1.
|
|
2.
|
Performance of diethylene glycol-based particle counters in the sub-3 nm size range
/ Wimmer, D (Goethe U., Frankfurt (main)) ; Lehtipalo, K (Helsinki U. ; Airmodus, Helsinki) ; Franchin, A (Helsinki U.) ; Kangasluoma, J (Helsinki U.) ; Kreissl, F (Goethe U., Frankfurt (main)) ; Kürten, A (Goethe U., Frankfurt (main)) ; Kupc, A (U. Vienna (main)) ; Metzger, A (Goethe U., Frankfurt (main)) ; Mikkilä, J (Airmodus, Helsinki) ; Petäjä, J (Helsinki U.) et al.
When studying new particle formation, the uncertainty in determining the "true" nucleation rate is considerably reduced when using condensation particle counters (CPCs) capable of measuring concentrations of aerosol particles at sizes close to or even at the critical cluster size (1–2 nm). Recently, CPCs able to reliably detect particles below 2 nm in size and even close to 1 nm became available. [...]
2013
- Published in : Atmos. Meas. Tech. 6 (2013) 1793-1804
|
|
3.
|
A new high-transmission inlet for the Caltech nano-RDMA for size distribution measurements of sub-3 nm ions at ambient concentrations
/ Franchin, Alessandro (Helsinki U.) ; Downard, Andy (Caltech, Pasadena (main)) ; Kangasluoma, Juha (Helsinki U.) ; Nieminen, Tuomo (Helsinki U. ; Helsinki Inst. of Phys. ; UEF, Kuopio) ; Lehtipalo, Katrianne (Helsinki U. ; Airmodus Ltd, Helsinki) ; Steiner, Gerhard (U. Vienna (main) ; Innsbruck U.) ; Manninen, Hanna E (Helsinki U.) ; Petäjä, Tuukka (Helsinki U.) ; Flagan, Richard C (Caltech, Pasadena (main)) ; Kulmala, Markku (Helsinki U.)
Reliable and reproducible measurements of atmospheric aerosol particle number size distributions below 10 nm require optimized classification instruments with high particle transmission efficiency. Almost all differential mobility analyzers (DMAs) have an unfavorable potential gradient at the outlet (e.g., long column, Vienna type) or at the inlet (nano-radial DMA), preventing them from achieving a good transmission efficiency for the smallest nanoparticles. [...]
2016 - 12 p.
- Published in : Atmos. Meas. Tech. 9 (2016) 2709-2720
Fulltext: PDF; External link: Fulltext
|
|
4.
|
Technical Note: Using DEG-CPCs at upper tropospheric temperatures
/ Wimmer, D (Goethe U., Frankfurt (main) ; Helsinki U.) ; Lehtipalo, K (Helsinki U. ; Airmodus Ltd, Helsinki) ; Nieminen, T (Helsinki U.) ; Duplissy, J (Helsinki U.) ; Ehrhart, S (Goethe U., Frankfurt (main) ; CERN) ; Almeida, J (Goethe U., Frankfurt (main) ; CERN) ; Rondo, L (Goethe U., Frankfurt (main)) ; Franchin, A (Helsinki U.) ; Kreissl, F (Goethe U., Frankfurt (main)) ; Bianchi, F (PSI, Villigen ; Zurich, ETH) et al.
Over the last few years, several condensation particle counters (CPCs) capable of measuring in the sub-3 nm size range have been developed. Here we study the performance of CPCs based on diethylene glycol (DEG) at different temperatures during Cosmics Leaving OUtdoor Droplets (CLOUD) measurements at CERN. [...]
2015 - 9 p.
- Published in : Atmos. Chem. Phys. 15 (2015) 7547-7555
Fulltext: PDF;
|
|
5.
|
Methods for determining particle size distribution and growth rates between 1 and 3 nm using the Particle Size Magnifier
/ Lehtipalo, Katrianne (Helsinki U. ; Airmodus, Helsinki) ; Leppä, Johannes (Finnish Meteorological Inst.) ; Kontkanen, Jenni (Helsinki U.) ; Kangasluoma, Juha (Helsinki U.) ; Franchin, Alessandro (Helsinki U.) ; Wimmer, Daniela (Helsinki U.) ; Schobesberger, Siegfried (Helsinki U.) ; Junninen, Heikki (Helsinki U.) ; Petäjä, Tuukka (Helsinki U.) ; Sipilä, Mikko (Helsinki U.) et al.
The most important parameters describing the atmospheric new particle formation process are the particle formation and growth rates. These together determine the amount of cloud condensation nuclei attributed to secondary particle formation. [...]
2014
- Published in : Boreal Env. Res.: 19 (suppl. B) (2014) , pp. 215-236
|
|
6.
|
Modeling the thermodynamics and kinetics of sulfuric acid-dimethylamine-water nanoparticle growth in the CLOUD chamber
/ Ahlm, L (ACES, Stockholm University) ; Yli-Juuti, T (UEF, Kuopio) ; Schobesberger, S (Helsinki U. ; Washington U., Seattle) ; Praplan, A P (Helsinki U.) ; Kim, J (UEF, Kuopio) ; Tikkanen, O -P (UEF, Kuopio ; Helsinki U.) ; Lawler, M J (UC, Irvine) ; Smith, J N (UEF, Kuopio ; UC, Irvine) ; Tröstl, J (PSI, Villigen) ; Acosta Navarro, J C (ACES, Stockholm University) et al.
Dimethylamine (DMA) has a stabilizing effect on sulfuric acid (SA) clusters, and the SA and DMA molecules and clusters likely play important roles in both aerosol particle formation and growth in the atmosphere. We use the monodisperse particle growth model for acid-base chemistry in nanoparticle growth (MABNAG) together with direct and indirect observations from the CLOUD4 and CLOUD7 experiments in the cosmics leaving outdoor droplets (CLOUD) chamber at CERN to investigate the size and composition evolution of freshly formed particles consisting of SA, DMA, and water as they grow to 20 nm in dry diameter [...]
2016 - 16 p.
- Published in : Aerosol Sci. Technol. 50 (2016) 1017-1032
|
|
7.
|
|
8.
|
Hygroscopicity of nanoparticles produced from homogeneous nucleation in the CLOUD experiments
/ Kim, J (UEF, Kuopio) ; Ahlm, L (Stockholm U.) ; Yli-Juuti, T (UEF, Kuopio) ; Lawler, M (UEF, Kuopio ; NCAR, Boulder) ; Keskinen, H (UEF, Kuopio) ; Tröstl, J (PSI, Villigen) ; Schobesberger, S (Helsinki U.) ; Duplissy, J (Helsinki U.) ; Amorim, A (Lisbon, CENTRA) ; Bianchi, F (PSI, Villigen ; Zurich, ETH) et al.
Sulfuric acid, amines and oxidized organics have been found to be important compounds in the nucleation and initial growth of atmospheric particles. Because of the challenges involved in determining the chemical composition of objects with very small mass, however, the properties of the freshly nucleated particles and the detailed pathways of their formation processes are still not clear. [...]
2016 - 12 p.
- Published in : Atmosph. Chem. Phys. 16 (2016) 293-304
Fulltext: PDF;
|
|
9.
|
Neutral molecular cluster formation of sulfuric acid–dimethylamine observed in real time under atmospheric conditions
/ Kürten, Andreas (Goethe U., Frankfurt (main)) ; Jokinen, Tuija (Helsinki U.) ; Simon, Mario (Goethe U., Frankfurt (main)) ; Sipilä, Mikko (Helsinki U. ; Helsinki Inst. of Phys.) ; Sarnela, Nina (Helsinki U.) ; Junninen, Heikki (Helsinki U.) ; Adamov, Alexey (Helsinki U.) ; Almeida, João (Goethe U., Frankfurt (main) ; CERN) ; Amorim, Antonio (UBI, Covilha ; U. Lisbon (main)) ; Bianchi, Federico (PSI, Villigen) et al.
For atmospheric sulfuric acid (SA) concentrations the presence of dimethylamine (DMA) at mixing ratios of several parts per trillion by volume can explain observed boundary layer new particle formation rates. However, the concentration and molecular composition of the neutral (uncharged) clusters have not been reported so far due to the lack of suitable instrumentation. [...]
arXiv:1509.03474.-
2014
- Published in : Proc. Natl. Acad. Sci. U.S.A. 111 (2014) 15019-15024
External link: Fulltext
|
|
10.
|
A Novel Algorithm to Reconstruct Events in a Water Cherenkov Detector
/ Jia, Mo (SUNY, Stony Brook) ; Kumar, Karan (SUNY, Stony Brook) ; Mackey, Liam S (Rensselaer Polytech. Inst.) ; Putra, Alexander (City Coll., N.Y.) ; Vilela, Cristovao (CERN ; SUNY, Stony Brook) ; Wilking, Michael J (SUNY, Stony Brook) ; Xia, Junjie (Tokyo U., ICRR) ; Yanagisawa, Chiaki (SUNY, Stony Brook ; City Coll., N.Y.) ; Yang, Karan (Columbia U.)
We have developed a novel approach to reconstruct events detected by a water-based Cherenkov detector such as Super- and Hyper-Kamiokande using an innovative deep learning algorithm. The algorithm is based on a generative neural network whose parameters are obtained by minimizing a loss function. [...]
2022 - 4 p.
- Published in : PoS ICHEP2022 (2022) 976
Fulltext: PDF;
In : 41st International Conference on High Energy Physics (ICHEP 2022), Bologna, Italy, 6 - 13 Jul 2022, pp.976
|
|