The second-order nonlinear optical （NLO） properties of 5,10,15-triphenylcorrole （TPC）, 5,10,15,20-tetraphenylporphyrin （TPP） and L-amino acid bridged bis-corroles 1,2,3 and 4 have been calculated by using TDHF/P...The second-order nonlinear optical （NLO） properties of 5,10,15-triphenylcorrole （TPC）, 5,10,15,20-tetraphenylporphyrin （TPP） and L-amino acid bridged bis-corroles 1,2,3 and 4 have been calculated by using TDHF/PM3 method based on the RHF/6-31G （TPC and TPP） or semiempirical PM3 （1, 2, 3, 4） optimized geometries. Calculation results showed TPC and TPP have C1 and D2h symmetry, respectively when N-H protons are localized on the nitrogen atoms. TPC is the second-order NLO active chromophore due to the cancellation of centrosymmetrical structure and its first hyperpolarizability β increases to 11.524×10^-30 esu. Under electrical dipole approximation, βvalues of bis-corroles 1, 2, 3 and 4 vary from 9.831×10^-30 to 14.221×10^-30 esu, and no much improvement in the first hyperpolarizability was observed as compared to TPC monomer.However, β values of bis-corroles 1, 2, 3 and 4 are improved by about 4 times as compared to their bis-porphyrin counterparts. The analysis of β components indicates that β of this kind of bis-corroles is mainly contributed from its radial component βr. With the variation of amino acid side chains, βHRS, β,βxyz, βr and βa of bis-corroles change remarkably. Chiral L-amino acid bridged bis-corroles 2, 3 and 4 have a right-handed helix structure, and their chiral component βxyz matches βxyz ∝ r^2 ζ/L^4 （helix parameters）, showing the second-order chiral NLO response of these bis-corroles could be described by one-electron helical model theory. It was found that the radial component βr of chiral helix bis-corroles also matches βr ∝ r^2 ζ/L^4.展开更多
对IPSec与NAT在包头封装和改写过程中存在冲突而产生的相互不兼容问题进行分析,在此基础上采用H3C Cloud Lab平台对IPSec野蛮模式实现NAT穿越的解决方案进行了仿真实验.针对NAPT环境与IPSec存在的冲突问题,提出了基于GRE over IPSec的...对IPSec与NAT在包头封装和改写过程中存在冲突而产生的相互不兼容问题进行分析,在此基础上采用H3C Cloud Lab平台对IPSec野蛮模式实现NAT穿越的解决方案进行了仿真实验.针对NAPT环境与IPSec存在的冲突问题,提出了基于GRE over IPSec的隧道嵌套技术解决方案并进行仿真实验,可以进一步满足NAT环境下部署IPSec的实际需求.展开更多
基金Supported by the NNSFC (20476034), Research Grants Council of Hongkong and SRF for ROCS, State Education Ministry
文摘The second-order nonlinear optical （NLO） properties of 5,10,15-triphenylcorrole （TPC）, 5,10,15,20-tetraphenylporphyrin （TPP） and L-amino acid bridged bis-corroles 1,2,3 and 4 have been calculated by using TDHF/PM3 method based on the RHF/6-31G （TPC and TPP） or semiempirical PM3 （1, 2, 3, 4） optimized geometries. Calculation results showed TPC and TPP have C1 and D2h symmetry, respectively when N-H protons are localized on the nitrogen atoms. TPC is the second-order NLO active chromophore due to the cancellation of centrosymmetrical structure and its first hyperpolarizability β increases to 11.524×10^-30 esu. Under electrical dipole approximation, βvalues of bis-corroles 1, 2, 3 and 4 vary from 9.831×10^-30 to 14.221×10^-30 esu, and no much improvement in the first hyperpolarizability was observed as compared to TPC monomer.However, β values of bis-corroles 1, 2, 3 and 4 are improved by about 4 times as compared to their bis-porphyrin counterparts. The analysis of β components indicates that β of this kind of bis-corroles is mainly contributed from its radial component βr. With the variation of amino acid side chains, βHRS, β,βxyz, βr and βa of bis-corroles change remarkably. Chiral L-amino acid bridged bis-corroles 2, 3 and 4 have a right-handed helix structure, and their chiral component βxyz matches βxyz ∝ r^2 ζ/L^4 （helix parameters）, showing the second-order chiral NLO response of these bis-corroles could be described by one-electron helical model theory. It was found that the radial component βr of chiral helix bis-corroles also matches βr ∝ r^2 ζ/L^4.
文摘对IPSec与NAT在包头封装和改写过程中存在冲突而产生的相互不兼容问题进行分析,在此基础上采用H3C Cloud Lab平台对IPSec野蛮模式实现NAT穿越的解决方案进行了仿真实验.针对NAPT环境与IPSec存在的冲突问题,提出了基于GRE over IPSec的隧道嵌套技术解决方案并进行仿真实验,可以进一步满足NAT环境下部署IPSec的实际需求.
