Experimental Investigation of Wire-EDM Machining of Low Conductive Al-SiC-TiC Metal Matrix Composite

The application of metal matrix composites (Al-SiC-TiC) in aerospace and defense industries have surged in the areas of hull safety, aviation fins, and closure units. The close to ideal solution for generating powdered mixture availing ball milling, for processing of a metal matrix composite of size 24 × 24 × 5.95 cm3 and composition of 75% Al, 10% SiC, and 10% TiC weight composition is 10:1 ball weight ratio, ball size of 8 mm, rotation speed of 250 rpm, and milling time of 4 h. The powdered mixture is compressed to pellet, sintered for two hours, and further silver coated in a physical vapor deposition setup to surge its electrical conductivity for ease of material removal. To obtain a perfect fit and finish, wire electrical discharge machining cycle has been carried out to machine the component under deionized water and oil + wax + paraffin dielectric mediums in 8 A peak current, 0.45 µs pulse on time, and 45 pulse off time as close to ideal solution, obtained by the technique for the order of preference by similarity to the ideal solution (TOPSIS) analysis. A surge is ascertained in kerf width, material removal rate, and surface roughness in oil + wax + paraffin environment in correlation with deionized water by 0.99–12.78%, 0.18–33.97%, and 2.15–36.86% respectively. The surface morphological study indicates a 32.28%, 42.57%, and 45.73% surge in residual compressive stress, surface roughness and corrosion resistance in oil + wax + paraffin dielectric medium in correlation to deionized water.

Influence of pelleting on microbiological and mycotoxical correctness of feed mixtures with bentonite supplement

Influence of pelleting calf feed mixtures supplemented with bentoni on microbiological and mycotoxicological properties was investigated. Microbiological and mycotoxicological quality was investigated at the production day (day 0) and after 45 days of storage. Total count of microorganisms in the pelleted mixture, at the day 0 (280.000/g), was several times lower than in the powdered mixture (2.000.000/g). Similar results were obtained at day 45 when the total number of microorganisms in the pelleted mixture was 270.000/g and 1.800.000/g in the powdered mixture. Number of yeasts and molds at the production day in the pelleted mixture was 650/g, and in the powdered mixture it was 27.000/g. Similar results were obtained 45 days later when the number of yeasts and molds in the pelleted mixture was 540/g, and 16.000/g in the powdered mixture. There were 6 species identified in the pelleted mixture, and 9 species in the powdered mixture at the day of production. Similar mold species ratio in the pelleted (11) and powdered mixture (13) was found at day 45. In the examined samples representatives of Fusarium genus - F. subglutinans i F. verticillioides dominated. Number of sultite-redzcing clostridia in the mixtures, in both observed periods, was similar (below 1000/g of sample). By mycotoxicological analysis of mixtures at the production day, only trichotecene (T-2 toxin) presence was found in amount of 0,337 mg/kg. The applied technological procedure of pelleting with bentonite supplement, had positive influence on the improvement of microbiological and toxicological properties of mixture.

Rapid and Easy Identification of Illicium verum Hook. f. and Its Adulterant Illicium anisatum Linn. by Fluorescent Microscopy and Gas Chromatography

Illicium verum Hook. f. is used as an herbal tea to treat colic pain in infants. Reports suggest that Star anise herbal tea may be adulterated with Illicium anisatum Linn. A short and rapid method using microscopy and gas chromatography (GC) was developed to detect I. anisatum Linn., an adulterant in the powdered mixture of I. verum. Anatomical differences in the epicarp cells of I. verum and I. anisatum fruits were clearly defined as examined under fluorescent microscopy and scanning electron microscopy. A GC method was developed for quick identification of possible I. anisatum adulteration with I. verum.