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31.
PMMA/凝胶玻璃复合材料作为非线性有机分子掺杂基质的研究 总被引:3,自引:2,他引:1
对分散红1(DR1)掺杂聚甲基丙烯酸甲酯(PMMA)/凝胶玻璃复合材料的光学二阶非线笥及其热稳定性进行了研究。结果表明,PMMA/凝胶玻璃作为一种有机/无机复合材料,是介于胶玻璃和PMMA之间的一种非线性有机分子掺杂基质。随复合材料中凝胶玻璃含量增多,所制备的非线性材料的热稳定性能变好。对非线性和热稳定性的折衷考虑,获得了制备光学二阶非线笥基质材料先体PMMA和正硅酸乙酯(TEOS)的最佳混合比例。 相似文献
32.
高中化学如何开展自主学习、合作学习、探究学习?本文认为ESFA模式改进后具有较好的效果。只要解决了“ESFA模式下教师的主导作用如何充分有效发挥”这一问题,就很容易使学生进入自主、合作、探究的学习状态。 相似文献
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34.
孙志玲 《数学物理学报(A辑)》2020,(2):304-314
该文给出了多圆盘Bergman空间上两个带有某种符号的Toeplitz算子的乘积等于另一个Toeplitz算子的充分必要条件,并且给出了乘积算子所带符号的公式.接下来,相应的研究了它的交换性.这些研究结果都是根据符号函数的Mellin变换. 相似文献
35.
完全刻画多重调和Bergman空间上Toeplitz算子和Hankel算子的紧性.运用紧Toeplitz算子这个结果,建立了Toeplitz代数和小Hankel代数的短正合列,推广了单位圆盘上相应的结果. 相似文献
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37.
Tao Wan Denghui Wang Junyan Hu Zhiling Zhou Haibo Zhang Daolu Bu 《Journal of Dispersion Science and Technology》2014,35(1):7-13
The effect of the addition of sodium 4-styrenesulfonate (SSS) and KNO3 as well as temperature and shear rate on the structural transition of aqueous micellar solutions of the cationic surfactant cetyl trimethyl ammonium bromide (CTAB) was studied by viscosity. The effect of hydrocarbons on viscoelastic CTAB solutions was also examined. Possible mechanism for formation of CTAB wormlike micelles in the presence of sodium 4-styrenesulfonate (SSS) and KNO3 was discussed. The rapid increase in the apparent viscosity of CTAB solutions on the addition of SSS and KNO3 was due to the transition in micellar shape from spheres to wormlike ones. The rheological properties of CTAB solutions fit Maxwell model at low shear frequency. AFM image indicated a structure of transient network of CTAB/SSS/KNO3/H2O solution. 相似文献
38.
Chen Y Yang J Wang Z Wu X Wang F 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(3):686-690
Scopoletine (SLT), 7-hydroxy-6-methoxylcoumarin, is known to possess biological activities such as abirritating and anti-tumor, it can quench intrinsic fluorescence of bovine serum albumin (BSA) and the fluorescence intensity of itself is enhanced. So, SLT is used as fluorescence probe for quantitative determination of protein. The experiments indicate that under optimum conditions, the enhanced intensity of fluorescence is in proportion to the concentration of proteins in a wide range, and their detection limits (S/N=3) are 1.4 x 10(-8)g mL(-1) for BSA and 1.1 x 10(-8)g mL(-1) for HSA, respectively. Samples were satisfactorily determined. The interaction mechanism is also discussed. 相似文献
39.
A Convenient and Efficient Synthesis of 2‐Thioxoquinazolinone Derivatives via Microwave Irradiation
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Weiwei Liu Qiang Zhang Feng Gong Zhiling Cao Yunfeng Huo 《Journal of heterocyclic chemistry》2015,52(2):317-321
The synthesis of 2‐thioxoquinazolinone derivatives was achieved by condensation of isatoic anhydride, primary amine, and carbon disulfide under microwave irradiation. This convenient and efficient method affords the desired products with good to excellent yields. Satisfactory infrared spectroscopy, 1H NMR, and high‐resolution mass spectrometry (electrospray ionization) spectra were obtained for all compounds described. 相似文献
40.
Dr. Mohammed J. Meziani Dr. Wei‐Li Song Ping Wang Dr. Fushen Lu Dr. Zhiling Hou Ankoma Anderson Dr. Halidan Maimaiti Prof. Ya‐Ping Sun 《Chemphyschem》2015,16(7):1339-1346
Hexagonal boron nitride nanosheets (BNNs) are analogous to their two‐dimensional carbon counterparts in many materials properties, in particular, ultrahigh thermal conductivity, but also offer some unique attributes, including being electrically insulating, high thermal stability, chemical and oxidation resistance, low color, and high mechanical strength. Significant recent advances in the production of BNNs, understanding of their properties, and the development of polymeric nanocomposites with BNNs for thermally conductive yet electrically insulating materials and systems are highlighted herein. Major opportunities and challenges for further studies in this rapidly advancing field are also discussed. 相似文献