UPIOM: a new tool of MFA and its application to the flow of iron and steel associated with car production

Identification of the flow of materials and substances associated with a product system provides useful information for Life Cycle Analysis (LCA), and contributes to extending the scope of complementarity between LCA and Materials Flow Analysis/Substances Flow Analysis (MFA/SFA), the two major tools of industrial ecology. This paper proposes a new methodology based on input-output analysis for identifying the physical input-output flow of individual materials that is associated with the production of a unit of given product, the unit physical input-output by materials (UPIOM). While the Sankey diagram has been a standard tool for the visualization of MFA/SFA, with an increase in the complexity of the flows under consideration, which will be the case when economy-wide intersectoral flows of materials are involved, the Sankey diagram may become too complex for effective visualization. An alternative way to visually represent material flows is proposed which makes use of triangulation of the flow matrix based on degrees of fabrication. The proposed methodology is applied to the flow of pig iron and iron and steel scrap that are associated with the production of a passenger car in Japan. Its usefulness to identify a specific MFA pattern from the original IO table is demonstrated.     

Wind power smoothing using fuzzy logic pitch controller and energy capacitor system for improvement Micro-Grid performance in islanding mode

The need of reducing CO₂ emissions in electricity generation field for solving global warming problems has led to increase interest in Micro-Grid (MG) especially the one with renewable sources such as solar and wind generations. Wind speed fluctuations cause high fluctuations in output power of wind turbine which cause fluctuations in fr and voltages of the MG in the islanding mode and originate stability problems. In this study, a new fuzzy logic pitch controller and an energy storage ultra capacitor are proposed and developed to smooth the output power of wind turbine and enhance MG's performance in islanding mode. These two proposed controllers are compared with the conventional PI pitch controller, which is usually used to control wind generation system when the wind speed exceeds a rated value. Obtained results proved that our two proposed strategies are effective for the MG performance improvement during islanding mode. All models and controllers are developed using Matlab^® Simulink^® environment.     

Removal of Sulfur from CaF2 Containing Desulfurization Slag Exhausted from Secondary Steelmaking Process by Oxidation

The oxidation behavior of sulfur in desulfurization slag generated from the secondary steelmaking process with air has been investigated in the temperature range of 973?K to 1373?K (700?°C to 1100?°C). Although a high removal rate of sulfur is not achieved at temperatures lower than 1273?K (1000?°C) because of the formation of CaSO₄, most of the sulfur is rapidly removed from slag as SO₂ gas in the 1273?K to 1373?K (700?°C to 1100?°C) range. This finding indicates that the desulfurization slag generated from the secondary steelmaking process can be reused as a desulfurized flux through air oxidation, making it possible to reduce significantly the amount of desulfurization slag for disposal.     

p53, Bax and Bcl-2 expression, and apoptosis in gestational trophoblast of complete hydatidiform mole

This study investigates the extent of apoptosis in complete hydatidiform mole (CHM), using an in situ 3'-end DNA labelling (TUNEL) technique on formalin-fixed and paraffin-embedded sections. The sections were also immunostained with antibodies to p53, Bax and Bcl-2 proteins. In 10 normal placenta cases and 15 CHM cases, the apoptotic index was <1 and 2-4 per cent, respectively. The labelled trophoblastic cells possessed pyknotic nuclei and densely eosinophilic cytoplasm which corresponded well to the so-called apoptotic bodies by light and electron microscopy. The p53 positive reaction was restricted to the nuclei of cytotrophoblasts and intermediate trophoblasts, while the syncytiotrophoblasts showed only rare immunolocalization. Strong p53 expression was seen most often in cytotrophoblasts of CHM (>30 per cent of nuclei) which also showed a higher apoptosis index, while cytotrophoblasts in normal placentae were weakly and focally labelled (<10 per cent of nuclei). There were statistical differences between normal and CHM cases (P<0.05). Bcl-2 accumulation, on the other hand, was observed predominantly in syncytiotrophoblasts of normal placentae, and cytotrophoblasts and intermediate trophoblasts did not express Bcl-2 in all cases. Interestingly, syncytiotrophoblasts were found to be negative for Bax protein and positive in cytotrophoblast, which is consistent with the function of the protein in conveying increased apoptosis susceptibility to this cell population. The results show that the level of apoptosis correlates with the histological type of the gestational trophoblasts, and apoptosis index is higher in cytotrophoblasts in CHM. The fact that p53 quantitative expression and an increase in the Bax/Bcl-2 ratio were also observed in CHM suggested that they may contribute partly to the high level of apoptosis.     

Subsecond Measuring Technique for In-plane Thermal Diffusivity at Local Area by the Forced Rayleigh Scattering Method

In the course of a chemical reaction or structural changes in a material, the thermal diffusivity of the material changes in response to its varying conditions. Real-time information in the form of successive data on the thermal diffusivity during the process is indispensable for an adaptive control system for material production or processing. In the present study, a measurement technique for in-plane thermal diffusivity in micro-scale and at a high repetition rate has been studied. In view of the application of this method for fast processes, the effects of property changes during a single measurement time on the measured value have been quantitatively evaluated. We have developed a measurement system of the in-plane thermal diffusivity by means of the forced Rayleigh scattering method, an optical technique with a measurement time less than 1 ms and at a micro-scale local observation area. In the present system, each thermal diffusivity measurement was conducted every 10 ms; i.e., the repetition rate was up to 100 data per second. The results of preliminary measurements of a polymethylmethacrylate plate with several repetition rates verify the reliability of this technique in tracing high-speed phenomena. Paper presented at the Seventh International Workshop on Subsecond Thermophysics, October 6–8, 2004, Orléans, France.     

A Method for Calculating Thermal Radiation Properties of Multilayer Films from Optical Constants

A calculation method for the incident angle dependence of the solar absorptance _S and the temperature dependence of the total hemispherical emittance _H of multilayer films is proposed. The method is based on calculation of _S and _H from optical constants in the wavelength region from 0.25 to 100 m for thin polymer films and deposited metal. In this paper we provide values of _S in the incident angle region from 0 to 90° and _H in the temperature range from 173.15 to 373.15 K for two-layer samples of aluminum-deposited polyimide film. The results obtained for _S and _H by the present method are compared with experimental results measured by both spectroscopic and calorimetric methods. The calculated results of _S and _H agree well with the experimental results.     

Kinetics of the reaction of H2O gas with liquid iron

The rate of the decarburization of carbon-saturated liquid iron by H20 gas between 1673 and 1873 K has been studied under conditions in which the effect of mass transfer is negligible, or a reasonable correction for its effect can be made. The rate was measured for water vapor pressures in the range 0.002 to 0.3 atm and sulfur contents in the metal from 0.005 to 0.5 mass of H20 on the surface. Sulfur was found to significantly decrease the rate, and the residual rate phenomenon was observed at high sulfur content. The rate constant for the dissociation of H20 on liquid iron is given by

Preparation of carbon fibers from syndiotactic 1,2-polybutadiene

Carbon fibers having good mechanical properties were produced from syndiotactic 1,2-polybutadiene (s-PB). Melt-spun s-PB fibers were made infusible by oxidation, irradiation, or treatments with Lewis acids, protonic acids, or peroxides. The infusibilized fibers were dehydrogenated with oxygen, chloranil, or sulfur and then carbonized. The preparative method by the AlBr₃–sulfur–heat treatment process gave carbon fibers with good mechanical strength in a high yield. A filaments bundle was immersed in a benzene solution of AlBr₃ (2g/100mL) at 42°C for 78 min under tension, washed with methanol, and then immersed in molten sulfur at 275°C for 14 min. After the adhering sulfur was purged with nitrogen at 290°C for 7 min, the bundle was heated up to a temperature of 700–3000°C under tension in a flow of nitrogen or argon for a few minutes. Carbon fibers heated to 1400°C were obtained with the tensile strength of 16.6 t/cm² and the modulus of 1420 t/cm² in a carbon yield of 82% and strain-graphitized fibers at 3000°C with 20 t/cm² and 4010 t/cm² in 70%.