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In India, water contamination is a serious environmental issue. Untreated sewage is typically the main cause of water contamination in India. Protecting water quality for sustainable livelihoods and poverty reduction becomes a greatest challenge with the technological change and population growth. Measurement of Water Quantity and Real Time Monitoring becomes mandate to advance the water stewardship. In this paper, to keep track of the quality, smart water quality monitoring system(Ph, temperature, turbidity) and analysing of water quantity (flow or level) based on IOT is proposed for the study area of Okkiyam Maduvu, watershed in Chennai. This system is implemented using various sensors to measure the water quality like Ph, temperature, turbidity sensor and for analysing water water quantity used flow or level sensors. All these sensors are controlled by using the microcontroller - Arduino ESP32. This proposed system is placed in the study area Okkiyam Maduvu watershed to monitor water quality and quantity and visualized those sensed data using the IOT platform through Blynk App. This helps to know the water level and its quality of Okkiyam Maduvu watershed and it helps to take necessary precaution if the water quality is reduced and its level raised beyond the level. [ABSTRACT FROM AUTHOR]

Eco-friendlybiosynthesis of silver nanoparticles (Ag NPs) and gold (Au NPs) nanoparticles by using Punica granatum and C. reticulata extracts were synthesized efficiently. Ag and Au NPs with sizes 8–10 nm and 30–40 nm were successfully synthesized and extracts serve as capping agents. Forming of NPs was confirmed through UV-visible spectra, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR) studies. The effect of NPs on the luminescence of Eu(TTFA)3 and Sm(TTFA)3 complexes was investigated. Luminescence intensities of the complexes were enhanced several times in the presence of silver and get quenched due to reabsorption of Au NPs. The nonlinear optical properties of NPs were calculated using open aperture Z-scan and degenerate four-wave mixing in the femtosecond region. The toxicity and antimicrobial activities of Ag and Au NPs were studied. [ABSTRACT FROM AUTHOR]

An ethnomedicinal survey was undertaken to cram the diversity of medicinal plants in the Manar beat of Karamadai Range, Coimbatore forest division, Western Ghats of Tamil Nadu, India from 2018-2019. The indigenous knowledge of local traditional healers and the native plants used for medicinal purposes were collected in their local language. The ethnobotanical data such as a local name, medicinal uses and mode of preparation was collected through structured questionnaires, personal interviews and consultation with very old and knowledgeable persons in and around the study area. The meteorological information of the study territory was recorded and tabulated. The present study enumerates a total of 104 medicinal plant species of 86 genera and 52 families are documented for the first time. Among these Fabaceae, Mimosaceae and Asclepiadaceae with 7 species are dominant over other families. Herbs are the most widely present life forms followed by trees. Amongst the different plant parts, leaves are the most widely used plant part in therapeutics and also for herbal formulations. According to IUCN threat status, Pterocarpus marsupium Roxb. (NT) is in the Near Threatened category, 2 species on this list are under the Endangered (EN) and in Vulnerable (VU) category. Those plants which fall under the vulnerable and endangered category are prescribed for germplasm collection. Therapeutic uses of medicinal plants and their active principles were also reported. Decoction is mostly utilized in the mode of preparation. The traditional healers are lessening in number and there is a grave hazard of traditional information disappearing soon. Since the younger generation isn't interested to carry on this custom. The study dazzled that this area is more pertinent to the conservation of local flora. So, documenting the traditional knowledge is important for sustainable utilization. [ABSTRACT FROM AUTHOR]

Experimental and computational investigations have been conducted to characterize the flow field in the supersonic ejector, with and without secondary inlets of two sizes, at stagnation pressures of 2, 2.5, 3, 4 and 5 bar. In the first case, four secondary inlet openings each with 5 mm diameter are provided on the suction chamber circumferentially. In the second case, four secondary inlet openings each with 10 mm diameter are provided on the suction chamber circumferentially. These two cases are investigated separately, at all the stagnation pressures. The wall pressure variation is validated based on the k-γ SST turbulent model with experimentally measured wall pressure distribution at 2 bar, without secondary inlet flow. Suction is found to increase with the increase of stagnation pressure in the suction chamber. The inducted mass flow promotes the mixing in the shock-train zone, by triggering the significant momentum exchange between the primary flow and secondary flow. Results show that the pressure recovery takes place as the flow enters the divergent portion of ejector. [ABSTRACT FROM AUTHOR]

Cu2O-Ag nanoheterostructure was synthesized by a simple and eco-friendly co-precipitation method, and its morphologic structure, linear and nonlinear optical properties were studied. Though pure Cu2O nano- and microparticles are known for their nonlinear absorption properties, current studies show that Ag nanoparticle in contact with Cu2O can significantly change the nonlinear response. When compared to pure Cu2O, our results indicate that Cu2O-Ag composite shows a saturable absorption behavior at lower excitation powers and flips to reverse saturable absorption at higher excitation powers. The composite also results in the bandgap modification and opens an extra window for two-photon absorption, while the excited state absorption was more probable in pure Cu2O. Interband transition occurs in Ag nanoparticle due to simultaneous two-photon absorption when excited by 532 nm. The excited carriers decay through nonradiative relaxation processes, leading to an increase in the nonlinear scattering mechanism, and the nonlinear scattering is found to increase with the excitation intensity. TEM data reveal the formation of spherical nanoheterostructure of Cu2O and Ag nanoparticles of ~ 30 nm diameter. XRD analysis provided further insight into the morphologic structure. [ABSTRACT FROM AUTHOR]

The present work deals with an inclined magnetohydrodynamic flow of a micropolar fluid occurring between two stretchable disks rotating co-axially at a constant distance apart by taking into account higher order chemical reaction effects. Using similarity variables the Navier–Stokes equations, which represent the momentum, microrotation, energy, and concentration, are transformed into ordinary differential equations. The transformed conservation equations are solved numerically by using the Nachtsheim–Swigert shooting iteration technique along with sixth-order Runge–Kutta integration scheme. The influence of governing parameters are shown graphically and discussed. It was observed that an increase in the aligned angle strengthens the applied magnetic field and decreases the momentum boundary layer profiles of the micropolar fluid flow. Heat transfer rate reduces for larger values of chemical reaction Cr for both n = 1 and n = 2. [ABSTRACT FROM AUTHOR]

Irula tribes in india live in rural areas under poor infrastructure, high poverty, low education, ignorant on the origin of diseases. Although, their lifestyle made them vulnerable to a variety of infectious diseases. Only few studies have been conducted on them, hence, there is inadequate data about these Irula tribal health. Serum samples were collected from 372 Participants of Irula tribes from 15 different locations of Tamil Nadu. Serum samples were tested for Hepatitis C Virus (Anti-HCV) by 3rd generation ELISA kit and data were subjected to analysis using SPSS (version 17.0) and Chi square test to determine the risk factors of Hepatitis C virus. HCV prevalence was 5.10 % and this percentage was high among females than males with the age group of 31 to 40. Among the various risk factors, were statistically analyzed (p<0.05) with HCV infection. The frequency of combination of risk factors were found in HJ+A+IDU+SI+M (100 %), A+IDU+SP (100 %) in Anti-HCV positive Irula tribes of Tamil Nadu. High prevalence of HCV infection was observed among the tribal population with the various risk factors such as series of injection, surgery with or without blood transfusion, tattooing sexual promiscuity, migration, jaundice in family and intravenous drug use. [ABSTRACT FROM AUTHOR]

A mathematical model is developed to examine the effects of radiation and slanted magnetic on boundary layer flow of a micropolar fluid containing gyrostatic microorganisms through a vertical fixed or continuous moving porous plate. The governing boundary layer equations are cast into a matrix form and solved analytically by utilizing the state space approach and the inversion of the Laplace transform is carried out, utilizing numerical approach. Numerical outcomes for the momentum, microrotation, density of motile microorganism and temperature distributions are given and illustrated graphically for the problem. Excellent agreement is found when present solutions are compared with the numerical solutions by utilizing the Crank–Nicolson implicit finite difference method. It is found that the density of the motile microorganisms is increasing functions of the bioconvection Lewis number in both cases moving and fixed plate. [ABSTRACT FROM AUTHOR]

Biodegradable hybrid composites Chitosan/para-phenylenediamine (CS/pPDA), montmorillonite/chitosan/para-phenylenediamine (Mt/CS/pPDA), chitosan/ortho-phenylenediamine (CS/oPDA) and montmorillonite/chitosan/ortho-phenylenediamine (Mt/CS/oPDA) clay polymer nanocomposites (CPN) were successfully synthesized. The CPN composites were confirmed by using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), UV–Vis spectroscopy and photoluminescence (PL) measurements. The nonlinear optical properties (NLO) of CPN were studied by using Z-scan technique in the picosecond (ps) and femtosecond (fs) durations. Open aperture Z-scan studies revealed reverse saturable absorption (RSA) behavior, which gives nonlinear absorption and closed aperture data revealed nonlinear refraction in both time domains. Sign and magnitude of the third order nonlinearity were evaluated. Optical limiting characteristics of the systems for optical switching were examined. Hence, the new CPN can be used as optical limiters. [ABSTRACT FROM AUTHOR]

An investigation has been carried out to study the effect of hydrodynamic boundary layer flow over an unsteady porous stretching surface in the presence of non-uniform heat source/sink. Heat transfer characteristics are examined for variable wall temperature and variable heat flux of boundary conditions. The governing equations are transformed to ordinary differential equations by similarity transformation and solved numerically by Runge-Kutta fourth order method in association with quasilinear shooting technique. The effects of unsteadiness parameter, permeability parameter, magnetic parameter, Prandtl number and heat source or sink parameter are represented graphically and discussed. [ABSTRACT FROM PUBLISHER]

Transmission loss (TL) of a simple expansion chamber (SEC) consists of periodic domes with sharp troughs. This limits practical application of the SEC in the variable-speed automobile exhaust systems. Three-fourths of the troughs of the SEC can be lifted by appropriate tuning of the extended inlet/outlet lengths. However, such mufflers suffer from high back pressure and generation of aerodynamic noise due to free shear layers at the area discontinuities. Therefore, a perforate bridge is made between the extended inlet and outlet. It is shown that the TL curve of a concentric tube resonator (CTR) can also be lifted in a similar way by proper tuning of the extended unperforated lengths. Differential lengths have to be used to correct the inlet/outlet lengths in order to account for the perforate inertance. The resonance peak frequencies calculated by means of the 1-D analysis are compared with those of the 3-D FEM, and appropriate differential lengths are calculated. It is shown how different geometric characteristics of the muffler and mean flow affect the differential lengths. A general correlation is obtained for the differential lengths by considering seven relevant geometric and environmental parameters in a comprehensive parametric study. The resulting expressions would help in design of extended-tube CTR for wide-band TL. [ABSTRACT FROM AUTHOR]