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Christophe Tg Petit - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical Synthesis of Ammonia Based on Co3Mo3N Catalyst and LiAlO2–(Li,Na,K)2CO3 Composite Electrolyte
Electrocatalysis, 2014Co-Authors: Ibrahim Ali Ahmed Amar, Rong Lan, Christophe Tg Petit, Shanwen TaoAbstract:Cobalt molybdenum nitride (Co3Mo3N) catalyst was synthesised through ammonolysis of the corresponding precursors by flowing pure Ammonia gas. The catalyst was characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Ammonia was successfully synthesised from wet hydrogen and dry nitrogen at atmospheric pressure using Co3Mo3N–Ag composite as cathode, Ag–Pd alloy as anode and LiAlO2–(Li/Na/K)2CO3 composite as an electrolyte. Ammonia Formation was investigated at 400, 425 and 450 °C, and the maximum observed Ammonia Formation rate was 3.27×10−10 mol s−1 cm−2 at 450 °C when applied at 0.8 V. The catalytic activity of Co3Mo3N for electrochemical Ammonia synthesis is lower than that of Pd. The successful synthesis of Ammonia demonstrates that LiAlO2–(Li/Na/K)2CO3 composite exhibits protonic or/and oxygen ion conduction.
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Electrochemical synthesis of Ammonia from wet nitrogen using La0.6Sr0.4FeO3−δ–Ce0.8Gd0.18Ca0.02O2−δ composite cathode
RSC Adv., 2014Co-Authors: Ibrahim Ali Ahmed Amar, Rong Lan, Christophe Tg Petit, Gregory Bruce Mann, Shanwen TaoAbstract:Electrochemical synthesis of Ammonia from wet nitrogen in an electrolytic cell using a La0.6Sr0.4FeO3−δ–Ce0.8Gd0.18Ca0.02O2−δ composite cathode and an oxide–carbonate composite electrolyte has been investigated. La0.6Sr0.4FeO3−δ was prepared via a combined EDTA–citrate complexing sol–gel process, characterised by X-ray diffraction and SEM. A tri-layer electrolytic cell was fabricated by a one-step dry-pressing and co-firing process. Ammonia was successfully synthesised from wet nitrogen under atmospheric pressure. Ammonia Formation was observed at 375, 400, 425 and 450 °C and the maximum Ammonia Formation rate of 7 × 10−11 mol s−1 cm−2 was observed at 400 °C when a voltage of 1.4 V was applied. This Ammonia Formation rate corresponds to a Faradaic efficiency of ∼0.14% at a current density of 14.25 mA cm−2.
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Electrochemical synthesis of Ammonia from wet nitrogen using La₀.₆Sr₀.₄FeO₃₋δ–Ce₀.₈Gd₀.₁₈Ca₀.₀₂O₂₋δ composite cathode
RSC Advances, 2014Co-Authors: Ibrahim Ali Ahmed Amar, Rong Lan, Christophe Tg Petit, Gregory Bruce Mann, Shanwen TaoAbstract:Electrochemical synthesis of Ammonia from wet nitrogen in an electrolytic cell using a La₀.₆Sr₀.₄FeO₃₋δ–Ce₀.₈Gd₀.₁₈Ca₀.₀₂O₂₋δ composite cathode and an oxide–carbonate composite electrolyte has been investigated. La₀.₆Sr₀.₄FeO₃₋δ was prepared via a combined EDTA–citrate complexing sol–gel process, characterised by X-ray diffraction and SEM. A tri-layer electrolytic cell was fabricated by a one-step dry-pressing and co-firing process. Ammonia was successfully synthesised from wet nitrogen under atmospheric pressure. Ammonia Formation was observed at 375, 400, 425 and 450 °C and the maximum Ammonia Formation rate of 7 × 10⁻¹¹ mol s⁻¹ cm⁻² was observed at 400 °C when a voltage of 1.4 V was applied. This Ammonia Formation rate corresponds to a Faradaic efficiency of ∼0.14% at a current density of 14.25 mA cm⁻².
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Solid-state electrochemical synthesis of Ammonia: a review
Journal of Solid State Electrochemistry, 2011Co-Authors: Ibrahim A. Amar, Christophe Tg PetitAbstract:Ammonia is one of the most produced chemicals worldwide, and it is not only a major end product but also an important energy storage intermediate. The solid-state electrochemical synthesis of Ammonia has the promise to overcome the limitations of the conventional catalytic reactors such as the limited conversion, severe environmental pollution and high energy consumption. Solid-state electrolytes either protonic or oxide ion conductors have been reviewed and particular emphasis is placed on their application to synthesise Ammonia. The highest rate of Ammonia Formation according to the type of electrolyte utilised were in the following order; solid polymers > Ce_0.8Gd_0.2O_2−δ-(Ca_3(PO_4)_2-K_3PO_4) composites > fluorites > perovskites > pyrochlores although the catalysts in electrodes also play an important role. The highest rate reported so far is found to be 1.13 × 10^−8 mol s^−1 cm^−2 at 80 °C with a potential of 2 V using Nafion membrane, SmFe_0.7Cu_0.1Ni_0.2O_3 (SFCN), and Ni-Ce_0.8Sm_0.2O_2−δ as solid electrolyte, cathode and anode, respectively. Synthesising Ammonia from steam and N_2, by-passing H_2 stage offers many advantages such as reduction of device numbers and then the overall costs. The factors affecting the rate of Ammonia Formation have been discussed as well.
Ibrahim Ali Ahmed Amar - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical Synthesis of Ammonia Based on Co3Mo3N Catalyst and LiAlO2–(Li,Na,K)2CO3 Composite Electrolyte
Electrocatalysis, 2014Co-Authors: Ibrahim Ali Ahmed Amar, Rong Lan, Christophe Tg Petit, Shanwen TaoAbstract:Cobalt molybdenum nitride (Co3Mo3N) catalyst was synthesised through ammonolysis of the corresponding precursors by flowing pure Ammonia gas. The catalyst was characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Ammonia was successfully synthesised from wet hydrogen and dry nitrogen at atmospheric pressure using Co3Mo3N–Ag composite as cathode, Ag–Pd alloy as anode and LiAlO2–(Li/Na/K)2CO3 composite as an electrolyte. Ammonia Formation was investigated at 400, 425 and 450 °C, and the maximum observed Ammonia Formation rate was 3.27×10−10 mol s−1 cm−2 at 450 °C when applied at 0.8 V. The catalytic activity of Co3Mo3N for electrochemical Ammonia synthesis is lower than that of Pd. The successful synthesis of Ammonia demonstrates that LiAlO2–(Li/Na/K)2CO3 composite exhibits protonic or/and oxygen ion conduction.
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synthesis of Ammonia directly from wet air at intermediate temperature
Applied Catalysis B-environmental, 2014Co-Authors: Khaled A Alkhazmi, Ibrahim Ali Ahmed AmarAbstract:Abstract For the first time, Ammonia has been directly synthesised from wet air at intermediate temperature. Ce0.8Gd0.2O2−δ (CGO)–(Li,Na,K)2CO3 electrolyte together with a new perovskite oxide Pr0.6Ba0.4Fe0.8Cu0.2O3−δ were used for electrochemical synthesis of Ammonia. An Ammonia Formation rate of 1.07 × 10−6 mol s−1 m−2 was obtained at 400 °C when applied a voltage of 1.4 V, while wet air was introduced to the single chamber reactor. This is just slightly lower than the value of 1.83 × 10−6 mol s−1 m−2 when wet N2 was fed under the same experimental conditions. These values are two to three orders of magnitude higher than the reported Ammonia Formation rates when synthesised from N2 and H2O at ∼600 °C. The perovskite catalysts are also low cost compared to the Ru/MgO and Pt/C catalysts in previous reports.
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Electrochemical synthesis of Ammonia from wet nitrogen using La0.6Sr0.4FeO3−δ–Ce0.8Gd0.18Ca0.02O2−δ composite cathode
RSC Adv., 2014Co-Authors: Ibrahim Ali Ahmed Amar, Rong Lan, Christophe Tg Petit, Gregory Bruce Mann, Shanwen TaoAbstract:Electrochemical synthesis of Ammonia from wet nitrogen in an electrolytic cell using a La0.6Sr0.4FeO3−δ–Ce0.8Gd0.18Ca0.02O2−δ composite cathode and an oxide–carbonate composite electrolyte has been investigated. La0.6Sr0.4FeO3−δ was prepared via a combined EDTA–citrate complexing sol–gel process, characterised by X-ray diffraction and SEM. A tri-layer electrolytic cell was fabricated by a one-step dry-pressing and co-firing process. Ammonia was successfully synthesised from wet nitrogen under atmospheric pressure. Ammonia Formation was observed at 375, 400, 425 and 450 °C and the maximum Ammonia Formation rate of 7 × 10−11 mol s−1 cm−2 was observed at 400 °C when a voltage of 1.4 V was applied. This Ammonia Formation rate corresponds to a Faradaic efficiency of ∼0.14% at a current density of 14.25 mA cm−2.
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Electrochemical synthesis of Ammonia from wet nitrogen using La₀.₆Sr₀.₄FeO₃₋δ–Ce₀.₈Gd₀.₁₈Ca₀.₀₂O₂₋δ composite cathode
RSC Advances, 2014Co-Authors: Ibrahim Ali Ahmed Amar, Rong Lan, Christophe Tg Petit, Gregory Bruce Mann, Shanwen TaoAbstract:Electrochemical synthesis of Ammonia from wet nitrogen in an electrolytic cell using a La₀.₆Sr₀.₄FeO₃₋δ–Ce₀.₈Gd₀.₁₈Ca₀.₀₂O₂₋δ composite cathode and an oxide–carbonate composite electrolyte has been investigated. La₀.₆Sr₀.₄FeO₃₋δ was prepared via a combined EDTA–citrate complexing sol–gel process, characterised by X-ray diffraction and SEM. A tri-layer electrolytic cell was fabricated by a one-step dry-pressing and co-firing process. Ammonia was successfully synthesised from wet nitrogen under atmospheric pressure. Ammonia Formation was observed at 375, 400, 425 and 450 °C and the maximum Ammonia Formation rate of 7 × 10⁻¹¹ mol s⁻¹ cm⁻² was observed at 400 °C when a voltage of 1.4 V was applied. This Ammonia Formation rate corresponds to a Faradaic efficiency of ∼0.14% at a current density of 14.25 mA cm⁻².
Angela Schwarm - One of the best experts on this subject based on the ideXlab platform.
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In vitro ruminal fermentation and methane inhibitory effect of three species of microalgae
Canadian Journal of Animal Science, 2020Co-Authors: Ali Kiani, Michael Kreuzer, Lukas Eggerschwiler, Christina Wolf, Katrin Giller, Angela SchwarmAbstract:In this study, in vitro ruminal fermentation, anti-methanogenesis, and Ammonia Formation of two autotrophic algae [Nannochloropsis gaditana (NG), Phaeodactylum tricornutum (PT)], and one heterotrop...
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Dose-response effects of woody and herbaceous forage plants on in vitro ruminal methane and Ammonia Formation, and their short-term palatability in lactating cows
animal, 2019Co-Authors: Melissa Terranova, Michael Kreuzer, Ueli Braun, Shaopu Wang, Lukas Eggerschwiler, Angela SchwarmAbstract:Plant secondary compounds ( PSC ) are prevalent in many woody, temperate-climate plant species and play a crucial role in dietary attempts to mitigate methane emissions in ruminants. However, their application requires sufficient palatability and feeding value. In the present study, leaves from silver birch ( Betula pendula ), hazel ( Corylus avellana ), blackcurrant ( Ribes nigrum ), green grape vine ( Vitis vinifera ) and the herbs rosebay willow ( Epilobium angustifolium ) and wood avens ( Geum urbanum ) were tested in various doses with the Hohenheim gas test method in vitro and their short-term palatability in dairy cows. For the palatability experiment, the plants were pelleted with lucerne in different proportions to obtain the same phenol content, but realised contents differed from expected contents. The pellets were provided separately from a mixed basal ration (0.4 : 0.6) to each cow, in a randomised order, for 3 days per plant. All plants mitigated in vitro methane and Ammonia Formation, often in a linear dose response. These levels of effects differed among plants. Significant effects were observed at 100 (hazel, rosebay willow) to 400 g/kg of plant material. The test plants had a lower feeding value than the high-quality basal diet. This was indicated by in vitro organic matter digestibility, short-chain fatty acid Formation and calculated contents of net energy of lactation. Simultaneously, the linear depression of Ammonia Formation indicated a dose-dependent increase of utilisable CP. Only blackcurrant and birch were less preferred to lucerne. However, this aversion subsided on day 3 of offer. The rosebay willow pellets had the highest phenol content but were not the least palatable. Accordingly, PSC may not be the main determinants of palatability for the plants tested. Plants did not differ significantly in their short-term effects on milk yield and composition, and all of the plants substantially reduced milk urea content. Overall, the results suggest that hazel and vine leaves, and rosebay willow and wood avens herbs should be tested for their potential to mitigate methane and N emissions in vivo .
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In vitro screening of temperate climate forages from a variety of woody plants for their potential to mitigate ruminal methane and Ammonia Formation
The Journal of Agricultural Science, 2018Co-Authors: Melissa Terranova, Michael Kreuzer, Ueli Braun, Angela SchwarmAbstract:Feeding phenol-containing plants to ruminants has the potential to mitigate both methane and Ammonia Formation. In the present study, mostly woody plants, such as the leaves of trees and shrubs, were tested for their influence on in vitro fermentation. The plants selected grow naturally under temperate climatic conditions, are usually available in bulk and do not directly compete with human food production. The detailed screening included whole plants or parts of different plant species reporting their effects on methane and/or Ammonia Formation. The plant materials were added at 167 mg/g of total dry matter (DM) to a common total mixed ration and incubated for 24 h with the Hohenheim gas test method. The results from in vitro fermentation were also used to determine the net energy of lactation and utilizable crude protein in the complete diets. Thirteen out of 18 test materials did not impair the organic matter (OM) digestibility of the diet. Ammonia concentrations decreased up to 35% when adding any of the test materials. Methane Formation per unit of feed DM and per unit of digestible OM was lowered by 13 of the 18 test materials from 12 to 28% and 5 to 20%, respectively. In conclusion, a number of plant materials tested have the potential to mitigate ruminal Ammonia and methane Formation without adversely affecting digestibility. The leaves of Betula pendula , Corylus avellana , Ribes nigrum , Vitis vinifera and the aerial part of Geum urbanum were particularly promising in this respect.
Francisco L. Tabarés - One of the best experts on this subject based on the ideXlab platform.
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Role of nitrogen inventory and ion enhanced N-H recombination in the Ammonia Formation on tungsten walls. A DC glow discharge study
Vacuum, 2018Co-Authors: A. De Castro, Francisco L. TabarésAbstract:Abstract Dedicated studies using Glow Discharge plasmas on tungsten (W) walls have been carried-out, trying to understand the surface chemistry and the underlying processes behind the mechanism of the Ammonia Formation that takes place during nitrogen (N2) seeded discharges on the inner walls of magnetic nuclear fusion devices. The experiments with pure deuterium (D2) plasma irradiation on a cold rolled tungsten sheet (previously irradiated with pure N2 plasma) at 150 °C showed the Formation of deuterated Ammonia as a result of the interaction between the trapped nitrogen atoms and the impinging deuterium on the surface. Conversely, the symmetric experiment based on the irradiation of the tungsten wall (previously irradiated with D2 plasma) with N2 plasma did not show significant Ammonia production, thus suggesting that the presence of nitrogen on the surface is the first and crucial step in the Ammonia Formation mechanism. The study was completed with experiments that employed N2-H2-(Helium) mixed plasmas trying to understand the role of the helium bombardment (unavoidable in a Deuterium-Tritium fusion reactor) in the N-H recombination. An enhancement in Ammonia generation up to a 45% was observed with increasing helium plasma contents.
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Influence of residence time and helium addition in the Ammonia Formation on tungsten walls in N2H2 glow discharge plasmas
Nuclear Materials and Energy, 2017Co-Authors: A. De Castro, D. Alegre, Francisco L. TabarésAbstract:Abstract The influence of the residence time for the active species and of the helium addition to the plasma in the Ammonia Formation in N2 H2 (He) Glow Discharge plasmas has been studied using differential pumped mass spectrometry. Three different residence times for the N2 molecule were studied: 25, 50 and 100 ms. Other experiments scanning the helium plasma content (0–8%) were performed with a residence time of 100 ms. While no difference in the Ammonia Formation yields was found between the cases of 25 ms and 50 ms, the Ammonia yields were increased by a 25% in the case of 100 ms. Additionally, an increasing helium plasma content enhances the Ammonia Formation yields up to 45%. Three different effects induced by the presence of helium in the plasma were analyzed: effects in mass spectrometry measurements, changes in the electron temperature and modification of the surface chemistry. The analyzes pointed out to an improved N H recombination on tungsten walls induced by helium presence as the key factor that could explain the higher Ammonia yields experimentally found for the highest helium content in the plasma.
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Ammonia Formation in N2/H2 plasmas on ITER-relevant plasma facing materials: Surface temperature and N2 plasma content effects
Journal of Nuclear Materials, 2015Co-Authors: A. De Castro, D. Alegre, Francisco L. TabarésAbstract:Abstract Ammonia production in N 2 /H 2 direct current glow discharge plasmas, with nitrogen concentrations from 1.5% to 33%, different wall materials (tungsten, stainless steel and aluminium as a proxy for beryllium) and surface temperatures up to 350 °C has been investigated. Ammonia yields on the exposed materials have been deduced, resulting in different values depending on the wall material, its temperature and N 2 plasma content. The results indicate weak wall temperature dependence in tungsten and stainless steel. However, wall temperatures above 300 °C have a very clear influence on aluminium walls, as almost all the molecular N 2 depleted from the gas phase is converted into Ammonia. The amount of implanted N seems to have a direct impact on the Ammonia Formation yield, pointing to the competition between N implantation and N/H–N/N recombination on the walls as the key mechanism of the Ammonia Formation.
Michael Kreuzer - One of the best experts on this subject based on the ideXlab platform.
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In vitro ruminal fermentation and methane inhibitory effect of three species of microalgae
Canadian Journal of Animal Science, 2020Co-Authors: Ali Kiani, Michael Kreuzer, Lukas Eggerschwiler, Christina Wolf, Katrin Giller, Angela SchwarmAbstract:In this study, in vitro ruminal fermentation, anti-methanogenesis, and Ammonia Formation of two autotrophic algae [Nannochloropsis gaditana (NG), Phaeodactylum tricornutum (PT)], and one heterotrop...
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Combination Effects of Plant Extracts Rich in Tannins and Saponins as Feed Additives for Mitigating in Vitro Ruminal Methane and Ammonia Formation.
Animals, 2020Co-Authors: Anuraga Jayanegara, Yogianto Yogianto, Elizabeth Wina, Asep Sudarman, Makoto Kondo, Taketo Obitsu, Michael KreuzerAbstract:The objective of this experiment was to test the effects of combining plant extracts rich in tannins and saponins at varying proportions on in vitro ruminal methane and Ammonia Formation. Tannins were extracted from Swietenia mahogani leaves and saponins from Sapindus rarak fruits with various solvents. The extracts obtained with the most efficient solvents (tannins: 75% water and 25% methanol; saponins: pure methanol) were then used in vitro. The treatments consisted of two substrate types (high-forage (HF) or high-concentrate (HC) diets) and five extract combinations (tannins: saponins, 1:0, 3:1, 1:1, 1:3, and 0:1) added at 2 mg/mL in incubation liquid. In vitro incubation was performed in four runs, with each treatment being represented with two replicates per run. The addition of plant extracts rich in tannins and saponins, either individually or in combination, decreased the methane proportion of total gas in both the HF (p < 0.05) and HC (p < 0.05) diets. The effects of the plant extracts rich in tannins and saponins were generally additive in mitigating methane emissions. Favorable associative effects between the extracts were observed in the Ammonia concentration, both in the HF (p < 0.001) and HC (p < 0.01) diets and in the methane proportion of total gas, with a 1:3 mixture of tannins and saponins added to the HC diet (p < 0.05).
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Dose-response effects of woody and herbaceous forage plants on in vitro ruminal methane and Ammonia Formation, and their short-term palatability in lactating cows
animal, 2019Co-Authors: Melissa Terranova, Michael Kreuzer, Ueli Braun, Shaopu Wang, Lukas Eggerschwiler, Angela SchwarmAbstract:Plant secondary compounds ( PSC ) are prevalent in many woody, temperate-climate plant species and play a crucial role in dietary attempts to mitigate methane emissions in ruminants. However, their application requires sufficient palatability and feeding value. In the present study, leaves from silver birch ( Betula pendula ), hazel ( Corylus avellana ), blackcurrant ( Ribes nigrum ), green grape vine ( Vitis vinifera ) and the herbs rosebay willow ( Epilobium angustifolium ) and wood avens ( Geum urbanum ) were tested in various doses with the Hohenheim gas test method in vitro and their short-term palatability in dairy cows. For the palatability experiment, the plants were pelleted with lucerne in different proportions to obtain the same phenol content, but realised contents differed from expected contents. The pellets were provided separately from a mixed basal ration (0.4 : 0.6) to each cow, in a randomised order, for 3 days per plant. All plants mitigated in vitro methane and Ammonia Formation, often in a linear dose response. These levels of effects differed among plants. Significant effects were observed at 100 (hazel, rosebay willow) to 400 g/kg of plant material. The test plants had a lower feeding value than the high-quality basal diet. This was indicated by in vitro organic matter digestibility, short-chain fatty acid Formation and calculated contents of net energy of lactation. Simultaneously, the linear depression of Ammonia Formation indicated a dose-dependent increase of utilisable CP. Only blackcurrant and birch were less preferred to lucerne. However, this aversion subsided on day 3 of offer. The rosebay willow pellets had the highest phenol content but were not the least palatable. Accordingly, PSC may not be the main determinants of palatability for the plants tested. Plants did not differ significantly in their short-term effects on milk yield and composition, and all of the plants substantially reduced milk urea content. Overall, the results suggest that hazel and vine leaves, and rosebay willow and wood avens herbs should be tested for their potential to mitigate methane and N emissions in vivo .
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In vitro screening of temperate climate forages from a variety of woody plants for their potential to mitigate ruminal methane and Ammonia Formation
The Journal of Agricultural Science, 2018Co-Authors: Melissa Terranova, Michael Kreuzer, Ueli Braun, Angela SchwarmAbstract:Feeding phenol-containing plants to ruminants has the potential to mitigate both methane and Ammonia Formation. In the present study, mostly woody plants, such as the leaves of trees and shrubs, were tested for their influence on in vitro fermentation. The plants selected grow naturally under temperate climatic conditions, are usually available in bulk and do not directly compete with human food production. The detailed screening included whole plants or parts of different plant species reporting their effects on methane and/or Ammonia Formation. The plant materials were added at 167 mg/g of total dry matter (DM) to a common total mixed ration and incubated for 24 h with the Hohenheim gas test method. The results from in vitro fermentation were also used to determine the net energy of lactation and utilizable crude protein in the complete diets. Thirteen out of 18 test materials did not impair the organic matter (OM) digestibility of the diet. Ammonia concentrations decreased up to 35% when adding any of the test materials. Methane Formation per unit of feed DM and per unit of digestible OM was lowered by 13 of the 18 test materials from 12 to 28% and 5 to 20%, respectively. In conclusion, a number of plant materials tested have the potential to mitigate ruminal Ammonia and methane Formation without adversely affecting digestibility. The leaves of Betula pendula , Corylus avellana , Ribes nigrum , Vitis vinifera and the aerial part of Geum urbanum were particularly promising in this respect.
