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961.
962.
963.
Junhua Xiao Gu Yuarf Weiqiang Huang John H. K. Lum K‐L Daniel Lee Albert S. C. Chan 《中国化学会会志》2001,48(5):929-932
Two nitrated analogs of distamycin were synthesized by a novel haloform reaction and the DCC/HOBT coupling reaction in a convenient and effective way with out amino group protection. Our results have demonstrated that these polyamides show DNA cleaving activity under long UV (LUV 365 nm) irradiation. Furthermore, it is an unexpected discovery that these analogs can prevent DNA dam age under short UV (SUV 302 nm). 相似文献
964.
Eu3+-doped oxy-phosphate (La3PO7:Eu3+) with monoclinic phase has been synthesized via solid phase and co-precipitation methods. The products present various regular morphologies after high temperature thermal treatment, such as bulk with holes, leaf-like flake, nano-rod and so on. All the phosphors exhibit the characteristic fluorescence of Eu ion, the electric dipole transition 5D0→7F2 of Eu3+ ions is dominant indicating that the sites of Eu3+ ions in La3PO7 have no the inversion center. Furthermore, the intensity of 5D0→7F2 increases due to the introducing of surfactant and increasing of the calcination temperature. 相似文献
965.
A synthesis of the dibenz[b,d]azonine atropisomers (14) from 2-phenylbenzoic acid is described. This heterocycle belongs to a new series of biaryl compounds with potential antitubulin activity. 相似文献
966.
The calculations of the P-V isotherms, Hugoniots, dissociation and ionization degrees of fluid (liquid) hydrogen isotopes have been performed by using the self-consistent fluid variational theory under isothermal and shock compression. The isotope effect of fluid hydrogen was discussed. The present results are compared with the available experiments and calculations. 相似文献
967.
Computational conformal geometry is an inter-disciplinary field between mathematics and computer science. This work introduces
the fundamentals of computational conformal geometry, including theoretic foundation, computational algorithms, and engineering
applications. Two computational methodologies are emphasized, one is the holomorphic differentials based on Riemann surface
theory and the other is surface Ricci flow from geometric analysis. 相似文献
968.
969.
Guangfeng Wang Aixia Gu Wen Wang Yan Wei Jingjing Wu Guozhong Wang Xiaojun Zhang Bin Fang 《Electrochemistry communications》2009,11(3):631-634
This communication reports on a novel amperometric hydrazine sensor of CuO nanoarray based on a Cu substrate. Copper oxide nanoarray was directly grown on Cu substrates using a one-step facile hydrothermal method and was characterized using scanning electron microscopy and X-ray powder diffraction. The electrochemical study has shown that the CuO nanoarray exhibits higher catalytic effect on the hydrazine than the normal CuO nanoparticles. This may be attributed to the special structure of the nanomaterials esp. the substrate of the electric Cu. And the amperometric response showed that the CuO nanoarray modified glassy carbon electrode has a low detection and a high sensitivity for hydrazine. 相似文献
970.
Through the functionalization of multiwalled carbon nanotubes (MWCNTs) by 0,0′‐diallylbisphenol A (DBA), the interface situation between MWCNTs and bismaleimide (BMI) was improved, as detected by scanning electron microscope (SEM) and dynamic mechanical analysis (DMA). The improved interface situation was considered to be the main reason for the huge increased microhardness value and greatly improved the microtribological property of MWCNTs/BMI composites. Besides, the wear mechanism for the composite was also believed to be related to the interfacial situation. The rough wavelike worn surface of pure BMI resin is attributed to its poor load capacity. The smoother waterfall‐shape worn surface of MWCNTs/BMI is related to the interface formed by the addition of MWCNTs while the ultrasmooth worn surface of DBA modified MWCNTs/BMI is due to the greatly improved interfacial interaction of the composite. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献