Abundant graphite particles occur in amphibolite-grade quartzite of the Archean-Paleoproterozoic Wutai Metamorphic Complex in the Wutaishan area of North China. Petrographic thin section observations suggest that the graphite particles occur within and between quartzite clasts and are heterogeneous in origin. Using HF maceration techniques, the Wutai graphite particles were extracted for furthe...

Hollow polyhedral graphite particles with 200~400 nm in diameter have been synthesized by heating oxalic acid, ferrocene and metallic magnesium at 580 °C, typically forming diamond-like octahedral structure. Combined with SEM, TEM, SAED patterns, and Raman spectroscopy, it was shown that the surface of graphite polyhedrons is composed of approximately 30-40 graphene shells; the fouror sixfold s...

This article reports the microstructural characteristics of various petroleum and pitch based nuclear graphites (IG-110, NBG-18, and PCEA) that are of interest to the next generation nuclear plant program. Bright-field transmission electron microscopy imaging was used to identify and understand the different features constituting the microstructure of nuclear graphite such as the filler particl...

In this work we reported a novel graphite doped conductive magnetorheological plastomer (GMRP) with magnetic field dependent electro-conductivity. The conductivity of the GMRPs increased by increasing the content of the graphite particles, while it decreased with the graphite size. When the graphite content reached 15 wt%, the conductivity of GMRPs is approximately 10 000 times higher than the ...

In this study, Al/Gr composites with 5,10,15,20 weight percent of graphite were produced by in-situ powder metallurgy method. The produced powder mixtures were consolidated and sintered at optimum conditions. The resultant composites were solution treated at 495?C and aged at 170?C. The influence of graphite content on the bending strength of composites was studied. The distribution of graphite...

In this work a pH-sensitive poly(acrylamide-co-itaconic acid)/ graphite composite hydrogel is prepared by free radical initiated polymerization of monomers acrylamide(Am) and itaconic acid(IA) in the presence of settled graphite(Gt) particles using N,N’-methylene bisacrylamide(MB) as cross linker in aqueous medium. The SEM analysis revealed almost uniform distribution of grafite particles withi...

Submitted for the MAR16 Meeting of The American Physical Society Fe-catalyzed etching of graphene layers GUANGJUN CHENG, IRENE CALIZO, ANGELA HIGHT WALKER, NIST, PML, NIST TEAM — We investigate the Fe-catalyzed etching of graphene layers in forming gas. Fe thin films are deposited by sputtering onto mechanically exfoliated graphene, few-layer graphene (FLG), and graphite flakes on a Si/SiO2 sub...

friction stir processing was applied for fabricating an aluminum alloy based hybrid nano composite reinforced with nano sized al2o3 and micro sized graphite particles. a mixture of al2o3 and graphite particles was packed into a groove with 1 mm width and 4.5 mm depth, which had been cut in 5083 aluminum plate of 10 mm thick. packed groove was subjected to friction stir processing in order to im...

A new model is proposed for the encapsulation of catalyst metal particles by graphite layers that are obtained, for example, in low-temperature chemical vapor deposition production of carbon nanotubes (CNTs). In this model graphite layers are primarily formed from the dissolved carbon atoms in the metal-carbide particle when the particle cools. This mechanism is in good agreement with molecular...

Of the “presolar particles” extracted from carbonaceous meteorite dissolution residues, i.e., of those particles that show isotopic evidence of formation in the neighborhood of other stars prior to the origin of our solar system, a subset of the onion-like graphite spheres has an interesting concentric graphene core–graphite rim structure. We show here that single graphene sheet defects in the ...