20 research outputs found
Recent Advances in Environment-Friendly Alkyd Nanocomposites Towards “Greener” Coatings
Alkyd nanocomposites have attracted great attention in the field of heavy duty coating materials. This is due to the synergistic action of both alkyds (flexibility, biodegradability, compatibility, good gloss retention, durability, weathering resistance) and nanofillers (large surface area to volume ratio). Alkyd nanocomposites show good physico-mechanical, physico-chemical, anticorrosive, and antimicrobial performances and thermal stability, with application as anticorrosive, anti-fog, self-cleaning, self-healing, and antimicrobial coatings. In view of present drives and legislations towards environment-friendly coatings, alkyds have undergone modifications as waterborne, high solids, hyperbranched “greener” nanocomposites. The present chapter deals with a brief overview of alkyds, recent advances in environment-friendly alkyd nanocomposite coatings, and the effects of nanofillers on the performance (physico-mechanical, chemical/corrosion resistance, thermal stability, and others) of “greener” alkyd nanocomposite coatings
Effects and Consequences of Emphasizing Sectoral Recovery Rate and Sectoral Proportion in Loan Portfolio on Approving New Project Loans of Bangladesh Shilpa Bank
This study is designed for the identification of the effects and consequences of emphasizing the sectoral recovery rate and sectoral proportion in loan portfolio on approving new project loans of the Bangladesh Shilpa Bank (BSB). This study primarily focus on the role of sectoral recovery rate and the sectoral proportion of the loan portfolio, then conducts empirical studies considering the sacrifices of the profitability and growth opportunities, and leverage problem of the respective sectors. Empirical studies are conducted under two phases. The results of the empirical tests of Phase-I indicate the lack of reliability of the model under that phase in explaining the characteristics of the population. Empirical results of Phase-II have found significant results indicating the positive relationship of the sectoral recovery rate and sectoral proportion of loan portfolio in approving new projects. The empirical results have also found the evidence of approving project loans to high levered sectors. Keywords: Sectoral Recovery Rate, Sectoral Proportion in Loan Portfolio, Return on Investment, Debt to Asset Ratio
Method validation on iron determination by spectrophotometric method in aqueous medium
790-796This paper deals with the validation of a method for the determination of iron in spectrophotometric method in aqueous medium. The method is based on complex formation of iron with thioglycolic acid in alkaline medium in presence of a masking agent to produce a red purple chelate that has an absorption maximum at 535 nm wavelength. Beer-Lambert law is obeyed and linear calibration curves are obtained for the concentration range of iron from 0.1 mg/L to 30 mg/L. The reaction is found to be spontaneous in alkaline medium. The limit of detection and limit of quantification for the developed method are 0.0108 and 0.0345, respectively. Effect of different parameters like molar ratio of iron to different reagents and interferences, effect of time and effect of temperature of this method of determination have been studied. It is found that this method is moderately sensitive and has been successfully applied for the determination of iron(III) in different fields like ceramic materials, clay, sand, glass, stone, soil, water, and any inorganic iron containing compound or alloys. A comparison report is made for Chevron gas field waste material and Certified Reference Material of iron, which is done by atomic absorption and UV-visible spectroscopy techniques and found to be comparable
Method validation on iron determination by spectrophotometric method in aqueous medium
This paper deals with the validation of a method for the determination of iron in spectrophotometric method in aqueous medium. The method is based on complex formation of iron with thioglycolic acid (TGA) in alkaline medium in presence of a masking agent to produce a red purple chelate that has an absorption maximum at 535 nm wavelength. Beer’s-Lambert’s law is obeyed and linear calibration curves were obtained for the concentration range of iron from 0.1 mg/L to 30 mg/L. The reaction is found to be spontaneous in alkaline medium. The limit of detection (LOD) and limit of quantification (LOQ) for the developed method are 0.0108 and 0.0345 respectively. Effect of different parameters like molar ratio of iron to different reagents and interferences, effect of time and effect of temperature of this method of determination were studied. It is found that this method is moderately sensitive and has been successfully applied for the determination of iron (III) in different fields like ceramic materials, clay, sand, glass, stone, soil, water, and any inorganic iron containing compound or alloys. A comparison report is made for Chevron gas field waste material and Certified Reference Material (CRM) of iron, which was done by Atomic Absorption Spectrophotometer (AAS) and Ultraviolet-visible (UV-Vis) spectrophotometer and found to be comparable
Fabrication of Ferrous Sulfate from Waste Like Condensed Milk Containing Can and its Characterization
Ferrous sulfate is usually produced from the spent pickling liquor when the metal sheets are pickled in the processing of steel. In the present work ferrous sulfate was prepared by simple acid leaching method by using waste condensed milk can as a raw material. This can contains around 87 percent of iron which was successfully converted to greenish crystals of ferrous sulfate by simple acid leaching followed by crystallization. The process parameters like concentration of acid, molar ratio of iron to acid, period of reaction,effect of temperature and effect of occasional stirringwere optimized. Nearly 98% iron was leached out from iron containing can and converted to ferrous sulfate. The product was characterized by chemical analysis, thermo gravimetric analysis and X-ray diffraction analysis. On chemical analysis it was found that the produced product is highly pure, nearly 97 percent. According to the DSC/TGA studies, it is found that the prepared sample is hexahydrate. From X-ray diffraction pattern, it was confirmed that the prepared sample is ferrous sulfate with melanterite phase and have monoclinic crystal structure. Ferrous sulfate is usually produced from the spent pickling liquor when the metal sheets are pickled in the processing of steel. In the present work ferrous sulfate was prepared by simple acid leaching method by using waste condensed milk can as a raw material. This can contains around 87 percent of iron which was successfully converted to greenish crystals of ferrous sulfate by simple acid leaching followed by crystallization. The process parameters like concentration of acid, molar ratio of iron to acid, period of reaction,effect of temperature and effect of occasional stirringwere optimized. Nearly 98% iron was leached out from iron containing can and converted to ferrous sulfate. The product was characterized by chemical analysis, thermo gravimetric analysis and X-ray diffraction analysis. On chemical analysis it was found that the produced product is highly pure, nearly 97 percent. According to the DSC/TGA studies, it is found that the prepared sample is hexahydrate. From X-ray diffraction pattern, it was confirmed that the prepared sample is ferrous sulfate with melanterite phase and have monoclinic crystal structure
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Therapeutic Targeting of BMP and TGF-β Signalling Pathways for the Resolution of Pulmonary Arterial Hypertension
Vascular remodelling due to excessive proliferation and apoptosis resistance of
pulmonary arterial smooth muscle (PASMCs) and endothelial cells (ECs) has
been attributed to the pathogenesis of pulmonary arterial hypertension (PAH). It
is an incurable cardiovascular disorder, which leads to right heart failure and
death, if left untreated. Heterozygous germline mutations in the bone
morphogenetic protein receptor type II (BMPR2) have been linked with the
majority (~75%) of the familial form of the disease (HPAH). Mutations in the
BMPR2 gene impinge upon the BMP signalling which perturbs the balance
between BMP and TGF-β pathways leading to the clinical course of the disease.
Current therapies were discovered prior to the knowledge that PAH has
substantial genetic components. Hence, this study aims to identify novel
therapeutic intervention and provide novel insights into how the dysfunctional
BMPRII signalling contributes to the pathogenesis of PAH. This work
demonstrates that cryptolepines and FDA approved drugs (doxorubicin, taxol,
digitoxin and podophyllotoxin) inhibit the excessive proliferation and induce
apoptosis in BMPR2 mutant PASMCs by modulating the BMP and TGF-β
pathways. Moreover, established drug PTC124 has also been tested but has
failed to promote translational readthrough. I have also shown that dysregulated
apoptosis of PASMCs and HPAECs is mediated through the BMPRII-ALK1-BclxL
axis. Finally, the siRNA screen targeting approximately 1000 genes has
identified novel proteins including PPP1CA, IGF-1R, MPP1, MCM5 and SRC
each capable of modulating the BMPRII signalling. Taken together, this study for
the very first time has identified novel compounds with pro-BMP and anti-TGFβ
activities which may provide therapeutic intervention prior to or after the onset of
PAH.Commonwealth Scholarship Commission in the UKThe full text will be available at the end of the embargo period, 31st July 2024
Human Regular Activities Recognition Using Convolutional Neural Network
Capturing commonly occurring behaviors is a tough issue in computer vision. A few of them are recreation, touring, leisure pursuits, and religious practice. A comprehensive effort has already been dedicated to this aspect to deal with this issue. In this work, we recreated a dataset with five categories, including household activities, farming, exercise, sports, and occupation, to identify human daily actions. This collection has 4328 colored images in total, among them 630 are set aside for testing, and 3698 for training. Deep learning and standard image-based strategies are being explored to address the issues. In this paper, we have designed a deep learning paradigm to classify the regular activities of human beings. To characterize people's daily chores, we use the CNN model, one of the greatest tools for visual identification. We also have chosen two already-trained VGG16 and ResNet50 models. When we compare our model with the existing techniques, the investigation's findings demonstrate that the suggested network has a better recognition accuracy of 91%. Additionally, we have observed that accuracy varies throughout different epochs, and after 25 epochs we got better stable results from our model. The reader may find this article instructive in grasping CNN models for various recognizing applications
Impacts of annealing temperature on microstructure, optical and electromagnetic properties of zinc ferrites nanoparticles synthesized by polymer assisted sol-gel method
Nanocrystalline zinc ferrite (NZF) were successfully synthesized at different calcination temperature via sol-gel method from the precursor salt solutions using tartaric acid and PVA solution as a chelating agent and binder respectively. The characterization of NZF and their properties had been investigated using sophisticated techniques viz. X-ray diffraction, Fourier transform infra-red spectroscopy, Scanning electron microscopy, Transmission electron microscopy, Energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, UV–Vis-NIR spectroscopy, Vibrating sample magnetometer and Impedance analyzer. X-ray peak profile analysis through Debye Scherer and Wilson method, Halder-Wagner method has been used to estimate the structural parameters. The crystallite size and particle size of ZnFe2O4 samples were found to increases with increasing annealing temperature while lattice parameters and lattice strain decreases. Dynamic light scattering and zeta potential measurements were used to evaluate the particle size distribution and stability of these systems. The room temperature magnetic properties measurement showed that the net magnetic moment is observed for NZF due to cation distribution although the bulk ZnFe2O4 is non-magnetic. Direct optical band gaps of the prepared NZF samples has been investigated by UV–Vis NIR spectroscopy using Tauc formula and found that energy band gaps (Eg) values are in a narrow range of 1.19–1.86 eV. The frequency dependent dielectric properties, impedance and modulus spectroscopy measurement has been investigated in the frequency range of 100 Hz to 20 MHz. The synthesized NZF particles will be applied for Gas sensor, humidity sensor and photocatalyst