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Recent Advancements in the Development of Sensors for the Structural Health Monitoring (SHM) at High-Temperature Environment: A Review
No full textWith Industry 4.0 becoming increasingly pervasive, the importance and usage of sensors has increased several folds. Industry 4.0 refers to a new phase in the industrial revolution that mainly focuses on inter-connectivity, automation, machine learning, and real-time data. Real-time structural health monitoring (SHM) of components in the industrial process is one of the crucial and important component of Industry 4.0. SHM of components exposed to high-temperature (similar to 650 degrees C) is becoming increasingly important nowadays. However, harsh and high temperature environments impose a great challenge towards their implementation. This review is an attempt to demonstrate the development, application, limitations and recent advancement of the existing sensors used for SHM. Some sensors such as eddy current (EC) sensors and fiber Bragg grating (FBG) sensors have been discussed in detail. A phenomenological study of the electromagnetic sensor for the SHM of engineering components that are exposed to high temperature has been addressed. State-of-the-art fabrication methodologies such as low-temperature co-fired ceramic (LTCC) technology for such type of sensors for high temperature SHM applications have been elucidated. Future challenges and opportunities for SHM applications of high temperature sensors have been highlighted
Annual Report 2020-2021
Get PDFIt contains the statement of R&D works undertaken, achievement made and the expenditure by the laboratory during the financial year 2020-202
Microstructure-mechanical property evaluation and deformation mechanism in Al added medium Mn steel processed through intercritical rolling and annealing
No full textThe present work investigates the microstructure evolution, mechanical properties and deformation mechanism in medium Mn high Al steel processed through intercritical rolling and subsequent intercritical annealing treatment at different temperatures. The annealed samples possessed a multi-phase microstructure consisting of intercritical ferrite/martensite, austenite and delta-ferrite. However, the morphology of the phases varied with annealing temperature. The result shows that annealing at a temperature of 730x25e6; and 780 x25e6;C led to the devel-opment of bimodal grain structure consisting of fine laths and equiaxed ultra-fine-grains (UFG) of ferriteaustenite; whereas annealing at 830 x25e6;C led to fully equiaxed coarse ferrite-austenite grains. An excellent combination of strength and ductility (product of ultimate tensile strength and elongation) as high as 56 GPa% was obtained in the 780 x25e6;C annealed sample. The chemical composition and grain size of austenite was found to be critical factors governing its stability. A mixture of lath and equiaxed austenite grains, having appropriate stability, in 780 x25e6;C annealed sample led to sustained four-stage strain hardening during deformation. Multiple work hardening mechanisms involving transformation induced plasticity (TRIP) effect, twin induced plasticity (TWIP) effect and discontinuous TRIP effect were found to occur sequentially in the equiaxed and lath-type austenite during the deformation that led to the extraordinary strength ductility combination
Photocatalytic TiO2 incorporated PVDF-co-HFP UV-cleaning mixed matrix membranes for effective removal of dyes from synthetic wastewater system via membrane distillation
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Journal of Environmental Chemical Engineering
Volume 9, Issue 5, October 2021, 105904
Photocatalytic TiO2 incorporated PVDF-co-HFP UV-cleaning mixed matrix membranes for effective removal of dyes from synthetic wastewater system via membrane distillation
Author links open overlay panelAnshulYadavacPreranaSharmaacAsit BaranPandabcVinod KumarShahiac
a
Membrane Science and Separation Technology Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, India
b
Advanced Materials and Processes Division, CSIR-National Metallurgical Laboratory, Jamshedpur 831007, India
c
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
Received 9 March 2021, Revised 15 June 2021, Accepted 17 June 2021, Available online 24 June 2021.
Editor: Despo Kassinos
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https://doi.org/10.1016/j.jece.2021.105904
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Highlights
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UV-cleaning PVDF-co-HFP/TiO2 mixed matrix membrane for DCMD.
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Controllable large-scale synthesis of porous TiO2 sheets by spray drying process.
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Effective removal of MB and CR dye from wastewater system by membrane distillation.
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High performance DCMD for five days without significant flux and rejection decline.
Abstract
We report membranes with UV-cleaning properties by incorporating photocatalytic porous TiO2 sheets (PTS) (0–5 wt%) in the PVDF-co-HFP matrix. PTS were synthesized using controllable large-scale synthesis protocols by spray drying followed by calcination. These membranes were assessed for the removal of Congo red (CR) and methylene blue (MB) from synthetic textile industry wastewater system (CR: 100 mg l−1 + MB: 100 mg l−1 + 4% NaCl) via direct contact membrane distillation (DCMD) configuration and their UV-cleaning properties. The PTS were characterized by FE-SEM, TEM and different spectral techniques, while membranes were assessed by surface morphology (FE-SEM, AFM), thermal stability, hydrophobicity, permeate flux, and dye rejection performance. The surface morphology study of PTS revealed its micro-sized sheet with the porous surface. With increased PTS concentration in the membrane matrix, the flux and dye rejection of mixed matrix membranes improved. Suitably optimized PT3 (3 wt% PTS in PVDF-co-HFP matrix) membrane showed ~100% dye removal efficiency (MB and CR) and 6.1 kg m−2 h−1 vapour flux. Long run (5 days) DCMD experiments showed >91% flux recovery ratio (FRR) after UV-cleaning. This study suggests the suitability of the prepared membranes to treat textile wastewater and their UV-cleaning properties
Mesoarchean continental intraplate volcanism and sedimentation: The case of the Simlipal basin, Singhbhum Craton, eastern India
No full textThe origin of continental intraplate basalts, their role in crust-mantle interaction, and processes of formation of the associated sedimentary rocks have remained important research problems. The poorly-studied Simlipal basin hosts a well-preserved, weakly-metamorphosed ensemble of three bands of mafic volcanic rocks intercalated with shallow marine sandstones and minor phyllites, occurring unconformably over a Paleoarchean continental basement of the Singhbhum Craton. Little is known about the age of the basin, the nature of sediment source and source weathering, petrogenesis of the volcanic rocks, and the tectonic setting of the volcano-sedimentary assemblage. To address these issues, we present whole-rock geochemical data on the Simlipal sediments and volcanic rocks, detrital zircon U-Pb ages and mineral chemical analyses. The sandstones and phyllites are characterized by high K2O/Na2O and chemical index of alteration. The source-indicating elemental ratios and REE patterns (negative Eu anomaly and flat HREE) suggest that felsic rocks, especially the granitoids resulting from shallow crustal melting, were the dominant source. The detrital zircons are mostly rounded with U-Pb ages ranging from 3.63 to 3.17 Ga. All these features suggest that the Simlipal basin formed during the Mesoarchean Era on a slowly subsiding continental platform undergoing extension, which received reworked and recycled sediments from a diverse but granitoid-dominated, intensely-weathered, mostly Paleoarchean source. The mafic volcanic rocks are low-Ti, tholeiitic basalts showing low CaO/Al2O3 and TiO2/Yb values, and flat HREE pattern indicating derivation from a spinel lherzolite mantle at shallow depth (<80 km). The presence of xenoliths of crustal rocks, quartz-normative nature, wide range of magnesium number (39-80), primitive mantle-normalized negative Nb, Ta and Ti anomalies, and high U/Nb and Th/Yb ratios reflect that the magma underwent significant fractional crystallization and crustal assimilation. The Simlipal volcanic rocks are consanguineous with the spatially close and coeval gabbro-anorthosite bodies, layered mafic-ultramafic rocks, and A-type Mayurbhanj Granite of the Singhbhum Craton, together forming an intraplate bimodal volcanic-plutonic association. We construe that the widespread Mesoarchean magmatism and sedimentation was linked to mantle upwelling possibly related to an event of lithospheric delamination and crustal extension
Synthesis of nano crystalline nickel by severe plastic deformation
No full textNickel rolled sheet of thickness 0.1 mm has been synthesized by severe plastic deformation. Repeated Cold Rolling, a new type of SPD method has been used and
thickness reduction up to 97.5% has been achieved, other reductions have also been performed .The lattice parameters, and the inter-planar spacings of the rolled nickel sheets has been determined using X-ray diffraction. Analysis of X-ray peaks indicated broadening which suggest smaller crystallite sizes. The average grain size of 0.1 mm thickness nickel rolled sheet has come to 850 nm. Grain sizes has been calculated using the image intercept method. Microstructure of rolled nickel sheets has been observed by optical and scanning electron microscopy (SEM)
Structural tailoring of ceria nanoparticles for fabricating fouling resistant nanocomposite membranes with high flux distillation
No full textThis study stems from the morphological design of ceria (CeO2) filler into the membrane matrix, which might provide a varied method for building nanocomposite membranes with superior performance. We synthesized nanostructured CeO2 with controlled size and shape using aqueous ceric ammonium carbonate complex (precursor) and decanoic acid under reflux and hydrothermal conditions. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP)/CeO2 nanocomposite membranes were fabricated through the phase inversion technique for desalination via direct contact membrane distillation (DCMD) using the synthesized CeO2 of various morphologies. The influence of CeO2 morphology on the performance of the membrane was investigated by various morphological and spectral techniques along with transmembrane flux and salt rejection. Among the fabricated membranes, (18% PVDF-co-HFP/1%) CeO2 (synthesized through hydrothermal route with 1:16 ratio of ceric ammonium nitrate to decanoic acid) -M-HT1:16 membrane was adjudged the most suitable with 5.33 L m(-2) h(-1) permeate flux and 99.98% salt rejection for desalination of 8% NaCl solution at 60 degrees C feed temperature. The smooth spherical morphology of CeO2 nanoparticles improved surface roughness, membrane porosity, and hydrophobicity for the M-HT1:16 membrane. A mathematical model was also proposed which describe the vapor flux profile of the DCMD process. The model was validated by experimental data with reasonable accuracy. Exceptional thermal stability, anti-fouling nature, along with feasible scale-up make MHT1:16 nanocomposite membrane a promising candidate for seawater desalination by the DCMD process
A comparative study on flotation of coal using eco-friendly single reagent and conventional dual-reagent system
No full textThe continuous depletion of low ash coals and raising demand of clean coal due to increase in consumption in various sectors such as iron and steel industries, the washing of high ash coal has become inevitable. Froth flotation is one of the beneficiation methods in coal washing that exploits the surface hydrophobicity difference between coal, that is naturally hydrophobic, and its associated ash forming minerals that are commonly hydrophilic in nature. This natural hydrophobicity of coal surface acts as an advantage in reducing the ash content of coal by flotation as it is a surface-phenomenon based separation technique. In this study, a coking coal with 25.75% ash was subjected to beneficiation by flotation at two different size fractions of 100% passing 0.5mm and 0.25mm. The flotation studies on these two size fractions was studied using commercially used collector and frother. A newly developed reagent, Collector AB, synthesized from natural percussor was used as as coal collector. The collectors AB is environmentally non-hazardous and safe to use in coal washeries unlike most commercial coal collectors and hydrocarbon oils that are being used at large scale. The process optimization of the flotation reagents was studied at two different size fractions of the coal sample and the flotation efficacy was found to be comparable. Hence, this developed reagent would be alternative to commercially available flotation reagents and other hydrocarbon oils presently being used for coal flotation
Utilization of limestone mineral wastes for developing self-compacting micro concrete
No full textThis study aims at investigating the feasibility of replacing cement and fine aggregate by limestone mineral wastes in developing Self Compacting Micro Concrete (SCMC). SCMC is highly flowable and can be used in places where there is no access to vibrators for compaction. Hence, these types of micro concretes are used mainly for repair purposes. The novelty of the work is that fines and coarse form of limestone mineral wastes generated during the beneficiation of a low-grade limestone ore has been studied for its utility as cement and fine aggregate substitute respectively in the preparation of SCMC. The main requirement for repair concrete such as flowability has been studied along with other mechanical properties. Flowability of mixes were assessed by mini slump test and V-funnel test. Mechanical properties namely compressive strength, flexural strength and split tensile strength tests were also studied to evaluate the performance efficacy. It was found that with 100% coarse limestone waste of less than 1mm in size as fine aggregate, it is possible to achieve about 25 MPa and 45 MPa compressive strength at 3 and 28 days respectively. As high flowability and early age strength are of significant parameters for the development of micro concrete, the mix made of 100% limestone wastes as fine aggregate is found to be a successful mix for sustainable development of micro concrete
Preparation of graphene oxide from coal
Get PDFNanomaterial synthesis from low-cost precursors is a highly desirable approach for bulk application in material science and technology. Among the various nanomaterials, graphene is a single layer two-dimensional honeycomb carbon nanomaterial. Graphene /or graphene oxide is widely utilized in material science, bio-medicine technology as a sensor, cellular imaging, and many more due to its surface area, nanoscale size, and electrical charge properties, etc. Coal is the most abundant combustible energy source. Although, coal possesses a very complex structure, however, it consists significant amount of polyaromatic structure. Due to the presence of an inherent polyaromatic structure, coal
becomes a promising candidate to replace graphite as a precursor material for the production of graphene / or graphene oxide. Herein, a facile cost-effective approach is reported to synthesize graphene oxide from low-grade coal