Synthesis and optimisation of IrO2 electrocatalysts by Adams fusion method for solid polymer electrolyte electrolysers

IrO2 as an anodic electrocatalyst for the oxygen evolution reaction (OER) in solid polymer electrolyte (SPE) electrolysers was synthesised by adapting the Adams fusion method. Optimisation of the IrO2 electrocatalyst was achieved by varying the synthesis duration (0.5 – 4 hours) and temperature (250 - 500°C). The physical properties of the electrocatalysts were characterised by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction (XRD). Electrochemical characterisation of the electrocatalysts toward the OER was evaluated by chronoamperometry (CA). CA analysis revealed the best electrocatalytic activity towards the OER for IrO2 synthesised for 2 hours at 350oC which displayed a better electrocatalytic activity than the commercial IrO2 electrocatalyst used in this study. XRD and TEM analyses revealed an increase in crystallinity and average particle size with increasing synthesis duration and temperature which accounted for the decreasing electrocatalytic activity. At 250°C the formation of an active IrO2 electrocatalyst was not favoured

FORMULATION AND EVALUATION OF MICROEMULSION GEL FOR TRANSDERMAL DELIVERY OF TRAMADOL

Objective: The present work was carried out to design microemulsion gel system for transdermal delivery of the drug to minimize the side effects and to reduce the frequency of administration and for prolonging the duration of action. Methods: Tramadol, an opioid analgesic drug, was mixed with various selected polymers such as sodium alginate (SA), acacia, hydroxypropyl methylcellulose (HPMC), and Eudragit in geometric mixing ratios. The drug, polymer, and other excipients were mixed thoroughly by trituration method and different formulations (F1-F8) were prepared the same quantity of all the ingredients excepting the polymers. Results: The different formulations prepared, studied, and showed that the formulation using SA as polymeric carrier had a better effect on the evaluated parameters. The drug-SA formulation exhibited better drug-polymer compatibility, optimal viscosity (2750 cps), zeta potential (−26.1 Mv), and particle size distribution (262.8 d.nm) values. The in vitro release studies also indicated that the drug-SA formulation was of desirable release pattern, thus indicating that SA to be a better choice in formulating a transdermal delivery gel system. Conclusion: Evaluated microemulsion gel formulation F2 of tramadol with polymeric carriers SA was much stable than other carriers used. Thus, it could be concluded that the gel formulation with SA can be taken as an ideal formulation

Performance and Structure of LiNi0.5Mn1.5O4 Prepared from Various Ni Precursors for Lithium Ion Batteries

LiNi0.5Mn1.5O4 compounds were prepared through a solid-state reaction using various Ni precursors. The effect of the precursors on the electrochemical performance of LiNi0.5Mn1.5O4 was investigated. LiNi0.5Mn1.5O4 made from Ni(NO3)2•6H2O shows the best charge-discharge performance. The reversible capacity of LiNi0.5Mn1.5O4 is about 145mAh g–1 and remained at 143mAh g–1 after 10 cycles at 3.0 to 5.0 V. The XRD results showed that the precursors and dispersion method had significant effects on their structures. Pure spinel phase can be obtained with a high energy ball-milling method and Ni(NO3)2•6H2O as precursor. A trace amount of the NiO phase was detected in LiNi0.5Mn1.5O4 with the manual grinding method when Ni(CH3COO)2•6H2O, NiO and Ni2O3 were used as precursors.Keywords: LiNi0.5Mn1.5O

The impact of positive psychological interventions on well-being in healthy elderly people

This systematic review aims to evaluate the impact of Positive Psychological Interventions (PPIs) on well-being in healthy older adults. Systematic review of PPIs obtained from three electronic databases (PsycINFO, Scopus, and Web of Science) was undertaken. Inclusion criteria were: that they were positive psychology intervention, included measurement of well-being, participants were aged over 60 years, and the studies were in English. The Cochrane Collaboration Guidelines dimensions of quality control, randomization, comparability, follow-up rate, dropout, blinding assessors are used to rate the quality of studies by two reviewers independently. The RE-AIM (Reach, Efficacy, Adoption, Implementation, and Maintenance) for evaluation of PPIs effectiveness was also applied. The final review included eight articles, each describing a positive psychological intervention study. The reminiscence interventions were the most prevalent type of PPIs to promote and maintain well-being in later life. Only two studies were rated as high quality, four were of moderate-quality and two were of low-quality. Overall results indicated that efficacy criteria (89%), reach criteria (85%), adoption criteria (73%), implementation criteria (67%), and maintenance criteria (4%) across a variety of RE-AIM dimensions. Directions for future positive psychological research related to RE-AIM, and implications for decision-making, are described

Metal hydride hydrogen storage and compression systems for energy storage technologies

Along with a brief overview of literature data on energy storage technologies utilising hydrogen and metal hydrides, this article presents results of the related R&D activities carried out by the authors. The focus is put on proper selection of metal hydride materials on the basis of AB5- and AB2-type intermetallic compounds for hydrogen storage and compression applications, based on the analysis of PCT properties of the materials in systems with H2 gas. The article also presents features of integrated energy storage systems utilising metal hydride hydrogen storage and compression, as well as their metal hydride based components developed at IPCP and HySA Systems

Waste Package Neutron Absorber, Thermal Shunt, and Fill Gas Selection Report

Materials for neutron absorber, thermal shunt, and fill gas for use in the waste package were selected using a qualitative approach. For each component, selection criteria were identified; candidate materials were selected; and candidates were evaluated against these criteria. The neutron absorber materials evaluated were essentially boron-containing stainless steels. Two candidates were evaluated for the thermal shunt material. The fill gas candidates were common gases such as helium, argon, nitrogen, carbon dioxide, and dry air. Based on the performance of each candidate against the criteria, the following selections were made: Neutron absorber--Neutronit A978; Thermal shunt--Aluminum 6061 or 6063; and Fill gas--Helium

Investigation of water-logged spent fuel rods under dry storage conditions

Tests were conducted to determine the amount of moisture contained in breached, water-logged spent fuel rods and the rate of release. Two well-characterized BWR fuel rods with reactor-induced breaches were tested in a hot cell. These rods contained approximately 6 to 10 g of moisture, most of which was released during heating tests simulating normal cask drying operations. Additional testing with two intentionally defected fuel rods (BWR and PWR) was performed to evaluate the effect of the cladding breach on migration of moisture along the length of the fuel rod. The results showed that the moisture released from reactor-breached spent fuel rods was insufficient to cause degradation of fuel or dry storage system components

Waste Package and Material Testing for the Proposed Yucca Mountain High Level Waste Repository

Over the repository lifetime, the waste package containment barriers will perform various functions that will change with time. During the operational period, the barriers will function as vessels for handling, emplacement, and waste retrieval (if necessary). During the years following repository closure, the containment barriers will be relied upon to provide substantially complete containment, through 10,000 years and beyond. Following the substantially complete containment phase, the barriers and the waste package internal structures help minimize release of radionuclides by aqueous- and gaseous-phase transport. These requirements have lead to a defense-in-depth design philosophy. A multi-barrier design will result in a lower breach rate distributed over a longer period of time, thereby ensuring the regulatory requirements are met. The design of the Engineered Barrier System (EBS) has evolved. The initial waste package design was a thin walled package, 3/8 inch of stainless steel 304, that had very limited capacity, (3 PWR and 4 BWR assemblies) and performance characteristics, 300 to 1,000 years. This design required over 35,000 waste packages compared to today's design of just over 10,000 waste packages. The waste package designs are now based on a defense-in-depth/multi-barrier philosophy and have a capacity similar to the standard storage and rail transported spent nuclear fuel casks. Concurrent with the development of the design of the waste packages, a comprehensive waste package materials testing program has been undertaken to support the selection of containment barrier materials and to develop predictive models for the long-term behavior of these materials under expected repository conditions. The testing program includes both long-term and short-term tests and the results from these tests combination with the data published in the open literature are being used to develop models for predicting performance of the waste packages

Investigation of stainless steel clad fuel rod failures and fuel performance in the Connecticut Yankee Reactor. Final report

Significant levels of fuel rod failures were observed in the batch 8 fuel assemblies of the Connecticut Yankee reactor. Failure of 304 stainless steel cladding in a PWR environment was not expected. Therefore a detailed poolside and hot cell examination program was conducted to determine the cause of failure and identify differences between batch 8 fuel and previous batches which had operated without failures. Hot cell work conducted consisted of detailed nondestructive and destructive examination of fuel rods from batches 7 and 8. The results indicate that the batch 8 failure mechanism was stress corrosion cracking initiating on the clad outer surface. The sources of cladding stresses are believed to be (a) fuel pellet chips wedged in the cladding gap, (b) swelling of highly nondensifying batch 8 fuel and (c) potentially harmful effects of a power change event that occurred near the end of the second cycle of irradiation for batch 8