000136081 001__ 136081
000136081 005__ 20240712101014.0
000136081 0247_ $$2ISSN$$a0366-0885
000136081 0247_ $$2Handle$$a2128/3396
000136081 037__ $$aPreJuSER-136081
000136081 041__ $$aEnglish
000136081 082__ $$a540
000136081 0881_ $$aJuel-1756
000136081 088__ $$2JUEL$$aJuel-1756
000136081 1001_ $$aEhhalt, D. H .$$b0$$ufzj
000136081 245__ $$aThe Tropospheric Distribution of Formaldehyde
000136081 260__ $$aJülich$$bKernforschungsanlage Jülich GmbH, Zentralbibliothek, Verlag$$c1981
000136081 300__ $$a100 S.
000136081 3367_ $$0PUB:(DE-HGF)29$$2PUB:(DE-HGF)$$aReport$$mreport
000136081 3367_ $$2DataCite$$aOutput Types/Report
000136081 3367_ $$2BibTeX$$aTECHREPORT
000136081 3367_ $$2ORCID$$aREPORT
000136081 3367_ $$010$$2EndNote$$aReport
000136081 3367_ $$2DRIVER$$areport
000136081 4900_ $$0PERI:(DE-600)2414853-2$$aBerichte der Kernforschungsanlage Jülich$$v1756
000136081 500__ $$aRecord converted from JUWEL: 18.07.2013
000136081 520__ $$aA new measurement technique for determining the very low formaldehyde (HCHO) concentrations in clean air is described. The method is based on the standard derivatisation of formaldehyde with 2,4-dinitrophenylhydrazine. The derivative, formaldehyde 2,4-dinitrophenylhydrazone, is seperated using high performance liquid chromatography and detected at 254 nm with a conventional UV absorbance detector. Formaldehyde was sampled using a specially developed battery powered portable apparatus. This equipment proved to be easy and convenient to operate, even in remote clean air locations where the formaldehyde mixing ratio and its natural variations are likely to be of especial interest in air chemistry. The sampling and analysis technique have been used to measure tropospheric mixing ratios at various places in Europe and New Zealand as well as during a ship cruise in the North and South Atlantic. In addition vertical profiles of the formaldehyde mixing ratio were obtained during several aircraft flights up to 7 km above the Eifel district of the Federal Republic of Germany. The results of the measurements show that formaldehyde mixing ratios in clean air are very low. At ground level, values are about 0.2 ppbv and decrease with altitude, with values under 0.1 ppbv at 7 km being observed. In clean maritime air no significant difference in the formaldehyde mixing ratio between the hemispheres was observed. In the mid Atlantic, diurnal variations of the formaldehyde mixing ratio showing weak maxima during the early afternoon were occasionally observed. These variations were attributed to the diurnal behaviour of the photochemical production and destruction of formaldehyde during stable weather conditions. Measurements in polluted air at Jülich in the Federal Republic of Germany and in the continental boundary layer showed high variable mixing ratios which were undoubtedly due to industrial and vehicular sources of formaldehyde.
000136081 7001_ $$aSchmidt, U.$$b1$$ufzj
000136081 7001_ $$aLowe, D. C.$$b2$$eCorresponding author$$ufzj
000136081 8564_ $$uhttps://juser.fz-juelich.de/record/136081/files/J%C2%A9%C6%A1l_1756_Lowe.pdf$$yOpenAccess
000136081 909CO $$ooai:juser.fz-juelich.de:136081$$pdnbdelivery$$pVDB$$pdriver$$popen_access$$popenaire
000136081 915__ $$0StatID:(DE-HGF)0510$$2StatID$$aOpenAccess
000136081 9201_ $$0I:(DE-Juel1)VDB791$$kICG-2$$lTroposphäre$$x0
000136081 970__ $$a2128/3396
000136081 9801_ $$aFullTexts
000136081 980__ $$aI:(DE-Juel1)IEK-8-20101013
000136081 980__ $$aUNRESTRICTED
000136081 980__ $$aJUWEL
000136081 980__ $$aConvertedRecord
000136081 980__ $$areport
000136081 980__ $$aFullTexts
000136081 980__ $$aVDB
000136081 981__ $$aI:(DE-Juel1)ICE-3-20101013
000136081 981__ $$aI:(DE-Juel1)IEK-8-20101013