A novel flower-like hydrated magnesium carbonate hydroxide, Mg5 (CO3 )4 (OH)2·4H2O, with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use o...A novel flower-like hydrated magnesium carbonate hydroxide, Mg5 (CO3 )4 (OH)2·4H2O, with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use of template or organic surfactant. Reaction time has an important effect on the final morphology of the product. The micro-structure and morphology of Mg5 (CO3)4 (OH)2·4H2O were characterized by means of X-ray diffractometry (XRD), fieldemission scanning electron microscopy(FE-SEM). Brunauer-Emmett-Teller(BET) surface areas of the samples were also measured. The probable formation mechanism of flower-like micro-structure was discussed. It was found that Mg5 (CO3)4( OH)2·4H2O with flower-like micro-structure was a novel and efficient catalyst for the synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol.展开更多
The one-pot synthesis of dimethyl carbonate(DMC) with co-production of propy-lene carbonate(PC) and propylene glycol(PG) from propylene oxide( PO), carbon dioxide and methanol as the starting materials was inv...The one-pot synthesis of dimethyl carbonate(DMC) with co-production of propy-lene carbonate(PC) and propylene glycol(PG) from propylene oxide( PO), carbon dioxide and methanol as the starting materials was investigated. The catalyst adopted here was a mixture of tetrabutyl ammonium bromide and sodium methoxide. It was found that un- der the reaction conditions of t = 150 ℃, p =3-4 MPa and 2 h, the PO conversion could reach 100%, the DMC, PC and the PG selectivities were 49. 7%, 42. 7% and 49. 8%, respectively, and the selectivity of by-products was below 10%.展开更多
Cu2O nanocubes and Cu nanoparticles were prepared by reducing Cu( Ⅱ ) salt with ethanol as the reducing agent and solvent in the presence of multidentate ligand poly(vinylpyrrolidone) (PVP) under different cond...Cu2O nanocubes and Cu nanoparticles were prepared by reducing Cu( Ⅱ ) salt with ethanol as the reducing agent and solvent in the presence of multidentate ligand poly(vinylpyrrolidone) (PVP) under different conditions. The morphologies and the crystalline structures of the products were characterized by using scanning electron microscopy (SEM), transmission electron microscopy(TEM), selected-area electron diffraction( SAED), and powder X-ray diffraction(XRD). In particular, the influences of the solvothennal reaction temperature and alkalinity on the products were investigated. A lower temperature and a lower alkali concentration favor the formation of the Cu2O phase, whereas a higher temperature and a higher alkali concentration generally lead to the formation of the Cu phase.展开更多
1-(1-Adamantylamino)-2,4,6-trinitrobenzene (1) as a potential energy material has been synthesized in excellent yield and characterized by FT-IR, 1H NMR and single crystallographic methods, and is thermally stable...1-(1-Adamantylamino)-2,4,6-trinitrobenzene (1) as a potential energy material has been synthesized in excellent yield and characterized by FT-IR, 1H NMR and single crystallographic methods, and is thermally stable, decomposed in the range of 215- 72℃.展开更多
The hierarchically structured ZSM-5 monolith was prepared through transforming the skeletons of the macroporous silica gel into ZSM-5 by the steam-assisted conversion method. The morphology and monolithic shapes of ma...The hierarchically structured ZSM-5 monolith was prepared through transforming the skeletons of the macroporous silica gel into ZSM-5 by the steam-assisted conversion method. The morphology and monolithic shapes of macroporous silica gel were well preserved. The hierarchically structured ZSM-5 monolith exhibited the hierarchical porosity, with mesopores and macropores existing inside the macroporous silica gel, and micropores formed by the ZSM-5. The products have been characterized properly by using the XRD, SEM and N2 adsorption–desorption methods.展开更多
The erythrocyte-like magnesium hydroxide microspheres were synthesized in large scale through a simple solution phase route. The structures and morphologies of the products were analyzed by the X-ray diffractometer (...The erythrocyte-like magnesium hydroxide microspheres were synthesized in large scale through a simple solution phase route. The structures and morphologies of the products were analyzed by the X-ray diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM). The possible growth mechanism of the nanos-tructure was discussed briefly and the potential application was proposed.展开更多
A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization (HDS) of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxi...A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization (HDS) of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxidic precursors and sulfided active phases. The higher the Mo and Co, the lower the tetrahedrally coordinated molybdate, and the higher the polymolybdate. But the amount of polymolybdate decreased when CoMoO4 appeared. Cobalt-promoted polymolybdate was the precursor, and its relative content correlated well with the HDS selectivity. For sulfided catalysts, adding the cobalt-promoter led to local distortion-disorder of the MoS2 structure and the formation of a CoMoS phase. This method can provide important information for designing new industrial selective-HDS catalvsts.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.20671011,20331010,90406002and90406024)the 111 Project(No.B07012)the Key Laboratory of Structural Chemistry Foundation(No.060017).
文摘A novel flower-like hydrated magnesium carbonate hydroxide, Mg5 (CO3 )4 (OH)2·4H2O, with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use of template or organic surfactant. Reaction time has an important effect on the final morphology of the product. The micro-structure and morphology of Mg5 (CO3)4 (OH)2·4H2O were characterized by means of X-ray diffractometry (XRD), fieldemission scanning electron microscopy(FE-SEM). Brunauer-Emmett-Teller(BET) surface areas of the samples were also measured. The probable formation mechanism of flower-like micro-structure was discussed. It was found that Mg5 (CO3)4( OH)2·4H2O with flower-like micro-structure was a novel and efficient catalyst for the synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol.
文摘The one-pot synthesis of dimethyl carbonate(DMC) with co-production of propy-lene carbonate(PC) and propylene glycol(PG) from propylene oxide( PO), carbon dioxide and methanol as the starting materials was investigated. The catalyst adopted here was a mixture of tetrabutyl ammonium bromide and sodium methoxide. It was found that un- der the reaction conditions of t = 150 ℃, p =3-4 MPa and 2 h, the PO conversion could reach 100%, the DMC, PC and the PG selectivities were 49. 7%, 42. 7% and 49. 8%, respectively, and the selectivity of by-products was below 10%.
基金Supported by the National Natural Science Foundation of China(Nos. 20331010 and 90406002) and Specialized ResearchFund for the Doctoral Program of Higher Education(No. 20030007014).
文摘Cu2O nanocubes and Cu nanoparticles were prepared by reducing Cu( Ⅱ ) salt with ethanol as the reducing agent and solvent in the presence of multidentate ligand poly(vinylpyrrolidone) (PVP) under different conditions. The morphologies and the crystalline structures of the products were characterized by using scanning electron microscopy (SEM), transmission electron microscopy(TEM), selected-area electron diffraction( SAED), and powder X-ray diffraction(XRD). In particular, the influences of the solvothennal reaction temperature and alkalinity on the products were investigated. A lower temperature and a lower alkali concentration favor the formation of the Cu2O phase, whereas a higher temperature and a higher alkali concentration generally lead to the formation of the Cu phase.
基金the Natural Science Fund Council of China(Nos.20671011 and 20731002)the 111 Project(B07012),Key Laboratory of Structural Chemistry Foundation(No.060017)+1 种基金Excellent Young Scholars Research Fund of Beijing Institute of Technology(No.2006Y0715)Basic Research Fund of Beijing Institute of Technology(Nos.20060742022 and 20070742010).
文摘1-(1-Adamantylamino)-2,4,6-trinitrobenzene (1) as a potential energy material has been synthesized in excellent yield and characterized by FT-IR, 1H NMR and single crystallographic methods, and is thermally stable, decomposed in the range of 215- 72℃.
基金the founding of the State Key Project(Nos2006CB202506 and 2007BAE43B01)the State Key Laboratory of Catalytic Material and Reaction Engineering(RIPP,SINOPEC)
文摘The hierarchically structured ZSM-5 monolith was prepared through transforming the skeletons of the macroporous silica gel into ZSM-5 by the steam-assisted conversion method. The morphology and monolithic shapes of macroporous silica gel were well preserved. The hierarchically structured ZSM-5 monolith exhibited the hierarchical porosity, with mesopores and macropores existing inside the macroporous silica gel, and micropores formed by the ZSM-5. The products have been characterized properly by using the XRD, SEM and N2 adsorption–desorption methods.
基金Sponsored by the National Natural Science Foundation of China (20373004)Program for New Century Excellent Talentsin University (NCET)as well as by Engineering Research Institute,Peking University (ERIPKU)
文摘The erythrocyte-like magnesium hydroxide microspheres were synthesized in large scale through a simple solution phase route. The structures and morphologies of the products were analyzed by the X-ray diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM). The possible growth mechanism of the nanos-tructure was discussed briefly and the potential application was proposed.
基金funding of the State Key Project (Nos. 2012CB224802 and 2012BAE05B03)the SINOPEC Project (No. 111015)
文摘A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization (HDS) of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxidic precursors and sulfided active phases. The higher the Mo and Co, the lower the tetrahedrally coordinated molybdate, and the higher the polymolybdate. But the amount of polymolybdate decreased when CoMoO4 appeared. Cobalt-promoted polymolybdate was the precursor, and its relative content correlated well with the HDS selectivity. For sulfided catalysts, adding the cobalt-promoter led to local distortion-disorder of the MoS2 structure and the formation of a CoMoS phase. This method can provide important information for designing new industrial selective-HDS catalvsts.