{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T02:17:50Z","timestamp":1769998670654,"version":"3.49.0"},"reference-count":13,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2010,5,4]],"date-time":"2010-05-04T00:00:00Z","timestamp":1272931200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Correct measurements of ammonia concentration in air still present considerable challenges. The high water solubility and polarity can cause it to adsorb on surfaces in the entire sampling system, including sampling lines, filters, valves, pumps and instruments, causing substantial measuring errors and time delays. To estimate time delay characteristics of a Photo Acoustic Multi Gas Monitor 1312 and a Multi Point Sampler continuous measurement of aerial ammonia concentrations at different levels was performed. In order to obtain reproducible data, a wind tunnel was used to generate selected concentrations inside and a background concentration representing the air inlet of the tunnel. Four different concentration levels (0.8 ppm, 6.2 ppm, 9.7 ppm and 13.7 ppm) were used in the experiments, with an additional outdoor concentration level as background. The results indicated a substantial time delay when switching between the measuring positions with high and low concentration and vice versa. These properties may course serious errors for estimation of e.g. gas emissions whenever more than one measuring channel is applied. To reduce the measurement errors, some suggestions regarding design of the measurement setup and measuring strategies were presented.<\/jats:p>","DOI":"10.3390\/s100504634","type":"journal-article","created":{"date-parts":[[2010,5,4]],"date-time":"2010-05-04T11:18:03Z","timestamp":1272971883000},"page":"4634-4642","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Time Delay for Aerial Ammonia Concentration Measurements in Livestock Buildings"],"prefix":"10.3390","volume":"10","author":[{"given":"Hans Benny","family":"Rom","sequence":"first","affiliation":[{"name":"Department of Biosystems Engineering, University of Aarhus, Faculty of Agricultural Sciences, Blichers Alle 20, DK-8830 Tjele, Denmark"}]},{"given":"Guo-Qiang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Biosystems Engineering, University of Aarhus, Faculty of Agricultural Sciences, Blichers Alle 20, DK-8830 Tjele, Denmark"}]}],"member":"1968","published-online":{"date-parts":[[2010,5,4]]},"reference":[{"key":"ref_1","first-page":"203","article-title":"Sampling and Measurement of Ammonia at Animal Facilities","volume":"98","author":"Ni","year":"2008","journal-title":"Adv. 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Res"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1016\/j.biosystemseng.2009.02.004","article-title":"Multi-Location Measurements of Greenhouse Gases and Emission Rates of Methane and Ammonia from a Naturally-Ventilated Barn for Dairy Cows","volume":"103","author":"Ngwabie","year":"2009","journal-title":"J. Biosyst. Eng"},{"key":"ref_5","unstructured":"Rom, H.B. Evaluation of Photoacoustic Ammonia Detection in livestock Buildings. Milan, Italy."},{"key":"ref_6","unstructured":"Rom, H.B. (1995). Ammonia Emission from Pig Confinement Buildings. System Analysis and Measuring Methods, Ph.D. Thesis."},{"key":"ref_7","first-page":"03","article-title":"Assessment of Ammonia Adsorption onto Teflon and LDPE Tubing used in Pollutant Stream Conveyance","volume":"5","author":"Mukhtar","year":"2003","journal-title":"Agri. Eng. Int.: CIGR J. Sci. Res. Develop"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"919","DOI":"10.13031\/2013.22253","article-title":"Ammonia Adsorption in five Types of Flexible Tubing Materials","volume":"22","author":"Shah","year":"2006","journal-title":"ASABE App. Eng. Agr"},{"key":"ref_9","unstructured":"Rose, A.J., Mukhtar, S., Lacey, R.E., Shaw, B.W., and Parnell, C.B. (2003). Assessment of Ammonia Adsorption to Polymer Tubings. ASAE Annual Meeting July, 034106."},{"key":"ref_10","unstructured":"Luma Sense Available online: www.lumasense.dk\/INNOVA-1412.gas_monitoring4.0.html\/ (accessed on 3 April 2010)."},{"key":"ref_11","unstructured":"Luma Sense Available online: www.lumasense.dk\/INNOVA-1303.gas_monitoring6.0.html\/ (accessed on 3 April 2010)."},{"key":"ref_12","unstructured":"Luma Sense Available online: www.lumasense.dk\/INNOVA-1309.gas_monitoring5.0.html\/ (accessed on 6 April 2010)."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1109","DOI":"10.13031\/2013.17256","article-title":"Continuous Measurement of Nitrous Oxide and Methane Emission in Pig Units by Infrared Photoacoustic Detection","volume":"41","author":"Osada","year":"1998","journal-title":"Trans. ASAE"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/5\/4634\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:02:20Z","timestamp":1760220140000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/5\/4634"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,5,4]]},"references-count":13,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2010,5]]}},"alternative-id":["s100504634"],"URL":"https:\/\/doi.org\/10.3390\/s100504634","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,5,4]]}}}