Ultrafine particle (UFP)alumina has been prepared by supereritical fluid drying process of inorganic salt with organic solvent system, which is reported for the first time. UFP-alumina prepared from this system is fea...Ultrafine particle (UFP)alumina has been prepared by supereritical fluid drying process of inorganic salt with organic solvent system, which is reported for the first time. UFP-alumina prepared from this system is featured by its hish specific surface area, large pore volume, small perticle size and low bulk density.展开更多
Graphene,as star versatile materials having extraordinarily high electric conductivity,electron mobility,thermal conductivity,thermal stability,optical transparency,and mechanical strength,has attracted much attention...Graphene,as star versatile materials having extraordinarily high electric conductivity,electron mobility,thermal conductivity,thermal stability,optical transparency,and mechanical strength,has attracted much attention from scientists and engineers in the field of materials,chemistry,physics,energy,and environment in the last decade and achieved fruitful accomplishment.This review discusses preparation strategies,functionality,characterization,and applications for two dimensional nanosheet and quasi-onedimensional nanoribbon of graphene through direct exfoliation of graphite,chemical vapor deposition of hydrocarbon,laser-induced direct synthesis of graphene,laser etched graphene oxide in the dry state without the use of toxic reducing agent hydrazine,unzipping carbon nanotube,and polycondensation of polycyclic aromatics on the basis of 178 representative references mostly in 2015.The stabilization of graphene oxide prepared in chemical preparation in " top-down" is emphasized.Several vital classic methods of characterizing molecular structure,C/O ratio,defect,morphology,single-or few-layered( 2 to 10 layers) structure,porous and hollow structures,including Raman spectroscopy,AFM,SEM,TEM,STM,electron diffraction,X-ray diffraction,and X-ray photoelectron spectroscopy are systematically introduced.Because graphene possesses novel incomparable multifunctionalities,its versatile applications as novel conducting additives,reinforcing filler,separation membrane,sensor,anticorrosive coating,catalyst,electromagnetic shield,lubricant,and flexible electrode materials in electrochemical and electronic devices,including photovoltaic cells,supercapacitors,rechargeable batteries,sensors,field effect transistors,light emitting diodes,separation membranes,adsorbents and absorbents,catalysts,electro-optic modulator,terahertz emitter and detector,and semiconductors,have been mentioned.Especially in the aspect of both high performance and cost-effectiveness,graphene is expected to be even superior to the expensive carbon nanotubes.展开更多
Fifteen pyridine and substituted benzene diselenides,seleninic acids and seleninic anhydrides have been synthesized.Among them,4,4'-dipyridinediselenide,bis(2,4-dimethoxyphenyl)diselenide, 2,4-dimethoxyphenyl sele...Fifteen pyridine and substituted benzene diselenides,seleninic acids and seleninic anhydrides have been synthesized.Among them,4,4'-dipyridinediselenide,bis(2,4-dimethoxyphenyl)diselenide, 2,4-dimethoxyphenyl seleninic acid,2-pyridineseleninic acid,2-pyridineseleninic anhydride,4-pyridine- seleninic anhydride,2-nitrophenyl seleninic anhydride and 4-nitrophenyl seleninic anhydride were new compounds.Their regioselective oxidation or dehydrogenation of β-pinene,3β-benzoyloxycholest- 5-ene and androstan-3-one have been studied and compared.2-Pyridineseleninic anhydride is a more efficient oxidant than the others;most of the substituted benzeneseleno derivatives did not give the expected products.展开更多
This paper reviews the recent progress in the synthesis and application of pillared transition metal oxides during the last decade, mainly concerning the synthetic methods, structures, physical properties and catalyti...This paper reviews the recent progress in the synthesis and application of pillared transition metal oxides during the last decade, mainly concerning the synthetic methods, structures, physical properties and catalytic appli-cations of the layered transition metal oxides pillared by inorganic oxides. The factors and their affecting regularity in the process of preparation, and some important results ob-tained in the catalytic application studies are summarized. Finally, a prospect on the potential new directions in this research area is also presented.展开更多
文摘Ultrafine particle (UFP)alumina has been prepared by supereritical fluid drying process of inorganic salt with organic solvent system, which is reported for the first time. UFP-alumina prepared from this system is featured by its hish specific surface area, large pore volume, small perticle size and low bulk density.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51273148)the Foundation of State Key Laboratory of Pollution Control and Resource Reuse(Tongji University),China(Grant No.PCRRY14003)
文摘Graphene,as star versatile materials having extraordinarily high electric conductivity,electron mobility,thermal conductivity,thermal stability,optical transparency,and mechanical strength,has attracted much attention from scientists and engineers in the field of materials,chemistry,physics,energy,and environment in the last decade and achieved fruitful accomplishment.This review discusses preparation strategies,functionality,characterization,and applications for two dimensional nanosheet and quasi-onedimensional nanoribbon of graphene through direct exfoliation of graphite,chemical vapor deposition of hydrocarbon,laser-induced direct synthesis of graphene,laser etched graphene oxide in the dry state without the use of toxic reducing agent hydrazine,unzipping carbon nanotube,and polycondensation of polycyclic aromatics on the basis of 178 representative references mostly in 2015.The stabilization of graphene oxide prepared in chemical preparation in " top-down" is emphasized.Several vital classic methods of characterizing molecular structure,C/O ratio,defect,morphology,single-or few-layered( 2 to 10 layers) structure,porous and hollow structures,including Raman spectroscopy,AFM,SEM,TEM,STM,electron diffraction,X-ray diffraction,and X-ray photoelectron spectroscopy are systematically introduced.Because graphene possesses novel incomparable multifunctionalities,its versatile applications as novel conducting additives,reinforcing filler,separation membrane,sensor,anticorrosive coating,catalyst,electromagnetic shield,lubricant,and flexible electrode materials in electrochemical and electronic devices,including photovoltaic cells,supercapacitors,rechargeable batteries,sensors,field effect transistors,light emitting diodes,separation membranes,adsorbents and absorbents,catalysts,electro-optic modulator,terahertz emitter and detector,and semiconductors,have been mentioned.Especially in the aspect of both high performance and cost-effectiveness,graphene is expected to be even superior to the expensive carbon nanotubes.
文摘Fifteen pyridine and substituted benzene diselenides,seleninic acids and seleninic anhydrides have been synthesized.Among them,4,4'-dipyridinediselenide,bis(2,4-dimethoxyphenyl)diselenide, 2,4-dimethoxyphenyl seleninic acid,2-pyridineseleninic acid,2-pyridineseleninic anhydride,4-pyridine- seleninic anhydride,2-nitrophenyl seleninic anhydride and 4-nitrophenyl seleninic anhydride were new compounds.Their regioselective oxidation or dehydrogenation of β-pinene,3β-benzoyloxycholest- 5-ene and androstan-3-one have been studied and compared.2-Pyridineseleninic anhydride is a more efficient oxidant than the others;most of the substituted benzeneseleno derivatives did not give the expected products.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 29903005 and 29573108) and the Modern Analysis Foundation of Nanjing University.
文摘This paper reviews the recent progress in the synthesis and application of pillared transition metal oxides during the last decade, mainly concerning the synthetic methods, structures, physical properties and catalytic appli-cations of the layered transition metal oxides pillared by inorganic oxides. The factors and their affecting regularity in the process of preparation, and some important results ob-tained in the catalytic application studies are summarized. Finally, a prospect on the potential new directions in this research area is also presented.
