14 research outputs found

    Development and Airworthiness Certification of the Ti6Al4V Inlet Casing Inner Forging

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    The inlet casing inner has manufactured using Ti-6Al-4V alloy through a closed die-forging route. It undergoes cyclic loads in addition to operating in extreme conditions in high-temperature environments. The demanding mission requirement of these engines necessitates the inlet casing inner to be flawless throughout its life cycle while retaining its structural integrity. It makes the qualification for airworthiness of the casing, a daunting task. In addition, the qualification tests also help to evaluate the design and manufacturing processes (closed die forging) of the inlet casing inner. The tests also provide data for further improvement of the inlet casing inner in terms of strength and fatigue life. It helps to ensure that the inlet casing inner will be able to perform as expected throughout its operational life. All the batch and consolidated test results comply with the relevant ASTM, MIL standards, and test schedule requirements

    Development and certification of chromic acid-free anodizing process for aircraft grade aluminium alloys

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    Chromic acid (Cr6+) anodization process is widely used for the corrosion protection of aircraft aluminium alloys. Hexavalent chromium being toxic in nature need to be phased out by eco-friendly alternatives. In the present study modified tartaric-sulphuric acid (TSA) process has been developed followed by sealing in permanganate based bath to obtain 4 to 6 µm thick anodic oxide layer on 2024-T3, 6061-T6 and 7075-T6 aluminium alloys. The process was carried out using a pilot scale anodizing plant. The anodized specimens were characterized for visual observation, thickness, adhesion, electrical breakdown voltage, corrosion resistance and tensile behaviour. All the tests were carried out as per MIL-A-8625F specifications. The specimens were also subjected for about 800 hrs to real time corrosion testing, 200 metres away from sea shore at Mandapam Camp, Rameshwaram, India. The performance of the permanganate sealed TSA anodized aluminium alloys are comparable with that of the conventional chromic acid anodized coatings. This chromic acid-free anodization process has been qualified to airworthiness regulating standards by Indian military certification authorities. Efforts are in progress to commercialize this technology for use on aero platforms

    Development and certification of chromic acid-free anodizing process for aircraft grade aluminium alloys

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    21-27Chromic acid (Cr6+) anodization process is widely used for the corrosion protection of aircraft aluminium alloys. Hexavalent chromium being toxic in nature need to be phased out by eco-friendly alternatives. In the present study modified tartaric-sulphuric acid (TSA) process has been developed followed by sealing in permanganate based bath to obtain 4 to 6 µm thick anodic oxide layer on 2024-T3, 6061-T6 and 7075-T6 aluminium alloys. The process was carried out using a pilot scale anodizing plant. The anodized specimens were characterized for visual observation, thickness, adhesion, electrical breakdown voltage, corrosion resistance and tensile behaviour. All the tests were carried out as per MIL-A-8625F specifications. The specimens were also subjected for about 800 hrs to real time corrosion testing, 200 metres away from sea shore at Mandapam Camp, Rameshwaram, India. The performance of the permanganate sealed TSA anodized aluminium alloys are comparable with that of the conventional chromic acid anodized coatings. This chromic acid-free anodization process has been qualified to airworthiness regulating standards by Indian military certification authorities. Efforts are in progress to commercialize this technology for use on aero platforms

    A conservation roadmap for the subterranean biome

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    The 15th UN Convention on Biological Diversity (CBD) (COP15) will be held in Kunming, China in October 2021. Historically, CBDs and other multilateral treaties have either alluded to or entirely overlooked the subterranean biome. A multilateral effort to robustly examine, monitor, and incorporate the subterranean biome into future conservation targets will enable the CBD to further improve the ecological effectiveness of protected areas by including groundwater resources, subterranean ecosystem services, and the profoundly endemic subsurface biodiversity. To this end, we proffer a conservation roadmap that embodies five conceptual areas: (1) science gaps and data management needs; (2) anthropogenic stressors; (3) socioeconomic analysis and conflict resolution; (4) environmental education; and (5) national policies and multilateral agreements.Peer reviewe

    Cohort Profile: Burden of Obstructive Lung Disease (BOLD) study

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    The Burden of Obstructive Lung Disease (BOLD) study was established to assess the prevalence of chronic airflow obstruction, a key characteristic of chronic obstructive pulmonary disease, and its risk factors in adults (≥40 years) from general populations across the world. The baseline study was conducted between 2003 and 2016, in 41 sites across Africa, Asia, Europe, North America, the Caribbean and Oceania, and collected high-quality pre- and post-bronchodilator spirometry from 28 828 participants. The follow-up study was conducted between 2019 and 2021, in 18 sites across Africa, Asia, Europe and the Caribbean. At baseline, there were in these sites 12 502 participants with high-quality spirometry. A total of 6452 were followed up, with 5936 completing the study core questionnaire. Of these, 4044 also provided high-quality pre- and post-bronchodilator spirometry. On both occasions, the core questionnaire covered information on respiratory symptoms, doctor diagnoses, health care use, medication use and ealth status, as well as potential risk factors. Information on occupation, environmental exposures and diet was also collected

    Synthesis and Characterization of Multifunctional Metal‐Organic Framework (Ni‐ZIF‐67) Decorated Waterborne Polyurethane (Ni‐ZIF‐67/WPU) Nanocomposites: Sonochemical Approach

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    Abstract This work investigates the effect of a modified nickel‐doped metal‐organic framework (Ni‐ZIF‐67) as a filler on thermal, mechanical, and water vapor permeability properties of environmentally friendly waterborne polyurethane (WPU). The facile and greener ultrasound (sonochemical) technique is developed to prepare multifunctional Ni‐ZIF‐67@WPU nanocomposites, exhibiting superior crystallinity and uniform distribution. The resultant Ni‐ZIF‐67 nanoparticles and Ni‐ZIF‐67@WPU films are characterized by various techniques, including powder XRD, FE‐SEM, FTIR, TGA, UTM, contact angle, and antibacterial properties. Ni‐ZIF‐67@WPU nanocomposites exhibited excellent three‐fold mechanical performance (tensile strength ≈22 MPa) at a very low 5 wt.% filler loading and high thermal stability compared to pristine WPU. In addition, Ni‐ZIF‐67@WPU exhibited optimum water vapor permeability performance at 5.0 wt.% filler with the potential antibacterial application. Demonstrate that the rapid and facile synthesis approach can enhance the interaction of filler and matrix, high surface area, and tuneable pore size of filler material. This new insight has a new green approach for fabricating advanced nanocomposites toward practical utilization

    Recent Progress in Intensifying Synthesis of Acrylic Microspheres for Catalysis

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    Abstract Over the past decades, there has been an escalating rise in the need for chemicals and catalytic materials to keep up with global demands. Addressing those issues by conventional methods often becomes inefficient, with myriad operational risks. Process intensification methods through procedural and equipment‐based modifications have been considered greener, have higher heat and mass transfer rates, and operate with lower costs. In this review, research using ultrasonic reactors and microreactors, along with developments through an integrated external energy source, for synthesizing acrylic microspheres is covered extensively. Acrylic microspheres have garnered much interest for their biocompatibility, affinity toward functionalization, and wide range of applications. Core–shell, composite, functional‐group modified, and porous acrylic microspheres are used for enzyme immobilization and as catalyst carriers. The use of acrylic support has provided huge improvements in catalytic activity, reusability, recyclability, and overall stability. Finally, various other process intensification methods and alternate support materials are covered to help enhance future developments in the field of catalysis

    New vegetation type map of India prepared using satellite remote sensing: Comparison with global vegetation maps and utilities

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    International audienceA seamless vegetation type map of India (scale 1: 50,000) prepared using medium-resolution IRS LISS-III images is presented. The map was created using an on-screen visual interpretation technique and has an accuracy of 90%, as assessed using 15,565 ground control points. India has hitherto been using potential vegetation/forest type map prepared by Champion and Seth in 1968. We characterized and mapped further the vegetation type distribution in the country in terms of occurrence and distribution, area occupancy, percentage of protected area (PA) covered by each vegetation type, range of elevation, mean annual temperature and precipitation over the past 100 years. A remote sensing-amenable hierarchical classification scheme that accommodates natural and semi-natural systems was conceptualized, and the natural vegetation was classified into forests, scrub/shrub lands and grasslands on the basis of extent of vegetation cover. We discuss the distribution and potential utility of the vegetation type map in a broad range of ecological, climatic and conservation applications from global, national and local perspectives. We used 15,565 ground control points to assess the accuracy of products available globally (i.e., GlobCover, Holdridge’s life zone map and potential natural vegetation (PNV) maps). Hence we recommend that the map prepared herein be used widely. This vegetation type map is the most comprehensive one developed for India so far. It was prepared using 23.5 m seasonal satellite remote sensing data, field samples and information relating to the biogeography, climate and soil. The digital map is now available through a web portal (http://bis.iirs.gov.in)
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