13 research outputs found

    Studies of Process Parameters on Scale up of Nd:YAG Nanopowder Synthesis by Sol-gel Process

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    Scale up of process from 6 g to 200 g batch for preparation of phase pure Neodymium doped Yttrium Aluminum Garnet (Nd:YAG) nanopowder by sol-gel process using nitrate-citrate route was carried out. Optimisation of process parameters was done to resolve problems associated with large batch such as evolution of large amount of acidic fumes, increased gelation and drying time and incomplete calcination. The problem of exhaust of excess acidic fumes with size scale up was handled by passing ammonia and optimized pH of the sol. Process of drying the sol was optimised for large batch size. On scaling up from 6 g to 200 g batch incomplete crystallization was observed  on calcination under conditions optimized for 6 g batch. The causes of incomplete calcination with size scale up was identified and resolved to achieve completely crystalline particles in the range of ~25 nm to 50 nm.Defence Science Journal, 2012, 62(1), pp.199-202, DOI:http://dx.doi.org/10.14429/dsj.62.83

    Nd:GGG Nanopowders by Microwave Gel Combustion Route and Sinterability Studies

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    Synthesis of Nd0.03Gd2.97Ga5O12 (Nd:GGG) nanopowder was carried out by microwave-assisted nitrate-citrate gel combustion technique. Various nitrate-to-citrate ratios from stoichiometric-to-fuel lean were explored. Gels were combusted by microwave heating and the combusted powders were calcined at 900 OC for 2 h. Fourier Transform Infra-red Spectroscopy (FTIR) and X-ray Diffraction (XRD) of calcined nanopowders showed phase pure Nd:GGG formation, from stoichiometric-to-fuel lean nitrate-to-citrate ratio of 1 to 0.416. Particles in the size range of 150 nm - 200 nm were obtained for stoichiometric ratio. Highly uniform, spherical morphology, with size range 90 nm - 100 nm, were obtained in fuel lean ratio of 1 to 0.416. Sintering of these nanopowders at 1550 °C for 2 h in air resulted in retention of phase purity as observed by XRD. Grain growth of less than 2 μm, for fuel lean ratio of 1 to 0.416, indicated formation of highly sinterable Nd:GGG nanopowders.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.490-494, DOI:http://dx.doi.org/10.14429/dsj.64.540

    Establishing a core outcome set for peritoneal dialysis : report of the SONG-PD (standardized outcomes in nephrology-peritoneal dialysis) consensus workshop

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    Outcomes reported in randomized controlled trials in peritoneal dialysis (PD) are diverse, are measured inconsistently, and may not be important to patients, families, and clinicians. The Standardized Outcomes in Nephrology-Peritoneal Dialysis (SONG-PD) initiative aims to establish a core outcome set for trials in PD based on the shared priorities of all stakeholders. We convened an international SONG-PD stakeholder consensus workshop in May 2018 in Vancouver, Canada. Nineteen patients/caregivers and 51 health professionals attended. Participants discussed core outcome domains and implementation in trials in PD. Four themes relating to the formation of core outcome domains were identified: life participation as a main goal of PD, impact of fatigue, empowerment for preparation and planning, and separation of contributing factors from core factors. Considerations for implementation were identified: standardizing patient-reported outcomes, requiring a validated and feasible measure, simplicity of binary outcomes, responsiveness to interventions, and using positive terminology. All stakeholders supported inclusion of PD-related infection, cardiovascular disease, mortality, technique survival, and life participation as the core outcome domains for PD

    Electroreduction of oxygen on some novel cobalt phthalocyanine complexes

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    The catalytic activity of cobalt phthalocyanine monomer and some of its polymeric derivatives towards the electroreduction of molecular oxygen in salt and alkaline solutions is examined. It is found that most of these complexes exhibit a higher catalytic activity than the cobalt phthalocyanine monomer

    Mannosomes: a molluscan intracellular tubular membrane system related to heavy metal stress?

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    Metadadata onlyAmongst animals, several hydrogen peroxide-generating oxidases are apparently restricted to molluscs. One of these, -mannitol oxidase, is concentrated in the alimentary system, where it is associated with its own subcellular membrane system of unique tubular morphology, most likely representing a structural modification of the ER. These structures can be purified by subcellular fractionation and have been termed ‘mannosomes’. Little is known about the functions of mannitol oxidase or of mannosomes, but the previously reported molluscicide-induced increase in mannosomes implies their involvement in a general stress reaction. In this study, we examined the effects of heavy metal stress in the terrestrial gastropod Arion lusitanicus. The activity of mannitol oxidase and mannosome abundance were monitored, together with metal effects on heat-shock protein level, and these parameters were compared to heavy metal accumulation in the digestive gland. We found that mannitol oxidase is inhibited by heavy metals more than other oxidases. On the other hand, hsp70 levels and mannosomal protein were increased with enhanced heavy metal stress, the latter indicating a probable increase in the number of mannosome organelles. Thus, stress protein (hsp70) and mannosomal protein were positively correlated with heavy metal accumulation, whereas the enzyme activity showed a negative correlation with increasing heavy metal content of the slugs

    Molecular Profiles of Amyloid-β Proteoforms in Typical and Rapidly Progressive Alzheimer’s Disease

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    The molecular determinants of atypical clinical variants of Alzheimer's disease, including the recently discovered rapidly progressive Alzheimer's disease (rpAD), are unknown to date. Fibrilization of the amyloid-β (Aβ) peptide is the most frequently studied candidate in this context. The Aβ peptide can exist as multiple proteoforms that vary in their post-translational processing, amyloidogenesis, and toxicity. The current study was designed to identify these variations in Alzheimer's disease patients exhibiting classical (sAD) and rapid progression, with the primary aim of establishing if these variants may constitute strains that underlie the phenotypic variability of Alzheimer's disease. We employed two-dimensional polyacrylamide gel electrophoresis and MALDI-ToF mass spectrometry to validate and identify the Aβ proteoforms extracted from targeted brain tissues. The biophysical analysis was conducted using RT-QuIC assay, confocal microscopy, and atomic force microscopy. Interactome analysis was performed by co-immunoprecipitation. We present a signature of 33 distinct pathophysiological proteoforms, including the commonly targeted A

    Results of the 2021 ECFA Early-Career Researcher Survey on Training in Instrumentation

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    The European Committee for Future Accelerators (ECFA) Early-Career Researchers (ECR) Panel was invited by the ECFA Detector R&D Roadmap conveners to collect feedback from the European ECR community. A working group within the ECFA ECR panel held a Townhall Meeting to get first input, and then designed and broadly circulated a detailed survey to gather feedback from the larger ECR community. A total of 473 responses to this survey were received, providing a useful overview of the experiences of ECRs in instrumentation training and related topics. This report summarises the feedback received, and is intended to serve as an input to the ECFA Detector R&D Roadmap process
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