实验制备了三种改性煤沥青,分别是:用苯丙烯醛(CMA)改性的沥青,用对甲苯磺酸(PTS)改性的沥青,以及用上述这两种物质混合改性的沥青。通过红外光谱及热分析对原料沥青及改性沥青进行了表征。对这四种沥青在不同温度下进行炭化,并对其炭...实验制备了三种改性煤沥青,分别是:用苯丙烯醛(CMA)改性的沥青,用对甲苯磺酸(PTS)改性的沥青,以及用上述这两种物质混合改性的沥青。通过红外光谱及热分析对原料沥青及改性沥青进行了表征。对这四种沥青在不同温度下进行炭化,并对其炭化产物进行红外光谱和偏光表征。结果表明,通过改性,煤沥青的性能和炭化行为发生较大变化。在这四种沥青中,用CMA和PTS混合物改性的沥青,炭化产率高于仅用其中一种物质改性的沥青的炭化产率。另外,100 g煤沥青用7 g PTS和10 mL CMA的混合物改性的产物在800oC的炭化产率比原料沥青增加5.08%。并且在相同条件下,与其他三种沥青相比,其能够得到更多的中间相碳微球。红外光谱结果表明,在改性沥青热解过程中,CMA在300℃以下挥发,并且甲基和亚甲基随着温度的升高逐渐消失。展开更多
Parent coal tar pitch(CTP)was modified with boric acid(BA),cinnamaldehyde(CMA)and the mixture of BA and CMA,respectively.The parent CTP and three modified CTPs were characterized by elemental analysis,thermogravimetri...Parent coal tar pitch(CTP)was modified with boric acid(BA),cinnamaldehyde(CMA)and the mixture of BA and CMA,respectively.The parent CTP and three modified CTPs were characterized by elemental analysis,thermogravimetric analysis,Fourier transform infrared(FT-IR)spectroscopy and scanning electron microscopy.The four samples were carbonized at different temperatures and resultant carbonized products were characterized by FT-IR spectroscopy,X-ray diffraction and polarized-light microscopy.The results show that the morphologies and carbonization behaviors of the parent CTP and modified CTPs are quite different.The carbonization yield of the CTP modified with the mixture of BA and CMA is higher than that of CTP modified with BA or CMA only.In addition,the modification of CTP with 7 g of BA and 10 ml of CMA results in an increase in carbonization yield by5.64%.During the pyrolysis of modified CTPs,the dehydration of BA or the distillation of CMA occurs at the temperature lower than 300°C,and methyl and methylene groups of the modified CTPs disappear gradually as temperature rises.Furthermore,the modification of CTP by the mixture of BA and CMA results in more intensive mesophase spheres than other modified CTPs,and the modified CTP is easier to be carbonized to form graphitic carbon.展开更多
We investigate the heat generation Q in a quantum dot （QD）, coupled to a normal metal and a superconduc- tor, without electric bias voltage. It is found that Q is quite sensitive to the lead temperatures TL,R and th...We investigate the heat generation Q in a quantum dot （QD）, coupled to a normal metal and a superconduc- tor, without electric bias voltage. It is found that Q is quite sensitive to the lead temperatures TL,R and the superconductor gap magnitude △. At TL,R 〈〈 ω0 （ω0 is the phonon frequency）, the superconductor affects Q only at △ 〈ω0, and the maximum magnitude of negative Q appears at some △ slightly smaller than ω0. At elevated lead temperature, contribution to O from the superconductor arises at △, ranging from less than to much larger than wo. However, the peak value of Q is several times smaller than that in the case of TL,R 〈〈ω0. Interchanging lead temperatures TL and TR leads to quite different Q behaviors, while this makes no difference for a normal-metal quantum-dot-normal-metal system, and the QD can be cooled much more efficiently when the superconductor is colder.展开更多
基金Specialized Research Fund for the Doctoral Program of Higher Education(20096102120016)Innovation Foundation of China Aerospace Science and Technology(CASC200906,CASC201106)+1 种基金Supporting Program of China Aerospace Science and Technology(CASC201209)Foundation for Fundamental Research of Northw estern Polytechnical University(JC201030)~~
基金Natural Science Foundation of Shaanxi Province(2009GM6001-1)~~
文摘实验制备了三种改性煤沥青,分别是:用苯丙烯醛(CMA)改性的沥青,用对甲苯磺酸(PTS)改性的沥青,以及用上述这两种物质混合改性的沥青。通过红外光谱及热分析对原料沥青及改性沥青进行了表征。对这四种沥青在不同温度下进行炭化,并对其炭化产物进行红外光谱和偏光表征。结果表明,通过改性,煤沥青的性能和炭化行为发生较大变化。在这四种沥青中,用CMA和PTS混合物改性的沥青,炭化产率高于仅用其中一种物质改性的沥青的炭化产率。另外,100 g煤沥青用7 g PTS和10 mL CMA的混合物改性的产物在800oC的炭化产率比原料沥青增加5.08%。并且在相同条件下,与其他三种沥青相比,其能够得到更多的中间相碳微球。红外光谱结果表明,在改性沥青热解过程中,CMA在300℃以下挥发,并且甲基和亚甲基随着温度的升高逐渐消失。
基金Supported by the Natural Science Foundation of Shaanxi Province（2009GM6001-1） the Foundation for Fundamental Research of Northwestern Polytechnical University（JC201030）
文摘Parent coal tar pitch(CTP)was modified with boric acid(BA),cinnamaldehyde(CMA)and the mixture of BA and CMA,respectively.The parent CTP and three modified CTPs were characterized by elemental analysis,thermogravimetric analysis,Fourier transform infrared(FT-IR)spectroscopy and scanning electron microscopy.The four samples were carbonized at different temperatures and resultant carbonized products were characterized by FT-IR spectroscopy,X-ray diffraction and polarized-light microscopy.The results show that the morphologies and carbonization behaviors of the parent CTP and modified CTPs are quite different.The carbonization yield of the CTP modified with the mixture of BA and CMA is higher than that of CTP modified with BA or CMA only.In addition,the modification of CTP with 7 g of BA and 10 ml of CMA results in an increase in carbonization yield by5.64%.During the pyrolysis of modified CTPs,the dehydration of BA or the distillation of CMA occurs at the temperature lower than 300°C,and methyl and methylene groups of the modified CTPs disappear gradually as temperature rises.Furthermore,the modification of CTP by the mixture of BA and CMA results in more intensive mesophase spheres than other modified CTPs,and the modified CTP is easier to be carbonized to form graphitic carbon.
基金Supported by the National Natural Science Foundation of China under Grant No 11164011
文摘We investigate the heat generation Q in a quantum dot （QD）, coupled to a normal metal and a superconduc- tor, without electric bias voltage. It is found that Q is quite sensitive to the lead temperatures TL,R and the superconductor gap magnitude △. At TL,R 〈〈 ω0 （ω0 is the phonon frequency）, the superconductor affects Q only at △ 〈ω0, and the maximum magnitude of negative Q appears at some △ slightly smaller than ω0. At elevated lead temperature, contribution to O from the superconductor arises at △, ranging from less than to much larger than wo. However, the peak value of Q is several times smaller than that in the case of TL,R 〈〈ω0. Interchanging lead temperatures TL and TR leads to quite different Q behaviors, while this makes no difference for a normal-metal quantum-dot-normal-metal system, and the QD can be cooled much more efficiently when the superconductor is colder.
