Influence of Cations on HCOOH and CO Formation during CO2 Reduction on a PdMLPt(111) Electrode

Understanding the role of cations in the electrochemical CO2 reduction (CO2RR) process is of fundamental importance for practical application. In this work, we investigate how cations influence HCOOH and CO formation on PdMLPt(111) in pH 3 electrolytes. While only (a small amount of adsorbed) CO forms on PdMLPt(111) in the absence of metal cations, the onset potential of HCOOH and CO decreases with increasing cation concentrations. The cation effect is stronger on HCOOH formation than that on CO formation on PdMLPt(111). Density functional theory simulations indicate that cations facilitate both hydride formation and CO2 activation by polarizing the electronic density at the surface and stabilizing *CO2-. Although the upshift of the metal work function caused by high coverage of adsorbates limits hydride formation, the cation-induced electric field counterbalances this effect in the case of *H species, sustaining HCOOH production at mild negative potentials. Instead, at the high *CO coverages observed at very negative potentials, surface hydrides do not form, preventing the HCOOH route both in the absence and presence of cations. Our results open the way for a consistent evaluation of cationic electrolyte effects on both activity and selectivity in CO2RR on Pd-Pt catalysts

A comparison of the time course of action and laryngeal mask airway insertion conditions with different doses of mivacurium for day-case urologic surgery in children: a prospective cohort study

ObjectiveTo investigate the time course of action of different doses of mivacurium and determine the appropriate dose for laryngeal mask airway (LMA) insertion for day-case urologic surgery in children.MethodsA total of 105 patients who enrolled in this study between March 2021 and December 2021 were randomised into 3 groups: Group A (mivacurium 0.15 mg/kg, n = 35), Group B (mivacurium 0.20 mg/kg, n = 35) and Group C (mivacurium 0.25 mg/kg, n = 35). The different doses of mivacurium were injected before LMA insertion. The primary outcomes included the grading of conditions for the LMA insertion-18 score, onset time, recovery index and the duration that mivacurium was effective. Secondary outcomes included pulse oxygen saturation, mean blood pressure, heart rate and the incidence of adverse events.ResultsThe score of the conditions for LMA insertion in Group A was significantly lower than in Groups C and B (p < 0.005). There was a significant difference in the onset time between Groups B and A (p < 0.005). There was no significant difference in the overall incidence of adverse reactions between these groups (p > 0.05).ConclusionAnaesthesia with 0.2 mg/kg of mivacurium can effectively shorten the onset time and facilitate insertion of the LMA in children undergoing day-case urologic surgery

Retraction Note: Effect of perioperative infusion of Dexmedetomidine combined with Sufentanil on quality of postoperative analgesia in patients undergoing laparoscopic nephrectomy: a CONSORT-prospective, randomized, controlled trial

The authors have retracted this articl

RETRACTED ARTICLE: Effect of perioperative infusion of Dexmedetomidine combined with Sufentanil on quality of postoperative analgesia in patients undergoing laparoscopic nephrectomy: a CONSORT-prospective, randomized, controlled trial

Abstract Background Postoperative pain is one of the most common symptoms after surgery, which brings physical discomfort to patients. In addition, it may cause a series of complications, and even affect the long-term quality of life. The purpose of this prospective, randomized, double-blinded, controlled trial is to investigate the efficacy and safety of dexmedetomidine combined with sufentanil to attenuate postoperative pain in patients after laparoscopic nephrectomy. Methods Ninety patients undergoing laparoscopic nephrectomy were randomized into three groups: the control (sufentanil 0.02 μg/kg/h, Group C), sufentanil plus low dose of dexmedetomidine (0.02 μg/kg/h each, Group D1), and sufentanil plus high dose of dexmedetomidine (0.04 μg/kg/h, Group D2). The patient-controlled analgesia was programmed to deliver a bolus dose of 0.5 ml, followed by an infusion of 2 ml/h and a lockout time of 10 min. The primary goal was to calculate the cumulative amount of self-administered sufentanil; the secondary goals were to estimate pain intensity using the numerical rating scale (NRS), level of sedation, the first bowel movement, concerning adverse effects as well as duration of postoperative hospital stay. Results The total consumption of sufentanil in group D1 and D2 were significantly lower than in group C during the first 8 h after surgery (P  0.05) between group D1 and D2. Compared with group C, the NRS scores at rest during first 8 h after surgery were significantly lower in group D1 (P  0.05). The time to first flatus was shorter in group D1 compared with the control group (P < 0.05). In addition, compared with group C, group D1 and D2 had a shorter time for first defecation (P < 0.05). Conclusions Dexmedetomidine combined with sufentanil showed better postoperative analgesia without adverse effects, as well as facilitated bowel movements for patients undergoing laparoscopic nephrectomy. Trial registration We registered this study in a Chinese Clinical Trial Registry (ChiCTR) centre on Dec 23 2015 and received the registration number: ChiCTR-IPR-15007628

Emergence of Potential-Controlled Cu-Nanocuboids and Graphene-Covered Cu-Nanocuboids under Operando CO2Electroreduction

The electroreduction of CO2 (CO2RR) is a promising strategy toward sustainable fuels. Cu is the only Earth-abundant and pure metal capable of catalyzing CO2-to-hydrocarbons conversion with significant Faradaic efficiencies; yet, its dynamic structure under operando CO2RR conditions remains unknown. Here, we track the Cu structure operando by electrochemical scanning tunneling microscopy and Raman spectroscopy. Surprisingly, polycrystalline Cu surfaces reconstruct forming Cu nanocuboids whose size can be controlled by the polarization potential and the time employed in their in situ synthesis, without the assistance of organic surfactants and/or halide anions. If the Cu surface is covered by a graphene monolayer, smaller features with enhanced catalytic activity for CO2RR can be prepared. The graphene-protecting layer softens the 3D morphological changes that Cu-based catalysts suffer when exposed to aggressive electrochemical environments and allows us to track the kinetic roughening process. This novel strategy is promising for improving Cu long-term stability, and consequently, it could be used as a platform to ultimately control product selectivity.Fil: Phan, Thanh Hai. École Polytechnique Fédérale de Lausanne; SuizaFil: Banjac, Karla. École Polytechnique Fédérale de Lausanne; SuizaFil: Cometto, Fernando Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. École Polytechnique Fédérale de Lausanne; SuizaFil: Dattila, Federico. Barcelona Institute Of Science And Technology; EspañaFil: García Muelas, Rodrigo. Barcelona Institute Of Science And Technology; EspañaFil: Raaijman, Stefan J.. Leiden University; Países BajosFil: Ye, Chunmiao. Leiden University; Países BajosFil: Koper, Marc T. M.. Leiden University; Países BajosFil: López, Núria. Barcelona Institute Of Science And Technology; EspañaFil: Lingenfelder, Magalí Alejandra. École Polytechnique Fédérale de Lausanne; Suiz