Core/shell structure nano-iron/iron carbide electrodes for rechargeable alkaline iron batteries

In this work, we have studied a 2% copper substituted core shell type iron/iron carbide as a negative electrode for application in energy storage. The NanoFe-Fe3C-Cu delivered 367 mAh g−1 at ≈80% current efficiency, successfully running for over 300 cycles. The superior electrode kinetics and performance were assessed by rate capability, galvanostatic, potentiodynamic polarization measurements in 6 M KOH electrolyte and at ambient temperature. Ex-situ XRD characterizations and SEM images of both the fresh and used electrode surfaces show that nanoparticles were found to be still intact with negligible particle agglomeration. The electrodes have shown stable performances with low capacity decay, whereas sulfur dissolution from the additive Bi2S3 was found to decrease the charging efficiency with time. This core-shell type structured nano material is, consequently, an auspicious anode candidate in alkaline-metal/air and Ni-Fe battery systems.QC 20170627</p

28π Non‐Fused Hexaphyrin: Synthesis, Protonation Triggered Möbius Aromaticity and Structural Properties

International audienceSynthesis of core‐modified 28π non‐fused hexaphyrin is reported. The optical and 1H NMR spectral analysis reveals the non‐aromatic nature macrocycle in its freebase form at 298K. However, upon lowering temperature to 193K a partial aromaticity was observed experiment. structural elucidations for also justify non‐aromaticity hexaphyrin, where thiophene units 1,2 diphenyl dithienyl ethene moiety deviated maximum from overall macrocyclic framework. Protonation on imino pyrrolic nitrogens results single crystal X‐ray structures which shows an essential distortion framework needed effective π‐electron delocalization, attaining Möbius aromaticity. Nucleus Independent Chemical Shift (NICS) values protonated macrocycles are ‐2.0 ppm ‐5.6 ppm. Anisotropy Induced Current density clockwise delocalization current vectors. Overall, spectral, theoretical suggests nonaromatic aromatic hexaphyrin

Synthesis and Workability Behavior of Cu-X wt.% TiC (x = 0, 4, 8, and 12) Powder Metallurgy Composites

In this work, copper (Cu) matrix composite reinforced with titanium carbide (TiC) was fabricated by powder metallurgy (PM) method with the varying TiC content from 0% to 12% by weight in the step of 4%. The required weight percentage of powders was milled in an indigenously developed ball milling setup. Green compacts were made using a computer-controlled hydraulic press (400 kN) and sintered in a muffle furnace at a temperature of 950°C. Scanning electron microscope (SEM) was used to analyze the distribution of TiC particles in Cu matrix in as-sintered conditions. X-ray diffraction (XRD) analysis resulted in the existence of respective phases in the produced composites. The structural characteristics such as stress, strain, dislocation density, and grain size of the milled composites were evaluated. Cold upsetting was conducted for the sintered composites at room temperature to evaluate the axial (σz), hoop (σө), hydrostatic (σm), and effective (σeff) true stresses. These stresses were analyzed against true axial strain (εz). Results showed that the increase in the inclusion of weight percentage of TiC into the Cu matrix increases density, hardness, (σz), (σө), (σm), (σeff), and stress ratio parameters such as (σz/σeff), (σθ/σeff), (σm/σeff), and (σz/σθ) of the composites

Synthesis and Workability Behavior of Cu-X wt.% TiC (x = 0, 4, 8, and 12) Powder Metallurgy Composites

In this work, copper (Cu) matrix composite reinforced with titanium carbide (TiC) was fabricated by powder metallurgy (PM) method with the varying TiC content from 0% to 12% by weight in the step of 4%. The required weight percentage of powders was milled in an indigenously developed ball milling setup. Green compacts were made using a computer-controlled hydraulic press (400 kN) and sintered in a muffle furnace at a temperature of 950°C. Scanning electron microscope (SEM) was used to analyze the distribution of TiC particles in Cu matrix in as-sintered conditions. X-ray diffraction (XRD) analysis resulted in the existence of respective phases in the produced composites. The structural characteristics such as stress, strain, dislocation density, and grain size of the milled composites were evaluated. Cold upsetting was conducted for the sintered composites at room temperature to evaluate the axial (σz), hoop (σө), hydrostatic (σm), and effective (σeff) true stresses. These stresses were analyzed against true axial strain (εz). Results showed that the increase in the inclusion of weight percentage of TiC into the Cu matrix increases density, hardness, (σz), (σө), (σm), (σeff), and stress ratio parameters such as (σz/σeff), (σθ/σeff), (σm/σeff), and (σz/σθ) of the composites.</jats:p

Performance Evaluation of Exotic Coconut Genotypes to Assess their Suitability for Cultivation in the Western Zone of Tamil Nadu

Identification and utilization potential genotypes for development of high yielding cultivars with distinctive traits is the need of the hour to cope up with the shifting demand of international market. The present research examination was carried among seven exotic coconut genotypes viz., San Ramon Tall (SNRT), Federated Malay States Tall (FMST), British Solomon Island Tall (BSIT), Zanzibar Tall (ZNT), St. Vincent Tall (STVT), Gonthembili Tall (GTBT) and Java Tall (JVT) in comparison with three indigenous coconut ecotypes viz., Tiptur Tall (TPT), East Coast Tall (ECT), and Arasampatti Tall (APT) at ICAR-AICRP (Palms) centre, Coconut Research Station, Aliyarnagar. The investigation was intended to identify suitable exotic coconut genotypes with increased copra quantity and quality along with good tender nut parameters for cultivation in the Western Zone of Tamil Nadu. Based on the observations recorded over a period of eight years from 2010 to 2017, Federated Malay States recorded maximum girth (121.2cm) while San Ramon Tall was found to be superior in terms of floral traits and inflorescence production per year. Java tall produced maximum number of buttons per inflorescence (26.0)among the genotypes evaluated. The highest annual nut yield was recorded by Zanzibar Tall (106.6 nuts per palm per year)followed by Federated Malay States (99.9 nuts per palm per year), while San Ramon Tall also recorded considerable nut yield of 75.3 nuts per palm per year. Sanramon Tall recorded the highest average copra content (333.2 gram per nut) with an estimated copra yield of 25.1 Kg per palm per year. Taking into consideration of yield attributes, fruit component traits and tender nut quality parameters, the exotic genotypes San Ramon Tall (SNRT) and Federated Malay States Tall (FMST) were found to be suitable for cultivation in the Western zones of Tamil Nadu.</jats:p