To investigate electronic properties, such as dielectric permittivity, dielectric loss, conductivity, capacitance, and Nyquist plots, acrylonitrile butadiene styrene (ABS) and β-CuPc (10–40 wt % of ...β-CuPc) formulation was utilized to fabricate nanocomposite films via the cost-effective solution processing technique. Cross-sectional morphological investigations were performed for the developed composites with the aid of Field emission scanning electron microscopy microscopy; the result suggested that the modified cross-sectional surface morphology was due to the addition of the β-CuPc compound. Further, the interactions-attributable phase groups of the polymer with the β-CuPc compound were studied by Fourier-transform infrared spectroscopy. The UV–vis spectroscopy result suggested that the absorption peak at 380 nm belongs to π–π* transition, which corresponds to intense B-band (Soret band) of Cu-Phthalocyanine ring, which significantly instigates the electronic conduction mechanism. Further, to understand the electronic properties, a broad-band impedance analyzer was utilized, wherein dielectric permittivity at <10 Hz was found to attribute due to the Maxwell–Wagner–Sillars polarization mechanism. Subsequently, frequency-dependent permittivity (103–107 Hz) was comprehended by the dipole polarization mechanism. The realization of composite’s permittivity increment from 4.6 to 5.1 at 107 Hz was due to the oriental resonance phenomena. Moreover, a composite with a maximum conductivity (σAC) of 2.1 × 10–6 S/cm was observed, which is attributable to the π–π* transition (380 nm), as evidenced by UV–vis spectra. Although the composite reveals higher conductivity, at higher frequency, low loss characteristics (>10 MHz ∼ 0.049) were observed of β-CuPc/ABS. These low loss characteristics are a remarkable outcome of nanocomposites at MHz frequencies. Therefore, the authors believe that these nanocomposite films fabricated via the cost-effective solvent cast film technology could facilitate to develop organoelectronic components or devices.
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IJS, KILJ, NUK, PNG, UL, UM
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•Smart phone assisted on-site monitoring of glucose is discussed.•CuO@rGO nanocomposites displayed amplified intrinsic peroxidase mimetic property.•The developed sensor has shown good ...selectivity with a lower detection limit of 7.0–8.0 μM in a linear range from 1 to 10 mM (R2 = 0.98–0.99).•The accuracy of the as-proposed sensor is investigated with the standard addition method (recovery 99–102%).•RGB software is designed and developed for analysing the data obtained through digital image colorimetry (DIC) method.
On-site monitoring of some specific health-related problems is continuously increasing and become a prime aspect of the scientific community. Herein, we have developed a user-friendly colorimetric sensor for rapid and unaided eye detection of glucose using a novel nanozyme (CuO@rGO) synthesized by decorating CuO nanoparticles over a reduced graphene oxide sheet (rGO) using an ultrasonication method. CuO@rGO nanocomposites displayed amplified intrinsic peroxidase mimetic property and catalyzes the oxidation of the chromogenic substrate, 3,3′,5,5′-tetramethylbenzidine (TMB) with the existence of electron acceptor H2O2 to produce blue coloured charge transfer product. The developed sensor has shown good selectivity with a lower detection limit of 7.0–8.0 μM in a linear range from 1 to 10 mM (R2 = 0.98–0.99). The accuracy of the as-proposed sensor is investigated with the standard addition method (recovery 99–102 %) and validated with a commercially available Glucometer. The proposed novel colorimetric sensor has good potential for the sensitive and selective determination of glucose in the buffer as well as in human blood samples. In addition, a modest, economic, portable, and smartphone-assisted digital image colorimetry (DIC) method is proposed for glucose sensing using RGB software analysis. This work opens a new prospect in clinical diagnosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recent progress in wearable biomedical devices has made real-time monitoring possible through non-invasive wearable strain sensors, which can transform physical or biological signals into electrical ...responses. This work has fabricated multifunctional wearable strain sensors by coating composites (SiE-µG) of electrochemically exfoliated micro-sized multi-layer graphene flakes (µG) and Silicone elastomer (SiE) onto stretchable textile-based orthopedic bandage having ZnO adhesive (SiE-µG@Bandage). The composite coated textile sensors exhibited a remarkable sensitivity of 18330, large stretchability of 35%, superior mechanical durability of 50000 cycles, minute detection limit of 0.04% strain, and fast response time of 400 and recovery time 900 ms. The SiE-µG@Bandage also showed antibacterial properties against Escherichia coli (E. coli) bacteria. Additionally, zinc oxide-based skin-friendly and non-toxic adhesive on the backside of the bandage allowed stable and conformal attachment with the skin. Owing to the above merits, the sensors have shown applicability in real-time monitoring of various physical activities, physiological signals, joint movements, yoga postures, and meditation. Furthermore, the relevance of the sensors in the man-machine interaction has been demonstrated via real-time monitoring of traffic signals by finger movements. Moreover, the exceptional performance and specific features of the SiE-µG@Bandage sensors have enabled their application as electronics skins in health care and preventive care.
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•Sensors are fabricated using the screen-printing technique, employing synthesized multilayer graphene-infused conductive paste.•Sensors displayed remarkably high Gauge Factor of 18330, and exceptional durability of 50,000 operational cycles.•The minimum strain detection limit of 0.0004.•Sensors exhibited antibacterial characteristics against Escherichia coli.•Demonstrated applicability in human health monitoring.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract We have investigated the potential of three dielectric materials to meet the future demands of green dielectrics: Polycaprolactone (PCL) thermoplastic, polyvinyl alcohol (PVA)‐carrageenan ...(CAR) crosslinked biopolymer, and boron nitride nanotubes (BNNTs) as a nano additive in PVA. Metal–insulator–metal (MIM) capacitors and organic thin film transistors (OTFT) were built with bilayer dielectric stacks of PVA‐CAR, PVA‐PCL, and PVA‐BNNT materials to examine their electrical properties. The PVA‐CAR layer uses a cyclic freeze thaw process to crosslink PVA and CAR for superior mechanical and electrical properties to either material alone. The PVA‐CAR MIM capacitors showed a dielectric constant of 23, which was found to be consistent with the extracted OTFT gate dielectric characteristics. Of the OTFT devices tested, PVA‐CAR OTFT showed highest device currents at low applied biases and produced an ON/OFF ratio of 10 4 –10 5 , both values were highest amongst the tested gate dielectrics. This material is therefore extremely promising for green electronics. The PVA‐PCL OTFT had very low leakage current and beneficial hydrophilic properties with comparable electrical properties to the commonly used organic material polytetrafluoroethylene. PVA‐BNNT MIM capacitors showed a low dielectric constant of 0.7, and the high resistivity makes this a promising material for shielding or substrates in high frequency applications. All three materials have the potential to fulfil different niches in a sustainable electronics future.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
495.
E-LEARNING FRAMEWORK FOR SEMANTIC-WEB Prakash, Ravi; Kumar, Somesh
Turkish journal of computer and mathematics education,
01/2021, Volume:
12, Issue:
14
Journal Article
Open access
Over the last few decades, growth in Information Technology field has been very rapid and the various Information Technology-dependent applications are also evolving very dramatically. Web learning ...and teaching might be one of the common Information Technology applications. The study's major purpose is to investigate and then compare several web-based e-learning systems.We are willing to include some recommendations about shortcomings that have been found based on empirical, comparative studies of such different frameworks. In order to create successful changes to the smart web e-learning frameworks structure to provide social dimensions of online classrooms, we therefore emphasize a few of the research challenges as well as design problems which have been pursued.
Electrolyte active group (EAG) embedded structured hard segments have been developed via graphene oxide coupled with polyurethane chain. The polysulfide redox couples (S2-/Sn2-) free functionalized ...polyurethane electrolyte possesses electron donating pendant anions (carboxylate and sulfonate segments) with sufficient oxygenic functional groups on polyurethane backbone. Polyelectrolyte activity is due to elevation of number density of pendant anions (electrolyte active group) into polyurethane chain. Electrochemical impedance spectroscopy (EIS) reveals higher electrical conductivity (4.48 × 10−3 S/cm) for optimized PUI-GO (0.5 wt%) electrolyte. The electrolyte active groups are prone to facilitate photovoltaic reaction due to synergistic interaction and function with MPA capped CdS. The QDSSC (FTO-RGO/TiO2/MPA-CdS/PUI-GO/FTO-Pt) exhibits maximum power conversion efficiency (1.63 %) and open circuit potential (VOC = 0.594 V) under 1 sun (100 mW/cm2) photo illumination. VOC is found to be improved with PUI-GO electrolyte due to its multi-functional activities such as expanded electrocatalytic area, conducting nanochannel and interfacial passivation effect of carboxylate ion on photoanode.
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•Tagging of graphene oxide within the polyurethane chain and subsequent functionalization to generate electrolyte active pendant anion suitable for photovoltaic redox reaction.•Preparation of MPA capped CdS quantum dot for the active material in solar cell.•Fabrication of solar cell using quantum dots and gel polyelectrolyte as hole transporting layer.•The resultant QDSSC exhibited open circuit potential (Voc = 0.594V) and photovoltaic conversion efficiency (η = 1.63%).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background:
Green tea polyphenols (GTP) are known to have several health benefits. In spite of these benefits, its application
as a therapeutic agent is limited due to some of its limitations such as ...stability, bioavailability, and biotransformation. To
overcome these limitations, liposomal nanoparticles have been used as a carrier of the GTP.
Objective:
Encapsulation of GTP to the liposomal nanoparticles in order to achieve a sustained release of the GTP and to
determine the drug release kinetics and the mechanism of the release.
Materials and Methods:
GTP encapsulated liposomal nanoparticles were prepared using phosphatidyl choline and
cholesterol. The synthesized particles were characterized for their particle size and morphology.
In vitro
release studies
were carried out, followed by drug release kinetics, and determining the mechanism of release.
In vitro
, antioxidant assay
was determined following 2,2-diphenyl-1-picrylhydrazyl (DPPH) method.
Results:
Atomic force microscope (AFM) and high resolution scanning electron microscope (HR SEM) images showed
spherical particles of the size of 64.5 and 252 nm. An encapsulation efficiency as high as 77.7% was observed with GTP
concentration of 5 mg.mL
-1
.
In vitro
release studies showed that the loading concentrations of GTP were independent to
the cumulative percentage of the drug release. GTP release by varying the pH and temperature showed a direct correlation
between the release parameter and the percentage of drug release. The higher the pH and temperature, the higher was the
percentage of the drug release. The release data showed a good correlation with Zero order kinetics and the mechanism of
the release being anomalous mode. Radical scavenging activity of the released GTP showed a potent scavenging activity.
Conclusion:
GTP encapsulated liposomal nanoparticles could be used as a delivery vehicle for achieving a sustained release.
Maheshwaram watershed is situated in Ranga Reddy district of at a distance of about 30 km south of Hyderabad. The watershed has an area of 53 km
2
and has hard rock aquifers with semi-arid climate. ...The study area has been expanding at a fast pace and now has the distinction of being one of the fastest growing urban centers, facing the problem of groundwater depletion and quality deterioration due to the absence of perennial source of surface water and also due to over exploitation. Human activities involving industrial and agricultural development and the inadequate management of land and water resources have, directly or indirectly resulted in the degradation of environment viz. water and soil.
In the present study chemical analysis of groundwater samples of the study area, collected in pre- and post-monsoon has been carried out. The analysed data is utilized to characterize the hydro chemical process dominant in the area. Various classification methods such as Piper, Back and Hanshaw, Wilcox, U.S. Salinity Laboratory are employed to critically study the geochemical characteristics of groundwater.
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EMUNI, NUK, SBMB, SBNM, UL, UPUK
Most of the studies on changes in heart rate variability (HRV) parameters in yoga are short-term, which are meant to gauge the cross-sectional change in HRV during or after an intervention. ...yoga ...is a lifestyle practice where changes setting in are slow and set in over a day-to-day basis. ...we are of the opinion that sequential recording during practice or at rest on day-to-day basis with short-term HRV protocol will be more fruitful as it will help us to see the sequential changes in HRV brought about by regular practice of yoga. Upon sequential recording of these parameters, we will be able to gauge the optimal level of sympathetic stimulation, which is required for the optimal performance of an individual and also that when it levels off (does not decrease beyond a level). ...short-term repeated assessment of HRV is helpful in evaluating time required for beneficial effects to set in and to assess the maximal beneficial effect derived out of its practice in maintaining better cardiac health.
Background: Aggressive periodontitis (AP) is a complex disease whose phenotype is determined by genetic and environmental influences on the affected individuals. About 45% of the adult population in ...India has periodontitis. In Tumkur district of Karnataka, India, consanguineous first cousin and uncle-niece marriages are common, with a high incidence of AP. These discrepancies in the expression of periodontal disease directed us to find genetic etiology with respect to the Tumkur population. The clinical and genetic aspects of AP from this area have been presented in this paper. Materials and Methods: A total of nine families were ascertained at the Department of Periodontics, Sri Siddhartha Dental College and Hospital (Sri Siddhartha University), Tumkur. The clinical and radiographic data were gathered according to 1999 Consensus Classification of Periodontal Diseases. Peripheral blood samples were collected for total genomic DNA isolation using a Wizard TM Genomic Purification Kit (Promega, USA). The homozygosity mapping was carried out in a large consanguineous family to map a novel locus using autosomal markers from the CHLC/Weber Human Screening Set 10 (Research Genetics Inc., USA) at Indian Institute of Sciences, Bangalore. Results: The pedigree analysis suggested that the disorder is segregating as an autosomal trait. The homozygosity mapping failed to identify a locus for generalized AP in the family. Conclusion: The disorder may not be segregating as an autosomal recessive trait and we could have been misled by consanguinity in the family. It could be a multifactorial trait, or it could be still segregating as an autosomal recessive trait, but the region of homozygosity could be small and we failed to detect it using microsatellite markers. Therefore, SNP-marker-based analysis is warranted in future.
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