This study investigates the influence of some chemical additives such as methanol, ethanol, sodium oleat, chloroform and sodium hexametaphosphate (SHMP) on the dry fine grinding of calcite (X50= 33 µm) using a stirred media mill. The experiments were carried out by a batch operation, and the change in colour properties (Ry, whiteness and yellowness) of calcite powder. The results showed that th...

Grinding and polishing are widely used surface finish operations for a variety of precision and delicate component of ceramics, such as silicon wafers and gauges. However, the formation and evaluation of the subsurface damage induced have not been investigated, although subsurface damage is extremely important to the quality of the products. Grinding and polishing are usually carried out by a s...

The processing of woody biomass waste piles for use as fuel instead of burning them was 11 investigated. At each landing slash pile location, a 132 kW grapple excavator was used to transfer 12 the waste piles into a 522 kW horizontal grinder. Economies of scale could be expected when 13 grinding a larger pile, although the efficiency of the loading operation might be diminished. Here, 14 three ...

A comparison is made of the mechanochemical activation of three low- and one high-defect kaolinite using a combination of X-ray diffraction, thermal analysis, and DRIFT spectroscopy. The effect of mechanochemical alteration of the kaolinites is greater for the low-defect kaolinites. The effectiveness of the mechanochemical treatment is represented by the slope of the d(001) peakwidth-grinding t...

The aim of this study was to determine a suitable amount of grinding of a flexural test specimen for clinical evaluation of dental ceramics. Three dental ceramics (Crys-Cera, OCC and IPS Empress Cosmo) were selected. Five types of bar-shaped patterns were prepared for a three-point bending test, and four types of disk-shaped patterns for a biaxial flexural test. Ceramic specimens were fabricate...

-A vermiculite (Libby, Montana) sample obtained from the Zonolite company contained mostly coarse-grained separates with only 8.7 per cent clay. The 2-50 #m fraction was used for particle-size reduction studies by wet and dry grinding, and size-fractionated into < 2, 2-5, 5-20 and 20--50 #m sizes. About 18 per cent of the sample was attrited to clay after 64 hr of wet grinding, but as much as 5...

The cogrinding technique is one of most effective methods for improving the dissolution of poorly water-soluble drugs and it is superior to other approaches from an economical as well as an environmental standpoint, as the technique does not require any toxic organic solvents. Present work explores the role of d-glucosamine HCl (GL) as a potential excipient to improve dissolution of a low melti...

The purpose of this paper is to understand the combined effect of thermal and mechanical plastic deformation on residual stresses in ground components. The interactions between a grinding wheel and a workpiece, including both thermal and mechanical interaction, are simulated by triangular surface loads moving with the table speed of grinding. Cooling is modelled by a uniform convection over the...

In the current work we present approach to study the mechanism of the cutting of abrasive grains in the grinding wheel using finite element analysis (FEA). The simulation process is done by separating two abrasive grains from the grinding wheels and the microprocess of material removal in the case of surface grinding is simulated. Modelling was done on the workpiece steel S-7 and material grain...

The mechanochemical dechlorination of pentachlorophenol (PCP) was studied using CaO and SiO2 powder as additives. The effects of the milling time and additives on the dechlorination rate were investigated. The resulting product was characterized by X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), thermogravimetric analysis (TG) and ion chromatography (IC). It is found that g...