Levsen, K., Terlouw, J.K., Jobst, K.J., Elend, M., Preiß, A., ...
The collision-induced dissociations of the even-electron [M + H](+) and/or [M - H](-) ions of 121 model compounds (mainly small aromatic compounds with one to three functional groups) ionized by...
POHLMANN, G., PREISS, A., LEVSEN, K., RAABE, M., KOCH, W.
Objectives: The objective of the study described in this and an accompanying series of papers was to develop a laboratory generated exposure atmosphere to be used for chronic inhalation toxicity...
Pohlmann, G., Preiß, A., Levsen, K., Raabe, M., Koch, W.
OBJECTIVES: The objective of the study described in this and an accompanying series of papers was to develop a laboratory generated exposure atmosphere to be used for chronic inhalation toxicity...
Pohlmann, G., Preiss, A., Levsen, K., Raabe, M., Koch, W.
Objectives: The objective of the study described in this and an accompanying series of papers was to develop a laboratory generated exposure atmosphere to be used for chronic inhalation toxicity...
Pohlmann, G., Preiss, A., Levsen, K., Raabe, M., Koch, W.
Objectives: The objective of the study described in this and an accompanying series of papers was to develop a laboratory generated exposure atmosphere to be used for chronic inhalation toxicity...
Leng, G., Berger-Preiß, E., Levsen, K., Ranft, U., Sugiri, D., Hadnagy, W., ...
House dust and airborne particles (PM) were sampled before (T1) and 1 day (T2), 4-6 months (T3) as well as 10-12 months (T4) after a pest control operation (PCO). Cyfluthrin was applied in 11,...
Borlak, J., Blickwede, M., Hansen, T., Koch, W., Walles, M., Levsen, K.
Administration of therapeutic entities by inhalation opens new possibilities for drug entry into systemic circulation, but this requires passage through the alveolar epithelium. Little is known about...
Structure elucidation of phase II metabolites by tandem mass spectrometry: An overview (2005)
Levsen, K., Behnke, B., Dötzer, R., Dreher, W., Elend, M., ...
The present paper provides a summary of the collision-induced dissociation of protonated and deprotonated phase II metabolites of drugs and pesticides. This overview is based on published literature...
Mullet, W.M., Walles, M., Levsen, K., Borlak, J., Pawliszyn, J.
A new molecularly imprinted polymer (MIP) material was synthesized selective for verapamil and utilized for on-line metabolic screening of this common calcium antagonist in biological samples. Since...
Levsen, K., Preiß, A., Spraul, M.
HPLC coupled simultaneously to NMR and MS is particularly suited to the identification of unknown polar, non-volatile compounds in complex environmental samples, i.e. to non-target analysis of such...
Sandvoss, M., Preiß, A., Levsen, K., Weisemann, R., Spraul, M.
We report two new asterosaponins from the Baltic starfish Asterias rubens along with their 1H and 13C NMR data. The compounds were isolated after on-flow liquid chromatography-NMR-mass spectrometry...
Elflein, L., Berger-Preiss, E., Preiss, A., Elend, M., Levsen, K., Wünsch, G.
This work describes a gas chromatographic-mass spectrometric method employing negative chemical ionization (NCI) for the determination of E-cis/trans-chrysanthemumdicarboxylic acid (CDCA) in human...
Verapamil: Metabolism in cultures of primary human coronary arterial endothelial cells (2003)
Borlak, J., Walles, M., Levsen, K., Thum, T.
Endothelium is a metabolically active secretory tissue and an important barrier for metabolic products. Little is known about its contribution to drug oxidation. We investigated the gene and protein...
Borlak, J., Walles, M., Elend, M., Thum, T., Preiss, A., Levsen, K.
1. Verapamil is a well-known and world-wide prescribed calcium antagonist, but it suffers from extensive first-pass metabolism. Although it has been marketed for many years, a complete understanding...
Elflein, L., Berger-Preiß, E., Levsen, K., Wünsch, G.
This work presents a GC-MC method for the determination of 17 household insecticides and acaricides in indoor air. Air samples were collected with a sampling train which consisted of a glass fibre...
Walles, M., Thum, T., Levsen, K., Borlak, J.
Verapamil is a widely prescribed calcium antagonist, but suffers from extensive first pass metabolism. Despite its frequent use in drug metabolism a complete understanding of its metabolic pathway is...
Benfenati, E., Barcelo, D., Johnson, I., Galassi, S., Levsen, K.
This paper reports the main results obtained within the European Commission (EC)-funded project PERICLES. The main objective was the development and the evaluation of a protocol for an integrated...
Walles, M., Borlak, J., Levsen, K.
The potential of three genetic changes introduced into mice by the transgenic or knockout technology aimed at immortalizing hepatocytes in vitro and concomitantly preserving their differentiated...
Indoor pyrethroid exposure in homes with woollen textile floor coverings (2002)
Berger-Preiß, E., Levsen, K., Leng, G., Idel, H., Sugiri, D., Ranft, U.
In order to investigate human's exposure to permethrin from treated woollen textile floor coverings and possible adverse health effects, a study was carried out in 80 private homes in Hannover...
Development of a GC-MS method for the determination of household insecticides in indoor air (2002)
Elflein, L., Berger-Preiß, E., Levsen, K., Wünsch, G.
This work presents a GC-MS method for the determination of 17 household insecticides and acaricides in indoor air. Air samples were collected with a sampling train which consisted of a glass fibre...
Verapamil drug metabolism studies by automated in-tube solid phase microextraction (2002)
Walles, M., Mullett, W.M., Levsen, K., Borlak, J., Wünsch, G., Pawliszyn, J.
Verapamil is a common calcium antagonist described with antianginal, antihypertensive and antiarrythmic properties. The metabolites of verapamil have also shown pharmacological properties and...
Verapamil. New insight into the molecular mechanism of drug oxidation in the human heart (2002)
Walles, M., Thum, T., Levsen, K., Borlak, J.
Verapamil is a commonly prescribed cardiovascular drug, but surprisingly its metabolism in the target tissue of pharmacotherapy is basically unknown. We therefore investigated its biotransformation...
Berger-Preiß, E., Levsen, K., Ranft, U.
A study was carried out in order to investigate the indoor exposure to permethrin, in rooms containing wool textile floor coverings. In 80 private homes with wool rugs and wool wall-to-wall carpets,...
Mullett, W.M., Levsen, K., Lubda, D., Pawliszyn, J.
A restricted access material (RAM), alkyl-diol-silica (ADS), was used to prepare a highly bio-compatible solid-phase microextraction (SPME) capillary for the automated and direct in-tube extraction...
Mullett, W.M., Levsen, K., Borlak, J., Wu, J.C., Pawliszyn, J.
An automated in-tube solid-phase microextraction (SPME) HPLC analysis method for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and several metabolites has been developed. NNK is one of the...
Fuhst, R., Levsen, K., Koch, W., Muhle, H., Pohlmann, G., Preiß, A., ...
Pohlmann, G., Koch, W., Levsen, K., Preiß, A., Fuhst, R., Muhle, H., ...
Aromatic hydrocarbons in the atmospheric environment. Part III: Personal monitoring (2001)
Ilgen, E., Levsen, K., Angerer, J., Schneider, P., Heinrich, J., Wichmann, H.E.
As part of a larger study, personal sampling of the aromatic hydrocarbons benzene, toluene, ethylbenzene and the isomeric xylenes (BTEX) was carried out by 55 nonsmoking volunteers for a period of 14...
Ilgen, E., Levsen, K., Angerer, J., Schneider, P., Heinrich, J., Wichmann, H.E.
The concentrations of the aromatic hydrocarbons benzene, toluene, ethylbenzene and the isomeric xylenes (BTEX) have been determined in the indoor air of 115 private non-smoker homes (~380 individual...
Ilgen, E., Karfich, N., Levsen, K., Angerer, J., Schneider, P., Heinrich, J., ...
Six aromatic hydrocarbons (benzene, toluene, ethylbenzene and the three isomeric xylenes) were monitored in the indoor and outdoor air of 115 private non-smoker homes (~380 rooms), about half of...
Walles, M., Thum, T., Levsen, K., Borlak, J.
A substantial number of drugs act either directly or indirectly on the heart, but surprisingly, little is known about drug oxidation in the heart. We therefore investigated the metabolism of the...
Sandvoss, M., Weltring, A., Preiss, A., Levsen, K., Wuensch, G.
A combination of matrix solid-phase dispersion extraction (MSPD) and LC-NMR-MS hyphenation is proposed as a rapid screening method of natural products for unknown compounds. In this report, this new...
Belau, E., Grote, C., Spiekermann, M., Levsen, K.
An automated analyzer based on solid-phase microextraction (SPME) coupled to gas chromatography (GC) for monitoring organic compounds in water is presented. The instrumental setup, which was tested...
Die Belastung des Menschen durch Permethrin aus Wollteppichen und Wollteppichböden (2000)
Berger-Preiß, E., Kühn, K., Leng, G., Idel, H., Ranft, U., Levsen, K.
Sandvoss, M., Pham, L.H., Levsen, K., Preiß, A., Mügge, C., Wünsch, G.
LC-NMR-MS hyphenation has been applied in the screening of an asterosaponin subfraction obtained from the starfish Asterias rubens for unknown compounds. The suitability of this technique for...
Levsen, K., Preiß, A., Godejohann, M.
HPLC-1H NMR in combination with HPLC-MS is particularly suited to the identification of unknown polar, non-volatile compounds in complex environmental samples, i.e. to non-target analysis of such...
Preiß, A., Sänger, U., Karfich, N., Levsen, K., Mügge, C.
LC/NMR an LC/MS (the latter technique in the MSn mode) were used to characterize the organic constituents of industrial wastewater with emphasis on polar, nonvolatile compounds. In the effluent of a...
Quantitation of nonylphenols in an industrial textile effluent using GC-MS and LC-NMR (1999)
Benfenati, E., Pierucci, P., Fanelli, P., Preiss, A., Levsen, K.
Development of an SPME-GC method for the determination of organic compounds in waste water (1999)
Grote, C., Belau, E., Levsen, K., Wünsch, G.
A manual SPME method is presented for the analysis of organic compounds in industrial wastewater. 24 compounds commonly found in the wastewater of a chemical plant in northern Germany have been...
Human exposure to benzene and other hydrocarbons: indoor and outdoor sources (1999)
Levsen, K., Ilgen, E., Angerer, J., Schneider, P., Heinrich, J.
Biomonitoring of benzene and toluene in human blood by headspace-solid-phase microextraction (1999)
Schimming, E., Levsen, K., Köhme, C., Schürmann, W.
A simple and rapid method for the determination of benzene and toluene in whole blood by headspace-solid-phase microextraction (HS-SPME) is described. Using SPME fibres coated with 65 ug...
Grote, C., Levsen, K., Wünsch, G.
An automated system for quasi-continuous and on-site monitoring of organic compounds in water is presented. It is based on solid-phase microextraction (SPME) coupled to gas chromatography (GC) using...
Exposure to permethrin used as moth repellent in wool carpets (1999)
A study was carried out in order to investigate the indoor exposure to permethrin in rooms containing a wool carpet. In 80 private homes the concentrations of permethrin was monitored on airborne...
Benfenati, E., Piericci, P., Fanelli, R., Preiss, A., Godejohann, M., Astratov, M., ...
Nowadays, the need to have a realistic characterization of industrial effluents in the environment has become more and more recognized. A palette of different analytical methods both for sample...
Artelt, S., Creutzenberg, O., Kock, H., Levsen, K., Nachtigall, D., Heinrich, U., ...
Automobile exhaust catalytic converters emit fine dispersed elemental platinum, Pt(0), in the nanometer range coated on larger aluminium oxide carrier particles. A pre-requisite for a potential...
Artelt, S., Kock, H., Levsen, K., Rosner, G.
Depending on the operating conditions and the age of the converter, mean platinum emissions ranged from 7 to 123 ng m-3 corresponding to emission factors between 9 and 124 ng km-1. There were no...
Former ammunition plants endanger the environment and mankind at many sites. Especially the groundwater at former ammunition plants is contaminated by explosives and related compounds. For sanitation...
Die Innenraumsituation nach einer Schädlingsbekämpfungsmaßnahme: Eine Langzeitstudie (1998)
Im unmittelbaren Lebensbereich des Menschen werden zum Schutz gegen Schädlinge und damit zum Schutz gegen die Übertragung von Krankheitserregern häufig Pyrethroide eingesetzt. Dabei kann eine...
Die kontinuierliche Überwachung organischer Inhaltsstoffe im Zu- und Ablauf industrieller Kläranlagen ist wünschenswert, um möglichst frühzeitig erhöhte Konzentrationen zu erkennen. So kann z....
Levsen, K., Wichmann, H.E., Heinrich, J., Angerer, J., Ilgen, E., Karfich, N., ...
Die Luft in nicht gewerblich genutzten Innenräumen ist durch eine Vielzahl von flüchtigen organischen Verbindungen ("volatile organic compunds = VOCs") belastet, die oftmals in wesentlich höheren...
Godejohann, M., Preiß, A., Levsen, K., Mügge, C.
Leachate, ground-, and surface water from former ammunition sites and areas which are known to be contaminated by nitroaromatic compounds in Lower Saxony (Germany) were investigated in order to...
The great dun fell cloud experiment 1993: An overview (1997)
Choularton, T.W., Colvile, R.N., Bower, K.N., Gallagher, M.W., Wells, M., Beswick, K.M., ...
The 1993 Ground-based Cloud Experiment on Great Dun Fell used a wide range of measurements of trace gases, aerosol particles and cloud droplets at five sites to study their sources and sinks...
Phase partitioning of phenol and nitrophenols in clouds (1997)
During five different cloud events at the summit of Great Dun Fell (GDF) the gas and liquid phases of clouds were collected simultaneously. Phenol, 2-nitrophenol (2-NP), 4-nitrophenol (4-NP),...
Occurence and formation of nitrated phenols in and out of cloud (1997)
Lüttke, J., Scheer, V., Levsen, K., Wünsch, G., Cape, J.N., Hargreaves, K.J., ...
In this study, the concentrations of phenol, four nitrated phenols, their precursors and reactants in air and cloud water, are presented. The concentrations in air and cloud water were measured...
Identification of pollutants in ammunition hazardous waste sites by thermospray HPLC/MS (1997)
Astratov, M., Preiß, A., Levsen, K., Wünsch, G.
HPLC/MS using thermospray ionization (TSP) was applied to identify and quantify explosives and other pollutants in groundwater samples of an ammunition hazardous waste site, where mainly TNT...
40 rainwater samples were collected in Hannover and near Peine (Lower Saxony, Germany) in 1992 using a wet-only collector. The samples were extracted by solid phase extraction and analyzed by GC/MS...
The behaviour of pyrethroids indoors: A model study (1997)
Berger-Preiß, E., Preiß, A., Sielaff, K., Raabe, M., Ilgen, B., Levsen, K.
Pest control agents containing three different formulations of the pyrethroids permethrin and deltamethrin and/or pyrethrines and the synergist piperonyl butoxide were applied in a model house...
Atmospheric nitration of phenols in clouds by N2O5 and ClNO2: Guest contribution (1997)
Scheer, V., George, C., Lüttke, J., Levsen, K., Behnke, W., Frenzel, A., ...
Conclusions: Nitrophenols can be formed from phenols in the troposphere during night time chemistry by reaction involving NO2+ in the aqueous phase (clouds, fog, deliquescent sea spray). Other...
Analysis of individual natural pyrethrins in indoor matrices by HRGC/ECD (1997)
Berger-Preiß, E., Preiß, A., Levsen, K.
An HRGC/ECD method is presented which permits the identification and quantitation of individual components of pyrethrins (cinerin I, jasmolin I, pyrethrin I, cinerin II, jasmolin II, pyrethrin II) in...
Die Kenntnisse hinsichtlich Entstehung und Vorkommen von organischen Spurenstoffen in der Troposhäre, insbesondere in Wolkenwasser und Wolkengasphase (Interstitialluft), sind lückenhaft. Ziel...
Methods developed for the analysis of organic compounds from aqueous samples by solid-phase microextraction (SPME) coupled to gas chromatography (GC) are reviewed with special emphasis on the...
A prototype of an analytical system allowing the quasi-continuous monitoring of organic contaminants in surface water which should be also applicable to the analysis of sewage water was developed. It...
Levsen, K., Liebisch, A., Dyck, A.
Im Rahmen der Studie wurde das Verhalten von Schädlingsbekämpfungsmitteln, die zur Verbindungsklasse der Pyrethroide bzw. Pyrethrine gehören, sowie des Synergisten Piperonylbutoxid nach...
The aim of this work was the development of sampling devices and sampling and analysis methods for the determination of organic compounds in the different phases of clouds with the goal of attaining...
Godejohann, M., Preiß, A., Levsen, K., Wünsch, G., Eisert, R.
An HPLC method with diode array detection for the determination of acide aromatic nitro compounds (in particular nitrophenols and nitrobenzoic acids) in ground water around former ammunition plants...
Preiß, A., Levsen, K., Humpfer, E., Spraul, M.
High-field proton nuclear magnetic resonance (1H-NMR) spectroscopy was applied to the analysis of nitroaromatics and nitramines in ammunition waste water. The 1H-chemical shifts data of a variety of...
Indoor exposure to Pyrethroid insecticides (1996)
Berger-Preiß, E., Preiß, A., Levsen, K.
The contamination of rooms after application of pyrethroid insecticides was investigated in this study. Three different formulations containing deltamethrin, permethrin, piperonylbutoxide and...
Solid-phase microextraction (SPME) represents a very simple and rapid method for the extraction of organophosphorus, triazine and 2,6-dinitroaniline pesticides from aqueous samples without making use...
A multiresidue method was developed for the determination of nitrogen- and phosphorous-containing pesticides (amines, anilides, phosphorothioates, and triazines) by solid-phase microextraction (SPME)...
Einsatz der SPME zur Bestimmung von Pestiziden in wäßrigen Umweltproben (1995)
Solid-phase microextraction (SPME) is evaluated with respect to its suitability to GC analysis of a large spectrum of pesticides having a wide range of structures and polarities. Organophosphorus and...
Determination of nitrophenols, diaminotuluenes, and chloroaromatics in ammunition wastewater (1995)
Mußmann, P., Levsen, K., Wünsch, G., Eisert, R.
Methods for the determination of three compound classes, i.e. diaminotoluenes, nitrophenols, and chloroaromatics in groundwater of a former ammunition plant are reported. Diaminotoluenes were...
Heinrich, U., Fuhst, R., Rittinghausen, S., Creutzenberg, O., Bellmann, B., Koch, W., ...
Wistar rats were exposed for 2 yr to diesel engine exhaust, carbon black, and ultrafine TiO2 and were subsequently kept in clean air for 6 mo. Particle exposure concentration was increased during the...
Sennert, S., Volmer, D., Levsen, K., Wünsch, G.
In the search for a fast and robust sample handling and preparation step to analyse various pesticides at trace levels in aqueous samples, an on-line trace enrichment has been combined with out...
Volmer, D., Levsen, K., Wünsch, G.
Thermospray (TSP) ionization was evaluated with respect to its suitability in the LC-MS determination of a broad range of pesticides. The sensitivity and the selectivity of this method for the...
For the first time photochemical transformation products of a wide variety of pesticides discovered in the atmosphere. 28 photochemical reaction products, resulting from 12 pesticides, were...
Simultaneously collected cloud aqueous and gas phase samples of the Great Dun Fell experiment were analysed for phenol and several nitrophenols. Phenol, 2-nitrophenol, 2,4-dinitrophenol,...
Mußmann, P., Preiß, A., Levsen, K., Wünsch, G.
Gas chromatography and high performance liquid chromatography were used to determine explosives, their by- and degradation products near the former ammunition plant Elsnig in Saxony. Enrichment...
A series of nitrogen- and phosphorus-containing pesticides (amines, anilides, carbamates, phosphonates, phenylureas, sulfonylureas, and triazines) was examined by thermospray (TSP) ionization. A...
Sollinger, S., Levsen, K., Wünsch, G.
The emission of organic compounds from textile floor coverings was studied in a climate test chamber under static conditions (zero air exchange) in order to test the parameters which influence such...
Gas-chromatographic determination of phenols in aqueous samples after solid phase extraction (1994)
Mußmann, P., Levsen, K., Radeck, W.
27 phenols including mono- di-, tri-, tetra- and pentachlorophenols, mono- and dinitrophenols, mono- and dinitrocresols and dimethylnitrophenols have been extracted from aqueous samples by solid...
Berger-Preiß, E., Preiß, A., Levsen, K.
The objective of the present study is to investigate the contamination of indoor rooms after using indoor insecticides in different application forms. This is necessary in order to evaluate a...
Berger-Preiß, E., Preiß, A., Levsen, K.
The objective of the present study is to investigate the contamination of indoor rooms after using indoor insecticides in different application forms. This is necessary in order to evaluate a...
Eisert, R., Levsen, K., Wünsch, G.
The analysis of samples contaminated by organic compounds, especially pesticides, is an important tool of environmental monitoring. A new isolation method has been developed for the determination of...
Berger-Preiß, E., Preiß, A., Levsen, K.
The objective of the present study is to investigate the contamination of indoor rooms after using indoor insecticides in different application forms. This is necessary in order to evaluate a...
Heinrich, U., Dungworth, D.L., Pott, F., Peters, L., Dasenbrock, C., Levsen, K., ...
Carbon black (CB) particles almost completely devoid of organic compounds (Printex 90, Degussa), PAH-rich hard coal tar-pitch condensation aerosol (T-P aerosol) and mixtures of CB and T-P aerosol as...
Volmer, D., Levsen, K., Engewald, W.
Thermospray ionization was evaluated with respect to its suitability in the HPLC-MS determination of large number of pesticides having a wide range of structures and polarities in aqueous...
Organische Innenraumluftverunreinigungen aus textilen Bodenbelägen: Abschlußbericht (1993)
Im vorliegenden Forschungsvorhaben wurden Analysenmethoden und Prüfverfahren entwickelt, die die Identifizierung und Quantifizierung von flüchtigen organischen Emissionen aus textilen Bodenbelägen...
Textile floor coverings as sinks for indoor air pollutants (1993)
Climate chamber studies have been used to demonstrate that textile floor coverings act as efficient sinks for volatile organic compounds (VOCs) found in the indoor environment. A model was developed...
Temperature and salt concentration effects on the ion abundances in thermospray mass spectra (1993)
Volmer, D., Preiß, A., Levsen, K., Wünsch, G.
The dependence of the ion abundances in the thermospray (TSP) mass spectra of several pesticides, including anilides, carbamates, N-heterocyclic and organophosphorus compounds and phenylureas on the...
Scavenging of organic compounds by cloud droplets. Contribution to subproject ACE (1993)
While the scavenging of inorganic gases as well as inorganic compounds adsorbed on particles by cloud droplets have been studied extensively only a few investigations have dealt with the analysis of...
Organic compounds in cloud and rain water (1993)
Levsen, K., Behnert, S., Mußmann, P., Raabe, M., Prieß, B.
Cloud and rain water samples have been collected in spring 1991 in the Vosges mountains and analyzed for aldehydes, phenols and polycyclic aromatic hydrocarbons (PAH). Both passive and active cloud...
There are many sources which may contribute to the contamination of indoor air, especially by organic compounds. Emissions from building materials are of particular importance. As these different...
Sollinger, S., Levsen, K., Wünsch, G.
The time dependence of the emission of organic compounds from a polyamide with styrene-butadiene-rubber (SBR) backing was studied in three climate chambers. While volatile compounds such as toluene...
Determination of organic emissions from textile floor coverings (1993)
Sollinger, S., Behnert, S., Levsen, K.
The organic emissions from textile floor coverings have been investigated in a climate chamber under static and dynamic conditions. 110 compounds have been identified as emission products, the origin...
Levsen, K., Emmrich, M., Behnert, S.
A method for the extraction and clean-up of four groups of cationic surfactants in sewage water and activated sludge is reported. In the case of sewage water, this is based on the extraction of the...
Levsen, K., Mußmann, P., Berger-Preiß, E., Preiß, A., Volmer, D., Wünsch, G.
Waste water from ammunition production sites and aqueous samples on or near former military sites on which explosives were produced or filled may be contaminated by the original explosives but also...
Levsen, K., Mußmann, P., Berger-Preiß, E., Preiß, A.
Waste water from ammunition production sites and aqueous samples on or near former military sites on which explosives were produced or filled may be contaminated by the original explosives but also...
Volmer, D., Preiss, A., Levsen, K., Wünsch, G.
The dependence of the ion abundances in the thermospray (TSP) mass spectra of several pesticides, including anilides, carbamates, N-heterocyclic and organophosphorus compounds and phenylureas on the...
Das Verhalten faserverstärkter Kunststoffe beim Laserschneiden (1992)
The pattern of organic emissions, which are produced by processing of fiber reinforced plastics with laser beam was studied and the concentrations of the main components determined. Despite the...
A climate test chamber of 1 m3 volume for the determination of the emission of volatile organic compounds (VOCs) from building materials is presented. The chamber allows to vary the temperature and...
Methoden zur Charakterisierung der Emissionen aus textilen Bodenbelägen (1992)
Die Emissionen organischer Verbindungen aus Polyamidteppichböden mit Styrol-Butadien-Gummirücken, die 80 % des Marktanteils an textilen Bodenbelägen in der Bundesrepublik ausmachen, wurden mit...
Method development for the analysis of pesticides on a nitrophenol basis (1992)
Efer, J., Engewald, W., Levsen, K., Mußmann, P., Preiß, A., Wünsch, G.
Pesticides on a nitrophenol basis and nitrophenols which may be formed by biotransformation from other plant-protecting agents may be extracted from aqueous samples with high recoveries by continuous...
Emmrich, M., Levsen, K., Sollinger, S.
A method for the determination of organic acids in ambient air using an ion-exchange resin in a bifunctional manner is presented. The ion-exchange resin is used as an adsorbent for sampling and...
The contamination of precipitation in Hannover by hydrocarbons (1992)
Behnert, S., Levsen, K., Prieß, B.
In 1989 and 1990 precipitation (mainly rain) was collected in Hannover (Niedersachsen, Germany) and analyzed for aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs). Seasonal...
Organic emissions during laser cutting of fibre-reinforced plastics. (1991)
Emmrich, M., Kock, H., Levsen, K., Prieß, B., Sollinger, S.
During laser cutting of fibre-reinforced plastics (i.e. epoxy resins reinforced by aramide-, glass- or carbon fibres, phenol resins reinforced by aramide fibres, polyester, polyurethane and polyamide...
Organic compounds in precipitation (1991)
Behnert, S., Levsen, K., Winkeler, H.D.
Precipitation samples collected in Hannover (Germany) mainly in 1989 (and in part also in 1988 and 1990) were analyzed for n-alkanes, fatty acids, aldehydes, phenols and polycyclic aromatic...
Rummenhöller, S., Busch, H., Holländer, W., Levsen, K.
Laser beam cutting and milling of fibre reinforced plastics leads to high emissions of smoke and dust. For laser beam cutting the health risk is mainly determined by the very high fine dust...
Analyse der Emissionen beim Laserstrahlschneiden faserverstärkter Kunststoffe (1991)
Busch, H., König, W., Levsen, K.
Laser beam cutting of fibre-reinforced plastics leads to high emissions of smoke and dust. This may cause a health risk for machinery operators due to high inhalable dust concentrations. Also, the...
From July to December 1989 22 rain water samples were collected in Hannover (F.R. Germany) and analyzed for phenol, 2-methylphenol, 3-/4-methylphenol, 2-nitrophenol and 4-nitrophenol by combined...
Organic compounds in precipitation (1990)
Behnert, S., Levsen, K., Prieß, B., Svoboda, M., Zietlow, J.
Precipitation (mainly rain) has been collected in Hannover (Germany) in 1989 and 1990 and analyzed for n-alkanes, fatty acids, n-alkanols, aldehydes, phenols and polycyclic aromatic hydrocarbons...
Kationische Tenside im Abwasser und Belebtschlamm (1990)
In waste water and activated sludge, cationic surfactants are often measured as disulfine blue active substances. Because of the suspectibility of this method to interfering substances a more...
Gas chromatography and mass spectrometric determination of nitroaromatics in water (1990)
Volmer, D., Spiekermann, M., Feltes, J., Levsen, K.
Several methods for the extraction of nitroaromatic compounds from water were compared. High recoveries were achieved with discontinuous or continuous extraction of water with dichloromethane and by...
Der Eintrag organischer Verbindungen in den Boden durch Niederschläge (1990)
Behnert, S., Levsen, K., Prieß, B., Zietlow, J.
Precipitation samples collected in Hannover in 1990/91 were analyzed for various organic compound classes: Formaldehyde, acetaldehyde, propionaldehyde, n-alkanes from n-C18H38 to n-C33H68, polycyclic...
Samples containing nitroaromatics have been taken from brooks and ponds in former ammunition production areas in Hessia (FRG) and Lower Saxony (FRG). The compounds were extracted by solid/liquid...
Winkeler, Heinz-D., Levsen, K., Winkeler, H.D.
Derivatization of nitrophenols in water with pentafluorobenzoyl chloride by gas chromatographic determination with electron capture detection is achieved by a phase transfer reaction using...
Low molecular weight organic acids in rain water. (1989)
Winkeler, Heinz-D., Levsen, K., Winkeler, H.D.
Recent studies demonstrated that rain water may be heavily polluted by organic compounds including low molecular weight organic acids. In the past such acids were predominantly determined by...
Böhm, H.B., Volmer, D., Feltes, J., Levsen, K.
Nitrophenols were extracted from rain-water with dichloromethane in two steps. Isocratic separation by high-performance liquid chromatography was achieved with methanol-phosphate buffer (40:60) at pH...
Solid phase extraction is used to clean-up diesel particulate extracts for an identification of nitrated polycyclic hydrocarbons (nitro-PAHs). Thirty eight nitro-PAHs were identified both by electron...
Determination of nitrophenols in rain and snow. (1989)
Alber, M., Böhm, H.B., Brodesser, J., Schöler, H.F., Feltes, J., Levsen, K.
Nitrophenols have been determined in rain collected in Hannover (F. R. Germany) over a period of 9 months in 1988 and in snow collected in Northrhine-Westphalia (F. R. Germany) in February and March...
Winkeler, Heinz-D., Levsen, K., Schilhabel, J., Winkeler, H.D.
Today polycyclic aromatic hydrocarbons (PAH) in many environmental sample such as surface water and urban particulate are frequently analyzed by high performance liquid chromatography (HPLC) (1). On...
Progress in the analysis of diesel soot particles (1988)
Levsen, K., Puttins, U., Schilhabel, J.
Diesel particulate extracts have been characterized by HPLC and mass spectrometry. PAH were determined with HPLC and fluorescence detection. Nitrated PAH were characterized by tandem mass...
Organische Verbindungen im Regenwasser (1988)
Levsen, K., Puttins, U., Winkeler, H.D.
Am Stadtrand von Hannover wurde Regenwasser gesammelt und auf organische Inhaltsstoffe hin untersucht. Es konnten höhere n-Alkane, polycyclische aromatische Kohlenwasserstoffe (PAH) und ihre...
Mass spectrometry in environmental organic analysis (1988)
The use of mass spectrometry in environmental analysis is reviewed with special emphasis on modern mass spectrometric methods. (ITA)
Artefacts during the sampling of nitro PAHs of diesel exhaust (1988)
Levsen, K., Puttins, U., Schilhabel, J., Prieß, B.
If diesel particulate is collected on glass fiber filters during a period of 23 min (one US 72 cycle) 13, 6+- 9,5% of the 1-nitropyrene is formed as artefact on the filter. (ITA)
The analysis of diesel particulate (1988)
Methods developed for the analysis of the organic compounds adsorbed on diesel particulate are reviewed with special emphasis on the determination of polycyclic aromatic hydrocarbons (PAH), nitro PAH...
Mit Hilfe der Felddesorptionsmassenspektrometrie wurde der biologische Abbau von Nonylphenolethoxylat (NPE) und Ditalgfettdimethylammoniumchlorid (DTDMAC) in Flusswasser untersucht. NPE wird...
Frensch, K., Hahn, J.U., Levsen, K., Nießen, J., Schöler, H.F., Schoenen, D.
In einem Trinkwasserbehaelter war nach einem Anstrich mit loesemittelhaltigem Bitumen ein Koloniezahlanstieg beobachtet worden. Durch eine Hochchlorung konnte die Kaloriezahl wieder reduziert werden....
Frensch, K., Hahn, J.U., Levsen, K., Nießen, J., Schöler, H.F., Schoenen, D.
In einem Trinkwasserbehaelter war nach einem Anstrich mit loesemittelhaltigem Bitumen ein Koloniezahlanstieg beobachtet worden. Durch eine Hochchlorung konnte die Koloniezahl wieder reduziert werden....
On the formation of C2H5O2+ ions having the structure of hydroxy-protonated acetic acid (1984)
Terlouw, J.K., Koster, C.G. De, Levsen, K.
Experiments are reported which are best explained in terms of the formation of the long-sought hydroxy-protonated acetic acid, CH3C(O)OH2- This C2 H5O2+ species, generated upon dissociative...
Organic compounds in clouds (1982)
Lüttke, J., Koch, C., Mußmann, P., Levsen, K.
A method for the analysis of organic compounds in the gas- and liquid phase of clouds is reported. The liquid phase is collected with a high volume-flow impactor. The gas phase is sampled with four...