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Here, diazo coupling reaction was imparted on chemically inert lignin isolated from natural resources. Activated lignin was coupled with the diazotised aniline, m-nitroaniline, p-nitroaniline-, and p-anisidine gives organic pigments.

The continuous increase in particle size of pigments confirms addition of diazotised salt to lignin by coupling reaction. Further, the dispersing ability of these coloured pigments were exploited in polymer matrix. Epoxy-polyamine cross linking system was doped with difference percentage of pigments and coated on mild steel metal surface. The morphology of these composites was understood by SEM, particle size, differential scanning calorimeter and thermo gravimetric analysis.

The synthesised organic pigments were characterised by FT-IR, ¹H NMR and UV-visible spectroscopy. It was observed that hiding power of aniline- and m-nitroaniline–based azo pigments was more than p-nitroaniline- and p-anisidine–based azo pigments. Thermal properties as well as water contact angles of coatings were improved with pigment concentration. The chemical resistivity of coating was observed to be improved with the increasing % of lignin-based azo pigment.

Lignin-based azo pigment has great potential to replace metal oxide pigment and provide strategy for utilisation of lingo-cellulosic biowaste material.

The purpose of this study is to develop luminescence sensors for the detection of nitroaromatic compounds (NACs) and metal ions to protect human health and prevent environmental pollution.

The composition and morphology of Eu-metal-organic frameworks (MOF) (1) were well characterized by powder X-ray diffraction, elemental analyses, Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy and scanning electron microscopy. The emission spectrum displays that 1 has significant characteristic emission bands of Eu(III) ions. The authors further investigated the fluorescence sensing performances of 1 to NACs and metal ions.

The results show that Eu-MOF (1) exhibits significant fluorescence quenching effect toward p-nitroaniline and Fe³⁺ ions with good stability and recyclability. This means that 1 can be used as a multifunctional sensing material for the detection of p-nitroaniline and Fe³⁺ ions.

The authors have successfully synthesized a fluorescence Eu-based sensing material under hydrothermal conditions. In addition, the fluorescence property and sensing performances for detecting NACs and metal ions were studied. The results suggest that 1 has highly selective fluorescence quenching toward p-nitroaniline and Fe³⁺ ions with not only high sensitivity and selectivity but also excellent stability and recyclability. Furthermore, this study has confirmed that the multifunctional MOF material is very useful in environment pollutants’ detection and monitoring.

To study the effects of isomers of organic compounds such as phenylenediamine, toluidine and nitroaniline as inhibitors for the corrosion of carbon steel in sulfuric acid.

Standard methods have been adopted in this study such as weight loss, polarization tests, impedance measurements and hydrogen permeation studies to find out the corrosion behavior of carbon steel in sulfuric acid with and without inhibitors.

All the selected isomers inhibited the corrosion. The best performance was found in ortho‐phenylenediamine when compared with other inhibitors under study.

It clearly shows the effect of isomers of phenylenediamine, toluidine and nitroaniline. The method of study may be applicable to find out the performance of other isomers of organic compounds. As these isomers behave as good inhibitors in sulfuric acid, these may be tried as inhibitors in other acids. Hence, this study is useful to academics and researchers in the field of corrosion science and engineering.

Due to the constituent nitrogen atom of the amino group, amines have been extensively used as inhibitors of metallic corrosion. This article reviews the reported uses of aniline and related aromatic amines as corrosion inhibitors.

The synthesis and chemistry of nitrogen heterocyclic azo compounds have been extensively studied. Many derivatives of this type were proved to be excellent dyes. Presents a systematic and comprehensive survey of all recently synthesised nitrogen heterocyclic azo dyes according to dyeing methods.

The purpose of this paper is to synthesise some disperse dyes containing a reactive group and study their applications on polyamide and wool printing by heat transfer and screen printing.

To prepare these dyes, arylhydrazones of acetylacetone were reacted with cyanothioacetamide in boiling ethanolic sodium ethoxide. The resultant salt was collected by filtration and dried, then the salt was dissolved in ethanol and reacted with chloroacetylchloride with stirring for 3 h, where chloroacetylechloride was added dropwise. The final precipitated product was collected by filtration and crystallised with an appropriate solvent. These prepared dyes were used to print polyamide and wool fabrics by using synthetic thickener in the printing paste for all techniques.

The structure of the synthesised dyes were established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (MS, IR and ¹H‐NMR). The suitability of the prepared dyestuffs for either heat transfer printing or traditional printing on nylon 6 and wool fabrics was investigated. The prints obtained from dyes possess high‐colour strength as well as excellent overall fastness properties.

The synthesised heterocyclic reactive disperse azo dyes were prepared from the reaction of arylhydrazones of acetylacetone and thiocyanoacetamide to form the corresponding pyridinethione salts which underwent further reaction with chloroacetylchloride. The obtained dyes were utilised in preparing a paste for polyamide and wool fabric printing. In addition, both of the variation of the substituents on the synthesised dyes and the fastness properties were also studied.

The synthesis and use of reactive disperse dyes provide practical solution to over come the low fastness on polyamide and wool, when they are printed with disperse dyes only.

The result of the work aimed to define the scope and limitation of the authors' procedures for the synthesis of novel reactive disperse azo dyes to improve the low‐fastness properties of polyamide and wool, the dyes were synthesised in a simple way.

STEEL Anti‐corrosive carbonate layer. Calcium bicarbonate, which is present in virtually any natural water, suppresses the corrosion of steel if it is allowed to form—together with corrosion products—a coherent adhesive layer of calcium carbonate on the steel surface. The deposition of such a layer depends on the flow and the temperature of the water as well as on the concentration of calcium bicarbonate. Recent Czechoslovak work has been concerned with the use of radioactive calcium‐45 in the study of the influence of these factors on the formation of protective calcium‐carbonate layers in cold and warm water with low calcium bicarbonate content.

This paper aims to evaluate the corrosion inhibition capacities of synthesized compounds 1-(2-pyridinyl)-2-(o, m-, p-hydroxyphenyl) benzimidazoles in API 5L X52 steel/HCl 1M corrosion system.

Electrochemical impedance spectroscopy technique was used.

The studies determined that under stagnant conditions, the durability and efficiency were maintained over 80 per cent for up to 500 h of immersion, while the residence time started to decrease after 150 h at the best inhibitor concentration (150 ppm).

This work may help to attenuate corrosion problems in the petroleum industry.

It is the first time that 1-(2-pyridiniy)-2-(o-, m-, p-hydroxyphenyl) benzimidazoles were evaluated as corrosion inhibitors.

Three series of azo dye systems are considered, namely, 5‐oxo‐2‐pyrazoline azo dye systems 9 a‐d,1‐oxo‐pyrazolo pyrazole azo dye systems 10 a, b, c, e, 11 a, b, c, e, 12 a, b, c, e, 13 a‐d and 6‐oxo‐pyranopyrzole azo dye systems 14 a‐d. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the pyrazole dye systems are investigated. The structural effects of the polyfunctionally substituted pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are also discussed. The data of these studies are listed. Colour shades of the synthesized dyes on nylon and acetate fabrics are indicated.

A new series of printing inks that satisfy non‐absorbent substrates, namely, metals and metal foils has been formulated. The suggested ink formulations are well adapted for the Lithographic and Flexographic Printing Processes. The inks are subjected to different testings and controllings to fulfill the requirements of printers in the graphic trade.