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The antimicrobial and wear behaviour of metallic glass composites corresponding to the Cu(ZrAl) system with x = (0, 3 and 6) has been studied. The three compositions consist of crystalline phases embedded in an amorphous matrix and they exhibit crystallinity increase with increasing Cu content, i.e., decrease of the glass-forming ability. The wear resistance also increases with the addition of Cu as indirectly assessed from H/E and H/E parameters obtained from nanoindentation tests. These results are in agreement with scratch tests since for the alloy with highest Cu content, i.e., CuZrAl, reveals a crack increase, lower pile-up, prone adhesion wear in dry sliding and higher scratch groove volume to pile-up volume. Samples with higher Cu content revealed higher hydrophilicity. Time-kill studies revealed higher reduction in colony-forming units for E. coli (gram-negative) and B. subtilis (gram-positive) after 60 min of contact time for the CuZrAl alloy and all the samples achieved a complete elimination of bacteria in 250 min.

Positive ion mobility spectra of n-alkanes (n-C-5 to n-C-19), branched chain alkanes (C-5 to C-9) and aromatic compounds (benzene and alkylated benzenes) were acquired with an ion mobility spectrometer equipped with a corona discharge ionization source. Reduced mobilities and mass-to-mobility correlation curves were determined for these compounds. Depending on their concentration, the n-alkanes form one or two product ion peaks. The mobilities of product ion peaks regularly decrease with increasing chain length. The same behavior was observed for branched chain alkanes. However, characteristic fragment ions are additionally formed in comparison with n-alkanes. The investigated aromatic hydrocarbons show simple spectra consisting of up to three;characteristic product ion peaks. The obtained mass-to-mobility correlation curve differs from that determined using photoionization.

Positive ion mobility spectra of chlorobenzene, bromobenzene and iodobenzene were measured using different ionization processes. Corona discharge ionization and photoionization permit a more sensitive detection of these compounds in comparison with 63Ni ionization. For chlorobenzene and bromobenzene, a similar drift behavior of formed product ions can be observed. Corona discharge ionization and photoionization provide one product ion peak. However, the reduced mobility values (K0 values) vary depending on the used ionization method. For 63Ni ionization, two product ion peaks are detected for these compounds. The reduced mobility values of these two peaks correspond to K0 values of the peaks observed by corona discharge ionization and photoionization. For iodobenzene, two peaks can be obtained for all ionization processes. However, the most intensive peak is detected at the same reduced mobility values for all ionization processes.

Corona discharge ion mobility spectrometry permits the determination of n-alkanes and branched chain alkanes within the low ppm range. For n-alkanes, one or two product ion peaks are observed. Two product ion peaks are detectable in lower concentration range only (<30-45 ppm in dependence on physical and chemical properties of n-alkanes). With increasing concentrations, the ion mobility spectra show one product ion peak with a sharp peak profile. The reduced mobilities of these peaks decrease regularly with increasing molecular weight. Series of product ion peaks are obtained for branched chain alkanes. Characteristic fragment ions are additionally formed in comparison with n-alkanes.

Mobile analysis is, in most cases, the use of transportable, classical analytical techniques combined with fast and simple methods of sample preparation. This paper presents the overall configuration of such a mobile laboratory.Rapid sample turnaround, that results from onsite analytical methods, permits the optimization of sampling positions and, by using geostatistical methods, data interpretation under field conditions.Some of the different techniques for sample preparation are described. The most effective analytical techniques for multicomponent detection are gas chromatography coupled with mass spectrometry (GC/MS) and energy dispersive X-ray fluorescence spectrometry (EDXRF). Both techniques are installed in the mobile laboratory of the CER along with fast sample preparation techniques. The instruments used, as well as some of the results of the investigations of waste sites with the mobile analysis are demonstrated. The results and the advantages of the different methods are also discussed. &nbsp

Ion mobility spectrometry (IMS) has become one of the most interesting on-site methods during the last years. This trend is mainly caused by typical advantages of this technique that offers high sensitivity, instrumental simplicity, low cost, analytical flexibility, and real time monitoring capability [1]. Small hand-held and easy-to-use instruments are available on the market. However, the application of ion mobility spectrometers for on-site analyses requires miniaturized, simple and fast sample preparation techniques as well. In addition, most of the samples like old deposited wastes which have to be analyzed on site consist of complex mixtures. Due to the complex reaction mechanisms known for ß or photo ionization, the evaluation of IMS spectra of mixtures is complicated or impossible in many cases. For this reason special attention has to be paid to the coupling of IMS with gas chromatography or other separation methods. The GC/IMS coupling leads to a significant increase of applications of ion mobility spectrometry especially in the case of on-site analyses. Not least on-site methods require a flexible spectrometer and a data processing software.

Der partikelgebundene Schadstoffeintrag hat im Ballungsgebiet Leipzig-Halle-Bitterfeld auf Grund der enormen Staubmengen, die über Jahrzehnte hier sedimentierten, eine traditionell große Bedeutung. Die Konzentrationen organischer Verbindungen in Sedimentationsstäuben, z.B. polycyclische aromatische Kohlenwasserstoffe (PAK), polychlorierte Aromaten, Biphenyle (PCB) und polychlorierte Dibenzodioxine und -furane (PCDD/PCDF), wurden im Zeitraum von 1987 bis 1992 an verschiedenen Punkten des Ballungsgebietes gemessen. Bis 1989 wurden in den industriellen Zentren Leipzig und Bitterfeld monatliche Staubmengen zwischen 5 g/m1 und 12 g/m2 registriert. Seit 1990, dem Jahr des wirtschaftlichen und politischen Strukturwandels, verringerte sich die Staubbelastung um das Zwei- bis Dreifache. Auf Grund dessen erhöhten sich die Konzentrationen organischer Verbindungen in den Stäuben. Durch die geringere Staubbelastung geht der Schadstoffeintrag seit diesem Zeitpunkt jedoch zurück. Über den gesamten Zeitraum zeigt sich eine starke Differenzierung des organischen Schadstoffeintrages. The territory of Leipzig-Halle-Bitterfeld is considered as the area of the former GDR, which was highest contaminated with organic and inorganic compounds. This fact stimulated a detailed investigation of dry depositions sampled at different sites of this area between 1987 and 1992. Depositions polyaromatic hydrocarbons, polychlorinated aromatics, biphenyls and dioxines were determined. Since 1990, the year of political and industrial change, the level of particular deposition is two to three times lower. The concentration of organic compounds in the sedimented·dust increases since that time. The deposition of organic pollutions decreases due to a decreasing amount of dust. Large differences in organic particulate pollution levels have been measured at different positions of the area.

The Espenhain mine, south of Leipzig was one of the industrial centers of coal processing in the former GOR. In this area selected organic compounds were analyzed in different used soils. Samples were taken at different distances from the industrial emitters. The concentrations of most organic compounds stemming from processing ofbrown coal decrease rapidly with increasing distance from main emitters. In dependence an the different use of soils considerable differences of concentrations were found. The determinated concentrations of some organic compounds are higher than current critical values.