TY  - GEN
A1  - Brinkmann, Pia
A1  - Köllner, Nicole
A1  - Merk, Sven
A1  - Beitz, Toralf
A1  - Altenberger, Uwe
A1  - Löhmannsröben, Hans-Gerd
T1  - Comparison of handheld and echelle spectrometer to assess copper in ores by means of laser-induced breakdown spectroscopy (LIBS)
T2  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Its properties make copper one of the world’s most important functional metals. Numerous megatrends are increasing the demand for copper. This requires the prospection and exploration of new deposits, as well as the monitoring of copper quality in the various production steps. A promising technique to perform these tasks is Laser Induced Breakdown Spectroscopy (LIBS). Its unique feature, among others, is the ability to measure on site without sample collection and preparation. In this work, copper-bearing minerals from two different deposits are studied. The first set of field samples come from a volcanogenic massive sulfide (VMS) deposit, the second part from a stratiform sedimentary copper (SSC) deposit. Different approaches are used to analyze the data. First, univariate regression (UVR) is used. However, due to the strong influence of matrix effects, this is not suitable for the quantitative analysis of copper grades. Second, the multivariate method of partial least squares regression (PLSR) is used, which is more suitable for quantification. In addition, the effects of the surrounding matrices on the LIBS data are characterized by principal component analysis (PCA), alternative regression methods to PLSR are tested and the PLSR calibration is validated using field samples.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1311 
KW  - LIBS
KW  - copper-bearing minerals
KW  - UVR
KW  - PCA
KW  - PLSR
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-584742
SN  - 1866-8372
IS  - 1311
ER  - 
TY  - JOUR
A1  - Schirmack, Janosch
A1  - Boehm, Michael
A1  - Brauer, Chris
A1  - Löhmannsröben, Hans-Gerd
A1  - de Vera, Jean-Pierre Paul
A1  - Moehlmann, Diedrich
A1  - Wagner, Dirk
T1  - Laser spectroscopic real time measurements of methanogenic activity under simulated Martian subsurface analog conditions
JF  - Planetary and space science
N2  - On Earth, chemolithoautothrophic and anaerobic microorganisms such as methanogenic archaea are regarded as model organisms for possible subsurface life on Mars. For this reason, the methanogenic strain Methanosarcina soligelidi (formerly called Methanosarcina spec. SMA-21), isolated from permafrost-affected soil in northeast Siberia, has been tested under Martian thermo-physical conditions. In previous studies under simulated Martian conditions, high survival rates of these microorganisms were observed. In our study we present a method to measure methane production as a first attempt to study metabolic activity of methanogenic archaea during simulated conditions approaching conditions of Mars-like environments. To determine methanogenic activity, a measurement technique which is capable to measure the produced methane concentration with high precision and with high temporal resolution is needed. Although there are several methods to detect methane, only a few fulfill all the needed requirements to work within simulated extraterrestrial environments. We have chosen laser spectroscopy, which is a non-destructive technique that measures the methane concentration without sample taking and also can be run continuously. In our simulation, we detected methane production at temperatures down to -5 degrees C, which would be found on Mars either temporarily in the shallow subsurface or continually in the deep subsurface. The pressure of 50 kPa which we used in our experiments, corresponds to the expected pressure in the Martian near subsurface. Our new device proved to be fully functional and the results indicate that the possible existence of methanogenic archaea in Martian subsurface habitats cannot be ruled out. (C) 2013 Published by Elsevier Ltd.
KW  - Mars
KW  - Methanogens
KW  - Methane
KW  - Sub-zero temperature (Celsius)
KW  - Wavelength modulation spectroscopy (laser spectroscopy)
Y1  - 2014
U6  - https://doi.org/10.1016/j.pss.2013.08.019
SN  - 0032-0633
VL  - 98
SP  - 198
EP  - 204
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - CHAP
A1  - Lück, Erika
A1  - Balderjahn, Ingo
A1  - Kamm, Birgit
A1  - Greil, Holle
A1  - Wallschläger, Hans-Dieter
A1  - Jessel, Beate
A1  - Böckmann, Christine
A1  - Oberhänsli, Roland
A1  - Soyez, Konrad
A1  - Schmeer, Ernst
A1  - Blumenstein, Oswald
A1  - Berndt, Klaus-Peter
A1  - Edeling, Thomas
A1  - Friedrich, Sabine
A1  - Kaden, Klaus
A1  - Scheller, Frieder W.
A1  - Petersen, Hans-Georg
A1  - Asche, Hartmut
A1  - Bronstert, Axel
A1  - Giest, Hartmut
A1  - Gaedke, Ursula
A1  - Löhmannsröben, Hans-Gerd
A1  - Jeltsch, Florian
A1  - Jänkel, Ralph
A1  - Gzik, Axel
A1  - Bork, Hans-Rudolf
A1  - Bork, Hans-Rudolf
T1  - Umweltforschung für das Land Brandenburg : Arbeitsgruppen und Professuren
Y1  - 2000
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-3797
ER  -