Graphitized carbon foams(GFms)were prepared using mesophase pitch(MP)as a raw material by foaming(450℃),pre-oxidation(320℃),carbonization(1000℃)and graphitization(2800℃).The differences in structure and properties...Graphitized carbon foams(GFms)were prepared using mesophase pitch(MP)as a raw material by foaming(450℃),pre-oxidation(320℃),carbonization(1000℃)and graphitization(2800℃).The differences in structure and properties of GFms prepared from different MP precursors pretreated by ball milling or liquid phase extraction were investigated and compared,and semi-quantitative calculations were conducted on the Raman and FTIR spectra of samples at each preparation stage.Semi-quantitat-ive spectroscopic analysis provided detailed information on the structure and chemical composition changes of the MP and GFm de-rived from it.Combined with microscopic observations,the change from precursor to GFm was analyzed.The results showed that ball milling concentrated the distribution of aromatic molecules in the pitch,which contributed to uniform foaming to give a GFm with a uniform pore distribution and good properties.Liquid phase extraction helped remove light components while retaining large aromatics to form graphitic planes with the largest average size during post-treatment to produce a GFm with the highest degree of graphitization and the fewest open pores,giving the best compression resistance(2.47 MPa),the highest thermal conductivity(64.47 W/(m·K))and the lowest electrical resistance(13.02μΩ·m).Characterization combining semi-quantitative spectroscopic ana-lysis with microscopic observations allowed us to control the preparation of the MP-derived GFms.展开更多
就在几年前,曾经出版过一部专门研究悲剧对奥维德作品影响的专著:丹·科雷的《奥维德作品中的悲剧:戏剧、元戏剧以及一种文学体裁的转变》(Dan Curley,Tragedy in Ovid.Theater,Metatheater,and the Trans formation of a Genre)。...就在几年前,曾经出版过一部专门研究悲剧对奥维德作品影响的专著:丹·科雷的《奥维德作品中的悲剧:戏剧、元戏剧以及一种文学体裁的转变》(Dan Curley,Tragedy in Ovid.Theater,Metatheater,and the Trans formation of a Genre)。~②如果我说这部著作刚一出版便已经过时了,我并不是要对作者进行任何批评。他可能并不知道,在他的著作发售之际。展开更多
文摘Graphitized carbon foams(GFms)were prepared using mesophase pitch(MP)as a raw material by foaming(450℃),pre-oxidation(320℃),carbonization(1000℃)and graphitization(2800℃).The differences in structure and properties of GFms prepared from different MP precursors pretreated by ball milling or liquid phase extraction were investigated and compared,and semi-quantitative calculations were conducted on the Raman and FTIR spectra of samples at each preparation stage.Semi-quantitat-ive spectroscopic analysis provided detailed information on the structure and chemical composition changes of the MP and GFm de-rived from it.Combined with microscopic observations,the change from precursor to GFm was analyzed.The results showed that ball milling concentrated the distribution of aromatic molecules in the pitch,which contributed to uniform foaming to give a GFm with a uniform pore distribution and good properties.Liquid phase extraction helped remove light components while retaining large aromatics to form graphitic planes with the largest average size during post-treatment to produce a GFm with the highest degree of graphitization and the fewest open pores,giving the best compression resistance(2.47 MPa),the highest thermal conductivity(64.47 W/(m·K))and the lowest electrical resistance(13.02μΩ·m).Characterization combining semi-quantitative spectroscopic ana-lysis with microscopic observations allowed us to control the preparation of the MP-derived GFms.
文摘就在几年前,曾经出版过一部专门研究悲剧对奥维德作品影响的专著:丹·科雷的《奥维德作品中的悲剧:戏剧、元戏剧以及一种文学体裁的转变》(Dan Curley,Tragedy in Ovid.Theater,Metatheater,and the Trans formation of a Genre)。~②如果我说这部著作刚一出版便已经过时了,我并不是要对作者进行任何批评。他可能并不知道,在他的著作发售之际。
