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A novel and convenient approach for the fabrication of vinyl functionalized multiwalled carbon nanotube (MWCNT) as a sorbent for organic pollutant is described in this article. In this method, the purified MWCNT is functionalized via a non-covalent strategy using 9-vinyl anthracene, fluorescent active species. The synthesised nanotube was characterised using various techniques such as Fourier transform infrared spectroscopy (FT-IR), UV-Vis. spectroscopic analysis, scanning electron microscopy (SEM), X-ray diffraction technique (XRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM) and Raman spectroscopy. Effects of concentration, pH and time for the functionalization of MWCNTs were investigated through photoluminescence (PL) studies. The resulting vinyl functionalized MWCNT will act as a promising adsorbent for organic pollutants like p-chlorobenzoic acid.

A green protocol for the preparation of silver nanoparticles using the leaf, fruit and stem extracts of Hyptis capitata, one of the commonly found plants in the tropics.

Electrospinning is always a fascinating fiber formation technique in the material science world. The characteristic properties and functionalities of the electrospun nanofibers keep them attractive always and everywhere. Here PMMA electrospun nanofibers with 60–150 nm are produced and characterised by various characterisation techniques. Gold nanoparticles (AuNPs) incorporated electrospun PMMA nanofibers are produced by dispersion of the prepared PMMA nanofibers in colloidal AuNPs. The homogenous distribution of AuNPs on PMMA fiber surface is proved by TEM, FESEM, XRD, FTIR etc. and the optical characterisations are done by UV and PL analyses. PL spectra of the AuNPs incorporated PMMA nanofibers showed the characteristic absorptions of both PMMA and AuNPs in the visible region which shows the successful incorporation of the gold nanoparticles to PMMA nanofibers. The PL spectrum shows a characteristic blue shift in peak position with increase in excitation wavelength. The AuNPs incorporated PMMA nanofibers show enhanced photoluminescence than pure PMMA nanofibers which points to the host matrix nature of PMMA to noble metal nanoparticles like AuNPs.

Computational strategies have been employed to investigate the influence of the nature of monomers and cross-linker in order to design three dimensional imprinted polymers with selective recognition sites for L-phenylalanine benzyl ester (L-PABE) molecule. Here, computational chemistry methods were applied to screen the molar quantity of functional monomers that interact with one mole of the template molecule. Effects of the nature of functional monomer, cross-linker, and molar ratio were determined computationally using density functional calculations with B3LYP functional and generic 6–31G basis set. Methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) were used as the functional monomer and crosslinking agent, respectively. L-PABE imprinted polymer layered on multiwalled carbon nanotube (MWCNT) and conventional bulk MIP were synthesised and characterized as well. To investigate the influence of pre-organization of binding sites on the selectivity of L-PABE, respective non-imprinted polymers were also synthesised. MWCNT-MIPs and MIPs exhibited the highest adsorption capacity towards L-PABE. The synthesized polymers revealed characteristic adsorption features and selectivity towards L-PABE in comparison with those of its enantiomer analogues.

A novel chiral sorbent for l -phenylalanine benzyl ester (L-PABE) is designed computationally by investigating the influence of the nature of template-monomer mole ratio and cross-linker. Density Functional calculations with B3LYP functional and generic 6-31G basis set was used as a computational tool with a photo-switchable azo-benzene derivative, 4-[(4-methacryloyloxy)phenylazo]benzoic acid (MPABA) as the functional monomer. 1:4 mol ratio of L-PABE and MPABA was chosen as the best imprinting ratio and N, N-ethylene bismethacrylamide (EBMAA) was used as the crosslinking agent. L-PABE imprinted polymer layered on multiwalled carbon nanotube (MWCNT) and conventional bulk MIP were also synthesized and characterized to investigate the influence of pre-organization of binding sites on the selectivity of L-PABE, respective non-imprinted polymers were also synthesized. MWCNT-MIPs and MIPs exhibit the largest adsorption capacity towards L-PABE. The synthesized polymers reveal characteristic adsorption features and selectivity towards L-PABE in comparison with its enantiomer analogues. Photo-regulated uptake and release studies of MWCNT-MIP and MIP on L-PABE were also done to determine the photo-switching reversibility of functional monomer.

Molecularly imprinted polymer (MIP) is a polymer competent of mimicking selective binding of target or template molecule, which is characteristic of enzyme and antibodies. MIP has a wide range of applications in various fields of science and can be used as a sensor, catalyst, drug delivery component, etc. To overcome some demerits of MIP, the process of formation of imprinting cavity was carried out by nanoimprinting materials, which enables the imprinting technique to create more effective recognition sites than those obtained by traditional approaches. Here, in this article, we described a brief account of various discoveries happened in titanium dioxide–based molecularly imprinted polymeric system that shows a wide variety of chemical applications. The intention of this article is to provide comprehensive knowledge and information to all researchers who are interested in exploiting molecular imprinting technology toward the rational design of various chemical sensors operating on different transduction principles, ranging from electrochemical to piezoelectric, being used for the detection of different template molecules as they pose considerable impact on the understanding of the origin of life and all processes that occur in living organisms.

Attempts have been made to investigate the feasibility of fabricating an enantiomeric sensor for the selective and specific detection of D-mandelic acid (D-MA) layered on vinyl-functionalized multiwalled carbon nanotubes (vinyl-MWCNT) using an exploratory technique of molecular imprinting. Here computational strategies have been applied to design a composite of molecular imprinted polymers using D-MA, exhibiting a significant role in pharmaceutical synthetic industry, as a template molecule. Effects of functional monomer, cross-linker and template-monomer mole ratio were determined computationally using density functional theory calculations with B3LYP functional and generic 6-31G (d,p) basis set. The enantioselective sensor is fabricated on a platinum working electrode using imprinted and non-imprinted polymers and electrochemical features are investigated using electrochemical measurements such as cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy. Several parameters including scan rate, pH of the buffer and ratio of template and functional monomer are investigated and optimized during sensor preparation. For a better assessment, non-imprinted polymer on MWCNT, which is designated as MWCNT-NIP, was fabricated using the same method, only without adding the D-MA molecule during the polymerization process. Characterizations techniques like Fourier transform infrared spectroscopy, X-ray diffraction technique, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy were used to analyze the fabricated polymer composites.

Recent advancement in deep learning has applied to solve various complex problems ranging from big data analytic to computer vision and human-level control. One among them is the deepfake technology which becomes a real threat to privacy, democracy, and national security. Deepfake is hyper-realistic digitally manipulated videos to depict people saying and doing things that never actually happened. This technology has been used in many fields in film industries for recreating videos without re-shooting, awareness video generation such as creating voices of those who have lost theirs or updating episodes of movies without re-shooting them at very low cost. This technology has many harmful usages in social media, pornographic sites, etc. to deface peoples which largely dominate the positive side of this application of deep learning. Also, the creation and spreading of these videos are increasing rapidly along all fields of media files. Therefore, it is very much important to develop efficient tools that can automatically detect the deepfake in these videos and thus reduce the public harm caused by such videos. In the early stages of deepfake detection, traditional technologies like signal processing, image processing, lip-syncing, etc were used but this provides very little accuracy when combined with the recent technologies of deep learning. So, here a system is proposed that can automatically detect the deepfake in media files such as images, videos, and audios. This uses an image processing approaches combined with deep learning which detects the inconsistency that exists in fake media.

Inhibition of mild steel corrosion in 1N hydrochloric acid with 4-amino-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one (AMTDT) and (4-amino-4H-1,2,4-triazole-3,5-diyl) dimethanol (ATD) was investigated by polarization (Tafel), electrochemical impedance (EIS), adsorption and computational calculations at 27 °C. The mixed type inhibitor property of these inhibitor molecules was investigated by potentiodynamic polarization studies. It was revealed that the effectiveness of inhibition is influenced by several factors such as the nature and state of the metal surface, the type of corrosive medium, the structure of the chemical compound used as inhibitor and molecular electronic parameters. Obvious correlations were found between corrosion inhibition efficiency and some quantum chemical parameters. Monte Carlo simulations were applied to search for the most stable configuration and adsorption energy for the interaction of inhibitors on Fe (1 1 1) interface. Calculated results indicated that the difference in inhibition efficiencies between the compounds can be clearly explained in terms of frontier molecular orbital theory.

In the present article, we fabricated an artificial sorbents of D-mandelic acid (D-MA) on vinyl functionalized multiwalled carbon nanotube (MWCNT) by molecular imprinting technology. Here molecular imprinted polymers (MIPs) were tailored by D-MA as a template molecule on the surface of the vinyl functionalized MWCNT with 4-vinyl pyridine (4-VP) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent and 2,2′-azo-bis-isobutyronitrile (AIBN) as the initiatorvia a thermal polymerization technique. For better evaluation, blank polymer (MWCNT-NIP) was prepared by the same procedure, only without using the template molecule in the polymerization process. To get a better knowledge of the role of MWCNT on chiral recognition, D-MA imprinted and non-imprinted polymers without MWCNT were also prepared and analysed. Fourier transform infrared spectra (FT-IR), X-ray diffraction technique (XRD), Thermogravimetric analysis (TGA), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) were used to characterize the composite structure, morphology and determine the grafted MIP quantities in the composite. Selective adsorption and specific chiral recognition of synthesised polymers were examined using the theory of kinetics and thermodynamics. The resulting MWCNT-MIP demonstrated favorable selectivity, good stability and a higher adsorption capacity for the template particle compared to products created by bulk polymerization. The thermodynamic studies revealed that the adsorption was controlled by enthalpy and that MWCNT-MIPs had higher enthalpy and entropy than conventional polymers which contributed to the specific recognition of MWCNT-MIPs. D-MA adsorption on MWCNT-MIP is in good agreement with Langmuir adsorption isotherm and kinetics obey second order rate expression with rate constant k2 = 0.1482 mol−1 min −1. Kinetic correlation indicated that there was fast and selective adsorption equilibrium for D-MA molecules in MWCNT-MIPs happen because of the homogenous binding sites of template molecules on the surface of nanotubes.

The present work is aimed to the fabrication of enantioselective sorbent and sensor for the selective and specific recognition of L-phenylalanine benzyl ester (L-PABE) template molecule in photo-responsive molecularly imprinted polymer (PR-MIP). Here a photo-switchable azo-benzene derivative, 4-[(4-methacryloyloxy)phenylazo]benzoic acid (MPABA) is synthesised and used as the functional monomer. Composites of multiwalled carbon nanotubes (MWCNTs) and imprinted polymer were prepared using 1:4 mol imprinting ratio of L-PABE and MPABA and N,N-ethylene bismethacrylamide (EBMAA) as the crosslinking agent. Conventional bulk MIP and their respective non-imprinted polymers were also synthesised and characterized to investigate the influence of pre-organization of binding sites on the selectivity of L-PABE. The enantioselective sensor is fabricated on platinum working electrode using imprinted and non-imprinted polymers and their electrochemical measurements are investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and elctrochemical impendence spectroscopy (EIS). The platinum modified sensors possess a limit of detection and limit of quantification as 0.2086 μmol L−1 and 0.6953 μmol L−1 respectively. MWCNT-MIPs and MIPs exhibit the largest adsorption capacity towards L-PABE. The synthesised polymers reveal characteristic adsorption features and selectivity towards L-PABE in comparison with its enantiomer analogues. Photo-regulated uptake and release studies of MWCNT-MIP and MIP on L-PABE were also done to determine the photoswitching reversibility of functional monomer.

Coatings tailored to corrosion protection of metallic substrates are of the utmost relevance to ensure reliability and long-term performance of coated parts as well as the product value of the coated materials. Presently, there is a strong emphasis on the development of advanced functional and smart coatings for corrosion protection in different technological applications. This work aimed to develop a novel coating based on chitosan and PVA to evaluate its corrosion inhibition effect on mild steel. Chitosan/PVA films were coated on mild steel by dip coating technique. Sol–gel protective coatings have shown excellent chemical stability, oxidation control and enhanced corrosion resistance for metal substrates. Further, the sol–gel method is an environmentally friendly technique of surface protection which has traditionally been used for increasing corrosion resistance of metals. Films so formed were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), the thermal property of the chitosan–PVA film was examined by differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Corrosion protection behavior of these coated mild steel substrates in 0.1 N HCl solutions was evaluated by potentiodynamic polarization studies (Tafel), linear polarization studies (LPR), and electrochemical impedance spectroscopy studies (EIS). The experimental results showed that the chitosan/PVA composite coatings were superior to pure chitosan in corrosion protection. EIS measurements and Tafel polarization method have proven that corrosion resistance of mild steel in 0.1 N HCl solutions, increases with increasing the number of layers of chitosan/PVA films. The results indicated that the polymer film adhered to the mild steel surface and inhibited the mild steel corrosion in 0.1 N HCl.

This paper presents a chat application that make use of speech as interaction mode between users in their mother tongue. This system is based on Machine Translation (MT) which automatically translates a sentence from one language to other. Now-a-days, Chat has become increasingly important as an effective means to communicate in social networks. But in existing personal chat systems, chat services are text-based only. To circumvent this issue, innovative, practical XMPP-based chat system architecture is proposed in this paper that creates a Speech based chat services by integrating state-of-the-art technologies like Automatic Speech Recognition (ASR), Text to Speech (TTS) and Machine Translation (MT). The proposed system eliminates the need to have a common language for chat communication. In this chat system the user speak in their own language after selecting the language of their comfort. The audio will be recognized in real time. The text is translated to the language opted by end user and the system synthesizes it. Here, we discuss an interface prototype that can overcome the language barrier to some extent.

The recent development in text to speech has been switched to concatenative synthesis, either using original speech segments or parametric synthesis. The former TTS system gives a better quality output since they use the original speech segment for concatenation. There are a number of different other techniques for speech generation like PSOLA, TDPSOLA, EMBROLA etc. This paper describes the development and implementation of concatenative based system based on Epoch Synchronous Non Overlap and Add (ESNOLA) technique for Malayalam in android platform. The TTS uses diphone like segments (partneme) as the basic units for concatenation. The database contain 1500 partnemes, which are used for generating speech for unlimited domain text. The paper also briefs about the implementation of Malayalam TTS, the database generation, the modification done for android platform, the database access and handling Malayalam character display in android platform, the support provided in the TTS app for displaying characters with proper rendering. The app support android latest versions upto android 4.2. The design for Newsreader, an application using android is also discussed in this paper. The TTS gives a Mean Opinion Score (MOS) of 3.2 in the perceptual test..

India is home to about 1600 languages. Less than 5% of this population is English literate. A consortium effort on developing a common framework to build text-to-speech synthesis (TTS) in various Indian languages has already been realized. In this paper, we propose a parallel effort to integrate the various TTS systems developed into various applications. These applications are primarily aimed at bringing the marginalized sections of Indian society into the main stream. The applications integrated include: i) screen readers for the visually challenged on desktop platforms ii) web-based plug-in to read highlighted text for the language challenged iii) integration of TTS with optical character recognition systems iv) various applications for the Android platform v) On-line test and tutorial for visually challenged and vi) conversion of gesture to speech for persons with cerebral palsy. The performance of the integrated systems have been extensively tested by visually challenged persons for the last three years. About 180 students have learnt to use the Office Suite, Internet and e-mail over the last 3 years.

This paper describes the development of optimized multiunit speech database for a high quality concatenative TTS System. The core engine used for the development of Text to speech is the open source FESTIVAL engine and is tested for Malayalam language. The optimal text selection algorithm selects the optimal text, ensuring the maximum coverage of units without discarding entire low frequency units. In this work we created a multiunit database with syllable as the highest unit, ensuring the coverage of all CV-VC units, and phones.