This paper reports that the absorption spectra of H2O^＋ have been measured by tunable mid-infrared diode laser spectroscopy in the spectral range of 1100-1380 cm^-1. The H2O＋ ions are generated in an AC glow dischar...This paper reports that the absorption spectra of H2O^＋ have been measured by tunable mid-infrared diode laser spectroscopy in the spectral range of 1100-1380 cm^-1. The H2O＋ ions are generated in an AC glow discharge of the gaseous mixtures of H2O/He and detected with the velocity modulation technique. Forty new lines are assigned to the ν2 fundamental band of H2O^＋ （X^2B1）. The observed lines together with other data published previously are fitted to the standard effective Hamiltonian of an asymmetric top, yielding a set of improved rotational constants, spin-rotation constants and their quartic and sextic centrifugal distortion constants for the ν2=1 vibrational state of H2O＋.展开更多
目的建立在线监测注射用头孢唑林钠干燥过程中的水分含量测定方法。方法水分定量模型建模样品采以不同批次、不同干燥时间段五水头孢唑林钠原料为研究对象,结合干燥、引湿实验扩充样品水分范围,用积分球测定近红外漫反射光谱,并采用聚...目的建立在线监测注射用头孢唑林钠干燥过程中的水分含量测定方法。方法水分定量模型建模样品采以不同批次、不同干燥时间段五水头孢唑林钠原料为研究对象,结合干燥、引湿实验扩充样品水分范围,用积分球测定近红外漫反射光谱,并采用聚类分析挑选出建模光谱,光谱预处理方法为一阶导数+MSC法,谱段为7502~6499.2、5500.2~3 999.8 cm^(-1),回归方法偏最小二乘法。结果水分定量模型建模样品共计85个,水分含量质量分数为12.15%~16.41%,相关系数(coefficient of determination,R^2)为96.30,交叉验证均方差(root mean square error of cross validation,RMSECV)为0.181。外部验证样品52个,水分含量质量分数为13.28%~16.17%,外部验证均方差(root mean square error of predication,RMSEP)为0.149。模型专属性强,准确度、线性和精密度符合要求。结论建立的运用近红外监测注射用头孢唑林钠干燥过程的水分含量方法是可行的,为实现近红外在线干燥提供了实验基础。展开更多
Quasi-elastic neutron scattering(QENS) has many applications that are directly related to the development of highperformance functional materials and biological macromolecules, especially those containing some water. ...Quasi-elastic neutron scattering(QENS) has many applications that are directly related to the development of highperformance functional materials and biological macromolecules, especially those containing some water. The analysis method of QENS spectra data is important to obtain parameters that can explain the structure of materials and the dynamics of water. In this paper, we present a revised jump-diffusion and rotation-diffusion model(rJRM) used for QENS spectra data analysis. By the rJRM, the QENS spectra from a pure magnesium-silicate-hydrate(MSH) sample are fitted well for the Q range from 0.3 ^(-1) to 1.9 ^(-1) and temperatures from 210 K up to 280 K. The fitted parameters can be divided into two kinds. The first kind describes the structure of the MSH sample, including the ratio of immobile water(or bound water) C and the confining radius of mobile water a_0. The second kind describes the dynamics of confined water in pores contained in the MSH sample, including the translational diffusion coefficient Dt, the average translational residence timeτ0, the rotational diffusion coefficient D_r, and the mean squared displacement(MSD) u^2. The r JRM is a new practical method suitable to fit QENS spectra from porous materials, where hydrogen atoms appear in both solid and liquid phases.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10544002 and 10604019)
文摘This paper reports that the absorption spectra of H2O^＋ have been measured by tunable mid-infrared diode laser spectroscopy in the spectral range of 1100-1380 cm^-1. The H2O＋ ions are generated in an AC glow discharge of the gaseous mixtures of H2O/He and detected with the velocity modulation technique. Forty new lines are assigned to the ν2 fundamental band of H2O^＋ （X^2B1）. The observed lines together with other data published previously are fitted to the standard effective Hamiltonian of an asymmetric top, yielding a set of improved rotational constants, spin-rotation constants and their quartic and sextic centrifugal distortion constants for the ν2=1 vibrational state of H2O＋.
文摘目的建立在线监测注射用头孢唑林钠干燥过程中的水分含量测定方法。方法水分定量模型建模样品采以不同批次、不同干燥时间段五水头孢唑林钠原料为研究对象,结合干燥、引湿实验扩充样品水分范围,用积分球测定近红外漫反射光谱,并采用聚类分析挑选出建模光谱,光谱预处理方法为一阶导数+MSC法,谱段为7502~6499.2、5500.2~3 999.8 cm^(-1),回归方法偏最小二乘法。结果水分定量模型建模样品共计85个,水分含量质量分数为12.15%~16.41%,相关系数(coefficient of determination,R^2)为96.30,交叉验证均方差(root mean square error of cross validation,RMSECV)为0.181。外部验证样品52个,水分含量质量分数为13.28%~16.17%,外部验证均方差(root mean square error of predication,RMSEP)为0.149。模型专属性强,准确度、线性和精密度符合要求。结论建立的运用近红外监测注射用头孢唑林钠干燥过程的水分含量方法是可行的,为实现近红外在线干燥提供了实验基础。
文摘Quasi-elastic neutron scattering(QENS) has many applications that are directly related to the development of highperformance functional materials and biological macromolecules, especially those containing some water. The analysis method of QENS spectra data is important to obtain parameters that can explain the structure of materials and the dynamics of water. In this paper, we present a revised jump-diffusion and rotation-diffusion model(rJRM) used for QENS spectra data analysis. By the rJRM, the QENS spectra from a pure magnesium-silicate-hydrate(MSH) sample are fitted well for the Q range from 0.3 ^(-1) to 1.9 ^(-1) and temperatures from 210 K up to 280 K. The fitted parameters can be divided into two kinds. The first kind describes the structure of the MSH sample, including the ratio of immobile water(or bound water) C and the confining radius of mobile water a_0. The second kind describes the dynamics of confined water in pores contained in the MSH sample, including the translational diffusion coefficient Dt, the average translational residence timeτ0, the rotational diffusion coefficient D_r, and the mean squared displacement(MSD) u^2. The r JRM is a new practical method suitable to fit QENS spectra from porous materials, where hydrogen atoms appear in both solid and liquid phases.
