroquinone as a mediator, amperometric detection at −150 mV (versus SCE) resulted in a detection range 2.5-500 ng mL−1, with a detection limit of 1.2 ng mL−1. The simple manipulations of the construction of ZnO/chitosan composite, as well as low-cost and broad linear range, are the main features of the proposed immunosensing method. 相似文献
23.
Li Mian Yang Er Shen Zhenzhou Lv Xizhi Ni Yongxin Yang Jishan Ma Li 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2285-2293
Journal of Radioanalytical and Nuclear Chemistry - Differences in the net soil loss and apportionment of wind from water erosion on hillslopes were analyzed and evaluated quantitatively through... 相似文献
24.
In this paper, regularity criterion for the 3‐D density‐dependent magnetohydrodynamic equation is considered. It is proved that the solution keeps smoothness only under an integrable condition on the velocity field in multiplier spaces. Hence, it turns out that the velocity field plays a dominant role in the regularity criteria of the weak solutions to this nonlinear coupling problem even with density. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
25.
23Na NMR方法观察硒缺乏对大白鼠红细胞钠离子浓度的影响 总被引:1,自引:1,他引:0
用无损伤23Na NMR检测技术测定了正常和低硒饲料喂养的大白鼠的红细胞内钠离子浓度.结果表明:(1)缺硒可引起胞内钠离子浓度升高,(2)高钠细胞比正常细胞易溶血,(3)在饲料中补充Na2SeO3后可使胞内钠离子浓度恢复至正常水平,溶血情况也有所改善. 相似文献
26.
ONEXISTENCE,UNIQUENESSANDREGULARITYOFSTEADYSTATESOLUTIONSTOTHEBASICSEMICONDUCTOREQUATIONSWangYuanming(王元明)FanJishan(樊继山)(Dept... 相似文献
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28.
This paper studies the Cauchy problem of the MHD equations with mass diffusion. We use the Tikhonov fixed point theorem to prove a local‐in‐time well‐posedness theorem. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
29.
Jishan Fan Hongjun Gao Boling Guo 《Mathematical Methods in the Applied Sciences》2011,34(17):2181-2188
The low Mach number limit for classical solutions of the compressible magnetohydrodynamic equations without thermal conductivity is, here, studied. A uniform existence result for the Cauchy problem in is proved under the assumption that the initial data are uniformly bounded with respect to the Mach number in and are well‐prepared in . Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
30.
Doubly and triply linked porphyrin-perylene monoimides 3 and 4, with extraordinary stability, large dipole moments, and strong near IR absorption, were prepared by means of one-pot oxidative cyclodehydrogenation promoted by FeCl(3). 相似文献