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ABSTRACTThe ‘Petrurgic process’ has become a prominent process to address the energy saving issue in the glass ceramic-making process. If the basic oxygen furnace (BOF) slag could be utilised by this process, the environmental problem caused by dumping the waste without recycling might also be resolved effectively. However, it is difficult to directly use BOF slag itself as a valuable material because of high melting point and large amount of iron oxide. Therefore, the current research was focused on elucidating crystallisation behaviour of the iron oxide-devoid BOF slag melt during cooling process with the intention of using the BOF slag to the Petrurgic process. The slag melt showed two crystallisation processes during cooling: the eutectic reaction at the early stage and the diffusion process at the later stage. In addition, the crystallisation mechanism was similar throughout the cooling rate, although the cooling rate influenced the morphology of the crystallisation product.

The ‘Petrurgic process’ has become a prominent process to address the energy saving issue in the glass ceramic-making process. If the basic oxygen furnace (BOF) slag could be utilised by this process, the environmental problem caused by dumping the waste without recycling might also be resolved effectively. However, it is difficult to directly use BOF slag itself as a valuable material because of high melting point and large amount of iron oxide. Therefore, the current research was focused on elucidating crystallisation behaviour of the iron oxide-devoid BOF slag melt during cooling process with the intention of using the BOF slag to the Petrurgic process. The slag melt showed two crystallisation processes during cooling: the eutectic reaction at the early stage and the diffusion process at the later stage. In addition, the crystallisation mechanism was similar throughout the cooling rate, although the cooling rate influenced the morphology of the crystallisation product.

The current research attempted to investigate the crystallisation mechanism of iron oxide-devoid basic oxygen furnace (BOF) slag with adding SiO2. First, the glass sample was prepared by adding 29 wt-% of SiO2to BOF slag, followed by eliminating iron oxide by reduction process. Non-isothermal DSC analysis together with confocal laser microscopy, XRD and EPMA mappings were carried out to observe the crystallisation process. The glass sample showed that the crystallisation process started from the surface where the main phases were identified to be akermanite, merwinite and wollastonite. In addition, the crystallisation process was affected by the nucleation temperature which was decided by the heating rate because of the difference in the nucleation rate between wollastonite and Mg-rich phases. The current results could be used to propose the feasibility of utilising BOF slag as glass-ceramics by chemical modification with heat treatment, which controls the crystallisation behaviour.

The current research attempted to investigate the crystallisation mechanism of iron oxide-devoid basic oxygen furnace (BOF) slag with adding SiO2. First, the glass sample was prepared by adding 29 wt-% of SiO2to BOF slag, followed by eliminating iron oxide by reduction process. Non-isothermal DSC analysis together with confocal laser microscopy, XRD and EPMA mappings were carried out to observe the crystallisation process. The glass sample showed that the crystallisation process started from the surface where the main phases were identified to be akermanite, merwinite and wollastonite. In addition, the crystallisation process was affected by the nucleation temperature which was decided by the heating rate because of the difference in the nucleation rate between wollastonite and Mg-rich phases. The current results could be used to propose the feasibility of utilising BOF slag as glass-ceramics by chemical modification with heat treatment, which controls the crystallisation behaviour.

The reduction behaviour of magnetite oxide by hydrogen below Curie temperature was investigated in the presence of external magnetic field by thermogravimetric analysis. The reduction rate of magnetite powder increased with increasing external magnetic field strength below Curie temperature of magnetite. In order to figure out the effect of external magnetic field on reduction of magnetite, two types of magnetite, powder and pellet, were studied. It was possible to enhance the reduction rate of magnetite powder, because the particles of magnetite in the presence of an external magnetic field exposed more surface to the reducing gas. The effects of reduction temperature, reducing agent, iron oxide type, particle size and specimen shape on the metallisation behaviour of magnetite were visually clarified below the Curie temperature under the influence of external magnetic field. Despite of the increase in reduction degree by applied magnetic field, the rate controlling step was not changed due to the formation of porous metallic iron layer that keeps the path for reducing agent to approach the unreduced iron oxide in the core of magnetite particle.

The reduction behaviour of magnetite oxide by hydrogen below Curie temperature was investigated in the presence of external magnetic field by thermogravimetric analysis. The reduction rate of magnetite powder increased with increasing external magnetic field strength below Curie temperature of magnetite. In order to figure out the effect of external magnetic field on reduction of magnetite, two types of magnetite, powder and pellet, were studied. It was possible to enhance the reduction rate of magnetite powder, because the particles of magnetite in the presence of an external magnetic field exposed more surface to the reducing gas. The effects of reduction temperature, reducing agent, iron oxide type, particle size and specimen shape on the metallisation behaviour of magnetite were visually clarified below the Curie temperature under the influence of external magnetic field. Despite of the increase in reduction degree by applied magnetic field, the rate controlling step was not changed due to the formation of porous metallic iron layer that keeps the path for reducing agent to approach the unreduced iron oxide in the core of magnetite particle.

The carbothermic reduction of MnO2with graphite has been investigated for the reduction mechanism in the temperature range of 1000–1300°C. Although several researchers studied the reduction step from MnO2to MnO, it was attempted to employ the in situtesting of reduction behaviour with the analysis of product gas composition simultaneously from the different points of view. The overall reduction rate increased with temperature, which was controlled by the carbon gasification. It is because the reduction rate of MnO2to MnO was much faster than the carbon gasification at the experimental temperatures. This was confirmed by the generation of negligible amount of CO compared with CO2in the analysis of product gases. Furthermore, the results could explain the difficult formation of manganese carbide from MnO2in contrast with the carbide formation from pure MnO.

The worldwide steel companies are expected to use low grade iron ores such as pisolitic iron ores, high Al2O3iron ores and ultrafine iron ores etc. in their sinter blends due to the depletion of high grade iron ores or for the economic reason. This study investigated the methods for improving sintering characteristics without deteriorating sintering productivity and sinter quality by blending mini-pellets comprising high Al2O3pisolitic iron ores and ultrafine iron ores containing low alumina. The results showed that the blending of iron ore mini-pellets produced by selective granulation is an effective way to improve sintering productivity and sinter quality without increasing the Al2O3content in sinter as well as to effectively utilise high Al2O3iron ores and ultrafine iron ores in the sintering process.

The worldwide steel companies are expected to use low grade iron ores such as pisolitic iron ores, high Al2O3iron ores and ultrafine iron ores etc. in their sinter blends due to the depletion of high grade iron ores or for the economic reason. This study investigated the methods for improving sintering characteristics without deteriorating sintering productivity and sinter quality by blending mini-pellets comprising high Al2O3pisolitic iron ores and ultrafine iron ores containing low alumina. The results showed that the blending of iron ore mini-pellets produced by selective granulation is an effective way to improve sintering productivity and sinter quality without increasing the Al2O3content in sinter as well as to effectively utilise high Al2O3iron ores and ultrafine iron ores in the sintering process.

The carbothermic reduction of MnO2with graphite has been investigated for the reduction mechanism in the temperature range of 1000–1300°C. Although several researchers studied the reduction step from MnO2to MnO, it was attempted to employ the in situtesting of reduction behaviour with the analysis of product gas composition simultaneously from the different points of view. The overall reduction rate increased with temperature, which was controlled by the carbon gasification. It is because the reduction rate of MnO2to MnO was much faster than the carbon gasification at the experimental temperatures. This was confirmed by the generation of negligible amount of CO compared with CO2in the analysis of product gases. Furthermore, the results could explain the difficult formation of manganese carbide from MnO2in contrast with the carbide formation from pure MnO.

In the current investigation, the thin film method was employed to clarify the formation mechanism of inclusions at the interface between refractory and liquid Fe. According to the electron probe micro-analysis (EPMA) mapping of the interface, a Si peak corresponding to SiO2was significant at the interface between the refractory and Fe and a small amount of Fe oxide existed. A reacted layer was formed in a way that initially FeO enriched liquid layer was widely distributed on the Fe surface and FeO and SiO2in the liquid layer were reduced by Al in liquid Fe to develop solid Al2O3enriched layer of inclusions. Some inclusions in the liquid Fe might be produced by the remaining oxygen in Ar gas which was supplied through the nozzle to prevent the adherence of inclusions onto it. Thermodynamic prediction was carried out to confirm if the oxygen partial pressure with increasing the oxygen activity on Fe surface could closely be related to the formation of reacted layer.

Experiments were carried out to investigate the effect of surface roughness of MgO substrate on the formation and size distribution of inclusion particles employing new experimental methodology. The reaction of MgO refractory with Al deoxidised liquid Fe can take place, which results in forming both MgO and spinel type of inclusions. The number density of inclusions increases with increasing surface roughness of the substrate, which could be explained by Gibbs–Thompson effect. Activated interfacial reactions between the substrate and liquid Fe are believed to be more dominant than the effect of increased surface roughness of the substrate on the number density of inclusions. It is recommended to use Al2O3based nozzle than MgO based one of similar surface roughness from a viewpoint of the generation of lower number density of inclusions.

The carbothermic reduction in magnetite was investigated from a kinetic viewpoint in the temperature range of 900–1200°C employing thermogravimetric analysis and quadruple mass spectrometry. The critical temperature for the activation of carbon gasification was found to be 1055°C by non-isothermal reduction experiments. The carbon gasification reaction was activated after all the Fe3O4was reduced to wüstite, i.e. at 25% reduction, and that the Fe catalysed nature of wüstite reduction to Fe was not identified before 25% reduction. The activation energy for the reduction in Fe3O4to wüstite was evaluated to be 85·5 kJ mol-1, and the reduction stage is believed to be limited by mixed control of Fe3O4reduction and carbon gasification. From 40·7 kJ mol-1of the activation energy for the reduction in wüstite to Fe, the second half reduction stage might be limited by mixed control of wüstite reduction by CO and the gaseous diffusion. It is believed that the wüstite reduced from Fe3O4has lower reactivity for the reduction to Fe compared with that originated from Fe2O3. In the present study, it was considered that the changeover in reaction mechanism might be carried out from mixed control of the reduction in Fe3O4to wüstite and carbon gasification to the reduction in wüstite to Fe with increasing reduction.

The authors present fast algorithms to reduce the computations of block matching algorithms, for motion estimation in video coding. Efficient multilevel successive elimination algorithms are based on the multilevel successive elimination. Efficient multilevel successive elimination algorithms consist of four algorithms. The first algorithm is given by the sum of absolute difference between the sum norms of sub-blocks in a multilevel successive elimination algorithm (MSEA) using the partial distortion elimination technique. By using the first algorithm, computations of MSEA can be reduced further. In the second algorithm, the sum of absolute difference (SAD) is calculated adaptively from large value to small value according to the absolute difference values between pixels of blocks. By using the second algorithm, the partial distortion elimination in the SAD calculation can occur early, therefore the computations of MSEA can be reduced. The second algorithm is useful not only with MSEA, but also with all kinds of block matching algorithms. In the third algorithm, the elimination level of the MSEA can be estimated. Accordingly, the computations of the MSEA related to the level lower than the estimated level can be reduced. The fourth algorithm is, first of all, to search the motion vector over the half sampled search points. At the second search, the authors search the unsampled search points around the tested search points where the motion vector may exist from the first search results. The motion estimation accuracy of the fourth algorithm is nearly 100% and the computations can be greatly reduced.

Massive posterior epistaxis is one of the peculiar symptoms of pseudoaneurysms of the carotid siphon. We experienced a case of trauma-related pseudoaneurysm of the carotid siphon. The lesion was initially silent except for the mass effect. We initially treated the lesion with platinum detachable coil embolization of the pseudoaneurysm sac with preservation of the parent artery. However, the patient had delayed massive epistaxis with recurrence of the pseudoaneurysm. The patient was subsequently managed with endovascular occlusion of the affected internal carotid artery using detachable balloons. Complete internal carotid artery trapping is recommended as an initial treatment modality if the patient can tolerate to the occlusion test. Careful observation and follow-up of the patient is required if the lesion is inevitably managed with coil embolization of the pseudoaneurysm sac alone.

Evidence was obtained about the mechanism responsible for platelet integrin alpha(2)beta activation by determining effects of various inhibitors on soluble collagen binding, a parameter to assess integrin alpha(2)beta(1) activation, in stimulated platelets. Agonists that can also activate platelet glycoprotein IIb/IIIa are able to activate integrin alpha(2)beta(1), but those operating via glycoprotein Ib cannot. Activation of alpha(2)beta(1) induced by low thrombin or collagen-related peptide concentrations was almost completely inhibited by apyrase, and the inhibitors wortmannin, 4-amino-5-(chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine, bisindolylmaleimide I, and SQ29548 significantly inhibited it. Activation induced by high thrombin or collagen-related peptide concentrations was far less sensitive to these inhibitors. However, only wortmannin markedly inhibited ADP-induced integrin alpha(2)beta(1) activation, and this was not ADP concentration-dependent. These results suggest that at the low agonist concentrations, the released ADP would be a primary inducer of integrin alpha(2)beta(1) activation, while at the high agonist concentrations, there would be several pathways through which integrin alpha(2)beta(1) activation can be induced. Kinetic analyses revealed that ADP-induced platelets had about the same number of binding sites (B(max)) as thrombin-induced platelets, but their affinity (K(d)) for soluble collagen was 3.7-12.7-fold lower, suggesting that activated integrin alpha(2)beta(1) induced by ADP is different from that induced by thrombin. The data are consistent with an activation mechanism involving released ADP and in which there exists two different states of activated integrin alpha(2)beta(1); these activated forms of integrin alpha(2)beta(1) would have different conformations that determine their ligand affinity.

A thin copper layer (35 nm) deposited on SiO2 has been subjected to ion-beam mixing with 80 keV Ar+ at room temperature, 550 and 650 K. Interfacial properties of irradiated samples were investigated using Rutherford backscattering spectroscopy, grazing-angle X-ray diffraction, X-ray photo-electron spectroscopy and scratch testing. The adhesion of the copper film was improved by a factor of three at a dose of 1.5 × 1016 Ar+ cm-2 by the ion-beam mixing at room temperature, while the high-temperature ion-beam mixing enhanced the adhesion by a factor of five. Ballistic mixing plays a role in the improvement of adhesion for the room-temperature ion mixing, and the creation of Cu2O phase induced by ion-beam mixing contributes to the enhancement of adhesion at high temperature.

Platelet interaction with soluble and insoluble collagens was characterized through binding studies. In contrast to resting platelets, cells reacted with activators, TS2/16 (integrin alpha2 beta1-activating antibody), thrombin, collagen-related peptide, or ADP, exhibited specific soluble collagen binding that is Mg2+-dependent, but inhibited by prostaglandin I2, Ca2+, and Gi9 (anti-integrin alpha2 beta1 antibody). Each platelet has 1500-3500 soluble collagen binding sites, with a dissociation constant of 3. 5-9 x 10(-8) M. This is the first study to show the specific binding of soluble collagen to platelets; our data strongly suggest that the receptor is integrin alpha2 beta1 after it becomes activated upon platelet activation. These results suggest that activation of platelets transforms integrin alpha2 beta1 to a state with higher affinity binding sites for soluble collagen. The soluble collagen-platelet interaction was compared with the platelet interaction with fibrillar collagen, which has until now not been demonstrated to bind specifically to platelets. Here, we demonstrated specific, biphasic fibrillar collagen binding. One phase is rapid and metal ion-independent, and accounts for most of the binding. The other phase is slow and Mg2+-dependent. The characteristic differences in the specific bindings of soluble and fibrous collagens demonstrate the different contributions of two different collagen receptors.

Pulmonary lymphangitic sarcomatosis (PLS) is not much recognized clinically although it shows similar pathological patterns and diagnostic features to pulmonary lymphangitic carcinomatosis (PLC). We report a case with hand angiosarcoma whose chest X-ray findings revealed a diffuse interstitial pattern consistent with lymphangitic spreading. The final diagnosis was made by open lung biopsy. The clinical, diagnostic and pathological features of this disease process are reviewed.

WE report the MRI findings in two patients with presumed cervical spinal cord infarcts in the anterior spinal artery territory. MRI revealed abnormal signal intensities and/or band-like enhancement in the anterior two-thirds of the cervical spinal cord, corresponding to the vascular territory of the anterior spinal artery. Clinically there was an anterior spinal cord syndrome.