检索结果-南通市图书馆

x-ray absorption near-edge structure study on the configuration of Cu2＋/histidine complexes at different pH values

Chinese Physics B 2016年第4期25卷 474-478页

作者：于梅娟王宇徐伟 Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China

The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2＋/histidine （His） is a typical complex existing in many metalloproteins and plays an important role in lots of physiological functions. The three-dimensional （3D） structural configurations of Cu2＋/His complexes at different pH values （2.5, 6.5, and 8.5） are quantitatively determined by x-ray absorption near-edge structure （xANES）. Generally Cu2＋/His complex keeps an octahedral configuration consisting of oxygen atoms from water molecules and oxygen or nitrogen atoms from histidine molecules coordinated around Cu2＋. It is proved in this work that the oxygen atoms from water molecules, when increasing the pH value from acid to basic value, are gradually substituted by the Ocarboxy1, Nam, and Nim from hisitidine molecules. Furthermore, the symmetries of Cu2＋/His complexes at pH 6.5 and pH 8.5 are found to be lower than at pH 2.5.

关键词： x-ray absorption near-edge structure Cu2+/His pH values configuration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Interpretation of the pre-edge x-ray absorption fine structures in MnO

引用

Nuclear Science and Techniques 2003年第3期14卷 153-156页

作者： LI Shu-Jun, HU Rong, HU Tian-Dou, xIE Ya-Ning, ZHANG Jing, TAO Ye, WU Zi-Yu (Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, the Chinese Academy of Sciences, Beijing 100039 Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare, Via Enrico Fermi 40,1-00044 Frascati, Italy) Beijing Synchrotron Radiation Facility Institute of High Energy Physics the Chinese Academy of Sciences 北京 100039

The weak pre-edge features in the Mn AT-edge x-ray absorption near-edge structure (xANES) spectrum of manganese monoxide (MnO) were investigated by comparing experimental data with dipolar and quadrupolar cross-section calculations in the framework of multiple-scattering theory. We assign the first pre-edge feature to a direct quadrupolar transition from Is core state to 3d molecular orbitals of the central atom, e.g., the lowest in energy, due to the more effective attraction of the core hole. The second peak in this region arises unambiguously from the hybridization between p-orbitals of the central atom with higher-shell metal octahedral orbitals.

关键词： x-ray absorption fine structures x-ray absorption near-edge structure MnO

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：