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Farming is an essential sustenance for the progressive population. The development of our country depends on the farmers. Plants endure by many diseases due to environmental factors. So, the farmers need to detect plant diseases at an early stage for appreciable yield. In the beginning, the observing and examining plant disease are examined physically by the expertise in the farming field, which requires a considerable measure of work/ and requires over the top handling time. Now, machine learning concepts eliminate conventional protruding and time-consuming techniques. This paper focuses on a novel method for detecting and identifying paddy leaf diseases at the early stages in Thanjavur region using radial basis function neural network (RBFNN) classifier. Further, it is optimized with salp swarm algorithm (SSA) technique. The proposed method utilizes the data from the TNAU agritech portal, IRRI knowledge bank, UCI machine learning repository databases, which have healthy and diseased images. This work illustrates four categories (Bacterial Blast, Bacterial Blight, Leaf Tungro and Brown Spot) of infected paddy images along with the normal set of images. Initially the preprocessing is performed for the acquired images then K-means segmentation algorithm segregates the image. Gray level co-occurrence matrix extracts the Texture features from the segmented image and the RBFNN classifier performs the disease classification and improves the detection accuracy by optimizing the data using SSA. The investigational results of the proposed methodology exhibit the performance in terms of accuracy of disease detection is 98.47%. However, radial basis function neural network (RBFNN) achieves the diseases detection accuracy of 97.85% and support-vector machine (SVM) classifier achieves a disease detection accuracy of 97.07%. This paper proposes a method of paddy leaf disease recognition and classification using RBFNN and salp swarm algorithm. It also suggests and identifies an image analysis by framing a set of conditions for disease affected plants. The results show that the most satisfactory outcome can be gained to verify the yield of proposed methods with least effort. [ABSTRACT FROM AUTHOR]

Self-assembled monolayers of 3-mercapto-1 H-1,2,4-triazole (MTA) was formed over a copper surface at various immersion periods. Fourier transform infrared spectroscopy and cyclic voltammetry were used to characterize the films. Atomic force microscopy and scanning electron microscopy were employed for the characterization of surface morphology. The wettability of the film was examined using contact angle measurements. The corrosion protection ability of the films was assessed in a chloride solution using electrochemical impedance spectroscopy and polarization measurements. The results of the study clearly ascertained the protection ability of self-assembled films of the MTA over copper. The theoretical studies also vouched for the experimental results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sonochemical-assisted green of synthesis of AgNPs was achieved using avocado (AV) seed extract. • The AV-AgNPs were characterized using UV–vis, FTIR, DLS, FE-SEM and EDX. • The average particle size was found to be 119 nm. • The AV-AgNPs were served as colorimetric probe for the sensing of toxic Hg2+ ions at micromolar level. An easy and cost-effective protocol for colorimetric detection of potentially hazardous Hg2+ ions was developed through sonochemical-assisted eco-friendly synthesized silver nanoparticles (AgNPs). The AgNPs were prepared using the aqueous extract of avocado (AV) seed at room temperature. UV–visible spectroscopy revealed the formation of AV-AgNPs with a narrow surface plasmon resonance (SPR) band at 417 nm. FTIR analysis exposed the capping and stabilisation of phytoconstituents on the surface of AV-AgNPs. The average particle size was determined using a DLS profile to be 119 nm. FE-SEM images were revealed the spherical morphology of AV-AgNPs. In EDX spectra, AV-AgNPs exhibited a characteristic peak of Ag at ∼ 3 keV. Further, the unmodified AV-AgNPs were evaluated for colorimetric detection of different metal ions in aqueous medium. Surprisingly, these unmodified AV-AgNPs showed a good colorimetric selective sensing response towards Hg2+ ions. The colour of AV-AgNPs was changed from brown to colourless and accompanying the disappearance of the SPR band with blue shift. There was no distinct colour change and disappearance of SPR band for the other investigated metal ions. The detection limit of AV-AgNPs probe towards Hg2+ was 3.0 × 10−4 M. The redox reaction between AgNPs and Hg2+ ions could be the basis for a selective sensing mechanism. The AV-AgNPs probe showed a good linear response in the range of 25–200 μM towards Hg2+ with R2 value 0.9914. The exceptional performance of unmodified green synthesized AV-AgNPs suggested a very promising probe for on-site detection of Hg2+ in water sample. [ABSTRACT FROM AUTHOR]

A self-assembled monolayer (SAM) of 4-aminothiophenol (4-ATP) was formed on copper surface which was characterized using cyclic voltammetry, Fourier transform infrared spectroscopy, and Raman spectroscopic techniques. The surface morphology of the monolayer was examined by scanning electron microscopy. The anticorrosive property of the SAM was investigated using electrochemical impedance spectroscopy and polarization studies. The electrochemical measurements showed that the inhibition efficiency increased with the immersion time of copper in ethanolic solution of 4-ATP in 3.5% NaCl. The significant corrosion protection efficiency of SAM could be due to the compact and dense monolayer on metallic surfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] • Silver nanoparticles were synthesised using Persea americana seed extract in an eco-friendly approach. • The presence of biomolecules such as phenols, triterpenes, phytosterols, flavonoids, and carbohydrates in the extract were identified by a standard phytochemical analysis. • The formation of Persea americana -derived silver nanoparticles were confirmed by a surface plasmon resonance band at 430 nm in UV–Visible spectroscopy. • The as-synthesized green inspired silver nanoparticles were showed good antibacterial, antifungal and antioxidant activities. This study aims to perform a green synthesis of silver nanoparticles (AgNPs) using Persea americana seed. UV–vis, FTIR, XRD, DLS, FE-SEM, EDX and TGA were used for characterizing the AgNPs. The production of AgNPs was primarily observed by change in colour from yellow to reddish-brown and then confirmed by SPR band at 430 nm in UV-vis spectral analysis. FTIR analysis exposed the role of phytoconstituents in the P. americana seed extract as bioreductant, stabilizing and capping agent. In XRD pattern, the major peaks correspond to the planes (2 1 0), (1 1 1), (2 0 0), (2 2 0) (3 1 1) and (2 2 2) which revealed the FCC crystal structure of AgNPs. The average particle size and zeta potential value determined using DLS were found to be 62 nm and − 16.3 mV, respectively. The negative value of zeta potential provides the repulsive force as electrostatic stabilization of AgNPs. FE-SEM images were evidenced the spherical morphology and EDX spectrum revealed a characteristic metallic silver peak at 3.0 keV. We investigated the antibacterial activity of AgNPs against S. pyogenes, P. acnes, E. coli and P. aeruginosa. Our results showed that AgNPs (5.0 mg/mL) were more effective at inhibiting S. pyogenes , P. acnes and E. coli with zone of inhibition of 17.5 ± 0.70, 16.75 ± 1.06 and 9.75 ± 1.06 mm, respectively. We also found that AgNPs had antifungal activity against A. fumigatus. The diffusion of AgNPs into cell wall of microorganism causing morphological distortions and disruption of respiratory functions, which in turn lead to cell death. The synthesized AgNPs have good antioxidant activity with an IC 50 and DPPH radical scavenging rate of 57.67 μg/mL and 70.89 %, respectively. The current study will lead to new antibacterial, antifungal and antioxidant agents in the fields of biomedicine. [ABSTRACT FROM AUTHOR]

The present work deals with the electrochemical synthesis of poly-4-methyl-3-mercapto-1,2,4-triazole (p-MMTA)/TiO composite on metallic copper to evaluate its corrosion protection. The composite was characterized by FT-IR, cyclic voltammetry, X-ray diffraction and energy dispersive X-ray analysis. The distribution of inorganic particles in the polymeric matrix was evidenced from the scanning electron microscopic studies. The corrosion performance of composite coating was evaluated by electrochemical impedance spectroscopy and Tafel polarization measurements in 3.5 % NaCl medium. The p-MMTA/TiO composite showed an excellent corrosion protection ability, which was evidenced from the results of electrochemical measurements. The enhanced ability could be due to the barrier effect of composite coatings against corrosive species and also due to the synergistic effect between organic polymer and inorganic particles. [ABSTRACT FROM AUTHOR]

Abstract: The self-assembled monolayer (SAM) of 3-amino-5-mercapto-1,2,4-triazole (AMTa) was formed on a copper surface and characterized using cyclic voltammetry, Fourier Transform Infra-red spectroscopy and scanning electron microscopy. Quantum chemical calculations suggested the stronger interaction between AMTa and copper. The protection ability of SAM has been evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization measurements. The formed monolayer showed significant protection ability in 1% NaCl medium. The enhanced corrosion protection ability could be due to the compact film structure which blocks the electron transfer from the solution to AMTa monolayer modified copper substrate. [Copyright &y& Elsevier]