in this study, an efficient and facile technique for preparing graphene oxide in suspension and powder forms was presented based on a modification on hummers' method followed by an additional ultrasonic process. the method involved the provision of graphene oxide from graphite by reaction of potassium permanganate and sulfuric acid with stabilizing the medium complex. furthermore, this stu...

Graphenes are an emerging class of carbon nanomaterials whose adsorption properties toward organic compounds have not been well understood. In the present study, graphene nanosheets were prepared by reoxidation and abrupt heating of graphite oxide, which was prepared by sequential chemical oxidation of commercial nonporous graphite powder. Adsorption properties of three aromatic compounds (naph...

Graphite is commonly used in brake pads. The use of graphite powder has the main goal of solid state lubrication and friction coefficient stabilization. In this article results on resin bonded brake pads with focus on noise performance and heat dissipation are presented. Experimental tests are based on model friction materials with a known formulation and a reduced number of components for a be...

The present work aims at contributing to the study of the complex phenomenon of wear of pin on disc contact in dry sliding friction between two material couples (bronze/steel and unsaturated polyester virgin and charged with graphite powder/steel). The work consists of the determination of the coefficient of friction, the study of the influence of the tribological parameters on this coefficient...

low water-wettability and oxidation resistance of graphite have limited its application in carbon containing refractory castables. the aims of this study were improvement of water-wettability and the oxidation resistance of natural flaky graphite by applying an oxide coating on its surface. to develop the coating, magnesium aluminate spinel sol was formulated via a citrate-nitrate route and gra...

production of fe-c alloy powders by mechanical alloying was studied. fe and graphite elemental powdermixtures containing 0.8 and 1.5wt.% graphite were mechanically alloyed using a planetary ball mill. thestructural changes of powder particles during mechanical alloying were studied by x-ray diffractometery,scanning electron microscopy and microhardness measurements. for both compositions, mecha...

Cubic diamond was synthesized with two systems, (1) graphite with pure magnesium carbonate (magnesite) and (2) graphite with mixed potassium and magnesium carbonate at pressures and temperatures above 9.5 GPa, 1600 ±C and 9 GPa, 1650 ±C, respectively. At these conditions (1) the pure magnesite is solid, whereas (2) the mixed carbonate exists as a melt. In this pressure range, graphite seems to ...

The amount of polyynes produced by Nd:YAG laser (355, 532, and 1064 nm) ablation of fullerene and graphite pellet targets was the largest for 1064 nm ablation, contrary to the powder target in the previous report. This result is believed to come from the difference in the main polyyne-production area in liquids in the optical cell, depending on the pellet and powder targets.

In this study, mechanical alloying was done by a high-energy planetary ball milling technique. A mixture of NiO and MoO3 and graphite powders were used as initial materials. After milling of powder mixture with 40 wt.% additional graphite, a temperature of 400, 550 and 1000 °C for 1 h was considered for the heat treatment of powder mixture. Also, powder mixtures containing 60, 80 and 100 wt.% a...