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The paper introduces a new method for single step synthesis of copper phthalocyanine green pigment using microwave irradiation to activate C−H bonds on the aromatic rings that are possible by creation of chlorine radicals. The aims of this study are to investigate the possibility of high-efficiency product reaction, removing acidic wastewater, time optimization, and maximizing number of chlorine on aromatic rings.

The paper presents a new synthesis technique, which does not have the problems of the conventional methods. Microwave irradiation is used as a chemical reaction initiator by creation of chlorine radicals in saturated aqueous solution of sodium chloride and C−H bond activation on aromatic rings. The approach yields to a high quality of product, uniform particle size distribution, high efficiency and an environmental friendly procedure.

The paper introduces the use of suitable materials and water solvents in chemical reactions under microwave radiation at low temperatures. This shows that the microwave irradiation activates C−H bonds on aromatic rings and creates chlorine radicals at the same time, which results in relatively fast reaction of synthesis copper phthalocyanine green.

The ammonium molybdate catalyst, which is used in this method, should be weighed carefully. The effects of transition metals on chemical reactions in the presence of microwave irradiation can also be chlorinated other unsaturated bonds.

The method develops a simple and practical solution to improve the synthesis of phthalocyanine green pigment.

The synthesis method of copper phthalocyanine green pigment is novel. CuPhcCl₁₆ has numerous applications in industrial.

The purpose of this study is to determine the physicochemical and rheological parameters of Albizia lebbeck gum.

Physicochemical analysis was carried out using recommended methods. Gas chromatography mass spectrophotometer and Fourier transformed infra red (FTIR) analyses were carried out using their respective spectrophotometer. Scanning electron microscopy was carried out using scanning electron microscope, while rheological measurements were carried out using Ubbelohde capillary viscometer, digital Brookfield DV 1 viscometer and a rheometer.

Albizia zygia gum is an ionic gum with unique physical and chemical properties. Scanning electron micrograph revealed that the internal structure of the gum is porous with irregular molecular arrangement. Thermodynamic parameters of viscous flow indicated the existence of few inter- and intra-molecular interactions, and the attainment of transition state was linked to bond breaking. Coil overlap transition studies revealed the existence of dilute and concentrated regimes. The viscosity of the gum was also found to decrease with decrease in the charge of cation (such that Al3+ > Ca2+ > K+) and with increase in ionic strength.

The paper provided information on physicochemical and rheological characteristics/behaviour of Albizia zygia gum, of Nigerian origin. From this information, possible application of this gum in the food and pharmaceutical industries can be deduced.

The paper is original since information concerning Albizia zygia gum of Nigerian origin are not well documented as established in the work. It also adds values on the use of Albizia zygia gum, either on its own or in combination with other gums for industrial purpose.

The aim of this study is to determine the effect of argon plasma surface modification on tribological properties of conventional ultra-high molecular weight polyethylene (UHMWPE) and vitamin E-blended UHMWPE. In previous studies, some researchers conducted a study on argon plasma surface modification of UHMWPE, but there is no study about argon plasma surface modification of VE-UHMWPE. So another objective of this paper is to compare the results for both the material groups.

UHMWPE and vitamin E-blended UHMWPE sample surfaces were modified by microwave-induced argon plasma to increase tribological properties of the materials. The modified surfaces were evaluated in terms of wettability and wear behavior. Wettability of the surfaces was determined by contact angle measurements. Wear behavior was examined by ball-on-disc wear tests under lubrication with 25 per cent bovine serum.

Argon plasma surface modification enhanced the wear resistance and surface wettability properties of conventional UHMWPE and VE-UHMWPE. Wear factor of argon plasma-treated samples reduced, but for VE-UHMWPE samples, this reduction was not as high as the conventional UHMWPE’s wear factor.

In previous studies, some researchers have studied on argon plasma surface modification of UHMWPE, but there is no study about argon plasma surface modification of VE-UHMWPE.

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

The aim of this study is to examine the effect of carbonization on the surface and its influence on heavy metal removal by water hyacinth based carbon.

Dried water hyacinth stem was used as precursor to prepare carbon based adsorbent by pyrolysis method. The adsorbent proximate (ash, volatile matter and fixed carbon) and elemental (carbon hydrogen nitrogen sulfur) composition, surface area, pore size distribution, surface chemistry was examined and compared.

The results demonstrated that through carbonization in comparison to dried water hyacinth stem, it increased the surface area (from 58.46 to 328.9 m²/g), pore volume (from 0.01 to 0.07 cc/g), pore size (from 1.44 to 7.557 Å) thus enhancing heavy metal adsorption. The metal adsorption capacity of Cd, Pb and Zn was measured and analyzed through induced coupled plasma-mass spectrometer. At metal concentration of 0.1 mg/l adsorption rate for Cd, Pb and Zn was 99% due to increased large surface area, coupled with large pore size and volume. Furthermore, the adsorbent surface hydroxyl group (OH⁻) enhanced adsorption of positively charged metal ions through electrostatic forces.

It is presumed that not only adsorption with synthetic wastewater but real wastewater samples should be examined to ascertain the viability of adsorbent for commercial application.

There are little or scanty data on the effects of carbonization on water hyacinth stem based carbon and subsequent effects on heavy metal removal in effluents.