Encapsulation in cement is the favoured method in the UK for disposal of intermediate and low level radioactive wastes. It is usual to use composite cement systems incorporating blast furnace slag (BFS) or pulverised fuel ash (PFA) as these offer several advantages over Portland cement, notably a lower heat of hydration. The use of these mineral additions utilises a waste product which would itself need a disposal route and, because of the decreased amount of Portland cement used, provides a reduction in cost and energy consumption. Cementitious systems have many attributes which make them suitable for encapsulation and immobilisation, including: • Inexpensive and readily available; • Assist immobilisation of radionuclides by: a) acting as a diffusion barrier, b) providing sorption and reaction sites, c) maintaining a high pH which in turn decreases radionuclide solubility; • Provide radiation shielding which is not degraded by the radiation; • Controllable permeation and diffusion characteristics over a wide range via selection of constituents and components. Where physical adsorption is a significant factor for immobilisation, the calcium silicate hydrate gel (C-S-H) formed on hydration of a Portland cement is advantageous as it has a high surface area and large micropore volume. Composite cements based on blast furnace slag will produce a higher proportion of C-S-H than ordinary Portland cement increasing the sorption capacity, and reducing the capillary porosity so that the diffusion resistance is increased. Intermediate level waste covers a wide range of materials, for example, metals and ion exchangers, each with differing chemical properties. It is, therefore, necessary to access the ability of the cementitious system to immobilise different wastes and to characterise the products formed. It is also necessary that alternative encapsulant materials be considered for immobilising wastes not suited to the composite cements already being used. The techniques employed to do this include x-ray diffraction (XRD), to identify standard and non-standard hydration products, isothermal conduction calorimetry (ICC) and scanning electron microscopy (SEM).
This article presents a review and analysis of empirically based research on strategic management in nonprofit organizations appearing in peer-reviewed journals between 1998 and 2015, and compares these findings with an earlier, similar study to determine how nonprofit use of strategic management has evolved over time. Findings suggest that determinants of strategic management have evolved beyond funder requirements to include environmental pressures to increase organizational efficiency and effectiveness, professionalize staff capacities, and respond to changing customer requirements. Nonprofits continue to use strategic management in response, and have recently adopted a wide range of for-profit strategies and practices in both strategy content and strategy performance areas. Strategic management offers both risks and rewards for nonprofits, but requires significant time, resources, and human capital that not all nonprofits readily possess.RÉSUMÉCet article présente l’évaluation et l’analyse de recherches empirique—parues entre 1998 et 2015 dans des revues évaluées par les pairs—sur la gestion stratégique d’organismes à but non lucratif. Il compare ces données avec uneétude antérieure similaire afin de déterminer comment la gestion stratégique par les organismes à but non lucratif a évolué. Les résultats suggèrent que les déterminants de la gestion stratégique ont progressé au-delà des besoins des subventionneurs, tenant compte aujourd’hui des pressions environnementales pour accroître l’efficience et l’efficacité organisationnelles, professionnaliser le personnel et répondre aux besoins changeants de la clientèle. Dans ces circonstances, les organismes à but non lucratif continuent de recourir à la gestion stratégique et ont récemment adopté un vaste éventail de stratégies et pratiques à but lucratif dans les domaines du contenu et de la performance stratégiques. La gestion stratégique, tout en posant certains risques, offre incontestablement des récompenses aux organismes à but non lucratif, mais elle requiert un temps, des ressources et une main d’oeuvre que les organismes à but non lucratif ne possèdent pas forcément.
Talc has been used for over a century in a variety of cosmetic products. While pure cosmetic talc (free of asbestos) is not considered a risk factor for mesothelioma, it has been recently suggested that inhalation of cosmetic talc containing trace levels of asbestos is a risk factor for mesothelioma. Bulk analyses of cosmetic talcum products were performed in the 1960s and 1970s, however, the analytical methods used at that time were incapable of determining whether asbestos minerals were present in the asbestiform versus non-asbestiform habit. The distinction between these two mineral habits is critical, as non-asbestiform amphibole minerals do not present an asbestos-related cancer risk via inhalation. As such, we evaluated six historical talcum powders using modern-era analytical methods to determine if asbestos is present, and if so, to identify the mineral habit (asbestiform versus non-asbestiform) of the asbestos. Based on their labels, the products were produced by four manufacturers and sold between 1940 and 1977. The products were analyzed in duplicate by two laboratories using standard protocols. Laboratory A analyzed samples using X-ray diffraction (XRD) and polarized light microscopy (PLM), and Laboratory B analyzed samples using PLM and transmission electron microscopy (TEM) with energy dispersive X-ray analysis (EDX) and selected area electron diffraction (SAED). No asbestiform minerals were found in any of the products. Nonetheless, even if some historical cosmetic talcum products contained trace amounts (≤0.1%) of asbestiform minerals, any resulting asbestos exposure would be expected to be exceedingly low, and comparable to exposures from breathing ambient air.
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