Zobrazeno 1 - 10
of 22
pro vyhledávání: '"Juho Karhu"'
Publikováno v:
Photoacoustics, Vol 29, Iss , Pp 100443- (2023)
A photoacoustic detection of tritiated water (HTO) is presented. The method uses cantilever-enhanced photoacoustic spectroscopy (CEPAS) to reach sub-ppb sensitivity for HTO in the gas phase. A noise equivalent concentration of 0.88 ppb is reached wit
Externí odkaz:
https://doaj.org/article/ad3cfd92f3b24a2a8c67e3892cb34eeb
Publikováno v:
APL Photonics, Vol 6, Iss 2, Pp 026103-026103-10 (2021)
We present a simple method for fully stabilized mid-infrared optical frequency comb generation based on single-pass femtosecond optical parametric generation that is seeded by a continuous-wave laser. We have implemented the method in a periodically
Externí odkaz:
https://doaj.org/article/023afb79585b48d685d5af9433b09a86
Autor:
Juho Karhu, Tuomas Hieta
A real time trace gas detector for benzene is demonstrated. The measurement system takes an advantage of modest enrichment through short adsorption periods to reach a ppt-level detection limit with a sampling cycle of 90 s, which includes sample adso
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::dc48cf930255e9b6ad27a83bd7500cd9
http://hdl.handle.net/10138/355356
http://hdl.handle.net/10138/355356
Publikováno v:
University of Helsinki
We present here the first application of cantilever-enhanced photoacoustic spectroscopy for aerosol absorption measurements. A noise equivalent absorption of 1.3x10-10 cm-1 (one standard deviation) is reached with 20 s sampling time.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ad9aadca64355a1b5f305c70a6d57504
https://doi.org/10.1364/lacsea.2022.lw4d.5
https://doi.org/10.1364/lacsea.2022.lw4d.5
Autor:
Juho Karhu, Tuomas Hieta
A real time trace gas detector for benzene is demonstrated. The measurement system takes an advantage of modest enrichment through short adsorption periods to reach a ppt-level detection limit with a sampling cycle of 90 s, which includes sample adso
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e6d7f5f5759f25ea412fbfad1e18bbee
https://doi.org/10.33774/chemrxiv-2021-81d73
https://doi.org/10.33774/chemrxiv-2021-81d73
Publikováno v:
Karhu, J, Hieta, T, Manoocheri, F, Vainio, M & Ikonen, E 2021, ' LED-Based Photoacoustic NO 2 Sensor with a Sub-ppb Detection Limit ', ACS Sensors, vol. 6, no. 9, pp. 3303–3307 . https://doi.org/10.1021/acssensors.1c01073
Funding Information: The work was supported by the Academy of Finland (Project Numbers 326444 and 314364) and by the Academy of Finland’s Flagship Programme, Photonics Research and Innovation (PREIN), Decision Number: 320167. Publisher Copyright:
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::013e192695b951341bc499dbb84dc6b1
https://aaltodoc.aalto.fi/handle/123456789/110313
https://aaltodoc.aalto.fi/handle/123456789/110313
Publikováno v:
ACS sensors. 6(9)
A high-sensitivity light-emitting diode (LED)-based photoacoustic NO
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::f4efb38c3f10d1e1960e44e7a2ccba28
https://pubmed.ncbi.nlm.nih.gov/34506110
https://pubmed.ncbi.nlm.nih.gov/34506110
Publikováno v:
Optics letters. 46(16)
We demonstrate efficient generation of mid-infrared frequency combs based on continuous-wave-seeded femtosecond optical parametric generation in nonlinear waveguides. Conversion of the near-infrared pump to signal and idler light takes place with ver
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e8070a6ed1b5451c4a0edd6644bad0c1
https://pubmed.ncbi.nlm.nih.gov/34388805
https://pubmed.ncbi.nlm.nih.gov/34388805
Publikováno v:
2021 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC).
Optical Parametric Generation (OPG) has established itself as an alternative approach to difference frequency generation and optical parametrical oscillation for converting femtosecond pulses to the mid-infrared (MIR) spectral region [1] . Although i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d0f735fe1fa71b3ab1d0b767ffbbeacd
https://doi.org/10.1109/cleo/europe-eqec52157.2021.9541766
https://doi.org/10.1109/cleo/europe-eqec52157.2021.9541766
We demonstrate an approach for mid-infrared frequency comb generation based on femtosecond Optical Parametric Generation seeded by a continuous-wave laser. The offset frequency can be stabilized, continuously tuned and modulated without its direct de
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f315d5fb30923268ea9b2875df38956f
http://hdl.handle.net/10138/339057
http://hdl.handle.net/10138/339057