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141.
Jun Jianga Jian Zhanga Feng Gua Wei Shaoa Chunzhong Lia Mengkai Lub a Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science Engineering East China University of Science Technology Shanghai China b State Key Laboratory of Crystal Materials Sh ong University Jinan China 《中国颗粒学报》2011,(3)
For better performance of dye sensitized solar cells(DSSCs) ,a bilayer structured electrode was constructed by employing a mesoporous anatase TiO2 overlayer above a commercial P25 TiO2 nanoparticles underlayer. The mesoporous anatase TiO2,prepared through a facile surfactant-assisted sol-gel process,possessed large pore size and well inter-connected network structure,both beneficial for dye adsorption and electron transfer. The dye adsorption capability of the mesoporous TiO2 was nearly twice that of the P2... 相似文献
142.
Rong Li Guang Mei Chen Xin Lan Ma Qiao Yan Chen Ge Wen Xu Yi Ping Huang 《中国化学快报》2011,22(9):1107-1110
Terephthaloyl chloride(DB)-modified silk fibroin(SF) films were immersed into 1.5 times simulated body fluid(1.5 SBF) to regulate the mineralization of hydroxyapatite(HA) crystals at about 36.5℃for 24 h.UV was used to prove that the new bonds form between the DB and SF.The structure and morphology of the SF/HA were investigated by FTIR,ICP,XRD and SEM.The results showed that the apatite deposited on the matrix of SF mainly was HA.HA was self-assembled on the matrix of SF and formed three-dimensional framework when the weight ratio of DB/SF was 0.30.The content of DB affected the structure and morphology of the apatite composites deposited on the SF films. 相似文献
143.
Barbara Cosimelli Gabrio RoncucciDonata Dei Lia FantettiFiammetta Ferroni Micaela RicciDomenico Spinelli 《Tetrahedron》2003,59(50):10025-10030
The synthesis of new unsymmetrical substituted zinc phthalocyanines derivatives has been described; moreover the photodynamic activity of some compounds tested against Candida albicans has been reported. 相似文献
144.
145.
A new β-cyclodextrin modified hyperbranched carbosilane stationary phase for gas chromatography was synthesized by substituting the -OH groups ofβ-cyclodextrin with hyperbranched carbosilane and was coated on the inner wall of fused silica capillary column for gas chromatography.The chromatographic behaviors of the stationary phase were studied.The initial testing results showed mat it possessed good separation abilities for several kinds of mixtures,such as benzenes,acrylates,ketones and alkylchlorides. 相似文献
146.
Organo-soluble fluorinated polyimides were synthesized by the polycondensation of a new aromatic diamine α,α-bis(4-amino-3,5-dimethylphenyl)-4'-fluorophenyl methane with several aromatic dianhydrides.The one-step polymerizationprocedure was conducted at 180℃in m-cresol,producing the polyimides with inherent viscosities of 0.68-0.76 dL.g~(-1).Thepolyimides could be soluble not only in polar aprotic solvents,such as N-methyl-2-pyrrolidinone,and N,N-dimethylacetamide,but also in common organic solvents,such as chloroform,cyclopentanone,m-cresol and so on.Thepolyimide films show excellent transparency with the UV-Vis cut-off lengths of 310-360 nm and light transmittances ofhigher than 80% in the visible region.In addition,the polyimides exhibit good thermal stability with an initial decompositiontemperature(T_d)higher than 530℃and have more than 60% of residual weight retentions at 700℃. 相似文献
147.
Lia ZAHARANI Nader GHAFFARI KHALIGH Hayede GORJIAN Mohd RAFIE JOHAN 《Turkish Journal of Chemistry》2021,45(1):261
Liquid phase tandem Knoevenagel–Michael condensation of various aromatic and heteroaromatic aldehydes with barbituric acid or 2-thiobarbituric acid and malononitrile was studied in a one-pot three-component reaction. For the first time, TMDP was employed as a safe and efficient solvent and/or catalyst in the liquid and aqueous ethanol medium, respectively, for the practical and eco-friendly Knoevenagel–Michael condensation. The reactions were carried out by using greener procedures, including a) the use of TMDP as an N-heterocycle organocatalyst in a green medium including water and ethanol (1:1 v/v) at reflux temperature, and b) the use of TMDP as a dual solvent-catalyst at 65 °C in the absence of any solvent. High to excellent yields of the desired pyrano[2,3- d ]pyrimidinones were obtained under the two earlier mentioned conditions. The current methodologies have advantages, including (a) avoiding hazardous, toxic, volatile, and flammable materials and solvents, (b) avoiding tedious processes, harsh conditions, and multiple steps for the preparation of catalysts, (c) using a less toxic and noncorrosive catalyst, (d) minimizing hazardous waste generation and simple workup process, and (e) high recyclability of TMDP. Another important result of this work is that the TMDP can be a promising alternative for toxic, volatile, and flammable base reagents such as piperidine and triethylamine in liquid phase organic syntheses owing to its unique properties such as being less toxic, nonflammable, and nonvolatile, and having a low melting point, broad liquid range temperature, high thermal stability, and safe handling and storage. 相似文献
148.
149.
An assembly of Keggin polyoxomolybdate and organic substrate(Hbipy)3[PMo12O40](1,bipy=2,2’-bipyridine) was synthesized and characterized by elemental analysis,infrared spectrum,and single-crystal X-ray analysis.The ligand bipy of compound 1 was generated by a decarboxylation coupling reaction of H2pdc(H2pdc=pyridine-2,6-dicarboxylic acid) in situ under hydrothermal reaction conditions and the control experiments illustrate that La(NO3)3 or Ce(NO3)3,which does not appear in the final structure,is necessary for the decarboxylation coupling reaction.Moreover,compound 1 displays strong photoluminescence property in the solid state at room temperature. 相似文献
150.
AbstractThe viscosity of neat ionic liquids is very important for their application in organic synthesis as a solvent because most of the neat ionic liquids are very viscous, which would result in the less efficient mass transfer of reactants. In the present study, a series of novel dihydro-[1,2,4]triazolo[1,5-a]pyrimidines were prepared using a low viscous and acid-functionalized ionic liquid. Our results showed that new ionic liquid can act as a green solvent and acid catalyst due to low viscosity and acid functionality. The products were simply extracted and the ionic liquid was retrieved several times without reducing its catalytic efficiency. The current application of TMDPS in the one-pot multicomponent reactions as dual solvent-catalyst highlights the importance of low viscous acid-functionalized ionic liquids in organic synthesis, and we hope that further research will be conducted in the future to finding other applications of TMDPS with promising results. 相似文献