This page has only limited features, please log in for full access.

Unclaimed
Asmus Meyer-Plath
Bundesanstalt für Arbeitsschutz und Arbeitsmedizin (BAuA), Nöldnerstr. 40-42, 10317 Berlin, Germany

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 20 November 2020 in Atmosphere
Reads 0
Downloads 0

Despite compelling reports on asbestos-like pathogenicity, regulatory bodies have been hesitant to implement fiber number-based exposure limits for biodurable nanoscale fibers. One reason has been the lack of a practicable strategy for assessing airborne fiber number concentrations. Here, a method is proposed, detailed and tested for compliance checking concentrations of airborne nano- and microscale fibers. It relies on Poisson statistical significance testing of the observed versus a predicted number of fibers on filters that have sampled a known volume of aerosol. The prediction is based on the exposure concentration to test. Analogous to the established counting rules for WHO-fibers, which use a phase contrast microscopy-related visibility criterion of , the new method also introduces a cut-off diameter, now at , which is motivated by toxicological findings on multi-walled carbon nanotubes. This cut-off already reduces the workload by a factor of compared to that necessary for imaging, detecting and counting nanofibers down to in diameter. Together with waiving any attempt to absolutely quantify fiber concentrations, a compliance check at the limit-of-detection results in an analytical workload that renders our new approach practicable. The proposed method was applied to compliance checking in 14 very different workplaces that handled or machined nanofiber-containing materials. It achieved detecting violations of the German benchmark exposure level of nanofibers per cubic meter.

ACS Style

Asmus Meyer-Plath; Daphne Bäger; Nico Dziurowitz; Doris Perseke; Barbara Simonow; Carmen Thim; Daniela Wenzlaff; Sabine Plitzko. A Practicable Measurement Strategy for Compliance Checking Number Concentrations of Airborne Nano- and Microscale Fibers. Atmosphere 2020, 11, 1254 .

AMA Style

Asmus Meyer-Plath, Daphne Bäger, Nico Dziurowitz, Doris Perseke, Barbara Simonow, Carmen Thim, Daniela Wenzlaff, Sabine Plitzko. A Practicable Measurement Strategy for Compliance Checking Number Concentrations of Airborne Nano- and Microscale Fibers. Atmosphere. 2020; 11 (11):1254.

Chicago/Turabian Style

Asmus Meyer-Plath; Daphne Bäger; Nico Dziurowitz; Doris Perseke; Barbara Simonow; Carmen Thim; Daniela Wenzlaff; Sabine Plitzko. 2020. "A Practicable Measurement Strategy for Compliance Checking Number Concentrations of Airborne Nano- and Microscale Fibers." Atmosphere 11, no. 11: 1254.

Journal article
Published: 12 May 2020 in Fibers
Reads 0
Downloads 0

In this work the flexural rigidity of individual large diameter multi-walled carbon nanotubes (MWCNTs) was investigated. The bending modulus were obtained by detecting the resonance frequencies of mechanically excited cantilevered carbon nanotubes using the so-called dynamic scanning electron microscopy technique, and applying the Euler–Bernoulli beam theory. For the nanotubes studied, we determined a modulus of up to 160 GPa. This agrees with values reported by other authors for MWCNTs produced by catalytic chemical vapor deposition, however, it is 6-8 times smaller than values reported for single and multi-walled carbon nanotubes produced by arc-discharge synthesis. Toxicological studies with carbon nanotubes have been showing that inhaled airborne nanofibers that reach the deep airways of the respiratory system may lead to serious, asbestos-like lung diseases. These studies suggested that their toxicity critically depends on the fiber flexural rigidity, with high rigidity causing cell lesions. To complement the correlation between observed toxicological effects and fiber rigidities, reliable and routinely applicable measurement techniques for the flexural rigidity of nanofibers are required.

ACS Style

Renata Fortini; Asmus Meyer-Plath; Dominic Kehren; Ulrich Gernert; Leonardo Agudo Jácome; Heinz Sturm. Measurement of Flexural Rigidity of Multi-Walled Carbon Nanotubes by Dynamic Scanning Electron Microscopy. Fibers 2020, 8, 31 .

AMA Style

Renata Fortini, Asmus Meyer-Plath, Dominic Kehren, Ulrich Gernert, Leonardo Agudo Jácome, Heinz Sturm. Measurement of Flexural Rigidity of Multi-Walled Carbon Nanotubes by Dynamic Scanning Electron Microscopy. Fibers. 2020; 8 (5):31.

Chicago/Turabian Style

Renata Fortini; Asmus Meyer-Plath; Dominic Kehren; Ulrich Gernert; Leonardo Agudo Jácome; Heinz Sturm. 2020. "Measurement of Flexural Rigidity of Multi-Walled Carbon Nanotubes by Dynamic Scanning Electron Microscopy." Fibers 8, no. 5: 31.

Original article
Published: 17 June 2019 in Indoor Air
Reads 0
Downloads 0

A particle exposure experiment inside a large climate‐controlled chamber was conducted. Data on spatial and temporal distribution of nanoscale and fine aerosols in the range of mobility diameters 8 – 600 nm were collected with high resolution, for sodium chloride, fluorescein sodium and silica particles. Exposure scenarios studied, included constant and intermittent source emissions, different aggregation conditions, high (10 h−1) and low (3.5 h−1) air exchange rates (AERs) corresponding to chamber Reynolds number respectively equal to 1.105 and 3.104. Results are presented and analysed to highlight the main determinants of exposure and to determine if the assumptions underlying two‐box models hold under various scenarios. The main determinants of exposure found were the source generation rate and the ventilation rate. The effect of particles nature was indiscernible and the decrease of airborne total number concentrations attributable to surface deposition was estimated lower than 2% when the source was active. A near‐field/far‐field structure of aerosol concentration was always observed for the AER=10 h−1 but for AER=3.5 h−1 a single field structure was found. The particle size distribution was always homogeneous in space but a general shift of particles diameter (‐8% to +16%) was observed between scenarios in correlation with the AER and with the source position, presumably largely attributable to aggregation. This article is protected by copyright. All rights reserved.

ACS Style

Emmanuel Belut; Araceli Sánchez Jiménez; Asmus Meyer‐Plath; Antti Joonas Koivisto; Ismo K. Koponen; Alexander C. Ø. Jensen; Laura MacCalman; Ilse Tuinman; Wouter Fransman; Maidá Domat; Mariya Bivolarova; Martie van Tongeren. Indoor dispersion of airborne nano and fine particles: Main factors affecting spatial and temporal distribution in the frame of exposure modeling. Indoor Air 2019, 29, 803 -816.

AMA Style

Emmanuel Belut, Araceli Sánchez Jiménez, Asmus Meyer‐Plath, Antti Joonas Koivisto, Ismo K. Koponen, Alexander C. Ø. Jensen, Laura MacCalman, Ilse Tuinman, Wouter Fransman, Maidá Domat, Mariya Bivolarova, Martie van Tongeren. Indoor dispersion of airborne nano and fine particles: Main factors affecting spatial and temporal distribution in the frame of exposure modeling. Indoor Air. 2019; 29 (5):803-816.

Chicago/Turabian Style

Emmanuel Belut; Araceli Sánchez Jiménez; Asmus Meyer‐Plath; Antti Joonas Koivisto; Ismo K. Koponen; Alexander C. Ø. Jensen; Laura MacCalman; Ilse Tuinman; Wouter Fransman; Maidá Domat; Mariya Bivolarova; Martie van Tongeren. 2019. "Indoor dispersion of airborne nano and fine particles: Main factors affecting spatial and temporal distribution in the frame of exposure modeling." Indoor Air 29, no. 5: 803-816.

Journal article
Published: 11 October 2018 in Powder Technology
Reads 0
Downloads 0

Dustiness testing probes for the propensity of a powdery material to release dust particles following agitation. For high aspect-ratio materials like nanotubes, the most important dust fraction is that of potentially carcinogenic fibres (WHO-fibres). We developed the fluidizer particularly for fibres that makes use of vibro-fluidization in order to effectively disentangle single fibres and agglomerates of multi-walled carbon nanotube powders. Counting rules for morphological characterization of collected particles by means of electron microscopy were established, allowing quantifying the WHO-fibre fraction. Dustiness tests on 15 different multi-walled carbon nanotubes were performed using two different levels of energy input for each material. The fluidizer accomplished bubbling fluidization for 13 out of the 15 multi-walled carbon nanotubes, resulting in continuous aerosol generation with stable particle number concentration and a high fraction of single fibres. Dustiness measurands like average particle number concentrations varied by three orders of magnitude. Morphological characterization of particles on aerosol samples proved to be essential to overcome the limitations of the applied aerosol instruments in quantifying the WHO-fibre fraction, therefore allowing material ranking based on associated risk. The materials showed strong ordering discrepancy when ranked based on total dustiness and WHO-fibre dustiness. Several multi-walled carbon nanotubes showed WHO-fibre concentrations high enough to potentially cause workplace exposure at hazardous concentration levels in case powders are handled carelessly.

ACS Style

Dirk Broßell; Elisabeth Heunisch; Asmus Meyer-Plath; Daphne Bäger; Volker Bachmann; Kerstin Kämpf; Nico Dziurowitz; Carmen Thim; Daniela Wenzlaff; John Schumann; Sabine Plitzko. Assessment of nanofibre dustiness by means of vibro-fluidization. Powder Technology 2018, 342, 491 -508.

AMA Style

Dirk Broßell, Elisabeth Heunisch, Asmus Meyer-Plath, Daphne Bäger, Volker Bachmann, Kerstin Kämpf, Nico Dziurowitz, Carmen Thim, Daniela Wenzlaff, John Schumann, Sabine Plitzko. Assessment of nanofibre dustiness by means of vibro-fluidization. Powder Technology. 2018; 342 ():491-508.

Chicago/Turabian Style

Dirk Broßell; Elisabeth Heunisch; Asmus Meyer-Plath; Daphne Bäger; Volker Bachmann; Kerstin Kämpf; Nico Dziurowitz; Carmen Thim; Daniela Wenzlaff; John Schumann; Sabine Plitzko. 2018. "Assessment of nanofibre dustiness by means of vibro-fluidization." Powder Technology 342, no. : 491-508.

Research paper
Published: 02 June 2018 in Journal of Nanoparticle Research
Reads 0
Downloads 0

The assessment of the toxicity of airborne nanofibers is an important task. It relies on toxicological inhalation studies and validated exposure measurement techniques. Both require nanofiber-containing aerosols of known morphological composition and controlled fraction of individual fibers. Here, a dry powder dispersion method is presented that operates with mixtures of nanofibers and microscale beads. Aerosolization experiments of mixtures of multi-walled carbon nanotubes (MWCNTs) and glass beads that were continuously fed into a Venturi nozzle enabled high generation rates of aerosols composed of individual and agglomerate nanofiber structures. The aerosol process achieved good stability over more than 2 h with respect to concentration and aerodynamic size distribution. Its operation duration is limited only by the reservoir volume of the cyclone used to separate the beads from the aerosol. The aerosol concentration can be controlled by changing the mass ratio of MWCNTs and glass beads or by adapting the mass feed rate to the nozzle. For two agglomerated MWCNT materials, aerosol concentrations ranged from 1700 to 64,000 nano-objects per cm3. Comprehensive scanning electron microscope analysis of filter samples was performed to categorize and determine the morphological composition of the aerosol, its fiber content as well as fiber length and diameter distributions. High fractions of individual fibers of up to 34% were obtained, which shows the setup to be capable of dispersing also highly tangled MWCNT agglomerates effectively.

ACS Style

Barbara Katrin Simonow; Daniela Wenzlaff; Asmus Meyer-Plath; Nico Dziurowitz; Carmen Thim; Jana Thiel; Mikolaj Jandy; Sabine Plitzko. Continuous dry dispersion of multi-walled carbon nanotubes to aerosols with high concentrations of individual fibers. Journal of Nanoparticle Research 2018, 20, 1 -17.

AMA Style

Barbara Katrin Simonow, Daniela Wenzlaff, Asmus Meyer-Plath, Nico Dziurowitz, Carmen Thim, Jana Thiel, Mikolaj Jandy, Sabine Plitzko. Continuous dry dispersion of multi-walled carbon nanotubes to aerosols with high concentrations of individual fibers. Journal of Nanoparticle Research. 2018; 20 (6):1-17.

Chicago/Turabian Style

Barbara Katrin Simonow; Daniela Wenzlaff; Asmus Meyer-Plath; Nico Dziurowitz; Carmen Thim; Jana Thiel; Mikolaj Jandy; Sabine Plitzko. 2018. "Continuous dry dispersion of multi-walled carbon nanotubes to aerosols with high concentrations of individual fibers." Journal of Nanoparticle Research 20, no. 6: 1-17.

Journal article
Published: 24 April 2018 in Environments
Reads 0
Downloads 0

Models are increasingly used to estimate and pre-emptively calculate the occupational exposure of airborne released particulate matter. Typical two-box models assume instant and fully mixed air volumes, which can potentially cause issues in cases with fast processes, slow air mixing, and/or large volumes. In this study, we present an aerosol dispersion model and validate it by comparing the modelled concentrations with concentrations measured during chamber experiments. We investigated whether a better estimation of concentrations was possible by using different geometrical layouts rather than a typical two-box layout. A one-box, two-box, and two three-box layouts were used. The one box model was found to underestimate the concentrations close to the source, while overestimating the concentrations in the far field. The two-box model layout performed well based on comparisons from the chamber study in systems with a steady source concentration for both slow and fast mixing. The three-box layout was found to better estimate the concentrations and the timing of the peaks for fluctuating concentrations than the one-box or two-box layouts under relatively slow mixing conditions. This finding suggests that industry-relevant scaled volumes should be tested in practice to gain more knowledge about when to use the two-box or the three-box layout schemes for multi-box models.

ACS Style

Alexander C. Ø. Jensen; Miikka Dal Maso; Antti J. Koivisto; Emmanuel Belut; Asmus Meyer-Plath; Martie Van Tongeren; Araceli Sánchez Jiménez; Ilse Tuinman; Maida Domat; Jørn Toftum; Ismo K. Koponen. Comparison of Geometrical Layouts for a Multi-Box Aerosol Model from a Single-Chamber Dispersion Study. Environments 2018, 5, 52 .

AMA Style

Alexander C. Ø. Jensen, Miikka Dal Maso, Antti J. Koivisto, Emmanuel Belut, Asmus Meyer-Plath, Martie Van Tongeren, Araceli Sánchez Jiménez, Ilse Tuinman, Maida Domat, Jørn Toftum, Ismo K. Koponen. Comparison of Geometrical Layouts for a Multi-Box Aerosol Model from a Single-Chamber Dispersion Study. Environments. 2018; 5 (5):52.

Chicago/Turabian Style

Alexander C. Ø. Jensen; Miikka Dal Maso; Antti J. Koivisto; Emmanuel Belut; Asmus Meyer-Plath; Martie Van Tongeren; Araceli Sánchez Jiménez; Ilse Tuinman; Maida Domat; Jørn Toftum; Ismo K. Koponen. 2018. "Comparison of Geometrical Layouts for a Multi-Box Aerosol Model from a Single-Chamber Dispersion Study." Environments 5, no. 5: 52.

Comparative study
Published: 01 December 2017 in Science of The Total Environment
Reads 0
Downloads 0

Personal monitors based on unipolar diffusion charging (miniDiSC/DiSCmini, NanoTracer, Partector) can be used to assess the individual exposure to nanoparticles in different environments. The charge acquired by the aerosol particles is nearly proportional to the particle diameter and, by coincidence, also nearly proportional to the alveolar lung-deposited surface area (LDSA), the metric reported by all three instruments. In addition, the miniDiSC/DiSCmini and the NanoTracer report particle number concentration and mean particle size. In view of their use for personal exposure studies, the comparability of these personal monitors was assessed in two measurement campaigns. Altogether 29 different polydisperse test aerosols were generated during the two campaigns, covering a large range of particle sizes, morphologies and concentrations. The data provided by the personal monitors were compared with those obtained from reference instruments: a scanning mobility particle sizer (SMPS) for LDSA and mean particle size and a ultrafine particle counter (UCPC) for number concentration. The results indicated that the LDSA concentrations and the mean particle sizes provided by all investigated instruments in this study were in the order of ±30% of the reference value obtained from the SMPS when the particle sizes of the test aerosols generated were within 20-400nm and the instruments were properly calibrated. Particle size, morphology and concentration did not have a major effect within the aforementioned limits. The comparability of the number concentrations was found to be slightly worse and in the range of ±50% of the reference value obtained from the UCPC. In addition, a minor effect of the particle morphology on the number concentration measurements was observed. The presence of particles >400nm can drastically bias the measurement results of all instruments and all metrics determined.

ACS Style

Ana Maria Todea; Stefanie Beckmann; Heinz Kaminski; Delphine Bard; Sébastien Bau; Simon Clavaguera; Dirk Dahmann; Hélène Dozol; Nico Dziurowitz; Karine Elihn; Martin Fierz; Göran Lidén; Asmus Meyer-Plath; Christian Monz; Volker Neumann; Johannes Pelzer; Barbara Katrin Simonow; Patrick Thali; Ilse Tuinman; Arjan van der Vleuten; Huub Vroomen; Christof Asbach. Inter-comparison of personal monitors for nanoparticles exposure at workplaces and in the environment. Science of The Total Environment 2017, 605-606, 929 -945.

AMA Style

Ana Maria Todea, Stefanie Beckmann, Heinz Kaminski, Delphine Bard, Sébastien Bau, Simon Clavaguera, Dirk Dahmann, Hélène Dozol, Nico Dziurowitz, Karine Elihn, Martin Fierz, Göran Lidén, Asmus Meyer-Plath, Christian Monz, Volker Neumann, Johannes Pelzer, Barbara Katrin Simonow, Patrick Thali, Ilse Tuinman, Arjan van der Vleuten, Huub Vroomen, Christof Asbach. Inter-comparison of personal monitors for nanoparticles exposure at workplaces and in the environment. Science of The Total Environment. 2017; 605-606 ():929-945.

Chicago/Turabian Style

Ana Maria Todea; Stefanie Beckmann; Heinz Kaminski; Delphine Bard; Sébastien Bau; Simon Clavaguera; Dirk Dahmann; Hélène Dozol; Nico Dziurowitz; Karine Elihn; Martin Fierz; Göran Lidén; Asmus Meyer-Plath; Christian Monz; Volker Neumann; Johannes Pelzer; Barbara Katrin Simonow; Patrick Thali; Ilse Tuinman; Arjan van der Vleuten; Huub Vroomen; Christof Asbach. 2017. "Inter-comparison of personal monitors for nanoparticles exposure at workplaces and in the environment." Science of The Total Environment 605-606, no. : 929-945.

Review
Published: 01 December 2017 in Science of The Total Environment
Reads 0
Downloads 0

Exposure to airborne agents needs to be assessed in the personal breathing zone by the use of personal measurement equipment. Specific measurement devices for assessing personal exposure to airborne nanomaterials have only become available in the recent years. They can be differentiated into direct-reading personal monitors and personal samplers that collect the airborne nanomaterials for subsequent analyses. This article presents a review of the available personal monitors and samplers and summarizes the available literature regarding their accuracy, comparability and field applicability. Due to the novelty of the instruments, the number of published studies is still relatively low. Where applicable, literature data is therefore complemented with published and unpublished results from the recently finished nanoIndEx project. The presented data show that the samplers and monitors are robust and ready for field use with sufficient accuracy and comparability. However, several limitations apply, e.g. regarding the particle size range of the personal monitors and their in general lower accuracy and comparability compared with their stationary counterparts. The decision whether a personal monitor or a personal sampler shall be preferred depends strongly on the question to tackle. In many cases, a combination of a personal monitor and a personal sampler may be the best choice to obtain conclusive results.

ACS Style

Christof Asbach; Carla Alexander; Simon Clavaguera; Dirk Dahmann; Hélène Dozol; Bertrand Faure; Martin Fierz; Luca Fontana; Ivo Iavicoli; Heinz Kaminski; Laura MacCalman; Asmus Meyer-Plath; Barbara Simonow; Martie van Tongeren; Ana Maria Todea. Review of measurement techniques and methods for assessing personal exposure to airborne nanomaterials in workplaces. Science of The Total Environment 2017, 603-604, 793 -806.

AMA Style

Christof Asbach, Carla Alexander, Simon Clavaguera, Dirk Dahmann, Hélène Dozol, Bertrand Faure, Martin Fierz, Luca Fontana, Ivo Iavicoli, Heinz Kaminski, Laura MacCalman, Asmus Meyer-Plath, Barbara Simonow, Martie van Tongeren, Ana Maria Todea. Review of measurement techniques and methods for assessing personal exposure to airborne nanomaterials in workplaces. Science of The Total Environment. 2017; 603-604 ():793-806.

Chicago/Turabian Style

Christof Asbach; Carla Alexander; Simon Clavaguera; Dirk Dahmann; Hélène Dozol; Bertrand Faure; Martin Fierz; Luca Fontana; Ivo Iavicoli; Heinz Kaminski; Laura MacCalman; Asmus Meyer-Plath; Barbara Simonow; Martie van Tongeren; Ana Maria Todea. 2017. "Review of measurement techniques and methods for assessing personal exposure to airborne nanomaterials in workplaces." Science of The Total Environment 603-604, no. : 793-806.

Journal article
Published: 15 March 2013 in Applied Catalysis A: General
Reads 0
Downloads 0

Brominated single-walled carbon nanotubes [(Br)n-SWCNT) produced by the plasma-chemical technique were involved in the liquid-phase process of hydrocarbons aerobic oxidation. The significant catalytic effect of the (Br)n-SWCNT was revealed at first by the cumene initiated model oxidation and then in experiments on profound aerobic oxidation of petroleum naphthenic fraction derived from the commercial Azerbaijan (Baku) oils blend diesel cut. The ability of (Br)n-SWCNT to accelerate the aerobic oxidation of the hydrocarbons was found out for the first time. Obviously this phenomenon originates from the peculiarities of electronic configuration of the (Br)n-CNT patterns. The plausible mechanism of (Br)n-SWCNT catalytic action is inclined to the formation of reactive oxygen species. The catalytic activity of (Br)n-SWCNT markedly exceeds the activity of the industrial catalysts, manganese salt of indigenous petroleum acids, used for the liquid phase petroleum hydrocarbons oxidation process.

ACS Style

Eldar Zeynalov; Joerg Friedrich; Asmus Andres Meyer-Plath; Gundula Hidde; Lyatif Nuriyev; Aygun Aliyeva; Yutta Cherepnova. Plasma-chemically brominated single-walled carbon nanotubes as novel catalysts for oil hydrocarbons aerobic oxidation. Applied Catalysis A: General 2013, 454, 115 -118.

AMA Style

Eldar Zeynalov, Joerg Friedrich, Asmus Andres Meyer-Plath, Gundula Hidde, Lyatif Nuriyev, Aygun Aliyeva, Yutta Cherepnova. Plasma-chemically brominated single-walled carbon nanotubes as novel catalysts for oil hydrocarbons aerobic oxidation. Applied Catalysis A: General. 2013; 454 ():115-118.

Chicago/Turabian Style

Eldar Zeynalov; Joerg Friedrich; Asmus Andres Meyer-Plath; Gundula Hidde; Lyatif Nuriyev; Aygun Aliyeva; Yutta Cherepnova. 2013. "Plasma-chemically brominated single-walled carbon nanotubes as novel catalysts for oil hydrocarbons aerobic oxidation." Applied Catalysis A: General 454, no. : 115-118.

Journal article
Published: 05 September 2012 in International Journal of Applied Electromagnetics and Mechanics
Reads 0
Downloads 0
ACS Style

Andrea Harrer; Maxim Daschewski; Jens Prager; Marc Kreutzbruck; Matthias Guderian; Asmus Meyer-Plath. Thermoacoustic generation of airborne ultrasound using carbon materials at the micro- and nanoscale. International Journal of Applied Electromagnetics and Mechanics 2012, 39, 35 -41.

AMA Style

Andrea Harrer, Maxim Daschewski, Jens Prager, Marc Kreutzbruck, Matthias Guderian, Asmus Meyer-Plath. Thermoacoustic generation of airborne ultrasound using carbon materials at the micro- and nanoscale. International Journal of Applied Electromagnetics and Mechanics. 2012; 39 (1-4):35-41.

Chicago/Turabian Style

Andrea Harrer; Maxim Daschewski; Jens Prager; Marc Kreutzbruck; Matthias Guderian; Asmus Meyer-Plath. 2012. "Thermoacoustic generation of airborne ultrasound using carbon materials at the micro- and nanoscale." International Journal of Applied Electromagnetics and Mechanics 39, no. 1-4: 35-41.

Journal article
Published: 01 August 2012 in Carbon
Reads 0
Downloads 0
ACS Style

Asmus Andres Meyer-Plath; Guillermo Orts-Gil; Sergey Petrov; Franz Oleszak; Heinz-Eberhard Maneck; Ilona Dörfel; Oskar Haase; Silke Richter; Reinhard Mach. Plasma-thermal purification and annealing of carbon nanotubes. Carbon 2012, 50, 3934 -3942.

AMA Style

Asmus Andres Meyer-Plath, Guillermo Orts-Gil, Sergey Petrov, Franz Oleszak, Heinz-Eberhard Maneck, Ilona Dörfel, Oskar Haase, Silke Richter, Reinhard Mach. Plasma-thermal purification and annealing of carbon nanotubes. Carbon. 2012; 50 (10):3934-3942.

Chicago/Turabian Style

Asmus Andres Meyer-Plath; Guillermo Orts-Gil; Sergey Petrov; Franz Oleszak; Heinz-Eberhard Maneck; Ilona Dörfel; Oskar Haase; Silke Richter; Reinhard Mach. 2012. "Plasma-thermal purification and annealing of carbon nanotubes." Carbon 50, no. 10: 3934-3942.

Journal article
Published: 31 March 2012 in Carbon
Reads 0
Downloads 0

Chemical functionalization of carbon nanotubes (CNT) with nucleophiles requires introduction of electrophilic reactive sites on the CNTs. This can, for instance, be accomplished by the chemical bromination procedure with elemental bromine and a set of Lewis acids (BBr3, BF3 × Et2O, AlBr3, FeBr3, ZnBr2, TiBr4, SiBr4, SnBr4, VBr3) or a radical starter like dibenzoylperoxide (DBPO) in appropriate solvents at varied temperature. The present approach to electrophilic sites relies on the well-known electrophilic aromatic substitution or addition of bromine with aromatic structural units. In addition to the use of bromine, the introduction of haloalkyl groups was also investigated here using bis-electrophiles or haloalcohols and Brønsted acids. The advantages and drawbacks of the studied reaction conditions, the obtained degree of bromination as analyzed by X-ray photoelectron spectroscopy (XPS) and the amount of introduced bromine that can be substituted by a nucleophile are presented and discussed.

ACS Style

Sven Hanelt; Jörg F. Friedrich; Guillermo Orts-Gil; Asmus Meyer-Plath. Study of Lewis acid catalyzed chemical bromination and bromoalkylation of multi-walled carbon nanotubes. Carbon 2012, 1 .

AMA Style

Sven Hanelt, Jörg F. Friedrich, Guillermo Orts-Gil, Asmus Meyer-Plath. Study of Lewis acid catalyzed chemical bromination and bromoalkylation of multi-walled carbon nanotubes. Carbon. 2012; ():1.

Chicago/Turabian Style

Sven Hanelt; Jörg F. Friedrich; Guillermo Orts-Gil; Asmus Meyer-Plath. 2012. "Study of Lewis acid catalyzed chemical bromination and bromoalkylation of multi-walled carbon nanotubes." Carbon , no. : 1.

Plasmatechnologie
Published: 13 February 2012 in Vakuum in Forschung und Praxis
Reads 0
Downloads 0

Die hochselektive und ausbeutereiche plasmachemische Bromierung von Polyolefinoberflächen wurde auf graphitische Materialien übertragen. Oberflächen von graphenartigem Highly Oriented Pyrolytic Graphite (HOPG), natürlichem Graphit, mehrwandige Kohlenstoffnanoröhren (MWCNT) sowie Kohlenstoff‐Fasern wurden im Bromdampfplasma behandelt. Während die Bromierung von Polyolefinoberflächen als radikalische Wasserstoffabstraktion mit nachfolgender Addition (Rekombination) oder durch nucleophile Substitution an sp3‐hybridisierten C‐Atomen abläuft, können graphitische Strukturen sowohl an sp3‐hybridisierten Strukturdefekten als auch durch elektrophile Addition an vollständig C‐substituierte aromatische Doppelbindungen bromiert werden. Dabei werden die planaren (graphitischen) sp2‐C‐Atome in die tetraedrische sp3‐Hybridisierung umgewandelt und zu elektrisch nichtleitenden Strukturen gefaltet. Die maximalen Bromausbeuten bei Verwendung von Brom als Plasmamedium lagen je nach Substrat zwischen 10–50% Br/C, mit Bromoform deutlich darüber, was durch Kombinationen von Bromoform mit Brom oder Allylbromid mit Bromoform durch Schichtbildung auf über 70% Br/C gesteigert werden konnte. An die C‐Br‐Gruppen wurden nasschemisch verschiedene Amine nucleophil gepfropft. Die Pfropfausbeuten von 1–10 Moleküle je 100 C lagen deutlich niedriger als die erreichten Pfropfgrade von etwa 1–22 Moleküle je 100 C‐Atome an Polyolefinoberflächen. Da nach der chemischen Pfropfung nahezu alle nichtgepfropften Br‐Gruppen verschwunden waren, muss auf eine bevorzugte Rekonstruktion der planaren sp2‐Graphitschicht geschlossen werden.

ACS Style

Jörg Friedrich; Sascha Wettmarshausen; Asmus Andres Meyer-Plath; Sylvia Ziemann; Gundula Hidde; Eldar Zeynalov. Plasmabromierung von graphitischen Materialien. Vakuum in Forschung und Praxis 2012, 24, 24 -29.

AMA Style

Jörg Friedrich, Sascha Wettmarshausen, Asmus Andres Meyer-Plath, Sylvia Ziemann, Gundula Hidde, Eldar Zeynalov. Plasmabromierung von graphitischen Materialien. Vakuum in Forschung und Praxis. 2012; 24 (1):24-29.

Chicago/Turabian Style

Jörg Friedrich; Sascha Wettmarshausen; Asmus Andres Meyer-Plath; Sylvia Ziemann; Gundula Hidde; Eldar Zeynalov. 2012. "Plasmabromierung von graphitischen Materialien." Vakuum in Forschung und Praxis 24, no. 1: 24-29.

Proceedings article
Published: 01 January 2012 in INTERNATIONAL CONGRESS ON ULTRASONICS: Gdańsk 2011
Reads 0
Downloads 0

A method has been developed for the generation of airborne ultrasound using the thermoacoustic principle applied to carbonmaterials at the micro- and nanoscale. Such materials are shown to be capable to emitting the ultrasound. We tested the acoustic performance of electrospun polyacrylonitrile-derived carbon nanofibers tissues and determined the sound pressure for frequencies up to 350 kHz. The experimental results are compared to analytic calculations.

ACS Style

M. Daschewski; A. Harrer; J. Prager; M. Kreutzbruck; M. Guderian; Asmus Andres Meyer-Plath. Carbon nanomaterials as broadband airborne ultrasound transducer. INTERNATIONAL CONGRESS ON ULTRASONICS: Gdańsk 2011 2012, 1 .

AMA Style

M. Daschewski, A. Harrer, J. Prager, M. Kreutzbruck, M. Guderian, Asmus Andres Meyer-Plath. Carbon nanomaterials as broadband airborne ultrasound transducer. INTERNATIONAL CONGRESS ON ULTRASONICS: Gdańsk 2011. 2012; ():1.

Chicago/Turabian Style

M. Daschewski; A. Harrer; J. Prager; M. Kreutzbruck; M. Guderian; Asmus Andres Meyer-Plath. 2012. "Carbon nanomaterials as broadband airborne ultrasound transducer." INTERNATIONAL CONGRESS ON ULTRASONICS: Gdańsk 2011 , no. : 1.

Journal article
Published: 01 August 2011 in Carbon
Reads 0
Downloads 0
ACS Style

Sven Hanelt; Guillermo Orts-Gil; Jörg F. Friedrich; Asmus Meyer-Plath. Differentiation and quantification of surface acidities on MWCNTs by indirect potentiometric titration. Carbon 2011, 49, 2978 -2988.

AMA Style

Sven Hanelt, Guillermo Orts-Gil, Jörg F. Friedrich, Asmus Meyer-Plath. Differentiation and quantification of surface acidities on MWCNTs by indirect potentiometric titration. Carbon. 2011; 49 (9):2978-2988.

Chicago/Turabian Style

Sven Hanelt; Guillermo Orts-Gil; Jörg F. Friedrich; Asmus Meyer-Plath. 2011. "Differentiation and quantification of surface acidities on MWCNTs by indirect potentiometric titration." Carbon 49, no. 9: 2978-2988.

Conference paper
Published: 06 July 2011 in Journal of Physics: Conference Series
Reads 0
Downloads 0
ACS Style

C Emond; C Rolando; S Hirano; F Schuster; Olivier Jolliet; K Maghni; Asmus Andres Meyer-Plath; S Hallé; L Vandelac; C Sentein; C Torkaski. The International Team in NanosafeTy (TITNT): A Multidisciplinary group for an improvement of Nanorisk Assessment and Management. Journal of Physics: Conference Series 2011, 304, 1 .

AMA Style

C Emond, C Rolando, S Hirano, F Schuster, Olivier Jolliet, K Maghni, Asmus Andres Meyer-Plath, S Hallé, L Vandelac, C Sentein, C Torkaski. The International Team in NanosafeTy (TITNT): A Multidisciplinary group for an improvement of Nanorisk Assessment and Management. Journal of Physics: Conference Series. 2011; 304 ():1.

Chicago/Turabian Style

C Emond; C Rolando; S Hirano; F Schuster; Olivier Jolliet; K Maghni; Asmus Andres Meyer-Plath; S Hallé; L Vandelac; C Sentein; C Torkaski. 2011. "The International Team in NanosafeTy (TITNT): A Multidisciplinary group for an improvement of Nanorisk Assessment and Management." Journal of Physics: Conference Series 304, no. : 1.

Conference paper
Published: 06 July 2011 in Journal of Physics: Conference Series
Reads 0
Downloads 0

Nanotechnologies promise to contribute significantly to major technological challenges of the upcoming century. Despite profound scientific progress in the last decades, only minor advances have been made in the field of nanomaterial toxicology. The International Team in Nanosafety (TITNT) is an international and multidisciplinary group of scientists, which aims at better understanding the risks of nanomaterials. Carbon nanotubes (CNT) account for one of the most promising nanomaterials and have therefore been chosen as representative material for nanoscaled particles. They are currently investigated by the different platforms of TITNT. As a starting point, the present report summarizes a literature-based study on the physico-chemical properties of CNT, as they are closely linked with toxicological properties. A brief introduction to synthesis, purification and material properties is given. Characterization methods for CNT are discussed with respect to their reliability and the information content on chemical properties. Recommendations for a set of standard characterizations mandatory for toxicological assessment are derived.

ACS Style

Florian F Schweinberger; Asmus Andres Meyer-Plath. Status of characterization techniques for carbon nanotubes and suggestions towards standards suitable for toxicological assessment. Journal of Physics: Conference Series 2011, 304, 012087 .

AMA Style

Florian F Schweinberger, Asmus Andres Meyer-Plath. Status of characterization techniques for carbon nanotubes and suggestions towards standards suitable for toxicological assessment. Journal of Physics: Conference Series. 2011; 304 (1):012087.

Chicago/Turabian Style

Florian F Schweinberger; Asmus Andres Meyer-Plath. 2011. "Status of characterization techniques for carbon nanotubes and suggestions towards standards suitable for toxicological assessment." Journal of Physics: Conference Series 304, no. 1: 012087.

Book chapter
Published: 29 November 2010 in Polymer Surface Modification: Relevance to Adhesion, Volume 5
Reads 0
Downloads 0
ACS Style

S. Wettmarshausen; R. Mix; A. Meyer-Plath; H.-U. Mittmann; J. F. Friedrich. Plasma Bromination —A Selective Way To Monotype Functionalized Polymer Surfaces. Polymer Surface Modification: Relevance to Adhesion, Volume 5 2010, 1 -18.

AMA Style

S. Wettmarshausen, R. Mix, A. Meyer-Plath, H.-U. Mittmann, J. F. Friedrich. Plasma Bromination —A Selective Way To Monotype Functionalized Polymer Surfaces. Polymer Surface Modification: Relevance to Adhesion, Volume 5. 2010; ():1-18.

Chicago/Turabian Style

S. Wettmarshausen; R. Mix; A. Meyer-Plath; H.-U. Mittmann; J. F. Friedrich. 2010. "Plasma Bromination —A Selective Way To Monotype Functionalized Polymer Surfaces." Polymer Surface Modification: Relevance to Adhesion, Volume 5 , no. : 1-18.

Journal article
Published: 01 November 2010 in Carbon
Reads 0
Downloads 0
ACS Style

J.F. Friedrich; S. Wettmarshausen; S. Hanelt; R. Mach; R. Mix; E.B. Zeynalov; Asmus Andres Meyer-Plath. Plasma-chemical bromination of graphitic materials and its use for subsequent functionalization and grafting of organic molecules. Carbon 2010, 48, 3884 -3894.

AMA Style

J.F. Friedrich, S. Wettmarshausen, S. Hanelt, R. Mach, R. Mix, E.B. Zeynalov, Asmus Andres Meyer-Plath. Plasma-chemical bromination of graphitic materials and its use for subsequent functionalization and grafting of organic molecules. Carbon. 2010; 48 (13):3884-3894.

Chicago/Turabian Style

J.F. Friedrich; S. Wettmarshausen; S. Hanelt; R. Mach; R. Mix; E.B. Zeynalov; Asmus Andres Meyer-Plath. 2010. "Plasma-chemical bromination of graphitic materials and its use for subsequent functionalization and grafting of organic molecules." Carbon 48, no. 13: 3884-3894.

Journal article
Published: 01 June 2009 in Plasma Processes and Polymers
Reads 0
Downloads 0

Among new types of plasma processes, the underwater plasma is one of the most attractive methods for functionalization of polymer surfaces. The interesting features of plasma solution system are that the material surfaces to be modified remain in contact with the plasma‐moderated solution. The role of plasma‐moderated liquids, allows the reach of the reactive species through solution onto the geometrically hindered sites. The UV radiation produced in plasma formation helps in generating additional excited, ionized, and dissociated molecules and species in the reaction solution. An interesting feature of the technique is its flexibility to use a wide variety of additives as or in solution system. This allows us to create a selective or monotype functionalization of material surfaces. Such system was studied for the selective hydroxyl functionalization of polypropylene surface. The oxidation of polymer surfaces and the introduction of O‐containing functional groups by underwater plasma was found to exceed concentrations typically achieved in oxygen low‐pressure gas discharge plasmas up‐to two‐folds (maximal 56 O/100 C). The fraction of OH groups among all O‐containing moieties amounts from 25 to 40% in comparison to that in the gas plasma of about 10% OH groups. Addition of hydrogen peroxide into this same system increases the fraction of CO bonds up to 75% (27‐OH/100 O). A study was focused to optimize the role of hydrogen peroxide on the efficiency of oxidation and selectivity with chemical derivatization with respect to the formation of mono‐sort hydroxyl functionalities, calculated using a chemical derivatization technique.

ACS Style

Ranjit Joshi; Rolf-Dieter Schulze; Asmus Andres Meyer-Plath; Manfred H. Wagner; Jörg F. Friedrich. Selective Surface Modification of Polypropylene using Underwater Plasma Technique or Underwater Capillary Discharge. Plasma Processes and Polymers 2009, 6, S218 -S222.

AMA Style

Ranjit Joshi, Rolf-Dieter Schulze, Asmus Andres Meyer-Plath, Manfred H. Wagner, Jörg F. Friedrich. Selective Surface Modification of Polypropylene using Underwater Plasma Technique or Underwater Capillary Discharge. Plasma Processes and Polymers. 2009; 6 (S1):S218-S222.

Chicago/Turabian Style

Ranjit Joshi; Rolf-Dieter Schulze; Asmus Andres Meyer-Plath; Manfred H. Wagner; Jörg F. Friedrich. 2009. "Selective Surface Modification of Polypropylene using Underwater Plasma Technique or Underwater Capillary Discharge." Plasma Processes and Polymers 6, no. S1: S218-S222.