通过扩散法制得低浓度的对甲基膦酸二甲酯(DMMP)、磷酸三丁酯(TBP)、二甲基亚砜(DMSO)3种化学战剂模拟剂蒸气,并用自制紫外光离子源高场不对称波形离子迁移谱仪(Ultraviolet photoionization high field asymmetric ion mobility spectr...通过扩散法制得低浓度的对甲基膦酸二甲酯(DMMP)、磷酸三丁酯(TBP)、二甲基亚砜(DMSO)3种化学战剂模拟剂蒸气,并用自制紫外光离子源高场不对称波形离子迁移谱仪(Ultraviolet photoionization high field asymmetric ion mobility spectrometry,UV-FAIMS)对其进行检测,得到不同样品在不同分离电压下特征谱图,并通过对多组分离电压(Dispersion voltage,DV)和补偿电压(Compensation voltage,CV)求解,建立了α2和α4二维谱图,提高了FAIMS的分辨识别能力。此外,对UV-FAIMS的检测灵敏度进行了测定。实验表明,此系统对甲基膦酸二甲酯(DMMP)的检测灵敏度优于0.55μg/L。展开更多
氨是水体主要的污染物之一,其含量是水质评估的重要参数。本研究采用真空紫外光离子源-高场不对称波形离子迁移谱(Ultraviolet photoionization high field asymmetric waveform ion mobility spectrometry,UVFAIMS)技术,发展一种的水...氨是水体主要的污染物之一,其含量是水质评估的重要参数。本研究采用真空紫外光离子源-高场不对称波形离子迁移谱(Ultraviolet photoionization high field asymmetric waveform ion mobility spectrometry,UVFAIMS)技术,发展一种的水中氨含量的现场快速检测方法。通过对比标准氨样品和水中微量氨UV-FAIMS谱图峰的特征补偿电压(Compensation voltage,CV)值,确定了水中HN+4的特征离子峰位置;研究了不同分离电压(Dispersion voltages,DV)下HN_4^+谱图峰位置的关系,获得了HN_4^+的特征识别系数α_2和α_4分别为2.21×10^(-5)Td^(-2)和-1.45323×10^(-9)Td^(-4);通过不同浓度样品的信号响应,研究了UV-FAIMS对水中氨的检出限,在信噪比为3的情况下达到了9.2μg/L。本研究为水中氨现场检测提供了一种快速、无需前处理的技术手段。展开更多
Nd^3＋ ：NaLa（WO4）2 crystals with a dimension up to 7 mm were grown from a high temperature solution using a double-crucible method. Scanning electron microscopy observations of the crystals showed that there were n...Nd^3＋ ：NaLa（WO4）2 crystals with a dimension up to 7 mm were grown from a high temperature solution using a double-crucible method. Scanning electron microscopy observations of the crystals showed that there were no small cracks on the surface of the crystals although they underwent two phase transitions when cooling down from high temperatures. X-ray diffraction studies indicated that the as-obtained product is pure low- temperature tetragonal Nd^3＋ ：NaLa（WO4）2. The absorption and fluorescence spectra for Nd^3＋ ：NaLa（WO4）2 were measured at room temperature. The absorption band at 804 nm has a wide full-width half maximum of 23 nm whose origin is discussed. The absorption and emission cross sections were calculated to be 7.24×10^-20 cm^2 at 804 nm and 6.54×10 ^-20 cm^2 at 1057 nm, respectively.展开更多
文摘通过扩散法制得低浓度的对甲基膦酸二甲酯(DMMP)、磷酸三丁酯(TBP)、二甲基亚砜(DMSO)3种化学战剂模拟剂蒸气,并用自制紫外光离子源高场不对称波形离子迁移谱仪(Ultraviolet photoionization high field asymmetric ion mobility spectrometry,UV-FAIMS)对其进行检测,得到不同样品在不同分离电压下特征谱图,并通过对多组分离电压(Dispersion voltage,DV)和补偿电压(Compensation voltage,CV)求解,建立了α2和α4二维谱图,提高了FAIMS的分辨识别能力。此外,对UV-FAIMS的检测灵敏度进行了测定。实验表明,此系统对甲基膦酸二甲酯(DMMP)的检测灵敏度优于0.55μg/L。
文摘氨是水体主要的污染物之一,其含量是水质评估的重要参数。本研究采用真空紫外光离子源-高场不对称波形离子迁移谱(Ultraviolet photoionization high field asymmetric waveform ion mobility spectrometry,UVFAIMS)技术,发展一种的水中氨含量的现场快速检测方法。通过对比标准氨样品和水中微量氨UV-FAIMS谱图峰的特征补偿电压(Compensation voltage,CV)值,确定了水中HN+4的特征离子峰位置;研究了不同分离电压(Dispersion voltages,DV)下HN_4^+谱图峰位置的关系,获得了HN_4^+的特征识别系数α_2和α_4分别为2.21×10^(-5)Td^(-2)和-1.45323×10^(-9)Td^(-4);通过不同浓度样品的信号响应,研究了UV-FAIMS对水中氨的检出限,在信噪比为3的情况下达到了9.2μg/L。本研究为水中氨现场检测提供了一种快速、无需前处理的技术手段。
文摘Nd^3＋ ：NaLa（WO4）2 crystals with a dimension up to 7 mm were grown from a high temperature solution using a double-crucible method. Scanning electron microscopy observations of the crystals showed that there were no small cracks on the surface of the crystals although they underwent two phase transitions when cooling down from high temperatures. X-ray diffraction studies indicated that the as-obtained product is pure low- temperature tetragonal Nd^3＋ ：NaLa（WO4）2. The absorption and fluorescence spectra for Nd^3＋ ：NaLa（WO4）2 were measured at room temperature. The absorption band at 804 nm has a wide full-width half maximum of 23 nm whose origin is discussed. The absorption and emission cross sections were calculated to be 7.24×10^-20 cm^2 at 804 nm and 6.54×10 ^-20 cm^2 at 1057 nm, respectively.
