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11.
Hongbo Zhu Ziping Cao Xin Meng Laijin Tian Guang Chen Xuejun Sun Jinmao You 《Tetrahedron》2017,73(24):3310-3315
Acid-mediated domino reaction of ortho-carbonylated alkynyl-substituted arylaldehydes with phenols is described. The implement of this reaction can provide directly a variety of tetracyclic indeno[2,1-c]chromen-7-one products in good yields. The mechanism was proposed to be a domino indanone ring formation/ortho-alkylation of phenols/dehydrated cyclization for the formation of polycyclic skeleton. In addition, several interesting dimeric products containing a pentacyclic scaffold were also afforded stereoselectively albeit in moderate yields. The present transformations feature the use of simple acid catalyst, short reaction time and good substrate scope. 相似文献
12.
Leilei Wang Wei Wei Daoshan Yang Huanhuan Cui Huilan Yue Hua Wang 《Tetrahedron letters》2017,58(51):4799-4802
A facile and efficient one-pot method has been developed for the construction of alkynyl sulfones via direct cross-coupling reaction of aryl alkynyliodines and arylsulfinic acids. The present transformation could be accomplished under catalyst- and additive-free conditions, providing a series of alkynyl sulfones in moderate to good yields with favorable functional group tolerance. 相似文献
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14.
(黄家寅)(秦圣立)THEPROBLEMSOFNONLINEARBENDINGFORORTHOTROPICRECTANGULARPLATEWITHFOURCLAMPEDEDGES¥HuangJiayin;QinShengli(QufuNormalUn... 相似文献
15.
Laibin Zhang Tingqi Ren Xiuqin Yang Liuzhu Zhou Xiaoming Li 《International journal of quantum chemistry》2013,113(19):2234-2242
The interactions between a size‐expanded Guanine analogue x‐Guanine (xG) and gold nanoclusters, Aun (n = 2, 4, 6, and 8), were studied theoretically using density functional theory. Geometries of neutral complexes were optimized using the B3LYP functional with the 6‐31+G(d,p) basis set for xG and the LANL2DZ basis set for gold clusters. The binding modes, interaction strength, and the charge‐transfer properties of different Aun‐xG complexes were investigated. Natural population analysis was performed for natural bond order charges. It was found that gold nanoclusters form stable complexes with xG and these binding results in a substantial amount of electronic charge being transferred from xG to the gold clusters. The vertical first ionization potential, electron affinity, Fermi Level, and the HOMO–LUMO gap of xG and its complexes with gold nanoclusters were also analyzed. © 2013 Wiley Periodicals, Inc. 相似文献
16.
Xinguang Zhang Lishan Liu Yonghong Wu 《Communications in Nonlinear Science & Numerical Simulation》2013,18(6):1400-1409
By using the fixed point theorem of the mixed monotone operator, the uniqueness of positive solution for a singular fractional differential system involving derivatives is established. An example is then given to illuminate the application of the main results. 相似文献
17.
Cheng Xin Kong De-Sheng Wang Ze Feng Yuan-Yuan Li Wen-Juan 《Journal of Solid State Electrochemistry》2017,21(5):1467-1475
Journal of Solid State Electrochemistry - The TiO2/solution interfacial junction is of scientific and practical importance in the field of photoelectrochemical water splitting. Illumination of this... 相似文献
18.
Methodology and Computing in Applied Probability - We introduce a new class of multivariate elliptically symmetric distributions including elliptically symmetric logistic distributions and Kotz... 相似文献
19.
Jing Zhihong Ling Baoping Yu Yang Qi Wei Zhang Shufang 《Journal of Sol-Gel Science and Technology》2015,73(1):112-117
Journal of Sol-Gel Science and Technology - A novel gas sensing material, La–Y co-doped TiO2 nanoparticles, was synthesized by sol–gel method and applied to detect organic pollutants... 相似文献
20.
S. G. Li Q. Gong C. F. Cao X. Z. Wang J. Y. Yan Y. Wang H. L. Wang 《Optical and Quantum Electronics》2014,46(5):623-640
Since the external cavity quantum dot laser was first demonstrated, the performances have been improved in terms of operation temperature, output power, pulse generator and tuneability based on the naturally size fluctuation of quantum dot. Nowadays, the external cavity quantum dot sources have been successfully used in different absorption spectroscope techniques, in industry, biomedical and research. In this paper we reviewed the recent developments of quantum dot lasers operated in a grating-coupled external cavity system where a single frequency and wide tunable wavelength range were easily obtained by adjusting the grating angle. In all cases, we mainly stressed the significant progresses in understanding of basic optical and electronic properties to enable the importance steps forward. The prospects for further progress directed towards stability, mode-hoping-free tuning range, miniaturization and integration of the external cavity quantum dot lasers also reviewed. 相似文献