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This paper aims to compare the inhibitive effects of polyaniline (PAni), poly(p-toluidine) and poly(aniline-co-p-toluidine) in hydrochloric acid (HCl) solution.

The electrochemical deposition of PAni, poly(p-toluidine) and poly(aniline-co-p-toluidine) on pure copper metal was studied potentiodynamically. The copolymer deposited was characterized by Fourier transform infrared (FTIR) spectroscopy, ultraviolet (UV)-visible spectroscopy and scanning electron microscopy (SEM). The corrosion inhibition studies on copper electrode were performed using electrochemical methods, viz, open circuit potential (OCP) measurements, potentiodynamic polarization scans and electrochemical impedance spectroscopy (EIS) tests, conducted in 0.1 M HCl solution.

The results of the study reveal that the copolymer of poly(aniline-co-p-toluidine) at the optimum concentration of 1 × 10−3 M has better corrosion inhibition efficiency as compared to PAni and poly(p-toluidine).

The conducting polymers are difficult to deposit on the metal surface because of their high dissolution tendency before the electropolymerization potential of the monomer is achieved.

From an environmental viewpoint, poly(aniline-co-p-toluidine) is a toxic and hazardous conducting polymer.

The paper demonstrates that poly(aniline-co-p-toluidine) showed better dispersion in different organic solvents and had higher corrosion inhibition efficiency than PAni.

Photon absorbance and reflectance are the most important parameters for the recombination of electron-hole pairs. Bandgap energy plays a vital role in photon absorption. That is, the photons with energy greater than band gap energy are absorbed. Also, the refractive index of semiconductors is responsible for photon reflection, as the surface with the highest refractive index will reflect more photons than a surface with have a low refractive index. The purpose of this paper is to improvise the absorbance and reduce the reflectance of photons on the front surface of solar cells.

Photon reflection is results in reduction in electron-hole pair generation due to the high refractive index of semiconductive materials. To overcome this problem, an Anti-reflection (AR) coating of TiO₂ and SiO₂ is undertaken on solar cells through the Sol-spin coating method. Finally, the effectiveness of the Anti-Reflection coating is scrutinized through UV Vis-Spectroscopy, which provides details regarding reflectance, absorbance and bandgap energy characteristics.

UV–visible spectroscopy was used to measure the responses from the samples. The samples responded to the ultraviolet and visible range of electromagnetic radiation perfectly. UV spectroscopy was done before and after the antireflection coating of TiO₂ and SiO₂ over the solar cell to find their corresponding extreme reflectance and absorbance values. The effects of TiO₂ and SiO₂ were evaluated from the results.

In this research work, the authors have done anti-reflection coating over solar cells with nanoparticles derived from sol-gel process. Absorbance of photons observed through diffuse reflection method.

The purpose of this paper is to highlight the one bath dyeing method for polyester/wool (PES/Wo) blend fabric with two different semi-synthetic azo dyes developed by chemically modifying the outer skin of Allium cepa.

Chemical modification is the most heartening way to impart improved properties to natural sources. Two different primary amines were coupled with the Allium cepa skin extract by a diazo coupling reaction. Synthesised dyes were characterized for their percentage yield, solubility tests, melting point, particle size analysis as well as FTIR spectroscopy and UV-Visible analysis. One bath dyeing methodology was used for application of synthesized dyes on PES/Wo blend fabric. Dyeing was performed at boil without any additional auxiliary and further percentage dye exhaustion was evaluated.

Dyeing yielded solid shade on PES/Wo blend fabric with satisfactory levelness in dyeing. The efficacy of synthesized dyes for dyeing of PES/Wo fabric was studied by wash, rub, light and sublimation fastness properties, which are in good agreement with commercial requirements. The antimicrobial activity of the synthesized dyes shows excellent activity in dye powder form (AATCC 147 test method) as well as on dyed fabrics (AATCC 100 test method).

Present research work is a first successful attempt to dye PES/Wo blend fabric with semi-synthetic azo dyes in single bath at boil. Such approach facilitates minimum consumption of energy, cost and time.

Use of highly dye doped nano composite for organic pollutant degradation.

One-pot synthesis of titanium nano-particles were carried out in the presence of N719 dye.

High dye doping and exceptional dye degradation efficiency was observed. Within 25 min, 99 per cent of methylene blue was removed from waste water.

A novel one-pot synthesis of the composite was introduced.

A graft copolymer (PBW-g-PAM) of Moringa seed was prepared. The phosphate buffer washed seed powder and polyacrylamide were reacted, using ceric ion initiator. The grafted copolymer was tested for its efficiency for metal removal (Cr-VI) from tannery effluent and for color removal from textile effluent using standard spectroscopic methods. The paper aims to discuss these issues.

The PBW-g-PAM was prepared by standard method and characterized by FT-IR, SEM, UV-vis, XRD and DSC/TGA analyses.

The effects of PBW-g-PAM dose, contact time and pH on percent removal of Cr-VI and dye color, have been reported.

The efficiency of metal removal was shown to be 99 per cent in just 15 min. Similar results were obtained for efficient color removal from textile effluents. It is for the first time that graft polymer of Moringa seed has been used for metal and color removal.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

The purpose of this paper is to evaluate the corrosion inhibition potential of Calotropis procera in sulphuric acid medium on mild steel with a view to developing green corrosion inhibitors.

Extract of the C. procera was studied for its corrosion inhibitive effect by weight loss, electrochemical, SEM and UV methods. Using weight loss measurement data, mechanism of inhibitive action is probed by fitting in adsorption isotherm.

C. procera has been found to show significant corrosion inhibitive effect in sulphuric acid medium on mild steel. Inhibition is through adsorption of the phytoconstituents on mild steel following Tempkin adsorption isotherm. The results of ac impedance and polarization studies correlate well with the weight loss studies.

The plant has been investigated for the first time for its corrosion inhibitive effect. The effect has been studied by proven methods. This green inhibitor can find use in the inhibition of corrosion in industries where mild steel is used as a material of choice for the fabrication of machinery.

Nutraceuticals which have nutritional and therapeutic properties cannot be consumed directly due to their off flavor hence, a carrier in the form of microcapsules may be a better option for their application in foods. The purpose of this paper is to describe the preparation of nutraceutical barriers as microcapsulels.

Nutraceutical concentrates were isolated using methanol from sesame (Sesamum indicum), linseeds (Linum usitatissimum), black mustard (Brassica napus), yellow mustard (Brassica compestris) and niger seeds (Guizotai abyssinica) employing established protocol. These concentrates were further purified, enriching active ingredients using column chromatography to remove hydrocarbons, gums and other non‐polar inactive materials. These purified concentrates were subjected for sesamol, tocopherol, polyphenol and β‐carotene estimations. Subsequently, they were converted into microcapsules using spray drying, inclusion complexation and liposomal entrapment techniques.

The scanning electron microscope image of the spray‐dried nutraceutical concentrates isolated from sesame seeds showed that microcapsules were spherical in shape with 5‐25 μm in diameter with mean particle size of 10 μm with smooth outer surface and bee net like inner structure which yielded a uniform and smooth wall of microcapsules. Thickness of the wall was found to be 2‐5 μm. Sesamol, tocopherol, polyphenol and β‐carotene found to be ranging between 35,600 and 0; 14,520 and 890; 35,800 and 5,900 and 890 and 290 ppm. The encapsulation efficiency of spray drying, inclusion complexation and liposomal entrapment was 75.5, 54 and 58 percent, respectively, which considered to be good efficiency. The moisture content of the powders were found to be between 4 and 5 percent. The difference between the highest and the lowest moisture content at each relative humidity was about 0.5 percent. The percent nutraceutical concentrate adhering to the surface of granules during above encapsulation ranged between 1 and 5.5 percent.

Much work has been done on the nutraceuticals but information is very scarce on nutraceutical carriers. To carry the nutraceuticals to the site of delivery in intact form, nutraceutical carriers are inevitable. This paper describes how to prepare nutraceutical carriers as microcapsules by using spray drying, complexation and liposome entrapment procedures to obtain stable granules which can be used in food applications.

This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra.

6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed.

Ultra violet-visible UV-vis absorption spectra of the dyes didn’t show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base.

The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties.

The purpose of this paper is to synthesize Cr-ZSM-5 using hydrothermal synthesis in acidic fluoride medium and the investigation of its catalytic performance in heterogeneous oxidation of 2-mercaptobenzothiazole in the presence of H₂O₂.

The framework was characterized by chemical composition, FT-IR, UV-visible spectroscopy, N₂ adsorption (BET), and diffraction x-ray (DRX). FT-IR spectroscopy shows the characteristic band of Si-O-Cr linkage around 960-990 cm⁻¹ and bands around 688-690 and 627 cm⁻¹, indicating the presence of extraframework chromium oxide. UV spectra show a shoulder around 244-257 and bands around 360-380 nm, assigning the tetrahedral coordinated environment in (O²⁻=Cr⁶⁺) − (Cr⁵⁺-O⁻¹), charge transfer transition state (CT) of isolated Cr (VI) inside the structure of Cr-ZSM-5.

The catalytic degradation of 2-mercaptobenzothiazole by H₂O₂ heterogenous oxidation using catalyst Cr-ZSM-5 showed the formation of bis (benzothiazoyl) disulfide with 95 percent yield.

The application of this process in the environment (catalysis, adsorption, and degradation of organic compounds).