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Molten slag is a critical material generated during blast furnace (BF) ironmaking. Slag flow behavior in the lower part of BF is closely related to the selection of charge materials, coke packed bed permeability, process stability, productivity, and hot metal quality. To better understand slag flow behavior, a numerical approach was applied to characterize the slag flow through a coke funnel analog and further, in a packed bed. The funnel analog was used to represent the flow of molten slag through the inter-particle voids of a coke packed bed. A critical funnel neck size, through which no slag flowed was experimentally established and confirmed by numerical modeling. The effect of wettability on slag flow shows the existence of an optimal contact angle for smooth slag flow in a funnel. The model was then applied to provide a deeper understanding of molten slag flow behavior in a packed bed, e.g., visualization of accumulation, coalescence, and breakup of slag at a particle scale. Specifically, the results show that the flow characteristics of discrete slag droplets in the packed bed require a particular quantitative approach for estimating the slag holdup. Packing structure, including pore size and particle shape, significantly affects the occurrence of slag blockage and droplet size, even when overall bed porosity is maintained constant. Slag flow along the vertical direction of the packed bed has a pseudo-steady percolation velocity. These results highlighted that this numerical approach is very helpful to understand the slag flow behavior at a particle scale, providing insight into the general features of slag flow as droplets or rivulets.

Channel iron deposits (CID), comprising pisolitic or goethitic ores, remain a prominent iron ore resource in Western Australia. Previous research work on CID pointed out their complexity in genesis...

The interaction between mineral phases in two commercial iron ores and flux materials (CaO, MgO, SiO2, and Al2O3) was studied under 0.5 kPa O2 partial pressure while heating to different temperatures. CaO was the most effective flux for liquid phase generation during sintering. For a hematite ore with few gangue components (Ore A), the formation of an initial liquid phase commenced at ~ 1275 °C, with the liquid volume increasing dramatically as temperature increased to 1300 °C. For a goethite containing hematite ore (Ore B), the formation of an initial liquid phase through interaction between goethite and CaO was observed when heating to 1225 °C, with the majority of goethite transformed to liquid at 1250 °C. The porous morphology of sintered goethite and finely distributed quartz results in a high reactivity with CaO. The initial liquid phase penetrated into the pores within the hematite matrix, promoting assimilation and by 1300 °C, all hematite in Ore B was dissolved. The hematite/martite phase in Ore B was much easier to assimilate than that in Ore A due to the presence of goethite. MgO diffused into hematite ore grains by solid-state diffusion and formed a solid solution (Fe, Mg)O∙Fe2O3 without the formation of a liquid phase. The reaction layer formed by MgO diffusion was limited to approx. 60 μm at 1300 °C. The porous morphology in goethite facilitated MgO diffusion. However, the cavities and cracks caused by goethite dehydration significantly restricted solid phase diffusion of Mg2+. There was no observed interaction between Al2O3 and SiO2 with Ores A and B when heated to 1300 °C.

Slag flow behaviour is critically important in the lower zone of the ironmaking blast furnace, and is closely related to the selection of charged raw materials, coke bed permeability, process stability and hot metal quality. To better understand the effect of slag properties on flow behaviour in the coke bed, a numerical approach was applied to characterize the slag flow through funnel analogues. These analogues were used to represent molten slag flow through the inter-particle voids of a coke packed bed. A critical funnel neck size, through which no slag flowed was experimentally established and confirmed by numerical modelling. The influence of slag wettability on the occurrence of blockage was also determined via numerical modelling. An increase in either contact angle or surface tension can make the occurrence of blockage easier. For a constant neck size, the relationship between surface tension and contact angle is non-linear. The status of the remaining slag in the funnel corresponding to different slag wettabilities was differentiated in terms of the blockage in the upper part and hanging in the lower part of the funnel. Modelling was also undertaken of slag flow through the inter-particle void between spherical particles to evaluate empirical correlations for predicting the remaining slag in the packed bed. These results show that the numerical approach is very useful in providing some level of guidance to help understand and predict the slag flow behaviour in the blast furnace ironmaking process.

Smooth operation, permeability control and high energy efficiency are critical operational indices which relate to the overall economic measure of the blast furnace (BF) ironmaking process. The BF charging system is central to the realisation of good operational indices. However, the readiness of granular material to segregate (de-mix) due to particle geometry (size, shape, distribution and density) regardless of the material has been uniformly blended, remains a challenge. This research paper presents discrete element modelling (DEM) study to investigate, characterise and compare the effects of initial positioning of high flowability pellets material in ternary ferrous mixtures with two sinter material components of different sizes. In order to elucidate quantification of the particle-particle scale distributions of particle types relative to others as charge materials mix as well as providing useful inferences on segregation and dispersion, a quantitative approach using near-neighbour separation index (NNSI) was used to give instantaneous quantitative description of the material status in space and time during multiple handling state positions within the charging system. Based on the results obtained from the DEM simulations, the initial positioning of the high flowability pellets material in the upstream of the BF charging system has a bearing on the discharge flow characteristics in the downstream discharging operations as well as mixing and segregation behaviour of the material. The mobility of the high flowability pellets particles, compounded by their relatively small size, influence the overall material movement and interactions as they are acquiescent to percolation and sieving. The observations in this study form a significant contribution for considerations of a discharge model formulation for a mathematical model possible of tracking real-time material movements in a BF charging system.

In this study, an alternative approach named near-neighbour separation index ( NNSI ) is proposed which defines mixing and segregation in terms of the nearest-neighbour particle scale methodology to characterise the evolution of particle-particle relationships in granular material flow systems so as to inform the extent of mixing and segregation (homogeneity) in space and time. Use is made of the geometrical particle information (position) as a function of time from the DEM simulations data to provide an instantaneous description and evaluation of the mixing and segregation process without due regard of particle history and initial configuration. The NNSI was found to give useful inferences on segregation and dispersion as it provides an unprecedented quantification of the particle-particle scale distributions of particles and fully provides a quantitative description of the particle mixture homogeneity. Furthermore, the NNSI is quite promising with added advantage and capability of handling discrete multi-size particle systems.

Pancreatic metastases (PM) are rare, comprising 3% of pancreatic tumours removed in sizable series of operations. This report presents the first case of metachronous pancreatic metastases from rhabdomyosarcoma successfully treated by pancreaticoduodenectomy.A 19-year old man was admitted with a tumor in the head of the pancreas, 1 year after undergoing removal of an alveolar RMS from the right hand. . Computed tomography (CT) scan demonstrates a solitary hypodence tumour of the pancreas. The patient underwent a pancreaticoduodenectomy and the postoperative course was uneventful. Pathologic examination confirmed the metastatic alveolar RMS without lymph node involvement. At most recent follow-up, 36 months after pancreaticoduodenectomy, the patient has no evidence of disease.Although rare, rhabdomyosarcoma can metastasize to the pancreas. The surgeons must be aware of this complication, and that such pancreatic metastases are potentially resectable with a good long term outcome.

Basic oxygen steelmaking (BOS) filter cake has been found to undergo a self-sintering process, improving its mechanical properties to allow easier recycling and utilization on plant. The aim of this study was to gain an understanding of the self-sintering of the BOS filter cake in terms of what reactions occurred, and how strength developed in the filter cake during self-sintering. The approach used was to characterize samples before reaction, and to measure the reactivity of the BOS filter cake during heating in air. Reacted samples were characterized and compared to self-sintered samples from the plant. The BOS filter cake consisted of very fine particles (200–500 nm) of metallic iron and wustite. Upon heating in air from 100 to 1000 °C, the BOS filter cake underwent a sequence of drying, oxidation, and calcination events. The primary reactions in self-sintering were found to be the oxidation of metallic iron and wustite to hematite and zinc ferrite, beginning at approximately 120 °C and were largely completed by 500–600 °C. These exothermic oxidation reactions at low temperatures were likely driven by the very fine particle size, and provided the energy required to heat the stockpiles and drive self-sintering. The strength required for recycling the BOS filter cake appeared to result from a network of particle–particle bonds that formed between the very fine iron oxide particles in the matrix during oxidation at elevated temperatures. Temperatures between 600 and 800 °C under oxidizing conditions are likely sufficient to form adequately strong material for transport and recycling in the BOS.

To explore the feasibility of small-scale sintering pot testing, a ‘millipot’ facility (diameter of 53 mm and height of 400 mm) was established and used to examine the sintering performance of iron ores and other non-traditional ferrous materials. The sintering performance of a millipot was examined across a range of different operational conditions (coke rate and suction pressure) and compared with an industrial sinter strand operation. Tablet tests were also performed to assist in the design of the millipot experiments and identify conditions for achieving mineral composition similar to the industrial sinter. For the millipot experiments, the materials used need to be compacted to increase the bulk density, and a higher coke rate is required to compensate the high heat loss caused by wall effects. A higher suction pressure is also necessary to maintain an oxidizing atmosphere in the sinter bed. As expected, it was not possible to eliminate the wall effect, which resulted in more primary hematite at edges of the sintered column. However, the sintered material from the center of column simulates industrial sinter reasonably well. As such, millipot provides a practical way to evaluate the sintering process and material performance at laboratory scale, helping to bridge the gap between tablet sintering and large scale pot sintering, or full scale plant trial. The results of millipot testing can be used for designing larger scale experiments or commercial sintering trials.

Introduction Les dernieres recommandations de l’HAS (2017) pour la prise en charge des peritonites d’origine diverticulaire recommande la realisation d’une resection-anastomose protegee chez les patients hemodynamiquement stables. Cependant l’utilite de la stomie de protection n’a jamais ete demontre. Methode Il s’agit d’une etude retrospective, monocentrique, incluant l’ensemble des patients operes pour peritonite d’origine diverticulaire (Hinchey 3 et 4) entre 2005 et 2020 et traites par resection-anastomose non protegee. Resultats Un total de 248 patients ont ete pris en charge pour peritonite d’origine diverticulaire. Un total de 152 patients (61,3 %) ont beneficie d’une intervention de Hartmann (IH), 96 (38,7 %) d’une resection-anastomose (RA) dont 67 non protegees (27 %). L’âge moyen des patients operes par RA etait de 61 ans. La morbidite globale etait significativement plus faible chez les patients non proteges en comparaison aux patients proteges (45 % vs 62 % ; p = 0,0047). Le taux de complications chirurgicales severes (Dindo III a V) etait de 12 % (8/67) dans le groupe RA non protegee vs 34,5 % (5/29) dans le groupe RA protegee (p = 0,5). Apres un delai de suivi de 36 mois. Le taux de stomie definitive etait de 4,5 % (3/67) dans le groupe RA non protegee vs 10 % (3/29) dans le groupe RA protegee (p = 0,4). Conclusion Dans cette etude la morbidite globale etait plus faible chez les patients non proteges apres resection-anastomose. A notre connaissance, il s’agit de la plus grande serie de resection-anastomoses non protegees pour peritonite d’origine diverticulaire. Cette strategie pourrait etre proposee en urgence chez les patients stables. Des essais randomises seront necessaires pour valider cette hypothese.

Many different approaches have been used in the past to characterise iron ore sinter mineralogy to predict sinter quality and elucidate the impacts of iron ore characteristics and process variables on the mechanisms of sintering. This paper compares the mineralogy of three sinter samples with binary basicities (mass ratio of CaO/SiO2) between 1.7 and 2.0. The measurement techniques used were optical image analysis and point counting (PC), quantitative X-ray diffraction (QXRD) and two different scanning electron microscopy systems, namely, Quantitative Evaluation of Materials by Scanning Electron Microscopy (QEMSCAN) and TESCAN Integrated Mineral Analyser (TIMA). Each technique has its advantages and disadvantages depending on the objectives of the measurement, with the quantification of crystalline phases, textural relationships between minerals and chemical compositions of the phases covered by the combined results. Some key differences were found between QXRD and the microscopy techniques. QXRD results imply that not all of the silico-ferrite of calcium and aluminium (SFCA types) are being identified on the basis of morphology in the microscopy results. The amorphous concentration determined by QXRD was higher than the glass content identified in the microscopy results, whereas the magnetite and total SFCA concentration was lower. The scanning electron microscopy techniques were able to provide chemical analysis of the phases, however, exact correspondence with textural types was not always possible and future work is required in this area, particularly for differentiation of SFCA and SFCA-I phases. The results from the various techniques are compared and the relationships between the measurement results are discussed.

This paper proposes the use of deep learning classification for acoustic monitoring of an industrial process. Specifically, the application is to process sound recordings to detect when additional air leaks through gaps between grate bars lining the bottom of the sinter strand pallets, caused by thermal cycling, aging and deterioration. Detecting holes is not possible visually as the hole is usually small and covered with a granular bed of sinter/blend material. Acoustic signals from normal operation and periods of air leakage are fed into the basic supervised classification methods (SVM and J48) and the deep learning networks, to learn and distinguish the differences. Results suggest that the applied deep learning approach can effectively detect the acoustic emissions from holes time segments with a minimum 79% of accuracy.

This chapter analyses the relation between heritage and sports events and more specifically how heritage sporting events (HSE) might be an interesting option for the sustainable development of territories engaged in sports events hosting strategies. The chapter begins with an exploration of the relation between heritage and sport. A multidisciplinary literature review is conducted to identify HSE's characteristics, which leads to a definition of this emerging concept. Implications for both academics and public authorities are discussed at the end of this chapter.

Poly(methyl methacrylate), polystyrene, and polyglycidol brushes (PMMA, PS and PGL, respectively) were grown on glassy carbon (GC) plates that were modified by the electrochemical reduction of the diazonium salt BF 4 - , + N 2 -C 6 H 4 -CH(CH 3 )-Br. The grafted -C 6 H 4 -CH(CH 3 )-Br species were effective in surface-initiating atom transfer radical polymerization (SI-ATRP) of the vinyl monomers. The structure of the polymer brushes was characterized by XPS. Static contact angles of water drops on PS, PGL and PMMA brushes were 89.5 ± 2.0, 75.1 ± 7.0 and 83.5 ± 1.4°, respectively. The polymer brushes were further evaluated as adsorbents of human serum albumin (HSA). Protein adsorption decreased in the order PS > PGL ∼ PMMA. This highlights the resistance of PGL to protein adsorption.

The negative-ion mass spectra of arylazo sulfides ArNNSR (1) show that their radical anions (1•-), in competition with the fragmentation to aryl radicals, nitrogen, and thiolate anions, generate th...

This communication reports the identification of a new HLA-DRB1*03 allele identified in three members of a Caucasian French family. This new allele has been officially named HLA-DRB1*0321 by the World Health Organization Nomenclature Committee. The complete exon 2 sequence of DRB1*0321 is identical to that of DRB1*0307 except for the first and second nucleotides of codon 37 (TT replacing AA), which lead to the substitution of a tyrosine for a phenylalanine (AAC→TTC at position 37). The family study showed that this new allele was transmitted into the HLA-A*0101/09, -B*0801/14, -Cw*0701, -DRB1*0321, -DRB3*0101, -DQB1*0503 and -DPB1*0401 haplotype. The complete exon 2 sequence of this new allele has been previously deposited in the EMBL Sequence Database under accession number AF297266.

We employ Eigenfaces to discriminate between handwritten and machine-printed text at the connected component (CC) level. Normalized images of machine print CCs are treated as points in a high-dimensional space. PCA yields a reduced-dimensional character space. Representative machine print CCs are projected into character space and a local distance threshold for each representative is automatically determined. CCs are classified as machine print if they are within the local distance threshold of their closest machine print representative. Otherwise, they are classified as handwriting. Recursive character segmentation using min graph cut is used to address the problem of touching characters. Validation over a large NIST handwriting and machine print database demonstrates precision of 93.98% and 89.1% for machine print and handwriting respectively.

Since their discovery, carbon nanotubes have been proposed for a number of applications, such as gas storage, reinforcement of composites, electrochemical energy storage, catalyst support, where the nanotexture and surface functionality are of fundamental importance. With regard to surface properties, this new form of carbon is not significantly different from the other classical carbon forms (carbon fibers, pyrolytic carbon, graphite, activated carbons,...) which are also constituted of graphitic carbon layers. Therefore, this chapter aims in its first part at presenting the porous properties and surface functionality of carbon materials and the techniques to control or modify these parameters. However, due to their nanoscale size morphology and inner cavity which can host various species, carbon nanotubes are expected to present specific properties. Mats of highly entangled nanotubes offer an open network of mesopores which favors the access of molecules and ions to the active surface. The second part of this chapter will be focused on the presentation of some specific chemical and electrochemical properties of carbon nanotubes. Filling of nanotubes and in-situ chemistry in the cavity will be documented. Application of carbon nanotubes as lithium battery or supercapacitor electrode materials will be critically discussed by comparison with other kinds of nanostructured carbons.

A series of sigma-adducts (1H-...7H-) derived from the addition of 2-nitropropenide ion to various nitrobenzofuroxans and nitrobenzofurazans have been oxidized electrochemically. The results show that the rearomatization of the carbocyclic ring of these adducts as well as that of a few additional 4,6-dinitrobenzofuroxan adducts (8 H- a-c) is associated with much higher oxidation potentials than found for the same process in the dinitro- and trinitrobenzene series. Especially high Eo values are measured for the oxidation of the 2-nitropropenide 4,6-dinitro- and 4-nitro-6-trifluoromethylsulfonylbenzofuroxan adducts 1H- and 4H- in acetonitrile: E (1H-)= 1.15 V versus SCE; Eo(4H-)=1.33V versus SCE. These values fit well with the available evidence that the chemical oxidation of these adducts requires the use of very strong oxidizing agents to proceed efficiently. The mechanism for the oxidation process has been established. It is shown to involve transfer of two electrons and liberation of one proton per sigma-complex precursor with no evidence whatsoever for the intermediacy of radical anionic species.