000136082 001__ 136082 000136082 005__ 20240712101031.0 000136082 0247_ $$2ISSN$$a0366-0885 000136082 0247_ $$2Handle$$a2128/3397 000136082 037__ $$aPreJuSER-136082 000136082 041__ $$aEnglish 000136082 082__ $$a500 000136082 0881_ $$aJuel-2650 000136082 088__ $$2JUEL$$aJuel-2650 000136082 1001_ $$aEhhalt, D. H.$$b0$$ufzj 000136082 245__ $$aDistribution of C1 - C2 Aldehydes in the Free Troposphere 000136082 260__ $$aJülich$$bForschungszentrum Jülich GmbH Zentralbibliothek, Verlag$$c1992 000136082 300__ $$a127 S. 000136082 3367_ $$0PUB:(DE-HGF)29$$2PUB:(DE-HGF)$$aReport$$mreport 000136082 3367_ $$2DataCite$$aOutput Types/Report 000136082 3367_ $$2BibTeX$$aTECHREPORT 000136082 3367_ $$2ORCID$$aREPORT 000136082 3367_ $$010$$2EndNote$$aReport 000136082 3367_ $$2DRIVER$$areport 000136082 4900_ $$0PERI:(DE-600)2414853-2$$aBerichte des Forschungszentrum Jülich 000136082 500__ $$aRecord converted from JUWEL: 18.07.2013 000136082 520__ $$aA sensitive and selective measurement technique for the determination of tropospheric formaldehyde and acetaldehyde in background air is described . The method is based on the derivatization of aldehydes with 2,4 dinitrophenylhydrazine (DNPH) . The derivative aldehyde hydrazones are then separated using high performance liquid chromatography (HPLC) and detected at 355 nm using a conventional HPLC UV/VIS absorbance detector. Aldehydes were collected with Waters Sep-Pak C®18 DNPHcoated cartridges using a portable sampling system . The apparatus proved to be easy and convenient to operate, even in remote clean air locations where aldehyde mixing ratios and their natural variations are likely to be of special interest in air chemistry. The method was used for ground-based measurements of formaldehyde and acetaldehyde during an uninterupted two-week period in August 1990 in Jülich . Ground level measurements in Jülich for formaldehyde and acetaldehyde were shown to vary from 0 .5 to 7 ppb and 0 .1 to 2 .0 ppb, respectively . Diurnal mean mixing ratios of, formaldehyde and acetaldehyde were 2 .8 +/® 1 .5 ppb and 0 .7 -+/® 0 .4 ppb respectively . Significant diurnal patterns were observed with maximum mixing ratios in the early afternoons, and minimum mixing ratios shortly before sunrise . A potential interference from organic hydroperoxides is also discussed. ~n~'r cr ai6~ 9 ~ Lv~ vr.m. $ re measurements up ac .o nearly ~ 8L811 är J=s t he s.~ai ;f ei a•®rs-I an, in z vi av,=-rns, -F ver‘fw { .°174YiF.9'i ®~fl to November 1 9 4 0 showed the potential of cartridge-based methods for aldehyde measurements in the free troposphere . These test flights indicated that formaldehyde vertical profiles can be dependent on inversion height and cloud frequency . In-cloud formaldehyde measurements tended to be lower than gas-phase measurements 000136082 7001_ $$aSchmidt, U.$$b1$$ufzj 000136082 7001_ $$aArlander, D. W.$$b2$$ufzj 000136082 8564_ $$uhttps://juser.fz-juelich.de/record/136082/files/J%C2%A9%C6%A1l_2650_Arlander.pdf$$yOpenAccess 000136082 909CO $$ooai:juser.fz-juelich.de:136082$$pdnbdelivery$$pVDB$$pdriver$$popen_access$$popenaire 000136082 915__ $$0StatID:(DE-HGF)0510$$2StatID$$aOpenAccess 000136082 9201_ $$0I:(DE-Juel1)VDB791$$kICG-2$$lTroposphäre$$x0 000136082 970__ $$a2128/3397 000136082 9801_ $$aFullTexts 000136082 980__ $$aI:(DE-Juel1)IEK-8-20101013 000136082 980__ $$aUNRESTRICTED 000136082 980__ $$aJUWEL 000136082 980__ $$aConvertedRecord 000136082 980__ $$areport 000136082 980__ $$aFullTexts 000136082 980__ $$aVDB 000136082 981__ $$aI:(DE-Juel1)ICE-3-20101013 000136082 981__ $$aI:(DE-Juel1)IEK-8-20101013