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Nitric Oxide Abundance in the Martian Thermosphere and Its Diurnal Variation 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (9)
作者:  Cui, J.;  Fu, M-H;  Ren, Z-P;  Gu, H.;  Guo, J-H;  Wu, X-S;  Wu, Z-P;  Lai, H-R;  Wei, Y.
收藏  |  浏览/下载:22/0  |  提交时间:2020/07/02
nitric oxide  Mars  diurnal variation  Mass spectrometer  thermosphere  
Detection of metastable electronic states by Penning trap mass spectrometry 期刊论文
NATURE, 2020, 581 (7806) : 42-+
作者:  Rauch, Jennifer N.;  Luna, Gabriel;  Guzman, Elmer;  Audouard, Morgane;  Challis, Collin;  Sibih, Youssef E.;  Leshuk, Carolina;  Hernandez, Israel;  Wegmann, Susanne;  Hyman, Bradley T.;  Gradinaru, Viviana;  Kampmann, Martin;  Kosik, Kenneth S.
收藏  |  浏览/下载:28/0  |  提交时间:2020/07/03

State-of-the-art optical clocks(1) achieve precisions of 10(-18) or better using ensembles of atoms in optical lattices(2,3) or individual ions in radio-frequency traps(4,5). Promising candidates for use in atomic clocks are highly charged ions(6) (HCIs) and nuclear transitions(7), which are largely insensitive to external perturbations and reach wavelengths beyond the optical range(8) that are accessible to frequency combs(9). However, insufficiently accurate atomic structure calculations hinder the identification of suitable transitions in HCIs. Here we report the observation of a long-lived metastable electronic state in an HCI by measuring the mass difference between the ground and excited states in rhenium, providing a non-destructive, direct determination of an electronic excitation energy. The result is in agreement with advanced calculations. We use the high-precision Penning trap mass spectrometer PENTATRAP to measure the cyclotron frequency ratio of the ground state to the metastable state of the ion with a precision of 10(-11)-an improvement by a factor of ten compared with previous measurements(10,11). With a lifetime of about 130 days, the potential soft-X-ray frequency reference at 4.96 x 10(16) hertz (corresponding to a transition energy of 202 electronvolts) has a linewidth of only 5 x 10(-8) hertz and one of the highest electronic quality factors (10(24)) measured experimentally so far. The low uncertainty of our method will enable searches for further soft-X-ray clock transitions(8,12) in HCIs, which are required for precision studies of fundamental physics(6).


Penning trap mass spectrometry is used to measure the electronic transition energy from a long-lived metastable state to the ground state in highly charged rhenium ions with a precision of 10(-11).


  
A Black Carbon-Tracer Method for Estimating Cooking Organic Aerosol From Aerosol Mass Spectrometer Measurements 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (14) : 8474-8483
作者:  He, Yao;  Sun, Yele;  Wang, Qingqing;  Zhou, Wei;  Xu, Weiqi;  Zhang, Yunjiang;  Xie, Conghui;  Zhao, Jian;  Du, Wei;  Qiu, Yanmei;  Le, Lu;  Fu, Pingqing;  Wang, Zifa;  Worsnop, Douglas R.
收藏  |  浏览/下载:22/0  |  提交时间:2019/11/27
Cooking organic aerosol  aerosol mass spectrometer  Black carbon  Primary organic aerosol  
Characterization of Aerosol Aging Potentials at Suburban Sites in Northern and Southern China Utilizing a Potential Aerosol Mass (Go:PAM) Reactor and an Aerosol Mass Spectrometer 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2019, 124 (10) : 5629-5649
作者:  Li, Jinjian;  Liu, Qianyun;  Li, Yongjie;  Liu, Tengyu;  Huang, Dandan;  Zheng, Jing;  Zhu, Wenfei;  Hu, Min;  Wu, Yusheng;  Lou, Shengrong;  Hallquist, Asa M.;  Hallquist, Mattias;  Chan, Chak K.;  Canonaco, Francesco;  Prevot, Andre S. H.;  Fung, Jimmy C. H.;  Lau, Alexis K. H.;  Yu, Jian Zhen
收藏  |  浏览/下载:27/0  |  提交时间:2019/11/26
potential aerosol mass  aerosol mass spectrometer  suburban Beijing  suburban Hong Kong  
Regional Similarities and NOx-Related Increases in Biogenic Secondary Organic Aerosol in Summertime Southeastern United States 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2018, 123 (18) : 10620-10636
作者:  Liu, Jun;  Russell, Lynn M.;  Ruggeri, Giulia;  Takahama, Satoshi;  Claflin, Megan S.;  Ziemann, Paul J.;  Pye, Havala O. T.;  Murphy, Benjamin N.;  Xu, Lu;  Ng, Nga L.;  McKinney, Karena A.;  Budisulistiorini, Sri Hapsari;  Bertram, Timothy H.;  Nenes, Athanasios;  Surratt, Jason D.
收藏  |  浏览/下载:24/0  |  提交时间:2019/04/09
biogenic organic aerosol  positive matrix factorization  aerosol mass spectrometer  Fourier transform infrared spectroscopy  NOx  
Organic Aerosol Particle Chemical Properties Associated With Residential Burning and Fog in Wintertime San Joaquin Valley (Fresno) and With Vehicle and Firework Emissions in Summertime South Coast Air Basin (Fontana) 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2018, 123 (18) : 10707-10731
作者:  Chen, Chia-Li;  Chen, Sijie;  Russell, Lynn M.;  Liu, Jun;  Price, Derek J.;  Betha, Raghu;  Sanchez, Kevin J.;  Lee, Alex K. Y.;  Williams, Leah;  Collier, Sonya C.;  Zhang, Qi;  Kumar, Anikender;  Kleeman, Michael J.;  Zhang, Xiaolu;  Cappa, Christopher D.
收藏  |  浏览/下载:40/0  |  提交时间:2019/04/09
organic aerosol  positive matrix factorization  aerosol mass spectrometer  amines  light-scattering single particle  
Final Report: "Collaborative Project. Understanding the Chemical Processes That Affect Growth Rates of Freshly Nucleated Particles" 科技报告
来源:US Department of Energy (DOE). 出版年: 2015
作者:  Smith, James N.;  McMurry, Peter H.
收藏  |  浏览/下载:14/0  |  提交时间:2019/04/05
atmospheric new particle formation  thermal desorption chemical ionization mass spectrometer  nanoparticle  nucleation  
Collaborative Project: Understanding the Chemical Processes tat Affect Growth rates of Freshly Nucleated Particles 科技报告
来源:US Department of Energy (DOE). 出版年: 2015
作者:  McMurry, Peter;  Smuth, James
收藏  |  浏览/下载:12/0  |  提交时间:2019/04/05
atmospheric new particle formation  thermal desorption chemical ionization mass spectrometer  nanoparticle  nucleation  
Aerosol Mass Spectrometry via Laser-Induced Incandescence Particle Vaporization Final Report 科技报告
来源:US Department of Energy (DOE). 出版年: 2011
作者:  Zhou, Nan;  Price, Lynn;  Zheng, Nina;  Ke, Jing;  Hasanbeigi, Ali
收藏  |  浏览/下载:22/0  |  提交时间:2019/04/05
soot particles  aerosol mass spectrometer