982 resultados para steel will residue


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Half of the world's annual production of steel is used in constructing buildings and infrastructure. Producing this steel causes significant amounts of carbon dioxide to be released into the atmosphere. Climate change experts recommend this amount be halved by 2050; however steel demand is predicted to have doubled by this date. As process efficiency improvements will not reach the required 75% reduction in emissions per unit steel output, new methods must be examined to deliver service using less steel production. To apply such methods successfully to construction, it must first be known where steel is used currently within the industry. This information is not available so a methodology is proposed to estimate it from known data. Results are presented for steel flows by product for ten construction sectors for both the UK and the world in 2006. An estimate for steel use within a 'typical' building is also published for the first time. Industrial buildings and utility infrastructure are identified as the largest end-uses of steel, while superstructure is confirmed as the main use of steel in a building. The results highlight discrepancies in previous steel estimates and life-cycle assessments, and will inform future research on lowering demand for steel, hence reducing carbon emissions. © 2012 Elsevier B.V. All rights reserved.

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Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age.

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Identifying strategies for reducing greenhouse gas emissions from steel production requires a comprehensive model of the sector but previous work has either failed to consider the whole supply chain or considered only a subset of possible abatement options. In this work, a global mass flow analysis is combined with process emissions intensities to allow forecasts of future steel sector emissions under all abatement options. Scenario analysis shows that global capacity for primary steel production is already near to a peak and that if sectoral emissions are to be reduced by 50% by 2050, the last required blast furnace will be built by 2020. Emissions reduction targets cannot be met by energy and emissions efficiency alone, but deploying material efficiency provides sufficient extra abatement potential.

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In the face of increasing demand and limited emission reduction opportunities, the steel industry will have to look beyond its process emissions to bear its share of emission reduction targets. One option is to improve material efficiency - reducing the amount of metal required to meet services. In this context, the purpose of this paper is to explore why opportunities to improve material efficiency through upstream measures such as yield improvement and lightweighting might remain underexploited by industry. Established input-output techniques are applied to the GTAP 7 multi-regional input-output model to quantify the incentives for companies in key steel-using sectors (such as property developers and automotive companies) to seek opportunities to improve material efficiency in their upstream supply chains under different short-run carbon price scenarios. Because of the underlying assumptions, the incentives are interpreted as overestimates. The principal result of the paper is that these generous estimates of the incentives for material efficiency caused by a carbon price are offset by the disincentives to material efficiency caused by labour taxes. Reliance on a carbon price alone to deliver material efficiency would therefore be misguided and additional policy interventions to support material efficiency should be considered. © 2013 Elsevier B.V.

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Multi-impact of projectiles on thin 304 stainless steel plates is investigated to assess the degradation of ballistic performance, and to characterise the inherent mechanisms. Assessment of ballistic degradation is by means of a double-impact of rigid spheres at the same site on a circular clamped plate. The limiting velocity of the second impact, will be altered by the velocity of the antecedent impact. Finite element analyses were used to elucidate experimental results and understand the underlying mechanisms that give rise to the performance degradation. The effect of strength and ductility on the single and multi-impact performance was also considered. The model captured the experimental results with excellent agreement. Moreover, the material parameters used within the model were exclusively obtained from published works with no fitting or calibration required. An attempt is made to quantify the elevation of the ballistic limit of thin plates by the dynamic mechanism of travelling hinges. Key conclusions: The multi-hit performance scales linearly with the single-hit performance; and strength is a significantly greater effector of increased ballistic limit than ductility, even at the expense of toughness. © 2014 Elsevier Ltd.

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The authors have recently described a cold-formed steel portal framing system in which simple bolted moment-connections, formed through brackets, were used for the eaves and apex joints. Such connections, however, cannot be considered as rigid because of localised in-plane elongation of the bolt-holes caused by bearing against the bolt-shanks. To therefore predict the initial stiffness of such connections, it is necessary to know the initial bolt-hole elongation stiffness k(b). In this paper, a finite element-solid idealisation of a bolted lap joint in shear will be described that can be used to determine k(b); the results obtained are validated against experimental data. A beam idealisation of a cold-formed steel bolted moment-connection is then described, in which spring elements are used to idealise the rotational flexibility of the bolt-groups resulting from bolt-hole elongation: Using the value of k(b) in the beam idealisation, the deflections predicted are shown to be similar to those measured experimentally in laboratory tests conducted on the apex joint of a cold-formed steel portal frame. (C) 2003 Elsevier Ltd. All rights reserved.

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Details are given of a cold-formed steel portal framing system that uses simple bolted moment-connections for both the eaves and apex joints. However, such joints function as semi-rigid and, as a result, the design of the proposed system will be dominated by serviceability requirements. While serviceability is a mandatory design requirement, actual deflection limits for portal frames are not prescribed in many of the national standards. In this paper, a review of the design constraints that have an effect on deflection limits is discussed, and rational values appropriate for use with cold-formed steel portal frames are recommended. Adopting these deflection limits, it is shown through a design example how a cold-formed steel portal frame having semi-rigid eaves and apex joints can be a feasible alternative to rigid-jointed frames in appropriate circumstances.

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This paper investigates the pull-out behaviour (particularly the bearing resistance) of a steel grid reinforcement embedded in silty sand using laboratory tests and numerical analyses. It is demonstrated that the various common analytical equations for calculating the bearing component of pull-out resistance give a wide range of calculated values, up to about 200% disparity. The disparity will increase further if the issue of whether to use the peak or critical state friction angle is brought in. Furthermore, these equations suggest that the bearing resistance factor, N, is only a function of soil friction angle which is not consistent with some design guidelines. In this investigation, a series of large scale laboratory pull-out tests under different test pressures were conducted. The test results unambiguously confirmed that the N factor is a function of test pressure. A modified equation for calculating N is also proposed. To have more in-depth understanding of the pull-out behaviour, the tests were modelled numerically. The input parameters for the numerical analysis were obtained from laboratory triaxial tests. The analysis results were compared with the experimental results. Good agreement between experimental and numerical results was achieved if the strain-softening behaviour from peak strength to critical state condition was captured by the soil model used. © 2013 Elsevier Ltd.

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Copper is accumulated in recycled steels and is difficult to be removed during steelmaking processes when steel scrap is used as steel sources. Meanwhile, copper characteristic properties are of importance both to human beings and to animals and plants. In this paper, integrated copper coating was observed on the surface of copper-containing steels when the steels were heated at around 1150°C. However, the copper was separately scattered after heating at 1000°C. The forming mechanisms of copper coating will be discussed in detail. By choosing proper descaling reagent, self-generated oxidation-induced copper coating appeared on the steel surface. The method proposed in this work is environmentally friendly for nontoxic chemicals being used. In addition, this provides a new concept for producing protective composite by oxidizing from the substrate directly and there is no binding problem.

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Last Will and Testament of John Picard of the township of Niagara. He leaves his land which consists of part of Lot 113 in the township of Niagara to Annie Mariah Steel. The executors are John Stevens and Gilbert Anderson. The document was registered July 3, 1882 – instrument no. 1743, May 9, 1882.

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Letter to S.D. Woodruff from A. Jeffrey importer of Hardware, Iron, Steel, and Window Glass of St. Catharines, Ont. A. Jeffrey says that he will be able to supply Mr. Woodruff with glass and iron pipe, June 7, 1875.

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In the present work, Indigenous polymer coated Tin Free Steel cans were analyzed fortheir suitability for thermal processing and storage of fish and fish products following standard methods. The raw materials used for the development of ready to eat thermally processed fish products were found to be of fresh condition. The values for various biochemical and microbiological parameters of the raw materials were well within the limits. Based on the analysis of commercial sterility, instrumental colour, texture, WB-shear force and sensory parameters, squid masala processed to F0 value of 8 min with a total process time of 38.5 min and cook value of 92 min was chosen as the optimum for squid masala in tin free steel cans while shrimp curry processed to F0 7 min with total process time of 44.0 min and cook value of 91.1 min was found to be ideal and was selected for storage study. Squid masala and shrimp curry thermally processed in indigenous polymer coated TFS cans were found to be acceptable even after one year of storage at room temperaturebased on the analysis of various sensory and biochemical parameters. Analysis of the Commission Internationale d’ Eclirage L*, a* and b* color values showed that the duration of exposure to heat treatment influenced the color parameters: the lightness (L*) and yellowness (b*)decreased, and the redness (a*) significantly increased with the increase in processing time or reduction in processing temperature.Instrumental analysis of texture showed that hardness-1 & 2 decreased with reduction in retort temperature while cohesiveness value did not show any appreciable change with decrease in temperature of processing. Other texture profile parameters like gumminess, springiness and chewiness decreased significantly with increase of processing time. W-B shear force values of mackerel meat processed at 130 °C were significantly higher than those processed at 121.1 and 115 °C. HTST processing of mackerel in brine helped in reducing the process time and improving the quality.The study also indicated that indigenous polymer coated TFS cans with easy openends can be a viable alternative to the conventional tin and aluminium cans. The industry can utilize these cans for processing ready to eat fish and shell fish products for both domestic and export markets. This will help in reviving the canning industry in India.

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Computational Biology is the research are that contributes to the analysis of biological data through the development of algorithms which will address significant research problems.The data from molecular biology includes DNA,RNA ,Protein and Gene expression data.Gene Expression Data provides the expression level of genes under different conditions.Gene expression is the process of transcribing the DNA sequence of a gene into mRNA sequences which in turn are later translated into proteins.The number of copies of mRNA produced is called the expression level of a gene.Gene expression data is organized in the form of a matrix. Rows in the matrix represent genes and columns in the matrix represent experimental conditions.Experimental conditions can be different tissue types or time points.Entries in the gene expression matrix are real values.Through the analysis of gene expression data it is possible to determine the behavioral patterns of genes such as similarity of their behavior,nature of their interaction,their respective contribution to the same pathways and so on. Similar expression patterns are exhibited by the genes participating in the same biological process.These patterns have immense relevance and application in bioinformatics and clinical research.Theses patterns are used in the medical domain for aid in more accurate diagnosis,prognosis,treatment planning.drug discovery and protein network analysis.To identify various patterns from gene expression data,data mining techniques are essential.Clustering is an important data mining technique for the analysis of gene expression data.To overcome the problems associated with clustering,biclustering is introduced.Biclustering refers to simultaneous clustering of both rows and columns of a data matrix. Clustering is a global whereas biclustering is a local model.Discovering local expression patterns is essential for identfying many genetic pathways that are not apparent otherwise.It is therefore necessary to move beyond the clustering paradigm towards developing approaches which are capable of discovering local patterns in gene expression data.A biclusters is a submatrix of the gene expression data matrix.The rows and columns in the submatrix need not be contiguous as in the gene expression data matrix.Biclusters are not disjoint.Computation of biclusters is costly because one will have to consider all the combinations of columans and rows in order to find out all the biclusters.The search space for the biclustering problem is 2 m+n where m and n are the number of genes and conditions respectively.Usually m+n is more than 3000.The biclustering problem is NP-hard.Biclustering is a powerful analytical tool for the biologist.The research reported in this thesis addresses the problem of biclustering.Ten algorithms are developed for the identification of coherent biclusters from gene expression data.All these algorithms are making use of a measure called mean squared residue to search for biclusters.The objective here is to identify the biclusters of maximum size with the mean squared residue lower than a given threshold. All these algorithms begin the search from tightly coregulated submatrices called the seeds.These seeds are generated by K-Means clustering algorithm.The algorithms developed can be classified as constraint based,greedy and metaheuristic.Constarint based algorithms uses one or more of the various constaints namely the MSR threshold and the MSR difference threshold.The greedy approach makes a locally optimal choice at each stage with the objective of finding the global optimum.In metaheuristic approaches particle Swarm Optimization(PSO) and variants of Greedy Randomized Adaptive Search Procedure(GRASP) are used for the identification of biclusters.These algorithms are implemented on the Yeast and Lymphoma datasets.Biologically relevant and statistically significant biclusters are identified by all these algorithms which are validated by Gene Ontology database.All these algorithms are compared with some other biclustering algorithms.Algorithms developed in this work overcome some of the problems associated with the already existing algorithms.With the help of some of the algorithms which are developed in this work biclusters with very high row variance,which is higher than the row variance of any other algorithm using mean squared residue, are identified from both Yeast and Lymphoma data sets.Such biclusters which make significant change in the expression level are highly relevant biologically.

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A range of archaeological samples have been examined using FT-IR spectroscopy. These include suspected coprolite samples from the Neolithic site of Catalhoyuk in Turkey, pottery samples from the Roman site of Silchester, UK and the Bronze Age site of Gatas, Spain and unidentified black residues on pottery sherds from the Roman sites of Springhead and Cambourne, UK. For coprolite samples the aim of FT-IR analysis is identification. Identification of coprolites in the field is based on their distinct orange colour; however, such visual identifications can often be misleading due to their similarity with deposits such as ochre and clay. For pottery the aim is to screen those samples that might contain high levels of organic residues which would be suitable for GC-MS analysis. The experiments have shown coprolites to have distinctive spectra, containing strong peaks from calcite, phosphate and quartz; the presence of phosphorus may be confirmed by SEM-EDX analysis. Pottery containing organic residues of plant and animal origin has also been shown to generally display strong phosphate peaks. FT-IR has distinguished between organic resin and non-organic compositions for the black residues, with differences also being seen between organic samples that have the same physical appearance. Further analysis by CC-MS has confirmed the identification of the coprolites through the presence of coprostanol and bile acids, and shows that the majority of organic pottery residues are either fatty acids or mono- or di-acylglycerols from foodstuffs, or triterpenoid resin compounds exposed to high temperatures. One suspected resin sample was shown to contain no organic residues. and it is seen that resin samples with similar physical appearances have different chemical compositions. FT-IR is proposed as a quick and cheap method of screening archaeological samples before subjecting them to the more expensive and time-consuming method of GC-MS. This will eliminate inorganic samples such as clays and ochre from CC-MS analysis, and will screen those samples which are most likely to have a high concentration of preserved organic residues. (C) 2008 Elsevier B.V. All rights reserved.