一类新型非线性光学材料——二苯甲酮衍生物的合成及性能研究

为寻求新型、高效、优质倍频材料,我们合成了一类新型二苯甲酮类化合物,并对其红外、紫外、光声光谱及倍频性能进行了系列研究,发现二苯甲酮类化合物具有较强的倍频效率和较短的截止吸收波长,有着广泛的应用前景。     

非紧区域上算子值再生核的Mercer定理

多任务学习已经成为机器学习领域一个热门的课题.算子值再生核理论是多任务学习的重要数学基础.本文的主要工作是建立了非紧区域上算子值再生核的Mercer定理,从而将传统的紧区域上的再生核Hilbert空间理论推广到非紧区域上.     

THE RELATION BETWEEN BAND STRUCTURE AND SUPERCONDUCTING TRANSITION TEMPERATURE IN SOME MIXED ALKALI-METAL DOPED C_(60)

The electronic band stucturec of crystalline N Na2RbC60 and Na2CsC60are examined using the three-dimensional crystal orbital method. Our calculation results reveal that ground states of all these three alkali-metal doped fulle.rides from a metalic conducting phase with a rather narrow molecular crystal-like band-stucture and a high density of state near the. fermi-level, which indicate a very high Tc for this newly found molecular superconductors. A monotonic relationship is found between our calculated band dispersion,Fermi-level density of state, and the experimental transition temperature Tc,which is in exceuentt agre.emet with the prediction of the. BCS model.