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991.
Zhang  Xia  Dong  Chaoyang  Sun  Yangang  Liu  Binyang  Sun  Lili  Lu  Yongjuan  Yu  Jing  Wei  Yajun  Xu  Yuandong 《Journal of Solid State Electrochemistry》2022,26(2):491-501
Journal of Solid State Electrochemistry - Grapefruit peel carbon (GPC) is prepared from waste grapefruit peel and further used as substrate for in situ construction of MoS2 arrays, forming MoS2/GPC...  相似文献   
992.
993.
Two novel styryllactones,goniodilactone(1) and gonioheptenolactone(2),were isolated from the leaves of Goniothalamus cheliensis Hu.Their structures were determined on the basis of spectroscopic data as well as X-ray crystallography analysis. Compounds 1 and 2 exhibited significant cytotoxicities in a panel of human cancer cells,including DU-145,PC-3,MCF-7,A-549, KB and KBvin,with GI50S in the range of 1.29-4.56μg/mL.  相似文献   
994.
995.
A hexagonal porphyrin‐based porous organic polymer, namely, CPF‐1, was constructed by 3+2 ketoenamine condensation of the C2‐symmetric porphyrin diamine 5,15‐bis(4‐aminophenyl)‐10,20‐diphenylporphyrin and 1,3,5‐triformylphloroglucinol. This material exhibits permanent porosity and excellent thermal and chemical stability. CPF‐1 can be employed as a superior supporting substrate to immobilize Au nanoparticles (NPs) as a result of the strong interactions between Au NPs and the CPF support. An Au@CPF‐1 hybrid was synthesized by an interfacial solution infiltration method with NaBH4 as reducing agent. Au NPs (5 nm) grew on CPF‐1 and were distributed without aggregation. Moreover, Au@CPF‐1 exhibits superior catalytic activity compared to many other reported Au‐based catalysts for the reduction of 4‐nitrophenol in the presence of NaBH4. In addition, Au@CPF‐1 has excellent stability and recyclability, and it can be reused for three successive reaction cycles without loss of activity. The dense distribution of phenyl rings on the channel walls of the CPF support can reasonably be regarded as the active sites that adsorb the 4‐nitrophenol molecule through hydrogen‐bonding and C?H ??? π interactions, as was confirmed by the X‐ray structure of model compound DAPP‐Benz.  相似文献   
996.
997.
A simple and versatile technique was developed to prepare hierarchical ZnO single crystals by introducing eggshell membrane (ESM) to a bio-inspired approach. Based on the control of nucleation and gestation, ZnO nanocrystallites could grow at three dimensions into polyhedral single crystals through a surface sol-gel process followed by a calcination treatment. Different from traditional wet chemical techniques, our synthetic process depends more on the restrictive or directing functions of the ESM biomacromolecules. The hierarchical ZnO nanostructures doped with polyhedral single crystallites could be desirable for catalysts, photoelectrochemical devices, especially solar cells.  相似文献   
998.
Wang  L. Y.  Xu  W. C.  Luo  Z. C.  Cao  W. J.  Luo  A. P.  Dong  J. L.  Wang  H. Y. 《Laser Physics》2011,21(10):1808-1812
We experimentally demonstrate a passively Q-switched mode-locking (QML) operation in an Erbium-doped fiber ring laser with net normal dispersion by using nonlinear polarization rotation technique. A 2 m long section of dispersion compensating fiber (DCF) with extra large positive dispersion was inserted into the cavity to ensure the fiber laser working in the region of net positive dispersion. By carefully adjusting the polarization controller, both uniform dissipative mode-locking pulses with fundamental repetition rate and QML pulse trains with tunable repetition rate from 71.58 to 98.83 kHz are achieved. It is found that the QML operation is caused by the interaction between the polarization state of the pulse and the intracavity polarizer.  相似文献   
999.
1000.
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