Institution
DECHEMA
Nonprofit•Frankfurt am Main, Germany•
About: DECHEMA is a nonprofit organization based out in Frankfurt am Main, Germany. It is known for research contribution in the topics: Corrosion & Oxide. The organization has 756 authors who have published 1307 publications receiving 25693 citations.
Papers published on a yearly basis
Papers
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TL;DR: A new approach for the use of methane as energy source is developed, after thermal methane cracking, only the energy content of the hydrogen is used and the carbon is stored safely and retrievably in disused coal beds.
Abstract: Despite a rising output, in the last few decades the known reserves of fossil energy resources have steadily increased. Additionally, there are in all likelihood tremendous reserves of methane hydrate. In view of the climate change, new means must be explored for its use as an energy source. Starting with an assessment of various options for dealing with the carbon cycle and thermodynamic considerations of methane chemistry, a new approach for the use of methane as energy source is developed in this Concept. After thermal methane cracking, only the energy content of the hydrogen is used and the carbon is stored safely and retrievably in disused coal beds. Arguments for the viability of a carbon moratorium of this kind are discussed.
14 citations
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TL;DR: In this paper, a mathematical model is developed in which the different steps which are required for the formation of metal chlorides and their removal from the surface are described, and it is assumed that the slowest of such formation or transport steps determines the kinetics of high temperature corrosion.
Abstract: Operating atmospheres of many industrial high temperature processes contain a certain amount of halogens, in most cases chlorine. Halogens have the tendency of forming volatile metal chlorides of the general formula MxCly, which are well known to play a critical role in high temperature corrosion processes, when present at a significant amount. Thermodynamic calculations give a valuable hint, whether a reaction product can occur and how volatile such products can potentially be, when the partial pressures are calculated. However, such calculations reflect thermodynamically stable conditions, while in open systems the local kinetics control the process of surface reactions. For each specific condition, the reaction rates and thus the corrosion rates have to be determined. In previous work, we have shown that corrosion kinetics which lead to the formation of volatile products follows different steps. In this work, a mathematical model is developed in which the different steps, which are required for the formation of metal chlorides and their removal from the surface are described. It is assumed that the slowest of such formation or transport steps determines the kinetics of high temperature corrosion. The application of this model on the literature data shows that by this model it becomes possible to identify the slowest and therefore rate determining step.
14 citations
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TL;DR: In this paper, a cost analysis revealed that the enzyme costs are negligible, but the cost for nicotinamide cofactor NADP+ is dominating the overall cost of the chemical raw material followed by the ionic liquid (TEGO IL K5) used as solubiliser and the buffer.
14 citations
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TL;DR: A thermal barrier coating (TBC) system was manufactured on a Mo-containing γ-TiAl-based alloy utilizing the halogen effect to ensure the formation of thin protective oxide scales as discussed by the authors.
Abstract: A thermal barrier coating (TBC) system was manufactured on a Mo-containing γ-TiAl-based alloy utilizing the halogen effect to ensure the formation of thin protective oxide scales. Samples of the TNM-B1 alloy were treated with fluorine using hydrofluoric acid, an F-polymer spray, or plasma immersion ion implantation. They were subsequently exposed to air at 900 °C for 24 h to form a thermally grown oxide (TGO) layer consisting mainly of alumina. Using electron-beam physical vapor deposition, ceramic topcoats of 7 wt% yttria partially stabilized zirconia were deposited on the pre-oxidized fluorinated samples. The lifetime of this TBC system was determined by performing thermal cycling tests at 900 and 1000 °C in air. At 900 °C, lifetimes exceeding 1000 cycles of 1 h dwell time at high temperature were measured. The F-polymer treatment proved to be the most effective fluorination method. For TNM-B1 samples fluorinated by the latter treatment, lifetimes up to 1000 cycles were also determined at 1000 °C. The TBC exhibited good adherence to the TGO consisting mainly of alumina. An Al-depleted zone developed with small precipitates of the AlF3 phase below the oxide scale. Transmission electron microscopy examinations of the Al-depleted zone revealed the formation of the cubic Z-phase (Ti5Al3O2) which transformed into the α2-Ti3Al phase with prolonged high temperature exposure.
14 citations
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TL;DR: In this paper, an experimental investigation of Corrosion Reactions by analysis of the Corrosions Products was conducted by following the Chemical Reaction Rate (CRR) following the rate of the Electrochemical CORrosion Reaction (ECR).
Abstract: The sections in this article are
Introduction
Experimental Investigation of Corrosion Reactions by Analysis of the Corrosion Products
Experimental Investigation of Corrosion Reactions by Following the Chemical Reaction Rate
Experimental Investigation of Corrosion Reactions by Following the Rate of the Electrochemical Corrosion Reaction
Electrochemical Impedance Spectroscopy and Noise Analysis
Introduction
The Principle of Dynamic System Analysis
Measurement of the Electrochemical Impedance
Presentation of Impedance Data
Interpretation of Impedance Data
The Polarization Resistance
Frequency Dispersion
Surface Inhomogeneities
Single Layer Impedance Model
Sandwich Layer Impedance Model
Equivalent Circuit Versus Transfer Function
The Transport Impedance
Iron Corrosion in Neutral Solution
Impedance Model of Passive Films
Metal Dissolution and Active-to-Passive Transition
Electrochemical Noise
Noise Sources in Electrochemical Systems
Noise Measurement Techniques
Data Processing
Noise Resistance and Polarization Resistance
The Scanning Vibrating Electrode Technique
Introduction
History of Scanning Reference Electrodes
Basic Principles of Localized Potential Mapping
Localized Electrochemical Impedance Spectroscopy (LEIS)
Applications of Modern Scanning Electrode Techniques
Local Breakdown of Passivity
Galvanic Corrosion
Inhibition
Microbiologically Influenced Corrosion
Protective Polymeric Coatings
Concluding Remarks
Scanning Kelvinprobe
Introduction
Theory of the Vibrating Condenser Method
The Relation between the Volta Potential Difference and Corrosion-Relevant Properties
Electrolyte Covered Metal Surfaces
Metals in Humid Air
Polymer-Coated Metals
Calibration of the Kelvinprobe
Application of the Kelvinprobe: Atmospheric Corrosion
Experimental
Results
Application of the Kelvinprobe: Corrosion Protection by Organic Coatings
Experimental
Polymer-Coated Steel
Polymer Coated Galvanized Steel
Polymer Coated Aluminum Alloys
Industrial Coatings
Application of the Kelvinprobe: Corrosion Protection by Modified Metal Surfaces
Metal Surfaces Modified by Monolayers of Organic Molecules
Metal Surfaces Modified by Ultra-Thin Plasma Polymers
Metal Surfaces Modified by Inorganic and Organic Layers
14 citations
Authors
Showing all 760 results
Name | H-index | Papers | Citations |
---|---|---|---|
Wolf B. Frommer | 105 | 345 | 30918 |
Michael W. Anderson | 101 | 808 | 63603 |
João Rocha | 93 | 1521 | 49472 |
Martin Muhler | 77 | 606 | 25850 |
Michael Hunger | 60 | 295 | 11370 |
Ivars Neretnieks | 44 | 224 | 7159 |
Michael Schütze | 40 | 343 | 6311 |
Jens Schrader | 38 | 129 | 4239 |
Roland Dittmeyer | 31 | 206 | 3762 |
Lei Li | 29 | 198 | 4003 |
Dirk Holtmann | 29 | 107 | 3033 |
Lasse Greiner | 26 | 74 | 1994 |
Klaus-Michael Mangold | 23 | 57 | 1590 |
A. Rahmel | 23 | 59 | 1967 |
Gerhard Kreysa | 22 | 78 | 1305 |