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991.
The performance of a newly designed, polyaniline activated carbon, hybrid electrochemical capacitor was evaluated. The polyaniline was prepared by the chemical oxidation/polymerization process. The capacitor was assembled by using polyaniline as a positive electrode and an activated carbon as a negative electrode respectively. From a cyclic voltammograms test, a specific capacitance of 420 F/g was obtained for polyaniline electrode. The cycle life of the cell is proved to be more than 1000 times by the Galvanostatic charge and discharge test. Values for the specific energy and real specific power of 15.5 Wh/kg and 2.8 W/g, respectively, are demonstrated for a cell voltage between 0.0 and 1.4 V. The max specific power for the hybrid capacitor amounts to 20.4 W/g. 相似文献
992.
The kinetics of Zn(II), Cd(II), and Hg(II) incorporation into meso tetrameta-tolueneporphyri n (H2T(m-CH3)PP) in acetone have been studied by means of stopped-flow method. A unified reaction mechanism was proposed and the kinetic parameters were obtained by nonlinear least-square methods. The effect of ionic strength (I) on Cd(II)/H2T(m-CH3)PP was investigated. It has been found that there is a negative kinetic salt effect and the relationship of rate constants with ionic strength was obtained. Some solvent effects have also been investigated in this article. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet 30: 277–283, 1998. 相似文献
993.
Nanoscale Distribution of Transforming Growth Factor Receptor on Post‐Golgi Vesicle Revealed by Super‐resolution Microscopy 下载免费PDF全文
Hefei Ruan Dr. Jianqiang Yu Dr. Jinghe Yuan Nan Li Prof. Xiaohong Fang 《化学:亚洲杂志》2016,11(23):3359-3364
Transforming growth factor‐β (TGF‐β) type II receptor (TβRII) plays a critical role in the initiation of TGF‐β signaling pathway; therefore, the study of its synthesis and transport processes is of great important. In this work, we achieved super‐resolution imaging of a new type of TβRII‐containing post‐Golgi vesicle by our home‐built stimulated emission depletion (STED) microscope. We visualized the ring‐shaped structure of these vesicles containing newly synthesized TβRII in the cytoplasm and characterized their size distribution from 300 to 1000 nm. These vesicles could be swollen by chloroquine treatment. Further investigation revealed that TβRII formed clusters on the outer ring of the post‐Golgi vesicles. This study offers new information on the intracellular transportation of TGF‐β receptors for better understanding its signaling process. 相似文献
994.
D. Zhang W. H. Peng Q. Lin Y. L. Li Z. H. Tao Q. R. Ruan T. Y. Zhang 《Laser Physics》2011,21(10):1712-1716
We report for the first time, to the best of our knowledge, a Yb:YAG laser operating in a CW on the three-level laser at 968
nm, based on the 2
F
5/2-2
F
7/2 transition, generally used for a 1030 nm emission. The use of a pump module with 16 passes through the crystal allowed the
realization of a Yb:YAG thin-disk laser with 507 mW of continuous wave (CW) output power at 968 nm. Moreover, intracavity
second-harmonic generation (SHG) has also been achieved with a power of 58 mW at 484 nm by using a BiB3O6 (BIBO) non-linear crystal. 相似文献
995.
二次电子发射直接影响法拉第探测器测量质子束流的精度,减小或消除二次电子发射的影响是提高束流测量精度的关键。根据二次电子补偿原理设计了二次电子补偿型同轴法拉第探测器,实验发现探测器测量质子束流强度时不能完全实现二次电子补偿。为改进和完善探测器的设计,从理论上分析了补偿片未能完全消除二次电子对束流测量影响的原因,是由于补偿片前向发射二次电子数目大于收集极后向发射二次电子数目所致。为此设计了质子束穿过金属箔发射二次电子测量装置,测量得到能量为5~10 MeV质子穿过10 m厚铜箔时前向与后向发射二次电子产额,验证了理论分析的正确性。 相似文献
996.
Ju-Ping Zhang Qin Li Cheng Zhang Pu Li Li-Juan Chen Yi-Hui Wang Xiang-Hui Ruan Wei Xiao Wei Xue 《Chemical Papers》2018,72(9):2193-2202
A series of penta-1,4-dien-3-one containing a benzotriazin-4(3H)-one moiety were prepared and evaluated for their antibacterial and antiviral activities. Bioassays indicated that some compounds exhibited good antibacterial and antiviral activities. Among them, the EC50 values of compound 6d against Xanthomonas axonopodis pv. citri and compound 6l against Ralstonia solanacearum were, respectively, 22.45 and 34.77 μg/mL, which were better than that of thiodiazole copper (51.35 and 87.26 μg/mL, respectively). Meanwhile, some title compounds were found to show remarkable antiviral activities against tobacco mosaic virus (TMV). These results indicated that penta-1,4-dien-3-one derivatives containing benzotriazin-4(3H)-one moiety could play significant roles in searching for novel agrochemicals. 相似文献
997.
Min Ruan Cheng-Gang Niu Pin-Zhu Qin Guang-Ming Zeng Zhao-Hui Yang Hui He Jing Huang 《Analytica chimica acta》2010,664(1):95-99
A two-probe tandem DNA hybridization assay based on time-resolved fluorescence was employed to detect Escherichia coli strain. The amino modified capture probe was covalently immobilized on the common glass slide surface. The Eu(TTA)3(5-NH2-phen) with the characteristics of long lifetime and intense luminescence was labeled with reporter probe. The original extracted DNA samples without the purification and amplification process were directly used in the hybridization assay. The concentration of capture probe, hybridization temperature, hybridization and washing time were optimized. The detection limit is about 1.49 × 103 CFU mL−1E. coli cells, which is comparable to the value of most microbiology methods. The proposed method has the advantages of easy operation, satisfactory sensitivity and specificity, which can provide a promising technique for monitoring the microorganisms. 相似文献
998.
氢氧化2,9,16,23-四羧基酞菁合铁(Ⅲ)与硫醇轴配反应 总被引:1,自引:0,他引:1
用分光光度法研究了酞菁合铁[Fe(Ⅲ)Pc(COOH)4OH-]与β-羟基乙硫醇(HOCH2CH2SH)的轴向配位反应热力学,求得了配位数(n),稳定常数(βn)及热力学参数ΔrH0m、ΔrS0m。用停流法研究了[Fe(Ⅲ)Pc(COOH)4OH-]与β-羟基乙硫醇及苯硫酚的轴配反应动力学,讨论了反应机理,求得了预平衡步的平衡常数(K)和速控步的速率常数(k);研究了温度等诸因素对反应动力学的影响,得到了预平衡的ΔrH0m、ΔrS0m和速控步的活化参数Δ≠Hm、Δ≠Sm 相似文献
999.
1000.
L.P. Peng L. Fang X.F. Yang H.B. Ruan Y.J. Li Q.L. Huang C.Y. Kong 《Physica E: Low-dimensional Systems and Nanostructures》2009,41(10):1819-1823
In-doped ZnO (ZnO:In) transparent conductive thin films were deposited on glass substrates by RF magnetron sputtering. The effect of substrate temperature on the structural, electrical and optical properties of the ZnO:In thin films was investigated. It was found that higher temperature improves the crystallinity of the films and promotes In substitution easily. ZnO:In thin films with the best crystal quality were fabricated at 300 °C, which exhibit a larger grain size of 29 nm and small tensile strain of 0.9%. The transmittance of all the films was revealed to be over 85% in the visible range independence of the substrate temperatures and the lowest resistivity of ZnO:In thin films is 2.4×10−3 Ω cm. 相似文献