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Summary: The relationship between environmental life cycle costing (ELCC) and sustainability was explored using two detailed wastewater case studies. The case studies were selected to increase the tension between existing market values and values for sustainability; the first case study considered incremental change to an existing plant and the second considered a paradigm shift in wastewater treatment. Pollution control provided the greatest cost savings for the first case study and provided a “win‐win” result—meeting existing standards and saving money. However, benefits for pollution control beyond current standards were not captured, which emphasized the role of standards to internalize as well as limit the values considered in ELCC. In the second case study, the value of water had the potential to change the focus of wastewater design from pollution abatement to resource recovery. However, social acceptance of recovered water and market access for resources created large risk for investment. The ELCC was also sensitive to the discount rate which limited longer‐term considerations. Other sustainability values such as scarcity and ecological thresholds were not captured. The ELCC code of practice suggests including such costs if likely in the foreseeable future; defining these values may also clarify the role of ELCC to evaluate sustainability over the life cycle. [ABSTRACT FROM AUTHOR]

Electron-beam-induced carbon film deposition has long been recognized as a side effect of scanning electron microscopy. To characterize the nature of this type of contamination, silicon wafers were subjected to prolonged exposure to 15 kV electron beam energy with a probe current of ~300 pA. Using Raman spectroscopy, the deposited coating was identified as an amorphous carbon film with an estimated crystallite size of 125 Å. Using atomic force microscopy, the cross-sectional profile of the coating was found to be raised and textured, indicative of the beam raster pattern. A map of the Raman intensity across the coating showed increased intensity along the edges and at the corner of the film. The intensity profile was in excess of that which could be explained by thickness alone. The enhancement was found to correspond with a modeled local field enhancement induced by the coating boundary and showed that the deposited carbon coating generated a localized disturbance in the opto-electrical properties of the substrate, which is compared and contrasted with Raman edge enhancement that is produced by surface structure in silicon. [ABSTRACT FROM AUTHOR]

Dendrimers are three dimensional nanosized synthetic molecules that have internal cavities and numerous surface groups. In recent times they have received increased attention in sensing applications. For dendrimers to be used as sensors, they most commonly require functionalization at their surface. This is because the surface is generally the first point of contact between the dendrimer and the outside world, hence surface functionalization serves to selectively home in on the target analyte. Further, sensor signals may be transmitted through surface functionalities e.g. fluorochromic molecules. It is therefore important to document surface functionalization approaches. Dendrimers with amine surface groups have the advantage of being able to be conjugated to other molecules via an amide linkage, which is one of the most fundamental and widespread chemical bonds in nature. In this paper we demonstrate the properties of dendrimers that make them so applicable to sensing. We review several methods for functionalizing dendrimers via an amide linkage, as well as present a review of surface functionalized polyamidoamine, polyamine, and polypeptide dendrimers that have been employed for biological, chemical and molecular sensing. [ABSTRACT FROM AUTHOR]

The time-dependent wetting of sulfathiazole compacts with sessile water drops was evaluated using video microscopy. The influence of sulfathiazole crystalline form, particle size, pre-saturation with water, humidity and compaction pressure on the droplet spreading kinetics and contact angles are reported. The rate and extent of droplet spreading decreased for compact surfaces of high microscopic roughness; this was determined by atomic force microscopy (AFM). Pre-saturation of powder compacts with water (pre-saturated with sulfathiazole) enhanced droplet spreading and enabled pseudo-equilibrium contact angles to be determined for up to 10 min. Sessile-drop contact angles on both sulfathiazole powder compacts and single crystals are compared with particle contact angles determined by liquid penetration. This study has led to an improved understanding of the influence of physical heterogeneities and the face-specific surface chemistry of individual crystals on the wetting characteristics of pharmaceutical compacts. [Copyright &y& Elsevier]