Graphene, a new two-dimensional carbon material, is a rising star of physics, chemistry and materials science. In this work, we report the recent experimental researches on the Raman spectra and the temperature-depend...Graphene, a new two-dimensional carbon material, is a rising star of physics, chemistry and materials science. In this work, we report the recent experimental researches on the Raman spectra and the temperature-dependent features of graphenes and car- bon nanoscrolls, which are evolved from graphene and have an open tubular structure. The layer-dependent Raman enhancing characteristics of n-layer graphenes for crystal violet, and the thickness-dependent morphologies of gold on n-layer graphenes are also systematically investigated. Meanwhile, the aggregations of ferromagnetic and paramagnetic atoms at edges of gra- phenes and graphite are observed and the mechanisms are discussed.展开更多
We simulated the heat transfer phenomena of the heating module that is primarily based on the radiant energy in the near-infra-red(NIR) domain.In the module,the power emitted by the lamp filament is distributed to the...We simulated the heat transfer phenomena of the heating module that is primarily based on the radiant energy in the near-infra-red(NIR) domain.In the module,the power emitted by the lamp filament is distributed to the lamp glass,reflector,and the target medium,which are cooled by an air flow.The radiant heat transfer is simulated by using the ray-tracing scheme,in which the spectral characteristics of the emission and the materials are incorporated.The heat transport from the lamp glass to the cooling air is analyzed by using the finite volume method.As the lamp-filament temperature rises in the range of 3000-3400K,the NIR radiant power on the target medium increases.However,the lamp-glass temperature also rises,and the proportion of the NIR power to the entire radiation has a peak in the temperature range.The spectral distributions of the absorbed energies in all the components in the module are highly non-uniform,and a monochromatic model of the radiant heat transfer may result in a significant discrepancy.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 10774032, 90921001, 50825206)
文摘Graphene, a new two-dimensional carbon material, is a rising star of physics, chemistry and materials science. In this work, we report the recent experimental researches on the Raman spectra and the temperature-dependent features of graphenes and car- bon nanoscrolls, which are evolved from graphene and have an open tubular structure. The layer-dependent Raman enhancing characteristics of n-layer graphenes for crystal violet, and the thickness-dependent morphologies of gold on n-layer graphenes are also systematically investigated. Meanwhile, the aggregations of ferromagnetic and paramagnetic atoms at edges of gra- phenes and graphite are observed and the mechanisms are discussed.
基金supported by the Korea Research Foundation Grant funded by the Korean Government(MOEHRD,Basic ResearchPromotion Fund)(KRF-2008-331-D00076)
文摘We simulated the heat transfer phenomena of the heating module that is primarily based on the radiant energy in the near-infra-red(NIR) domain.In the module,the power emitted by the lamp filament is distributed to the lamp glass,reflector,and the target medium,which are cooled by an air flow.The radiant heat transfer is simulated by using the ray-tracing scheme,in which the spectral characteristics of the emission and the materials are incorporated.The heat transport from the lamp glass to the cooling air is analyzed by using the finite volume method.As the lamp-filament temperature rises in the range of 3000-3400K,the NIR radiant power on the target medium increases.However,the lamp-glass temperature also rises,and the proportion of the NIR power to the entire radiation has a peak in the temperature range.The spectral distributions of the absorbed energies in all the components in the module are highly non-uniform,and a monochromatic model of the radiant heat transfer may result in a significant discrepancy.
