In this work, a study of the influence of the starting materials and the processing time used to develop W/Cu alloys is carried out. Regarding powder metallurgy as a promising fabrication route, the difficulties in producing W/Cu alloys motivated us to investigate the influential factors on the final properties of the most industrially demanding alloys: 85-W/15-Cu, 80-W/20-Cu, and 75-W/25-Cu al...

LetR be a finitely generated commutative algebra over an algebraically closed field k and let A = R[t;σ, δ] be the Ore extension with respect to an automorphism σ and a σ-derivation δ. We view A as the coordinate ring of an affine non-commutative space X. The inclusion R → A gives an affine map ξ : X → SpecR, and X is a non-commutative analogue of A 1 ×SpecR. We define the fiber Xp of ξ over a ...

The present research concerns an electrodeposited cobalt-tungsten alloy coating on graphite fibers. Annealed and unannealed coated fibers were analyzed by scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS), x-ray diffraction (XRD), and transmission electron microscopy (TEM). The mole fraction of tungsten in the as-deposited cobalt-tungsten coating was found to be (7.10 ...

OBJECTIVES The aim of this study was to determine the apical surface characteristics and presence of dental cracks in single-rooted premolars, resected 3.0 mm from the root apex, using the Er: YAG laser, tungsten carbide bur, and diamond-coated tip, by scanning electron microscopy (SEM). EXPERIMENTAL DESIGN Thirty single-rooted premolar teeth were collected. The instrumented and obturated tee...

Spatial patterns of tungsten and cobalt are described for surface dust of Fallon, Nevada, where a cluster of childhood leukemia has been ongoing since 1997. In earlier research, airborne tungsten and cobalt was shown to be elevated in total suspended particulates in Fallon. To fine-tune the spatial patterns of tungsten and cobalt deposition in Fallon, surface dust was collected in a grid patter...

Core samples recovered from exploration boreholes and granite/greisen outcrops at the Panasqueira world-class tungsten deposit in central Portugal were subjected to chemical analyses petrographic studies. We present a geochemical dataset trace element compositions of quartz micas large part unexposed granitic pluton. Our data suggest that hidden granite body is more complicated than previously ...

Shortwave infrared (SWIR) technology is characterized by high efficiency and convenience widely used in the mineral exploration of porphyry, epithermal, skarn types. However, studies on SWIR spectral features porphyry tungsten deposits are still lacking. The Dahutang deposit has reached an ultra large scale, type. Based white mica its petrographic, geochemical, Raman features, this paper discus...

The subresultants play a fundamental role in elimination theory and computer algebra. Recently they have been extended to Ore polynomials. They are de ̄ned by an expression in the coe±cients of Ore polynomials. In this paper, we provide another expression for them. This expression is written in terms of the \solutions" of Ore polynomials (in \generic" case). It is a generalization of our previou...

Silica sand is widely used in the transformation industry. For instance, it is used in the making of glass, silicates, paints, glass-ceramics and ceramics. Traditionally, glass and ceramic materials have been manufactured using high-purity silica and minerals taken from ore on the surface of the earth. However, during recent decades, the manufacture of household and industrial products has incr...

A traceability system simplifies investigation of causes of product failures and is therefore vital for many industries. Traceability systems are extensively used in manufacturing industries, but creating traceability in continuous processes implies great challenges. The aim of this paper is to illustrate how traceability can be achieved in the distribution chain for iron ore pellets. Radio fre...