Investigation of Highly Designable Dented Structures in HP Model with Hydrogen Bond Energy

Some highly designable protein structures have dented on the surface of their native structures, and are not full compactly folded. According to hydrophobic-polar （HP） model the most designable structures are full compactly folded. To investigate the designability of the dented structures, we introduce the hydrogen bond energy in the secondary structures by using the secondary-structure-favored HP model proposed by Ou-yang etc. The result shows that the average designability increases with the strength of the hydrogen bond. The designabilities of the structures with same dented shape increase exponentially with the number of secondary structure sites. The dented structures can have the highest designabilities for a certain value of hydrogen bond energy density.     

火灾对混凝土结构性能影响的研究

通过对比大量文献资料,分析了火灾高温对混凝土强度的影响,抗拉强度随温度的变化规律,以及不同的冷却方式对高温后混凝土强度的影响;分析了影响钢筋与混凝土高温粘结性能的因素及粘结性能随温度变化的趋势;总结了不同温度对不同类型钢筋抗拉强度的影响,并对今后的研究提出了一些建议.     

Iron-catalyzed benzylation of 1,3-dicarbonyl compounds by simple toluene derivatives

An iron-catalyzed oxidative C-C bond formation by the reactions of simple toluene derivatives with 1,3-dicarbonyl compounds is developed.A benzylic radical addition to a benzoylmethanato iron species is proposed for the transformation.     

NiB,Ni_2B,Ni_3B原子簇结构及成键特性的DFT研究

用ＤＦＴ方法对ＮｉＢ，Ｎｉ２Ｂ，Ｎｉ３Ｂ二重态和四重态两种多重度的各种可能构型进行高水平的量子化学计算，结果发现Ｎｉ，Ｂ原子所带电荷的正负与原子簇的组成和结构有关，存在较强Ｎｉ，Ｂ的相互作用，Ｎｉ－Ｂ键对ＮｉＢ，Ｎｉ２Ｂ，Ｎｉ３Ｂ分子的稳定性有很大贡献     

Low dipole moment large β electrooptic chromophores based on exocyclic double bond conjugated bridge

Novel low dipole moment (μ) and large first hyperpolarizability (β) electrooptic chromophores have been designed based on the special characteristic of reversed dipole moment in the excited state of exocyclic double bond (ECDB) conjugated bridge by the optimization of the substituted method, and their electronic and second-order nonlinear optical properties have been theoretically investigated by employing the AM1/FF and ZINDO/S-CI approaches. By extending the conjugation length and optimizing the donor/acceptor strength, the oscillator strength of the excited transition that contributes to the molecular nonlinearity can be further enhanced. The designed chromophores possess a larger figure of merit (FOM) than that of 4-N,N-dimethylamino-4′-nitrostilbene (DANS), and lower (<5 D) ground state dipole moment.     

型钢-混凝土粘结机理的探讨

对型钢混凝土结构(SRC结构)中型钢-混凝土的粘结机理及影响粘结性能的主要因素进行了分析和探讨,并从混凝土保护层开裂与否的角度根据粘结力的扩散原理,提出了一种型钢-混凝土粘结强度的计算方法,可为型钢混凝土结构中型钢-混凝土粘结性能的研究及实际设计中粘结强度的计算提供参考.     

SF6的单取代和二取代物中^2JFF的半经验计算

运用最大键级杂化轨道这一计算方法，计算并拟合得到单取代和二取代的ＳＦ６衍生物中＾２ＪＦＦ的具体计算公式，由新公式得到的计算值与实验值基本吻合。     

Research progresses of artificial nucleic acid cleavage agents

Artificial nucleic acid cleavage agents have attracted close attention because they play important roles in biochemistry and molecular biology. According to the cleavage mechanism of nucleic acid, they are divided into three types, namely free radical, phosphodiester bond hydrolysis and elimination cleavage agents. In this review, a series of cleavage agents, including the site- and sequence-specific ones, are illustrated, and some suggestions for the future researches in this field are also put forward.     

Heath-Jarrow-Morton模型的二叉树解

对HJM模型的基本结构进行了研究，将二叉树应用于HJM单因素模型对债券进行数值计算，并且对二叉树下的债券价格与普通利率贴现的价格进行了比较。     

利用二酰亚胺选择性还原C=C双键

在Ｃ＝Ｎ、Ｃ≡Ｎ存在下，利用二酰亚胺将环丙基化合物（１）和（３）中的Ｃ＝Ｃ双键选择性还原，区域化学选择性为１００％，产率约为８０％。