The interaction of proteins with salt ions plays an important role in life activities.We used butyramide as a model molecule to investigate the interaction of protein backbones with cations.The experiment was performe...The interaction of proteins with salt ions plays an important role in life activities.We used butyramide as a model molecule to investigate the interaction of protein backbones with cations.The experiment was performed in an aqueous solution of metal chloride using UV Raman spectroscopy.It was found that well-hydrated metal cations(Ca^(2+),Mg^(2+))tend to bind to C=O in the amide bond,resulting in redistribution of the amide I band peaks.Specifically,the peak intensity ratio of 1655 cm^(-1)to 1610 cm^(-1)increases significantly with increasing concentrations.However,this phenomenon is not obviously observed in NaCl solution.Furthermore,we studied the effect of salt ions on the water structures.The addition of Ca^(2+)and Mg^(2+)is beneficial to the enhancement of the water signal at the 3400 cm^(-1)position,while the Na^(+)at the same concentration is not obvious.The results have shown that the interaction between cations and amides satisfies the following order:Ca^(2+)>Mg^(2+)>Na^(+),which conforms to the Hofmeister series.展开更多
We show that there is a quantum Sl_q(2) group symmetry in Hofstadter problem on square lattice.The cyclic representation of the quantum group is discussed and its application for computing the degeneracy density of th...We show that there is a quantum Sl_q(2) group symmetry in Hofstadter problem on square lattice.The cyclic representation of the quantum group is discussed and its application for computing the degeneracy density of the model is shown.展开更多
低音提琴出生于乐队,也在乐队中得到发展,它的出现使得乐队音响的低音更加出色。随着乐器本身的发展和配齐逐渐成熟,低音提琴开始渐渐成为一个独立的声部。霍夫迈斯特(Franz Anton Hoffmeister,1754—1812)所创作的第一低音提琴协奏曲,...低音提琴出生于乐队,也在乐队中得到发展,它的出现使得乐队音响的低音更加出色。随着乐器本身的发展和配齐逐渐成熟,低音提琴开始渐渐成为一个独立的声部。霍夫迈斯特(Franz Anton Hoffmeister,1754—1812)所创作的第一低音提琴协奏曲,整个乐曲如双音演奏,华彩片段演奏法等等,这些都为低音提琴演奏的演奏技法做出了很大的贡献。本文将分析作者的创作背景及作品的意义,并重点介绍该协奏曲第一乐章的曲式结构、调式调性和作品分析。展开更多
基金supported by the National Natural Science Foundation of China(No.62005108,No.62205134)the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(No.21KJB140008)the Graduate Research and Practice Innovation Program of Jiangsu Normal University(No.2021XKT1201,No.2021XKT1204).
文摘The interaction of proteins with salt ions plays an important role in life activities.We used butyramide as a model molecule to investigate the interaction of protein backbones with cations.The experiment was performed in an aqueous solution of metal chloride using UV Raman spectroscopy.It was found that well-hydrated metal cations(Ca^(2+),Mg^(2+))tend to bind to C=O in the amide bond,resulting in redistribution of the amide I band peaks.Specifically,the peak intensity ratio of 1655 cm^(-1)to 1610 cm^(-1)increases significantly with increasing concentrations.However,this phenomenon is not obviously observed in NaCl solution.Furthermore,we studied the effect of salt ions on the water structures.The addition of Ca^(2+)and Mg^(2+)is beneficial to the enhancement of the water signal at the 3400 cm^(-1)position,while the Na^(+)at the same concentration is not obvious.The results have shown that the interaction between cations and amides satisfies the following order:Ca^(2+)>Mg^(2+)>Na^(+),which conforms to the Hofmeister series.
文摘We show that there is a quantum Sl_q(2) group symmetry in Hofstadter problem on square lattice.The cyclic representation of the quantum group is discussed and its application for computing the degeneracy density of the model is shown.
文摘低音提琴出生于乐队,也在乐队中得到发展,它的出现使得乐队音响的低音更加出色。随着乐器本身的发展和配齐逐渐成熟,低音提琴开始渐渐成为一个独立的声部。霍夫迈斯特(Franz Anton Hoffmeister,1754—1812)所创作的第一低音提琴协奏曲,整个乐曲如双音演奏,华彩片段演奏法等等,这些都为低音提琴演奏的演奏技法做出了很大的贡献。本文将分析作者的创作背景及作品的意义,并重点介绍该协奏曲第一乐章的曲式结构、调式调性和作品分析。
