Double Layer at the Pt(111)-Aqueous Electrolyte Interface: Potential of Zero Charge and Anomalous Gouy-Chapman Screening

We report, for the first time, the observation of a Gouy–Chapman capacitance minimum at the potential of zero charge of the Pt(111)‐aqueous perchlorate electrolyte interface. The potential of zero charge of 0.3 V vs. NHE agrees very well with earlier values obtained by different methods. The observation of the potential of zero charge of this interface requires a specific pH (pH 4) and anomalously low electrolyte concentrations (−3 m). By comparison to gold and mercury double‐layer data, we conclude that the diffuse double layer structure at the Pt(111)‐electrolyte interface deviates significantly from the Gouy–Chapman theory in the sense that the electrostatic screening is much better than predicted by purely electrostatic mean‐field Poisson–Boltzmann theory.Catalysis and Surface Chemistr

Double Layer at the Pt(111)–Aqueous Electrolyte Interface: Potential of Zero Charge and Anomalous Gouy–Chapman Screening

We report, for the first time, the observation of a Gouy–Chapman capacitance minimum at the potential of zero charge of the Pt(111)‐aqueous perchlorate electrolyte interface. The potential of zero charge of 0.3 V vs. NHE agrees very well with earlier values obtained by different methods. The observation of the potential of zero charge of this interface requires a specific pH (pH 4) and anomalously low electrolyte concentrations (−3 m). By comparison to gold and mercury double‐layer data, we conclude that the diffuse double layer structure at the Pt(111)‐electrolyte interface deviates significantly from the Gouy–Chapman theory in the sense that the electrostatic screening is much better than predicted by purely electrostatic mean‐field Poisson–Boltzmann theory.Catalysis and Surface Chemistr

Green synthesis of silver nanoparticles using Piper longum catkin extract irradiated by sunlight: antibacterial and catalytic activity

In this study, rapid and cost-effective biosynthesis of silver nanoparticles (AgNPs) was synthesized by using Piper longum (P. longum) catkin extract. The bioreduction of AgNPs was initially confirmed by using UV–visible spectroscopy which exhibits characteristic absorption peak at 450\ua0nm in 120\ua0s when exposed to sunlight. The phytoconstituents responsible for the reduction of AgNO to Ag NPs were examined using Fourier transform infrared spectroscopy. The crystalline nature of Ag NPs was confirmed using the X-ray diffraction pattern. Morphological studies confirmed the synthesized Ag NPs were monodispersed and spherical in shape with the size ranging from 15 to 40\ua0nm. The zeta potential analysis of the synthesized AgNPs exhibit negative value (− 24.3\ua0mV), which indicates higher stability. Further, the proficiency of the synthesized AgNPs was evaluated against mastitis-causing bacteria. Hence, the Ag NPs showed the maximum zone of inhibition against Staphylococcus aureus (12.45\ua0mm), Pseudomonas aeruginosa (12.34\ua0mm), and Bacillus subtilis (9.75\ua0mm). In addition, the catalytic efficiency of Ag NPs was investigated for the conversion of methyl orange to hydrazine derivatives, methylene blue to leuco methylene blue, and o-nitrophenol to o-aminophenol in 4, 5 and 3\ua0min, respectively. Hence, this study explores the doctrine of green chemistry for the rapid production of AgNPs that act as a potential candidate to alleviate mastitis-causing bacteria and clear up diverse environmental problems

<span style="font-size:14.0pt;line-height: 115%;font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; color:black;mso-ansi-language:EN-IN;mso-fareast-language:EN-IN;mso-bidi-language: HI" lang="EN-IN">5-HT₃receptors in selective animal models of cognition</span>

174-180<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Role of 5-HT3 receptors in cholinergic hypofunctional models of cognitive impairment in the elevated plus maze model and a passive avoidance model is studied. Cognitive impairment was caused by scopolamine (1 mg/kg, ip) in mice and 5-HT3 ligands mCPBG (1 and 5 mg/kg, ip) and ondansetron (0.5 and 5mg/kg, ip) were administered before the pre- learning phase to study the effects on acquisition, while post-learning administration was used to determine the effects on consolidation. Ondansetron improved acquisition and retention in cholinergic hypofunctional models while mCPBG potentiated selected impaired cognitive indices. The results indicate the role of 5-HT3 receptors in cognition and that an ideal evaluation of 5-HT3 ligands in cognition should distinguish true cognitive effects from locomotor, motivational and emotional effects<span style="font-size: 8.0pt;line-height:115%;font-family:" times="" new="" roman";mso-fareast-font-family:="" "times="" roman";color:black;mso-ansi-language:en-in;mso-fareast-language:="" en-in;mso-bidi-language:hi"="" lang="EN-IN">.</span