Thermal response of electrodeposited copper

Thermal response of electrodeposited copper has been characterized by monitoring changes in microstructure, tensile strength, elongation, and microhardness following 30 minute isothermal anneal at temperatures between 23 and 450°C. By judicious control of additives to the electrolyte, considerable enhancements of strength, hardness, and anneal resistance are obtained. When recrystallization is shifted to higher temperatures, annealing proceeds by recovery-like processes; prior to the onset of recrystallization, significant strength loss may occur by recovery. Recrystallization initiates near the substrate side of the deposit and progresses along an uneven front across the deposit thickness. The microhardness and tensile response monitors indicate several unusual anneal-related microstructural processes: (i) precipitation (of microvoids) hardening, (ii) dissolution and reprecipitation, (iii) stepped progress of recovery and recrystallization, and (iv) embrittlement (loss of elongation) at low anneal temperatures and prior to the onset of recrystallization.     

A framework for systems analysis for decision support systems

Comprehensive and elaborate systems analysis techniques have been developed in the past of routine and operational information systems. Developing support systems for organizational decision-making requires new tools and methodologies. We present a new framework for data collection and decision analysis which is useful for developing decision support systems. This task analysis methodology encompasses (1) event analysis, (2) participant analysis, and (3) decision content analysis. With a proper coding manual, it provides a framework for collecting relevant and detailed information required for decision support design and implementation. Further research is suggested for application and evaluation of the methodology in real-life DSS environments.     

Synthesis and characterization of CeO2 supported ZSM-5 zeolite for organic dye degradation

Journal of Materials Science: Materials in Electronics - ZSM-5:CeO2 nanocomposites were prepared by two-step hydrothermal method in combination with the wet impregnation method. The synthesized...     

Measurements of particle number and mass concentrations and size distributions in a tunnel environment

Particulate matter emissions were measured in two bores of the Caldecott Tunnel in Northern California during August and September 2004. One bore (Bore 1) is open to both heavy- and light-duty vehicles while heavy-duty vehicles are prohibited from entering the second bore (Bore 2). Particulate matter number and mass size distributions, chemical composition, and gaseous copollutants were recorded for four consecutive days near the entrance and exit of each bore. Size-resolved emission factors were determined for particle number, particle mass, elemental carbon, organic carbon (OC), sulfate, nitrate, and selected elements. The size distributions in both the bores showed a single large mode at roughly 15-20 nm in mobility diameter, with occasional smaller modes around 100 nm. The PM10 mass emission factor for heavy-duty vehicles was 14.5 times higher than that of light-duty vehicles. The particles derived from diesel are more abundant in elemental carbon, 70.9% of PM10 emissions, as compared to the light-duty vehicles. Conversely, a greater percentage of OC was found in light-duty emissions than heavy-duty emissions. In comparison to previous studies at the Caldecott Tunnel, less particle mass but more particle numbers are emitted by vehicles than was the case 7 years ago.     

Atomic vapor deposition approach to In2O3 thin films

In2O3 thin films were grown by atomic vapor deposition (AVD) on Si(100) and glass substrates from a tris-guanidinate complex of indium [In(N(i)Pr2guanid)3] under an oxygen atmosphere. The effects of the growth temperature on the structure, morphology and composition of In2O3 films were investigated. X-ray diffraction (XRD) measurements revealed that In2O3 films deposited in the temperature range 450-700 degreesC crystallised in the cubic phase. The film morphology, studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM), was strongly dependent on the substrate temperature. Stoichiometric In2O3 films were formed under optimised processing conditions as was confirmed by X-ray photoelectron and X-ray excited Auger electron spectroscopies (XPS, XE-AES), as well as by Rutherford backscattering spectrometry (RBS). Finally, optical properties were investigated by photoluminescence (PL) measurements, spectroscopic ellipsometry (SE) and optical absorption. In2O3 films grown on glass exhibited excellent transparency (approximately 90%) in the Visible (Vis) spectral region.     

The effect of inulin as a fat replacer on the quality of low‐fat ice cream

The influence of different levels of inulin as fat replacer on the quality of ice cream was investigated. Inulin was added at 2, 4 and 6% to replace milk fat and the experimental ice creams were compared to a control with 10% milk fat. The chemical composition, overrun, water activity, viscosity, melting rate, hardness and colour value were determined. Sensory properties of the ice cream samples were evaluated during storage. The overall acceptability of ice creams prepared with 2 and 4% substitution were similar to the control.     

Non-uraninite products of microbial U(VI) reduction

A promising remediation approach to mitigate subsurface uranium contamination is the stimulation of indigenous bacteria to reduce mobile U(VI) to sparingly soluble U(IV). The product of microbial uranium reduction is often reported as the mineral uraninite. Here, we show that the end products of uranium reduction by several environmentally relevant bacteria (Gram-positive and Gram-negative) and their spores include a variety of U(IV) species other than uraninite. U(IV) products were prepared in chemically variable media and characterized using transmission electron microscopy (TEM) and X-ray absorption spectroscopy (XAS) to elucidate the factors favoring/inhibiting uraninite formation and to constrain molecular structure/composition of the non-uraninite reduction products. Molecular complexes of U(IV) were found to be bound to biomass, most likely through P-containing ligands. Minor U(IV)-orthophosphates such as ningyoite [CaU(PO(4))(2)], U(2)O(PO(4))(2), and U(2)(PO(4))(P(3)O(10)) were observed in addition to uraninite. Although factors controlling the predominance of these species are complex, the presence of various solutes was found to generally inhibit uraninite formation. These results suggest a new paradigm for U(IV) in the subsurface, i.e., that non-uraninite U(IV) products may be found more commonly than anticipated. These findings are relevant for bioremediation strategies and underscore the need for characterizing the stability of non-uraninite U(IV) species in natural settings.     

Microbial technologies for heavy metal remediation: effect of process conditions and current practices

Clean Technologies and Environmental Policy - Heavy metal (HM) contamination is a persisting environmental problem in many countries. The major sources of soil contamination due to heavy metals...