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Ji D.,Sichuan Normal University | Su L.,Sichuan Normal University | Zhang C.,Sichuan Normal University | Zhang C.,Key Laboratory of Advanced Functional Materials
Chinese Journal of Organic Chemistry | Year: 2012

Polymethoxy-substituted phenanthrene-9-carboxylic acid or methylate is key intermediate for synthesis of tylophora alkaloids. (E)-4-(3, 4-Dimethoxybenzylidene)-6, 7-dimethoxy-1H-isochromen-3(4H)-one (6), oxided by 2, 3-dichloro-5, 6-dicyanobenzoquinone (DDQ)/CH3SO3H in CH2Cl2, gave no polymethoxy-substituted phenanthrene derivative (1) but unexpected 3-(2-(hydroxymethyl)-4, 5-dimethoxyphenyl)-6, 7-dimethoxy-2H-chromen-2-one (2) and 4, 5-dimethoxy-2-(6, 7-dimethoxy-2-oxo-2H- chromen-3-yl)benzaldehyde (3). Further experiments showed that the steric hindrance of a ring of isochromen-3-one (6) resulted in coumarin (2) not phenanthrene derivative (1), supported by comparative experiments of 2, 3-diphenylacrylic acid (10, 12). The possible mechanism of 2 via radical cation and 3 through oxidation of precursor of 2 was proposed based on the result of experiments. Source

Zhao J.,Capital Medical University | Tang H.,Capital Medical University | Gu J.,Beijing University of Technology | Wang B.,Key Laboratory of Advanced Functional Materials | And 2 more authors.
Orthopedics | Year: 2010

As a new drug delivery system, calcium phosphate cement was fabricated with different concentrations of alendronate (2, 5, 10 wt%), which is widely used to treat diseases related to bone loss. This study investigated the properties of the novel composite alendronate-loaded calcium phosphate cement in vitro, and found that the structure and chemical properties of the composites were not different from the calcium phosphate cement. However, the calcium phosphate cement set time was significantly faster compared with other groups (P<.01), and the strength of the calcium phosphate cement was significantly greater than the other groups (P<.01). The alendronate release rate from the composite increased with increase in drug concentration in the cement, and release was sustained over 21 days. The composite showed good biocompatibility in terms of the proliferation of rat mesenchymal stem cells. The alendronate-loaded calcium phosphate cement displayed satisfactory properties in vitro, which may be of benefit locally for osteoporotic bone in vivo. Source

Wang Z.,Hefei University of Technology | Wang Y.,Hefei University of Technology | Wang Y.,Rice University | Shu X.,Hefei University of Technology | And 9 more authors.
RSC Advances | Year: 2016

Highly ordered TiO2 nanotube arrays (TNAs) modified by other materials with enhanced conductivity and capacitance have been considered to be promising anode materials for supercapacitors. In this work, carbon@TiO2 nanotube arrays (CTNAs) were firstly synthesized through a calcination process under an Ar atmosphere. Then the hierarchical three-dimensional MnO2/carbon@TiO2 nanotube arrays (CMTNAs) were further developed via hydrothermal deposition of uniformly dispersed MnO2 nanoparticles with the help of the in situ reduction effect of the as-obtained carbon layers. The CTNA electrode exhibited a high area capacitance of 5.58 mF cm-2 at a scan rate of 100 mV s-1, which is about 11 times higher than that of the TiO2 nanotube arrays annealed under an air atmosphere (ATNAs). The highest gravimetric capacitance 521.4 A g-1 was achieved with the CMTNAs at a current density of 2 A g-1, and 88.6% of the initial capacitance could be maintained at a current density of 5 A g-1 up to 2000 cycles via a galvanostatic charge-discharge test. © 2016 The Royal Society of Chemistry. Source

Cao G.,Hefei University of Technology | Cao G.,Key Laboratory of Advanced Functional Materials | Zhang Y.,Hefei University of Technology | Zhang Y.,Key Laboratory of Advanced Functional Materials | And 15 more authors.
Materials Letters | Year: 2015

Novel one-dimensional (1D)/two-dimensional (2D) hybrids of sodium tungsten oxide@carbon nanocables anchored on reduced graphene oxide (rGO) nanosheets were successfully synthesized by a facile sonochemical method followed by annealing without extra carbon sources. Morphology, structure and chemical states of the hybrids were characterized by scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy techniques. The characterization results indicate that the nanocable structure is composed of single crystalline Na0.1WO3 nanorod wrapped with thin graphitic carbon layer. Optical absorption peak of the hybrids demonstrates an evident red shift compared with physical mixture of sodium tungsten oxide/rGO, which indicates hybridization effect between the nanocables and the rGO nanosheets and promises potential of the hybrids for various nanodevice applications. © 2015 Elsevier B.V. All rights reserved. Source

Zhang J.,Key Laboratory of Advanced Functional Materials | Zhang J.,Hefei University of Technology | Wang Y.,Key Laboratory of Advanced Functional Materials | Wang Y.,Hefei University of Technology | And 11 more authors.
New Journal of Chemistry | Year: 2014

Heterojunction composites based on n-type TiO2 nanotubes arrays (TNAs) coupled with p-type Cu2O nanoparticles were synthesized using a square wave voltammetry deposition method for in situ deposition of Cu2O nanoparticles onto the inner surfaces and interfaces of TNAs. The prepared samples were characterized by field-emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and UV-vis spectroscopy. When compared with pure TNAs, the Cu2O-TNAs heterojunction composites exhibit considerably higher photocurrent density under visible-light irradiation and enhanced photocatalytic activity for the visible-light-driven photodegradation of methyl orange. Moreover, the photocurrent densities and photocatalytic activity of the Cu2O-TNAs heterostructures largely depend on the deposition potential which determines the content of the Cu2O nanoparticles. The Cu2O-TNAs prepared by the deposition potential of -1.0 V showed the highest photocurrent density (0.91 mA cm-2) and the largest photodegradation rate of methyl orange (88.8%) at the applied potential of 0.5 V under visible light irradiation. The enhanced photoelectrocatalytic activity can be attributed to reducing the recombination rate of the photoexcited electron-hole pairs in TNAs when coupled with Cu2O nanoparticles. © 2014 the Partner Organisations. Source

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