Based on the mechanism of the effect of hydration on the heat stability of lysozyme and the theory of water molecule clusters, the effect of structure-changed water on heat stability of lysozyme has been studied. The ...Based on the mechanism of the effect of hydration on the heat stability of lysozyme and the theory of water molecule clusters, the effect of structure-changed water on heat stability of lysozyme has been studied. The results obtained by differential scanning calorimetry (DSC) showed that the thermal denaturation temperature of lysozyme had been elevated 8.47 K through hydration of lysozyme with processed water whose structure had been changed so it was called "structured water" compared to ordinary water. The reason is that structured water changed the dipole moment of water molecules and easily formed cyclic water hexamer or cage-like water hexamer, so that the interacting force of maintaining three-dimensional conformation of lysozyme could be reinforced.展开更多
In order to get more reliable electronic structures of proteins in aqueous solution, it is necessary to construct a potential of water molecules for protein’s electronic structure calculation. The lysine is a hydroph...In order to get more reliable electronic structures of proteins in aqueous solution, it is necessary to construct a potential of water molecules for protein’s electronic structure calculation. The lysine is a hydrophilic amino acid. It is positively charged (Lys+) in neutral water solution. The first-principles, all-electron, ab initio calcula-tions, based on the density functional theory, have been performed to construct such an equivalent potential of water molecules for lysine (Lys+). The process consists of three parts. First, the electronic structure of the cluster containing Lys+ and water molecules is calculated. By adjusting the positions of water molecules, the geometric structure of the cluster having minimum total energy is determined. Then, based on the structure, the electronic structure of Lys+ with the potential of water molecules is calculated using the self-consistent cluster-embedding (SCCE) method. Finally, the electronic structure of Lys+ with the potential of dipoles is calculated. The dipoles are adjusted so that the electronic structure of Lys+ with the potential of dipoles is close to that of water molecules. Thus the equivalent potential of water molecules for the electronic structure of lysine is obtained. The major effect of water molecules on lysine’s electronic structure is raising the occupied eigenvalues about 0.5032 eV, and broadening energy gap 89%. The effect of water molecules on the electronic structure of lysine can be simulated by dipoles potential.展开更多
在供水系统管理中,分区管理是进行管网运营、压力管理和漏损控制的有效工具,其构建方法直接影响分区效能的发挥程度。然而,大多数分区方法通常未能充分考虑管网的拓扑结构与水力状态之间的复杂相互作用,所得分区方案无法充分利用现有分...在供水系统管理中,分区管理是进行管网运营、压力管理和漏损控制的有效工具,其构建方法直接影响分区效能的发挥程度。然而,大多数分区方法通常未能充分考虑管网的拓扑结构与水力状态之间的复杂相互作用,所得分区方案无法充分利用现有分区设施,在实际工程应用中面临困难。鉴于此,提出了一种基于结构性深度聚类网络(Structural Deep Clustering Network,SDCN)的供水管网分区构建方法。使用SDCN有机融合管网拓扑结构和水力状态信息进行聚类分析,根据聚类结果以及管网计量设施实际情况,对孤立节点进行归类分析,提出聚类边界调整的有效计算方法,以形成最终分区方案。与两种经典的管网聚类方法相比,该方法具有更好的管网节点聚类精度,分区结果面向工程实际需求,可以为管网分区规划与建设提供有效的技术支撑。展开更多
文摘Based on the mechanism of the effect of hydration on the heat stability of lysozyme and the theory of water molecule clusters, the effect of structure-changed water on heat stability of lysozyme has been studied. The results obtained by differential scanning calorimetry (DSC) showed that the thermal denaturation temperature of lysozyme had been elevated 8.47 K through hydration of lysozyme with processed water whose structure had been changed so it was called "structured water" compared to ordinary water. The reason is that structured water changed the dipole moment of water molecules and easily formed cyclic water hexamer or cage-like water hexamer, so that the interacting force of maintaining three-dimensional conformation of lysozyme could be reinforced.
基金Supported by the National Natural Science Foundation of China (Grant No. 30470410)the Science and Technology Development Foundation of Shanghai (Grant No. 03JC14070)
文摘In order to get more reliable electronic structures of proteins in aqueous solution, it is necessary to construct a potential of water molecules for protein’s electronic structure calculation. The lysine is a hydrophilic amino acid. It is positively charged (Lys+) in neutral water solution. The first-principles, all-electron, ab initio calcula-tions, based on the density functional theory, have been performed to construct such an equivalent potential of water molecules for lysine (Lys+). The process consists of three parts. First, the electronic structure of the cluster containing Lys+ and water molecules is calculated. By adjusting the positions of water molecules, the geometric structure of the cluster having minimum total energy is determined. Then, based on the structure, the electronic structure of Lys+ with the potential of water molecules is calculated using the self-consistent cluster-embedding (SCCE) method. Finally, the electronic structure of Lys+ with the potential of dipoles is calculated. The dipoles are adjusted so that the electronic structure of Lys+ with the potential of dipoles is close to that of water molecules. Thus the equivalent potential of water molecules for the electronic structure of lysine is obtained. The major effect of water molecules on lysine’s electronic structure is raising the occupied eigenvalues about 0.5032 eV, and broadening energy gap 89%. The effect of water molecules on the electronic structure of lysine can be simulated by dipoles potential.
文摘在供水系统管理中,分区管理是进行管网运营、压力管理和漏损控制的有效工具,其构建方法直接影响分区效能的发挥程度。然而,大多数分区方法通常未能充分考虑管网的拓扑结构与水力状态之间的复杂相互作用,所得分区方案无法充分利用现有分区设施,在实际工程应用中面临困难。鉴于此,提出了一种基于结构性深度聚类网络(Structural Deep Clustering Network,SDCN)的供水管网分区构建方法。使用SDCN有机融合管网拓扑结构和水力状态信息进行聚类分析,根据聚类结果以及管网计量设施实际情况,对孤立节点进行归类分析,提出聚类边界调整的有效计算方法,以形成最终分区方案。与两种经典的管网聚类方法相比,该方法具有更好的管网节点聚类精度,分区结果面向工程实际需求,可以为管网分区规划与建设提供有效的技术支撑。
