We calculated the harmonic spectra generated from the asymmetric molecules of HD^＋ and HeH^2＋. It is found that HD＋produces only odd harmonics, while HeH^2＋produces both odd and even harmonics. Further analysis re...We calculated the harmonic spectra generated from the asymmetric molecules of HD^＋ and HeH^2＋. It is found that HD＋produces only odd harmonics, while HeH^2＋produces both odd and even harmonics. Further analysis reveals that for both HD^＋ and HeH^2＋, the nuclear dipole acceleration can generate even harmonics, but it is three orders of magnitude lower than that of the electron. Hence, the electronic dipole acceleration dominates the harmonic generation. For HD^＋,the electronic dipole acceleration only contributes to the generation of odd harmonics, but for HeH^2＋it contributes to the generation of both odd and even harmonics. Besides, one concept of the broken degree of system-symmetry is proposed to explain the different odd-even property between the harmonic spectra of HD^＋ and HeH^2＋.展开更多
The spectral attenuation of a 400-nm probe laser propagating through a femtosecond plasma in air is studied.Defocusing effect of the low-density plasma is an obvious effect by examining the far-field patterns of the 4...The spectral attenuation of a 400-nm probe laser propagating through a femtosecond plasma in air is studied.Defocusing effect of the low-density plasma is an obvious effect by examining the far-field patterns of the 400-nm pulse.Besides,the energy of 400-nm pulse drops after interaction with the plasma,which is found to be another effect leading to the attenuation.To reveal the physical origin behind the energy loss,we measure fluorescence emissions of the interaction area.The fluorescence is hardly detected with the weak 400-nm laser pulse,and the line spectra from the plasma filament induced by the 800-nm pump pulse are clearly shown.However,when the 400-nm pulse propagates through the plasma filament,the fluorescence at 391 nm from the first negative band system of N2+is enhanced,while that from the second positive band of neutral N2 at 337 nm remains constant.Efficient near-resonant absorption of the 400-nm pulse by the first negative band system occurs inside the plasma,which results in the enhanced fluorescence.Furthermore,the spectral attenuation of the 400-nm probe laser is measured as a function of the pump–probe time delay as well as the pump-pulse energy.展开更多
目的采用环介导等温扩增(LAMP)技术建立针对人肺炎衣原体基因的特异、灵敏、快速、可视的检测方法。方法对Gen Bank登录的肺炎衣原体的Omp1基因序列进行生物学分析,利用Primer Explorer V4软件,针对保守区域设计LAMP引物,建立并优化反...目的采用环介导等温扩增(LAMP)技术建立针对人肺炎衣原体基因的特异、灵敏、快速、可视的检测方法。方法对Gen Bank登录的肺炎衣原体的Omp1基因序列进行生物学分析,利用Primer Explorer V4软件,针对保守区域设计LAMP引物,建立并优化反应条件,对其特异性、灵敏度和稳定性进行评估。结果该方法能特异性扩增出肺炎衣原体,而对流感病毒、副流感病毒、呼吸道合胞病毒、人腺病毒、人博卡病毒均无特异反应,其最低检测限度为50copies/μL。另外,反应周期可在50 min内完成,并通过反应液中加入荧光染料来对结果进行可视化判读。结论本研究建立的针对人肺炎衣原体的LAMP检测方法具有特异性强、灵敏度高、简便快速、可视化判读结果、成本低等优势,为基层或现场进行肺炎衣原体的快速确诊提供了可靠的技术支撑。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11404153,11135002,11475076,and 11405077)the Fundamental Research Funds for the Central Universities of China(Grants Nos.lzujbky-2016-29,lzujbky-2016-31,and lzujbky-2016-209)
文摘We calculated the harmonic spectra generated from the asymmetric molecules of HD^＋ and HeH^2＋. It is found that HD＋produces only odd harmonics, while HeH^2＋produces both odd and even harmonics. Further analysis reveals that for both HD^＋ and HeH^2＋, the nuclear dipole acceleration can generate even harmonics, but it is three orders of magnitude lower than that of the electron. Hence, the electronic dipole acceleration dominates the harmonic generation. For HD^＋,the electronic dipole acceleration only contributes to the generation of odd harmonics, but for HeH^2＋it contributes to the generation of both odd and even harmonics. Besides, one concept of the broken degree of system-symmetry is proposed to explain the different odd-even property between the harmonic spectra of HD^＋ and HeH^2＋.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1932133,51733004,51525303,and 21702085)the Fundamental Research Funds for the Central Universities,China(Grant Nos.lzujbky-2016-35 and lzujbky-2018-it36)
文摘The spectral attenuation of a 400-nm probe laser propagating through a femtosecond plasma in air is studied.Defocusing effect of the low-density plasma is an obvious effect by examining the far-field patterns of the 400-nm pulse.Besides,the energy of 400-nm pulse drops after interaction with the plasma,which is found to be another effect leading to the attenuation.To reveal the physical origin behind the energy loss,we measure fluorescence emissions of the interaction area.The fluorescence is hardly detected with the weak 400-nm laser pulse,and the line spectra from the plasma filament induced by the 800-nm pump pulse are clearly shown.However,when the 400-nm pulse propagates through the plasma filament,the fluorescence at 391 nm from the first negative band system of N2+is enhanced,while that from the second positive band of neutral N2 at 337 nm remains constant.Efficient near-resonant absorption of the 400-nm pulse by the first negative band system occurs inside the plasma,which results in the enhanced fluorescence.Furthermore,the spectral attenuation of the 400-nm probe laser is measured as a function of the pump–probe time delay as well as the pump-pulse energy.
文摘目的采用环介导等温扩增(LAMP)技术建立针对人肺炎衣原体基因的特异、灵敏、快速、可视的检测方法。方法对Gen Bank登录的肺炎衣原体的Omp1基因序列进行生物学分析,利用Primer Explorer V4软件,针对保守区域设计LAMP引物,建立并优化反应条件,对其特异性、灵敏度和稳定性进行评估。结果该方法能特异性扩增出肺炎衣原体,而对流感病毒、副流感病毒、呼吸道合胞病毒、人腺病毒、人博卡病毒均无特异反应,其最低检测限度为50copies/μL。另外,反应周期可在50 min内完成,并通过反应液中加入荧光染料来对结果进行可视化判读。结论本研究建立的针对人肺炎衣原体的LAMP检测方法具有特异性强、灵敏度高、简便快速、可视化判读结果、成本低等优势,为基层或现场进行肺炎衣原体的快速确诊提供了可靠的技术支撑。
