111 research outputs found
Health-based risk targets for fluorosis in tribal children of rural Madhya Pradesh, India
Conventional approaches to fluorosis mitigation and control are based on reduction of excess fluoride consumption from
water. Country specific standard limits of 1 mg/l or 1.5mg/l are established and monitored by water departments based on
recommendations outlined in the World Health Organization (WHO) Guidelines for Drinking Water Quality (GDWQ). With
the advent of the third edition of the WHO GDWQ there is a fundamental departure from standard setting, based on doseresponse
affect, towards risk assessment and risk management. The water quality framework, outlined in the guidelines,
consists of an iterative cycle, comprising: an assessment of risk, health targets linked to the wider public health context;
risk management (with these components being informed by aspects of environmental exposure and acceptable risk) The
guidelines advocate for the use of Water Safety Plans, as risk management tool, to help achieve Health Based Risk Targets.
This paper presents the application of a Quantitative Chemical Risk Assessment (QCRA) method for determining health
based risk targets for fluorosis control. The paper presents evidence from Madhya Pradesh, India. The findings indicate
firstly that to control fluorosis total daily consumption from all exposure routes (water and food) must be considered,
secondly that the most exposed population group to fluorosis are children due to lack of alternative early nutrients (e.g.
exclusive breastfeeding) and, thirdly, that quantifying chemical risk is essential for appropriate risk management strategies
to reduce fluorosis in children
Enhancing Knee Osteoarthritis severity level classification using diffusion augmented images
This research paper explores the classification of knee osteoarthritis (OA)
severity levels using advanced computer vision models and augmentation
techniques. The study investigates the effectiveness of data preprocessing,
including Contrast-Limited Adaptive Histogram Equalization (CLAHE), and data
augmentation using diffusion models. Three experiments were conducted: training
models on the original dataset, training models on the preprocessed dataset,
and training models on the augmented dataset. The results show that data
preprocessing and augmentation significantly improve the accuracy of the
models. The EfficientNetB3 model achieved the highest accuracy of 84\% on the
augmented dataset. Additionally, attention visualization techniques, such as
Grad-CAM, are utilized to provide detailed attention maps, enhancing the
understanding and trustworthiness of the models. These findings highlight the
potential of combining advanced models with augmented data and attention
visualization for accurate knee OA severity classification.Comment: Paper has been accepted to be presented at ICACECS 2023 and the final
version will be published by Atlantis Highlights in Computer Science (AHCS) ,
Atlantis Press(part of Springer Nature
Reducing Crystallinity of Micrometer-Sized TitaniumNiobium Oxide through Cation Substitution for High-Rate Lithium Storage
Characterisation of wastes from processing of sea nodules
The processing of polymetallic sea nodule by reduction-roasting ammoniacal leach process generates two types of wastes viz., spent liquor and nodule tailings. Spent liquor characterised so far with respect to its physical and chemical characteristics reveals that its discharge would have no deleterious effect on the surrounding environment. Further studies are being recycled in the process. Results obtained for leachate characterisation of nodule tailings so far is also very encouraging and this indicates that tailings generated from laboratory/pilot scale plant may be environmentally acceptable. This is judged from the fact that toxicity test conducted for leachates by Extraction Procedure (EP) shows that the nodule tailings produced in the laboratory are nonhazardous. None of the tailings exceed maximum allowable limit for eight regulated metals viz., Ag,As, Ba, Cd, Cr, Se, Hg and Pb
Au-TiO2 nanocomposites and efficient photocatalytic hydrogen production under UV-visible and visible light illuminations: a comparison of different crystalline forms of TiO2
Au[subscript (~1 wt%)]/TiO[subscript 2(anatase or rutile or P25)] nanocomposites were prepared by the solvated metal atom dispersion (SMAD) method, and the as-prepared samples were characterized by diffuse reflectance UV-visible spectroscopy, powder XRD, BET surface analysis measurements, and transmission electron microscopy bright field imaging. The particle size of the embedded Au nanoparticles ranged from 1 to 10 nm. These Au/TiO[subscript 2] nanocomposites were used for photocatalytic hydrogen production in the presence of a sacrificial electron donor like ethanol or methanol under UV-visible and visible light illumination. These nanocomposites showed very good photocatalytic activity toward hydrogen production under UV-visible conditions, whereas under visible light illumination, there was considerably less hydrogen produced. Au/P25 gave a hydrogen evolution rate of 1600 mol/h in the presence of ethanol (5 volume %) under UV-visible illumination. In the case of Au/TiO[subscript 2] prepared by the SMADmethod, the presence of Au nanoparticles serves two purposes: as an electron sink gathering electrons from the conduction band (CB) of TiO[subscript 2] and as a reactive site for water/ethanol reduction to generate hydrogen gas. We also observed hydrogen production by water splitting in the absence of a sacrificial electron donor using Au/TiO[subscript 2] nanocomposites under UV-visible illumination
Characterization, structural identification and environmental applications of flyash based zeolite
Hydrogen evolution by water splitting using novel composite zeolite-based photocatalyst
Novel zeolite-based material showing photocatalytic properties in the visible light have been synthesized by incorporating TiO2, heteropolyacid
(HPA) and transition metal, namely cobalt. This material shows high efficiency for water splitting under visible light irradiation. Hydrogen
generation to the tune of 2171 mmol/h/g of TiO2 has been achieved for the composite photocatalyst synthesized as compared to H2 evolution rate to
the tune of 131.6 mmol/h/g of TiO2 for Degussa P25. This suggests that the TiO2 which gets effectively dispersed and stabilized on the surface of
zeolite works synergistically with cobalt and heteropolyacid to make the material active in visible light for evolution of hydrogen from water. TiO2
is the photocatalyst, HPA functions as the dye sensitiser as well as redox system; zeolite functions as support matrix and as electron acceptor in
synergy with cobalt. The probable mechanism for improved hydrogen evolution rate using such composite photocatalyst has been discussed
UVand visibly active photocatalysts forwater splitting reaction
UV and visibly active photocatalytic materials based on zeolites have been designed, wherein, a hybrid photocatalytic material comprising
charge transfer complex namely, heteropolyacid, a semiconductor and transition metal have been incorporated in the zeolite matrix to facilitate
its usage for photoreduction of water to hydrogen. The photocatalytic materials synthesized using zeolite, TiO2 and heteropolyacid (HPA)
are active in the UV range and the hydrogen yield works out to be 3000 �mol/h/g of TiO2 catalyst in UV range, which is quite low as
compared to that reported in literature. The photocatalytic materials developed by incorporation of HPA, TiO2 and Co+2 are visibly active
and are performing well as compared to reported materials in terms of their photoreduction properties and show potential for water splitting
reaction in visible light. The maximum hydrogen yield works out to be 2304.9 �mol//h/g of TiO2 in visible range which is substantially high
as compared to other reported values for supported TiO2 based photocatalytic materials
Copper Oxide Nanograss for Efficient and Stable Photoelectrochemical Hydrogen Production by Water Splitting
A biphasic copper oxide thin film of grass-like appendage morphology is synthesized
by two-step electro-deposition method and later investigated for
photoelectrochemical (PEC) water splitting for hydrogen production. Further,
the thin film was characterized by UV–Visible spectroscopy, x-ray diffraction
(XRD), Scanning electron microscopy (SEM) and PEC techniques. The XRD
analysis confirms formation of biphasic copper oxide phases, and SEM reveals
high surface area grass appendage-like morphology. These grass appendage
structures exhibit a high cathodic photocurrent of � 1.44 mAcm�2 at an applied
bias of � 0.7 (versus Ag/AgCl) resulting in incident to photon current
efficiency (IPCE) of � 10% at 400 nm. The improved light harvesting and
charge transport properties of grass appendage structured biphasic copper
oxides makes it a potential candidate for PEC water splitting for hydrogen
production
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