In this research, self-assembled copper sulfide nanospheres were synthesized by the solvothermal method and the effects of reaction parameters, including reaction time and reaction temperature on the morphology and phase evolution of copper sulfide nanostructures were investigated. For the identification of copper sulfide nanostructures, X-ray diffraction (XRD), infrared spectroscopy (FT-IR), f...

The temperature dependence of electrical resistivity was measured for three materials: a conductor (copper), a semiconductor (a carbon resistor), and a doped semiconductor (a pn junction). As expected, the resistance of the copper sample decreased with temperature and the resistance of the carbon resistor increased with temperature. The temperature coefficient of resistance of Cu was calculated...

The aim of this investigation was to determine the efficacy of chalcopyrite bioleaching using pure cultures of Acidithiobacillus ferrooxidans or Acidithiobacillus thiooxidans and a mixed culture composed of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. The experiments were carried out in shake flasks with [Fe] 4 gL 1 and S 1 gL 1 at pH 1.80, 130 rpm and 30 C. Inocula of both...

* Work supported by U. S. Department of Energy, contract number DE-AC03-76F00515 Using laboratory scale and full size PEP-II vacuum chambers, chemical cleaning, glow discharge and thermal process effects were evaluated using surface analysis by xray photoelectron spectroscopy (XPS). These processes were optimized to reduce surface carbon and thereby minimize photodesorption gas loads. The relat...

Tapping mode atomic force microscopy (TM-AFM) was used for the investigation of the early stages of atmospheric corrosion of pure copper and pure iron. The information obtained by this method is the change of the topography of the sample surfaces with emphasis on the shape and lateral distribution of the corrosion products grown within the first 1300 min of weathering. Investigations were carri...

The surface roughness of the substrate itself could play an important role for the bonding at the interface. In this paper, a correlation of the surface roughness of a rigid alumina substrate and its 2D model of estimated surface area has been studied using Atomic Force Microscopy (AFM). With rougher surface, the adhesive strength between a deposited copper film and the alumina substrate is hig...

The ability to fabricate geometrically complex copper shapes via Additive Manufacturing (AM) could have a significant impact on the design and performance of thermal management systems and structural electronics. In this research a Binder Jetting AM process (ExOne R2) was used to fabricate green parts made of high purity copper powder. Once printed, the green part was sintered under a reducing ...

Mixed copper-cerium oxides were prepared by two methods leading to different wpper species in the as-prepared material. At the catalyst operating temperature (300400°C) and above, the same copper species was present irrespective of the prepration technique. A solid solution having the same fluorite structure as that of pure CeQ was formed and remained stable after calcination to 100O0C. At temp...

A chemical reduction method for preparing monodispersed pure-phase copper colloids in water and ethylene glycol has been reported. Owing to the reduction property of ethylene glycol, the reaction rate in ethylene glycol is higher than that in water. In addition, the amount of reducing agent can be reduced largely. Ascorbic acid plays roles as reducing agent and antioxidant of colloidal copper, ...

We report the fabrication and characterization of a photonic crystal fiber (PCF) having a sol-gel core doped with ionic copper. Optical measurements demonstrate that the ionic copper is preserved in the silica glass all along the preparation steps up to fiber drawing. The photoluminescence results clearly show that such an ionic copper-doped fiber constitutes a potential candidate for UV-C (200...