[Ru(bpy)2L]2+、 [Ru(phen)2L]2+(L=pytp,pztp)电子结构与抗癌活性研究

对配合物[Ru(bpy)2L]2+、[Ru(phen)2L]2+(L=pytp,pztp),用密度泛函(DFT)法,在B3LYP/LanL2DZ水平上进行理论计算研究.探讨了配合物的电子结构与其抗癌活性的关系,主配体上N原子的增加有利于配合物与DNA的作用,增加配合物的抗癌活性.计算结果显示,对于配合物I～IV,其LUMO轨道能量次序为εI>εII和εIII>εIV;其LUMO的电子云主要分布在主配体上,且分布的含量有I相似文献   

基于评价函数的极紫外多层膜反射式起偏器和检偏器设计

 基于三种不同评价函数,利用全局优化算法设计了极紫外波段高性能反射式多层膜偏振元件。通过比对不同评价函数的设计结果,分析了评价函数、工作角度及膜层数对反射式多层膜偏振片性能的影响,确定了极紫外多层膜反射式偏振片设计的角度选择、膜层数选择及评价函数选择标准。为解决传统的单一性能优化造成的偏振度损失的问题,构造了偏振比对数结合反射率的评价函数,该方法设计的偏振元件性能优于传统优化方法设计的结果。     

磁控溅射制备横向梯度分布的Mo/Si周期多层膜

 采用磁控溅射方法在Si基板上镀制了横向梯度分布的Mo/Si周期多层膜。以X射线掠入射反射测量了横向梯度多层膜的膜系结构,在基板65 mm长度范围内,多层膜周期从8.21 nm线性减小到6.57 nm,周期梯度为0.03 nm/mm。国家同步辐射实验室反射率计的反射率测试结果表明：该横向梯度分布周期多层膜上不同位置,能反射在13.3~15.9 nm波段范围内不同波长的极紫外光,反射率为60%~65%。     

二维NOESY核磁共振波谱结合全原子分子动力学模拟研究肌肽在水溶液中的构象变化

采用二维NOESY核磁共振波谱结合全原子分子动力学模拟研究了肌肽在水溶液中的构象变化和相互作用. 以分子内距离、回转半径、RMSD以及溶剂可接触表面积等性质进行表征. 分子动力学模拟显示肌肽分子在水溶液中表现出了较高的柔性,其构象在伸展、折叠之间互相转换,大部分情况下是以伸展的构象为主导的,而折叠构象较少. 二维NOESY核磁共振实验证实了模拟的结果,实验与理论得到很好的吻合.     

激光与生物组织选择性光热效应的两温度模型

考虑激光皮肤手术过程中色基与非色基组织对激光能量的差别吸收及二者界面处的能量传递发展了一种新的两温度传热模型。将模型应用于色素性及血管性疾病的激光治疗热过程,研究了激光脉冲宽度的影响。结果表明:两温度模型可以清晰地展示生物体内的选择性光热作用。脉冲宽度对于选择性光热效应有着非常重要的影响,过长的脉冲宽度会使能量传播到色基以外而使色基无法得到有效地加热,甚至会引起非色基组织的热损伤。     

亚飞秒啁啾Mo/Si多层膜反射镜的设计、制作与性能检测

针对利用高次谐波获取亚飞秒脉冲的实验需求,设计制备了啁啾为－2 800 as2的啁啾Mo/Si多层膜反射镜.数值计算表明,采用所设计的啁啾多层膜反射镜可以获得86 as的脉冲.通过直流磁控溅射方法实现了Mo/Si多层膜样品的制备.在合肥同步辐射上进行了多层膜反射率的测量,在所设计的工作波长内,多层膜的平均反射率为5.6±2.3%.在考虑最上层Si的氧化作用后,对测量曲线进行拟合,得到的反射率曲线和膜层厚度分布分别与测试曲线和设计结果相吻合.     

Circuit implementation and multiform intermittency in ahyper-chaotic model extended from Lorenz system

<正>This paper presents a non-autonomous hyper-chaotic system,which is formed by adding a periodic driving signal to a four-dimensional chaotic model extended from the Lorenz system.The resulting non-autonomous hyper-chaotic system can display any dynamic behaviour among the periodic orbits,intermittency,chaos and hyper-chaos by controlling the frequency of the periodic signal.The phenomenon has been well demonstrated by numerical simulations,bifurcation analysis and electronic circuit realization.Moreover,the system is concrete evidence for the presence of Pomeau-Manneville Type-Ⅰintermittency and crisis-induced intermittency.The emergence of a different type of intermittency is similarly subjected to the frequency of periodic forcing.By statistical analysis,power scaling laws consisting in different intermittency are obtained for the lifetime in the laminar state between burst states.     

A novel chaotic system with one source and two saddle-foci in Hopfield neural networks

This paper presents the finding of a novel chaotic system with one source and two saddle-foci in a simple three-dimensional (3D) autonomous continuous time Hopfield neural network. In particular, the system with one source and two saddle-foci has a chaotic attractor and a periodic attractor with different initial points, which has rarely been reported in 3D autonomous systems. The complex dynamical behaviours of the system are further investigated by means of a Lyapunov exponent spectrum, phase portraits and bifurcation analysis. By virtue of a result of horseshoe theory in dynamical systems, this paper presents rigorous computer-assisted verifications for the existence of a horseshoe in the system for a certain parameter.     

苯并咪唑/苯并噻唑类T315I突变型Abl抑制剂的结合机理和分子设计

Despite the efficacy of imatinib therapy in chronic myelogenous leukemia, the development of drug-resistant Abl mutants, especially the most difficult overcoming T315I mutant, makes the search for new Abl T315I inhibitors a very interesting challenge in medicinal chemistry. In this work, a multistep computational framework combining the three dimensional quantitative structure-activity relationship (3D-QSAR), molecular docking, molecular dynamics (MD) simulation and binding free energy calculation, was performed to explore the structural requirements for the Abl T315I activities of benzimidazole/benzothiazole derivatives and the binding mechanism between the inhibitors and Abl T315I. The established 3D-QSAR models exhibited satisfactory internal and external predictability. Docking study elucidated the comformations of compounds and the key amino acid residues at the binding pocket, which were confirmed by MD simulation. The binding free energies correlated well with the experimental activities. The MM-GBSA energy decomposition revealed that the van der Waals interaction was the major driving force for the interaction between the ligands and Abl T315I. The hydrogen bond interactions between the inhibitors and Met318 also played an important role in stablizing the binding of compounds to Abl T315I. Finally, four new compounds with rather high Abl T315I activities were designed and presented to experimenters for reference.     

小波变换表征多层膜氧化层、界面层和膜厚漂移

用小波变换的方法分析了纳米多层膜的X射线掠入射反射率测试曲线.从小波变换的自相关函数峰位和峰强度信息中得到了常规曲线拟合方法难以表征的含有氧化层、界面层或厚度漂移的多层膜结构,利用其作为多层膜的初始结构再进行常规的曲线拟合,可实现多层膜结构精确表征的目的.研究成功地鉴别出钒单层膜的表面存在约3 nm厚的氧化层,分析得到Mo/Si多层膜的界面纯粗糙度约0.42 nm,表明在Ni/C多层膜中接近表面和基底的膜层存在大于5%的厚度漂移.