List of works - Frank Keppler

A stable isotope approach to assessing water loss in fruits and vegetables during storage.

scientific article published on 12 February 2015

Abiotic methanogenesis from organosulphur compounds under ambient conditions

scientific article

Abiotic methyl bromide formation from vegetation, and its strong dependence on temperature

scientific article published on 01 September 2008

Age dependent breath methane in the German population

scientific article published on 12 March 2014

Aquatic and terrestrial cyanobacteria produce methane

scientific article published on 15 January 2020

Canadian Arctic Neogene Temperatures Reconstructed From Hydrogen Isotopes of Lignin‐Methoxy Groups From Sub‐Fossil Wood

scientific article published in 2022

Carbon, hydrogen and oxygen stable isotope ratios of whole wood, cellulose and lignin methoxyl groups ofPicea abiesas climate proxies

scientific article published on 01 January 2013

Chloride methylation by plant pectin: an efficient environmentally significant process.

scientific article

Chlorine Isotope Fractionation of the Major Chloromethane Degradation Processes in the Environment

scientific article published on 17 January 2020

Chloromethane Degradation in Soils: A Combined Microbial and Two-Dimensional Stable Isotope Approach

scientific article published in 2018

Chloromethane emissions in human breath.

scientific article

Chloromethane formation and degradation in the fern phyllosphere

scientific article published in September 2018

Chloromethane release from carbonaceous meteorite affords new insight into Mars lander findings.

scientific article

Climate signals in stable carbon and hydrogen isotopes of lignin methoxy groups from southern German beech trees

scientific article published in 2022

Comment on Authenticity and traceability of vanilla flavors by analysis of stable isotopes of carbon and hydrogen

scientific article published on 22 May 2015

De novo formation of chloroethyne in soil.

scientific article published in January 2006

Design and application of a synthetic DNA standard for real-time PCR analysis of microbial communities in a biogas digester.

scientific article published on 20 June 2015

Differentiation of the halogen content of peat samples using ion chromatography after combustion (TX/TOX-IC).

scientific article published on 25 February 2003

Effects of Temperature and Light on Methane Production of Widespread Marine Phytoplankton

scientific article published in 2020

Enhanced formation of methane in plant cell cultures by inhibition of cytochrome c oxidase.

scientific article published on 15 December 2010

Evidence for a major missing source in the global chloromethane budget from stable carbon isotopes

scientific article published in 2019

Evidence for methane production by saprotrophic fungi.

scientific article

Evidence for methane production by the marine algae &lt;i&gt;Emiliania huxleyi&lt;/i&gt;

scientific article published in 2016

Evidence of anaerobic syntrophic acetate oxidation in biogas batch reactors by analysis of 13C carbon isotopes.

scientific article

Exogenous addition of H2 for an in situ biogas upgrading through biological reduction of carbon dioxide into methane.

scientific article published on 13 June 2017

Fluxes of trichloroacetic acid between atmosphere, biota, soil, and groundwater ⬇️

scientific article published on July 1, 2003

Formation of chloroacetic acids from soil, humic acid and phenolic moieties ⬇️

scientific article published on July 1, 2003

Formation of volatile iodinated alkanes in soil: results from laboratory studies.

scientific article published in July 2003

Halocarbons produced by natural oxidation processes during degradation of organic matter.

scientific article published on January 2000

Halogen retention, organohalogens, and the role of organic matter decomposition on halogen enrichment in two Chilean peat bogs.

scientific article published in April 2004

High Spatiotemporal Dynamics of Methane Production and Emission in Oxic Surface Water

scientific article published on 22 January 2020

Hydrogen and carbon isotope fractionation during degradation of chloromethane by methylotrophic bacteria

scientific article published on 8 September 2013

Identification of methanogenic pathways in anaerobic digesters using stable carbon isotopes

Isotopic composition of H2from wood burning: Dependency on combustion efficiency, moisture content, andδD of local precipitation

article

Late permian changes in conditions of the atmosphere and environments caused by halogenated gases

Long-term monitoring of breath methane

scientific article

Mean annual temperatures of mid-latitude regions derived from δ(2)H values of wood lignin methoxyl groups and its implications for paleoclimate studies.

scientific article

Measurements of 13C/12C methane from anaerobic digesters: comparison of optical spectrometry with continuous-flow isotope ratio mass spectrometry

scientific article

Methane emissions from terrestrial plants under aerobic conditions.

scientific article

Methane formation in aerobic environments

Methane oxidation in industrial biogas plants - insights in a novel methanotrophic environment evidenced by pmoA gene analyses and stable isotope labelling studies.

scientific article published on 3 February 2018

Methane production by three widespread marine phytoplankton species: release rates, precursor compounds, and potential relevance for the environment

scientific article published in 2019

Methoxyl groups of plant pectin as a precursor of atmospheric methane: evidence from deuterium labelling studies.

scientific article

Methyl chloride emissions from halophyte leaf litter: Dependence on temperature and chloride content

scientific article published on 04 January 2012

Methyl sulfates as methoxy isotopic reference materials for δ13 C and δ2 H measurements

scientific article published on 01 February 2019

Nitrous oxide and methane emissions from cryptogamic covers.

scientific article published on 7 July 2015

Nitrous oxide effluxes from plants as a potentially important source to the atmosphere

article

Non-microbial methane formation in oxic soils

scientific article published in 2012

Nonheme Iron-Oxo-Catalyzed Methane Formation from Methyl Thioethers: Scope, Mechanism, and Relevance for Natural Systems

scientific article published on 7 June 2017

Online monitoring of stable carbon isotopes of methane in anaerobic digestion as a new tool for early warning of process instability.

scientific article published on 21 August 2015

Organic compounds in fluid inclusions of Archean quartz-Analogues of prebiotic chemistry on early Earth.

scientific article

Peatlands: a major sink of naturally formed organic chlorine

scientific article published on 01 July 2003

Position-specific isotope analysis of the methyl group carbon in methylcobalamin for the investigation of biomethylation processes

scientific article

Potential role of submerged macrophytes for oxic methane production in aquatic ecosystems

scientific article published on 10 May 2022

Probing the diversity of chloromethane-degrading bacteria by comparative genomics and isotopic fractionation

scientific article

Release of methane from aerobic soil: an indication of a novel chemical natural process?

scientific article published on 21 December 2011

Simultaneous Abiotic Production of Greenhouse Gases (CO2, CH4, and N2O) in Subtropical Soils

scientific article published in 2019

Site-specific climatic signals in stable isotope records from Swedish pine forests

Stable Carbon Isotope Signature of Methane Released From Phytoplankton

scientific article published in 2023

Stable carbon isotopes of methane for real-time process monitoring in anaerobic digesters

Stable hydrogen and carbon isotope ratios of methoxyl groups during plant litter degradation

scientific article published on 23 February 2015

Stable hydrogen isotope ratios of lignin methoxyl groups as a paleoclimate proxy and constraint of the geographical origin of wood

scientific article published on 28 August 2007

Stable hydrogen isotope values of lignin methoxyl groups of four tree species across Germany and their implication for temperature reconstruction

scientific article published on 23 November 2016

Stable isotope and high precision concentration measurements confirm that all humans produce and exhale methane

scientific article published on 29 January 2016

Stable isotope determination of ester and ether methyl moieties in plant methoxyl groups ⬇️

scientific article published on October 17, 2011

Subaqueous speleothems (Hells Bells) formed by the interplay of pelagic redoxcline biogeochemistry and specific hydraulic conditions in the El Zapote sinkhole, Yucatán Peninsula, Mexico

scientific article published in 2019

The stable carbon isotope signature of methane produced by saprotrophic fungi

scientific article published in 2020

Tracing the geographical origin of early potato tubers using stable hydrogen isotope ratios of methoxyl groups

scientific article published on 01 December 2008

Transitory microbial habitat in the hyperarid Atacama Desert.

scientific article published on 26 February 2018

Tree-ring lignin proxies in Larix gmelinii forest growing in a permafrost area of northeastern China: Temporal variation and potential for climate reconstructions

scientific article published in 2020

Warm season precipitation signal in δ2 H values of wood lignin methoxyl groups from high elevation larch trees in Switzerland.

scientific article published on 11 July 2017

δ²H, δ¹³C and δ¹⁸O from whole wood, α-cellulose and lignin methoxyl groups in Pinus sylvestris: a multi-parameter approach

scientific article published on 8 July 2015

List of works by Frank Keppler

A stable isotope approach to assessing water loss in fruits and vegetables during storage.

Abiotic methanogenesis from organosulphur compounds under ambient conditions

Abiotic methyl bromide formation from vegetation, and its strong dependence on temperature

Age dependent breath methane in the German population

Aquatic and terrestrial cyanobacteria produce methane

Canadian Arctic Neogene Temperatures Reconstructed From Hydrogen Isotopes of Lignin‐Methoxy Groups From Sub‐Fossil Wood

Carbon, hydrogen and oxygen stable isotope ratios of whole wood, cellulose and lignin methoxyl groups ofPicea abiesas climate proxies

Chloride methylation by plant pectin: an efficient environmentally significant process.

Chlorine Isotope Fractionation of the Major Chloromethane Degradation Processes in the Environment

Chloromethane Degradation in Soils: A Combined Microbial and Two-Dimensional Stable Isotope Approach

Chloromethane emissions in human breath.

Chloromethane formation and degradation in the fern phyllosphere

Chloromethane release from carbonaceous meteorite affords new insight into Mars lander findings.

Climate signals in stable carbon and hydrogen isotopes of lignin methoxy groups from southern German beech trees

Comment on Authenticity and traceability of vanilla flavors by analysis of stable isotopes of carbon and hydrogen

De novo formation of chloroethyne in soil.

Design and application of a synthetic DNA standard for real-time PCR analysis of microbial communities in a biogas digester.

Differentiation of the halogen content of peat samples using ion chromatography after combustion (TX/TOX-IC).

Effects of Temperature and Light on Methane Production of Widespread Marine Phytoplankton

Enhanced formation of methane in plant cell cultures by inhibition of cytochrome c oxidase.

Evidence for a major missing source in the global chloromethane budget from stable carbon isotopes

Evidence for methane production by saprotrophic fungi.

Evidence for methane production by the marine algae &amp;lt;i&amp;gt;Emiliania huxleyi&amp;lt;/i&amp;gt;

Evidence of anaerobic syntrophic acetate oxidation in biogas batch reactors by analysis of 13C carbon isotopes.

Exogenous addition of H2 for an in situ biogas upgrading through biological reduction of carbon dioxide into methane.

Fluxes of trichloroacetic acid between atmosphere, biota, soil, and groundwater ⬇️

Formation of chloroacetic acids from soil, humic acid and phenolic moieties ⬇️

Formation of volatile iodinated alkanes in soil: results from laboratory studies.

Halocarbons produced by natural oxidation processes during degradation of organic matter.

Halogen retention, organohalogens, and the role of organic matter decomposition on halogen enrichment in two Chilean peat bogs.

High Spatiotemporal Dynamics of Methane Production and Emission in Oxic Surface Water

Hydrogen and carbon isotope fractionation during degradation of chloromethane by methylotrophic bacteria

Identification of methanogenic pathways in anaerobic digesters using stable carbon isotopes

Isotopic composition of H2from wood burning: Dependency on combustion efficiency, moisture content, andδD of local precipitation

Late permian changes in conditions of the atmosphere and environments caused by halogenated gases

Long-term monitoring of breath methane

Mean annual temperatures of mid-latitude regions derived from δ(2)H values of wood lignin methoxyl groups and its implications for paleoclimate studies.

Measurements of 13C/12C methane from anaerobic digesters: comparison of optical spectrometry with continuous-flow isotope ratio mass spectrometry

Methane emissions from terrestrial plants under aerobic conditions.

Methane formation in aerobic environments

Methane oxidation in industrial biogas plants - insights in a novel methanotrophic environment evidenced by pmoA gene analyses and stable isotope labelling studies.

Methane production by three widespread marine phytoplankton species: release rates, precursor compounds, and potential relevance for the environment

Methoxyl groups of plant pectin as a precursor of atmospheric methane: evidence from deuterium labelling studies.

Methyl chloride emissions from halophyte leaf litter: Dependence on temperature and chloride content

Methyl sulfates as methoxy isotopic reference materials for δ13 C and δ2 H measurements

Nitrous oxide and methane emissions from cryptogamic covers.

Nitrous oxide effluxes from plants as a potentially important source to the atmosphere

Non-microbial methane formation in oxic soils

Nonheme Iron-Oxo-Catalyzed Methane Formation from Methyl Thioethers: Scope, Mechanism, and Relevance for Natural Systems

Online monitoring of stable carbon isotopes of methane in anaerobic digestion as a new tool for early warning of process instability.

Organic compounds in fluid inclusions of Archean quartz-Analogues of prebiotic chemistry on early Earth.

Peatlands: a major sink of naturally formed organic chlorine

Position-specific isotope analysis of the methyl group carbon in methylcobalamin for the investigation of biomethylation processes

Potential role of submerged macrophytes for oxic methane production in aquatic ecosystems

Probing the diversity of chloromethane-degrading bacteria by comparative genomics and isotopic fractionation

Release of methane from aerobic soil: an indication of a novel chemical natural process?

Simultaneous Abiotic Production of Greenhouse Gases (CO<sub>2</sub>, CH<sub>4</sub>, and N<sub>2</sub>O) in Subtropical Soils

Site-specific climatic signals in stable isotope records from Swedish pine forests

Stable Carbon Isotope Signature of Methane Released From Phytoplankton

Stable carbon isotopes of methane for real-time process monitoring in anaerobic digesters

Stable hydrogen and carbon isotope ratios of methoxyl groups during plant litter degradation

Stable hydrogen isotope ratios of lignin methoxyl groups as a paleoclimate proxy and constraint of the geographical origin of wood

Stable hydrogen isotope values of lignin methoxyl groups of four tree species across Germany and their implication for temperature reconstruction

Stable isotope and high precision concentration measurements confirm that all humans produce and exhale methane

Stable isotope determination of ester and ether methyl moieties in plant methoxyl groups ⬇️

Subaqueous speleothems (Hells Bells) formed by the interplay of pelagic redoxcline biogeochemistry and specific hydraulic conditions in the El Zapote sinkhole, Yucatán Peninsula, Mexico

The stable carbon isotope signature of methane produced by saprotrophic fungi

Tracing the geographical origin of early potato tubers using stable hydrogen isotope ratios of methoxyl groups

Transitory microbial habitat in the hyperarid Atacama Desert.

Tree-ring lignin proxies in Larix gmelinii forest growing in a permafrost area of northeastern China: Temporal variation and potential for climate reconstructions

Warm season precipitation signal in δ2 H values of wood lignin methoxyl groups from high elevation larch trees in Switzerland.

δ²H, δ¹³C and δ¹⁸O from whole wood, α-cellulose and lignin methoxyl groups in Pinus sylvestris: a multi-parameter approach

Evidence for methane production by the marine algae <i>Emiliania huxleyi</i>