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151.
Ting Chen Baojie Zhang Zhi Liu Lian Duan Guifang Dong Ying Feng Xinyu Luo Deliang Cui 《Tetrahedron letters》2017,58(6):531-535
Carbazole-based diaza[7]helicene substituted by thiophene groups, 2,12-dithiophene-5,15-dihexyl-5,15-diaza[7]helicene (6), was synthesised successfully and confirmed by 1H NMR, 13C NMR, High Resolution Mass Spectrometry, Time of Flight Mass Spectrometry. Compound 6 exhibited good solubility and excellent thermal stability with no melting point and a high decomposition temperature of 453.64 °C. A doped device with a structure of ITO/NPB (50 nm)/CBP: 10% 6 (30 nm)/Bphen (20 nm)/Mg:Ag (150 nm)/Ag (50 nm) emitted the blue light at 460 nm with Commission Internationale de LEclairage (CIE) coordinate of (0.176, 0.26). The maximum brightness and external quantum efficiency (EQE) were 2306 cd m?2 and 0.41%, respectively. 相似文献
152.
153.
Fulin?Zhou Xiang?Cui Anqi?Shang Jinyu?Lian Luzhu?Yang Yan?Jin Baoxin?LiEmail author 《Mikrochimica acta》2017,184(3):773-779
The authors report on a simple strategy for sensitive determination of the activity of terminal deoxynucleotidyl transferase (TdT) using copper nanoclusters (CuNCs) as fluorescent probes. TdT-polymerized long chain AT-rich DNA serves as a template for the synthesis of the CuNCs, and TdT activity is detected fluorometrically at excitation/emission wavelengths of 340/570 nm. The protocol relies on the target-triggered formation of dsDNA polymers and in-situ formation of CuNCs. The calibration plot is linear in the 0.7 to 14 U L?1 activity range, with a 60 mU L?1 detection limit (at a signal-to-noise ratio of 3). The protocol was applied to determine TdT activity in acute lymphatic leukemia cells. This approach is selective, simple, convenient and cost-efficient because a complex DNA sequence is not required. In our perception, the method provides a viable new platform for monitoring the activity and inhibition of TdT. 相似文献
154.
Hua-Yong Lou Lian Jin Tao Huang Dao-Ping Wang Guang-Yi Liang Wei-Dong Pan 《Tetrahedron letters》2017,58(5):401-404
Three new diterpenoids, vulgarisins B–D (1–3), have been isolated from a medicinal plant Prunella vulgaris Linn. These diterpenoids contain a rare 5/6/4/5 fused tetracyclic ring skeleton. Their structures were determined through the analysis of spectroscopic data, and the absolute configuration were further confirmed by single crystal X-ray diffraction as well as CD analysis. All the compounds were evaluated for their cytotoxicity activity, vulgarisins B (1) and C (2) demonstrated modest cytotoxicity activity against human lung carcinoma A549 cell line. 相似文献
155.
一种铈(Ⅲ)配合物对含石墨粘结涂层耐蚀性的影响 总被引:1,自引:0,他引:1
为了改善含石墨粘结涂层的耐蚀性,首先对这种涂层在腐蚀环境中耐蚀性差的原因进行了分析,然后将二正丁基磷酸、CeF_3、Sb_2O_3和一种Ce(Ⅲ)配合物Ce(NO_3)(C_8H_(18)PO_4)_2分别添加于酚醛环氧-MoS_2-石墨粘结涂层中,考察了它们对这种涂层耐蚀性的影响,并对含Ce(NO_3)(C_8H_(18)PO_4)_2的涂层和空白样涂层进行了表面分析。盐雾试验表明,添加Ce(NO_3)(C_8H_(18)PO_4)_2可以有效地抑制涂层中MoS_2的氧化和由石墨所引起的金属底材之电化学腐蚀;根据X射线光电子能谱分析结果可知,添加Ce(NO_3)(C_8H_(18)PO_4)_2之所以能够提高含石墨粘结涂层的耐蚀性,应当归因于它在MoS_2晶体表面和金属底材表面的吸附。因此,Ce(Ⅲ)配合物Ce(NO_3)(C_8H_(18)PO_4)_2是含石墨粘结涂层的一种实用性能良好的新型防腐添加剂。 相似文献
156.
多化学组份反应气体流动的Godunov格式 总被引:1,自引:0,他引:1
本文将单介质气体流动的Goduoov方法推广到多化学组份气体流动的计算中,建立了多化学组份气体的间断分解公式以及任意四边形网格下的Godunov方法的差分格式,提出了处理自由边界的虚相法,应用第二类网格,计算了超音速射流及其冲击问题的几个算例,并且同实验结果进行了比较。 相似文献
157.
真实火箭射流冲击流场中激波结构的实验研究 总被引:3,自引:0,他引:3
本文采用一种有效的激光-莫瑞光栅干涉系统首次拍摄到真实火箭燃气射流冲击流场的激波结构.解决了长期以来无法拍摄到高温、高速、强火焰光的火箭射流流场图像的问题。利用这一系统,研究了射流冲击流场中激波结构的一些变化规律,发现了一些新的激波结构。较系统地研究了欠膨胀射流冲击各种锥体的激波形态。 相似文献
158.
Synthesis, spectroscopic and electrochemical property of an unsymmetrical porphyrin and its Zn compound 总被引:1,自引:0,他引:1
Chang Fu Zhuang Yu Jing Zhang Ai Qing Xia Wen Hui Lian Yun Fang Wang Ping Zhang Tong Shun Shi 《中国化学快报》2010,21(7):769-773
<正>In this article,a new 5-(p-maleicaminophenyl)-10,15,20-triphenylporphyrin(H_2P) and relative zinc compound(ZnP) were synthesized and characterized by means of elemental analyses,UV-vis,IR,MS and ~1H NMR spectroscopies.Furthermore,we have investigated the fluorescence spectroscopy of these compounds.The oxidation and reduction properties of the compounds were studied by the cyclic voltarnmetry,the oxidation-reduction potentials were obtained. 相似文献
159.
<正>Two new ceramides,(2S,3S,4R)-2-N-[(2'R)-2'-hydroxypentacosanoylamino]-nonacosane-1,3,4-triol(1) and(2S,3S,4R,8E)-2- N-[(2'R)-2'-hydroxytetracosanoylamino]-8-eicosylene-1,3,4-triol(2) have been isolated from the stems of Piper betle L.collected from Baoshan city of Yunnan Province in China.Their structures were determined by spectroscopic and chemical methods. 相似文献
160.
<正>Europium(Ⅲ)-doped YF_3 is prepared by a hydrothermal process at 200℃.X-ray diffraction(XRD) pattern identifies the formation of YF_3 phase without detectable impurity.Environment scanning electron microscopy(ESEM) image shows the even size distribution of the samples with cubic morphology.The excitation and emission spectra of the rare earth ions doped YF_3 are investigated by fluorescence spectrophotometer.The excitation spectrum for 591 nm emission has several excitation bands at 320, 365,386,397 and 467 nm,and the main peak value was 397 nm.Typical Eu~(3+) emission peaks at 591 nm(~5D_0→~7F_1) and 612 nm (~5D_0→~7F_2) are observed when excited by 397 nm,and the strongest emission is 591 nm,demonstrating that the rare earth ions occupy the centrosymmetrical sites in YF_3. 相似文献