Theoretical Investigation on Interaction between Guanine and Luteolin

The interacting patterns of the luteolin and guanine have been investigated by using the density functional theory B3LYP method with 6-31＋G＊ basis set. Eighteen stable structures for the luteolin-guanine complexes have been found respectively. The results indicate that the complexes are mainly stabilized by the hydrogen bonding interactions. Meanwhile, both the number and strength of hydrogen bond play important roles in determining the stability of the complexes which can form two or more hydrogen bonds. Theories of atoms in molecules and natural bond orbital have also been utilized to investigate the hydrogen bonds involved in all the systems. The interaction energies of all the complexes which were corrected by basis set superposition error are 6.04-56.94 kJ/mol. The calculation results indicate that there are strong hydrogen bonding interactions in the luteolin-guanine complexes. We compared the interaction between luteolin and four bases of DNA, and found luteolin-thymine was the strongest and luteolin-adenine was the weakest. The interaction between luteolin and DNA bases are all stronger than luteolin-water.     

NO供体型马蹄金素衍生物的合成及其初步的抗乙肝病毒活性

以马蹄金素[N-(N-苯甲酰基-L-苯丙氨酰基)-O-乙酰基-L-苯丙氨醇,MTS]为先导化合物,设计并合成了11个NO供体型马蹄金素衍生物,所有目标产物均未见文献报道,其结构经NMR,ESI-MS确认.以HepG2 2.2.15细胞为乙肝病毒载体,对合成的马蹄金素衍生物进行了抗乙肝病毒活性测试.结果表明,在测试浓度范围内,化合物6d,6e,6g具有抗HBV活性,其半数抑制浓度分别为6.88,37.51,11.07μmol/L.其中,化合物6d和6g的半数抑制浓度优于MTS(11.16μmol/L),且具有较高的抑制率,具有进一步研究开发的价值.     

Wet-spinning of Regenerated Silk Fiber fromAqueous Silk Fibroin Solutions: Influence ofCalcium Ion Addition in Spinning Dope on thePerformance of Regenerated Silk Fiber简

Ca（II） ions are added in the spinning dope to adjust the solidification rate of regenerated silk fibroin （RSF） solution during the wet-spinning process since Ca（II） ions are proved to be favorable to maintain the stable silk fibroin network in our previous work. The results show that when Ca（II）/RSF ratios are 1/50 and 1/20, the resulted RSF fibers exhibit good performance with the breaking energy more than 70 kJ/kg. However, higher Ca（II）/RSF ratio （for example, 1/10） hinders the solidification of spinning dope and results in poor RSF fibers. These observations together with earlier papers from this laboratory confirm that to produce tough silk fibers the spinning conditions must allow sufficient time for the adjustment of silk fibroin molecular chains.     

Stacking-faults-free zinc blende GaAs/AlGaAs axial heterostructure nanowires during vapor-liquid-solid growth

Pure zinc blende structure GaAs/AlGaAs axial heterostructure nanowires (NWs) are grown by metal organic chemical vapor deposition on GaAs(111) B substrates using Au-catalyzed vapor-liquid-solid mechanism.Al adatom enhances the influence of diameters on NWs growth rate.NWs are grown mainly through the contributions from the direct impingement of the precursors onto the alloy droplets and not so much from adatom diffusion.The results indicate that the droplet acts as a catalyst rather than an adatom collector.     

互素作用下的不变块(英文)

令A,G为有限群且(|A|,|G|)=1.设A通过自同构作用在G上.令B是G的A-不变块.若B的每一个指标都是A-不变的,且B的亏群是循环群,则A中心化B的某一亏群.     

Diophantine方程nx~2+2~m=y~n(英文)

设n是大于3的奇数.本文运用Y.Bilu,G.Hanrot和P.M.Voutier关于Lehmer数本原素因子存在性的新近结果,证明了方程nx~2+2~m=y~n没有适合gcd(x,y)=1且m为奇数的正整数解(x,y,m).     

素数p在数域Q(u~(1/2),v~(1/2))上的素理想分解

运用局部域理论给出了奇素数p在数域K=Q(u~(1/2),v~(1/2))上的素理想分解形式,其中l是奇素数,u,v∈z~*,且u/vQ~l.     

Marcinkiewicz积分的一个双权有界不等式

研究带粗糙核的Marcinkiewicz积分μΩ的一个双权有界不等式,其中核函数Ω满足Grafakos和Stefanov引进的一类条件.作为应用,得到了μΩ的一个向量值不等式.     

IS/IT项目选择决策的灰色逼近理想解排序法

IS/IT项目选择决策是一个多属性决策问题.针对传统逼近理想解排序法(TOPSIS)在确定属性权重系数上的缺陷,并考虑到在实际IS/IT项目选择决策过程中部分决策信息的不足,提出了基于灰色TOPSIS改进算法.算法运用区间灰数表达指标权重和指标评价值,定义备择项目与正、负理想解的灰色关联度,依此计算各备则项目的贴近度并实现最终排序.仿真实例验证了该方法的合理和有效性.     

模糊子坡代数、模糊等价关系及模糊同余关系的序方面

证明了坡代数(X,+,*)上所有模糊子坡代数构成的集合(SI[0.1](X,+,*),≤),所有模糊理想构成的集合(Id[0.1](X,+,*),≤),所有模糊滤子构成的集合(Fil[0.1](X,+,*),≤)都是([0,1]x,≤)的子完备格,所有模糊等价关系构成的集合(Equ[0.1](X,+,*),≤),所有模...