92 resultados para Ferritin-Reference value


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The present study evaluates the feasibility of undelimbed Scots pine (Pinus sylvestris L.) for integrated production of pulp and energy in a kraft pulp mill from the technical, economic and environmental points of view, focusing on the potential of bundle harvesting. The feasibility of tree sections for pulp production was tested by conducting an industrial wood-handling experiment, laboratory cooking and bleaching trials, using conventional small-diameter Scots pine pulpwood as a reference. These trials showed that undelimbed Scots pine sections can be processed in favourable conditions as a blend with conventional small-diameter pulpwood without reducing the pulp quality. However, fibre losses at various phases of the process may increase when using undelimbed material. In the economic evaluation, both pulp production and wood procurement costs were considered, using the relative wood paying capability of a kraft pulp mill as a determinant. The calculations were made for three Scots pine first-thinning stands with the breast-height diameter of the removal (6 12 cm) as the main distinctive factor. The supply chains included in the comparison were based on cut-to-length harvesting, whole-tree harvesting and bundle harvesting (whole-tree bundling). With the current ratio of pulp and energy prices, the wood paying capability declines with an increase in the proportion of the energy fraction of the raw material. The supply system based on the cut-to-length method was the most efficient option, resulting in the highest residual value at stump in most cases. A decline in the pulp price and an increase in the energy price improved the competitiveness of the whole-tree systems. With short truck transportation distances and low pulp prices, however, the harvesting of loose whole trees can result in higher residual value at stump in small-diameter stands. While savings in transportation costs did not compensate for the high cutting and compaction costs by the second prototype of the bundle harvester, an increase in transportation distances improved its competitiveness. Since harvesting undelimbed assortments increases nutrient export from the site, which can affect soil productivity, the whole-tree alternatives included in the present study cannot be recommended on infertile peatlands and mineral soils. The harvesting of loose whole trees or bundled whole trees implies a reduction in protective logging residues and an increase in site traffic or payloads. These factors increase the risk of soil damage, especially on peat soils with poor bearing capacity. Within the wood procurement parameters which were examined, the CO2 emissions of the supply systems varied from 13 27 kg m3. Compaction of whole trees into bundles reduced emissions from transportation by 30 39%, but these reductions were insufficient to compensate for the increased emissions from cutting and compaction.

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In order to further develop the logic of service, value creation, value co-creation and value have to be formally and rigorously defined, so that the nature, content and locus of value and the roles of service providers and customers in value creation can be unambiguously assessed. In the present article, following the underpinning logic of value-in-use, it is demonstrated that in order to achieve this, value creation is best defined as the customer’s creation of value-in-use. The analysis shows that the firm’s and customer’s processes and activities can be divided into a provider sphere, closed for the customer, and a customer sphere, closed for the firm. Value creation occurs in the customer sphere, whereas firms in the provider sphere facilitate value creation by producing resources and processes which represent potential value or expected value-in use for their customers. By getting access to the closed customer sphere, firms can create a joint value sphere and engage in customers’ value creation as co-creators of value with them. This approach establishes a theoretically sound foundation for understanding value creation in service logic, and enables meaningful managerial implications, for example as to what is required for co-creation of value, and also further theoretical elaborations.