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This contribution reports, for the first time, on an entirely green bio-engineering approach for the biosynthesis of single phase crystalline 1-D nano-scaled calcite CaCO3. This was validated using H2O as the universal solvent and natural extract of Hyphaene thebaica fruit as an effective chelating agent. In this room temperature green process, CaCl2 and CO2 are used as the unique source of Ca and CO3 respectively in view of forming nano-scaled CaCO3 with a significant shape anisotropy and an elevated surface to volume ratio. In terms of novelty, and relatively to the reported scientific and patented literature in relation to the fabrication of CaCO3 by green nano-chemistry, the current cost effective room temperature green process can be singled out as per the following specificities: only water as universal solvent is used, No additional base or acid chemicals for pH control, No additional catalyst, No critical or supercritical CO2 usage conditions, Only natural extract of thebaica as a green effective chelating agent through its phytochemicals and proper enzematic compounds, room Temperature processing, atmospheric pressure processing, Nanoscaled size particles, and Nanoparticles with a significant shape anisotropy (1-D like nanoparticles). Beyond and in addition to the validation of the 1-D synthesis aspect, the bio-engineered CaCO3 exhibited a wide-ranging functionalities in terms of highly reflecting pigment, an effective nanofertilizer as well as a potential binder in cement industry. [ABSTRACT FROM AUTHOR]

The measurement of the degree of redeposition of sputtered species during the etching of platinum (Pt), barium-strontium-titanate (BST), strontium-bismuth-tantalate (SBT), and photoresist (PR) in a high-density argon plasma is reported. The result data shows that depending on the plasma etching conditions, redepostion effect could induce misinterpretation of the etch rate data.

Numerous techniques are used to explain the microstructural, surface morphology and the optical properties of barium strontium titanate ([Ba.sub.0.5][Sr.sub.0.5Ti[O.sub.3] or BST) films deposited by the pulsed laser deposition technique. The films explained are found to be extremely helpful, as they can be widely used for several low loss waveguide, as well as different advanced optical integrated systems.

Forest areas of the Mediterranean regions of Portugal, Morocco, and Tunisia are suffering major land use changes, with the replacement of traditional evergreen Quercus species (i.e. Quercus suber and Quercus ilex) by fast-growing Eucalyptus species. Since Eucalyptus species are amongst those with a higher impact on soil water repellency, this study examined the effect of the replacement on soil properties, water repellency, and on soil hydrological processes and erosion rates. Measurements were performed in areas that correspond to the climatic distribution of evergreen Quercus suber: at Macao and Portel in Portugal; Ben Slimane in Morocco; and Cap Bon, Sousse, and Ain Snoussi in Tunisia. Soil superficial characteristics, including vegetation and litter cover, organic matter content, soil compaction and shear strength, and water repellency were measured for evergreen oak and Eucalyptus stands and related to soil erosion rates and soil hydrological processes. The data are based on the spatial distribution of properties assessed through the use of intensive spatial sampling and on rainfall simulations to address soil hydrological and erosional processes. The results show very different wetting patterns for some of the Eucalyptus stands during dry and moist periods, as a result of strong hydrophobic characteristics following dry spells. Nevertheless, the Eucalyptus stands in semi-arid climate show no sign of water repellency, which contradicts the theory that water repellency is purely a result of dry conditions. The experiments show no significant increases on overland flow amounts and erosion rates as direct result of soil water repellence (hydrophobicity) characteristics. Additional keywords: Quercus suber, Eucalyptus spp., water repellency, overland flow, erosion, Mediterranean., Introduction Changes of similar sign are occurring on lands unsuitable for agriculture on both sides of the Western Mediterranean Sea (Hamza 1994; Ferreira et al. 1997; Carvalho et al. 1999; [...]

Inlet fogging of gas turbine engines has attained considerable popularity due to the ease of installation and the relatively low first cost compared to other inlet cooling methods. With increasing demand for power and with shortage envisioned especially during the peak load times during the summers, there is a need to boost gas turbine power. There is a sizable evaporative cooling potential throughout the world when the climatic data is evaluated based on an analysis of coincident wet bulb and dry bulk information. These data are not readily available to plant users. In this paper, a detailed climatic analysis is made of 122 locations in the U.S. to provide the hours of cooling that can be obtained by direct evaporative cooling. These data will allow gas turbine operators to easily make an assessment of the economics of evaporative cooling. The paper also covers an introduction to direct evaporative cooling and the methodology and data analysis used to derive the cooling potential in different regions of the U.S. Simulation runs have been made for gas turbine simple cycles using a reference plant based on a GE Frame 7111EA gas turbine at the 122 locations studied in the U.S. to provide a feel for the sensitivity of operation with inlet fogging. [DOI: 10.1115/1.1519266]

Laser ablation experiments were undertaken on aluminum and silicon using ultrashort laser pulses.

The pure physical etching characteristics of platinum thin films is examined by using a high-density surface-wave magnetized argon plasma operated in the very low pressure regime together with a rf biased system. The findings indicate that using high-density plasma in the very low-pressure regime yields high etch rates with a good selectivity over resist.