18 results on '"Nørskov, A. K."'
Search Results
2. Calcium-mediated nitrogen reduction for electrochemical ammonia synthesis
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Fu, Xianbiao, Niemann, Valerie A., Zhou, Yuanyuan, Li, Shaofeng, Zhang, Ke, Pedersen, Jakob B., Saccoccio, Mattia, Andersen, Suzanne Z., Enemark-Rasmussen, Kasper, Benedek, Peter, Xu, Aoni, Deissler, Niklas H., Mygind, Jon Bjarke Valbæk, Nielander, Adam C., Kibsgaard, Jakob, Vesborg, Peter C. K., Nørskov, Jens K., Jaramillo, Thomas F., and Chorkendorff, Ib
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- 2024
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3. Combined Dexamethasone and Dexmedetomidine as Adjuncts to Popliteal and Saphenous Nerve Blocks in Patients Undergoing Surgery of the Foot or Ankle: A Randomized, Blinded, Placebo-controlled, Clinical Trial
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Maagaard, Mathias, Funder, Kamilia S., Schou, Nikolaj K., Penny, Jeannette Ø., Toquer, Peter, Laigaard, Jens, Stormholt, Emma R., Nørskov, Anders K., Jæger, Pia, Andersen, Jakob H., and Mathiesen, Ole
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- 2024
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4. CO Methanation over Ni-Fe Alloy Catalysts: An Inverse Design Problem.
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Wenqiang Yang, Zhenbin Wang, and Nørskov, Jens K.
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- 2024
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5. Phenol as proton shuttle and buffer for lithium-mediated ammonia electrosynthesis
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Fu, Xianbiao, primary, Xu, Aoni, additional, Pedersen, Jakob B., additional, Li, Shaofeng, additional, Sažinas, Rokas, additional, Zhou, Yuanyuan, additional, Andersen, Suzanne Z., additional, Saccoccio, Mattia, additional, Deissler, Niklas H., additional, Mygind, Jon Bjarke Valbæk, additional, Kibsgaard, Jakob, additional, Vesborg, Peter C. K., additional, Nørskov, Jens K., additional, and Chorkendorff, Ib, additional
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- 2024
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6. Combined Dexamethasone and Dexmedetomidine as Adjuncts to Popliteal and Saphenous Nerve Blocks in Patients Undergoing Surgery of the Foot or Ankle:A Randomized, Blinded, Placebo-controlled Clinical Trial
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Maagaard, Mathias, Funder, Kamilia S., Schou, Nikolaj K., Penny, Jeannette, Toquer, Peter, Laigaard, Jens, Stormholt, Emma R., Nørskov, Anders K., Jæger, Pia, Andersen, Jakob H., Mathiesen, Ole, Maagaard, Mathias, Funder, Kamilia S., Schou, Nikolaj K., Penny, Jeannette, Toquer, Peter, Laigaard, Jens, Stormholt, Emma R., Nørskov, Anders K., Jæger, Pia, Andersen, Jakob H., and Mathiesen, Ole
- Abstract
Background Both dexamethasone and dexmedetomidine increase the duration of analgesia of peripheral nerve blocks. The authors hypothesized that combined intravenous dexamethasone and intravenous dexmedetomidine would result in a greater duration of analgesia when compared with intravenous dexamethasone alone and placebo. Methods The authors randomly allocated participants undergoing surgery of the foot or ankle under general anesthesia and with a combined popliteal (sciatic) and saphenous nerve block to a combination of 12 mg dexamethasone and 1 µg/kg dexmedetomidine, 12 mg dexamethasone, or placebo (saline). The primary outcome was the duration of analgesia measured as the time from block performance until the first sensation of pain in the surgical area as reported by the participant. The authors predefined a 33% difference in the duration of analgesia as clinically relevant. Results A total of 120 participants from two centers were randomized and 119 analyzed for the primary outcome. The median [interquartile range] duration of analgesia was 1,572 min [1,259 to 1,715] with combined dexamethasone and dexmedetomidine, 1,400 min [1,133 to 1,750] with dexamethasone alone, and 870 min [748 to 1,138] with placebo. Compared with placebo, the duration was greater with combined dexamethasone and dexmedetomidine (difference, 564 min; 98.33% CI, 301 to 794; P < 0.001) and with dexamethasone (difference, 489 min; 98.33% CI, 265 to 706; P < 0.001). The prolongations exceeded the authors’ predefined clinically relevant difference. The duration was similar when combined dexamethasone and dexmedetomidine was compared with dexamethasone alone (difference, 61 min; 98.33% CI, –222 to 331; P = 0.614). Conclusions Dexamethasone with or without dexmedetomidine increased the duration of analgesia in patients undergoing surgery of the foot or ankle with a popliteal (sciatic) and saphenous nerve block. Combined dexamethasone and dexmedetomi, BACKGROUND: Both dexamethasone and dexmedetomidine increase the duration of analgesia of peripheral nerve blocks. The authors hypothesized that combined intravenous dexamethasone and intravenous dexmedetomidine would result in a greater duration of analgesia when compared with intravenous dexamethasone alone and placebo. METHODS: The authors randomly allocated participants undergoing surgery of the foot or ankle under general anesthesia and with a combined popliteal (sciatic) and saphenous nerve block to a combination of 12 mg dexamethasone and 1 µg/kg dexmedetomidine, 12 mg dexamethasone, or placebo (saline). The primary outcome was the duration of analgesia measured as the time from block performance until the first sensation of pain in the surgical area as reported by the participant. The authors predefined a 33% difference in the duration of analgesia as clinically relevant. RESULTS: A total of 120 participants from two centers were randomized and 119 analyzed for the primary outcome. The median [interquartile range] duration of analgesia was 1,572 min [1,259 to 1,715] with combined dexamethasone and dexmedetomidine, 1,400 min [1,133 to 1,750] with dexamethasone alone, and 870 min [748 to 1,138] with placebo. Compared with placebo, the duration was greater with combined dexamethasone and dexmedetomidine (difference, 564 min; 98.33% CI, 301 to 794; P < 0.001) and with dexamethasone (difference, 489 min; 98.33% CI, 265 to 706; P < 0.001). The prolongations exceeded the authors' predefined clinically relevant difference. The duration was similar when combined dexamethasone and dexmedetomidine was compared with dexamethasone alone (difference, 61 min; 98.33% CI, -222 to 331; P = 0.614). CONCLUSIONS: Dexamethasone with or without dexmedetomidine increased the duration of analgesia in patients undergoing surgery of the foot or ankle with a popliteal (sciatic) and saphenous nerve block. Combined dexamethasone and dexmedetomidine did not increase the duration o
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- 2024
7. Peripheral nerve blocks for closed reduction of distal radius fractures—A protocol for a systematic review
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Pisljagic, Sanja, Temberg, Jens L., Steensbæk, Mathias T., Yousef, Sina, Maagaard, Mathias, Chafranska, Lana, Lange, Kai H.W., Rothe, Christian, Lundstrøm, Lars H., Nørskov, Anders K., Pisljagic, Sanja, Temberg, Jens L., Steensbæk, Mathias T., Yousef, Sina, Maagaard, Mathias, Chafranska, Lana, Lange, Kai H.W., Rothe, Christian, Lundstrøm, Lars H., and Nørskov, Anders K.
- Abstract
Background Current methods of anaesthesia used for closed reduction of distal radial fractures may be insufficient for pain relief and muscle relaxation, potentially compromising reduction quality and patient satisfaction. Peripheral nerve blocks have already been implemented for surgery of wrist fractures and may provide optimal conditions for closed reduction due to complete motor and sensory blockade of the involved nerves. However, existing literature on peripheral nerve blocks for closed reduction is sparse, and no updated systematic review or meta-analysis exists. Aims This protocol is developed according to the PRISMA-P statement. The systematic review and meta-analysis aim to consolidate the literature regarding the effect and harm of peripheral nerve blocks compared with other anaesthesia modalities for closed reduction of distal radius fractures in adults. Methods The two primary outcomes are the proportion of participants needing surgery after closed reduction and pain during closed reduction. We will only include randomised clinical trials. Two review authors will each independently screen literature, extract data, and assess risk of bias with Risk of Bias 2 Tool. Meta-analysis will be carried out with Rstudio. We will also perform a Trial Sequential Analysis. The certainty of evidence will be judged using GRADE guidelines. Discussion We will use up-to-date methodology when conducting the systematic review outlined in this protocol. The results may guide clinicians in their decision-making regarding the use of anaesthesia for closed reduction of distal radius fractures in adults., Background: Current methods of anaesthesia used for closed reduction of distal radial fractures may be insufficient for pain relief and muscle relaxation, potentially compromising reduction quality and patient satisfaction. Peripheral nerve blocks have already been implemented for surgery of wrist fractures and may provide optimal conditions for closed reduction due to complete motor and sensory blockade of the involved nerves. However, existing literature on peripheral nerve blocks for closed reduction is sparse, and no updated systematic review or meta-analysis exists. Aims: This protocol is developed according to the PRISMA-P statement. The systematic review and meta-analysis aim to consolidate the literature regarding the effect and harm of peripheral nerve blocks compared with other anaesthesia modalities for closed reduction of distal radius fractures in adults. Methods: The two primary outcomes are the proportion of participants needing surgery after closed reduction and pain during closed reduction. We will only include randomised clinical trials. Two review authors will each independently screen literature, extract data, and assess risk of bias with Risk of Bias 2 Tool. Meta-analysis will be carried out with Rstudio. We will also perform a Trial Sequential Analysis. The certainty of evidence will be judged using GRADE guidelines. Discussion: We will use up-to-date methodology when conducting the systematic review outlined in this protocol. The results may guide clinicians in their decision-making regarding the use of anaesthesia for closed reduction of distal radius fractures in adults.
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- 2024
8. Mixing short- and long-acting local anaesthetics in peripheral nerve blocks:Protocol for a systematic review and meta-analysis
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Temberg, Jens L., Pisljagic, Sanja, Steensbæk, Mathias T., Yousef, Sina, Chafranska, Lana, Lange, Kai H.W., Rothe, Christian, Nørskov, Anders K., Maagaard, Mathias, Lundstrøm, Lars H., Temberg, Jens L., Pisljagic, Sanja, Steensbæk, Mathias T., Yousef, Sina, Chafranska, Lana, Lange, Kai H.W., Rothe, Christian, Nørskov, Anders K., Maagaard, Mathias, and Lundstrøm, Lars H.
- Abstract
Introduction This protocol describes a systematic review and meta-analysis to evaluate the clinical effects of mixing short- and long-acting local anaesthetics in peripheral nerve blocks. Clinicians often combine short- and long-acting local anaesthetics to achieve a briefer onset time. However, this may come with a prize, namely a shorter total duration of the block, which is of clinical importance. Objective This systematic review aims to strengthen the knowledge of the clinical effects associated with this practice. The primary outcome is the duration of block analgesia. Secondary outcomes are block onset time, sensory and motor block duration. Exploratory outcomes are postoperative pain scores, cumulative 24-h opioid consumption and the prevalence of serious adverse events. Methods We will conduct a meta-analysis of the extracted data, and the risk of bias for each study will be evaluated. We will perform a Trial Sequential Analysis, subgroup, and sensitivity analyses and assess the overall risk of publication bias. Finally, we will evaluate the review using the GRADE principles., Introduction: This protocol describes a systematic review and meta-analysis to evaluate the clinical effects of mixing short- and long-acting local anaesthetics in peripheral nerve blocks. Clinicians often combine short- and long-acting local anaesthetics to achieve a briefer onset time. However, this may come with a prize, namely a shorter total duration of the block, which is of clinical importance. Objective: This systematic review aims to strengthen the knowledge of the clinical effects associated with this practice. The primary outcome is the duration of block analgesia. Secondary outcomes are block onset time, sensory and motor block duration. Exploratory outcomes are postoperative pain scores, cumulative 24-h opioid consumption and the prevalence of serious adverse events. Methods: We will conduct a meta-analysis of the extracted data, and the risk of bias for each study will be evaluated. We will perform a Trial Sequential Analysis, subgroup, and sensitivity analyses and assess the overall risk of publication bias. Finally, we will evaluate the review using the GRADE principles.
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- 2024
9. New challenges in oxygen reduction catalysis: a consortium retrospective to inform future research
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Stevens, Michaela Burke, Anand, Megha, Kreider, Melissa E., Price, Eliza K., Zeledón, José Zamara, Wang, Liang, Peng, Jiayu, Li, Hao, Gregoire, John M., Hummelshøj, Jens, Jaramillo, Thomas F., Jia, Hongfei, Nørskov, Jens K., Roman-Leshkov, Yuriy, Shao-Horn, Yang, Storey, Brian D., Suram, Santosh K., Torrisi, Steven B., Montoya, Joseph H., Stevens, Michaela Burke, Anand, Megha, Kreider, Melissa E., Price, Eliza K., Zeledón, José Zamara, Wang, Liang, Peng, Jiayu, Li, Hao, Gregoire, John M., Hummelshøj, Jens, Jaramillo, Thomas F., Jia, Hongfei, Nørskov, Jens K., Roman-Leshkov, Yuriy, Shao-Horn, Yang, Storey, Brian D., Suram, Santosh K., Torrisi, Steven B., and Montoya, Joseph H.
- Abstract
In this perspective, we highlight results of a research consortium devoted to advancing understanding of oxygen reduction reaction (ORR) catalysis as a means to inform fuel cell science. We demonstrate how targeted collaborations between different institutions from academic, national lab, and industry backgrounds and different scientific disciplines like theory, experiment, and characterization can yield unique insights into fuel cell catalysts. We comment on such insights into material designs for platinum-group-metal alloys, transition metal oxides, and non-traditional materials including metal–organic frameworks; systems that have served as the foundational building blocks for our consortium. We also motivate a renewed focus on catalyst durability in light of emerging technological requirements and paths forward in understanding in situ and operando electrochemical stability. Finally, we describe new frontiers ORR research can take and how emerging artificial intelligence tools can assist researchers in capturing data, selecting new experiments, and guiding characterization to accelerate the design and discovery of fuel cell catalysts. A main goal of sharing this perspective is to discuss the rationale for our future research plans based on our consortium work. However, we also hope to illustrate both the potential impact of a collaborative strategy with the hopes of inspiring a higher degree of Industry-Academia-National Laboratory collaboration and encourage other centers and consortiums to distill and share their findings in a similar perspective-type article. Together we hope to enable the fuel cell research community to engage in a discussion of strategies for research and accelerated development of catalysts with improved activity and stability.
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- 2024
10. Phenol as proton shuttle and buffer for lithium-mediated ammonia electrosynthesis
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Fu, Xianbiao, Xu, Aoni, Pedersen, Jakob B., Li, Shaofeng, Sažinas, Rokas, Zhou, Yuanyuan, Andersen, Suzanne Z., Saccoccio, Mattia, Deissler, Niklas H., Mygind, Jon Bjarke Valbæk, Kibsgaard, Jakob, Vesborg, Peter C.K., Nørskov, Jens K., Chorkendorff, Ib, Fu, Xianbiao, Xu, Aoni, Pedersen, Jakob B., Li, Shaofeng, Sažinas, Rokas, Zhou, Yuanyuan, Andersen, Suzanne Z., Saccoccio, Mattia, Deissler, Niklas H., Mygind, Jon Bjarke Valbæk, Kibsgaard, Jakob, Vesborg, Peter C.K., Nørskov, Jens K., and Chorkendorff, Ib
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Ammonia is a crucial component in the production of fertilizers and various nitrogen-based compounds. Now, the lithium-mediated nitrogen reduction reaction (Li-NRR) has emerged as a promising approach for ammonia synthesis at ambient conditions. The proton shuttle plays a critical role in the proton transfer process during Li-NRR. However, the structure-activity relationship and design principles for effective proton shuttles have not yet been established in practical Li-NRR systems. Here, we propose a general procedure for verifying a true proton shuttle and established design principles for effective proton shuttles. We systematically evaluate several classes of proton shuttles in a continuous-flow reactor with hydrogen oxidation at the anode. Among the tested proton shuttles, phenol exhibits the highest Faradaic efficiency of 72 ± 3% towards ammonia, surpassing that of ethanol, which has been commonly used so far. Experimental investigations including operando isotope-labelled mass spectrometry proved the proton-shuttling capability of phenol. Further mass transport modeling sheds light on the mechanism.
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- 2024
11. Characterization of adsorption sites on IrO2via temperature programmed O2 desorption simulations.
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Ocampo-Restrepo, Vivianne K., Vijay, Sudarshan, Gunasooriya, G. T. Kasun Kalhara, and Nørskov, Jens K.
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This study presents simulations of temperature-programmed desorption (TPD) profiles using desorption energy data from density functional theory (DFT) calculations. We apply this method to investigate the desorption of oxygen (O
2 ) from IrO2 (110) to gain insight into the kinetics of oxygen coupling and desorption, important elementary steps in the oxygen evolution reaction (OER). Initially, we confirm the thermodynamically stable adsorption site for oxygen in the pristine IrO2 (110) as IrCUS , even with a high oxygen coverage. We successfully simulate TPD for O2 desorption, achieving good agreement with experimental TPD data for different initial oxygen exposures when including more than one adsorption site. We identify a new adsorption site, related to the formation of steps on IrO2 (110)(IrCUS-step-0.5 ), that is essential for reproducing the experimental TPD. Our findings suggest that the observed TPD peaks are the result of different adsorption sites on the surface, rather than solely a lateral interactions effect. This work provides insight into the behavior of oxygen adsorption on IrO2 , with implications for understanding surface reactivity and catalytic processes involving this material. [ABSTRACT FROM AUTHOR]- Published
- 2024
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12. Spin-mediated promotion of Co catalysts for ammonia synthesis.
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Ke Zhang, Ang Cao, Wandall, Lau Halkier, Vernieres, Jerome, Kibsgaard, Jakob, Nørskov, Jens K., and Chorkendorff, Ib
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- 2024
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13. Mixing short‐ and long‐acting local anaesthetics in peripheral nerve blocks: Protocol for a systematic review and meta‐analysis.
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Temberg, Jens L., Pisljagic, Sanja, Steensbæk, Mathias T., Yousef, Sina, Chafranska, Lana, Lange, Kai H. W., Rothe, Christian, Nørskov, Anders K., Maagaard, Mathias, and Lundstrøm, Lars H.
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PERIPHERAL nervous system ,RESEARCH protocols ,ANESTHETICS ,NERVE block ,SEQUENTIAL analysis ,POSTOPERATIVE pain - Abstract
Introduction: This protocol describes a systematic review and meta‐analysis to evaluate the clinical effects of mixing short‐ and long‐acting local anaesthetics in peripheral nerve blocks. Clinicians often combine short‐ and long‐acting local anaesthetics to achieve a briefer onset time. However, this may come with a prize, namely a shorter total duration of the block, which is of clinical importance. Objective: This systematic review aims to strengthen the knowledge of the clinical effects associated with this practice. The primary outcome is the duration of block analgesia. Secondary outcomes are block onset time, sensory and motor block duration. Exploratory outcomes are postoperative pain scores, cumulative 24‐h opioid consumption and the prevalence of serious adverse events. Methods: We will conduct a meta‐analysis of the extracted data, and the risk of bias for each study will be evaluated. We will perform a Trial Sequential Analysis, subgroup, and sensitivity analyses and assess the overall risk of publication bias. Finally, we will evaluate the review using the GRADE principles. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Formic Acid Dissociative Adsorption on NiO(111): Energetics and Structure of Adsorbed Formate
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Zhao, Wei, Doyle, Andrew D., Morgan, Sawyer E., Bajdich, Michal, Nørskov, Jens K., and Campbell, Charles T.
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The dissociative adsorption of carboxylic acids on oxide surfaces is important for understanding adsorbed carboxylates, which are important as intermediates in catalytic reactions, for the organo-functionalization of oxide surfaces, and in many other aspects of oxide surface chemistry. We present here the first direct experimental measurement of the heat of dissociative adsorption of any carboxylic acid on any single-crystal oxide surface. The enthalpy of the dissociative adsorption of formic acid, the simplest carboxylic acid, to produce adsorbed formate and hydrogen (as a surface hydroxyl) on a (2 × 2)-NiO(111) surface is measured by single crystal adsorption calorimetry. The differential heat of adsorption decreases with formic acid coverage from 202 to 99 kJ/mol at saturation (0.25 ML). The structure of the adsorbed products is clarified by density functional theory (DFT) calculations, which provide energies in reasonable agreement with the calorimetry. These calculations show that formic acid readily dissociates on both the oxygen and Ni terminations of the octapolar NiO(111) surfaces, donating its acid H to a surface lattice oxygen, while HCOO adsorbs preferentially with bridging-type geometry near the M-O3/O-M3sites. The calculated energetics at low coverages agrees well with experimental data, while larger differences are observed at high coverage (0.25 ML). The large decrease in experimental heat of adsorption with coverage can be brought into agreement with the DFT energies if we assume that both types of octapolar surface terminations (O- and Ni-) are present on the starting surface.
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- 2024
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15. Ultrathin Cobalt Oxide Overlayer Promotes Catalytic Activity of Cobalt Nitride for the Oxygen Reduction Reaction
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Abroshan, Hadi, Bothra, Pallavi, Back, Seoin, Kulkarni, Ambarish, Nørskov, Jens K., and Siahrostami, Samira
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The oxygen reduction reaction (ORR) plays a crucial role in various energy devices such as proton-exchange membrane fuel cells (PEMFCs) and metal–air batteries. Owing to the scarcity of the current state-of-the-art Pt-based catalysts, cost-effective Pt-free materials such as transition metal nitrides and their derivatives have gained overwhelming interest as alternatives. In particular, cobalt nitride (CoN) has demonstrated a reasonably high ORR activity. However, the nature of its active phase still remains elusive. Here, we employ density functional theory calculations to study the surface reactivity of rocksalt (RS) and zincblend (ZB) cobalt nitride. The performances of the catalysts terminated by the facets of (100), (110), and (111) are studied for the ORR. We demonstrate that the cobalt nitride surface is highly susceptible to oxidation under ORR conditions. The as-formed oxide overlayer on the facets of CoNRS(100) and CoNZB(110) presents a significant promotional effect in reducing the ORR overpotential, thereby increasing the activity in comparison with those of the pure CoNs. The results of this work rationalize a number of experimental reports in the literature and disclose the nature of the active phase of cobalt nitrides for the ORR. Moreover, they offer guidelines for understanding the activity of other transition metal nitrides and designing efficient catalysts for future generation of PEMFCs.
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- 2024
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16. Theoretical Investigations of the Electrochemical Reduction of CO on Single Metal Atoms Embedded in Graphene
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Kirk, Charlotte, Chen, Leanne D., Siahrostami, Samira, Karamad, Mohammadreza, Bajdich, Michal, Voss, Johannes, Nørskov, Jens K., and Chan, Karen
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Single transition metal atoms embedded at single vacancies of graphene provide a unique paradigm for catalytic reactions. We present a density functional theory study of such systems for the electrochemical reduction of CO. Theoretical investigations of CO electrochemical reduction are particularly challenging in that electrochemical activation energies are a necessary descriptor of activity. We determined the electrochemical barriers for key proton–electron transfer steps using a state-of-the-art, fully explicit solvent model of the electrochemical interface. The accuracy of GGA-level functionals in describing these systems was also benchmarked against hybrid methods. We find the first proton transfer to form CHO from CO to be a critical step in C1product formation. On these single atom sites, the corresponding barrier scales more favorably with the CO binding energy than for 211 and 111 transition metal surfaces, in the direction of improved activity. Intermediates and transition states for the hydrogen evolution reaction were found to be less stable than those on transition metals, suggesting a higher selectivity for CO reduction. We present a rate volcano for the production of methane from CO. We identify promising candidates with high activity, stability, and selectivity for the reduction of CO. This work highlights the potential of these systems as improved electrocatalysts over pure transition metals for CO reduction.
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- 2024
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17. SBH10: A Benchmark Database of Barrier Heights on Transition Metal Surfaces
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Mallikarjun Sharada, Shaama, Bligaard, Thomas, Luntz, Alan C., Kroes, Geert-Jan, and Nørskov, Jens K.
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While the performance of density functional approximations (DFAs) for gas phase reaction energetics has been extensively benchmarked, their reliability for activation barriers on surfaces is not fully understood. The primary reason for this is the absence of well-defined, chemically accurate benchmark databases for chemistry on surfaces. We present a database of 10 surface barrier heights for dissociation of small molecules, SBH10, based on carefully chosen references from molecular beam scattering, laser assisted associative desorption, and thermal experiments. Our benchmarking study compares the performance of a dispersion-corrected generalized gradient approximation (GGA-vdW), BEEF-vdW, a meta-GGA, MS2, and a screened hybrid functional, HSE06. In stark contrast to gas phase reactions for which GGAs systematically underestimate barrier heights and hybrids tend to be most accurate, the BEEF-vdW functional determines barriers accurately to within 0.14 eV of experiments, while MS2 and HSE06 underestimate barrier heights on surfaces. Higher accuracy of BEEF-vdW stems from the fact that the functional is trained on chemisorption systems, and transition states for dissociation on surfaces closely resemble the final, chemisorbed states. Therefore, a functional that can describe chemisorption accurately can also reliably predict barrier heights on surfaces.
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- 2024
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18. Peripheral nerve blocks for closed reduction of distal radius fractures—A systematic review with meta‐analysis and trial sequential analysis.
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Pisljagic, Sanja, Temberg, Jens L., Steensbæk, Mathias T., Yousef, Sina, Maagaard, Mathias, Chafranska, Lana, Lange, Kai H. W., Rothe, Christian, Lundstrøm, Lars H., and Nørskov, Anders K.
- Subjects
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DISTAL radius fractures , *NERVE block , *PERIPHERAL nervous system , *SEQUENTIAL analysis , *PAIN management , *TRIALS (Law) - Abstract
Background Methods Results Conclusion Peripheral nerve blocks may provide better conditions for closed reduction of distal radius fractures as compared to other more frequently used modalities. In this systematic review, we evaluate existing evidence on the effect and harm of peripheral nerve blocks for closed reduction of distal radius fractures in adults.We performed a systematic review with meta‐analysis and trial sequential analysis including trials investigating the use of peripheral nerve blocks for closed reduction of distal radius fractures. Co‐primary outcomes were (1) the quality of the closed reduction measured as the proportion of participants needing surgery afterwards and (2) pain during closed reduction.Six trials (n = 312) met the inclusion criteria. One trial reported on the need for surgery with 4 of 25 participants receiving nerve block compared to 7 of 25 receiving haematoma block needing surgery (RR 0.57, 96.7% CI [0.19; 1.71], p = .50). Four trials reported pain during closed reduction. In a meta‐analysis, pain was not statistically significantly reduced with a nerve block (−2.1 Numeric Rating Scale (NRS) points (0–10), 96.7% CI [−4.4; 0.2], p = .07, tau2 = 5.4, I2 = 97%, TSA‐adj. 95% CI [−11.5; 7.3]). No trial sequential boundaries were crossed, and the required information size was not met. Pre‐planned subgroup analysis on trials evaluating ultrasound guided peripheral nerve blocks (patients = 110) showed a significant decrease in ‘pain during reduction’ (−4.1 NRS, 96.7% CI [−5.5; −2.6], p < .01, tau2 = 0.9, I2 = 80%). All trial results were at high risk of bias and the certainty of the evidence was very low.The certainty of evidence on the effect of peripheral nerve blocks for closed reduction of distal radius fractures is currently very low. Peripheral nerve blocks performed with ultrasound guidance may potentially reduce pain during closed reduction. High‐quality clinical trials are warranted. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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