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81.

The most burning issues worldwide at present are the availability, accessibility, and affordability of the equitable healthcare services for all. It is getting more severe for developing countries due to increasing population and chronic diseases. The emerging technological interventions in the field of Internet of Things (IoT)-based healthcare systems are a promising solution to meet the general public's healthcare needs. Therefore, an IoT-enabled vital sign monitoring system has been presented in this paper. The presented system can monitor various vital signs in real-time and store the recorded trends locally. The system can also send the data into cloud for further analysis. Abnormality detection with alert notification and automatic calculation of early warning score has been implemented. An Android application is developed to store the vital signs records on a personal server to avoid the burden and maintenance cost of the central medical server. The presented system is straightforward, compact, portable and easy to operate through personal service application. Also, the presented system is compared with the most recent work available in the field.

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82.
83.
This article presents the effect of processing parameters on the ferroelectric hysteresis behavior of Ba0.85Sr0.15Zr0.1Ti0.9O3 (BSZT) ceramics. The ferroelectric hysteresis scaling relations for coercive field (Ec) and remnant polarization (Pr) as a function of temperature have been proposed. The power law temperature exponents based on scaling were systematically established for all the hysteresis parameters. The temperature dependent scaling of Ec and Pr at sintering temperature of 1400, 1425, 1450 and 1475°C yields EcαT0.43, EcαT0.84, EcαT0.50, EcαT0.37 and PrαT?1.73, PrαT?1.55, PrαT?1.73, PrαT?1.69 respectively. Additionally, the scaling relations for the samples sintered at 1450°C at different time intervals of 3, 4, 5 and 6 hrs were also established. Finally, to understand the domain dynamics, back switching polarization (Pbc) as a function of temperature (T) was also estimated by Arrhenius law and the average activation energy was evaluated.  相似文献   
84.
The Malayan box turtle (Cuora amboinensis) (MBT) is a vulnerable and protected species widely used in exotic foods and traditional medicines. Currently available polymerase chain reaction (PCR) assays to identify MBT lack automation and involve long targets which break down in processed or denatured tissue. This SYBR Green duplex real-time PCR assay has addressed this research gap for the first time through the combination of 120- and 141-bp targets from MBT and eukaryotes for the quantitative detection of MBT DNA in food chain and herbal medicinal preparations. This authentication ensures better security through automation, internal control and short targets that were stable under the processing treatments of foods and medicines. A melting curve clearly demonstrated two peaks at 74.63 ± 0.22 and 78.40 ± 0.31°C for the MBT and eukaryotic products, respectively, under pure, admixed and commercial food matrices. Analysis of 125 reference samples reflected a target recovery of 93.25–153.00%, PCR efficiency of 99–100% and limit of detection of 0.001% under various matrices. The quantification limits were 0.00001, 0.00170 ± 0.00012, 0.00228 ± 0.00029, 0.00198 ± 0.00036 and 0.00191 ± 0.00043 ng DNA for the pure meat, binary mixtures, meatball, burger and frankfurter products, respectively. The assay was used to screen 100 commercial samples of traditional Chinese herbal jelly powder from eight different brands; 22% of them were found to be MBT-positive (5.37 ± 0.50–7.00 ± 0.34% w/w), which was reflected through the Ct values (26.37 ± 0.32–28.90 ± 0.42) and melting curves (74.63–78.65 ± 0.22°C) of the amplified MBT target (120 bp), confirming the speculation that MBT materials are widely used in Chinese herbal desserts, exotic dishes consumed with the hope of prolonging life and youth.  相似文献   
85.
The dual role of electric field in the flash sintering process of conducting MnCo2O4 is demonstrated. The flash and conventionally sintered MnCo2O4 samples produced at different temperatures are characterized using energy dispersive X-ray and micro-Raman spectroscopy to elucidate the micro-level spatial distribution of evolved phases. Raman signal mapping over the two ways sintered samples exposes differently grown areas of cobalt oxide based secondary phase. Electrical conductivity of conventionally sintered sample is recorded as a function of temperature and E-field and is utilized to discover the charge carrier activation mechanism during the flash effect. The conductivity before the flash-onset is shown to be comparable to that occurs by Poole-Frenkel effect and Phonon-assisted tunneling i.e. by the mechanism that occurs before the dielectric breakdown of semiconductors and insulators. The observed results, finally, confirm that catalyst like drift action of E-field on cobalt oxide formation is responsible for enhancement in the flash-sintering.  相似文献   
86.
Heat and mass transfer of non-Newtonian fluids is increasingly being studied by researchers due to its applications in many branches of science and engineering, such as metallurgical processes, polymer extrusion, glass blowing, crystal growing, and so forth. The present work is mainly concerned with the unsteady laminar magnetohydrodynamic flow of a heat-generating or absorbing second-grade fluid past an infinite vertical porous plate. The nondimensional governing equations are solved for the best analytical solution. Results for various flow characteristics are presented through graphs and tables delineating the effect of various parameters characterizing the flow. For engineering interest, the shear stresses, Nusselt number, and Sherwood number are computed and exchanged of views with reference to the important parameters. Our analysis explored that the influences of a chemical reaction and fluid oscillations reduced the concentration distribution in the entire liquid region. The rotation effect decreases the shear stress, whereas it is augmented through an increase in the permeability of porous medium and second-grade fluid parameters' impact.  相似文献   
87.
A novel class of polymer–metal complexes was prepared by the condensation of a polymeric ligand with transition‐metal ions. The polymeric ligand was prepared by the addition polymerization of thiosemicarbazides with toluene 2,4‐diisocyanate in a 1 : 1 molar ratio. The polymeric ligand and its polymer–metal complexes were characterized by elemental analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, and 13C‐NMR and 1H‐NMR spectroscopy. The geometries of the central metal ions were determined by electronic spectra (UV–visible) and magnetic moment measurement. The antibacterial activities of all of the synthesized polymers were investigated against Bacillus subtilis and Staphylococcus aureus (Gram positive) and Escherichia coli and Salmonella typhi (Gram negative). These compounds showed excellent antibacterial activities against these bacteria with the spread plate method on agar plates, and the number of viable bacteria were counted after 24 h of incubation period at 37°C. The antibacterial activity results revealed that the Cu(II) chelated polyurea showed a higher antibacterial activity than the other metal‐chelated polyureas. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
88.
Polyesteramide (PEA) and alumina‐filled polyesteramide (APEA) resins were synthesized from N,N′‐bis(2 hydroxyethyl) linseed amide. The FTIR, 1H‐NMR, DSC, TGA, thermal curing, and physico‐chemical characterization of these polymers were carried out. The coatings of PEA and APEA were made on mild steel strips. The mechanical behavior and protective efficiency of these coatings in acid, alkali, and organic solvents were investigated. APEA coatings have been found to show superior performance in comparison to other coatings. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1679–1687, 1999  相似文献   
89.
The corrosion inhibition of mild steel in 1 M HCl solution by Streptomycin has been studied by Tafel polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurement. The inhibitor showed 88.5% inhibition efficiency at optimum concentration 500 ppm. Results obtained revealed that inhibition occurs through adsorption of the drug on metal surface without modifying the mechanism of corrosion process. Potentiodynamic polarization studies suggest that it is a mixed type of inhibitor. Electrochemical impedance spectroscopy techniques were also used to investigate the mechanism of corrosion inhibition.  相似文献   
90.
In this study, the tensile behavior of clay-filled unsaturated orthophthalic polyester composites was evaluated. Specifically, ultimate strength, yield strength, fracture strain, and Young's modulus of two composites with small but varying fractions of clay particulates were determined. Several predictive approaches were considered for correlation with experimental values. Only the Young's modulus of the composites could be predicted satisfactorily. The irregular shape and size distribution of clay particulates seriously complicate attempts to analytically model the mechanical behavior of filled composites. Microcracking response of the composites was evaluated using an acoustic emission (AE) technique. The addition of clay is shown to embrittle the composites and is confirmed by the AE count rate and amplitude distribution data. Scanning electron microscopy of the fracture surface shows evidence of flaw initiated fracture. This study provides an insight into the influence of clay particulates in altering the properties of a polyester matrix.  相似文献   
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